WO2016181861A1

WO2016181861A1 - Terminal device and base station device

Info

Publication number: WO2016181861A1
Application number: PCT/JP2016/063374
Authority: WO
Inventors: 淳悟後藤; 中村　理; 泰弘浜口
Original assignee: シャープ株式会社
Priority date: 2015-05-08
Filing date: 2016-04-28
Publication date: 2016-11-17
Also published as: JP2018107483A

Abstract

There has been a problem in that when the transmission modes of terminal devices that are multiplexed by a base station device by means of Superposition Coding (SC) are different, a data signal and reference signal are multiplexed, channel estimation accuracy deteriorates, and throughput is reduced. Provided is a base station device that transmits data to a plurality of terminal devices, said base station device having a signal multiplexing unit that multiplexes data signals of a first and second terminal device on the same resource, a transmission power control unit that configures the transmission power allocated to a data signal addressed to the second terminal device to be higher than the transmission power allocated to a data signal addressed to the first terminal device, and a control information generation unit that generates control information for reporting information relating to different downlink transmission modes to the first and second terminal devices which transmit data signals at different transmission powers. Control information including the transmission mode of the other terminal device is generated by the control information generation unit in the first and/or second terminal device.

Description

Terminal apparatus and base station apparatus

The present invention relates to a terminal device and a base station device.

In the mobile communication system, the system bandwidth has been widened due to the rapid increase in traffic. However, improvement of frequency utilization efficiency, which is a limited resource, is one of the issues. In communication systems such as LTE (Long Termination Evolution) and LTE-A (LTE-Advanced) of 3GPP (Third Generation Partnership Project), base station devices (base stations, transmitting stations, transmission points, downlink transmitters, uplinks) In communication between a receiving device, a transmitting antenna group, a transmitting antenna port group, eNodeB) and a plurality of terminal devices, interference between terminal devices is generally maintained by maintaining orthogonality between terminal devices (also referred to as inter-user interference). In recent years, standardization has been carried out on the premise of one frequency division multiple access (FDMA: “Frequency” Division “Multiple” Access) of an access method that prevents the occurrence of).

For example, 3GPP LTE Rel. 8, OFDM (Orthogonal Frequency Division Multiplexing) is used in the downlink (communication from the base station device to the terminal device), and DFT-S-OFDM (Discrete Fourier Transform) in the uplink (communication from the terminal device to the base station device). Spread (OFDM) has been specified.

In recent years, NOMA (Non-Orthogonal Multiple Multiplex) that allocates the same time, frequency, and spatial resources (same spatial precoding) to a plurality of terminal devices and transmits them in a non-orthogonal multiplexed manner in order to increase system capacity and communication opportunities. (Access) technology is being studied (see Non-Patent Document 1). Since signals transmitted from the base station apparatus to a plurality of terminal apparatuses are transmitted by non-orthogonal multiplexing by Superposition Coding (also referred to as SC or SCM: “Superposition” Coded ”Modulation), inter-user interference occurs. Therefore, the terminal device needs to cancel or suppress the interference between users. As a technique for canceling the interference between users, for example, CWIC (Codeword level interference cancellation) using an interference signal decoding result or SLIC (Symbol level interference interference canceling using a signal before decoding the interference signal is used. ) Further, maximum likelihood detection (MLD: Maximum Likelihood Detection) is also applicable as a NOMA signal detection method.

When the base station device multiplexes signals addressed to a plurality of terminal devices by SC, it is conceivable that the transmission mode (TM: “Transmission” Mode) of the multiplexed terminal devices is different. Here, the transmission mode includes a transmission mode in which a reference signal used for data demodulation is CRS (Cell-Specific Reference Signal). For example, transmission mode 1 for single antenna port, transmission mode 2 for transmission diversity, transmission mode 3 for large delay CDD (Cyclic Delay Diversity), transmission modes 4 and 6 for closed loop MIMO (Multiple Input Multiple Output), and for multi-user MIMO There is a transmission mode 5 or the like. As another transmission mode, there is a transmission mode using URS (UE-Specific Reference Signal) or DMRS (De-Modulation Reference Signal) for data demodulation. For example, there are a transmission mode 8 in which single-user MIMO and multi-user MIMO can be used, a transmission mode 9 in which 8-layer transmission is possible, and a transmission mode 10 in which downlink cooperative communication is possible.

However, when non-orthogonal multiplexing is performed on the data signal addressed to the terminal device in the transmission mode using CRS as the reference signal used for data demodulation and the data signal addressed to the terminal device in the transmission mode using URS as the reference signal used for data demodulation The data and the reference signal are multiplexed by the SC, so that the channel estimation accuracy is deteriorated and the throughput is lowered. In addition, when there are a plurality of data signals addressed to a terminal device in a transmission mode in which the reference signal used for data demodulation is URS, even when these data signals are non-orthogonal multiplexed by SC, the antenna port to be used is different. The data and the reference signal may be multiplexed by the SC, and there is a similar problem.

The present invention has been made in view of the above points. When there are terminal apparatuses set with different transmission modes, data signals destined for these terminal apparatuses are non-orthogonally multiplexed using SC. An object of the present invention is to provide a communication method capable of improving transmission characteristics.

(1) The present invention has been made to solve the above problems, and one aspect of the present invention is a base station apparatus that transmits data signals to a plurality of terminal apparatuses, the base station apparatus Is a signal multiplexing unit that multiplexes data signals of at least the first terminal device and the second terminal device into the same resource, and a transmission power allocated to the data signal addressed to the first terminal device. A transmission power control unit that increases the transmission power assigned to the data signal and the first terminal device that transmits a data signal having a different transmission power and the second terminal device are notified of information regarding transmission modes of different downlink transmissions. A control information generating unit that generates control information, and including at least one of the first terminal device or the second terminal device including the transmission mode of another terminal device Generating a broadcast in the control information generating unit.

(2) Further, according to an aspect of the present invention, in the information regarding the transmission mode included in the control information generated by the control information generation unit, at least a reference signal used for channel estimation of data demodulation is a user-specific reference signal. There are a first transmission mode and a second transmission mode in which a reference signal used for channel estimation of data demodulation is a cell-specific reference signal.

(3) In addition, according to one aspect of the present invention, the base station apparatus generates a transmission signal that multiplexes by generating user-specific reference signals of data signals addressed to the first terminal apparatus and the second terminal apparatus. And the transmission signal generator is at least one of a data signal multiplexing method and a user-specific reference signal multiplexing method according to a combination of the transmission modes of the first terminal device and the second terminal device. Is different.

(4) Further, according to one aspect of the present invention, the information regarding the transmission mode included in the control information generated by the control information generation unit includes at least one of the first terminal device and the second terminal device. It includes at least one of resource element information to which the number of antenna ports, antenna port number, number of layers, or user-specific reference signal to be used for transmission of user-specific reference signals of other terminal devices is assigned.

(5) In addition, according to an aspect of the present invention, when the second transmission mode is set in the first terminal device using control information generated by the control information generation unit, the second terminal According to the transmission mode of the apparatus, the data signal of the first terminal apparatus is allocated to the resource element of the user-specific reference signal transmitted in the first transmission mode, or no signal addressed to the first terminal apparatus is allocated. Switch between.

(6) In addition, according to an aspect of the present invention, when the second transmission mode is set in the first terminal device using the control information generated by the control information generation unit, the second terminal Depending on whether the device can receive information on the transmission mode of the first terminal device, the data signal of the second terminal device is allocated to the resource element of the user-specific reference signal transmitted in the first transmission mode, or Switch whether to assign any signal addressed to the terminal device 2.

