WO2024114563A1

WO2024114563A1 - Communication method and apparatus

Info

Publication number: WO2024114563A1
Application number: PCT/CN2023/134276
Authority: WO
Inventors: 孙欢; 金哲; 罗之虎
Original assignee: 华为技术有限公司
Priority date: 2022-12-01
Filing date: 2023-11-27
Publication date: 2024-06-06
Also published as: CN118157714A

Abstract

The present application relates to the technical field of communications, and provides a communication method and apparatus. The method comprises: a network device receives a first signal from a second terminal device, wherein the first signal is a signal obtained by modulating a second signal into a third signal, the second signal is used for carrying first information, a first bit in the first information corresponds to Z sub-signals in the second signal, the Z sub-signals are respectively located in different time units, difference information between the Z sub-signals is used for indicating the value of the first bit, and Z is an integer greater than 1; and the network device demodulates the first signal to obtain the first information. Because the value of one bit in the first information is indicated by means of the difference information between the Z sub-signals in the second signal, when the network device demodulates the first signal modulated according to the second signal, the third signal among the received signals can be eliminated by means of differential demodulation, thereby improving the robustness of the first signal sent by the second terminal device, and enhancing the coverage performance of the first signal.

Description

A communication method and device

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of the Chinese patent application filed with the China Patent Office on December 1, 2022, with application number 202211533302.6 and application name “A Communication Method and Device”, the entire contents of which are incorporated by reference in this application.

Technical Field

The present application relates to the field of communication technology, and in particular to a communication method and device.

Background technique

Backscatter communication is a very low-power, low-cost passive radio frequency identification (RFID) communication technology, which is suitable for power-sensitive Internet of Things (IoT) and other scenarios. Backscatter communication technology can include three nodes: a sending device, a tag device, and a receiving device. When backscatter communication technology is applied to a mobile communication system (such as a 5G system), the sending device can be a terminal device and the receiving device can be a base station.

Since RFID is an extremely low-power, low-cost technology, the signals exchanged between the sending device, tag device and receiving device are relatively simple. However, when backscatter communication technology is applied to mobile communication systems, if the technology in RFID is directly used to send and receive signals, the anti-interference performance of the signals sent by devices such as tag devices may not meet the requirements of mobile communication systems. Therefore, how tag devices transmit signals in mobile communication systems is an urgent problem to be solved.

Summary of the invention

The present application provides a communication method and device, which are used to provide a signal transmission method.

In a first aspect, the present application provides a communication method, the method comprising: a network device receives a first signal from a second terminal device; the first signal is a signal obtained by modulating the second signal into a third signal, the second signal is used to carry first information, and the third signal comes from the first terminal device; the first bit in the first information corresponds to Z sub-signals in the second signal, the Z sub-signals are respectively located in different time units, and the difference information between the Z sub-signals is used to indicate the value of the first bit, and Z is an integer greater than 1; the network device demodulates the first signal to obtain the first information.

In the present application, since the value of a bit in the first information is indicated by the difference information between Z sub-signals in the second signal, when the network device demodulates the first signal modulated according to the second signal, it can use differential demodulation to eliminate the interference signal in the received first signal (for example, the interference signal can be a third signal), thereby improving the robustness of the first signal sent by the second terminal device and improving the coverage performance and anti-interference performance of the first signal.

In a possible implementation, the third signal includes at least one orthogonal frequency division multiplexing OFDM symbol;

The symbol type of the OFDM symbol is the first type, the OFDM symbol of the first type includes a first part, a second part and a third part, the second part is located between the first part and the third part, the signal corresponding to the first part is the same as the signal corresponding to the third part, and the duration corresponding to the first part is the same as the duration corresponding to the third part;

Alternatively, the symbol type of the OFDM symbol is the second type, the second type of OFDM symbol includes N parts, the duration of each of the N parts is the same, the signal corresponding to each part of the N parts of the OFDM symbol is the same, N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol.

In the present application, when the symbol type of the OFDM symbol is the first type, the impact and modification on the existing protocol is small, and the system compatibility is improved. In the present application, when the symbol type of the OFDM symbol is the second type, the signal corresponding to each of the N parts included in the OFDM symbol is the same, so that when the network device demodulates the signal modulated according to the third signal, it can use differential demodulation to eliminate the interference signal in the received signal, and can improve the utilization rate of the carrier symbol and improve the coverage performance.

In a possible implementation, the method also includes: the network device sends first indication information to the first terminal device, and the first indication information is used to indicate at least one of the following: a modulation method of the second signal; a symbol type of the OFDM symbol included in the third signal; a value of N; a length of the cyclic prefix of the OFDM symbol; a frequency domain resource position occupied by the third signal; and an average transmission power of the third signal.

In a possible implementation, the method further includes: the network device sends second indication information to the second terminal device, the second indication The information is used to indicate the information carrying mode of the second signal; the information carrying mode includes a first mode, a second mode and a third mode; wherein, the information carrying mode is the first mode, and the Z sub-signals of the second signal in the Z time units are used to indicate the value of a bit, and the Z time units are continuous in time; in the present application, when the information carrying mode is the first mode, the network device can demodulate in real time when demodulating information, thereby reducing the overhead required for caching.

The information carrying mode is the second mode, and the Z sub-signals of the second signal in the Z time units are used to indicate the value of a bit, and the Z time units are discontinuous in time; in the present application, when the information carrying mode is the second mode, more flexible discontinuous time domain allocation can obtain more time domain diversity gain and improve demodulation performance.

The information carrying mode is the third mode, and X+1 sub-signals of the second signal in X+1 time units are used to indicate values of X bits, where X is an integer greater than 1.

By using the information carrying method of the first or second method, the difference information of Z sub-signals can be used to indicate the value of one bit, thereby improving the anti-interference capability of information transmission. By using the information carrying method of the third method, each X+1 sub-signal indicates the value of X bits, which can achieve more bit information carrying with fewer signals, thereby improving the data transmission rate.

In a possible implementation, the Z time units are discontinuous in time, including: two adjacent time units in the Z time units are separated by M1 time units, where M1 is an integer greater than or equal to 1.

In a possible implementation, the first information includes a second bit, and the first bit and the second bit are any two bits included in the first information; the Z sub-signals corresponding to the first bit in the second signal are different from the Z sub-signals corresponding to the second bit in the second signal.

In the present application, the Z sub-signals corresponding to the first bit in the second signal are different from the Z sub-signals corresponding to the second bit in the second signal, thereby reducing the probability of erroneous transmission between sub-signals corresponding to different bits and improving demodulation performance.

In a possible implementation, the Z sub-signals corresponding to the first bit in the second signal are respectively located in Z time units, and two adjacent time units in the Z time units are spaced apart by M2 time units, where M2 is an integer greater than or equal to 0.

In a possible implementation manner, the third signal includes at least one OFDM symbol, and the Z time units corresponding to the first bit in the second signal are within the same OFDM symbol in the third signal.

In a possible implementation, X bits in the first information correspond to X+1 sub-signals in the second signal, and the X+1 sub-signals are respectively located in X+1 time units, where X is an integer greater than 1;

The X+1 sub-signals include 1 common sub-signal and X unique sub-signals, the common sub-signal corresponds to X bits, and the X unique sub-signals correspond to X bits one-to-one.

In a possible implementation manner, the third signal includes at least one OFDM symbol, the X+1 time units are continuous in the time domain, and the X+1 time units are within the same OFDM symbol in the third signal.

In a possible implementation manner, the difference information between the Z sub-signals is an amplitude difference, an energy difference, or a phase difference between the Z sub-signals.

In a possible implementation, if Z=2, the difference information between the Z sub-signals is an amplitude difference, an energy difference, or a phase difference between a first sub-signal and a second sub-signal of the two sub-signals;

If Z=4, the difference information between the Z sub-signals is the amplitude difference, energy difference, or phase difference between the first two sub-signals and the last two sub-signals among the four sub-signals.

In a possible implementation manner, the second terminal device is a passive device or a semi-active device, for example, the second terminal device is a tag device.

In a possible implementation manner, the second signal is a baseband signal, the third signal is an excitation signal, and the first signal is a reflection signal.

In a second aspect, the present application provides a communication method, which includes: a second terminal device receives a third signal from a first terminal device; the second terminal device modulates the second signal into a third signal to obtain a first signal; the second signal is determined based on the first information, the first bit in the first information corresponds to Z sub-signals in the second signal, the Z sub-signals are respectively located in different time units, and the difference information between the Z sub-signals is used to indicate the value of the bit, and Z is an integer greater than 1; the second terminal device sends the first signal to the network device.

The symbol type of the OFDM symbol is a first type, the OFDM symbol of the first type includes a first part, a second part and a third part, the second part is located between the first part and the third part, the signal corresponding to the first part is the same as the signal corresponding to the third part, and the duration corresponding to the first part is the same as the duration corresponding to the third part; or, the symbol type of the OFDM symbol is a second type, the OFDM symbol of the second type includes N parts, the duration of each of the N parts is the same, the signal corresponding to each part of the N parts of the OFDM symbol is the same, and N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol.

In a possible implementation, the method further includes: the second terminal device receives second indication information from the network device, the second indication information is used to indicate the information carrying mode of the second signal; the information carrying mode includes a first mode, a second mode and a third mode; wherein the information carrying mode is the first mode, the Z sub-signals of the second signal in the Z time units are used to indicate the value of a bit, and the Z time units are continuous in time; the information carrying mode is the second mode, the Z sub-signals of the second signal in the Z time units are used to indicate the value of a bit, and the Z time units are discontinuous in time;

In a possible implementation, the method further includes: the second terminal device reports capability information to the network device, wherein the capability information indicates that the modulation mode supported by the second terminal device is at least one of phase shift keying (PSK) and on-off keying (OOK) modulation.

In a possible implementation, the method also includes: the second terminal device receives third indication information, and the third indication information is used to indicate at least one of the following: a modulation method of the second signal; a symbol type of an orthogonal frequency division multiplexing OFDM symbol included in the third signal; a value of N, wherein when the symbol type of the OFDM symbol is the second type, the OFDM symbol includes N parts; the length of the cyclic prefix of the OFDM symbol; the frequency domain resource position occupied by the third signal; and the average transmission power of the third signal.

In a third aspect, the present application provides a communication method, which includes: a first terminal device receives first indication information from a network device, the first indication information is used to indicate at least one of the following information: a modulation mode of a second signal; a modulation type of an orthogonal frequency division multiplexing (OFDM) symbol included in a third signal; a value of N, wherein when the symbol type of the OFDM symbol is the second type, the OFDM symbol includes N parts; the length of the cyclic prefix of the OFDM symbol; the frequency domain resource position occupied by the third signal; the average transmission power of the third signal; the first terminal device sends the third signal to the second terminal device according to the first indication information.

