WO2016123776A1

WO2016123776A1 - Data transmission method and apparatus

Info

Publication number: WO2016123776A1
Application number: PCT/CN2015/072316
Authority: WO
Inventors: 韩广林; 刘洋; 熊新; 屈银翔
Original assignee: 华为技术有限公司
Priority date: 2015-02-05
Filing date: 2015-02-05
Publication date: 2016-08-11
Also published as: CN106233639A; CN106233639B

Abstract

Disclosed are a data transmission method and apparatus, which fall within the technical field of wireless communications. The method comprises: according to information about a channel, determining a maximum data receiving rate of each relay device; according to the maximum data receiving rate of each relay device, determining a data transmitting rate of a source node; according to the data transmitting rate of the source node, determining a target relay device; and in a first time slot, sending data to a target node and the target relay device by employing the data transmitting rate of the source node. The data transmitting rate of the source node in the present invention does not simply depend on a channel gain of one relay device but is determined by the maximum data receiving rate of the relay device determined by the channel information, so that on the premise of guaranteeing a relatively high data transmitting rate of the source node, multiple relay devices can participate in a cooperative transmission process as much as possible, such that the diversity gain and the channel capacity are relatively high, and the frequency spectrum utilization rate is increased.

Description

Data transmission method and device

Technical field

The present invention relates to the field of wireless communication technologies, and in particular, to a data transmission method and apparatus.

Background technique

With the development of wireless communication technologies, the source node receives a large amount of data sent by multiple user equipments. However, in many cases, the source node and the core network are not interconnected by wired fiber, but need to transmit data through the wireless device. For example, in a temporary hotspot (such as a stadium, a theater, etc.), after receiving the massive data sent by the user equipment, the source node needs to transmit the massive data sent by the user equipment to the target through the backhaul link (Back haul). The node transmits the massive data sent by the user equipment to the core network by means of the wired fiber connected to the target node. Due to the long distance between the source node and the target node, the data is lost during transmission, making it difficult for the target node to successfully decode the received data. In order to solve this problem, cooperative transmission is often performed by means of a relay device.

The related technology combines multiple relay devices into one multicast group. Based on the multicast group, the following two methods are used for data transmission:

The first mode: the source node selects the worst channel gain from the channel gains of each relay device in the multicast group, and determines the data transmission rate according to the worst channel gain, and then sends the data separately by using the transmission rate. Give the target node and each relay device in the multicast group. When the target node receives the data sent by the source node, it does not directly decode the data, but stores the data. When receiving the data sent by the source node, each relay device in the multicast group decodes the received data, and encodes the decoded data according to the original coding mode or a new coding mode to obtain modulated data. The modulated data is then sent to the target node. The target node combines and decodes the data sent by the source node and the modulated data sent by each relay device.

The second mode: the source node selects the optimal information from the channel gains of the relay devices in the multicast group. The channel gain is determined according to the optimal channel gain, and the data is transmitted to the target node and each relay device in the multicast group by using the data transmission rate. When the target node receives the data sent by the source node, it does not directly decode the data, but stores the data. When receiving the data sent by the source node, the relay device corresponding to the optimal channel gain in the multicast group decodes the received data, and performs the decoded data according to the original coding mode or a new coding mode. Encoding, obtaining modulated data, and then transmitting the modulated data to the target node. The target node combines and decodes the data sent by the source node and the modulated data sent by the relay device corresponding to the optimal channel gain.

In the process of implementing the present invention, the inventors have found that the related art has at least the following problems:

In the first mode, the data transmission rate of the source node is determined by the worst channel gain in the multicast group, and the transmission rate is small. Each relay device in the multicast group participates in data transmission, and the diversity gain is large, but the channel capacity is Smaller, spectrum utilization is lower.

In the second mode, the transmission rate of the source node is determined by the optimal channel gain in the multicast group, and the transmission rate is large, and the channel capacity is large, but the relay device participating in the coordinated transmission in the multicast group is only the optimal channel. The relay device corresponding to the gain has a small grading gain and a low spectrum utilization rate.

Summary of the invention

In order to solve the problem of the related art, an embodiment of the present invention provides a data transmission method and apparatus. The technical solution is as follows:

In a first aspect, a data transmission apparatus is provided, the apparatus comprising:

a receiving rate determining module, configured to determine a maximum data receiving rate of each relay device according to channel information, where the channel information includes a channel gain of the source node and the target node, and a channel gain of the source node and each relay device a channel gain of each relay device and the target node, a data transmission power of the source node, a data transmission power of the relay device, and a Gaussian white noise power of the relay device;

a transmission rate determining module, configured to determine a data transmission rate of the source node according to a maximum data receiving rate of each relay device;

a device determining module, configured to determine a target relay device according to a data transmission rate of the source node;

a sending module, configured to send data to the target node and the target relay device by using a data transmission rate of the source node in a first time slot, where the target relay device is in a second time slot The data is processed to obtain modulated data, and the modulated data is transmitted to the target node.