(7) In addition, according to one aspect of the present invention, when the first transmission mode is set in the first terminal device using control information generated by the control information generation unit, the second terminal Whether to allocate the user-specific reference signal of the first terminal device or the data of the first terminal device to the resource element of the user-specific reference signal transmitted in the first transmission mode according to the transmission mode of the device Switch.

(8) Further, according to one aspect of the present invention, when the first transmission mode is set in the first terminal device using the control information generated by the control information generation unit, the second terminal Assigning the user-specific reference signal of the first terminal device to the resource element of the user-specific reference signal to be transmitted in the first transmission mode depending on whether the device can receive information on the transmission mode of the first terminal device; Whether to allocate data of the first terminal device is switched.

(9) Moreover, according to one aspect of the present invention, when the first transmission mode is set in the first terminal device using the control information generated by the control information generation unit, the second terminal Depending on the transmission mode of the apparatus, the data signal of the second terminal apparatus is allocated to the resource element of the user-specific reference signal transmitted in the first transmission mode, or no signal addressed to the second terminal apparatus is allocated. Switch between.

(10) One aspect of the present invention is a terminal device that receives a signal in which data signals of a plurality of terminal devices transmitted from a base station device are multiplexed. The terminal devices are assigned to the same resource. A signal detection unit for detecting a desired signal from a signal multiplexed with a different transmission power from a data signal addressed to another terminal device, a control information detection unit for detecting control information transmitted from the base station device, and the control information A reference signal separation unit for identifying a signal arranged in a resource element used for transmission of a user-specific reference signal from information on a downlink transmission mode and a transmission mode of another terminal device included in the reference signal separation The user element is a user-specific reference signal, data signal, or nothing is placed in the resource element used to transmit the user-specific reference signal. Or to determine which is the used transmission frame.

(11) Further, according to one aspect of the present invention, the transmission mode received by the control information detection unit and the transmission mode of the other terminal device are at least a reference signal used for estimating a propagation path for data demodulation. There are a first transmission mode of a signal and a second transmission mode in which a reference signal used for channel estimation of data demodulation is a cell-specific reference signal.

(12) Further, according to one aspect of the present invention, when the transmission power allocated to a desired signal is set lower than the transmission power allocated to a data signal addressed to another terminal apparatus, the reference signal separation unit is configured to A signal arranged in a resource element used for transmitting a user-specific reference signal is determined according to the transmission mode.

(13) In addition, according to one aspect of the present invention, when the transmission power allocated to a desired signal is set lower than the transmission power allocated to a data signal addressed to another terminal apparatus, the reference signal separation unit The signal arranged in the resource element used for transmitting the user-specific reference signal is determined depending on whether the information on the transmission mode can be received.

According to the present invention, transmission characteristics in NOMA can be improved.

It is a figure which shows an example of a structure of the system which concerns on this invention. It is a figure which shows an example of a structure of the base station apparatus which concerns on this invention. It is a figure which shows an example of a structure of the transmission signal generation part 101 which concerns on this invention. It is a figure which shows an example of a structure of the terminal device which concerns on this invention. It is a figure which shows an example of a structure of the signal separation part 204 which concerns on this invention. It is a figure which shows an example of a structure of the signal detection part 205 which concerns on this invention. It is a figure which shows an example of a structure of the desired signal detection part 2054 which concerns on this invention. It is a figure which shows an example of the flowchart of the transmission process which concerns on this invention. It is a figure which shows an example of the flowchart of the transmission process which concerns on this invention. It is a figure which shows an example of the flowchart of the transmission process which concerns on this invention. It is a figure which shows an example of a structure of the base station apparatus which concerns on this invention.

Hereinafter, embodiments will be described with reference to the drawings. In each of the following embodiments, the communication system includes a base station device (transmitting device, cell, transmission point, transmitting antenna group, transmitting antenna port group, component carrier, serving cell, eNodeB, Pico eNodeB, small cell, RRH: Radio Remote Head , LPN: Low Power Node) and a terminal device (terminal, mobile terminal, receiving point, receiving terminal, receiving device, receiving antenna group, receiving antenna port group, UE: User Equipment). In this specification, it is assumed that the downlink (communication from the base station apparatus to the terminal apparatus, hereinafter referred to as the downlink) is used, but the transmission method of the present invention is the uplink (from the terminal apparatus to the base station apparatus). (Hereinafter referred to as uplink), and may be applied to a case where a plurality of signals are multiplexed by SC in uplink transmission or multi-user MIMO is performed in uplink transmission. . Further, the present invention may be applied not only to transmission of control information between a base station apparatus and a terminal apparatus, but also to communication between a base station apparatus and a relay station apparatus, between a relay station apparatus and a terminal apparatus, or between terminals.

FIG. 1 shows an example of the configuration of a system according to the present invention. The system includes a base station apparatus 10 and terminal apparatuses 21 to 25. In addition, the number of terminal devices is not limited to this example, and the number of antennas of each device may be one or plural. In addition, the base station apparatus 10 may perform communication using a so-called licensed band obtained from the country or region where the wireless provider provides the service, or use permission from the country or region. Communication using a so-called unlicensed band that is not required may be performed. Further, the base station apparatus 10 may be a macro base station apparatus with a wide coverage, or a pico base station apparatus (Pico eNB: evolved Node B, SmallCell, Low Power Node, Remote Radio) having a narrower coverage than the macro base station device. (Also called Head)). In this specification, the frequency band other than the license band is not limited to the example of the unlicensed band, and may be a white band (white space) or the like. Further, the base station apparatus 10 may apply a CA (Carrier-Aggregation) technique that uses a plurality of component carriers (CC: also referred to as "Component Carrier" or Serving "cell") in a band used in LTE communication.

The base station apparatus 10 transmits a downlink data signal using PDSCH (Physical Downlink Shared CHANnel), and transmits control information including a transmission parameter used for the data signal by PDCCH (Physical Downlink Control CHANnel) or EPDCCH (Enhanced PDCCH). . The terminal devices 21 to 25 detect DCI (also referred to as Downlink Control Information, DL grant) of control information notified by PDCCH or EPDCCH by blind decoding, and down-convert based on transmission parameters included in DCI Link data signals are detected. In uplink transmission, the terminal devices 21 to 25 blindly transmit DCI (also referred to as UL grant when reporting transmission parameters of uplink transmission) transmitted from the base station device 10 by PDCCH or EPDCCH. Data transmission in uplink transmission is performed based on transmission parameters detected by decoding and included in DCI. Data transmission in uplink transmission is transmitted by PUSCH (Physical Uplink Shared CHannel), and control information of uplink transmission such as ACK / NACK (Acknowledgement / Negative Acknowledgement) and propagation path for SR (Scheduling Request) and downlink data Quality information (CSI: “Channel State Information”) is transmitted by PUCCH (Physical Uplink Control Control CHannel).

