JP2018101818A - Terminal and base station device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem in which, when a base station device notifies terminals multiplexed by Superposition Coding(SC) of all information of an interference signal for each communication opportunity, overhead increases as the amount of control information increases.SOLUTION: A base station device for transmitting data signal to multiple terminals has a signal multiplex unit for multiplexing the data signal of at least first and second terminals by SC, a control information generation unit for generating control information including additional information related to data signal addressed to the second terminal for the first terminal, and a transmission processing unit for transmitting the signal multiplexed by the SC. The transmission processing unit transmits a signal obtained by performing SC of the data signal of the second terminal generated based on the transmission parameters associated with the additional information included in the control information generated in the control information generation unit, and the data signal of the first terminal.SELECTED DRAWING: Figure 2

Description

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

  In a mobile communication system, the system band has been widened due to a rapid increase in traffic. However, improvement of frequency utilization efficiency, which is a limited resource, is one of the problems. In communication systems such as LTE (Long Term Evolution) and LTE-A (LTE-Advanced) of 3GPP (Third Generation Partnership Project), base station devices (base stations, transmission stations, transmission points, downlink transmission devices, 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) 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 apparatus to the terminal apparatus), and DFT-S-OFDM (Discrete Fourier Transform) in the uplink (communication from the terminal apparatus to the base station apparatus). Spread OFDM) has been specified.

  In recent years, in order to increase system capacity and improve communication opportunities, NOMA (Non-Orthogonal Multiple Multiplex) that allocates the same time, frequency, and space resources (same space precoding) to a plurality of terminal devices and performs non-orthogonal multiplexing transmission (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 using 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 interference between users, for example, CWIC (Codeword level Interference Cancellation) for canceling interference using a decoding result of an interference signal, or SLIC (Symbol level Interference Cancellation) for canceling interference using a signal before decoding of the interference signal is used. ) Further, maximum likelihood detection (MLD) is also applicable as a NOMA signal detection method.

Media Tek Ink, “New SI Proposal: Study on Downlink Multiuser Superposition Transmission for LTE,” RP-150496, 3GPP, March 2015

  When NOMA is realized by SC, a non-orthogonal multiplexed terminal apparatus detects an interference signal in the process of CWIC or SLIC reception processing, and therefore requires MCS information of the interference signal. Further, when the terminal device uses CWIC, the base station device performs error correction decoding of the interference signal, so that the base station device assigns information on frequency resources (resource allocation information, Resource Allocation Information and Resource Assignment Information) are required. Furthermore, when changing the ratio (power ratio) of transmission power distribution by combination (pairing) of non-orthogonal multiplexed terminal apparatuses, the base station apparatus also needs to notify the terminal apparatus of the power ratio. However, if the base station device notifies all non-orthogonal-multiplexed terminal devices of all these pieces of information as downlink control information for each communication opportunity, there is a problem that overhead increases as the amount of control information increases. .

  The present invention has been made in view of the above points, and provides a communication method capable of suppressing an increase in the amount of control information in NOMA.

  (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 Includes at least a signal multiplexing unit that multiplexes data signals of the first terminal device and the second terminal device by superposition coding, and an addition related to the data signal addressed to the second terminal device to the first terminal device A control information generating unit that generates control information including information, and a transmission processing unit that transmits a signal multiplexed by the superposition coding. The transmission processing unit is included in the control information generated by the control information generating unit. The data signal of the second terminal device and the data signal of the first terminal device generated based on the transmission parameter associated with the additional information The superposition coding signal is transmitted.

  (2) Further, according to one aspect of the present invention, the base station apparatus includes a transmission power control unit that controls transmission power of a data signal transmitted to the plurality of terminal apparatuses multiplexed by superposition coding, and the additional information Is a control value of transmission power assigned to the first terminal device or the second terminal device used in the transmission power control unit, and a transmission parameter associated with the additional information is a data signal addressed to the second The number of modulation levels and the coding rate applied to.

  (3) Further, according to one aspect of the present invention, the modulation multi-value number and the coding rate applied to the data signal addressed to the second which is a transmission parameter associated with the additional information are a plurality of candidates.

  (4) Further, according to an aspect of the present invention, the base station apparatus includes a transmission power control unit that controls transmission power of data signals transmitted to the plurality of terminal apparatuses multiplexed by superposition coding, and the additional information Is the number of modulation levels and the coding rate applied to the data signal addressed to the second terminal device, and the transmission parameter associated with the additional information is the first terminal used in the transmission power control unit This is a control value of transmission power assigned to the device or the second terminal device.

  (5) Further, according to an aspect of the present invention, the base station apparatus includes a transmission power control unit that controls transmission power of data signals transmitted to the plurality of terminal apparatuses multiplexed by superposition coding, and the additional information Is an adjustment value of a threshold value used when selecting a modulation multi-value number and a coding rate applied to a data signal addressed to the first terminal apparatus, and a transmission parameter associated with the additional information is the transmission power control The transmission power control value used in the transmission unit, the number of modulation multi-values applied to the data signal addressed to the second terminal apparatus, and the coding rate.

  (6) Further, according to one aspect of the present invention, the base station apparatus generates a reference signal and a transmission power control unit that controls transmission power of a data signal to be transmitted to the plurality of terminal apparatuses multiplexed by superposition coding. A reference signal generation unit that performs transmission power control of a reference signal according to a transmission power control value of the second terminal device used in the transmission power control unit, and associates the additional information with the additional information. The transmitted parameters are the number of modulation levels and the coding rate applied to the data signal addressed to the second terminal device.

