WO2017169368A1 - Base station, terminals and communication method - Google Patents

Abstract

Provided are a base station, terminals and a communication method with which throughput can be improved by reducing interference while reducing reception processing loads on the terminals. The base station communicates with a first terminal and a second terminal, and is provided with a receiving unit for receiving, from the first terminal, information indicating support for multiuser superposition transmission, and a transmitting unit for transmitting, to the first terminal and the second terminal, downlink data, wherein the receiving unit receives information indicating support for semi-persistent scheduling from the first terminal, and if the transmitting unit transmits the downlink by semi-persistent scheduling, the downlink data is transmitted to the first terminal and the second terminal using orthogonal multiple access.

Description

Base station apparatus, terminal apparatus and communication method

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

In communication systems such as LTE (Long Term Evolution) and LTE-A (LTE-Advanced) by 3GPP (Third Generation Partnership Project), multiple terminal devices are non-orthogonal in order to increase system capacity and improve communication opportunities. Studies on multi-user transmission based on multiplexing transmission technology and superposition coding are underway (Non-Patent Document 1). In such non-orthogonal multiple access (Non-Orthogonal Multiple Access), inter-user interference occurs, so the terminal apparatus removes or suppresses the inter-user interference. Techniques for removing or suppressing interference between users include interference cancellers that eliminate interference signals and maximum likelihood detection (Maximum Likelihood Detection). For example, in downlink non-orthogonal multiple access, a base station device (eNB (evolved Node B)) multiplexes and transmits modulation symbols addressed to a plurality of different terminal devices (UE (User Equipment), mobile station device). At this time, the transmission power of each modulation symbol is determined in consideration of reception power (reception quality) at the multiplexed terminal apparatus. The terminal apparatus can extract only the modulation symbol addressed to itself by demodulating, decoding and canceling the signal addressed to another terminal apparatus among the multiplexed transmission signals.

In downlink non-orthogonal multiple access, a terminal device needs control information such as power allocation information of a downlink transmission signal to other terminals multiplexed in order to remove or suppress inter-user interference. However, adding power allocation information to a control signal leads to an increase in downlink control signals. Furthermore, if there are many power allocation patterns that can be set by the base station apparatus, the number of bits required for the downlink control signal increases. On the other hand, when the terminal device detects an interference signal blindly, the number of power allocation patterns increases, so that the number of detection attempts increases and the load on the terminal device increases.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a base station apparatus, a terminal apparatus, and a base station apparatus capable of improving throughput by reducing interference while reducing the load of reception processing of the terminal apparatus. It is to provide a communication method.

In order to solve the above-described problems, the configurations of the base station apparatus, terminal apparatus, and communication method according to the present invention are as follows.

(1) One aspect of the present invention is a base station apparatus that communicates with a first terminal apparatus and a second terminal apparatus, and includes information indicating that multiuser superimposed transmission is supported from the first terminal apparatus. A receiving unit for receiving and a transmitting unit for transmitting downlink data to the first terminal device and the second terminal device, wherein the receiving unit supports semi-persistent scheduling from the first terminal device; When the transmitter transmits the downlink by semi-persistent scheduling, the downlink data is transmitted to the first terminal apparatus and the second terminal apparatus using orthogonal multi-access. It is characterized by.

(2) In addition, according to one aspect of the present invention, when the reception unit has not received information indicating that semi-persistent scheduling is supported from the first terminal apparatus, the multi-user superimposed transmission is applied. , Downlink data is transmitted to the first terminal device and the second terminal device.

(3) In addition, according to an aspect of the present invention, when the transmission unit transmits the downlink data to the first terminal device by dynamic scheduling, multi-user superimposed transmission is applied to the first terminal device. Transmitting downlink data to the apparatus and the second terminal apparatus.

(4) In addition, according to an aspect of the present invention, when the transmission unit transmits downlink data to the second terminal apparatus using semi-per system scheduling, the multi-user superimposed transmission is applied, The downlink data is transmitted to the first terminal device and the second terminal device.

(5) Moreover, according to one aspect of the present invention, the transmission unit transmits downlink data to the second terminal apparatus using semi-per system scheduling, and downlink data transmission of the first terminal apparatus is performed. When the semi-persistent scheduling interval for the first terminal device and the semi-persistent scheduling interval for downlink data transmission of the first terminal device are the same, multi-user superimposed transmission is applied, and the first terminal device and the second terminal device And transmitting downlink data to the terminal device.

(6) Further, according to one aspect of the present invention, the transmission unit transmits downlink data to the second terminal apparatus using semi-per system scheduling, and downlink data transmission of the first terminal apparatus is performed. When the semi-persistent scheduling interval for the first terminal apparatus is n times or 1 / n times the semi-persistent scheduling interval for downlink data transmission of the first terminal device (n is a natural number), Applying, downlink data is transmitted to the first terminal device and the second terminal device.

(7) Moreover, one aspect of the present invention is a communication method of a base station apparatus that communicates with a first terminal apparatus and a second terminal apparatus, and supports multi-user superimposed transmission from the first terminal apparatus. A receiving step for receiving information indicating the above and a transmitting step for transmitting downlink data to the first terminal device and the second terminal device, and supporting semi-persistent scheduling from the first terminal device When transmitting the downlink with semi-persistent scheduling, transmitting downlink data to the first terminal device and the second terminal device using orthogonal multi-access, Features.

(8) One aspect of the present invention is a terminal device that communicates with a base station device, wherein the base station device transmits information indicating that multi-user superimposed transmission is supported, and the base station device A receiving unit that receives downlink data, and when the transmitting unit transmits information indicating that semi-persistent scheduling is supported to the base station apparatus, the receiving unit uses a downlink that uses semi-persistent scheduling. The data is assumed to be using orthogonal multi-access.

(9) In addition, according to an aspect of the present invention, when the reception unit receives downlink control information, the reception unit demodulates the downlink data on the assumption that orthogonal multi-access or multi-user superimposed transmission is used. It is characterized by this.

(10) In addition, according to one aspect of the present invention, when the receiving unit demodulates the downlink data on the assumption that multi-user superimposed transmission is used, a process of removing or suppressing interference is performed. Features.

(11) One aspect of the present invention is a communication method for a terminal apparatus that communicates with a base station apparatus, wherein the base station apparatus transmits information indicating that multiuser superimposed transmission is supported, and the base station A receiving step of receiving downlink data from a station apparatus, and transmitting information indicating that semi-persistent scheduling is supported to the base station apparatus, downlink data using semi-persistent scheduling is orthogonal It is assumed that access is used.

According to the present invention, it is possible to reduce the interference signal while reducing the load of reception processing of the terminal device, and to improve the throughput and the communication opportunity of the terminal device.

It is a figure which shows the example of the communication system which concerns on 1st Embodiment. It is a figure which shows the example of the power ratio of the terminal device by which the non-orthogonal multiplexing which concerns on 1st Embodiment is carried out. It is a schematic block diagram which shows the structure of the base station apparatus which concerns on 1st Embodiment. It is a schematic block diagram which shows the structure of the terminal device which concerns on 1st Embodiment. It is a figure which shows the example of the flowchart in which the base station apparatus which concerns on 1st Embodiment performs multiuser superimposed transmission. It is a figure which shows another example of the flowchart in which the base station apparatus which concerns on 1st Embodiment performs multiuser superposition transmission. It is a figure which shows another example of the flowchart in which the base station apparatus which concerns on 1st Embodiment performs multiuser superposition transmission. It is a figure which shows another example of the flowchart in which the base station apparatus which concerns on 1st Embodiment performs multiuser superposition transmission. It is a figure which shows the example of the flowchart in which the base station apparatus which concerns on 2nd Embodiment performs multiuser superposition transmission. It is a figure which shows another example of the flowchart in which the base station apparatus which concerns on 2nd Embodiment performs multiuser superposition transmission. It is a figure which shows another example of the flowchart in which the base station apparatus which concerns on 2nd Embodiment performs multiuser superposition transmission.