Here, the base station apparatus 10 determines a frequency resource used in downlink data transmission to each terminal apparatus by frequency scheduling. When the base station apparatus 10 selects data transmission by OFDM by frequency scheduling or uses a received power difference (path loss difference) between terminal apparatuses, Superposition Coding (also referred to as SC or SCM: Superposition Coded Modulation) In some cases, data transmission by NOMA (Non-Orthogonal Multiple Access) is selected. When non-orthogonal multiplexing is performed in the SC, the transmission power used for downlink data transmission is distributed to users multiplexed in the SC. Therefore, the transmission power is different from the OFDM transmission in which signals of a plurality of terminal devices are not multiplexed in a normal SC. . In addition, since the terminal device detects the interference between users caused by multiplexing in the SC by removing or suppressing it, the base station device needs to notify control information necessary for detecting the interference signal. For example, when the base station device multiplexes the

terminal devices

21 and 22 by SC, it is conceivable that the power allocated to the terminal device 21 with a small path loss is made smaller than the power allocated to the terminal device 22 with a large path loss. In this case, in the terminal device 21, a signal addressed to the terminal device 22 to which more power is allocated becomes an interference signal, and it is difficult to detect a desired signal unless the interference signal having a large power is suppressed or removed. Further, the base station apparatus performs pairing for determining a combination of terminal apparatuses that perform non-orthogonal multiplexing in frequency scheduling. In order to perform pairing so as to increase the system throughput, it is desirable that the number of terminal device candidates capable of non-orthogonal multiplexing is large. Therefore, a downlink transmission mode (TM: “Transmission” Mode) is set for each terminal device, but it is important that non-orthogonal multiplexing is possible even with a larger number of combinations of transmission modes. Here, the transmission mode includes a transmission mode (hereinafter referred to as CRS-based transmission mode) in which a reference signal used for data demodulation is CRS (Cell-Specific Reference Signal) and URS (UE-Specific). There is a transmission mode (hereinafter referred to as URS base transmission mode) in which Reference Signal, user-specific reference signal) or DMRS (De-Modulation Reference Signal) is used for data demodulation. In the following embodiments, a method for realizing good transmission characteristics even when data signals addressed to terminal devices in different transmission modes are multiplexed by the SC will be described.

(First embodiment)
FIG. 2 shows an example of the configuration of the base station apparatus according to the present invention. However, the minimum blocks necessary for the present invention are shown. In the figure, for simplicity of explanation, each base station apparatus has one transmission / reception antenna. However, actually, a plurality of transmission antennas may be provided, and the same processing may be performed by each transmission antenna. The base station apparatus receives a signal transmitted from the terminal apparatus via PUCCH or PUSCH by the reception antenna 105 and inputs the signal to the radio reception unit 106. The radio reception unit 106 down-converts the received signal to a baseband frequency, performs A / D (Analog / Digital) conversion, and removes a CP (Cyclic Prefix) from the digital signal, thereby controlling the control information detection unit 107. To enter. The control information detection unit 107 detects control information transmitted on the PUCCH from the received signal and control information such as PH (Power Headroom) transmitted on the PUSCH, and inputs the detected control information to the radio resource control unit 108. The radio resource control unit 108 determines allocation of frequency resources used for downlink data transmission based on CSI or the like as frequency scheduling. The frequency resource allocation will be described on the assumption that it is performed in units of RB (Resource Block) composed of 12 subcarriers in one subframe or in units of RBG (Resource Block Group) in which a plurality of RBs are grouped. The invention is not limited to this. Here, one subframe is composed of 2 slots, and one slot is composed of 7 OFDM symbols. However, the present invention is not limited to this example. The radio resource control unit 108 determines a combination and resource allocation (RA: Resource Allocation or Resource Assignment, hereinafter referred to as RA information) of a terminal device that performs OFDM transmission that is not multiplexed by SC and a terminal device that is multiplexed by SC in frequency scheduling. The radio resource control unit 108 determines transmission power to be allocated to each terminal device with respect to terminal devices multiplexed by SC. Further, the radio resource control unit 108 performs MCS (Modulation and Coding Scheme) or MIMO (Multiple Input Multiple Output) transmission of data addressed to each terminal device by adaptive modulation and coding (also referred to as link adaptation). In the case of application of MIMO and MIMO transmission, the number of streams (number of transmission layers) is determined. The radio resource control unit 108 inputs RA information, MCS, and information on the number of transmission streams to the control information generation unit 109.

The control information generation unit 109 generates the control information according to the DCI format determined by the downlink transmission mode of each terminal device and the setting of RRC (Radio Resource Control) for each terminal device. Here, as the DCI format, a plurality of formats are defined according to applications, DCI format 1 for downlink single antenna, DCI format 1A for transmission diversity, DCI format 1B, 2, 2B for SU-MIMO, DCI format 2A for 2C, Large Delay CDD (Cyclic Delay Diversity), DCI format 2C for MU-MIMO, DCI format 2D for downlink cooperative communication, etc. are defined, and DCI format for single antenna for uplink transmission 0, DCI format 4 for MIMO is defined. The control information generation unit 109 inputs the generated control information to the transmission signal generation unit 101 in order to generate downlink data and notify the terminal device. Here, the base station apparatus uses the DCI format used in the transmission mode of NOMA transmission for the terminal apparatus multiplexed on the SC, and detects control information necessary for removing or suppressing the interference signal and the signal multiplexed on the SC. The control information (additional information) necessary for is notified. However, the present invention may be applied to an existing transmission mode, or may be realized by setting to add information on an interference signal necessary for reception processing of NOMA transmission by RRC or the like.

The transmission signal generation unit 101 receives a data bit string to be transmitted to each terminal device. FIG. 3 shows an example of the configuration of the transmission signal generation unit 101 according to the present invention. As shown in the figure, the input data bit string is input to the error correction encoding units 1011-1 to 1011-2. Error correction coding sections 1011-1 to 1011-2 perform error correction code coding on the input data bit string. For example, a turbo code, an LDPC (Low Density Parity Check) code, a convolutional code, or the like is used as the error correction code. The types of error correction codes performed by error correction coding sections 1011-1 to 1011-2 may be determined in advance by the transmission / reception apparatus, may be notified as control information for each transmission / reception opportunity, or may be transmitted. Switching may be performed according to a parameter determined in advance according to the mode and a parameter notified by the control information. Further, the coding rate of error correction coding is input from the control information generation unit 109, and the error correction coding units 1011-1 to 1011-2 are coding rates used for downlink data transmission by puncturing (rate matching). To realize.

Modulation sections 1012-1 to 1012-2 receive modulation scheme information from control information generation section 109 and modulate the encoded bit string input from error correction encoding sections 1011-1 to 1011-2. Thus, a modulation symbol string is generated. Examples of the modulation scheme include QPSK (Quaternary Phase Shift Keying), 16 QAM (16-ary Quadrature Amplitude Modulation), 64 QAM, and 256 QAM. Modulation sections 1012-1 to 1012-2 output the generated modulation symbol sequence to transmission power control sections 1013-1 to 1013-2.

The transmission power control units 1013-1 to 1013-2 receive transmission power information assigned to terminal devices multiplexed by the SC from the control information generation unit 109, and perform transmission power control. The signal multiplexer 1014 receives and multiplexes the signals of the terminal device multiplexed by the SC. Here, as a method of multiplexing by SC, there are a method of modulating a signal addressed to each terminal device with a Gray code and adding it as it is, and a method of adding so that a signal point arrangement after multiplexing at SC becomes a Gray code. However, it may be determined in advance by the transmission / reception apparatus, may be notified as control information for each transmission / reception opportunity, or may be switched according to a parameter notified by the transmission mode or control information. Also, the signal multiplexing unit 1014, when the frequency resource to which the data signal addressed to the terminal device multiplexed by SC does not completely match, for example, when the data signal is multiplexed by SC with only some frequency resources, SC Only the signal of the frequency resource to be multiplexed is multiplexed. When data signals addressed to different combinations of terminal devices depending on frequency resources are multiplexed by SC, signal multiplexing section 1014 multiplexes signals by SC according to frequency resource allocation. The transmission signal allocation unit 1019 receives a transmission signal sequence from the signal multiplexing unit 1014, and further receives, from the transmission mode determination unit 1018, information on the transmission mode combination described later and the transmission mode combination of the terminal device on which the data signal is multiplexed in the SC. Is done. The transmission signal allocating unit 1019 converts the transmission signal sequence into RB indicated by RA information input from the control information generating unit 109, transmission mode combination described later, and transmission mode combination information of the terminal device in which the data signal is multiplexed in the SC. Assign accordingly.