  (7) Moreover, 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 device is addressed to another terminal device. A signal detection unit for detecting a desired signal from a signal multiplexed with a data signal and superposition coding, a control information detection unit for detecting control information transmitted from the base station device, and the other terminal device included in the control information An interference signal information identifying unit for identifying a transmission parameter used for the data signal addressed to the other terminal device from information related to the data signal addressed to the data signal, and the signal detection unit is a data signal addressed to the other terminal device An interference signal is detected using the transmission parameters used in the above, and a desired signal is detected by removing the detected interference signal.

  (8) Further, according to one aspect of the present invention, the information related to the data signal addressed to the other terminal device detected by the control information detection unit is a modulation multi-value applied to the data signal of the other terminal device. The transmission parameter used for the data signal addressed to the other terminal device, which is the number and the coding rate and is identified by the interference signal information identification unit, is the transmission power of the data signal addressed to the other terminal device.

  (9) Further, according to one aspect of the present invention, the information related to the data signal addressed to the other terminal device detected by the control information detection unit is a threshold value used when selecting the modulation multi-level number and the coding rate. The transmission parameter used for the data signal addressed to the other terminal device, which is an adjustment value and is identified by the interference signal information identification unit, includes the transmission power, the modulation multi-level number, and the encoding of the data signal addressed to the other terminal device. Rate.

  (10) Further, according to one aspect of the present invention, the information related to the data signal addressed to the other terminal device detected by the control information detection unit is transmission power of the data signal addressed to the other terminal device, The transmission parameters used for the data signal addressed to the other terminal device identified by the interference signal information identification unit are the number of modulation levels and the coding rate of the data signal addressed to the other terminal device.

  According to the present invention, an increase in the amount of control information in NOMA can be suppressed.

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 reception process which concerns on this invention. It is a figure which shows an example of the flowchart of the reception process 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 the flowchart of the reception process which concerns on this invention. It is a figure which shows an example of the table of MCS 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 terminal devices (terminal, mobile terminal, receiving point, receiving terminal, receiving device, receiving antenna group, receiving antenna port group, UE: User Equipment). Further, although the present specification assumes a downlink (communication from a base station apparatus to a terminal apparatus, hereinafter referred to as a downlink), the method for suppressing an increase in control information according to the present invention is defined as an uplink (terminal apparatus). To control information related to data transmission of communication from the base station apparatus to the base station apparatus (hereinafter referred to as uplink). In addition to transmission of control information between the base station device and the terminal device, the present invention includes control information between the base station device and the relay station device, control information between the relay station device and the terminal device, and control information for communication between terminals. May be applied. Further, the present invention describes an example in which the base station apparatus multiplexes and transmits data signals addressed to a plurality of terminal apparatuses in the SC. However, the present invention is not limited to this example, and it is possible to eliminate inter-cell interference and single user. You may apply to the control information of MIMO or multiuser MIMO.

  FIG. 1 shows an example of the configuration of a system according to the present invention. The system includes a base station device 10 and terminal devices 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. Moreover, 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, Small Cell, Low Power Node, Remote Radio, which has a narrower coverage than the macro base station apparatus. (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. The base station apparatus 10 may apply a CA (Carrier Aggregation) technique that uses a plurality of component carriers (also referred to as CC: 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 transmission parameters used for the data signal using PDCCH (Physical Downlink Control CHannel) or EPDCCH (Enhanced PDCCH). . Also, the terminal devices 21 to 25 detect blind control information DCI (also referred to as Downlink Control Information, DL grant) of control information notified by PDCCH or EPDCCH, and download it based on transmission parameters included in DCI. The link data signal is detected. Further, in the uplink, the terminal devices 21 to 25 perform blind decoding on DCI (also referred to as UL grant when the uplink transmission parameter is notified) transmitted from the base station device 10 by PDCCH or EPDCCH. And uplink data transmission based on transmission parameters included in DCI. Uplink data transmission is transmitted using PUSCH (Physical Uplink Shared CHannel), and uplink control information such as ACK / NACK (Acknowledgement / Negative Acknowledgement) and propagation path quality information for SR (Scheduling Request) and downlink data. (CSI: Channel State Information) is transmitted by PUCCH (Physical Uplink Control CHannel).

  Here, the base station apparatus 10 determines a frequency resource used for downlink data transmission to each terminal apparatus by frequency scheduling. The base station apparatus 10 selects superposition coding (also referred to as SC or SCM: Superposition Coded Modulation) when selecting data transmission by OFDM by frequency scheduling or using a received power difference (path loss difference) between terminal apparatuses. In some cases, NOMA (Non-Orthogonal Multiple Access) data transmission 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. However, in the conventional system, the terminal device does not detect a signal addressed to another terminal device. Therefore, in order to realize NOMA transmission, the base station apparatus needs to notify the terminal apparatus that suppresses or removes the interference signal of control information for detecting a signal addressed to another terminal apparatus that causes interference. There is. Therefore, in the following embodiment, a method for realizing NOMA transmission without significantly increasing the amount of control information 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 order to simplify the explanation, the figure will be described assuming that one transmitting / receiving antenna of the base station apparatus is provided. 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 is 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 uses 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 control information corresponding to the DCI format determined by the settings of the downlink transmission mode (TM: Transmission Mode) and RRC (Radio Resource Control) of each terminal from the input control information. Here, as the DCI format, a plurality of formats are defined according to applications, DCI format 1 for downlink single antenna, 1A, DCI format 2C for MU-MIMO, etc. are defined, and for uplink single antenna DCI format 0 and MIMO DCI format 4 are 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 to the terminal apparatus multiplexed by SC, and notifies control information (additional information) necessary for removing or suppressing the interference signal. 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. The error correction encoding units 1011-1 to 1011-2 perform error correction encoding 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 the error correction encoding units 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. Also, the coding rate of error correction coding is input from the control information generation unit 109, and the error correction coding units 10111-1 to 1011-2 are coding rates used for downlink data transmission by puncturing (rate matching). Is realized.