In conjunction with the first aspect, in a first possible implementation manner of the first aspect, the device further includes:

An obtaining module, configured to acquire a channel gain of the source node and each relay device;

a sorting module, configured to sort the channel gain of the source node and each relay device from large to small;

a numbering module, configured to number the relay devices corresponding to the channel gain from small to large according to the channel gain order result;

The receiving rate determining module is configured to determine a maximum data receiving rate of each relay device one by one according to the relay device number.

With reference to the first aspect, in a second possible implementation manner of the first aspect, the maximum data receiving rate of each of the relay devices determined by the receiving rate determining module is:

Wherein, V _i is the maximum data receiving rate of the i-th relay device,

The data reception rate of the i-th relay device in the first time slot,

For the sum of the data transmission rates of the first to the ith relay devices in the second time slot, N is the number of relay devices, P is the data transmission power of the source node, and P' is the data of the relay device. Transmit power,

For the channel gain of the source node and the i-th relay device, |h _Sd | ² is the channel gain of the source node and the target node,

For the channel gain of the i-th relay device and the target node, N ₀ is the Gaussian white noise power of the relay device.

In conjunction with the second possible implementation of the first aspect, a third possible implementation in the first aspect In the mode, the data transmission rate of the source node determined by the transmission rate determining module is:

Where R is the data transmission rate of the source node.

With reference to the first aspect, in a fourth possible implementation manner of the first aspect, the device determining module is configured to obtain a data receiving rate of each relay device in a first time slot; The data reception rate in one slot is compared with the data transmission rate of the source node; the relay device in which the data reception rate in the first slot is not less than the data transmission rate of the source node is used as the target relay device.

In a second aspect, a data transmission method is provided, the method comprising:

Determining, according to channel information, a maximum data reception rate of each relay device, the channel information including a channel gain of the source node and the target node, a channel gain of the source node and each relay device, and each relay device a channel gain of the target node, a data transmission power of the source node, a data transmission power of the relay device, and a Gaussian white noise power of the relay device;

Determining a data transmission rate of the source node according to a maximum data receiving rate of each relay device;

Determining a target relay device according to a data transmission rate of the source node;

Transmitting data to the target node and the target relay device by using a data transmission rate of the source node in a first time slot, and processing, by the target relay device, the data in a second time slot And obtaining modulated data, and transmitting the modulated data to the target node.

With reference to the second aspect, in a first possible implementation manner of the second aspect, before the determining, according to the channel information, the maximum data receiving rate of each of the relay devices, the method further includes:

Obtaining a channel gain of the source node and each relay device;

Sorting the channel gain of the source node and each relay device from large to small;

According to the channel gain order result, the relay devices corresponding to the channel gain are numbered from small to large;

Determining, according to the channel information, a maximum data receiving rate of each relay device, including:

The maximum data reception rate of each relay device is determined one by one according to the relay device number.

With reference to the second aspect, in a second possible implementation manner of the second aspect, the determining, by the channel information, the maximum data receiving rate of each of the relay devices is:

Wherein, V _i is the maximum data receiving rate of the i-th relay device,

The data reception rate of the i-th relay device in the first time slot,

With reference to the second possible implementation of the second aspect, in a third possible implementation manner of the second aspect, the determined data transmission rate of the source node is determined according to a maximum data receiving rate of each relay device. :

Where R is the data transmission rate of the source node.

With reference to the second aspect, in a fourth possible implementation manner of the second aspect, determining the target relay device according to the data transmission rate of the source node includes:

Obtaining a data receiving rate of each relay device in the first time slot;

Comparing the data reception rate of each relay device in the first time slot with the data transmission rate of the source node;

A relay device having a data reception rate not less than a data transmission rate of the source node in the first time slot is used as a target relay device.

The beneficial effects brought by the technical solutions provided by the embodiments of the present invention are:

The source node determines the maximum data receiving rate of each relay device according to the channel information, and determines the data transmission rate of the source node according to the maximum data receiving rate of each relay device, thereby determining the target relay device, and then determining the target relay device. Transmitting data to the target node and the target relay device by using the data transmission rate of the source node in the first time slot, the target relay device processes the data in the second time slot, and sends the processed data to Target node. Since the data transmission rate of the source node in the present invention is not simply determined by the channel gain of a certain relay device, the maximum data reception rate of the relay device determined by the channel information is determined, thereby ensuring a higher data transmission rate. Under the premise of large, as many relay devices as possible participate in the coordinated transmission process, so that the diversity gain and channel capacity are large, and the spectrum utilization rate is improved.

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention. Other drawings may also be obtained from those of ordinary skill in the art in light of the inventive work.