In a possible implementation manner, the third signal is an excitation signal.

In a possible implementation manner, the second signal is a baseband signal, and the first signal is a reflected signal.

The symbol type of the OFDM symbol is the first type, and the first type of OFDM symbol includes a first part, a second part, and a third part. The second part is located between the first part and the third part, the signal corresponding to the first part is the same as the signal corresponding to the third part, and the duration corresponding to the first part is the same as the duration corresponding to the third part; or, the symbol type of the OFDM symbol is the second type, the OFDM symbol of the second type includes N parts, the duration of each of the N parts is the same, the signal corresponding to each of the N parts of the OFDM symbol is the same, and N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol.

In a fourth aspect, the present application provides a communication device, which can execute any one of the methods in the first to third aspects above.

In one possible design, the apparatus includes one or more processors and an interface circuit. The one or more processors are configured to support the apparatus to perform the corresponding functions of the network device or the first terminal device or the second terminal device in the method. For example, the first signal is demodulated to obtain the first information. The interface circuit is used to support the apparatus to communicate with other devices to implement receiving and/or sending functions. For example, the first signal from the second terminal device is received.

Optionally, the device may further include one or more memories, which are coupled to the processor and store necessary program instructions and/or data for the network device or the first terminal device or the second terminal device. The one or more memories may be integrated with the processor or may be separately provided from the processor. This application is not limited thereto.

The device may be a network device or a first terminal device or a second terminal device, and the interface circuit may be a transceiver or a transceiver circuit. Optionally, the transceiver may also be an input/output circuit or an interface.

The device may also be a module or device, such as a chip, in the network device or the first terminal device or the second terminal device. The interface circuit may be an input/output circuit or an interface of the module or device.

In one possible design, the apparatus includes one or more processors and an interface circuit. The one or more processors are configured to support the apparatus to perform the corresponding functions of the network device in the first aspect or any possible implementation of the first aspect. The interface circuit is used to support the apparatus to communicate with other devices to implement receiving and/or sending functions.

In one possible design, the apparatus includes one or more processors and an interface circuit. The one or more processors are configured to support the apparatus to perform the corresponding functions of the second terminal device in the second aspect or any possible implementation of the second aspect. The interface circuit is used to support the apparatus to communicate with other devices to implement receiving and/or sending functions.

In one possible design, the apparatus includes one or more processors and an interface circuit. The one or more processors are configured to support the apparatus to perform the functions corresponding to the first terminal device in the third aspect or any possible implementation of the third aspect. The interface circuit is used to support the apparatus to communicate with other devices to implement receiving and/or sending functions.

In a fifth aspect, a system is provided, comprising the network device for executing the method in the first aspect or any possible implementation of the first aspect, a second terminal device for executing the method in the second aspect or any possible implementation of the second aspect, and a first terminal device for executing the method in the third aspect or any possible implementation of the third aspect.

In a sixth aspect, a computer-readable storage medium is provided for storing a computer program, wherein the computer program comprises computer instructions for executing the method in the first aspect or any possible implementation of the first aspect.

In a seventh aspect, a computer-readable storage medium is provided for storing a computer program, wherein the computer program comprises computer instructions for executing the method in the second aspect or any possible implementation of the second aspect.

In an eighth aspect, a computer-readable storage medium is provided for storing a computer program, wherein the computer program comprises computer instructions for executing the method in the third aspect or any possible implementation of the third aspect.

In a ninth aspect, a computer program product is provided, comprising: a computer program code, which, when executed on a computer, enables the computer to execute the method in the first aspect or any possible implementation of the first aspect.

In a tenth aspect, a computer program product is provided, the computer program product comprising: a computer program code, when the computer program code is run on a computer, the computer executes the method in the above-mentioned second aspect and any possible implementation manner of the second aspect.

In an eleventh aspect, a computer program product is provided, comprising: a computer program code, which, when executed on a computer, enables the computer to execute the method in the third aspect and any possible implementation of the third aspect.

In the twelfth aspect, a chip is provided, comprising a processor, wherein the processor is coupled to a memory and is used to execute a computer program or instruction stored in the memory, so that the chip implements the method in the above-mentioned first to third aspects and any possible implementation method of the first to third aspects.

In a thirteenth aspect, a communication method is provided, the method comprising: a network in the first aspect or any possible implementation of the first aspect; The method executed by the device, and/or the method executed by the second terminal device in the second aspect or any possible implementation of the second aspect, and/or the method executed by the first terminal device in the third aspect or any possible implementation of the third aspect.

These and other aspects of the present application will become more clearly understood in the description of the following embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a network architecture of a mobile communication system applicable to an embodiment of the present application;

FIG2 is a schematic diagram of an OFDM symbol structure provided in an embodiment of the present application;

FIG3 is a schematic diagram of another OFDM symbol structure provided in an embodiment of the present application;

FIG4 is a flow chart of a communication method provided in an embodiment of the present application;

FIG5 is a schematic diagram of an OOK modulation provided in an embodiment of the present application;

FIG6 is a schematic diagram of an OOK modulation provided in an embodiment of the present application;

FIG7 is a signal schematic diagram provided in an embodiment of the present application;

FIG8 is a signal schematic diagram provided in an embodiment of the present application;

FIG9 is a signal schematic diagram provided in an embodiment of the present application;

FIG10 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application;

FIG11 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all of the embodiments. The terms "first", "second" and corresponding terminology labels in the specification, claims and drawings of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way are interchangeable where appropriate, and this is merely a way of distinguishing objects of the same attributes when describing the embodiments of the present application. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, so that a process, method, system, product or device that includes a series of units is not necessarily limited to those units, but may include other units that are not clearly listed or inherent to these processes, methods, products or devices.

The communication method provided in the embodiments of the present application can be applied to various mobile communication systems, for example, the Internet of Things (IoT), narrowband Internet of Things (NB-IoT), long term evolution (LTE), the fifth generation (5G) communication system (such as 5G new radio (NR)), a hybrid architecture of LTE and 5G, 6G or new communication systems that will appear in the future communication development, etc. The communication system can also be a machine to machine (M2M) network, a machine type communication (MTC) or other networks.

The method and device provided in the embodiments of the present application are based on the same or similar technical concepts. Since the principles of solving problems by the method and the device are similar, the implementation of the device and the method can refer to each other, and the repeated parts will not be repeated.

FIG1 is a schematic diagram of a network architecture of a mobile communication system applicable to the present application. As shown in FIG1 , the mobile communication system includes a network device 110 and at least one terminal device (such as a first terminal device 120 and a second terminal device 130 in FIG1 ). The terminal device can be fixed or movable.

In Figure 1, the first terminal device can send a signal to the second terminal device, and the signal can be called a carrier signal or an excitation signal. The second terminal device is a passive device, or a semi-active device (for example, the baseband is active but the RF is passive). For this reason, the second terminal device needs to obtain electrical energy before sending the signal. The second terminal device can convert part or all of the carrier signal from the first terminal device into electrical energy. After the second terminal device obtains electrical energy through the received carrier signal, it can drive its own circuit to modulate the baseband signal into the carrier signal to obtain the modulated signal. The modulated signal of the second terminal device can be called a RF signal or a reflected signal. In one implementation, the first terminal device is an active device that supports mobile communication systems such as 4G or 5G.

In this application, the terminal device may also be referred to as a terminal, user equipment (UE), mobile station, mobile terminal, etc. The terminal device is a device with wireless communication function (providing voice/data connectivity to users), and may also be a tag device in an RFID system. For example, the terminal device is a handheld device with wireless connection function, or a vehicle-mounted device, a vehicle-mounted module, etc. Some examples of terminal devices are: mobile phones, tablet computers, laptop computers, PDAs, mobile internet devices (MID), wearable devices, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, wireless terminals in Internet of Vehicles, wireless terminals in self-driving, remote hands, etc. The invention relates to wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, or wireless terminals in smart homes, device-to-device (D2D) terminal equipment, vehicle to everything (V2X) communication terminal equipment, smart vehicles, vehicle-machine systems (or telematics boxes, T-boxes), machine-to-machine/machine-type communications (M2M/MTC) terminal equipment, Internet of Things (IoT) terminal equipment, etc. For example, the terminal equipment may be an on-board device, a whole vehicle device, an on-board module, a vehicle, an on-board unit (OBU), a roadside unit (RSU), a T-box, a chip or a system on chip (SOC), etc. The embodiments of the present application do not limit the specific technology and specific device form adopted by the terminal equipment.

In the present application, the network device may be an access network device or a terminal device. When the network device is an access network device, the network device may be: an evolved Node B (eNB), an integrated access and backhaul (IAB) node, a radio network controller (RNC), a Node B (NB), a base station controller (BSC), a base transceiver station (BTS), a home base station (e.g., home evolved Node B, or home Node B, HNB), a baseband unit (BBU), an access point (AP) in a wireless fidelity (WIFI) system, a wireless relay node, a wireless backhaul node, a transmission point (TP) or a transmission and reception point (TRP), etc., and may also be a network device in a 5G mobile communication system. For example, the next generation NodeB (gNB) in the NR system, the transmission reception point (TRP), TP; or one or a group of antenna panels (including multiple antenna panels) of a base station in a 5G mobile communication system; or, the network device can also be a network node constituting a gNB or a transmission point. For example, a BBU, or a distributed unit (DU), etc. The embodiments of the present application do not limit the specific technology and specific device form adopted by the network device.

In some implementations, the network equipment may include a centralized unit (CU) and a distributed unit (DU). The RAN equipment including the CU node and the DU node splits the protocol layer of the gNB in the NR system, places the functions of some protocol layers in the CU for centralized control, and distributes the functions of the remaining part or all of the protocol layers in the DU, which is centrally controlled by the CU. Furthermore, the CU may be further divided into a control plane (CU-CP) and a user plane (CU-UP). The CU-CP is responsible for the control plane functions, mainly including radio resource control (RRC) and the packet data convergence protocol (PDCP) (i.e., PDCP-C) corresponding to the control plane. PDCP-C is mainly responsible for encryption and decryption of control plane data, integrity protection, data transmission, etc. The CU-UP is responsible for the user plane functions, mainly including the service data adaptation protocol (SDAP) and the PDCP (i.e., PDCP-U) corresponding to the user plane. SDAP is mainly responsible for processing the data of the core network and mapping the flow to the bearer. PDCP-U is mainly responsible for encryption and decryption, integrity protection, header compression, sequence number maintenance, data transmission, etc. of the data plane. CU-CP and CU-UP are connected through the E1 interface. CU-CP represents that gNB is connected to the core network through the NG interface and is connected to DU through the F1 interface control plane (i.e. F1-C). CU-UP is connected to DU through the F1 interface user plane (i.e. F1-U). Of course, another possible implementation is that PDCP-C is also in CU-UP.