On the other hand, the transmission mode determination unit 1018 holds information on the downlink transmission mode for each terminal device, and identifies the terminal device that transmits downlink data from the control information input from the control information generation unit 109. Further, the transmission mode determination unit 1018 includes a reference signal generation unit 1016 and a transmission signal allocation unit that transmit information on a transmission mode for each terminal device that transmits data and information on a combination of transmission modes of terminal devices on which data signals are multiplexed in the SC. 1010. The reference signal generation unit 1016 generates a reference signal according to the transmission mode of the allocated terminal apparatus in frequency resources using OFDM transmission (data transmission in which signals of a plurality of terminal apparatuses are not multiplexed by SC). Specifically, at least URS or DMRS is generated in frequency resources used for data transmission to a terminal device in a transmission mode using URS or DMRS for data demodulation, and URS or DMRS is not generated in other frequency resources. Other reference signals are generated. A method for generating a reference signal of frequency resources used for NOMA transmission by multiplexing signals of a plurality of terminal devices at the SC in the reference signal generation unit 1016 will be described later. The reference signal multiplexing unit 1015 receives the transmission signal sequence from the transmission signal allocation unit 1019, receives the reference signal sequence from the reference signal generation unit 1016, and multiplexes these signal sequences to generate a frame of the transmission signal. . Here, downlink reference signals include CRS (Cell-Specific Reference Signal), URS (UE-Specific Reference Signal) related to PDSCH, DMRS (De-Modulation Reference Signal) related to EPDCCH, NZP CSI-RS ( Non-Zero Power Channel State Information Reference Signal), ZP CSI-RS (Zero Power Channel State Information Reference Signal) and DRS (Discovery Reference Signal, Discovery Signal). Further, in this embodiment, the transmission power of the reference signal is the same in the case where the data signals addressed to a plurality of terminal devices are multiplexed by NOMA in the SC and the OFDM signal in which the data signals addressed to the plurality of terminal devices are not multiplexed in the SC. May be different or different. That is, when data signals addressed to a plurality of terminal devices are multiplexed by NOMA by SC, the transmission power of the data and the reference signal may be the same or different when the transmission power is distributed to these data signals. Here, at least when the transmission power of the data and the reference signal is different, the base station apparatus needs to notify the terminal apparatus of the transmission power as control information, or notify it in association with other control information. The control information multiplexing unit 1017 multiplexes the signal sequence input from the reference signal multiplexing unit 1015 and the control information such as DCI input from the control information generation unit 109 and inputs the multiplexed information to the IFFT unit 102.

The IFFT unit 102 receives a frame of a transmission signal in the frequency domain, and converts the frequency domain signal sequence into a time domain signal sequence by performing inverse fast Fourier transform for each OFDM symbol. The time domain signal sequence is input to the transmission processing unit 103. The transmission processing unit 103 inserts a CP into the signal sequence, converts it into an analog signal by D / A (Digital / Analog), and up-converts the converted signal to a radio frequency used for transmission. The transmission processing unit 103 amplifies the up-converted signal with PA (Power Amplifier), and transmits the amplified signal via the transmission antenna 104. As described above, the base station apparatus transmits a signal addressed to the terminal apparatus. Here, FIG. 11 shows an example of a configuration when the base station apparatus has a plurality of transmission antennas. This figure shows the case where the number of transmission antennas (the number of antenna ports) is P, and the same processing as in FIG. Further, the number of antenna ports used for data transmission by the base station apparatus is notified to the terminal apparatus. When the base station apparatus precodes a data signal transmitted using a plurality of antenna ports, the applied precoding is notified by PMI (PrecodingPreMatrix Indicator), or the data signal and the reference signal are similar. Send with precoding.

FIG. 4 shows an example of the configuration of the terminal device according to the present invention. However, the minimum blocks necessary for the present invention are shown. In order to simplify the explanation, the figure will be described assuming that each transmitting / receiving antenna of the terminal device is one. The terminal device receives a signal transmitted through the downlink by the receiving antenna 201 and inputs the signal to the reception processing unit 202. The reception processing unit 202 down-converts the received signal to the baseband frequency, performs A / D conversion, and removes the CP from the digital signal. Reception processing section 202 outputs the signal after CP removal to FFT section 203. The FFT unit 203 converts the input received signal sequence from a time domain signal sequence to a frequency domain signal sequence by fast Fourier transform, and outputs the frequency domain signal sequence to the signal separation unit 204.

FIG. 5 shows an example of the configuration of the signal separation unit 204 according to the present invention. In the figure, in the signal separation unit 204, the frequency domain signal sequence input from the FFT unit 203 is input to the reference signal separation unit 2041. The reference signal separation unit 2041 converts the signal input based on the downlink transmission mode stored in the transmission mode holding unit 2045 into the reference signal CRS, URS, DMRS, CSI-RS, DRS, and other signals. These are separated and output to the propagation path estimation unit 206 and the control information separation unit 2042, respectively. Details of the operation of the reference signal separation unit 2041 will be described later. Control information separation section 2042 separates the input signal into a control signal transmitted on PDCCH, EPDCCH, and PDSCH and a data signal transmitted on PDSCH, and outputs them to control information detection section 2044 and assigned signal extraction section 2043, respectively. . The control information detecting unit 2044 performs blind decoding on the DCI format determined by the transmission mode and RRC setting in CSS (Common SS) or USS (UE-specific SS) set in PDCCH or EPDCCH. Is detected. In addition, when control information is received by RRC signaling of higher-layer control information on PDSCH, control information detection section 2044 detects it by control information reception processing. The control information detection unit 2044 outputs, to the signal detection unit 205, transmission parameters (additional information) of signals addressed to other terminal devices that interfere with transmission parameters (RA information and MCS) of signals addressed to the own station. Here, the additional information is information on whether or not the data signal is multiplexed on the SC, and information on whether or not interference removal or suppression is necessary to detect the desired signal when the data signal is multiplexed on the SC. This is information related to the transmission mode of another terminal device that is multiplexed, transmission parameters necessary for detecting an interference signal addressed to another terminal device that is multiplexed by the SC, and the like. In addition, when receiving information on the downlink transmission mode of the own station, the control information detection unit 2044 inputs the information to the transmission mode holding unit 2045. On the other hand, allocation signal extraction section 2043 extracts a transmission signal based on RA information included in a transmission parameter of a signal addressed to the own station.

The propagation path estimation unit 206 uses different reference signals for data demodulation depending on the downlink transmission mode, and is a frequency estimated by reference that can be used for data demodulation among the reference signals multiplexed and transmitted with the data signal. The response is output to the signal detection unit 205. Here, when data signals addressed to a plurality of terminal devices are multiplexed by NOMA in the SC, the base station device distributes power to the data signals addressed to the plurality of terminal devices multiplexed by the SC. For this reason, the transmission power of NOMA transmission differs from that of OFDM transmission that is not multiplexed by SC, and the terminal device needs information (power ratio) of the transmission power of the reference signal and the data signal in the reception process. This power ratio information may be reported as control information and output from the control information detection unit 2044 to the propagation path estimation unit 206, or may be estimated from the received power of the reference signal without being notified as control information. good. Further, the propagation path estimation unit 206 inputs the frequency response estimated using the transmitted reference signal to the control information generation unit 207 for CSI transmission and data demodulation on the PUCCH. Control information generating section 207 transmits using PUCCH. Control information is generated using a format corresponding to the content to be transmitted at the transmission timing, such as SR, ACK / NACK, and CSI. The control information transmission unit 208 inserts a CP into the signal sequence, converts the signal into an analog signal by D / A, and up-converts the converted signal to a radio frequency used for transmission. Control information transmission section 208 amplifies the upconverted signal with PA, and transmits the amplified signal via transmission antenna 209.