(First embodiment)
The communication system in this embodiment includes a base station device (transmitting device, cell, serving cell, transmission point, transmission antenna group, transmission antenna port group, component carrier, eNodeB) and terminal device (terminal, mobile terminal, reception point, reception terminal). , Receiving device, receiving antenna group, receiving antenna port group, UE).

In this embodiment, “X / Y” includes the meaning of “X or Y”. In the present embodiment, “X / Y” includes the meanings of “X and Y”. In the present embodiment, “X / Y” includes the meaning of “X and / or Y”.

FIG. 1 is a diagram illustrating an example of a communication system according to the present embodiment. As shown in FIG. 1, the communication system according to the present embodiment includes a base station device 1A and terminal devices 2A and 2B. The coverage 1-1 is a range (communication area) in which the base station device 1A can be connected to the terminal device. The terminal devices 2A and 2B are also collectively referred to as the terminal device 2.

In FIG. 1, the following uplink physical channels are used in uplink wireless communication from the terminal apparatus 2 to the base station apparatus 1A. The uplink physical channel is used for transmitting information output from an upper layer.
・ Physical uplink control channel (PUCCH)
・ Physical Uplink Shared Channel (PUSCH)
・ Physical Random Access Channel (PRACH)

The PUCCH is used for transmitting uplink control information (Uplink Control Information: UCI). A plurality of UCI formats are defined for transmission of uplink control information. That is, fields for uplink control information are defined in the UCI format and mapped to information bits.

The uplink control information includes ACK (a positive acknowledgment) or NACK (a negative acknowledgment) (ACK / NACK) for downlink data (downlink transport block, Downlink-Shared Channel: DL-SCH). ACK / NACK for downlink data is also referred to as HARQ-ACK and HARQ feedback. The uplink control information includes a scheduling request (SR: “Scheduling” Request).

The uplink control information includes channel state information for downlink (Channel State Information: CSI). The uplink control information includes a scheduling request (Scheduling Request: SR) used for requesting resources of the uplink shared channel (Uplink-Shared Channel: UL-SCH). The channel state information includes a rank index RI (Rank Indicator) designating a suitable spatial multiplexing number, a precoding matrix indicator PMI (Precoding Matrix Indicator) designating a suitable precoder, and a channel quality index CQI designating a suitable transmission rate. (Channel Quality Indicator).

The channel quality indicator CQI (hereinafter referred to as CQI value) can be a suitable modulation scheme (for example, QPSK, 16QAM, 64QAM, 256QAM, etc.) and a coding rate in a predetermined band. The CQI value can be an index (CQI Index) determined by the modulation scheme and coding rate. The CQI value can be predetermined by the system.

Note that the rank index and the precoding quality index can be determined in advance by the system. The rank index and the precoding matrix index can be indexes determined by the spatial multiplexing number and precoding matrix information. Note that the values of the rank index, the precoding matrix index, and the channel quality index CQI are collectively referred to as CSI values.

The PUSCH is used for transmitting uplink data (uplink transport block, UL-SCH). Moreover, PUSCH may be used to transmit ACK / NACK and / or channel state information together with uplink data. Moreover, PUSCH may be used in order to transmit only uplink control information.

Also, PUSCH is used to transmit an RRC message. The RRC message is information / signal processed in a radio resource control (Radio-Resource-Control: -RRC) layer. The PUSCH is used to transmit a MAC CE (Control Element). Here, the MAC CE is information / signal processed (transmitted) in the medium access control (MAC) layer.

For example, the power headroom may be included in the MAC CE and reported via PUSCH. That is, the MAC CE field is used to indicate the power headroom level.

PRACH is used to transmit a random access preamble.

In uplink wireless communication, an uplink reference signal (Uplink Reference Signal: UL SRS) is used as an uplink physical signal. The uplink physical signal is not used for transmitting information output from the upper layer, but is used by the physical layer. The uplink reference signal includes DMRS (Demodulation Reference Signal) and SRS (Sounding Reference Signal).

DMRS is related to transmission of PUSCH or PUCCH. For example, the base station device 1A uses DMRS to perform channel correction when demodulating PUSCH or PUCCH. SRS is not related to PUSCH or PUCCH transmission. For example, the base station apparatus 1A uses SRS to measure the uplink channel state.

In FIG. 1, the following downlink physical channels are used in downlink wireless communication from the base station apparatus 1A to the terminal apparatus 2. The downlink physical channel is used for transmitting information output from an upper layer.
・ Physical Broadcast Channel (PBCH)
・ Physical Control Format Indicator Channel (PCFICH)
-Physical hybrid automatic repeat request indicator channel (PHICH)
• Physical downlink control channel (PDCCH)
-Enhanced physical downlink control channel (EPDCCH)
・ Physical downlink shared channel (PDSCH)

The PBCH is used to broadcast a master information block (Master Information Block: MIB, Broadcast Channel: BCH) that is commonly used by terminal devices. The PBCH includes information such as a system band, a system frame number (SFN: System Frame number), and the number of transmission antennas used by the eNB. PCFICH is used for transmitting information indicating a region (for example, the number of OFDM symbols) used for transmission of PDCCH.

PHICH is used to transmit ACK / NACK for uplink data (transport block, codeword) received by the base station apparatus 1A. That is, PHICH is used to transmit a HARQ indicator (HARQ feedback) indicating ACK / NACK for uplink data. ACK / NACK is also referred to as HARQ-ACK. The terminal device 2 notifies the received ACK / NACK to the higher layer. ACK / NACK is ACK indicating that the data has been correctly received, NACK indicating that the data has not been correctly received, and DTX indicating that there is no corresponding data. Further, when there is no PHICH for the uplink data, the terminal device 2 notifies the upper layer of ACK.

PDCCH and EPDCCH are used to transmit downlink control information (DCI: “Downlink” Control “Information”). A plurality of DCI formats are defined for transmission of downlink control information. That is, fields for downlink control information are defined in the DCI format and mapped to information bits.

For example, a DCI format 1A used for scheduling one PDSCH (transmission of one downlink transport block) in one cell is defined as a DCI format for the downlink.

For example, the DCI format for downlink includes information on PDSCH resource allocation, information on MCS (Modulation and Coding Scheme) for PDSCH, and downlink control information such as TPC command for PUCCH. Here, the DCI format for the downlink is also referred to as a downlink grant (or downlink assignment).

For example, as the DCI format for uplink, DCI format 0 used for scheduling one PUSCH (transmission of one uplink transport block) in one cell is defined.

For example, the uplink DCI format includes uplink control information such as information on PUSCH resource allocation, information on MCS for PUSCH, and TPC command for PUSCH. The DCI format for the uplink is also referred to as uplink grant (or uplink assignment).

The DCI format for the uplink can be used to request downlink channel state information (CSI: Channel State Information, also referred to as reception quality information). The channel state information includes a rank indicator (RI: Rank Indicator) that specifies a suitable spatial multiplexing number, a precoding matrix indicator (PMI: Precoding Matrix Indicator) that specifies a suitable precoder, and a channel quality index that specifies a suitable transmission rate. (CQI: Channel Quality Indicator), precoding type indicator (PTI: Precoding type Indicator), etc.