  Modulation sections 1012-1 to 1012-2 are supplied with modulation scheme information from control information generation section 109, and modulate the coded bit string input from error correction coding sections 1011-1 to 1011-2. Thus, a modulation symbol string is generated. Examples of the modulation scheme include QPSK (Quaternary Phase Shift Keying), 16QAM (16-ary Quadrature Amplitude Modulation), 64QAM, and 256QAM. Modulation sections 1012-1 to 1012-2 output the generated modulation symbol sequence to transmission power control sections 1013-1 to 1013-3.

  Transmission power control sections 1013-1 to 1013-2 receive transmission power information assigned to terminal devices multiplexed by SC from control information generation section 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. The transmission signal allocation unit 1018 receives the transmission signal sequence from the signal multiplexing unit 1014 and allocates the transmission signal sequence to the RB indicated by the RA information input from the control information generation unit 109.

  The reference signal multiplexing unit 1015 receives a transmission signal sequence from the transmission signal allocation unit 1018, receives a 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) are included. In the present embodiment, an example will be described in which the transmission power of the reference signal is the same in the case where a plurality of terminal apparatuses are multiplexed by NOMA in SC and the OFDM transmission in which the signals of the plurality of terminal apparatuses are not multiplexed in SC. That is, when data signals addressed to a plurality of terminal devices are multiplexed by NOMA by SC, the transmission powers of data and reference signals are different when transmission power is distributed to these data signals. The control information multiplexer 1017 multiplexes the signal sequence input from the reference signal multiplexer 1015 and the DCI control information input from the control information generator 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 performs inverse fast Fourier transform on each OFDM symbol unit to convert the frequency domain signal sequence into a time domain signal sequence. 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 upconverted signal with a 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.

  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 separates the input signal into CRS, URS, DMRS, CSI-RS, DRS, and other signals of the reference signal and outputs them to the propagation path estimation unit 206 and the control information separation unit 2042, respectively. . 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 detection 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 the 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 transmission parameters (RA information and MCS) of signals addressed to itself to the signal detection unit 205, and transmits transmission parameters of signals addressed to other terminal devices that cause interference to an interference signal information identification unit 2045. Output to. The interference signal information identification unit 2045 identifies transmission parameters of signals destined for other terminal devices that cause interference that is not notified as control information. Details will be described later. The interference signal information identification unit 2045 identifies the transmission parameter associated with the notified transmission parameter, and inputs the transmission parameter to the signal detection unit 205. 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 receives the reference signal multiplexed and transmitted with the data signal, and outputs the frequency response estimated for demodulation to the signal detection unit 205. Here, in this embodiment, since the transmission power of the reference signal is the same in the case of multiplexing a plurality of terminal devices in SC with NOMA and in the case of OFDM transmission in which the signals of the plurality of terminal devices are not multiplexed in SC. In the reception process, information on the power ratio between the reference signal and the data signal is required. This power ratio information is notified as control information and output from the control information detection unit 2044 to the propagation path estimation unit 206, or is not notified as control information, and is identified by the interference signal information identification unit 2045 to be propagation path estimation. Assume that the data is output to the unit 206. Details will be described later. Moreover, the propagation path estimation part 206 inputs the estimated frequency response into the control information generation part 207 in order to transmit CSI by 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 use CWIC (Codeword Level Interference Cancellation) using the result of error correction decoding or SLIC (Symbol Level Interference Cancellation) using the demodulation result without performing error correction decoding. In addition, 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 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 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 train after propagation path compensation to the demodulation unit 2054-2. Demodulation section 2054-2 receives information on the modulation method (modulation multi-value 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. The decoding unit 2054-3 receives the coding rate information included in the transmission parameter of the signal addressed to the own station, and performs a decoding process on the LLR sequence. Decoding section 2054-3 performs a hard decision on the decoded LLR sequence, determines the presence / absence of an error bit by cyclic redundancy check (CRC), and outputs information on the presence / absence of error bit to control information generation section 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) such as CWIC or SLIC has been described. However, the present invention is not limited to this, and a parallel interference canceller ( For example, PIC (Parallel Interference Canceller), Maximum Likelihood Detection (MLD), or turbo equalization that performs iterative processing may be used.

FIG. 8 is a diagram showing an example of a flowchart of the reception process according to the present invention. First, the control information detection unit 2044 detects MCS information included in transmission parameters of signals addressed to other terminal devices that interfere with MCS information included in transmission parameters of signals addressed to the own station (S10). Interference signal information identification unit 2045, the MCS index of own station signals and _{I MCS1,} the MCS index of the interference signal _{I MCS2} is input, a _E S / _{N 0} of the target corresponding to the MCS index _{f SN (I MCS1),} to obtain f _SN a _{(I MCS2),} respectively. Here, it is assumed that the conversion between the MCS index and the target E _S / N ₀ is realized by a method such as tabulated in advance. The interference signal information identifying unit 2045 of the terminal device to which the transmission power P ₁ (0 ≦ P ₁ ≦ 1) is assigned uses the desired signal transmission power P ₁ and the interference signal transmission power P ₂ (0 ≦ P ₂ ≦ 1). Need to identify. First, a case where the transmission power of the interference signal is higher than the desired signal (P ₁ <P ₂ ) and the MCS of the interference signal is lower than the desired signal will be described. In this case, it is assumed that the terminal device to which the transmission power P ₁ is assigned can completely cancel the interference, and if the other terminal device that causes interference does not cancel the interference, the MCS of the desired signal is set by the following equation.