FIG. 6 shows an example of the configuration of the signal detection unit 205 according to the present invention. In the signal detection unit 205, the transmission parameter of the signal addressed to another terminal device that interferes with the data signal sequence input from the signal separation unit 204 is input to the interference signal detection unit 2051, and the data signal sequence and the signal addressed to its own station Transmission parameters are input to the interference cancellation unit 2053. The interference signal detection unit 2051 detects an interference signal based on the estimated frequency response value corrected to the power ratio of the interference signal input from the propagation path estimation unit 206 and the transmission parameter input from the signal separation unit 204. Here, the detection of the interference signal may be performed using CWIC (Codeword interference 用いる Cancellation) using the result of error correction decoding or SLIC (Symbol level InterferencecellCancellation) using the demodulation result without performing error correction decoding. Further, the output of the interference signal detection unit 2051 may use a hard decision value or a soft value (LLR: Log Likelihood Ratio). The interference signal reproduction unit 2052 generates a replica of the interference signal from the estimated frequency response corrected to the detected bit sequence of the interference signal or the LLR sequence and the power ratio of the interference signal, and outputs it to the interference removal unit 2053. The interference signal detection unit 2051 and the interference signal reproduction unit 2052 do nothing in the case of OFDM transmission in which the desired signal and the interference signal are not multiplexed by the SC. The interference removal unit 2053 performs interference removal by subtracting the replica of the interference signal from the data signal sequence, and inputs the signal sequence after the interference removal and the transmission parameter of the signal addressed to the own station to the desired signal detection unit 2054.

FIG. 7 shows an example of the configuration of the desired signal detection unit 2054 according to the present invention. The desired signal detection unit 2054 has been corrected to the power ratio of the desired signal input from the propagation path estimation unit 206 and the transmission parameter of the signal sequence after interference cancellation input from the interference cancellation unit 2053 and the signal addressed to the own station. The estimated value of the frequency response is output to the propagation path compensator 2054-1. The propagation path compensator 2054-1 performs a process of compensating for the distortion of the wireless propagation path on the signal sequence after interference cancellation using the input frequency response estimation value. The propagation path compensation unit 2054-1 outputs the signal sequence after propagation path compensation to the demodulation unit 2054-2. Demodulation section 2054-2 receives information on the modulation method (modulation multi-level number, whether or not the signal after SP is added to become a Gray code, etc.) included in the transmission parameter of the signal addressed to the own station. The signal sequence after propagation path compensation is demodulated to obtain a bit-sequence LLR sequence. Decoding section 2054-3 receives the coding rate information included in the transmission parameter of the signal addressed to the own station, and performs decoding processing on the LLR sequence. Decoding section 2054-3 makes a hard decision on the decoded LLR sequence, determines the presence / absence of an error bit by cyclic redundancy check (CRC: Cyclic Redundancy Check), and outputs the information on the presence / absence of error bit to control information generation unit 207 If there is no error, a data bit string is output. In the present embodiment, the case where the desired signal detection unit 2054 uses a successive interference canceller (SIC: Successive InterferencecellCanceller) such as CWIC or SLIC has been described, but the present invention is not limited to this, and a parallel interference canceller ( PIC: “Parallel” Interference ”Canceller), maximum likelihood detection (MLD:“ Maximum ”Likelihood” Detection), or turbo equalization that performs iterative processing may be used.

FIG. 8 is a diagram showing an example of a flowchart of a transmission process according to the present invention. First, the base station apparatus generates control information for setting a downlink transmission mode for each terminal apparatus in advance and transmits the control information to the terminal apparatus from the transmission processing unit 103. The radio resource control unit 108 Determine the combination. The transmission mode discriminating unit 1018 confirms that a terminal device that requires detection of a desired signal after interference removal or suppression with a small transmission power allocation (hereinafter referred to as a terminal device that performs interference removal / suppression) is in the CRS-based transmission mode. Identify (S11). The transmission mode discriminating unit 1018 determines that a terminal device capable of detecting a desired signal without performing interference removal or suppression with a large transmission power allocation (hereinafter referred to as a terminal device without interference removal / suppression) is a URS-based transmission mode. Is determined (S12). When the transmission mode determination unit 1018 determines that the terminal device that does not cancel or suppress interference is the URS base transmission mode, the reference signal generation unit 1016 performs the terminal device that performs interference cancellation or suppression for the resource element of the URS of the terminal device that does not cancel or suppress interference. The reference signal multiplexing unit 1015 does not place the data of the terminal device that performs interference removal / suppression in the resource element of the URS of the terminal device that does not perform interference removal / suppression, and the reference signal multiplexing unit 1015 does not cancel the interference. A transmission frame is generated in which the reference signal of the terminal apparatus that removes and suppresses interference is not arranged in the resource element of the URS of the terminal apparatus that is not suppressed (S13).

Note that a CRS-based transmission mode terminal device that removes and suppresses interference when receiving data is an antenna that transmits information about whether or not to place data in a resource element of URS and a URS addressed to a terminal device that does not perform interference removal and suppression. Port information or the number of transmission layers (number of streams, number of ranks) is required. Here, the number and position of resource elements used for URS transmission differ between the number of layers up to 2 (antenna ports 7 and 8) and the number of layers of 3 or more (antenna ports 7, 8, 9,...). The control information generation unit 109, with respect to a terminal device that performs interference removal / suppression, information on the transmission mode of the terminal device that does not perform interference removal / suppression, the number of layers, the number of antenna ports to be used The information regarding the resource element of URS, such as, is transmitted as additional information of control information. The reference signal generation unit 1016 generates a reference signal in the URS resource element of the terminal apparatus that does not cancel or suppress interference, and the reference signal multiplexing unit 1015 generates a transmission frame by arranging the reference signal in the URS resource element ( S14). On the other hand, when the terminal device that does not cancel or suppress interference is set to the CRS base transmission mode, the transmission mode determination unit 1018 does not use the URS for any of the terminal devices multiplexed by the SC. Both the terminal device that suppresses and the terminal device that does not cancel or suppress interference do not generate URS, and the reference signal multiplexing unit 1015 generates data by arranging data in the resource element of URS, and proceeds to S15 (S16). ). The signal multiplexing 1014 multiplexes signals addressed to a plurality of terminal devices by SC (S15).

As described above, a transmission frame is generated when the transmission modes of a plurality of terminal apparatuses that transmit data signals multiplexed by SC are different. Therefore, the terminal apparatus that cancels / suppresses interference transmits the downlink transmission mode of the local station stored in the transmission mode holding unit 2045 and the additional information included in the control information detected by the control information detection unit 2044 by blind decoding. Information on whether or not the data signal is multiplexed on the SC, and information on whether or not interference cancellation or suppression is necessary to detect the desired signal if multiplexed on the SC, other information multiplexed on the SC Information related to the transmission mode of the terminal device is input to the reference signal separation unit 2041. When the CRS base transmission mode is set, the reference signal separation unit 2041 determines which transmission process of FIG. 8 is used by the base station apparatus based on such information, and arranges data in the resource element of the URS Identify whether or not Therefore, when the reference signal separation unit 2041 identifies that neither data nor reference signals are arranged in the URS resource element, the signal received by the URS resource element is transmitted to both the propagation path estimation unit 206 and the control information separation unit 2042. Discard without outputting.

On the other hand, a terminal device that does not cancel or suppress interference may use only the information on the downlink transmission mode of its own station for identifying a reference signal used for data demodulation, and information on whether or not it is multiplexed in SC and transmission of interference signals. It is not necessary to receive parameters.