The DCI format for uplink can be used for setting indicating an uplink resource that maps a channel state information report (CSI feedback) report that a terminal apparatus feeds back to a base station apparatus. For example, the channel state information report can be used for setting indicating an uplink resource that periodically reports channel state information (Periodic CSI). The channel state information report can be used for mode setting (CSI report mode) for periodically reporting the channel state information.

For example, the channel state information report can be used for setting indicating an uplink resource for reporting irregular channel state information (Aperiodic CSI). The channel state information report can be used for mode setting (CSI report mode) for reporting the channel state information irregularly. The base station apparatus can set either the periodic channel state information report or the irregular channel state information report. Further, the base station apparatus can set both the periodic channel state information report and the irregular channel state information report.

The DCI format for the uplink can be used for setting indicating the type of channel state information report that the terminal apparatus feeds back to the base station apparatus. Types of channel state information reports include wideband CSI (for example, Wideband CQI) and narrowband CSI (for example, Subband CQI).

When the PDSCH resource is scheduled using the downlink assignment, the terminal apparatus receives the downlink data on the scheduled PDSCH. In addition, when PUSCH resources are scheduled using an uplink grant, the terminal apparatus transmits uplink data and / or uplink control information using the scheduled PUSCH.

PDSCH is used to transmit downlink data (downlink transport block, DL-SCH). PDSCH is used to transmit a system information block type 1 message. The system information block type 1 message is cell specific (cell specific) information.

PDSCH is used to transmit a system information message. The system information message includes a system information block X other than the system information block type 1. The system information message is cell specific (cell specific) information.

PDSCH is used to transmit an RRC message. The RRC message transmitted from the base station apparatus may be common to a plurality of terminal apparatuses in the cell. Further, the RRC message transmitted from the base station device 1A may be a message dedicated to a certain terminal device 2 (also referred to as dedicated signaling). That is, user device specific (user device specific) information is transmitted to a certain terminal device using a dedicated message. PDSCH is used to transmit MAC CE.

Here, the RRC message and / or MAC CE is also referred to as higher layer signaling.

PDSCH can be used to request downlink channel state information. The PDSCH can be used to transmit an uplink resource that maps a channel state information report (CSI feedback report) that the terminal device feeds back to the base station device. For example, the channel state information report can be used for setting indicating an uplink resource for reporting periodic channel state information (Periodic CSI) / aperiodic channel state information (Aperiodic CSI). The channel state information report can be used for mode setting (CSI report mode) for reporting the channel state information regularly / irregularly.

The types of downlink channel state information reports include wideband CSI (for example, Wideband CSI) and narrowband CSI (for example, Subband CSI). The broadband CSI calculates one channel state information for the system band of the cell. In the narrowband CSI, the system band is divided into predetermined units, and one channel state information is calculated for the division.

In downlink radio communication, a synchronization signal (Synchronization signal: SS) and a downlink reference signal (Downlink Reference Signal: DL RS) are used as downlink physical signals. The downlink physical signal is not used to transmit information output from the upper layer, but is used by the physical layer.

The synchronization signal is used for the terminal device to synchronize the downlink frequency domain and time domain. Also, the downlink reference signal is used by the terminal device for channel correction of the downlink physical channel. For example, the downlink reference signal is used by the terminal device to calculate downlink channel state information.

The downlink reference signal includes CRS (Cell-specific Reference Signal: Cell-specific reference signal), URS related to PDSCH (UE-specific Reference Signal: terminal-specific reference signal, terminal device-specific reference signal), DMRS related to EPDCCH. (Demodulation Reference Signal), NZP CSI-RS (Non-Zero Power Chanel State Information Information Reference Signal), and ZP CSI-RS (Zero Power Chanel State Information Information Reference Signal).

The CRS is transmitted scattered over the entire band of the subframe and is used to demodulate PBCH / PDCCH / PHICH / PCFICH / PDSCH. The URS associated with the PDSCH is transmitted in subframes and bands used for transmission of the PDSCH with which the URS is associated, and is used to demodulate the PDSCH with which the URS is associated. CRS can also be used for measurement.

DMRS related to EPDCCH is transmitted in subframes and bands used for transmission of EPDCCH related to DMRS. DMRS is used to demodulate the EPDCCH with which DMRS is associated.

NZP CSI-RS resources are set by the base station apparatus 1A. For example, the terminal device 2 performs signal measurement (channel measurement) using NZP CSI-RS. The resource of ZP CSI-RS is set by the base station apparatus 1A. The base station apparatus 1A transmits ZP CSI-RS with zero output. For example, the terminal device 2 measures interference in a resource supported by NZP CSI-RS.

MBSFN (Multimedia Broadcast Multicast Service Single Frequency Network) RS is transmitted in the entire bandwidth of the subframe used for PMCH transmission. The MBSFN RS is used for PMCH demodulation. PMCH is transmitted through an antenna port used for transmission of MBSFN RS.

Here, the downlink physical channel and the downlink physical signal are collectively referred to as a downlink signal. Also, the uplink physical channel and the uplink physical signal are collectively referred to as an uplink signal. Also, the downlink physical channel and the uplink physical channel are collectively referred to as a physical channel. Also, the downlink physical signal and the uplink physical signal are collectively referred to as a physical signal.

BCH, UL-SCH and DL-SCH are transport channels. A channel used in the MAC layer is referred to as a transport channel. A transport channel unit used in the MAC layer is also referred to as a transport block (Transport Block: TB) or a MAC PDU (Protocol Data Unit). The transport block is a unit of data that is delivered (delivered) by the MAC layer to the physical layer. In the physical layer, the transport block is mapped to a code word, and an encoding process or the like is performed for each code word.

The base station apparatus can apply scheduling schemes such as dynamic scheduling (DS: Dynamic Scheduling) and semi-persistent scheduling (SPS: Semi-Persistent Scheduling) in uplink and downlink communication with the communication device. The base station apparatus 1A schedules the terminal apparatuses 2A and 2B using DS. Base station apparatus 1A schedules terminal apparatus 2A using DS, and schedules terminal apparatus 2B using SPS. The base station apparatus 1A schedules the terminal apparatus 2A using SPS and schedules the terminal apparatus 2B using DS. Base station apparatus 1A schedules terminal apparatuses 2A and 2B using SPS.

In DS, the base station apparatus 1A dynamically allocates frequency / time / space resources for data transmission to the terminal apparatus 2 according to the flow rate of the terminal apparatus 2 and the service quality (QoS: “Quality” of Service). In the DS, the base station apparatus 1A dynamically allocates resources to each terminal apparatus in resource block units configured with a predetermined frequency and a predetermined time. 1 A of base station apparatuses notify the resource for transmitting PDSCH / PUSCH etc., such as resource allocation, using PDCCH transmitted to each terminal device.

In SPS, the base station apparatus 1A allocates frequency / time / space resources for data transmission to the terminal apparatus 2 at a constant cycle. For example, SPS is used to provide higher layer application services (eg, VoIP (Voice over Internet Protocol)) that generate data periodically. In the SPS, the base station apparatus 1A uses the PDCCH transmitted to each terminal apparatus to notify the period for transmitting PDSCH / PUSCH, the resource allocation, and the like. Thereafter, the PDSCH / PUSCH is periodically transmitted based on the period or the like. In SPS, since resources are allocated to terminal devices at a constant period, the base station device is prevented from transmitting control information on the PDCCH, and system scheduling efficiency is improved. In other words, since the SPS allocates resources to the terminal device at a fixed period, the terminal apparatus periodically transmits without monitoring the PDCCH, and ensures that each period transmission is a transmission of new data. be able to.