1 is a schematic diagram of an implementation environment involved in a data transmission method according to an embodiment of the present invention;

2 is a schematic structural diagram of a data transmission apparatus according to an embodiment of the present invention;

3 is a schematic structural diagram of a data transmission apparatus according to another embodiment of the present invention;

4 is a flowchart of a data transmission method according to another embodiment of the present invention;

FIG. 5 is a flowchart of a data transmission method according to another embodiment of the present invention; FIG.

6 is a schematic diagram of multi-relay cooperative transmission for a wireless backhaul link according to another embodiment of the present invention;

FIG. 7 is a schematic diagram of comparison of spectrum efficiency provided by another embodiment of the present invention.

detailed description

The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

With the development of wireless communication technology, the number of user equipment has increased, and the amount of data transmission has also increased accordingly. In the existing data transmission system, the distance between the source node and the target node is relatively long, and is limited by the transmission power and transmission bandwidth of the source node, and the loss in the data transmission process, and the target node receives the data source. When data is sent by a node, the received data is often not successfully decoded. In order to improve the decoding success rate of the target node, at present, when performing data transmission, cooperative transmission is often performed by means of multiple relay devices. FIG. 1 is a schematic diagram of an implementation environment of coordinated transmission of multiple relay devices according to an embodiment of the present invention. The implementation environment includes a source node, a relay device, and a target node. The source node may be a data source base station or the like in the wireless communication cell, and the target node may be an aggregate base station in the wireless communication cell. The source node has a function of transmitting and transmitting data, and the relay device has a function of transmitting, decoding, and forwarding data, and the target node has a function of combining and decoding data. In all embodiments of the invention, the source node, the relay device, and the target node are all single antenna configurations and operate in a half duplex mode.

An embodiment of the present invention provides a data transmission apparatus for performing the data transmission method described in FIG. 4 or FIG. 5 described below. Referring to FIG. 2, the apparatus includes:

The receiving rate determining module 201 is configured to determine, according to the channel information, a maximum data receiving rate of each relay device, where the channel information includes a channel gain of the source node and the target node, a channel gain of the source node and each relay device, and each Channel gain of the relay device and the target node, data transmission power of the source node, data transmission power of the relay device, and Gaussian white noise power of the relay device;

a transmission rate determining module 202, configured to determine a data transmission rate of the source node according to a maximum data receiving rate of each relay device;

The device determining module 203 is configured to determine a target relay device according to a data transmission rate of the source node.

The sending module 204 is configured to send data to the target node and the target relay device by using a data transmission rate of the source node in the first time slot, and process the data in the second time slot by the target relay device to obtain modulated data. , the modulated data is sent to the target node.

In another embodiment of the present invention, the apparatus further includes:

An obtaining module, configured to obtain a channel gain of the source node and each relay device;

In another embodiment of the present invention, the maximum data receiving rate of each relay device determined by the receiving rate determining module 201 is:

Wherein, V _i is the maximum data receiving rate of the i-th relay device, The data reception rate of the i-th relay device in the first time slot,

For the sum of the data transmission rates of the first to the ith relay devices in the second time slot, N is the number of relay devices, P is the data transmission power of the source node, and P' is the data transmission power of the relay device. ,

In another embodiment of the present invention, the data transmission rate of the source node determined by the transmission rate determination module 202 is:

Where R is the data transmission rate of the source node.

In another embodiment of the present invention, the device determining module 203 is configured to obtain a data receiving rate of each relay device in a first time slot; and a data receiving rate and a source of each relay device in the first time slot. The data transmission rate of the node is compared; a relay device whose data reception rate is not less than the data transmission rate of the source node in the first time slot is used as the target relay device.

The device provided by the embodiment of the present invention determines the maximum data receiving rate of each relay device according to the channel information, and determines the data transmission rate of the source node according to the maximum data receiving rate of each relay device, thereby determining the data transmission rate of the source node. a target relay device, after which the data is transmitted to the target node and the target relay device by using the data transmission rate of the source node in the first time slot, and the target relay device processes the data in the second time slot, and The processed data is sent to the target node. Since the data transmission rate of the source node in the present invention is not simply determined by the channel gain of a certain relay device, the maximum data reception rate of the relay device determined by the channel information is determined, thereby ensuring a higher data transmission rate. Under the premise of large, as many relay devices as possible participate in the coordinated transmission process, so that the diversity gain and channel capacity are large, and the spectrum utilization rate is improved.

The embodiment of the invention provides a data transmission device. Referring to FIG. 3, the device includes a processor 301 and a transmitter 302.

The processor 301 is configured to determine, according to the channel information, a maximum data receiving rate of each relay device, where the channel information includes a channel gain of the source node and the target node, a channel gain of the source node and each relay device, and each Channel gain of the relay device and the target node, data transmission power of the source node, data transmission power of the relay device, and Gaussian white noise power of the relay device;

The processor 301 is further configured to determine a data transmission rate of the source node according to a maximum data receiving rate of each relay device.