…式（１）

... Formula (1)

…式（２）

... Formula (2)

However, N ₁ is the noise power in the terminal device to which the transmission power P ₁ is allocated, N ₂ is the noise power in the terminal device to which the transmission power P ₂ is allocated, and α ₁ and α ₂ are allocated to the transmission power P ₁ and P _2, respectively. This is an adjustment value (margin) of a threshold value at the time of MCS selection in consideration of the influence of channel estimation error and EVM (Error Vector Magnitude) in adaptive modulation coding in a terminal apparatus. α ₁ and α ₂ are determined in advance, or are notified (transmitted) to the terminal device to which transmission power P ₁ is assigned and the terminal device to which transmission power P ₂ is assigned. The notification method of α ₁ and α ₂ may be notified to the terminal device in advance by RRC or the like, may be notified to the terminal device at the same time as the MCS index by DCI, or a common value (α ₁ = α ₂ ) may be notified by RRC or DCI. Further, when the number of terminal apparatuses multiplexed by SC is 2, the transmission power P _{TOTAL for} downlink transmission is as follows.

…式（３）

... Formula (3)

However, it is assumed that the terminal apparatus to which transmission power P ₁ is assigned needs to eliminate interference, and the terminal apparatus to which transmission power P ₂ is assigned does not have to remove interference, with P ₁ <P ₂ being assigned. Interference signal information identification unit 2045 of the terminal device is allocated transmit power P ₁ is, alpha ₁ is the transmission power P ₁ of the desired signal from the equation (3) and equation (1) if it is known or notified P ₁ = (F _SN (I _MCS1 ) + α ₁ ) N ₁ , P ₂ = P _TOTAL − (f _SN (I _MCS1 ) + α ₁ ) N ₁ is identified (S11). In addition, in the interference signal information identifying unit 2045 of the terminal device to which the transmission power P ₂ is assigned, α ₂ is known or notified, and the transmission power P ₁ of the interference signal is set to P ₁ from Expression (2) and Expression (3). = {P _TOTAL -N ₂ (f _SN (I _MCS2 ) + α ₂ )} / {f _SN (I _MCS2 ) + α ₂ +1}, and the transmission power P _{2 of the} desired signal is obtained using Equation (3). Can also be identified.

The interference signal detection unit 2051 of the terminal apparatus to which the transmission power P ₁ is assigned detects the interference signal using the transmission power P ₂ of the interference signal that has identified the MCS index of the notified interference signal as I _MCS2, and then the interference signal The detection reproduction unit 2052 generates a replica of the interference signal (S12). The interference signal removal unit 2053 performs interference removal by subtracting a replica of the interference signal from the data signal sequence (S13). Desired signal detector 2054 detects the desired signal by using the transmission power P ₁ was identified as the transmission parameters provided (S14). Further, the terminal device to which the transmission power P ₂ is assigned detects the desired signal using the identification result of the transmission power P ₂ in the desired signal detection unit 2054 when interference cancellation is not performed. As described above, the terminal apparatus detects the desired signal multiplexed by the SC.

In the present embodiment, the case where constant transmission power is applied in the allocation RB notified by one control information has been described. However, the present invention may not be constant transmission power in all allocation RBs, and may be determined in advance. The transmitted RBG unit, a plurality of RBs, or a plurality of RBGs may be used as subbands, and transmission power may be identified in units of subbands as in the present embodiment. In this case, the MCS of the interference signal is notified in subband units, and is identified by P ₁ = {P _TOTAL -N ₂ (f _SN (I _MCS2 ) + α ₂ )} / {f _SN (I _MCS2 ) + α ₂ +1}. May be. Furthermore, it may be multiplexed by different terminal apparatuses and SCs in units of RBGs or subbands.

In the present embodiment, an example has been described in which P ₁ and P ₂ that are transmission powers of signals multiplexed in the SC are identified, and the identified transmission power values are used as they are in the reception process. However, the transmission used by the base station apparatus When the combination of power P ₁ and P ₂ is limited, for example, if the discrete value is P ₁ = {0.1, 0.2, 0.3, 0.4}, the base station apparatus sets possible nearest value of P ₁ of the transmission power may be identified to have been used. Further, in the above example, rounding off the first decimal place of the identified values of P ₁ and truncating may identify the transmission power by the base station apparatus is used in such rounding up. Further, when a discrete value is calculated from the identified transmission power value, the discrete value may be identified from the P ₂ value of the identified large transmission power.

In the present embodiment, an example in which the MCS of the interference signal is notified has been described. However, when SLIC or MLD is used for reception processing, only the modulation multi-level number may be notified, and the transmission power P _{1 of the} desired signal is assigned. The terminal device to be used may identify the transmission power by P ₁ = (f _SN (I _MCS1 ) + α ₁ ) N ₁ .

In addition, α ₁ and α ₂ may be 0, and in this case, the base station device does not need to notify the terminal device of α ₁ or α _2.

  As described above, in this embodiment, it is not necessary to notify the transmission power used at the time of multiplexing in the SC, and the overhead of control information can be reduced.

(Modification of the first embodiment)
In the previous embodiment, the case where the number of terminal apparatuses multiplexed by SC is two has been described, but in this modification, an example where the number U of terminal apparatuses multiplexed by SC is three or more will be described. First, the configuration example of the base station apparatus in this modification is the same as that of the previous embodiment, and is shown in FIG. However, the error correction coding units 1011-1 to 1011-2 of the transmission signal generation unit 101 of FIG. 3 have transmission power control units 1013-1 to 1013-1 as many as the number of terminal devices multiplexed by SC, Multiplexed by the multiplexing unit 1014. Further, the configuration example of the terminal device in the present modification is the same as that of the previous embodiment, and is shown in FIGS. Also, the flowchart of the reception process is the same as that of the previous embodiment, and is shown in FIG. Therefore, in the present embodiment, only different processing will be described, and description of similar processing will be omitted.

When the number of terminal devices multiplexed in SC is U, the transmission power P _{TOTAL for} downlink transmission is as follows.