The base station apparatus according to the present embodiment can multiplex a plurality of terminal apparatuses without dividing resources in time, frequency and space (for example, antenna port, beam pattern, precoding pattern). Multiplexing multiple terminal devices without dividing resources in time / frequency / space is referred to as non-orthogonal multiple access (NOMA: Non Orthogonal Multiple Access), multi-user superimposed transmission (MUST: Multiuser Superposition Transmission), non- Also called orthogonal multiplexing. In the following, a case where two terminal apparatuses are non-orthogonal multiplexed will be described, but the present invention is not limited to this, and three or more terminal apparatuses can be non-orthogonal multiplexed.

An example in which the base station apparatus 1A of FIG. 1 performs non-orthogonal multiplexing of the terminal apparatus 2A and the terminal apparatus 2B will be described. Unless otherwise noted, it is assumed that the terminal device 2A is closer to the base station device 1A or has better reception quality than the terminal device 2B. The terminal device 2A is also called a terminal device (near-UE) close to the base station device, and the terminal device 2B is also called a terminal device (Far-UE) far from the base station device. In the following description, the PDSCH for the terminal device 2A is also referred to as PDSCH1 (first PDSCH), and the PDSCH for the terminal device 2B is also referred to as PDSCH2 (second PDSCH). In the following description, the base station apparatus mainly explains the case where MUST is performed using PDSCH, but MUST can also be applied to other channels (for example, PMCH, PDCCH, EPDCCH). In addition, when performing MUST on a plurality of channels, MUST can be applied using a different superposition transmission method or MUST category (described later) for each channel. When MUST is applied in a plurality of channels, different reception schemes can be assumed for each channel. For example, a symbol level reception scheme may be used for PDSCH, and a codeword level reception scheme for PMCH.

When the base station apparatus 1A transmits the terminal apparatuses 2A and 2B by non-orthogonal multiplexing, there are several transmission methods. For example, the base station apparatus 1A can superimpose and transmit to the terminal apparatuses 2A and 2B using QPSK / 16QAM / 64QAM / 256QAM mapping of the same constellation. Such a superposition transmission method is also referred to as MUST category 1. In this case, the constellation obtained by combining the terminal devices 2A and 2B is a non-Gray code constellation. Furthermore, the base station apparatus 1A can allocate various ratios of power to the terminal apparatuses 2A and 2B. In this case, the terminal device 2A removes or suppresses the interference signal on the assumption that the mapping pattern of the terminal device 2B is the same as itself.

For example, the base station apparatus 1A can superimpose and transmit to the terminal apparatuses 2A and 2B using different constellations so that the constellation obtained by combining the terminal apparatuses 2A and 2B becomes a gray code constellation. Such a superposition transmission method is also referred to as MUST category 2. In this case, the base station apparatus 1A can allocate various ratios of power to the terminal apparatuses 2A and 2B. In this case, the terminal device 2A removes or suppresses the interference signal on the assumption that the mapping pattern of the terminal device 2B is different from itself.

For example, the base station apparatus 1A can map and transmit the transmission bit string addressed to the terminal apparatuses 2A and 2B so as to be an existing QPSK / 16QAM / 64QAM / 256QAM constellation. Such a superposition transmission method is also referred to as MUST category 3. In this case, the base station apparatus 1A can allocate the power of the terminal apparatuses 2A and 2B according to the constellation to be mapped. In this case, the terminal device 2A demodulates the existing mapping and sets a part of the obtained bits as a bit addressed to itself.

When the base station apparatus 1A transmits the signals of the terminal apparatus 2A and the terminal apparatus 2B by non-orthogonal multiplexing, PDSCH1 and PDSCH2 interfere with each other. For example, the base station apparatus 1A allocates more power to the terminal apparatus 2B that is a Far-UE than the terminal apparatus 2A that is a near-UE. In this case, at least the terminal device 2A receives a strong interference signal, and handles, removes, or suppresses the interference signal. Such interference signals are referred to as multi-user interference, inter-user interference, interference due to multi-user transmission, co-channel interference, and the like. In order to remove or suppress the interference signal, for example, an interference signal replica signal obtained from the demodulation or decoding result of the interference signal is subtracted from the received signal. In order to remove or suppress the interference signal, SLIC (Symbol Level Interference Cancellation) for canceling interference based on the demodulation result of the interference signal, CWIC (Codeword Level Interference Cancellation) for canceling interference based on the decoding result of the interference signal, transmission signal candidate Likelihood detection (ML: maximum likelihood, R-ML: Reduced complexity maximumlikelihood), EMMSE-IRC (Enhanced Minimum Mean Square Error-Interference Rejection Combining) that suppresses interference signals by linear operation )and so on.

The base station apparatus can transmit a common terminal apparatus specific reference signal to a plurality of terminal apparatuses that perform non-orthogonal multiplexing. That is, the base station apparatus can transmit a reference signal to a plurality of terminal apparatuses using the same resource and the same reference signal sequence in time / frequency / space. Further, the base station apparatus can set the transmission mode for the terminal apparatus. The base station apparatus can perform transmission by MUST when setting a predetermined transmission mode. Further, the base station apparatus may not perform transmission by MUST when a transmission mode other than the predetermined transmission mode or MUST is not set. In other words, the terminal device can determine whether or not the transmission is based on MUST based on the set transmission mode and the presence / absence of MUST setting.

When the base station apparatus sets the CRS-based transmission mode for the terminal apparatus 2A, the base station apparatus can set the CRS-based transmission mode for the terminal apparatus 2B. When the base station apparatus sets the DMRS-based transmission mode for the terminal apparatus 2A, the base station apparatus can set the CRS / DMRS-based transmission mode for the terminal apparatus 2B. The CRS-based transmission mode is a transmission mode that demodulates using CRS, and is, for example, one of transmission modes 1 to 6. However, it is not limited to any one of these transmission modes. The DMRS-based transmission mode is a transmission mode that is demodulated using a terminal-specific reference signal, and is, for example, one of transmission modes 8 to 10. However, it is not limited to any one of these transmission modes.

Each of the terminal devices 2A and 2B may be set to the MUST transmission mode, may not be set to the MUST transmission mode, may be configured to have MUST transmission, or may not be configured to MUST transmission. , Signal detection by R-ML or SLIC is essential, and R-ML or SLIC may be omitted. Further, the terminal apparatuses 2A and 2B may be terminals capable of MUST and terminals not capable of MUST, may receive information related to interference signals using a control signal, and may not receive information related to interference signals using a control signal.

The terminal device 2A can detect a parameter necessary for removing or suppressing the interference signal from the base station device or by blind detection. The terminal device 2B may or may not remove or suppress the interference signal. When the terminal device 2B does not remove or suppress the interference signal, since the interference signal power is relatively small, the terminal device 2B can demodulate the signal addressed to itself without knowing the parameter regarding the interference signal. When the base station apparatus 1A performs non-orthogonal multiplexing of the terminal apparatuses 2A and 2B, the terminal apparatus 2A needs to have a function of removing or suppressing interference signals due to non-orthogonal multiplexing, but the terminal apparatus 2B performs interference removal or suppression. It may or may not have a function. In other words, the base station apparatus 1A can non-orthogonally multiplex a terminal apparatus that supports non-orthogonal multiplexing and a terminal apparatus that does not support non-orthogonal multiplexing. In other words, the base station device 1A can non-orthogonally multiplex terminal devices for which different transmission modes are set. Therefore, the communication opportunity of each terminal device can be improved.