It can be understood that in different systems, CU (including CU-CP or CU-UP) or DU may also have different names, but those skilled in the art can understand their meanings. For example, in an open radio access network (O-RAN) system, CU may also be called O-CU (open CU), DU may also be called O-DU, CU-CP may also be called O-CU-CP, and CU-UP may also be called O-CU-UP. For the convenience of description, CU, CU-CP, CU-UP and DU are described as examples in this application. The network device may also include an active antenna unit (AAU). CU implements some functions of gNB, and DU implements some functions of gNB. For example, CU is responsible for processing non-real-time protocols and services and implementing the functions of the RRC layer. DU is responsible for processing physical layer protocols and real-time services and implementing the functions of the radio link control (RLC) layer, the media access control (MAC) layer and the physical (PHY) layer. In some deployments, the CU may also be divided into a centralized unit control plane (CU-CP) node and a centralized unit user plane (CU-UP) node, wherein the CU-CP is responsible for control plane functions and the CU-UP is responsible for user plane functions.

To facilitate understanding of the embodiments of the present application, several basic concepts involved in the embodiments of the present application are briefly explained.

Orthogonal frequency division multiplexing (OFDM) symbol: In the present application, an OFDM symbol may include at least two symbol types. In one implementation, the symbol type of the OFDM symbol is a first type, and the OFDM symbol of the first type includes a first part, a second part, and a third part, the second part is located between the first part and the third part, the signal corresponding to the first part is the same as the signal corresponding to the third part, and the duration corresponding to the first part is the same as the duration corresponding to the third part.

The first part can also be called the cyclic prefix (CP) part, which is the CP of the OFDM symbol. The second and third parts can also be called the data part, which is used to carry data. The specific structure can be referred to as shown in Figure 2. As shown in Figure 2, the OFDM symbol includes CP and data. In Figure 2, CP is the first part of the OFDM symbol, and the end part of the data part (i.e., the filled part in the figure) is the same as The CP part is the same and is the third part of the OFDM symbol; the part of the data part other than the third part is the second part of the OFDM symbol. The CP part is formed by copying the last part of the data part, that is, the length of the filled part in the data part in the figure is the same as the CP length, and the content included is the same, and the CP is a copy of the signal of the filled part.

In another implementation, the symbol type of the OFDM symbol is the second type, the second type of OFDM symbol includes N parts, the duration of each of the N parts is the same, the signal corresponding to each part of the N parts of the OFDM symbol is the same, N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol.

For example, as shown in FIG3, N=4, that is, the OFDM symbol includes 4 parts, wherein the first part is the CP of the OFDM symbol, and the second to fourth parts are the data of the OFDM symbol, and the duration of each of the above four parts is the same, and the corresponding signals are the same. The OFDM symbol of this structure can ensure that the CP of the OFDM symbol and the ending segment of the data part of the OFDM symbol are the same.

Time unit: In this application, the specific length of a time unit can be determined according to the symbol type of the OFDM symbol. If the symbol type of the OFDM symbol is the first type, the length of a time unit is 1/2 of an OFDM symbol, that is, an OFDM symbol occupies 2 time units.

If the symbol type of the OFDM symbol is the second type, then the length of one time unit is 1/N of one OFDM symbol, that is, one OFDM symbol occupies N time units, and the length of each of the N parts included in the second type of OFDM symbol is the length of one time unit.

Amplitude shift keying (ASK). The modulation method that uses baseband digital signals to control the amplitude change of the carrier is called amplitude shift keying, also known as digital amplitude modulation. The simplest form is binary amplitude shift keying (2ASK).

Exemplarily, 2ASK modulation can be implemented by a switch circuit. The carrier is turned on or off under the control of a digital signal 1 or 0. When the digital signal is 1, the signal with amplitude A is turned on, and at this time, a signal with amplitude A is sent on the transmission channel; when the digital signal is 0, the signal with amplitude B is turned on, and at this time, a signal with amplitude B is sent on the transmission channel. Therefore, the receiving end can determine whether the digital signal is 1 or 0 based on the amplitude of the signal.

Phase shift keying (PSK) is a modulation technique that uses the carrier phase to represent the input signal information. For example, when the digital signal is 1, the signal with a phase of 0 is connected, and at this time, a signal with a phase of 0 is sent on the transmission channel; when the digital signal is 0, the signal with a phase of π is connected, and at this time, a signal with a phase of π is sent on the transmission channel. Therefore, the receiving end can determine whether the digital signal is 1 or 0 based on the phase of the signal.

The above is just an example. The tag can also achieve amplitude modulation and phase modulation by using an impedance matching circuit, and this application is not limited to this.

On-Off Keying (OOK) modulation. OOK modulation is a special case of 2ASK modulation.

For example, OOK modulation can be implemented by a switch circuit. The carrier is turned on or off under the control of a digital signal 1 or 0. When the digital signal is 1, the carrier is connected, and the transmission channel has a carrier to send. When the digital signal is 0, no carrier is connected, and no carrier is sent on the transmission channel. Therefore, the receiving end can determine whether the digital signal is 1 or 0 by detecting whether there is a carrier.

When OOK modulation is applied in NR or LTE systems, the amplitude (or envelope, level or energy, etc.) with high amplitude (e.g., higher than a certain threshold, or non-zero) is called OOK modulation symbol {1}, or OOK modulation symbol on (ON), or OOK modulation symbol on; the amplitude (or envelope, level or energy, etc.) with low amplitude (e.g., lower than a certain threshold, or 0) is called OOK modulation symbol {0}, or OOK modulation symbol off (OFF), or OOK modulation symbol off. The amplitude is defined relative to the amplitude demodulation threshold of the receiver. Amplitude greater than the demodulation threshold is called high amplitude, and amplitude less than the demodulation threshold is called low amplitude.

In the present application, the OOK modulation symbol is turned on (ON) and is called an ON symbol; the OOK modulation symbol is turned off (OFF) and is called an OFF symbol.

In the NR system, in addition to the introduction of reduced capability (RedCap) terminal devices suitable for massive machine type communication (mMTC) services, passive terminal devices such as tag devices are also introduced. As mentioned above, the tag device can send a reflection signal according to the excitation signal, wherein the excitation signal is generated by performing an inverse fast Fourier transformation (IFFT) on a frequency domain sequence of a certain length, such as a ZC (Zadoff-Chu) sequence, a discrete Fourier transform (DFT) sequence, or other bit sequences. Optionally, the signal bandwidth corresponding to a frequency domain sequence of a certain length can be 5MHz or 20MHz. The excitation signal can also be a signal obtained by performing a fast Fourier transform on a time domain sequence of a certain length to obtain a frequency domain sequence, and then selecting one or more RBs in the middle of the frequency domain sequence for IFFT. Among them, the time domain sequence of a certain length can be a full 1 sequence, a ZC sequence, etc. Optionally, the signal bandwidth corresponding to multiple RBs can be 5MHz or 20MHz. Alternatively, the excitation signal may also be a single-tone single-carrier signal generated at a specific frequency domain position. The excitation signal may include two functions: providing power to the tag device and serving as a carrier signal of the reflected signal emitted by the tag device. A part of the signal (for example, the first signal of the preset duration received in the excitation signal) is converted into electrical energy (or energy), and then the energy is used to drive its own circuit to work, modulate the baseband signal generated by itself into the excitation signal, and obtain the reflected signal.

If the tag device applied to the NR system also uses the modulation method in the RFID system to modulate the excitation signal, the obtained reflected signal cannot meet the standard of the NR system. For example, in the RFID system, the tag device can only use absolute amplitude modulation or absolute phase modulation to generate the reflected signal. After the receiving end receives the reflected signal, it determines the information carried by the reflected signal according to the amplitude or phase. If applied to the NR system, when the first terminal device sends the excitation signal, the second terminal device (as a tag device) and the network device can both receive the excitation signal, so the network device can simultaneously receive the excitation signal and the reflected signal generated according to the excitation signal. If the second terminal device uses absolute amplitude modulation or absolute phase modulation to generate the reflected signal, then because the excitation signal and the reflected signal have the same frequency, the amplitude or phase is also similar, on the network device side, the excitation signal will cause co-frequency interference to the reflected signal, and the network device cannot accurately demodulate the information carried in the reflected signal according to the amplitude or phase of the reflected signal. To this end, the present application provides a new signal modulation method that can be applied to tag devices in NR systems to improve the anti-interference performance of reflected signals, which will be described in detail below.

The network architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. A person of ordinary skill in the art can appreciate that with the evolution of the network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

Some scenarios in the embodiments of the present application are explained by taking the scenarios of the NR network in the wireless communication network as an example. It should be pointed out that the solutions in the embodiments of the present application can also be applied to other wireless communication networks, and the corresponding names can also be replaced by the names of corresponding functions in other wireless communication networks.

As shown in Figure 4, a flow chart of a communication method provided by an embodiment of the present application is provided. When the method flow is applied to the system shown in Figure 1, the network device in Figure 1 can execute the method executed by the network device in the following process, the first terminal device in Figure 1 can execute the method executed by the first terminal device in the following process, and the second terminal device in Figure 1 can execute the method executed by the second terminal device in the following process. It can be understood that the embodiments shown below do not specifically limit the specific structure of the execution subject of the method provided by the embodiment of the present application. As long as it is possible to communicate according to the method provided by the embodiment of the present application by running a program that records the code of the method provided by the embodiment of the present application, for example, the execution subject can be a terminal device or a functional module in the terminal device that can call and execute a program, or the execution subject can be a network device or a functional module in the network device that can call and execute a program. The following only takes the terminal device or the network device as an example for explanation.

S401: The first terminal device sends a third signal to the second terminal device; correspondingly, the second terminal device receives the third signal from the first terminal device.

The third signal may also be referred to as an excitation signal or a carrier signal. The present application does not limit how the third signal is specifically generated. For example, the third signal may be obtained by performing an inverse fast Fourier transform (IFFT) on a frequency domain sequence of a certain length, such as a ZC (Zadoff-Chu) sequence, a discrete Fourier transform (DFT) sequence, or other bit sequences. Optionally, the signal bandwidth corresponding to a frequency domain sequence of a certain length may be 5 MHz or 20 MHz. For example, the third signal may also be obtained by performing a fast Fourier transform on a time domain sequence of a certain length to obtain a frequency domain sequence, and then selecting one or more RBs in the middle of the frequency domain sequence for IFFT. Among them, a time domain sequence of a certain length may be an all-1 sequence, a ZC sequence, etc. Optionally, the signal bandwidth corresponding to multiple RBs may be 5 MHz or 20 MHz. Alternatively, the third signal may also be a single-tone single-carrier signal generated at a specific frequency domain position.