…式（４）

... Formula (4)

Here, it is assumed that P ₁ ≦ P ₂ ≦... ≦ P _U , and the terminal apparatus removes an interference signal having a transmission power larger than that of a signal addressed to the own station by reception processing. Terminal device P ₁ is assigned is set MCS formula (2), the terminal _{device P i} is assigned, MCS is set by the following equation.

…式（５）

... Formula (5)

The terminal device to which P ₁ is assigned identifies P ₁ = (f _SN (I _MCS1 ) + α ₁ ) N ₁ from Equation (2). Next, the terminal device to which P ₁ is assigned identifies P ₂ = {f _SN (I _MCS1 ) + α ₂ } {(f _SN (I _MCS1 ) + α ₁ ) N ₁ + N ₂ } from Equation (5). If α _j (1 ≦ j ≦ U) and MCS of other terminal devices that cause interference are notified, P _U can be identified. However, if it is common to all terminal apparatuses multiplexed in SC, that is, α _j = α _i (1 ≦ i, j ≦ U and i ≠ j), the amount of control information can be minimized. Further, the approximation is made that the noise power N _j of other terminal devices is equivalent to the noise power N _i of the local station.

  In the present embodiment, the case where constant transmission power is applied in the allocation RB notified by one control information has been described. However, the present invention may not be constant transmission power in all allocation RBs, and may be determined in advance. The transmission power may be identified as in this embodiment in units of RBGs or subbands, and may be multiplexed by different terminal apparatuses and SCs in units of RBGs or subbands.

In the present embodiment, an example has been described in which P _i (1 ≦ i ≦ U), which is transmission power of a signal multiplexed in SC, is identified and the identified transmission power value is used as it is for reception processing. If there is a limitation on the combinations of transmission powers P _i used by the base station apparatus, for example, if P _i = discrete values such as {0.1, 0.2, 0.3, 0.4}, It may be identified that a value closest to the identified _Pi value among the settable transmission powers is used. Further, in the above example, decimal rounding and truncating the second largest value of transmission power identification P _i, rounded up the base station apparatus may identify the transmission power used and the like. Further, when a discrete value is calculated from the identified transmission power value, the discrete value may be identified from the identified large transmission power value.

In addition, α _i may be 0, and in this case, the base station device does not need to notify the terminal device of α _i.

  As described above, in this embodiment, it is not necessary to notify the transmission power used at the time of multiplexing in the SC, and the overhead of control information can be reduced.

(Second Embodiment)
In the previous embodiment, the example in which the MCS information of the interference signal is notified has been described. In the present embodiment, an example in which the transmission power of the desired signal is notified will be described. First, the configuration example of the base station apparatus in this modification is the same as that of the previous embodiment, and is shown in FIGS. Further, the configuration example of the terminal device in the present modification is the same as that of the previous embodiment, and is shown in FIGS. 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 the reception process according to the present invention. Control information detection section 2044 of the terminal device is allocated transmit power P ₁ detects the transmission power P ₁ and MCS information included in the transmission parameters of its own station of the signal (S20). However, information of the transmission power by the base station apparatus is notified may be transmission power P ₂ allocated to another terminal apparatus comprising an interference signal. Here, the number of terminal devices to be multiplexed by the SC and 2, the MCS index of own station signals and _{I MCS1,} the MCS index of the interference signal and _{I MCS2,} the target corresponding to the MCS index _E S / N _0, respectively _f SN _{(I MCS1),} and f _{SN (I MCS2).} The interference signal information identifying unit 2045 of the terminal device to which P ₁ is assigned needs to identify the MCS of the interference signal. First, the following equation is obtained from equations (1) to (3).

…式（６）

... Formula (6)

Here, the terminal apparatus to which P ₁ is assigned may be notified of α ₂ used for determining the MCS of the interference signal in advance by RRC or the like, or may be determined in advance, or DCI at the same time as the MCS of the desired signal. May be notified by RRC or DCI as a common value (α ₁ = α ₂ ) for all terminal apparatuses. The terminal device to which P ₁ is assigned _obtains a table of MCS and target E _S / N ₀ preset by the transceiver from the f _SN (I _MCS2 ) of the target E _S / N ₀ of the identified interference signal. The interference signal is converted into MCS by using it (S21). In addition, the terminal device to which P ₁ is assigned identifies the interference signal transmission power P ₂ from Equation (3) (S21). Subsequent processing is the same as that in the first embodiment, and thus description thereof is omitted.

  In the present embodiment, the case where constant transmission power is applied in the allocation RB notified by one control information has been described. However, the present invention may not be constant transmission power in all allocation RBs, and may be determined in advance. The transmission power may be notified in units of RBGs or subbands, in which case the MCS is identified in units of RBGs or subbands. Furthermore, it may be multiplexed by different terminal apparatuses and SCs in units of RBGs or subbands.

  In the present embodiment, a case has been described in which the base station apparatus notifies the transmission power to be allocated to the terminal apparatus and identifies the MCS of the interference signal. However, the terminal apparatus using SLIC or MLD for the reception processing does not require coding rate information. Therefore, only the modulation multi-level number (Modulation Order) may be identified.

In addition, α ₁ and α ₂ may be 0, and in this case, the base station device does not need to notify the terminal device of α ₁ or α _2.

  As described above, in this embodiment, it is not necessary to notify the transmission power used at the time of multiplexing in the SC, and the overhead of control information can be reduced.