The base station apparatus 1A transmits information (assist information, auxiliary information, control information, and setting information in MUST) regarding the terminal apparatus (terminal apparatus 2B in FIG. 1) that causes interference to the terminal apparatus 2A. The base station apparatus 1A can transmit information (MUST assist information, MUST information) about the terminal apparatus that causes interference by using a higher layer signal or a physical layer signal (control signal, PDCCH, EPDCCH).

The MUST assist information includes information on PA, information on transmission mode (transmission method), information on transmission power of terminal-specific reference signal, power allocation information on PDSCH, information on PMI, PA of serving cell, terminal-specific reference signal of serving cell. Information related to transmission power, modulation scheme, MCS (Modulation and Coding Scheme), redundancy version, C (Cell) -RNTI (Radio Network Temporary Identifier), SPS (Semi-Persistent Scheduling) C-RNTI, MUST-RNTI, base station equipment Information indicating whether the terminal device is near (near-UE) or far terminal device (Far-UE), MUST category (method), codeword index, layer index, transport block index, part or all of physical channel information included.

PA is information based on a transmission power ratio (power offset) between PDSCH and CRS in an OFDM symbol in which CRS is not arranged. The information regarding the transmission mode (transmission method) is such that the terminal device 2A knows the transmission mode of the interference signal, such as the transmission mode of the interference signal and the transmission mode candidates that the base station device 1A can set (possibly set). Assist information. The transmission method includes transmission diversity, large delay CDD (Cyclic Delay Delay), Open-loop MIMO, Closed-loop MIMO, and the like. The codeword / layer / transport block index is information indicating which codeword / layer / transport block the MUST is applied to when transmitted by a plurality of codewords / layers / transport blocks. The physical channel information is information indicating which physical channel the MUST is applied to, and can indicate, for example, PDSCH or PMCH.

The terminal device close to the base station device and the distant terminal device may mean that the close terminal device performs interference removal or suppression by MUST, and the distant terminal device does not cancel or suppress interference by MUST. A terminal device close to a base station device and a distant terminal device may mean that a near terminal device has a smaller allocated power than a distant terminal. Further, a terminal device close to a base station device and a distant terminal device may mean that a near terminal device has a power ratio smaller than 0.5 and a far terminal device has a power ratio of 0.5 or more. . A terminal device close to a base station device and a distant terminal device may mean that a close terminal device has a lower modulation multi-level number or MCS than a distant terminal.

Also, one value (candidate, list) may be set for each of the parameters included in the above MUST assist information, or a plurality of values (candidates, list) may be set. When a plurality of values are set, the terminal device detects (blind detection) a parameter set in the interference signal from the plurality of values. Some or all of the parameters included in the MUST assist information are transmitted as higher layer signals. Some or all of the parameters included in the MUST assist information may be transmitted as a physical layer signal.

MUST assist information may be used when performing various measurements. The measurement includes RRM (Radio Resource Management) measurement and CSI (Channel State Information) measurement.

When the terminal device 2A supports carrier aggregation (Carrier Aggregation: CA) for performing broadband transmission by combining a plurality of component carriers (CC: Component Carrier), the base station device 1A includes a primary cell (Primary Cell: PCell) and MUST assist information for a secondary cell (Secondary Cell: SCell) can be set. Moreover, 1 A of base station apparatuses can also set or transmit MUST assist information only to PCell.

When the terminal apparatus 2A / 2B supports NAICS (Network Assisted Interference Cancellation Suppression) that removes or suppresses CRS / PDSCH interference from the adjacent cell, the base station apparatus transmits the terminal apparatus 2A / 2B to the terminal apparatus 2A / 2B from the adjacent cell. The NAICS assist information used for removing the interference can be transmitted. The NAICS assist information includes physical cell ID, number of CRS antenna ports, MBSFN subframe configuration, PA list, PB, transmission mode list, and part or all of resource allocation granularity. Note that PB represents a power ratio of PDSCH in an OFDM symbol in which CRS is not arranged and in an OFDM symbol in which CRS is not arranged.

Note that the base station apparatus can not simultaneously set MUST assist information and NAICS assist information for the terminal apparatus. When NAICS assist information is set, MUST assist information is not set. When MUST assist information is set, NAICS assist information is not set. When the MUST assist information and the NAICS assist information are set at the same time, the terminal device can remove or suppress interference based on one of the assist information. For example, when the MUST assist information and the NAICS assist information are set at the same time, the terminal device can remove or suppress interference based only on the MUST assist information or the NAICS assist information.

The terminal device 2A receives the MUST assist information with the upper layer signal and / or the physical layer signal, detects (identifies) a parameter for removing or suppressing the interference signal based on the MUST assist information, and The interference signal is removed or suppressed using the parameter. Note that the terminal device 2A can detect parameters that are not included in the MUST information by blind detection that tries to detect parameter candidates in order.

In the power allocation information, a table or list is set in the upper layer or the physical layer, and the base station apparatus can indicate the power ratio to the terminal apparatus by signaling its index with a signal of the physical layer. The terminal device can obtain the power ratio by referring to the table or list from the MUST setting and index received from the base station device.

FIG. 2 is a diagram illustrating an example of the power ratio of the non-orthogonal multiplexed terminal apparatus according to the present embodiment. For example, when the value of the table is 1, the power ratio of the own device can be obtained as 0.2, and the power ratio of the terminal device that is a MUST pair can be obtained as 1−0.2 = 0.8. Note that the power ratio of the pair may also be shown in a table. The table may be generated so as to include power ratio = 0. in this case. Since the power ratio of the paired terminal devices is 0, it can be shown that there is no interference signal.

The information indicating that MUST can be applied may indicate a predetermined power allocation. For example, when MUST is applied, the power ratio of the multiplexed terminal apparatuses is preset as 20:80. In this case, when information indicating that MUST can be applied is transmitted from the terminal device 2A to the base station device 1A or from the base station device 1A to the terminal device 2A, the terminal device 2A is connected to the terminal device 2A and the terminal device 2B. Is assumed to be 20:80.

The base station apparatus can change the content of the downlink control information according to the transmission mode. For example, in the case of the CRS-based transmission mode, the base station apparatus transmits power allocation information included in downlink control information. In the case of DMRS base, the base station apparatus replaces the bits used in the power allocation information in the case of the CRS base transmission mode with other information such as the antenna port and PMI of the interference signal. In other words, the terminal apparatus can obtain power allocation information from a certain field included in the downlink control information when configured in the CRS-based transmission mode, and an interference signal antenna in the DMRS-based transmission mode. Other information such as port and PMI can be obtained. Further, when the terminal device is in the DMRS-based transmission mode, the power allocation information can be obtained from the terminal device-specific reference signal of the terminal device that becomes the MUST pair with itself.

FIG. 3 is a schematic block diagram showing the configuration of the base station apparatus 1A according to the present embodiment. The base station apparatus 1A includes an upper layer processing unit (upper layer processing step) 101, a control unit (control step) 102, transmission units (transmission steps) 103-1, 103-2, a reception unit (reception step) 104, and a transmission antenna. 105-1 and 105-2, and a receiving antenna 106-1. The upper layer processing unit 101 includes a radio resource control unit (radio resource control step) 1011 and a scheduling unit (scheduling step) 1012. The transmission unit 103-1 generates a transmission signal to the terminal device 2A. The transmission unit 103-2 generates a transmission signal to the terminal device 2B. The transmission units 103-1 and 103-2 are also collectively referred to as a transmission unit 103. The transmission antennas 105-1 and 105-2 are also collectively referred to as a transmission antenna 105.