The processor 301 is further configured to determine, according to a data transmission rate of the source node, a target relay device;

The transmitter 302 is further configured to send data to the target node and the target relay device by using a data transmission rate of the source node in the first time slot, and the target relay device processes the data in the second time slot to obtain modulation. Data, the modulated data is sent to the target node.

In another embodiment of the present invention, the processor 301 is further configured to acquire channel gains of the source node and each of the relay devices; sort the channel gains of the source node and each of the relay devices from large to small; As a result of the gain sequence, the relay devices corresponding to the channel gains are numbered from small to large; the processor 301 is further configured to determine the maximum data receiving rate of each of the relay devices one by one according to the relay device number.

In another embodiment of the present invention, the maximum data reception rate of each relay device determined by the processor 301 is:

Wherein, V _i is the maximum data receiving rate of the i-th relay device,

The data reception rate of the i-th relay device in the first time slot,

In another embodiment of the present invention, the data transmission rate of the source node determined by the processor 301 is:

Where R is the data transmission rate of the source node.

In another embodiment of the present invention, the processor 301 is further configured to acquire a data receiving rate of each relay device in the first time slot; and receive a data receiving rate and a source node of each relay device in the first time slot. The data transmission rate of the point is compared; a relay device whose data reception rate is not less than the data transmission rate of the source node in the first time slot is used as the target relay device.

The embodiment of the present invention provides a data transmission method. Referring to FIG. 4, the method process provided by the embodiment of the present invention includes:

401. Determine, according to channel information, a maximum data receiving rate of each relay device, where the channel information includes a channel gain of the source node and the target node, a channel gain of the source node and each relay device, and each relay device and target. The channel gain of the node, the data transmission power of the source node, the data transmission power of the relay device, and the Gaussian white noise power of the relay device.

402. Determine a data transmission rate of the source node according to a maximum data receiving rate of each relay device.

403. Determine a target relay device according to a data transmission rate of the source node.

404. The data is sent to the target node and the target relay device by using the data transmission rate of the source node in the first time slot, and the data is processed by the target relay device in the second time slot to obtain modulated data, and the modulated data is modulated. Send to the target node.

According to the method provided by the embodiment of the present invention, the source node determines the maximum data receiving rate of each relay device according to the channel information, and determines the source node according to the maximum data receiving rate of each relay device. The data transmission rate, and then the target relay device is determined, and then, in the first time slot, the data transmission rate of the source node is used to transmit data to the target node and the target relay device, and the target relay device is in the second time slot. The data is processed and the processed data is sent to the target node. Since the data transmission rate of the source node in the present invention is not simply determined by the channel gain of a certain relay device, the maximum data reception rate of the relay device determined by the channel information is determined, thereby ensuring a higher data transmission rate. Under the premise of large, as many relay devices as possible participate in the coordinated transmission process, so that the diversity gain and channel capacity are large, and the spectrum utilization rate is improved.

In another embodiment of the present invention, before determining the maximum data receiving rate of each relay device according to the channel information, the method further includes:

Obtaining the channel gain of the source node and each relay device;

Determine the maximum data reception rate of each relay device based on the channel information, including:

In another embodiment of the present invention, the maximum data reception rate of each relay device determined according to the channel information is:

Wherein, V _i is the maximum data receiving rate of the i-th relay device,

The data reception rate of the i-th relay device in the first time slot,

In another embodiment of the present invention, the determined data transmission rate of the source node is based on the maximum data reception rate of each relay device:

Where R is the data transmission rate of the source node.

In another embodiment of the present invention, determining the target relay device according to the data transmission rate of the source node includes:

Obtaining a data receiving rate of each relay device in the first time slot;

A relay device in which the data reception rate in the first time slot is not less than the data transmission rate of the source node is used as the target relay device.

All of the above optional technical solutions may be used in any combination to form an optional embodiment of the present invention, and will not be further described herein.

With reference to the implementation environment shown in FIG. 1 , the embodiment of the present invention provides a method for number transmission. Referring to FIG. 5 , the process of the method provided in this embodiment includes:

501. The source node determines a maximum data receiving rate of each relay device according to the channel information.

In the field of wireless communication, each relay device has a maximum data reception rate, which is a basis for the relay device to successfully decode the received data. When the data transmission rate of the source node is greater than the maximum data reception rate of the relay device, the relay device cannot successfully decode the received data; when the data transmission rate of the source node is smaller than the maximum data reception rate of the relay device, The relay device can successfully decode the received data, and after the relay device successfully decodes the received data, the relay device can participate in the data transmission, that is, the data transmission rate and the relay of the source node. The maximum data reception rate of the device itself determines which relay devices can perform coordinated transmission. The number of relay devices participating in coordinated transmission in the scenario of coordinated transmission of multiple relay devices The quantity directly affects the diversity gain of the data transmission system, which in turn affects the spectrum utilization. Therefore, in order to improve the spectrum utilization, the data transmission method provided in this embodiment also needs to determine the maximum data reception rate of each relay device.