(Modification of the second embodiment)
In the second embodiment, the case where the number of terminal apparatuses multiplexed by SC is 2 has been described, but in this modification, an example in which the number U of terminal apparatuses multiplexed by SC is 3 or more will be described. First, the configuration example of the base station apparatus in this modification is the same as that of the second embodiment, and is shown in FIG. However, the error correction coding units 1011-1 to 1011-2 of the transmission signal generation unit 101 of FIG. 3 have transmission power control units 1013-1 to 1013-1 as many as the number of terminal devices multiplexed by SC, Multiplexed by the multiplexing unit 1014. Further, the configuration example of the terminal device in the present modification is the same as that of the second embodiment, and is shown in FIGS. Also, the flowchart of the reception process is the same as that of the second embodiment and is shown in FIG. However, the terminal device multiplexed by SC is different from the second embodiment in that information of transmission power assigned to each multiplexed terminal device is notified. In the present embodiment, only different processing will be described, and description of similar processing will be omitted.

When the number of terminal devices multiplexed in SC is U, the transmission power P _{TOTAL for} downlink transmission is expressed by equation (4), P ₁ ≦ P ₂ ≦... ≦ P _U , and the terminal device is based on a signal addressed to the own station. Also, it is assumed that an interference signal having a large transmission power is removed by reception processing. Terminal device P ₁ is assigned is set MCS formula (1), the terminal _{device P i} is assigned, MCS is set in equation (5).

When the terminal device to which P ₁ is assigned is notified of α _{j of the} terminal device to which the interference signal P _j (2 ≦ j ≦ U) is assigned, it can identify the MCS according to Expression (5). However, if it is common to all terminal apparatuses multiplexed in SC, that is, α _j = α _i (1 ≦ i, j ≦ U and i ≠ j), the amount of control information can be minimized. Further, the approximation is made that the noise power N _j of other terminal devices is equivalent to the noise power N _i of the local station.

  In the present embodiment, the case where constant transmission power is applied in the allocation RB notified by one control information has been described. However, the present invention may not be constant transmission power in all allocation RBs, and may be determined in advance. The transmission power may be notified in units of RBGs or subbands, in which case the MCS is identified in units of RBGs or subbands. Furthermore, it may be multiplexed by different terminal apparatuses and SCs in units of RBGs or subbands.

  In the present embodiment, a case has been described in which the base station apparatus notifies the terminal apparatus of the transmission power assigned to each terminal apparatus multiplexed by SC and identifies the MCS of the interference signal. However, the terminal uses SLIC or MLD for reception processing. Since the apparatus does not need coding rate information, only the modulation multi-level number (Modulation Order) may be identified.

In addition, α _i may be 0, and in this case, the base station device does not need to notify the terminal device of α _i.

  As described above, in this embodiment, it is not necessary to notify the transmission power used at the time of multiplexing in the SC, and the overhead of control information can be reduced.

(Third embodiment)
In the previous embodiment, the example in which the transmission power of each terminal device multiplexed by the SC is notified and the MCS of the interference signal is identified has been described. However, in this embodiment, the transmission power of each terminal device multiplexed by the SC is identified. An example in which the MCS of the interference signal is identified based on the identified transmission power allocation value 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. However, since the processing of the reference signal generation unit 1016 and the reference signal multiplexing unit 1015 is different, it will be described later. Moreover, the example of a structure of the terminal device in this embodiment is the same as that of previous embodiment, and is FIG. However, in the present embodiment, the configuration example of the signal separation unit 204 of the terminal device is not FIG. 5 but FIG. In the present embodiment, only different processing will be described, and description of similar processing will be omitted.

  First, reference signal generation section 1016 generates a reference signal with the same power allocation as the transmission power of data for each terminal device multiplexed by SC. Next, the reference signal multiplexing unit 1015 multiplexes the reference signal for each terminal device to be multiplexed. As a reference signal multiplexing method, a different antenna port number may be assigned to each terminal device to be multiplexed, and multiplexing may be performed using an OCC (Orthogonal Cover Code) of length X, or may be multiplexed on different frequency resources (resource elements). May be. Since the transmission processing of other base station apparatuses is the same as that of the second embodiment, description thereof is omitted.

FIG. 11 is a diagram showing an example of a flowchart of reception processing according to the present invention. In the terminal device, the reference signal separated by the reference signal separation 2041 is input to the propagation path estimation unit 206 and the reference signal power measurement unit 3041. When the reference signal power measurement unit 3041 receives the NOMA-multiplexed data of the other terminal device in the SC, the reference signal power measurement unit 3041 estimates the transmission power allocated to the desired signal and the interference signal from the transmission power of the reference signal (S30). Specifically, when the number of terminal devices multiplexed by SC is U, the reference signal for each terminal device multiplexed by SC from a reference signal multiplexed by OCC or assigned to a different resource element , And averaged received power P _{AVG —} i (1 ≦ i ≦ U) is identified. The reference signal power measurement unit 3041 estimates P _i (1 ≦ i ≦ U) of the transmission power (power ratio) of each terminal apparatus multiplexed in SC by the following equation.

…式（７）

... Formula (7)

Here, if there is a limitation on the combination of transmission powers P _i used by the base station apparatus, for example, P _i = a discrete value such as {0.1, 0.2, 0.3, 0.4}. if, a value closest to the value of the transmission power identification of P _i of the configurable transmit power base station may be identified to have been used. Further, in the above example, rounding off the first decimal place of the value of the identified P _i and truncating may identify the transmission power by the base station apparatus is used in such rounding up. Further, when a discrete value is calculated from the identified transmission power value, the discrete value may be identified from the identified large transmission power value.

Control information detection section 2044 of the terminal device is allocated transmit power P ₁ detects the MCS information included in the transmission parameters of its own station of the signal (S31). The reference signal power measurement unit 3041 inputs the transmission power for each terminal device multiplexed by the estimated SC to the interference signal information identification unit 2045. The interference signal information identification unit 2045 identifies the MCS of the interference signal based on the transmission power for each terminal device multiplexed by SC as in the second embodiment (S21). Subsequent processing is the same as that of the second embodiment, and a description thereof will be omitted.