The transmission unit 103 includes an encoding unit (encoding step) 1031, a modulation unit (modulation step) 1032, a downlink reference signal generation unit (downlink reference signal generation step) 1033, a multiplexing unit (multiplexing step) 1034, and a radio transmission unit (Wireless transmission step) 1035 is included. The reception unit 104 includes a wireless reception unit (wireless reception step) 1041, a demultiplexing unit (demultiplexing step) 1042, a demodulation unit (demodulation step) 1043, and a decoding unit (decoding step) 1044.

The upper layer processing unit 101 includes a medium access control (Medium Access Control: MAC) layer, a packet data integration protocol (Packet Data Convergence Protocol: PDCP) layer, a radio link control (Radio Link Control: RLC) layer, a radio resource control (Radio) Processes higher layers than physical layer such as Resource (Control: RRC) layer. Upper layer processing section 101 generates information necessary for controlling transmission section 103 and reception section 104 and outputs the information to control section 102.

The upper layer processing unit 101 receives information related to the terminal device such as the terminal device function (UE capability) from the terminal device 2 (via the receiving unit 104). In other words, the terminal apparatus transmits its own function to the base station apparatus using an upper layer signal. The information regarding the terminal device includes information indicating whether or not the terminal device supports a predetermined function, or information indicating that the terminal device is introduced into the predetermined function and the test is completed. Whether or not to support a predetermined function includes whether or not the installation and test for the predetermined function have been completed.

For example, when a terminal device supports a predetermined function, the terminal device transmits information (parameters) indicating whether the predetermined function is supported. When the terminal device does not support the predetermined function, the terminal device does not transmit information (parameter) indicating whether or not the predetermined device is supported. That is, whether or not to support the predetermined function is notified by whether or not information (parameter) indicating whether or not to support the predetermined function is transmitted. Note that information (parameter) indicating whether or not to support a predetermined function may be notified using 1 bit of 1 or 0.

The information related to the terminal device includes information indicating that MUST is supported and information indicating that SPS is supported. When there are a plurality of functions corresponding to MUST, the terminal device can transmit information indicating whether to support each function. Functions that support MUST include the ability to remove or suppress multi-user interference (PDSCH interference), the ability to support multiple tables indicating antenna ports, scrambling identities, and the number of layers, and a predetermined number of antenna ports , Capability corresponding to the number of CCs and resource blocks of carrier aggregation, capability corresponding to a predetermined transmission mode, capability corresponding to SPS (MUST corresponding to SPS Part or all of information indicating support and information indicating support of MUST that does not support SPS. The capability corresponding to the predetermined transmission mode is, for example, a combination of transmission modes applicable to MUST, whether the transmission mode can eliminate or suppress interference of MUST, and the like. The terminal apparatus can transmit the supported MUST applicable channel to the base station apparatus. The channels applicable to MUST are, for example, PDSCH and PDSCH superposition transmission, PMCH and PMCH superposition transmission, PDCCH and PDCCH superposition transmission, EPDCCH and EPDCCH superposition transmission, and the like.

The radio resource control unit 1011 generates or acquires downlink data (transport block), system information, RRC message, MAC CE, and the like arranged on the downlink PDSCH from the upper node. The radio resource control unit 1011 outputs downlink data to the transmission unit 103 and outputs other information to the control unit 102. The radio resource control unit 1011 manages various setting information of the terminal device 2. Note that some of the functions of the radio resource control unit may be performed in the MAC layer or the physical layer.

The radio resource control unit 1011 can set information related to carrier aggregation (for example, Scell addition / release, etc.). The radio resource control unit 1011 can set information on MBSFN subframes (for example, subframe allocation for MBSFN).

The radio resource control unit 1011 sets information (for example, MUST assist information) regarding MUST settings for each terminal device. The radio resource control unit 1011 sets a cell radio network temporary identifier (C-RNTI: “Cell” Radio “Network” Temporary “Identifier”) for each terminal apparatus. For example, C-RNTI is a terminal identifier in dynamic scheduling. C-RNTI is used for encryption (scrambling) of PDCCH and PDSCH in dynamic scheduling. The radio resource control unit 1011 sets a semi-persistent cell radio network temporary identifier (SPS C-RNTI: Semi-Persistent Scheduling Cell Radio Network Temporary Identifier) for each terminal device. SPS C-RNTI is a terminal identifier in semi-persistent scheduling. SPS C-RNTI is used for encryption (scrambling) of PDCCH and PDSCH in semi-persistent scheduling.

The radio resource control unit 1011 can set information related to SPS for each terminal device. The SPS configuration can be included in individual radio resource configuration parameters (for example, RadioResourceConfigDedicated in LTE-A). For the SPS setting, a parameter SPS-Config in LTE-A can be used. The SPS configuration includes parameters indicating SPS C-RNTI configuration, downlink / uplink SPS setup, and release. The SPS setting includes a parameter indicating a semi-persistent scheduling interval in the downlink / uplink. The SPS setting includes a parameter indicating the number of HARQ processes in semi-persistent scheduling. The radio resource control unit 1011 may be configured not to perform SPS setting when the MUST assist information is set. The radio resource control unit 1011 may not be able to set MUST assist information when the SPS setting is performed. The radio resource control unit 1011 performs control so that a terminal device for which carrier aggregation is set (for example, when Scell is set) / a terminal device for which carrier aggregation is activated cannot apply MUST. You can also. The radio resource control unit 1011 can also perform control so that a terminal device that has activated carrier aggregation cannot apply MUST. The radio resource control unit 1011 can also perform control so that the MUST cannot be applied to the terminal apparatus in which the MBSFN subframe / MBSFN subframe is set.

The scheduling unit 1012 determines a frequency and a time resource (subcarrier and subframe) to allocate a physical channel (PDSCH and PUSCH) to be transmitted to each terminal device. The scheduling unit 1012 allocates frequency and time resources in consideration of whether each terminal apparatus supports MUST. The scheduling unit 1012 allocates frequency and time resources in consideration of the scheduling method (DS / SPS) of each terminal device. When MUST is performed between the terminal device 2A and the terminal device 2B, the scheduling unit 1012 allocates downlink data of both terminal devices to overlapping frequency and time resources (resource blocks). In this case, the scheduling unit 1012 preferably uses the same frequency and time resources for both terminal apparatuses. Scheduling section 1012 allocates the downlink data of both terminal apparatuses to different frequency and time resources when MUST is not performed between terminal apparatus 2A and terminal apparatus 2B (when performing orthogonal multiple access (OMA: Orthogonal Multiple Access)). The scheduling unit 1012 takes into account the setting regarding the MUST of the radio resource control unit 1011 (including the collaboration of the setting of the MUST and the setting of other functions) and the setting regarding the SPS, and uses the MUST or OMA to generate resources for the downlink data. Can also be assigned.

The scheduling unit 1012 determines the coding rate, modulation scheme (or MCS), transmission power, and the like of the physical channels (PDSCH and PUSCH). The scheduling unit 1012 outputs the determined information to the control unit 102. The scheduling unit 1012 generates information used for scheduling of physical channels (PDSCH and PUSCH) based on the scheduling result. The scheduling unit 1012 outputs the generated information to the control unit 102.