The third signal includes at least one OFDM symbol. In the present application, the OFDM symbol may include at least two symbol types. In one implementation, the symbol type of the OFDM symbol is a first type, and the OFDM symbol of the first type includes a first part, a second part, and a third part, the second part is located between the first part and the third part, and the signal corresponding to the first part is the same as the signal corresponding to the third part. The specific structure can refer to the above-mentioned Figure 2.

In another implementation, the symbol type of the OFDM symbol is the second type, the second type of OFDM symbol includes N parts, the duration of each of the N parts is the same, the signal corresponding to each part of the N parts of the OFDM symbol is the same, N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol, and the specific structure can refer to the previous Figure 3.

By designing an OFDM symbol to include N identical parts, the third signal sent by the first terminal device can be completely identical within multiple consecutive time units, which helps the network device to differentially demodulate the signal modulated according to the third signal and improve the signal's anti-interference performance.

In the present application, the network device may indicate information such as the symbol type of the OFDM symbol to the first terminal device. For example, the network device sends first indication information to the first terminal device, and the first indication information is used to indicate at least one of the following:

A symbol type of an OFDM symbol included in the third signal, where the symbol type is the first type or the second type;

The value of N, wherein if the symbol type of the OFDM symbol is the second type, then the first indication information may indicate the value of N; if the symbol type of the OFDM symbol is the first type, then the value of N does not need to be indicated;

The length of the CP of the OFDM symbol; the frequency domain resource position occupied by the third signal; and the average transmission power of the third signal, where the average transmission power may be the average transmission power of the third signal in each resource element.

If one of the above information is not indicated, the information is preset. For example, if the first indication information does not indicate the symbol type of the OFDM symbol, the symbol type of the OFDM symbol can be preset to the first type or the second type. For example, if the first indication information does not indicate the value of N, the value of N can be a preset value. For example, if the first indication information does not indicate the length of the CP, the length of the CP can be a preset length.

In the present application, the first indication information may also indicate the modulation mode of the second signal. The second signal is a signal generated by the second terminal device, and the second signal may be differential modulation or differential coding plus absolute modulation. Among them, differential modulation may include amplitude differential modulation, phase differential modulation and other modulation methods. For example, amplitude differential modulation may be differential OOK modulation, and phase differential modulation may be differential phase shift keying (DPSK) modulation, etc. The specific content will be described in detail later.

In one implementation, when the modulation mode of the second signal is phase differential modulation, it may be implicitly indicated that the value of N is equal to 2. When the modulation mode of the second signal is amplitude differential modulation, it may be implicitly indicated that the preset value of N is equal to 2.

S402: The second terminal device modulates the second signal into the third signal to obtain the first signal.

The second signal is determined according to the first information, and the second signal is used to carry the first information. The first information may be a bit sequence, including at least one bit. The specific content of the bits included in the first information is not limited in this application, and may be any information that the second terminal device needs to send.

In the present application, the second terminal device may modulate the first information into the second signal using a modulation method such as OOK modulation or PSK modulation, wherein OOK modulation includes absolute OOK modulation and differential OOK modulation; PSK modulation includes absolute PSK modulation and DPSK modulation. In one implementation, the second terminal device may report capability information to the network device, and the capability information indicates that the modulation method supported by the second terminal device is at least one of PSK modulation and OOK modulation.

In the present application, the second terminal device may receive third indication information from the network device or the first terminal device, where the third indication information is used to indicate at least one of the following:

A modulation mode of the second signal, such as PSK modulation or OOK modulation;

The symbol type of the orthogonal frequency division multiplexing OFDM symbol included in the third signal, for example, the first type or the second type;

a value of N, wherein when the symbol type of the OFDM symbol is the second type, the OFDM symbol includes N parts;

The length of the cyclic prefix of the OFDM symbol;

The frequency domain resource position occupied by the third signal;

The average transmission power of the third signal.

In one implementation, when the modulation mode of the second signal is PSK modulation, it may be implicitly indicated that the value of N is equal to 2. When the modulation mode of the second signal is OOK modulation, it may be implicitly indicated that the preset value of N is equal to 2.

If one of the above information is not indicated, the information is preset.

In the present application, in order to improve the anti-interference ability of the signal, the second terminal device can modulate the first information into the second signal using differential modulation methods such as differential OOK modulation or DPSK modulation. When using differential modulation, multiple sub-signals of the second signal in multiple time units are used to indicate the value of a bit in the first information.

Taking the first information including the first bit as an example, the first bit in the first information corresponds to Z sub-signals in the second signal, the Z sub-signals are respectively located in different time units, and the difference information between the Z sub-signals is used to indicate the value of the bit, Z is an integer greater than 1, and Z is an even number. In other words, the Z sub-signals in the second signal can be used to indicate the value of a bit in the first information, the Z sub-signals are located in the Z time units, and the Z sub-signals correspond to the Z time units one by one.

In the present application, the difference information between Z sub-signals may refer to the amplitude difference, energy difference or phase difference between the Z sub-signals, that is, the amplitude difference, energy difference or phase difference between the first Z/2 sub-signals and the last Z/2 sub-signals among the Z sub-signals.

In one implementation, if Z=2, the difference information between the Z sub-signals is the amplitude difference, energy difference, or phase difference between the first sub-signal and the second sub-signal of the two sub-signals.

In one implementation, if Z=4, the difference information between the Z sub-signals is the amplitude difference, energy difference, or phase difference between the first two sub-signals and the last two sub-signals among the four sub-signals.

For example, take Z=2 and the second signal adopts differential OOK modulation as an example. When Z=2, one of the first information Specifically corresponds to two sub-signals in the second signal, for example, the first bit corresponds to sub-signal 1 in time unit 1 and sub-signal 2 in time unit 2. When the amplitude difference or energy difference between sub-signal 1 and sub-signal 2 is 0, the value of the first bit is 0; when the absolute value of the amplitude difference or energy difference between sub-signal 1 and sub-signal 2 is 1, the value of the first bit is 1.

Specifically, taking amplitude as an example, when the value of the first bit is 0, the amplitude of sub-signal 1 in time unit 1 is the same as the amplitude of sub-signal 2 in time unit 2, that is, the amplitude difference between sub-signal 1 and sub-signal 2 is 0. For example, as shown in (a) of FIG5 , sub-signal 1 and sub-signal 2 are both OOK signals of the ON symbol, and the amplitudes are both 1; when the sub-signal 1 received by the receiving end in time unit 1 is the OOK signal of the ON symbol, and the sub-signal 2 received in time unit 2 is the OOK signal of the ON symbol, it can be determined that the values of the bits corresponding to sub-signal 1 and sub-signal 2 are 0. Alternatively, as shown in (b) of FIG5 , sub-signal 1 and sub-signal 2 are both OOK signals of the OFF symbol, and the amplitudes are both 0, that is, the amplitude difference between sub-signal 1 and sub-signal 2 is 0; when the sub-signal 1 received by the receiving end in time unit 1 is the OOK signal of the OFF symbol, and the sub-signal 2 received in time unit 2 is the OOK signal of the OFF symbol, it can be determined that the values of the bits corresponding to sub-signal 1 and sub-signal 2 are 0.

When the value of the first bit is 1, the amplitude of sub-signal 1 in time unit 1 is different from the amplitude of sub-signal 2 in time unit 2. For example, as shown in (a) in FIG6 , sub-signal 1 is an OOK signal of the ON symbol with an amplitude of 1; sub-signal 2 is an OOK signal of the OFF symbol with an amplitude of 0; at this time, the absolute value of the amplitude difference between sub-signal 1 and sub-signal 2 is 1. When sub-signal 1 received by the receiving end in time unit 1 is an OOK signal of the ON symbol, and sub-signal 2 received in time unit 2 is an OOK signal of the OFF symbol, it can be determined that the values of the bits corresponding to sub-signal 1 and sub-signal 2 are 1. Alternatively, as shown in (b) in FIG6 , sub-signal 1 is an OOK signal of the OFF symbol with an amplitude of 0; sub-signal 2 is an OOK signal of the ON symbol with an amplitude of 1; at this time, the absolute value of the amplitude difference between sub-signal 1 and sub-signal 2 is 1. When the sub-signal 1 received by the receiving end in time unit 1 is an OOK signal of the OFF symbol, and the sub-signal 2 received in time unit 2 is an OOK signal of the ON symbol, it can be determined that the values of the bits corresponding to sub-signal 1 and sub-signal 2 are 1.

For another example, take Z=2 and the second signal adopts DPSK modulation as an example. When Z=2, one bit in the first information corresponds to two sub-signals in the second signal, for example, the first bit corresponds to sub-signal 1 in time unit 1 and sub-signal 2 in time unit 2. When the phase difference between sub-signal 1 and sub-signal 2 is 0, the value of the first bit is 0; when the absolute value of the phase difference between sub-signal 1 and sub-signal 2 is π, the value of the first bit is 1.

Specifically, when the value of the first bit is 0, the phase of sub-signal 1 in time unit 1 is the same as the phase of sub-signal 2 in time unit 2. For example, sub-signal 1 and sub-signal 2 are both PSK signals with an initial phase of 0; or, sub-signal 1 and sub-signal 2 are both PSK signals with an initial phase of π. At this time, the phase difference between sub-signal 1 and sub-signal 2 is 0. When the receiving end receives sub-signal 1 with an initial phase of 0 in time unit 1 and receives sub-signal 2 with an initial phase of 0 in time unit 2, or when the receiving end receives sub-signal 1 with an initial phase of π in time unit 1 and receives sub-signal 2 with an initial phase of π in time unit 2, it can be determined that the values of the bits corresponding to sub-signal 1 and sub-signal 2 are 0.

When the value of the first bit is 1, the phase of sub-signal 1 in time unit 1 is different from the phase of sub-signal 2 in time unit 2, for example, the initial phase difference between sub-signal 1 and sub-signal 2 is π. For example, sub-signal 1 is a PSK signal with an initial phase of 0, and sub-signal 2 is a PSK signal with an initial phase of π; or, sub-signal 1 is a PSK signal with an initial phase of π, and sub-signal 2 is a PSK signal with an initial phase of 0. At this time, the absolute value of the phase difference between sub-signal 1 and sub-signal 2 is π. When the receiving end receives sub-signal 1 with an initial phase of 0 in time unit 1 and receives sub-signal 2 with an initial phase of π in time unit 2, or when the receiving end receives sub-signal 1 with an initial phase of π in time unit 1 and receives sub-signal 2 with an initial phase of 0 in time unit 2, it can be determined that the values of the bits corresponding to sub-signal 1 and sub-signal 2 are 1.

In the present application, if Z=4, the amplitude difference between the first two sub-signals and the last two sub-signals in the four sub-signals may include the amplitude difference between the first sub-signal and the third sub-signal in the four sub-signals, and the amplitude difference between the second sub-signal and the fourth sub-signal in the four sub-signals. Similarly, the energy difference or phase difference between the first two sub-signals and the last two sub-signals in the four sub-signals is also determined according to the above description, which will not be repeated here. Among them, the first sub-signal in the four sub-signals refers to the first signal in the time domain of the four sub-signals, and other cases are similar and will not be repeated.