In the field of wireless communication, channel information can accurately reflect the actual communication status of each device in the data transmission system, and the actual communication status of each device in the data transmission system directly determines the maximum data reception rate of the relay device. When determining the maximum data receiving rate of each relay device, the node may first obtain channel information of the data transmission system, and then determine a maximum data receiving rate of each relay device according to the acquired channel information. The channel information includes at least a channel gain of the source node and the target node, a channel gain of the source node and each relay device, a channel gain of each relay device and the target node, a data transmission power of the source node, and a relay device. Data transmission power and Gaussian white noise power of the relay device. Channel gain is used as a channel coefficient to describe the attenuation and fading characteristics of a channel. Gaussian white noise is a kind of noise form that is subjected to Gaussian distribution and power density is evenly distributed. In this embodiment, the channel information is stored in the storage unit of the source node, and the channel information is obtained through testing. Therefore, when acquiring the channel information, the source node can directly obtain from the corresponding storage unit.

In order to facilitate management of the maximum data reception rate of multiple relay devices, the source node obtains the source node and each relay from the channel information before determining the maximum data reception rate of each relay device according to the channel information. The channel gain of the device, and the channel gain of the source node and each relay device are sorted from large to small, and the channel gain ranking result is obtained, and based on the channel gain order result, the relay device corresponding to the channel gain is small to large. Numbered.

For example, the relay devices in the data transmission system are the relay device A, the relay device B, the relay device C, and the relay device D. If the channel gain of the source node and the relay device A is 10 dB, the source node and the relay The channel gain of the device B is 20 dB, the channel gain of the source node and the relay device C is 15 dB, and the channel gain of the source node and the relay device D is 25 dB, and the channel gain of the source node and each relay device is as large as The small ordering is: 25dB, 20dB, 15dB, 10dB. According to the channel gain order result, the relay devices corresponding to the channel gain are numbered from small to large, and the number that can be set for the relay device D is 1. The number set for the relay device B is 2, the number set for the relay device C is 3, and the number set for the relay device A is 4.

Based on the number set for each relay device, the source node determines the maximum data reception rate of each relay device according to the channel information, and can determine one by one according to the relay device number. For example, the relay device in the data transmission system is the relay device A, the relay device B, and the relay device C. The number of the relay device A is 2, the number of the relay device B is 1, and the number of the relay device C is If the value is 3, the maximum data receiving rate of each relay device is determined according to the number of each relay device. The maximum data receiving rate of the relay device B is determined first, and then the maximum data receiving rate of the relay device A is determined. Finally, the maximum data reception rate of the relay device C is determined.

In the coordinated transmission scenario, the data from the source node to the target node will experience two levels of hopping. In the embodiment, the process of sending the data to the relay device by the source node is called a first hop, and the relay device forwards the data to the target node. The process is called the second level jump. In this process, the time slot used when the source node transmits data is referred to as a first time slot, and the time slot used when the target relay device transmits data is referred to as a second time slot. The first time slot and the second time slot may be two consecutive time slots, or may be two consecutive time slots, which is not specifically limited in this embodiment.

In the process of two-level hopping of data from the source node to the target node, the channel capacity of the source node to a certain relay node and the channel capacity of the relay node to the target node are often different. The maximum capacity of the source node to a certain relay channel does not mean that the channel capacity of the relay to the target node is also the largest. In the first time slot, if the rate at which the source node sends data is greater than the channel capacity of it and a certain relay, the relay cannot successfully decode the data sent by the source node. In the second time slot, the data received by the target node is the channel capacity sum from multiple relays. If the data rate transmitted by the source node is greater than the channel capacity sum of all selected target relays to the target node, the target node cannot correctly decode the data. Therefore, in order to be able to successfully transmit data, in determining the maximum data reception rate of each relay device, the minimum rate of the two-level hop is required as the maximum data reception rate of the relay device. In the specific implementation of the process, the following formula (1) can be employed.