The control unit 102 generates a control signal for controlling the transmission unit 103 and the reception unit 104 based on the information input from the higher layer processing unit 101. The control unit 102 generates downlink control information based on the information input from the higher layer processing unit 101 and outputs the downlink control information to the transmission unit 103. The downlink control information includes a PDSCH / PUSCH resource allocation field, a HARQ process number field, and a new data indicator (NDI: “New” Date “Indicator) field. The control unit 102 can include information indicating that the MUST is applied to the channel transmitted in the PDSCH / PUSCH resource allocation field in the downlink control signal.

The control unit 102 can set activation / release of SPS using the downlink control information. For example, using a combination of TPC command field for uplink channel / cyclic shift field for demodulation reference signal / field for MCS / HARQ process number field / field for redundancy / fold for resource allocation, etc. SPS activation / cancellation can be set.

CRC (Cyclic Redundancy Check) is generated for the generated DCI format data series. In the case of DS, the generated CRC is encrypted (scrambling) by C-RNTI (Cell-RadioorNetwork Temporary Identifier). In the case of SPS, the generated CRC is encrypted by SPS C-RNTI. The encrypted CRC is added to the DCI format. The signal generated as the DCI format is arranged on the PDCCH.

In DS, the terminal apparatus determines whether transmission corresponding to the allocated resource is new or retransmission based on the HARQ process ID and the NDI field included in the PDCCH. If the NDI value is different from the previous NDI value in the same HARQ process, it is judged as new, and if it is the same as the previous NDI value in the same HARQ process, it is judged as retransmission.

* The definition of SDI NDI is different. The value of NDI indicates the function of PDCCH signaling transmitted to the SPS C-RNTI. If the received NDI value is 0, the PDCCH signaling assigned to the SPS C-RNTI is for activation or modification of the SPS transmission resource. If the received NDI value is 1, the SPS C -PDCCH signaling allocated for RNTI allocates transmission resources to the terminal device for SPS retransmission.

The transmission unit 103 generates a downlink reference signal according to the control signal input from the control unit 102. The transmitting unit 103 encodes and modulates the HARQ indicator, the downlink control information, and the downlink data input from the higher layer processing unit 101 for each terminal apparatus, and generates PHICH, PDCCH, EPDCCH, and PDSCH. The transmission unit 103 multiplexes PHICH, PDCCH, EPDCCH, PDSCH, and a downlink reference signal, and transmits a signal to the terminal apparatus 2 via the transmission antenna 105.

The encoding unit 1031 is configured to block the HARQ indicator, the downlink control information, and the downlink data input from the higher layer processing unit 101 using a predetermined encoding method determined by the radio resource control unit 1011. Encoding, convolutional encoding, turbo encoding, etc. are performed. The modulation unit 1032 converts the coded bits input from the coding unit 1031 into predetermined BPSK (Binary Phase Shift Keying), QPSK (quadrature Phase Shift Keying), 16 QAM (quadrature Amplitude Modulation), 64 QAM, 256 QAM, etc. Modulation is performed by the modulation scheme determined by the radio resource control unit 1011.

The downlink reference signal generation unit 1033 generates a sequence known by the terminal device 2 as a downlink reference signal. The known sequence is determined by a predetermined rule based on a physical cell identifier (PCI, cell ID) for identifying the base station apparatus 1A.

The multiplexing unit 1034 multiplexes the modulated modulation symbol of each channel, the generated downlink reference signal, and downlink control information. That is, multiplexing section 1034 arranges the modulated modulation symbol of each channel, the generated downlink reference signal, and downlink control information in the resource element.

The radio transmission unit 1035 generates an OFDM symbol by performing inverse fast Fourier transform (Inverse Fourier Transform: IFFT) on the multiplexed modulation symbols and the like. The radio transmission unit 1035 generates a baseband digital signal by adding a cyclic prefix (CP) to the OFDM symbol. Further, the wireless transmission unit 1035 converts the digital signal into an analog signal, removes excess frequency components by filtering, up-converts the carrier signal to a carrier frequency, amplifies the power, and outputs to the transmission antenna 105 for transmission.

The receiving unit 104 separates, demodulates and decodes the received signal received from the terminal device 2 via the receiving antenna 106-1 according to the control signal input from the control unit 102, and sends the decoded information to the upper layer processing unit 101. Output.

The radio reception unit 1041 converts an uplink signal received via the reception antenna 106-1 into a baseband signal by down-conversion, removes unnecessary frequency components, and maintains the signal level appropriately. The amplification level is controlled to perform quadrature demodulation based on the in-phase and quadrature components of the received signal, and the quadrature demodulated analog signal is converted into a digital signal. Radio receiving section 1041 removes a portion corresponding to CP from the converted digital signal. Radio receiving section 1041 performs fast Fourier transform (FFT) on the signal from which CP has been removed, extracts a signal in the frequency domain, and outputs the signal to demultiplexing section 1042.

The demultiplexing unit 1042 demultiplexes the signal input from the wireless reception unit 1041 into signals such as PUCCH, PUSCH, and uplink reference signal. This separation is performed based on radio resource allocation information included in the uplink grant that is determined in advance by the radio resource control unit 1011 by the base station apparatus 1A and notified to each terminal apparatus 2. Demultiplexing section 1042 compensates for the propagation paths of PUCCH and PUSCH. Further, the demultiplexing unit 1042 demultiplexes the uplink reference signal.

The demodulator 1043 obtains an inverse discrete Fourier transform (Inverse Fourier Transform: FTIDFT) modulation symbol from the PUSCH. The demodulation unit 1043 is configured to determine in advance modulation schemes such as BPSK, QPSK, 16QAM, 64QAM, 256QAM, or the like that the own device has previously notified each of the terminal devices 2 with an uplink grant for each of the modulation symbols of PUCCH and PUSCH. Is used to demodulate the received signal.

The decoding unit 1044 uses the coding rate of the demodulated PUCCH and PUSCH in a predetermined encoding method, the predetermined coding method, or the coding rate notified by the own device to the terminal device 2 using the uplink grant. Decoding is performed, and the decoded uplink data and uplink control information are output to the upper layer processing section 101. When PUSCH is retransmitted, decoding section 1044 performs decoding using the coded bits held in the HARQ buffer input from higher layer processing section 101 and the demodulated coded bits.

FIG. 4 is a schematic block diagram showing the configuration of the terminal device 2 according to the present embodiment. The terminal device 2 includes an upper layer processing unit (upper layer processing step) 201, a control unit (control step) 202, a transmission unit (transmission step) 203, a reception unit (reception step) 204, a channel state information generation unit (channel state information). Generation step) 205, a transmission antenna 206, and a reception antenna 207. The upper layer processing unit 201 includes a radio resource control unit (radio resource control step) 2011 and a scheduling information interpretation unit (scheduling information interpretation step) 2012. The transmission unit 203 includes an encoding unit (encoding step) 2031, a modulation unit (modulation step) 2032, an uplink reference signal generation unit (uplink reference signal generation step) 2033, a multiplexing unit (multiplexing step) 2034, and a radio transmission unit (Wireless transmission step) 2035 is included. The reception unit 204 includes a wireless reception unit (wireless reception step) 2041, a demultiplexing unit (demultiplexing step) 2042, and a signal detection unit (signal detection step) 2043.

The upper layer processing unit 201 outputs uplink data (transport block) generated by a user operation or the like to the transmission unit 203. The upper layer processing unit 201 includes a medium access control (Medium Access Control: MAC) layer, a packet data integration protocol (Packet Data Convergence Protocol: PDCP) layer, a radio link control (Radio Link Control: RLC) layer, a radio resource control (Radio) Resource (Control: RRC) layer processing.