For example, take Z=4 as an example. When Z=4, one bit in the first information corresponds to four sub-signals in the second signal, for example, the first bit corresponds to sub-signal 1 in time unit 1, sub-signal 2 in time unit 2, sub-signal 3 in time unit 3, and sub-signal 4 in time unit 4. When the amplitude difference between sub-signal 1 and sub-signal 3 is 0, and the amplitude difference between sub-signal 2 and sub-signal 4 is 0, the value of the first bit is 0; when the absolute value of the amplitude difference between sub-signal 1 and sub-signal 3 is 1, and the absolute value of the amplitude difference between sub-signal 2 and sub-signal 4 is 1, the value of the first bit is 1.

Specifically, when the value of the first bit is 0, sub-signal 1 and sub-signal 3 are both OOK signals of the OFF symbol, and sub-signal 2 and sub-signal 4 are both OOK signals of the ON symbol. At this time, the amplitude difference between sub-signal 1 and sub-signal 3 is 0, and the amplitude difference between sub-signal 2 and sub-signal 4 is 0. The amplitude difference of 4 is also 0.

When the value of the first bit is 1, sub-signal 1 and sub-signal 4 are both OOK signals of the ON symbol, and sub-signal 2 and sub-signal 3 are both OOK signals of the OFF symbol. At this time, the amplitude difference between sub-signal 1 and sub-signal 3 is 1, and the amplitude difference between sub-signal 2 and sub-signal 4 is 1.

The above is only an example, and the corresponding relationship between the value of the first bit and the amplitude of sub-signal 1 to sub-signal 4 can also be as shown in Table 1.

Table 1

In Table 1, when the amplitudes of sub-signals 1 to 4 are 0101, it means that sub-signal 1 is an OOK signal of an OFF symbol, sub-signal 2 is an OOK signal of an ON symbol, sub-signal 3 is an OOK signal of an OFF symbol, and sub-signal 4 is an OOK signal of an ON symbol. The same is true for other situations, which will not be described in detail here.

In the present application, the information carrying mode adopted by the second signal may include the first mode, the second mode and the third mode. The information carrying mode may indicate the corresponding relationship between the bits in the first information and the sub-signals in the second signal.

In one implementation, the network device sends second indication information to the second terminal device, and the second indication information is used to indicate the information carrying mode of the second signal. In another implementation, the information carrying mode of the second signal is preset, and this application does not limit this.

When the information carrying mode is the first mode, Z sub-signals of the second signal in Z time units are used to indicate the value of one bit, and the Z time units are continuous in time.

In the first manner, two different bits in the first information correspond to different Z sub-signals, that is, the Z sub-signals corresponding to one bit in the first information and the Z sub-signals corresponding to another bit do not have the same sub-signal. For example, the first information includes the second bit, and the first bit and the second bit are any two bits included in the first information; the Z sub-signals corresponding to the first bit in the second signal are different from the Z sub-signals corresponding to the second bit in the second signal.

For example, as shown in Fig. 7, the second signal includes 6 sub-signals, namely sub-signal 1 to sub-signal 6, which are located in 6 consecutive time units, namely time unit 1 to time unit 6. Taking Z=2 as an example, sub-signal 1 and sub-signal 2 can be used to indicate the value of bit 1 in the first information, sub-signal 3 and sub-signal 4 can be used to indicate the value of bit 2 in the first information, and sub-signal 5 and sub-signal 6 can be used to indicate the value of bit 3 in the first information.

In one implementation, if the information carrying mode indicated by the network device through the second indication information is the first mode, then the second indication information can also indicate whether the index of the starting time unit corresponding to each bit is an even number or an odd number. In the present application, the value of Z can be an even number, and by indicating whether the index of the starting time unit is an even number or an odd number, the second terminal device can accurately determine the time unit corresponding to each bit.

When the information carrying mode is the second mode, Z sub-signals of the second signal in Z time units are used to indicate the value of a bit, and the Z time units are not continuous in time.

In the second manner, two different bits in the first information correspond to different Z sub-signals, and the details may refer to the description in the first manner.

In the second manner, the Z time units are discontinuous in time, which may mean that two adjacent time units in the Z time units are separated by M1 time units, where M1 is an integer greater than or equal to 1.

For example, as shown in Figure 7, taking Z=2, M1=2 as an example, sub-signal 1 and sub-signal 4 can be used to indicate the value of bit 1 in the first information, sub-signal 2 and sub-signal 5 can be used to indicate the value of bit 2 in the first information, and sub-signal 3 and sub-signal 6 can be used to indicate the value of bit 3 in the first information.

In one implementation, if the information carrying mode indicated by the network device through the second indication information is the second mode, the second indication information may also indicate whether the index of the starting time unit corresponding to each bit is an even number or an odd number, and the value of M1. In this way, the second terminal device can accurately determine the time unit corresponding to each bit.

By using the first or second information carrying method, it is possible to indicate one bit through the difference information of Z sub-signals. value, thereby improving the anti-interference ability of information transmission.

When the information carrying mode is the third mode, X+1 sub-signals of the second signal in X+1 time units are used to indicate the values of X bits, where X is an integer greater than 1.

The X bits in the first information correspond to X+1 sub-signals in the second signal, and the X+1 sub-signals are respectively located in X+1 time units, where X is an integer greater than 1; wherein the X+1 sub-signals include 1 common sub-signal and X unique sub-signals, the common sub-signal corresponds to the X bits, and the X unique sub-signals correspond to the X bits one by one. wherein the common sub-signal is a sub-signal to which multiple bits correspond together, and the unique sub-signal is a sub-signal to which only one bit corresponds.

In the third manner, the Z sub-signals corresponding to one bit in the first information and the Z sub-signals corresponding to another bit in the first information have the same sub-signal.

For example, as shown in FIG7 , taking Z=2 as an example, sub-signal 1 is a common sub-signal, and sub-signals 2 to 5 are specific sub-signals. Sub-signals 1 and 2 can be used to indicate the value of bit 1 in the first information, sub-signal 1 and sub-signal 3 can be used to indicate the value of bit 2 in the first information, sub-signal 1 and sub-signal 4 can be used to indicate the value of bit 3 in the first information, sub-signal 1 and sub-signal 5 can be used to indicate the value of bit 4 in the first information, and sub-signal 1 and sub-signal 6 can be used to indicate the value of bit 5 in the first information.

In one implementation, if the information carrying mode indicated by the network device through the second indication information is the third mode, then the second indication information can also indicate at least one of the following: the value of X or X+1; the starting time unit of the X+1 time unit corresponding to the X+1 sub-signals; the ending time unit of the X+1 time unit corresponding to the X+1 sub-signal; the offset value of the time unit where the common sub-signal in the X+1 sub-signals is located relative to the starting position or ending position of the X+1 time unit.

By using the information carrying method of the third mode, every X+1 sub-signals indicate the value of X bits, so that more bit information can be carried by fewer signals, thereby improving the data transmission rate.

In the present application, the second terminal device may multiply the second signal by the third signal to obtain the modulated first signal. In one implementation, if the information carrying mode of the second signal is the first mode or the second mode, then the Z time units corresponding to the first bit in the first information in the second signal are within the same OFDM symbol in the third signal.

In one implementation, if the information carrier of the second signal is sent in the third manner, then when the X bits in the first information correspond to X+1 time units, these X+1 time units are continuous in the time domain, and the X+1 time units are within the same OFDM symbol in the third signal.

S403: The second terminal device sends a first signal to the network device; correspondingly, the network device receives the first signal from the second terminal device.

The first signal may also be called a reflected signal or a radio frequency signal.

S404: The network device demodulates the first signal to obtain first information.

The specific process of how the network device demodulates the first signal is not limited and will not be described in detail here.

Through the method provided in the present application, since the value of a bit in the first information is indicated by the difference information between Z sub-signals in the second signal, when the network device demodulates the first signal modulated according to the second signal, it can use differential demodulation to eliminate the received interference signal, improve the robustness of the signal, and improve the coverage performance of the signal.

Assuming that the second signal is a and the third signal is i, the first signal received by the network device can be expressed as:

r=a*i.

Furthermore, the network device may also receive an interference signal. For the present application, the interference signal may be a third signal sent by the first terminal device. Then, the first signal received by the network device may be modified into the following form:

r=a*i+i.

Taking time unit 1 and time unit 2 as examples, the sub-signal a1 of the second signal in time unit 1 and the sub-signal a2 in time unit 2 are used to indicate the value of the first bit in the first information. The signal of the third signal in time unit 1 is represented as i1, and the signal in time unit 2 is represented as i2; the signal of the first signal in time unit 1 is represented as r1, and the signal in time unit 2 is represented as r2.

In one implementation, if the symbol type of the OFDM symbol is the first type, then OFDM symbol 1 in the third signal occupies time unit 1 and time unit 2. In this implementation, assuming that the CP length of the OFDM symbol is the first duration, and the length of a time unit is greater than the first duration, then as shown in FIG8 , the network device takes a signal of the first length starting from the start position of time unit 1 in the first signal as r1, and takes a signal of the first length starting from the end position of time unit 2 in the first signal as r2.

Correspondingly, sub-signal i1 is a signal of the third signal starting from the start position of time unit 1 and having a length of the first length; sub-signal i2 is a signal of the third signal starting from the end position of time unit 2 and having a length of the first length. That is, i1 is the signal corresponding to the CP in OFDM symbol 1, that is, i1 is the signal of the first part in OFDM symbol 1; i2 is the signal of the third part in OFDM symbol 1, That is, the end position of i2 is the end position of OFDM symbol 1, and the length of i2 is the first duration. This ensures that i1=i2.

Correspondingly, the network device takes the signal of the second signal starting from the start position of time unit 1 and having a length of the first length as a1, and takes the signal of the second signal starting from the end position of time unit 2 and having a length of the first length as a2.

In another implementation, if the symbol type of the OFDM symbol is the second type, and the OFDM symbol includes N parts, then the OFDM symbol 1 in the third signal occupies N time units. Taking N=2 as an example, the OFDM1 symbol occupies time unit 1 and time unit 2. In this implementation, assuming that the CP length of the OFDM symbol is the first duration, and the length of one time unit is equal to the first duration, then as shown in FIG9 , the network device takes the signal from the start position of time unit 1 to the end position of time unit 1 in the first signal as r1, and takes the signal from the start position of time unit 2 to the end position of time unit 2 in the first signal as r2.

Correspondingly, sub-signal i1 is a signal in the third signal from the start position of time unit 1 to the end position of time unit 1; sub-signal i2 is a signal in the third signal from the start position of time unit 2 to the end position of time unit 2. Since the signal of the second type of OFDM symbol in each time unit is the same, it can be ensured that i1=i2.