  In the present embodiment, the case where constant transmission power is applied in the allocation RB notified by one control information has been described. However, the present invention may not be constant transmission power in all allocation RBs, and may be determined in advance. The transmission power may be identified in units of RBG or subband, and in that case, MCS is identified in units of RBG or subband. Furthermore, it may be multiplexed by different terminal apparatuses and SCs in units of RBGs or subbands.

  In the present embodiment, a case has been described in which the base station apparatus identifies the transmission power assigned to each terminal apparatus multiplexed on the terminal apparatus by SC, and further identifies the MCS of the interference signal. However, SLIC or MLD is used for reception processing. Since the terminal apparatus does not require coding rate information, only the modulation multi-level number (Modulation Order) may be identified.

  As described above, in this embodiment, it is not necessary to notify the transmission power used at the time of multiplexing in the SC, and the overhead of control information can be reduced.

(Fourth embodiment)
In the present embodiment, an example will be described in which the transmission power of a desired signal is notified and the terminal device identifies an MCS candidate for an interference signal. First, the configuration example of the base station apparatus in this embodiment is the same as that of the second embodiment, and is shown in FIGS. Further, the configuration example of the terminal device in the present modification is the same as that of the second embodiment, and is shown in FIGS. Also, the flowchart of the reception process is the same as that of the previous embodiment, and is shown in FIG. Therefore, in the present embodiment, only different processing will be described, and description of similar processing will be omitted.

In the flowchart of FIG. 9, the information detection unit 2044 of the terminal device to which the transmission power P ₁ is assigned detects the MCS information and the transmission power P ₁ included in the transmission parameter of the signal addressed to itself (S20). Interference signal information identification unit 2045 identifies at MCS index _{I MCS2} as the MCS candidates of the interference signal MCS index of own station signals from the _{I MCS1 I MCS2 = I MCS1 -N} (P 1). N (P ₁ ) means that a combination of MCSs of terminal apparatuses multiplexed by SC is uniquely determined according to transmission power of a desired signal. Therefore, the terminal device is allocated transmit power P ₁ may identify the MCS of the interference signal when it is notified that the transmission power of the desired signal. Examples of N _{(P 1),} may be determined by _{N (P 1) = I BASE} + I OFFSET (P 1), I BASE is previously notified values etc. _{RRC, I OFFSET (P 1)} is is a value that depends on the transmission power P _1. 0 _{<P 1} ≦ 0.1 in the case of _{I OFFSET (P 1) = 0,0.1} <P 1 in the case of _{≦ 0.2 I OFFSET (P 1)} = 1,0.2 <P 1 ≦ 0 In the case of .3, I _OFFSET (P ₁ ) = 2 may be used. Also, in the MCS table of FIG. 12, when I _MCS1 = 22 and N (P ₁ ) = 15, the terminal apparatus determines that the MCS index I _MCS2 of the interference signal is 7, and the QPSK coding rate R (7).

Also, the interference signal information identification unit 2045 of the terminal device is allocated transmit power _{P 1} is the MCS index _{I MCS2} to be MCS candidate interference signal MCS index of own station signals from the _{I MCS1 I MCS2} = _{{I MCS1 -N 1 (P 1),} it MCS1 -N 1 (P 1) + 1, ..., I MCS1 -N 2 (P 1) may be}. This is a case where a terminal device to which transmission power P ₁ is allocated indicates a plurality of MCS candidates that may be used in an interference signal based on MCS and transmission power of a desired signal, and the terminal device interferes with a plurality of MCSs. Attempt to detect the signal. As an example of N ₁ (P ₁ ) and N ₂ (P ₁ ), N ₁ (P ₁ ) = I _BASE1 + I _OFFSET (P ₁ ), N ₂ (P ₁ ) = I _BASE2 + I _OFFSET (P ₁ ) I _BASE1 and I _BASE2 are values notified in advance by RRC or the like, and I _OFFSET (P ₁ ) is a value depending on the transmission power P ₁ . 0 _{<P 1} ≦ 0.1 in the case of _{I OFFSET (P 1) = 0,0.1} <P 1 in the case of _{≦ 0.2 I OFFSET (P 1)} = 1,0.2 <P 1 ≦ 0 In the case of .3, I _OFFSET (P ₁ ) = 2 may be used. In the MCS table of FIG. 12, when I _MCS1 = 22 and N ₁ (P ₁ ) = 15 and N ₂ (P ₁ ) = 13, the terminal apparatus has an MCS index I _MCS2 of the interference signal of 7 ˜9, and attempt error correction decoding of the interference signal at the QPSK coding rates R (7) to R (9).

  In the present embodiment, the case where constant transmission power is applied in the allocation RB notified by one control information has been described. However, the present invention may not be constant transmission power in all allocation RBs, and may be determined in advance. The transmission power may be identified in units of RBG or subband, and in that case, MCS is identified in units of RBG or subband. Furthermore, it may be multiplexed by different terminal apparatuses and SCs in units of RBGs or subbands.

  In the present embodiment, a case has been described in which the base station apparatus identifies the transmission power assigned to each terminal apparatus multiplexed on the terminal apparatus by SC, and further identifies the MCS of the interference signal. However, SLIC or MLD is used for reception processing. Since the terminal apparatus does not require coding rate information, only the modulation multi-level number (Modulation Order) may be identified.

In this embodiment, the example in which the base station apparatus notifies the MCS index of I _MCS1 and the transmission power P ₁ to the terminal apparatus to which the transmission power P ₁ is assigned has been described. However, the MCS index is set to I _MCS1 and the interference signal MCS. the index _{I MCS2} may identify a transmit power _{P 1.}

  As described above, in this embodiment, it is not necessary to notify the transmission power used at the time of multiplexing in the SC, and the overhead of control information can be reduced.