Wherein, V _i is the maximum data receiving rate of the i-th relay device,

The data reception rate of the i-th relay device in the first time slot,

For example, the relay device in the data transmission system is the relay device A, the relay device B, the relay device C, the relay device D, and the relay device E. According to the channel information, in the first level hop, the source node determines The data receiving rate of the relay device A in the first time slot is 2, the data receiving rate of the relay device B in the first time slot is 4, and the data receiving rate of the relay device C in the first time slot is 5, The data receiving rate of the device D in the first time slot is 6, and the data receiving rate of the relay device E in the first time slot is 7. In the second level hop, the source node determines that the relay device A is in the second time. The sum of the data transmission rates of the slots is 4, the sum of the data transmission rates of the relay device B in the second time slot is 7, and the sum of the data transmission rates of the relay device C in the second time slot is 8, the relay device D The sum of the data transmission rates of the second time slot is 9, and the sum of the data transmission rates of the relay device E in the second time slot is 10, and finally the maximum data reception rate of the relay device A can be determined to be 2, The maximum data reception rate of device B is 4, the maximum data reception rate of relay device C is 5, and the maximum of relay device D is 6 is a data reception rate, the maximum rate of data reception to the relay device E 7.

502. The source node determines a data transmission rate of the source node according to a maximum data receiving rate of each relay device.

In order to improve the spectrum utilization rate, after determining the maximum data receiving rate of each relay device according to the channel information, the source node also determines the source node according to the maximum data receiving rate of each relay device. The data transmission rate of the source node is the data transmission rate used by the source node to transmit data during data transmission.

In addition, in the field of wireless communication, the data transmission rate of the source node has an important influence on the diversity gain of the data transmission system. When the data transmission rate of the source node is small, the number of relay devices successfully decoded by the source node is more. The more the number of relay devices participating in data cooperative transmission, the greater the diversity gain of the data transmission system in the second time slot. When the data transmission rate of the source node is large, the data transmitted by the source node is successfully decoded. The fewer the number of devices, the less the number of relay devices participating in data cooperative transmission, and the diversity gain of the data transmission system in the second time slot is small. Therefore, when determining the data transmission rate of the source node according to the maximum data receiving rate of each relay device, the source node traverses the data receiving rate of all the relay devices and selects the maximum data receiving rate of all the relay devices. The larger value is used as the data transmission rate of the source node. In practical applications, the maximum value can be selected from the maximum data reception rate of all relay devices as the data transmission rate of the source node. In the specific implementation of the process, the following formula (2) can be employed.

Where R is the data transmission rate of the source node.

For example, the relay device in the data transmission system is the relay device A, the relay device B, the relay device C, the relay device D, and the relay device E. According to the channel information, the source node determines the maximum of the relay device A. The data receiving rate is 2, the maximum data receiving rate of the relay device B is 3, the maximum data receiving rate of the relay device C is 4, the maximum data receiving rate of the relay device D is 5, and the maximum data receiving of the relay device E is The rate is 6, and since the maximum data reception rate of the relay device E is the largest among the maximum data reception rates of all the relay devices, it can be determined that the data transmission rate of the source node of the source node is 6.

The above takes the maximum data receiving rate selected by all the relay devices as the data transmission rate of the source node. In practical applications, a threshold range may also be set, and the difference between the selected maximum data receiving rate and the selected data receiving rate may be The data reception rate within the preset range is used as the data transmission rate of the source node.

503. The source node determines the target relay device according to the data transmission rate of the source node.

The target relay device is a relay device that participates in data transmission during data transmission. In this embodiment, when determining the target relay device according to the data transmission rate of the source node, the data receiving rate of each relay device in the first time slot may be acquired first, and each relay device is in the first time slot. The data reception rate in the first node is compared with the data transmission rate of the source node, and the relay device whose data reception rate is not less than the data transmission rate of the source node in the first time slot is used as the target relay device. For example, the relay device in the data transmission system is the relay device A, the relay device B, the relay device C, the relay device D, and the relay device E. According to the channel information, the source node determines that the relay device A is in the first The data reception rate of one slot is 2, the data reception rate of the relay device B in the first slot is 4, the data reception rate of the relay device C in the first slot is 5, and the relay device D is at the first time. The data receiving rate of the slot is 6, and the data receiving rate of the relay device E in the first time slot is 7. If the maximum data receiving rate of each relay device in the data transmission system is determined, the data transmission rate of the source node is determined as 6. The relay device D and the relay device E are used as target relay devices.

This process can be determined by formula (3) when it is implemented.

Where L ^* is the number of target relay devices.

It should be noted that the foregoing steps 501 to 503 are processes for determining the data transmission rate of the data transmitted by the source node and determining the relay device participating in the coordinated transmission, and the process does not need to be repeatedly executed in each data transmission process, only at the source. The channel information acquired by the node changes, that is, the channel gain of the source node and the target node, the channel gain of the source node and each relay device, the channel gain of each relay device and the target node, and the data transmission power of the source node, When at least one of the data transmission power of the device and the Gaussian white power of the relay device changes, the above steps 501 to 503 are re-executed.

504. The source node sends data to the target node and the target relay device by using a data transmission rate of the source node in the first time slot.

In order to enable the user to obtain the corresponding service, when the source node side has data to transmit, the source node will transmit the data to each target node and the target relay in the first time slot at the data transmission rate of the source node. Ready.