Correspondingly, the network device takes the signal from the start position of time unit 1 to the end position of time unit 1 in the second signal as a1, and takes the signal from the start position of time unit 2 to the end position of time unit 2 in the second signal as a2.

In combination with the above description, the process of demodulating information by the network device is explained by taking the second terminal device using differential OOK modulation in the second signal as an example.

After the network device receives the first signal, it performs a subtraction operation on the signal r1 of the first signal in time unit 1 and the signal r2 in time unit 2, and obtains r1-r2=(a1*i1+i1)-(a2*i2+i2)=(a1*i1-a2*i2)+(i1-i2). Since i1=i2, r1-r2=(a1*i1-a2*i2). Further, when the value of the first bit is 1, a1 and a2 are not equal, for example, a1 is an OOK signal with an ON symbol and a2 is an OOK signal with an OFF symbol, r1-r2=a1*i1-a2*i2. When the value of the first bit is 0, a1 and a2 are equal, r1-r2=0, and the network device can determine whether the value of the first bit is 0 or 1 by energy judgment.

In combination with the above description, the process of the network device demodulating information is explained by taking the second terminal device using DPSK modulation in the second signal as an example.

After receiving the first signal, the network device performs a subtraction operation on the signal r1 of the first signal in time unit 1 and the signal r2 in time unit 2, and obtains r1-r2=(a1*i1+i1)-(a2*i2+i2)=(a1*i1-a2*i2)+(i1-i2). Since i1=i2, r1-r2=(a1*i1-a2*i2). When the value of the first bit is 1, a1 is not equal to a2, that is, a1 is equal to -a2, r1-r2=2a1*i1. When the value of the first bit is 0, a1 is equal to a2, r1-r2=0, and the network device can determine whether the value of the first bit is 0 or 1 by energy judgment.

For another example, taking four time units, namely time unit 1, time unit 2, time unit 3 and time unit 4 as examples, the sub-signal a1 of the second signal in time unit 1, the sub-signal a2 in time unit 2, the sub-signal a3 in time unit 3 and the sub-signal a4 in time unit 4 are used to indicate the value of the first bit in the first information. The signal of the third signal in time unit 1 is represented as i1, the signal in time unit 2 is represented as i2, the signal in time unit 3 is represented as i3, and the signal in time unit 4 is represented as i4; the signal of the first signal in time unit 1 is represented as r1, the signal in time unit 2 is represented as r2, the signal in time unit 3 is represented as r3, and the signal in time unit 4 is represented as r4. Among them, i1=i2=i3=i4.

In combination with the above description, if the second terminal device uses differential OOK modulation in the second signal, the process of demodulating information by the network device is explained as an example.

After the network device receives the first signal, it performs a subtraction operation on signal r1 of the first signal in time unit 1 and signal r2 of time unit 2 to obtain r1-r2=(a1*i1+i1)-(a2*i2+i2)=(a1*i1-a2*i2)+(i1-i2), and performs a subtraction operation on signal r3 of the first signal in time unit 3 and signal r4 in time unit 4 to obtain r3-r4=(a3*i3+i3)-(a4*i4+i4)=(a3*i3-a4*i4)+(i3-i4).

Since i1=i2=i3=i4, when the value of the first bit is 1, a1 and a2 are not equal, a3 and a4 are not equal, a1 and a4 are equal, and a2 and a3 are equal. For example, a1 is a signal of the ON symbol, a2 is a signal of the OFF symbol, a3 is a signal of the OFF symbol, and a4 is a signal of the ON symbol. At this time, r1-r2=a1*i1-a2*i2, r3-r4=a3*i3-a4*i4.

Correspondingly, when the value of the first bit is 0, a1 and a2 are not equal, a3 and a4 are not equal, a1 and a3 are equal, a2 and a4 are equal. For example, a1 is the OOK signal of the ON symbol, a2 is the OOK signal of the OFF symbol, a3 is the OOK signal of the ON symbol, and a4 is the OOK signal of the OFF symbol. At this time, r1-r2=a1*i1-a2*i2, r3-r4=a3*i3-a4*i4.

The network device can further perform a subtraction operation on (r1-r2) and (r3-r4). When the value of the first bit is 1, the result of the subtraction operation on (r1-r2) and (r3-r4) is (r1-r2)-(r3-r4)=a1*i1-a2*i2-(a3*i3-a4*i4)=2a1*i1;

When the value of the first bit is 0, the result of the subtraction operation on (r1-r2) and (r3-r4) is (r1-r2)-(r3-r4)=a1*i1-a2*i2-(a3*i3-a4*i4)=0. At this time, the network device can determine whether the value of the first bit is 0 or 1.

Alternatively, the network device may further perform a multiplication operation on (r1-r2) and (r3-r4). When the value of the first bit is 1, the result of the multiplication operation on (r1-r2) and (r3-r4) is (r1-r2)*(r3-r4)=(a1*i1-a2*i2)*(a3*i3-a4*i4)=-(a1*i1) ² ; when the value of the first bit is 0, the result of the multiplication operation on (r1-r2) and (r3-r4) is (r1-r2)*(r3-r4)=(a1*i1-a2*i2)*(a3*i3-a4*i4)=(a1*i1) ² . At this time, the network device can determine whether the value of the first bit is 0 or 1 according to whether the sign of the obtained result is positive or negative.

It can be seen from the above description that when the first terminal device sends the third signal to the second terminal device, the network device will also receive the third signal, and the third signal will interfere with the first signal sent by the second terminal device. Through the method adopted by this application, since the value of a bit in the first information is indicated by the difference information between the Z sub-signals in the second signal, when the network device demodulates the first signal modulated according to the second signal, it can use differential demodulation to eliminate the third signal in the received signal, thereby improving the robustness of the first signal sent by the second terminal device and improving the coverage performance of the first signal.

The above process mainly introduces the solution provided by the embodiment of the present application from the perspective of interaction between devices. It is understandable that in order to achieve the above functions, the terminal device and the network device may include hardware structures and/or software modules corresponding to the execution of each function. It should be easily appreciated by those skilled in the art that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the embodiments of the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present application.

The embodiment of the present application can divide the terminal device and the network device into functional units according to the above method example. For example, each functional unit can be divided according to each function, or two or more functions can be integrated into one unit. The above integrated unit can be implemented in the form of hardware or software functional unit.

Similar to the above concept, as shown in FIG10, the embodiment of the present application also provides a communication device 1000 for implementing the functions of the network device or the first terminal device or the second terminal device in the above method. For example, the device can be a software module or a chip system. In the embodiment of the present application, the chip system can be composed of a chip, or it can include a chip and other discrete devices. The communication device 1000 may include: a processing unit 1001 and a communication unit 1002.

In the embodiment of the present application, the communication unit may also be referred to as a transceiver unit, and may include a sending unit and/or a receiving unit, which are respectively used to execute the sending and receiving steps performed by the network device or the first terminal device or the second terminal device in the above method embodiment.

The communication device provided in the embodiment of the present application is described in detail below in conjunction with Figures 10 and 11. It should be understood that the description of the device embodiment corresponds to the description of the method embodiment, so the contents not described in detail can be referred to the method embodiment above, and for the sake of brevity, they will not be repeated here.

The communication unit may also be referred to as a transceiver, a transceiver, a transceiver device, etc. The processing unit may also be referred to as a processor, a processing board, a processing module, a processing device, etc. Optionally, the device used to implement the receiving function in the communication unit 1002 may be regarded as a receiving unit, and the device used to implement the sending function in the communication unit 1002 may be regarded as a sending unit, that is, the communication unit 1002 includes a receiving unit and a sending unit. The communication unit may also be sometimes referred to as a transceiver, a transceiver, or a transceiver circuit, etc. The receiving unit may also be sometimes referred to as a receiver, a receiver, or a receiving circuit, etc. The sending unit may also be sometimes referred to as a transmitter, a transmitter, or a transmitting circuit, etc.

In one implementation, the communication device 1000 may perform the following functions:

A communication unit, configured to receive a first signal from a second terminal device; the first signal is a signal obtained by modulating the second signal into a third signal, the second signal is used to carry first information, and the third signal comes from the first terminal device; a first bit in the first information corresponds to Z sub-signals in the second signal, the Z sub-signals are respectively located in different time units, and difference information between the Z sub-signals is used to indicate a value of the first bit, where Z is an integer greater than 1;

A processing unit is used to demodulate the first signal to obtain the first information.

A communication unit, configured to receive a third signal from the first terminal device;

a processing unit, configured to modulate the second signal into the third signal to obtain the first signal; the second signal is determined according to the first information, the first bit in the first information corresponds to Z sub-signals in the second signal, the Z sub-signals are respectively located in different time units, and the difference information between the Z sub-signals is used to indicate the value of the bit, and Z is an integer greater than 1;

The communication unit is used to send the first signal to the network device.

a communication unit, configured to receive first indication information from a network device, wherein the first indication information is used to indicate at least one of the following information: a modulation mode of the second signal; a modulation type of an orthogonal frequency division multiplexing OFDM symbol included in the third signal; a value of N, When the symbol type of the OFDM symbol is the second type, the OFDM symbol includes N parts; the length of the cyclic prefix of the OFDM symbol;

A processing unit is used to send the third signal to the second terminal device according to the first indication information through the communication unit.

The above are only examples, and the processing unit 1001 and the communication unit 1002 may also perform other functions. For a more detailed description, please refer to the relevant description in the method embodiment shown above, which will not be repeated here.

As shown in FIG11, a communication device 1100 provided in an embodiment of the present application is shown. The communication device shown in FIG11 may be a hardware circuit implementation of the communication device shown in FIG10. The communication device may be applicable to the flowchart shown above to perform the functions of the network device or the first terminal device or the second terminal device in the above method embodiment. For ease of explanation, FIG11 only shows the main components of the communication device.

As shown in Fig. 11, the communication device 1100 includes a processor 1110 and an interface circuit 1120. The processor 1110 and the interface circuit 1120 are coupled to each other. It can be understood that the interface circuit 1120 can be a transceiver or an input-output interface.

Optionally, the communication device 1100 may further include a memory 1130 for storing instructions executed by the processor 1110 or storing input data required for the processor 1110 to execute instructions or storing data generated after the processor 1110 executes instructions.

When the communication device 1100 is used to implement the method shown above, the processor 1110 is used to implement the function of the processing unit 1001, and the interface circuit 1120 is used to implement the function of the communication unit 1002.

It is understandable that the processor in the embodiments of the present application may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

In the embodiments of the present application, the processor may be a random access memory (RAM), a flash memory, a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a register, a hard disk, a mobile hard disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium may also be a component of the processor. The processor and the storage medium may be located in an ASIC. In addition, the ASIC may be located in a network device or a terminal device. The processor and the storage medium may also exist as discrete components in a network device or a terminal device.