In this embodiment, when data signals addressed to a plurality of terminal devices are multiplexed by SC, the transmission mode of the terminal device that performs interference removal / suppression is the CRS base transmission mode, and the terminal device that does not perform interference removal / suppression is the CRS base transmission mode. The example in which the multiplexing method of the data signal and the reference signal of the terminal apparatus for canceling / suppressing the interference is changed depending on the transmission mode or the URS base transmission mode has been described. Note that the multiplexing method of the data signal and the reference signal of the terminal apparatus that performs interference cancellation / suppression may be changed depending on control information transmitted to the terminal apparatus that does not perform interference cancellation / suppression. For example, when the base station device does not notify the terminal device that does not cancel / suppress interference, the terminal device that performs interference removal / suppression does not notify the CRS base transmission mode or cannot receive this information (for NOMA) The transmission mode is not the same as this mode, or the NOMA is not set in RRC, or the NOMA transmission mode or NOMA cannot be set. If the terminal device is notified of information indicating that it is in a mode, or if this information is receivable (NOMA transmission mode or NOMA is set in RRC, etc.), transmission of a terminal device that does not eliminate or suppress interference Regardless of the mode, data may be arranged in the resource element of URS. In this case, it means that the transmission mode of the terminal apparatus that does not cancel or suppress interference is temporarily switched to the CRS base transmission mode. Therefore, in such a case, no URS is transmitted to a terminal device that does not cancel or suppress interference.

As described above, in this embodiment, data and reference signals are not multiplexed in SC due to different transmission modes of terminal devices when multiplexed in SC, and deterioration of the channel estimation system can be suppressed. Further, throughput can be improved by NOMA multiplexing in different transmission modes.

(Second Embodiment)
In the previous embodiment, when data signals addressed to a plurality of terminal apparatuses are multiplexed by SC, an example in which the transmission mode of the terminal apparatus that performs interference cancellation / suppression is the CRS-based transmission mode has been described. An example in which the transmission mode of the terminal device to be suppressed is the URS base transmission mode will be described. First, the example of a structure of the base station apparatus in this embodiment is the same as that of previous embodiment, and is FIG. Moreover, the example of a structure of the terminal device in this embodiment is the same as that of previous embodiment, and is FIG. Therefore, in the present embodiment, only different processing will be described, and description of similar processing will be omitted.

FIG. 9 is a diagram showing an example of a flowchart of transmission processing according to the present invention. First, the base station apparatus generates control information for setting a downlink transmission mode for each terminal apparatus in advance and transmits the control information to the terminal apparatus from the transmission processing unit 103. The radio resource control unit 108 Determine the combination. The transmission mode discriminating unit 1018 identifies that the terminal device that performs interference removal / suppression with a small transmission power allocation is in the URS base transmission mode (S21). The transmission mode discriminating unit 1018 determines whether or not a terminal apparatus that does not perform interference removal / suppression with a large transmission power allocation is set to the CRS base transmission mode (S22). When the transmission mode determination unit 1018 determines that the terminal device that does not perform interference cancellation / suppression is the CRS base transmission mode, the reference signal generation unit 1016 does not generate the reference signal of the URS resource element of the terminal device that performs interference cancellation / suppression, and The transmission signal allocating unit 1019 generates a transmission frame in which the data of the terminal device that performs interference removal / suppression is arranged in the resource element of the URS of the terminal device that performs interference removal / suppression (S23).

Note that a terminal device in the URS base transmission mode that removes and suppresses interference at the time of data reception has information on the arrangement of reference signals or data in resource elements of URS (information related to the transmission mode of the terminal device that does not remove or suppress interference). is necessary. For this reason, the control information generation unit 109 uses the information on whether the transmission mode of the terminal apparatus that does not remove or suppress interference is CRS-based transmission mode or URS-based transmission mode as additional information of control information for the terminal apparatus that performs interference removal or suppression. Send. The reference signal generation unit 1016 does not generate a reference signal for a terminal device that does not cancel or suppress interference for URS resource elements, and the transmission signal allocation unit 1019 arranges data for a terminal device that does not cancel or suppress interference in the URS resource elements Then, a transmission frame is generated (S24). On the other hand, when the terminal device that does not cancel / suppress interference is set to the URS base transmission mode, the transmission mode determination unit 1018 uses the URS for all of the terminal devices multiplexed by the SC. A terminal device that suppresses and a terminal device that does not cancel or suppress interference generate a URS that can be used for data demodulation, and the reference signal multiplexing unit 1015 generates a transmission frame by arranging one reference signal in the resource element of the URS Then, the process proceeds to S25 (S26). Therefore, a plurality of URS signals destined for a plurality of terminal devices on which data signals are multiplexed by the SC are not generated and multiplexed by the SC. However, the present invention is not limited to this example, and a plurality of URS signals destined for a plurality of terminal devices to which data signals are multiplexed in SC by OCC (Orthogonal Cover Code) of length X are generated, and multiplexing by codes is performed. You can do it. The signal multiplexing 1014 multiplexes signals addressed to a plurality of terminal devices by SC (S25).

As described above, a transmission frame is generated when the transmission modes of a plurality of terminal apparatuses that transmit data signals multiplexed by SC are different. Therefore, the terminal apparatus that cancels / suppresses interference transmits the downlink transmission mode of the local station stored in the transmission mode holding unit 2045 and the additional information included in the control information detected by the control information detection unit 2044 by blind decoding. Information on whether or not the data signal is multiplexed on the SC, and information on whether or not interference cancellation or suppression is necessary to detect the desired signal if multiplexed on the SC, other information multiplexed on the SC Information related to the transmission mode of the terminal device is input to the reference signal separation unit 2041. When the URS base transmission mode is set, the reference signal separation unit 2041 determines which transmission processing of the base station apparatus uses in FIG. 9 based on these information, and transmits the reference signal to the resource element of the URS. Identify which data is located. Therefore, when the reference signal separation unit 2041 identifies that the data is not allocated to the resource element of the URS, the signal received by the resource element of the URS is output to the control information separation unit 2042 for data demodulation. CRS is used to estimate the frequency response to be used. When the base station apparatus precodes the data signal, the control information detection unit 2044 performs PMI (Precoding の Matrix Indicator) of the desired signal, PMI of the transmission parameter of the interference signal, or the desired signal and the interference signal. Control information notified as PMI or the like used in common for both may be detected.

In the present embodiment, when the URS base transmission mode is set for both the terminal device that performs interference cancellation / suppression and the terminal device that does not perform interference cancellation / suppression, the reference signal is arranged in the resource element of URS. It is conceivable that the number of transmission antenna ports (number of transmission layers) used for data transmission is different between the terminal apparatus that removes and suppresses interference and the terminal apparatus that does not remove and suppress interference. For example, when the number of transmission layers of a data signal addressed to a terminal device that performs interference cancellation / suppression is 3 or more and the number of transmission layers of a data signal addressed to a terminal device that does not perform interference cancellation / suppression is 2 or less, the terminal that performs interference cancellation / suppression The resource element of URS is different between the terminal device that does not cancel / suppress interference with the device. Therefore, the terminal device that performs interference cancellation / suppression receives the number of transmission layers of the terminal device that does not perform interference cancellation / suppression as control information, and only the URS resource elements of the terminal devices that do not perform interference cancellation / suppression are arranged with reference signals. -You may arrange | position data to the resource element which does not arrange | position URS of the terminal device which is not suppressed. That is, the resource element in which the terminal device that performs interference cancellation / suppression arranges the URS is a resource element that arranges the URS for the number of transmission layers of the terminal device that does not perform interference removal / suppression. Also, as another example, the terminal device that performs interference removal / suppression and the terminal device that does not perform interference removal / suppression may be configured to match the settings of the terminal device with a small number of resource elements used for URS transmission. The number of transmission layers of the interference signal is notified as control information to the terminal device to be suppressed and the terminal device to which interference is not removed / suppressed.