505. When receiving data sent by the source node in the first time slot, the target node stores the received data.

In this embodiment, when the target node receives the data sent by the source node in the first time slot, it does not directly decode the received data, but stores the received data, and in subsequent steps. After receiving the data transmitted by the relay device through the second time slot, the received data is combined and decoded.

506. When receiving data sent by the source node in the first time slot, the target relay device processes the data in the second time slot to obtain modulated data.

When the source node sends data to the relay device using the data transmission rate of the source node, not every relay device can successfully decode the received data. The relay device that can successfully decode only has a maximum data transmission rate greater than The target relay device of the data transmission rate of the source node. Based on the received data, the target relay device first decodes the received data to obtain decoded data, and then encodes the decoded data by using the original encoding method or a new encoding method to obtain modulated data. In addition, the target relay device can effectively eliminate the noise data in the data by processing the data in the second time slot.

It should be noted that, in the foregoing step 505, the process of storing the received data by the target node and the process of processing the received data by the target relay device in step 506 are performed simultaneously, and in this embodiment, only the storage from the target node is received. As step 505, the target relay device processes the received data as step 506. The above step 505 and the above step 506 do not represent a specific execution sequence.

507. The target relay device sends the modulated data to the target node in the second time slot.

After the modulated data is obtained, the target relay device will transmit the modulated signal to the target node in the second time slot using the data transmission rate of the source node.

508. The target node performs combined decoding on the data received in the first time slot and the modulated data received in the second time slot.

When receiving the modulated data transmitted by the target relay device in the second time slot, the target node will be at the first The data received in the time slot and the modulated data received in the second time slot are combined and decoded to obtain a diversity enhanced data.

In order to facilitate the understanding of the entire process of data transmission, a detailed explanation will be given below with a specific example.

6 is a schematic diagram of wireless multi-relay coordinated transmission for a wireless backhaul link, where the source node is a data source base station, the number of relay devices is N, and the channel gains of the source node and the N relay devices are respectively h _SR1 , h _SR2 , h _SR3 , . . . , h _SRN , the target node is an aggregate base station, the channel gain of the data source base station and the aggregate base station is h _sd , and the channel gains of the N relay devices and the aggregate base station are respectively h _R1d , h _R2d , h _R3d , . . . , h _RNd . Based on the channel information, the source node determines from the N relay devices that the target relay device is the first L relay devices. After the user equipment sends the user data to the data base station, the data source base station sends the user data to the aggregation base station and the L relay devices in the first time slot, and the L target relay devices receive the second time slot in the second time slot. The user data is decoded, and the decoded data is re-encoded, and then the re-encoded data is sent to the aggregation base station in the second time slot, and the aggregated base station receives the data and the second time slot in the first time slot. The received data is combined and decoded to obtain hierarchically enhanced data.

In order to more intuitively demonstrate the superiority of the data transmission method provided by the present invention, the present invention will also show the spectrum utilization curve obtained by using different data transmission methods. Referring to FIG. 7, curve 1 is a spectrum utilization curve obtained by using the data transmission method provided by the present invention, curve 2 adopts a spectrum utilization curve obtained by direct transmission, and curve 2 is a coordinated transmission method using all relay devices. The spectrum utilization curve is obtained, and curve 3 is the spectrum utilization curve obtained by the cooperative transmission method of the relay device. The number of relay devices in the simulation process is 10. It can be seen from FIG. 7 that the spectrum utilization rate is the highest when data transmission is performed by the method provided by the present invention.

According to the method provided by the embodiment of the present invention, the source node determines the maximum data receiving rate of each relay device according to the channel information, and determines the data transmission rate of the source node according to the maximum data receiving rate of each relay device, and further Determining the target relay device, and then transmitting data to the target node and the target relay device by using the data transmission rate of the source node in the first time slot, and the target relay device is in the second The data is processed in the time slot and the processed data is sent to the target node. Since the data transmission rate of the source node in the present invention is not simply determined by the channel gain of a certain relay device, the maximum data reception rate of the relay device determined by the channel information is determined, thereby ensuring a higher data transmission rate. Under the premise of large, as many relay devices as possible participate in the coordinated transmission process, so that the diversity gain and channel capacity are large, and the spectrum utilization rate is improved.

It should be noted that, when the data transmission device provided by the foregoing embodiment transmits data, only the division of the above functional modules is illustrated. In actual applications, the function distribution may be completed by different functional modules as needed. The internal structure of the data transmission device is divided into different functional modules to perform all or part of the functions described above. In addition, the data transmission method and the data transmission device embodiment provided by the foregoing embodiments are in the same concept, and the specific implementation process is described in detail in the method embodiment, and details are not described herein again.