An embodiment of the present application also provides a communication method, which includes the method executed by the network device in Figure 4.

An embodiment of the present application also provides a communication method, which includes the method executed by the first terminal device in Figure 4.

An embodiment of the present application also provides a communication method, which includes the method executed by the second terminal device in Figure 4.

An embodiment of the present application also provides a computer-readable storage medium for storing a computer program, wherein the computer program includes computer instructions for implementing the method performed by the network device in the above method embodiment, and/or the computer program includes computer instructions for implementing the method performed by the first terminal device in the above method embodiment, and/or the computer program includes computer instructions for implementing the method performed by the second terminal device in the above method embodiment.

For example, when the computer program is executed by a computer, the computer can implement the method performed by the first terminal device or the second terminal device or the network device in the above method embodiment.

An embodiment of the present application also provides a computer program product including a computer program code, which, when executed by a computer, enables the computer to implement the method executed by the first terminal device in the above method embodiment, and/or when executed by a computer, enables the computer to implement the method executed by the second terminal device in the above method embodiment, and/or when executed by a computer, enables the computer to implement the method executed by the network device in the above method embodiment.

An embodiment of the present application also provides a chip device, including a processor, for calling a computer program or computer instruction stored in the memory so that the processor executes the method executed by the network device in the embodiment shown in FIG. 4 above.

An embodiment of the present application also provides a chip device, including a processor, for calling a computer program or computer instruction stored in the memory so that the processor executes the method executed by the first terminal device in the embodiment shown in FIG. 4 above.

An embodiment of the present application also provides a chip device, including a processor, for calling a computer program or computer instruction stored in the memory so that the processor executes the method executed by the second terminal device in the embodiment shown in FIG. 4 above.

In a possible implementation, the input of the chip device corresponds to the receiving operation in the embodiment shown in FIG. 4 , and the output of the chip device corresponds to the sending operation in the embodiment shown in FIG. 4 .

Optionally, the processor is coupled to the memory via an interface.

Optionally, the chip device further comprises a memory, in which computer programs or computer instructions are stored.

An embodiment of the present application also provides a communication system, including a communication device for implementing the function of the first terminal device in the embodiment of Figure 4, a communication device for implementing the function of the second terminal device in the embodiment of Figure 4, and a communication device for implementing the function of the network device in the embodiment of Figure 4.

Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, optical storage, etc.) that contain computer-usable program code.

The present application is described with reference to the flowchart and/or block diagram of the method, device (system), and computer program product according to the present application. It should be understood that each process and/or box in the flowchart and/or block diagram, as well as the combination of the process and/or box in the flowchart and/or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one process or multiple processes in the flowchart and/or one box or multiple boxes in the block diagram.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device that implements the functions specified in one or more processes in the flowchart and/or one or more boxes in the block diagram.

Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

A communication method, comprising:

Receive a first signal from a second terminal device; the first signal is a signal obtained by modulating the second signal into a third signal, the second signal is used to carry first information, and the third signal comes from the first terminal device; a first bit in the first information corresponds to Z sub-signals in the second signal, the Z sub-signals are respectively located in different time units, and difference information between the Z sub-signals is used to indicate a value of the first bit, where Z is an integer greater than 1;

The first signal is demodulated to obtain the first information.
The method according to claim 1, characterized in that the third signal comprises at least one orthogonal frequency division multiplexing (OFDM) symbol;

The symbol type of the OFDM symbol is a first type, the OFDM symbol of the first type includes a first part, a second part and a third part, the second part is located between the first part and the third part, the signal corresponding to the first part is the same as the signal corresponding to the third part, and the duration corresponding to the first part is the same as the duration corresponding to the third part;

Alternatively, the symbol type of the OFDM symbol is a second type, the OFDM symbol of the second type includes N parts, the duration of each of the N parts is the same, the signal corresponding to each of the N parts of the OFDM symbol is the same, N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol.
The method according to claim 2, characterized in that the method further comprises:

The network device sends first indication information to the first terminal device, where the first indication information is used to indicate at least one of the following:

a modulation method of the second signal;

The symbol type of the OFDM symbol included in the third signal;

The value of N;

The length of the cyclic prefix of the OFDM symbol;

The frequency domain resource position occupied by the third signal;

The average transmission power of the third signal.
The method according to any one of claims 1 to 3, characterized in that the method further comprises:

Sending second indication information to the second terminal device, where the second indication information is used to indicate an information carrying mode of the second signal; the information carrying mode includes a first mode, a second mode and a third mode;

The information carrying mode is the first mode, the Z sub-signals of the second signal in the Z time units are used to indicate the value of one bit, and the Z time units are continuous in time;

The information carrying mode is the second mode, Z sub-signals of the second signal in Z time units are used to indicate a value of one bit, and the Z time units are discontinuous in time;

The information carrying mode is the third mode, and X+1 sub-signals of the second signal in X+1 time units are used to indicate values of X bits, where X is an integer greater than 1.
The method according to claim 4, wherein the Z time units are discontinuous in time, comprising:

There is an interval of M1 time units between two adjacent time units in the Z time units, where M1 is an integer greater than or equal to 1.
The method according to any one of claims 1 to 5, characterized in that the first information includes a second bit, and the first bit and the second bit are any two bits included in the first information;

The Z sub-signals corresponding to the first bit in the second signal are different from the Z sub-signals corresponding to the second bit in the second signal.
The method according to claim 6 is characterized in that the Z sub-signals corresponding to the first bit in the second signal are respectively located in Z time units, and two adjacent time units in the Z time units are separated by M2 time units, where M2 is an integer greater than or equal to 0.
The method according to claim 7 is characterized in that the third signal includes at least one OFDM symbol, and the Z time units corresponding to the first bit in the second signal are within the same OFDM symbol in the third signal.
The method according to any one of claims 1 to 5, characterized in that X bits in the first information correspond to X+1 sub-signals in the second signal, and the X+1 sub-signals are respectively located in X+1 time units, where X is an integer greater than 1;

The X+1 sub-signals include 1 common sub-signal and X unique sub-signals, and the common sub-signal is The X unique sub-signals correspond to the X bits one by one.
The method according to claim 9 is characterized in that the third signal includes at least one OFDM symbol, the X+1 time units are continuous in the time domain, and the X+1 time units are within the same OFDM symbol in the third signal.
The method according to any one of claims 1 to 10 is characterized in that the difference information between the Z sub-signals is an amplitude difference, an energy difference, or a phase difference between the Z sub-signals.
The method according to claim 11, characterized in that, if Z=2, the difference information between the Z sub-signals is the amplitude difference, energy difference, or phase difference between the first sub-signal and the second sub-signal of the two sub-signals;

If Z=4, the difference information between the Z sub-signals is the amplitude difference, energy difference, or phase difference between the first two sub-signals and the last two sub-signals in the four sub-signals.
A communication method, comprising:

receiving a third signal from the first terminal device;

The second terminal device modulates the second signal into the third signal to obtain the first signal; the second signal is determined according to the first information, the first bit in the first information corresponds to Z sub-signals in the second signal, the Z sub-signals are respectively located in different time units, and the difference information between the Z sub-signals is used to indicate the value of the bit, and Z is an integer greater than 1;

The first signal is sent to a network device.
The method according to claim 13, characterized in that the third signal comprises at least one orthogonal frequency division multiplexing (OFDM) symbol;

The symbol type of the OFDM symbol is a first type, the OFDM symbol of the first type includes a first part, a second part and a third part, the second part is located between the first part and the third part, the signal corresponding to the first part is the same as the signal corresponding to the third part, and the duration corresponding to the first part is the same as the duration corresponding to the third part;

Alternatively, the symbol type of the OFDM symbol is a second type, the OFDM symbol of the second type includes N parts, the duration of each of the N parts is the same, the signal corresponding to each of the N parts of the OFDM symbol is the same, N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol.
The method according to any one of claims 13 to 14, characterized in that the method further comprises:

receiving second indication information from the network device, where the second indication information is used to indicate an information carrying mode of the second signal; the information carrying mode includes a first mode, a second mode and a third mode;

The information carrying mode is the first mode, Z sub-signals of the second signal in Z time units are used to indicate a value of one bit, and the Z time units are continuous in time;

The information carrying mode is the second mode, Z sub-signals of the second signal in Z time units are used to indicate a value of one bit, and the Z time units are discontinuous in time;

The information carrying mode is the third mode, and X+1 sub-signals of the second signal in X+1 time units are used to indicate values of X bits, where X is an integer greater than 1.
The method according to claim 15, wherein the Z time units are discontinuous in time, comprising:

There is an interval of M1 time units between two adjacent time units in the Z time units, where M1 is an integer greater than or equal to 1.
The method according to any one of claims 13 to 16, characterized in that the first information includes a second bit, and the first bit and the second bit are any two bits included in the first information;

The Z sub-signals corresponding to the first bit in the second signal are different from the Z sub-signals corresponding to the second bit in the second signal.
The method according to claim 17 is characterized in that the Z sub-signals corresponding to the first bit in the second signal are respectively located in Z time units, and two adjacent time units in the Z time units are separated by M2 time units, where M2 is an integer greater than or equal to 0.
The method according to claim 18 is characterized in that the third signal includes at least one OFDM symbol, and the Z time units corresponding to the first bit in the second signal are within the same OFDM symbol in the third signal.
The method according to any one of claims 13 to 16, characterized in that X bits in the first information correspond to X+1 sub-signals in the second signal, and the X+1 sub-signals are respectively located in X+1 time units, where X is an integer greater than 1;

The X+1 sub-signals include 1 common sub-signal and X unique sub-signals, the common sub-signal corresponds to the X bits, and the X unique sub-signals correspond to the X bits one-to-one.
The method according to claim 20, characterized in that the third signal includes at least one OFDM symbol, the X+1 The X+1 time units are continuous in the time domain, and the X+1 time units are within the same OFDM symbol in the third signal.
The method according to any one of claims 13 to 21 is characterized in that the difference information between the Z sub-signals is an amplitude difference, an energy difference, or a phase difference between the Z sub-signals.
The method according to any one of claims 13 to 22, characterized in that the method further comprises:

Receive third indication information, where the third indication information is used to indicate at least one of the following:

a modulation method of the second signal;

The symbol type of the orthogonal frequency division multiplexing OFDM symbol included in the third signal;

A value of N, wherein when the symbol type of the OFDM symbol is the second type, the OFDM symbol includes N parts;

The length of the cyclic prefix of the OFDM symbol;

The frequency domain resource position occupied by the third signal;

The average transmission power of the third signal.
A communication method, comprising:

Receive first indication information from a network device, where the first indication information is used to indicate at least one of the following information: a modulation mode of a second signal; a modulation type of an orthogonal frequency division multiplexing OFDM symbol included in the third signal; a value of N, where when the symbol type of the OFDM symbol is the second type, the OFDM symbol includes N parts; and a length of a cyclic prefix of the OFDM symbol;

The third signal is sent to the second terminal device according to the first indication information.
The method according to claim 24, characterized in that the third signal is an excitation signal.
The method according to claim 24 or 25, characterized in that the third signal comprises at least one orthogonal frequency division multiplexing (OFDM) symbol;

The symbol type of the OFDM symbol is a first type, the OFDM symbol of the first type includes a first part, a second part and a third part, the second part is located between the first part and the third part, the signal corresponding to the first part is the same as the signal corresponding to the third part, and the duration corresponding to the first part is the same as the duration corresponding to the third part;

Alternatively, the symbol type of the OFDM symbol is a second type, the OFDM symbol of the second type includes N parts, the duration of each of the N parts is the same, the signal corresponding to each of the N parts of the OFDM symbol is the same, N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol.
A communication device, comprising:

A communication unit, configured to receive a first signal from a second terminal device; the first signal is a signal obtained by modulating the second signal into a third signal, the second signal is used to carry first information, and the third signal comes from the first terminal device; a first bit in the first information corresponds to Z sub-signals in the second signal, the Z sub-signals are respectively located in different time units, and difference information between the Z sub-signals is used to indicate a value of the first bit, where Z is an integer greater than 1;

A processing unit is used to demodulate the first signal to obtain the first information.
The apparatus according to claim 27, wherein the third signal comprises at least one orthogonal frequency division multiplexing (OFDM) symbol;

The symbol type of the OFDM symbol is a first type, the OFDM symbol of the first type includes a first part, a second part and a third part, the second part is located between the first part and the third part, the signal corresponding to the first part is the same as the signal corresponding to the third part, and the duration corresponding to the first part is the same as the duration corresponding to the third part;

Alternatively, the symbol type of the OFDM symbol is a second type, the OFDM symbol of the second type includes N parts, the duration of each of the N parts is the same, the signal corresponding to each of the N parts of the OFDM symbol is the same, N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol.
The device according to claim 28, characterized in that the communication unit is further used for:

Sending first indication information to the first terminal device, where the first indication information is used to indicate at least one of the following:

a modulation method of the second signal;

The symbol type of the OFDM symbol included in the third signal;

The value of N;

The length of the cyclic prefix of the OFDM symbol;

The frequency domain resource position occupied by the third signal;

The average transmission power of the third signal.
The device according to any one of claims 27 to 29, characterized in that the communication unit is further used for:

Sending second indication information to the second terminal device, where the second indication information is used to indicate an information carrying mode of the second signal; the information carrying mode includes a first mode, a second mode and a third mode;

The information carrying mode is the first mode, Z sub-signals of the second signal in Z time units are used to indicate a value of one bit, and the Z time units are continuous in time;

The information carrying mode is the second mode, Z sub-signals of the second signal in Z time units are used to indicate a value of one bit, and the Z time units are discontinuous in time;

The information carrying mode is the third mode, and X+1 sub-signals of the second signal in X+1 time units are used to indicate values of X bits, where X is an integer greater than 1.
The apparatus according to claim 30, wherein the Z time units are discontinuous in time and include:

There is an interval of M1 time units between two adjacent time units in the Z time units, where M1 is an integer greater than or equal to 1.
The device according to any one of claims 27 to 31, characterized in that the first information includes a second bit, and the first bit and the second bit are any two bits included in the first information;

The Z sub-signals corresponding to the first bit in the second signal are different from the Z sub-signals corresponding to the second bit in the second signal.
The device according to claim 32 is characterized in that the Z sub-signals corresponding to the first bit in the second signal are respectively located in Z time units, and two adjacent time units in the Z time units are separated by M2 time units, where M2 is an integer greater than or equal to 0.
The device according to claim 33 is characterized in that the third signal includes at least one OFDM symbol, and the Z time units corresponding to the first bit in the second signal are within the same OFDM symbol in the third signal.
The device according to any one of claims 27 to 34, characterized in that X bits in the first information correspond to X+1 sub-signals in the second signal, and the X+1 sub-signals are respectively located in X+1 time units, where X is an integer greater than 1;

The X+1 sub-signals include 1 common sub-signal and X unique sub-signals, the common sub-signal corresponds to the X bits, and the X unique sub-signals correspond to the X bits one-to-one.
The device according to claim 35 is characterized in that the third signal includes at least one OFDM symbol, the X+1 time units are continuous in the time domain, and the X+1 time units are within the same OFDM symbol in the third signal.
The device according to any one of claims 27 to 36 is characterized in that the difference information between the Z sub-signals is an amplitude difference, an energy difference, or a phase difference between the Z sub-signals.
The device according to claim 37, characterized in that, if Z=2, the difference information between the Z sub-signals is the amplitude difference, energy difference, or phase difference between the first sub-signal and the second sub-signal of the two sub-signals;

If Z=4, the difference information between the Z sub-signals is the amplitude difference, energy difference, or phase difference between the first two sub-signals and the last two sub-signals in the four sub-signals.
A communication device, comprising:

A communication unit, configured to receive a third signal from the first terminal device;

a processing unit, configured to modulate the second signal into the third signal to obtain the first signal; the second signal is determined according to the first information, the first bit in the first information corresponds to Z sub-signals in the second signal, the Z sub-signals are respectively located in different time units, and the difference information between the Z sub-signals is used to indicate the value of the bit, and Z is an integer greater than 1;

The communication unit is used to send the first signal to the network device.
The apparatus according to claim 39, wherein the third signal comprises at least one orthogonal frequency division multiplexing (OFDM) symbol;

The symbol type of the OFDM symbol is a first type, the OFDM symbol of the first type includes a first part, a second part and a third part, the second part is located between the first part and the third part, the signal corresponding to the first part is the same as the signal corresponding to the third part, and the duration corresponding to the first part is the same as the duration corresponding to the third part;

Alternatively, the symbol type of the OFDM symbol is a second type, the OFDM symbol of the second type includes N parts, the duration of each of the N parts is the same, the signal corresponding to each of the N parts of the OFDM symbol is the same, N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol.
The device according to any one of claims 39 to 40, characterized in that the communication unit is further used for:

receiving second indication information from the network device, where the second indication information is used to indicate an information carrying mode of the second signal; the information carrying mode includes a first mode, a second mode and a third mode;

The information carrying mode is the first mode, Z sub-signals of the second signal in Z time units are used to indicate a value of one bit, and the Z time units are continuous in time;

The information carrying mode is the second mode, Z sub-signals of the second signal in Z time units are used to indicate a value of one bit, and the Z time units are discontinuous in time;

The information carrying mode is the third mode, and X+1 sub-signals of the second signal in X+1 time units are used to indicate values of X bits, where X is an integer greater than 1.
The apparatus according to claim 41, wherein the Z time units are discontinuous in time and include:

There is an interval of M1 time units between two adjacent time units in the Z time units, where M1 is an integer greater than or equal to 1.
The device according to any one of claims 39 to 42, characterized in that the first information includes a second bit, and the first bit and the second bit are any two bits included in the first information;

The Z sub-signals corresponding to the first bit in the second signal are different from the Z sub-signals corresponding to the second bit in the second signal.
The device according to claim 43 is characterized in that the Z sub-signals corresponding to the first bit in the second signal are respectively located in Z time units, and two adjacent time units in the Z time units are separated by M2 time units, where M2 is an integer greater than or equal to 0.
The device according to claim 44 is characterized in that the third signal includes at least one OFDM symbol, and the Z time units corresponding to the first bit in the second signal are within the same OFDM symbol in the third signal.
The device according to any one of claims 39 to 45, characterized in that X bits in the first information correspond to X+1 sub-signals in the second signal, and the X+1 sub-signals are respectively located in X+1 time units, where X is an integer greater than 1;

The X+1 sub-signals include 1 common sub-signal and X unique sub-signals, the common sub-signal corresponds to the X bits, and the X unique sub-signals correspond to the X bits one-to-one.
The device according to claim 46 is characterized in that the third signal includes at least one OFDM symbol, the X+1 time units are continuous in the time domain, and the X+1 time units are within the same OFDM symbol in the third signal.
The device according to any one of claims 39 to 47 is characterized in that the difference information between the Z sub-signals is the amplitude difference, energy difference or phase difference between the Z sub-signals.
The device according to any one of claims 39 to 48, characterized in that the communication unit is further used for:

Receive third indication information, where the third indication information is used to indicate at least one of the following:

a modulation method of the second signal;

The symbol type of the orthogonal frequency division multiplexing OFDM symbol included in the third signal;

A value of N, wherein when the symbol type of the OFDM symbol is the second type, the OFDM symbol includes N parts;

The length of the cyclic prefix of the OFDM symbol;

The frequency domain resource position occupied by the third signal;

The average transmission power of the third signal.
A communication device, comprising:

A communication unit, configured to receive first indication information from a network device, wherein the first indication information is used to indicate at least one of the following information: a modulation mode of a second signal; a modulation type of an orthogonal frequency division multiplexing OFDM symbol included in the third signal; a value of N, wherein when the symbol type of the OFDM symbol is the second type, the OFDM symbol includes N parts; and a length of a cyclic prefix of the OFDM symbol;

A processing unit is used to send the third signal to the second terminal device according to the first indication information through the communication unit.
The device according to claim 50 is characterized in that the third signal is an excitation signal.
The device according to claim 50 or 51, characterized in that the third signal includes at least one orthogonal frequency division multiplexing (OFDM) symbol;

The symbol type of the OFDM symbol is a first type, the OFDM symbol of the first type includes a first part, a second part and a third part, the second part is located between the first part and the third part, the signal corresponding to the first part is the same as the signal corresponding to the third part, and the duration corresponding to the first part is the same as the duration corresponding to the third part;

Alternatively, the symbol type of the OFDM symbol is a second type, the OFDM symbol of the second type includes N parts, the duration of each of the N parts is the same, the signal corresponding to each of the N parts of the OFDM symbol is the same, N is an integer greater than 1; the total duration of the N parts is equal to the length of the OFDM symbol.
A communication device, comprising a processor and a memory;

The processor is used to execute the computer program or instructions stored in the memory, so that the communication device implements the method described in any one of claims 1 to 26.
A computer-readable storage medium, characterized in that a computer program or instruction is stored therein, and when the computer program or instruction is executed on a computer, the computer implements the method according to any one of claims 1 to 26.
A chip, characterized in that it includes a processor, wherein the processor is coupled to a memory and is used to execute a computer program or instruction stored in the memory, so that the chip implements the method described in any one of claims 1 to 26.
A computer program product, characterized in that when a computer reads and executes the computer program product, the computer executes the method according to any one of claims 1 to 26.