  The program that operates in the base station apparatus and the terminal apparatus related to the present invention is a program (a program that causes a computer to function) that controls the CPU and the like 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 the case of distribution in the market, the program can be stored and distributed in a portable recording medium, 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. Moreover, you may implement | achieve part or all of the base station apparatus and terminal device in embodiment mentioned above as LSI which 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.

  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.

  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.

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 | wireless reception part 107 ... Control information detection part 108 ... Radio | wireless resource control Unit 109 ... Control information generation unit 1011-1 to 1011-2 ... Error correction coding unit 1012-1 to 1012-2 ... Modulation unit 1013-1 to 1013-3 ... Transmission power control unit 1014 ... Signal multiplexing unit 1015 ... see Signal multiplexing unit 1016 ... Reference signal generation unit 1017 ... Control signal multiplexing unit 1018 ... 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 antenna 2041 ... Reference signal Signal separation unit 2042 ... Control information separation unit 2043 ... Assigned signal extraction unit 2044 ... Control information detection unit 2045 ... Interference signal information identification unit 2051 ... Interference signal detection unit 2052 ... Interference signal reproduction unit 2053 ... Interference removal unit 2054 ... Desired signal detection Unit 2054-1 ... propagation compensation unit 2054-2 ... demodulation unit 2054-3 ... decoding unit 3041 ... reference signal power estimation unit

Claims (10)

A base station device that transmits data signals to a plurality of terminal devices,
The base station apparatus includes at least a signal multiplexing unit that multiplexes data signals of the first terminal apparatus and the second terminal apparatus by superposition coding, and a data signal addressed to the second terminal apparatus with respect to the first terminal apparatus. A control information generation unit that generates control information including additional information related to the transmission information, and a transmission processing unit that transmits a signal multiplexed by the superposition coding,
The transmission processing unit includes the data signal of the second terminal device generated based on the transmission parameter associated with the additional information included in the control information generated by the control information generation unit, and the first terminal device A base station apparatus that transmits a signal obtained by superposition coding a data signal. The base station apparatus includes a transmission power control unit that controls transmission power of data signals transmitted to the plurality of terminal apparatuses multiplexed by superposition coding.
The additional information is a control value of transmission power assigned to the first terminal device or the second terminal device used in the transmission power control unit, and a transmission parameter associated with the additional information is addressed to the second The base station apparatus according to claim 1, wherein the modulation multi-level number and the coding rate are applied to the data signal.   3. The base station apparatus according to claim 2, wherein the modulation multi-value number and the coding rate applied to the data signal addressed to the second, which is a transmission parameter associated with the additional information, are a plurality of candidates. . The base station apparatus includes a transmission power control unit that controls transmission power of data signals transmitted to the plurality of terminal apparatuses multiplexed by superposition coding.
The additional information is a modulation multi-value number and a coding rate applied to a data signal addressed to the second terminal apparatus, and a transmission parameter associated with the additional information is used in the transmission power control unit. The base station apparatus according to claim 1, wherein the base station apparatus is a transmission power control value assigned to one terminal apparatus or the second terminal apparatus. The base station apparatus includes a transmission power control unit that controls transmission power of data signals transmitted to the plurality of terminal apparatuses multiplexed by superposition coding.
The additional information is a threshold adjustment value used when selecting a modulation multi-value number and a coding rate applied to a data signal addressed to the first terminal device, and a transmission parameter associated with the additional information is 2. The base station apparatus according to claim 1, wherein the transmission power control value used in the transmission power control unit, the number of modulation levels applied to the data signal addressed to the second terminal apparatus, and the coding rate. . The base station device includes a transmission power control unit that controls transmission power of a data signal to be transmitted to the plurality of terminal devices multiplexed by superposition coding, and a reference signal generation unit that generates a reference signal.
The reference signal generation unit performs transmission power control of a reference signal based on a transmission power control value of the second terminal device used in the transmission power control unit, and a transmission parameter associated with the additional information is the second parameter. The base station apparatus according to claim 1, wherein the number of modulation levels and the coding rate are applied to a data signal addressed to the terminal apparatus. 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 a data signal addressed to another terminal device and a signal multiplexed by superposition coding, a control information detection unit that detects control information transmitted from the base station device, and An interference signal information identifying unit for identifying a transmission parameter used for the data signal addressed to the other terminal device from information related to the data signal addressed to the other terminal device included in the control information;
The signal detection unit detects an interference signal using a transmission parameter used for a data signal addressed to the other terminal device, and detects a desired signal by removing the detected interference signal. .   The information related to the data signal addressed to the other terminal device detected by the control information detection unit is the number of modulation levels and the coding rate applied to the data signal of the other terminal device, and the interference signal information 8. The terminal apparatus according to claim 7, wherein the transmission parameter used for the data signal addressed to the other terminal apparatus identified by the identification unit is transmission power of the data signal addressed to the other terminal apparatus.   The information related to the data signal addressed to the other terminal device detected by the control information detection unit is an adjustment value of a threshold value used when selecting the modulation multi-value number and the coding rate, and the interference signal information identification unit 8. The transmission parameter used for the data signal addressed to the other terminal device to be identified is a transmission power, a modulation multi-level number, and a coding rate of the data signal addressed to the other terminal device. Terminal equipment.   The information related to the data signal addressed to the other terminal device detected by the control information detection unit is the transmission power of the data signal addressed to the other terminal device, and the other signal identified by the interference signal information identification unit 8. The terminal apparatus according to claim 7, wherein transmission parameters used for a data signal addressed to the terminal apparatus are a modulation multi-level number and a coding rate of the data signal addressed to the other terminal apparatus.

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