A person skilled in the art may understand that all or part of the steps of implementing the above embodiments may be completed by hardware, or may be instructed by a program to execute related hardware, and the program may be stored in a computer readable storage medium. The storage medium mentioned may be a read only memory, a magnetic disk or an optical disk or the like.

The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalents, improvements, etc., which are within the spirit and scope of the present invention, should be included in the protection of the present invention. Within the scope.

Claims

A data transmission device, characterized in that the device comprises:

a receiving rate determining module, configured to determine a maximum data receiving rate of each relay device according to channel information, where the channel information includes a channel gain of the source node and the target node, and a channel gain of the source node and each relay device a channel gain of each relay device and the target node, a data transmission power of the source node, a data transmission power of the relay device, and a Gaussian white noise power of the relay device;

a transmission rate determining module, configured to determine a data transmission rate of the source node according to a maximum data receiving rate of each relay device;

a device determining module, configured to determine a target relay device according to a data transmission rate of the source node;

a sending module, configured to send data to the target node and the target relay device by using a data transmission rate of the source node in a first time slot, where the target relay device is in a second time slot The data is processed to obtain modulated data, and the modulated data is transmitted to the target node.
The device according to claim 1, wherein the device further comprises:

An obtaining module, configured to acquire a channel gain of the source node and each relay device;

a sorting module, configured to sort the channel gain of the source node and each relay device from large to small;

a numbering module, configured to number the relay devices corresponding to the channel gain from small to large according to the channel gain order result;

The receiving rate determining module is configured to determine a maximum data receiving rate of each relay device one by one according to the relay device number.
The apparatus according to claim 1, wherein the maximum data receiving rate of each of the relay devices determined by the receiving rate determining module is:

Wherein, V i is the maximum data receiving rate of the i-th relay device,
The data reception rate of the i-th relay device in the first time slot,
For the sum of the data transmission rates of the first to the ith relay devices in the second time slot, N is the number of relay devices, P is the data transmission power of the source node, and P' is the data of the relay device. Transmit power,
For the channel gain of the source node and the i-th relay device, |h Sd | 2 is the channel gain of the source node and the target node,
For the channel gain of the i-th relay device and the target node, N 0 is the Gaussian white noise power of the relay device.
The apparatus according to claim 3, wherein the data transmission rate of the source node determined by the transmission rate determining module is:

Where R is the data transmission rate of the source node.
The device according to claim 1, wherein the device determining module is configured to acquire a data receiving rate of each relay device in a first time slot; and data of each relay device in a first time slot The receiving rate is compared with the data transmission rate of the source node; the relay device whose data receiving rate in the first time slot is not less than the data transmission rate of the source node is used as the target relay device.
A data transmission method, characterized in that the method comprises:

Determining, according to channel information, a maximum data reception rate of each relay device, the channel information including a channel gain of the source node and the target node, a channel gain of the source node and each relay device, and each relay device Channel gain of the target node, data transmission power of the source node, and relay design The data transmission power and the Gaussian white noise power of the relay device;

Determining a data transmission rate of the source node according to a maximum data receiving rate of each relay device;

Determining a target relay device according to a data transmission rate of the source node;

Transmitting data to the target node and the target relay device by using a data transmission rate of the source node in a first time slot, and processing, by the target relay device, the data in a second time slot And obtaining modulated data, and transmitting the modulated data to the target node.
The method according to claim 6, wherein before determining the maximum data receiving rate of each relay device according to the channel information, the method further includes:

Obtaining a channel gain of the source node and each relay device;

Sorting the channel gain of the source node and each relay device from large to small;

According to the channel gain order result, the relay devices corresponding to the channel gain are numbered from small to large;

Determining, according to the channel information, a maximum data receiving rate of each relay device, including:

The maximum data reception rate of each relay device is determined one by one according to the relay device number.
The method according to claim 6, wherein the maximum data receiving rate of each relay device determined according to the channel information is:

Wherein, V i is the maximum data receiving rate of the i-th relay device,
The data reception rate of the i-th relay device in the first time slot,
For the sum of the data transmission rates of the first to the ith relay devices in the second time slot, N is the number of relay devices, P is the data transmission power of the source node, and P' is the data of the relay device. Transmit power,
For the channel gain of the source node and the i-th relay device, |h Sd | 2 is the channel gain of the source node and the target node,
The channel gain of the i-th relay device and the target node, and N 0 is the Gaussian white noise power of the relay device.
The method according to claim 8, wherein the determined data transmission rate of the source node according to a maximum data receiving rate of each relay device is:

Where R is the data transmission rate of the source node.
The method according to claim 6, wherein determining the target relay device according to the data transmission rate of the source node comprises:

Obtaining a data receiving rate of each relay device in the first time slot;

Comparing the data reception rate of each relay device in the first time slot with the data transmission rate of the source node;

A relay device having a data reception rate not less than a data transmission rate of the source node in the first time slot is used as a target relay device.