(Third embodiment)
In the previous embodiment, when data signals addressed to a plurality of terminal devices are multiplexed by SC, the transmission mode of the terminal device that performs interference removal / suppression is the URS base transmission mode, and only by the transmission mode of the terminal device that does not perform interference removal / suppression. Although the example in which the base station device changes the generation of the transmission frame has been described, in the present embodiment, an example in which the base station device changes the transmission frame according to the transmission mode of the terminal device that does not eliminate or suppress interference and control information that can be notified is described. To do. First, the example of a structure of the base station apparatus in this embodiment is the same as that of previous embodiment, and is FIG. Moreover, the example of a structure of the terminal device in this embodiment is the same as that of previous embodiment, and is FIG. Therefore, in the present embodiment, only different processing will be described, and description of similar processing will be omitted.

FIG. 10 is a diagram showing an example of a flowchart of the transmission process according to the present invention. First, the base station apparatus generates control information for setting a downlink transmission mode for each terminal apparatus in advance and transmits the control information to the terminal apparatus from the transmission processing unit 103. The radio resource control unit 108 Determine the combination. The transmission mode discriminating unit 1018 identifies that the terminal apparatus that performs interference removal / suppression with a small transmission power allocation is the URS base transmission mode (S31). The transmission mode determination unit 1018 identifies that a terminal device that does not perform interference cancellation / suppression with a large amount of power allocation can receive information related to the transmission mode of the terminal device that performs interference cancellation / suppression (S32). Further, when a terminal device that does not perform interference cancellation / suppression cannot receive information related to the transmission mode of the terminal device that performs interference cancellation / suppression, the description is omitted because it is the same as in the second embodiment. Here, being able to receive information related to the transmission mode of the terminal device that eliminates and suppresses interference means that it is a transmission mode for NOMA, or that NOMA is set in RRC. The fact that information related to the transmission mode of the terminal device to be removed / suppressed cannot be received is not a transmission mode for NOMA, NOMA is not set in RRC, or a transmission mode for NOMA or NOMA cannot be set And so on. The reference signal generation unit 1016 generates a reference signal of the URS resource element of the terminal apparatus that performs interference cancellation / suppression, and the reference signal multiplexing unit 1015 generates a transmission frame in which the reference signal is arranged in the URS resource element (S33). .

The transmission mode determination unit 1018 determines whether a terminal device that does not remove or suppress transmission interference is set to the CRS base transmission mode (S34). When the transmission mode determination unit 1018 determines that the terminal device that does not perform interference cancellation / suppression is the CRS-based transmission mode, the reference signal generation unit 1016 does not perform interference cancellation / suppression for the resource element of the URS of the terminal device that performs interference cancellation / suppression. The reference signal of the device is not generated, the transmission signal allocating unit 1019 does not place the data of the terminal device that does not perform interference cancellation / suppression in the resource element of the URS of the terminal device that performs interference cancellation / suppression, and the reference signal multiplexing unit 1015 Generate a transmission frame in which no reference signal of a terminal device that does not cancel or suppress interference is placed in the resource element of the URS of the terminal device to be suppressed (S35). In addition, the terminal device in the CRS base transmission mode that does not cancel or suppress interference when receiving data is information regarding whether to place data in the resource element of URS (information related to the transmission mode of the terminal device that performs interference cancellation or suppression). is required. For this reason, the control information generation unit 109, for a terminal device that does not cancel or suppress interference, information on the transmission mode of the terminal device that performs interference cancellation or suppression, the number of layers, the number of layers to be used, and the antenna to be used Information on the resource element of URS such as the port number is transmitted as additional information of the control information. On the other hand, when the terminal device that does not cancel / suppress interference is set to the URS base transmission mode, the transmission mode determination unit 1018 uses the URS for all of the terminal devices multiplexed by the SC. A terminal device that suppresses and a terminal device that does not cancel or suppress interference generate a URS that can be used for data demodulation, and the reference signal multiplexing unit 1015 generates a transmission frame by arranging one reference signal in the resource element of the URS Then, the process proceeds to S36 (S37). Therefore, a plurality of URS signals destined for a plurality of terminal devices on which data signals are multiplexed by the SC are not generated and multiplexed by the SC. However, the present invention is not limited to this example, and a plurality of URS signals destined for a plurality of terminal devices to which data signals are multiplexed by the SC by OCC of length X may be generated, and multiplexing by codes may be performed. The signal multiplexing 1014 multiplexes signals addressed to a plurality of terminal devices by SC (S36).

As described above, a transmission frame is generated when the transmission modes of a plurality of terminal apparatuses that transmit data signals multiplexed by SC are different. Therefore, the terminal apparatus that does not cancel or suppress the interference transmits the downlink transmission mode of the own station stored in the transmission mode holding unit 2045 and the additional information included in the control information detected by the control information detecting unit 2044 by blind decoding. Information on whether or not the data signal is multiplexed on the SC, and information on whether or not interference cancellation or suppression is necessary to detect the desired signal if multiplexed on the SC, other information multiplexed on the SC Information related to the transmission mode of the terminal device is input to the reference signal separation unit 2041. When the URS base transmission mode is set, the reference signal separation unit 2041 determines which transmission process of the base station apparatus uses in FIG. 10 based on such information, and also refers to the data in the URS resource element Identify that no signal is placed. Therefore, when the reference signal separation unit 2041 identifies that neither data nor reference signals are arranged in the URS resource element, the signal received by the URS resource element is transmitted to both the propagation path estimation unit 206 and the control information separation unit 2042. Discard without outputting. Therefore, the terminal apparatus uses CRS for estimating the frequency response used for data demodulation. When the base station apparatus precodes the data signal, the control information detection unit 2044 performs PMI (Precoding の Matrix Indicator) of the desired signal, PMI of the transmission parameter of the interference signal, or the desired signal and the interference signal. Control information notified as PMI or the like used in common for both may be detected.

On the other hand, a terminal device that eliminates and suppresses interference includes a downlink transmission mode of its own station for identification of a reference signal used for data demodulation, and a terminal device that does not cancel and suppress interference detected by the control information detection unit 2044 The information related to whether or not the information related to can be received.

The program that operates in the base station apparatus and terminal apparatus related to the present invention is a program that controls the CPU or the like (a program that causes a computer to function) so as to realize the functions of the above-described embodiments related to the present invention. Information handled by these devices is temporarily stored in the RAM at the time of processing, then stored in various ROMs and HDDs, read out by the CPU, and corrected and written as necessary. As a recording medium for storing the program, a semiconductor medium (for example, ROM, nonvolatile memory card, etc.), an optical recording medium (for example, DVD, MO, MD, CD, BD, etc.), a magnetic recording medium (for example, magnetic tape, Any of a flexible disk etc. may be sufficient. In addition, by executing the loaded program, not only the functions of the above-described embodiment are realized, but also based on the instructions of the program, the processing is performed in cooperation with the operating system or other application programs. The functions of the invention may be realized.

In addition, when distributing to the market, the program can be stored in a portable recording medium for distribution, or transferred to a server computer connected via a network such as the Internet. In this case, the storage device of the server computer is also included in the present invention. Further, part or all of the base station apparatus and terminal apparatus in the above-described embodiment may be realized as an LSI that is typically an integrated circuit. Each functional block of the base station apparatus and the terminal apparatus may be individually chipped, or a part or all of them may be integrated into a chip. Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. When each functional block is integrated, an integrated circuit controller for controlling them is added.

Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. In addition, when an integrated circuit technology that replaces LSI appears due to progress in semiconductor technology, an integrated circuit based on the technology can also be used.

Further, the present invention is not limited to the above-described embodiment. The terminal device of the present invention is not limited to application to a mobile station device, but is a stationary or non-movable electronic device installed indoors or outdoors, such as AV equipment, kitchen equipment, cleaning / washing equipment Needless to say, it can be applied to air conditioning equipment, office equipment, vending machines, and other daily life equipment.

As described above, the embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design changes and the like without departing from the gist of the present invention. The present invention can be modified in various ways within the scope of the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments are also included in the technical scope of the present invention. It is. Moreover, it is the element described in each said embodiment, and the structure which substituted the element which has the same effect is also contained.

This international application claims priority based on Japanese Patent Application No. 2015-095542 filed on May 8, 2015, and the entire contents of Japanese Patent Application No. 2015-095542 are hereby incorporated by reference. Included in international applications.

DESCRIPTION OF SYMBOLS 10 ... Base station apparatus 21-25 ... Terminal device 101 ... Transmission signal generation part 102 ... IFFT part 103 ... Transmission processing part 104 ... Transmission antenna 105 ... Reception antenna 106 ... Radio reception part 107 ... Control information detection part 108 ... Radio | wireless resource control Reference numeral 109 ... Control information generator 1011-1 to 1011-2 ... Error correction encoder 1012-1 to 1012-2 ... Modulator 1013-1 to 1013-2 ... Transmission power controller 1014 ... Signal multiplexer 1015 Signal multiplexing unit 1016 ... Reference signal generation unit 1017 ... Control signal multiplexing unit 1018 ... Transmission mode determination unit 1019 ... Transmission signal allocation unit 201 ... Reception antenna 202 ... Reception processing unit 203 ... FFT unit 204 ... Signal separation unit 205 ... Signal detection unit 206 ... Propagation path estimation unit 207 ... Control information generation unit 208 ... Control information transmission unit 209 ... Transmission Signal antenna 2041... Reference signal separation unit 2042... Control information separation unit 2043... Assignment signal extraction unit 2044... Control information detection unit 2045... Transmission mode holding unit 2051 ... Interference signal detection unit 2052. ... Desired signal detector 2054-1 ... Propagation path compensator 2054-2 ... Demodulator 2054-3 ... Decoder

Claims

A base station device that transmits data signals to a plurality of terminal devices,
The base station apparatus uses the signal multiplexing unit that multiplexes at least the data signals of the first terminal apparatus and the second terminal apparatus on the same resource, and the transmission power assigned to the data signal addressed to the first terminal apparatus. A transmission power control unit that increases transmission power assigned to a data signal addressed to a terminal device, and a transmission mode of downlink transmission different from each other to the first terminal device and the second terminal device that transmit data signals having different transmission power A control information generation unit for generating control information for notifying information,
A base station apparatus, wherein the control information generation unit generates control information including the transmission mode of another terminal apparatus in at least one of the first terminal apparatus or the second terminal apparatus.
The information related to the transmission mode included in the control information generated by the control information generation unit includes at least a reference signal used for channel estimation of data demodulation and a first transmission mode of a user-specific reference signal and propagation of data demodulation. The base station apparatus according to claim 1, wherein the reference signal used for path estimation has a second transmission mode of a cell-specific reference signal.
The base station apparatus includes a transmission signal generation unit that generates and multiplexes user-specific reference signals of data signals addressed to the first terminal apparatus and the second terminal apparatus,
The transmission signal generating unit is characterized in that at least one of a data signal multiplexing method and a user-specific reference signal multiplexing method differs according to a combination of the transmission modes of the first terminal device and the second terminal device. The base station apparatus according to claim 2.
Information related to the transmission mode included in the control information generated by the control information generation unit includes transmission of a user-specific reference signal of another terminal device to at least one of the first terminal device or the second terminal device. The base station apparatus according to claim 3, wherein at least one of resource element information to which the number of antenna ports to be used, the antenna port number, the number of layers, or a user-specific reference signal is allocated is included.
When the second transmission mode is set in the first terminal device using the control information generated by the control information generation unit,
According to the transmission mode of the second terminal apparatus, a data signal of the first terminal apparatus is allocated to a resource element of a user-specific reference signal transmitted in the first transmission mode, or a signal addressed to the first terminal apparatus The base station apparatus according to claim 3, wherein switching is performed to assign nothing.
When the second transmission mode is set in the first terminal device using the control information generated by the control information generation unit,
Depending on whether the second terminal apparatus can receive information on the transmission mode of the first terminal apparatus, the data signal of the second terminal apparatus is transmitted to the resource element of the user-specific reference signal transmitted in the first transmission mode. The base station apparatus according to claim 3, wherein the base station apparatus switches between assigning and not assigning any signal addressed to the second terminal apparatus.
When the first transmission mode is set in the first terminal device using the control information generated by the control information generation unit,
According to the transmission mode of the second terminal apparatus, the user specific reference signal of the first terminal apparatus is assigned to the resource element of the user specific reference signal transmitted in the first transmission mode, or the first terminal apparatus 4. The base station apparatus according to claim 3, wherein whether to allocate data is switched.
When the first transmission mode is set in the first terminal device using the control information generated by the control information generation unit,
Depending on whether the second terminal apparatus can receive information on the transmission mode of the first terminal apparatus, the resource element of the user-specific reference signal transmitted in the first transmission mode is used as the user-specific reference of the first terminal apparatus. The base station apparatus according to claim 3, wherein the base station apparatus switches between assigning a signal and assigning data of the first terminal apparatus.
When the first transmission mode is set in the first terminal device using the control information generated by the control information generation unit,
According to the transmission mode of the second terminal apparatus, a data signal of the second terminal apparatus is allocated to a resource element of a user-specific reference signal transmitted in the first transmission mode, or a signal addressed to the second terminal apparatus The base station apparatus according to claim 3, wherein switching is performed to assign nothing.
A terminal device that receives a signal in which data signals of a plurality of terminal devices transmitted from a base station device are multiplexed,
The terminal device includes a signal detection unit that detects a desired signal from signals multiplexed with different transmission power from data signals addressed to other terminal devices allocated to the same resource, and control information transmitted from the base station device. A reference signal for identifying a signal to be arranged in a resource element used for transmission of a user-specific reference signal from information on a control information detection unit to be detected and a downlink transmission mode and a transmission mode of another terminal device included in the control information A separation part,
The reference signal separation unit is characterized by determining which transmission frame of a user-specific reference signal, a data signal, or nothing is used for a resource element used for transmission of a user-specific reference signal. Terminal device to do.
The transmission mode received by the control information detector and the transmission mode of the other terminal device are at least a first transmission mode of a user-specific reference signal as a reference signal used for channel estimation of data demodulation and a data demodulation mode. The terminal apparatus according to claim 10, wherein the reference signal used for propagation path estimation has a second transmission mode of a cell-specific reference signal.
When the transmission power allocated to a desired signal is set lower than the transmission power allocated to a data signal addressed to another terminal device,
12. The terminal apparatus according to claim 11, wherein the reference signal separation unit determines a signal arranged in a resource element used for transmitting a user-specific reference signal according to the transmission mode of the other terminal apparatus.
When the transmission power allocated to a desired signal is set lower than the transmission power allocated to a data signal addressed to another terminal device,
The reference signal separation unit determines a signal arranged in a resource element used for transmitting a user-specific reference signal according to whether the other terminal device can receive information on the transmission mode. Terminal device.