The upper layer processing unit 201 outputs information indicating the function of the terminal device supported by the own terminal device to the transmission unit 203. For example, the information indicating the function of the terminal device supported by the terminal device includes information indicating support of MUST, information indicating support of SPS, information indicating support of carrier aggregation, and the like. When there are a plurality of functions corresponding to MUST, the upper layer processing unit 201 can transmit information indicating whether to support each function. When there are a plurality of functions corresponding to the SPS, the upper layer processing unit 201 can transmit information indicating whether to support each function.

The radio resource control unit 2011 manages various setting information of the own terminal device. The radio resource control unit 2011 generates information arranged in each uplink channel and outputs the information to the transmission unit 203. For example, the radio resource control unit 2011 signals information indicating the function of the terminal device supported by the terminal device in the RRC layer. The radio resource control unit 2011 acquires setting information related to CSI feedback transmitted from the base station apparatus and outputs the setting information to the control unit 202.

The radio resource control unit 2011 acquires SPS setting information from the reception unit 204. The radio resource control unit 2011 acquires information (MUST assist information) about the terminal device that causes interference from the reception unit 204. The radio resource control unit 2011 may acquire the MUST assist information when transmitting information indicating that MUST is supported to the base station apparatus 1A. The radio resource control unit 2011 may acquire the MUST assist information when receiving information indicating that MUST is supported from the base station apparatus 1A. The SPS setting information and MUST assist information are input to the control unit 202.

The scheduling information interpretation unit 2012 interprets downlink control information (DCI) received via the reception unit 204 and determines scheduling information. The scheduling information interpretation unit 2012 generates control information for controlling the reception unit 204 and the transmission unit 203 based on the scheduling information, and outputs the control information to the control unit 202.

The control unit 202 generates a control signal for controlling the receiving unit 204, the channel state information generating unit 205, and the transmitting unit 203 based on the information input from the higher layer processing unit 201. The control unit 202 controls the reception unit 204 and the transmission unit 203 by outputting the generated control signal to the reception unit 204, the channel state information generation unit 205, and the transmission unit 203.

The control unit 202 controls the transmission unit 203 to transmit the CSI generated by the channel state information generation unit 205 to the base station apparatus. The control unit 202 generates uplink control information (UCI) based on the information input from the higher layer processing unit 201 and outputs the uplink control information (UCI) to the transmission unit 203. In the UCI format, a format dedicated to a terminal device performing MUST may be defined.

The receiving unit 204 separates, demodulates, and decodes the received signal received from the base station apparatus 1A via the receiving antenna 207 according to the control signal input from the control unit 202, and sends the decoded information to the higher layer processing unit 201. Output. The receiving unit 204 performs signal detection in consideration of the MUST assist information. Furthermore, the receiving unit 204 can detect parameters necessary for removing or suppressing the interference signal by blind detection.

The radio reception unit 2041 converts a downlink signal received via the reception antenna 207 into a baseband signal by down-conversion, removes unnecessary frequency components, and amplifies the signal level so that the signal level is appropriately maintained. , And quadrature demodulation based on the in-phase and quadrature components of the received signal, and converting the quadrature demodulated analog signal into a digital signal. Radio receiving section 2041 removes a portion corresponding to CP from the converted digital signal, performs fast Fourier transform on the signal from which CP is removed, and extracts a frequency domain signal.

The demultiplexing unit 2042 separates the extracted signals into PHICH, PDCCH, EPDCCH, PDSCH, and downlink reference signals. The demultiplexing unit 2042 performs channel compensation for PHICH, PDCCH, and EPDCCH based on channel estimation values obtained from channel measurement using the downlink reference signal, detects downlink control information, and controls the control unit 202. Output to. Control unit 202 outputs the PDSCH and channel estimation value to signal detection unit 2043.

The signal detection unit 2043 detects a signal using the PDSCH and the channel estimation value, and outputs the signal to the higher layer processing unit 201. The terminal apparatus 2A that supports MUST has a function of removing or suppressing an interference signal in the signal detection unit 2043. The signal detection unit 2043 of the terminal device 2A demodulates and decodes PDSCH1 after removing or suppressing PDSCH2 that causes interference. The terminal device 2B demodulates and decodes PDSCH2. The terminal device 2B that supports MUST may be provided with a function of removing or suppressing the interference signal in the signal detection unit 2043.

The transmission unit 203 generates an uplink reference signal according to the control signal input from the control unit 202. The transmission unit 203 encodes and modulates the uplink data (transport block) and the uplink control signal input from the higher layer processing unit 201 to generate PUCCH and PUSCH. The PUSCH is encrypted (scrambled) using C-RNTI and SPS C-RNTI according to DS and SPS. Transmitting section 203 multiplexes PUCCH, PUSCH and the generated uplink reference signal, and transmits them to base station apparatus 1A via transmitting antenna 206.

The encoding unit 2031 performs encoding such as convolutional encoding and block encoding on the uplink control information input from the higher layer processing unit 201. The encoding unit 2031 performs turbo encoding encoding of the PUSCH based on information used for scheduling.

The modulation unit 2032 modulates the coded bits input from the coding unit 2031 using a modulation scheme notified by downlink control information such as BPSK, QPSK, 16QAM, 64QAM, or a modulation scheme predetermined for each channel. .

The uplink reference signal generation unit 2033 has a physical cell identifier (physical cell identity: referred to as PCI, Cell ID, etc.) for identifying the base station apparatus 1A, a bandwidth for arranging an uplink reference signal, and an uplink grant. A sequence determined by a predetermined rule (formula) is generated on the basis of the cyclic shift and the parameter value for generating the DMRS sequence notified in (1).

The multiplexing unit 2034 rearranges the PUSCH modulation symbols in parallel according to the control signal input from the control unit 202, and then performs a discrete Fourier transform (DFT). The multiplexing unit 2034 multiplexes the PUCCH and PUSCH signals and the uplink reference signal for each transmission antenna port. That is, multiplexing section 2034 arranges the PUCCH and PUSCH signals and the uplink reference signal in the resource element for each transmission antenna port.

The radio transmission unit 2035 performs inverse fast Fourier transform (Inverse Fourier Transform: IFFT) on the multiplexed signal, performs SC-FDMA modulation, and generates an SC-FDMA symbol. The radio transmission unit 2035 adds a CP to the SC-FDMA symbol to generate a baseband digital signal. Further, the radio transmission unit 2035 converts the baseband digital signal into an analog signal, removes an extra frequency component, converts it into a carrier frequency by up-conversion, amplifies the power, and transmits a base station via the transmission antenna 206. Transmit to device 1A.

FIG. 5 is a diagram illustrating an example of a flowchart in which the base station apparatus according to the present embodiment performs multiuser superimposed transmission. The base station device 1A receives the UE capability from the terminal devices 2A and 2B (S101). From the UE capability, the base station device 1A grasps whether the terminal devices 2A and 2B support MUST or SPS. The UE capability can include a function corresponding to a plurality of MUSTs. The base station apparatus 1A transmits various setting information related to radio resources to the terminal apparatuses 2A and 2B using RRC signaling or the like (S102). The base station apparatus 1A notifies the C-RNTI assigned to each terminal apparatus as setting information. 1 A of base station apparatuses notify MUST assist information with respect to the terminal device which supports MUST. 1 A of base station apparatuses notify SPS setting information with respect to the terminal device which supports SPS. The SPS setting information includes SPS C-RNTI.

When the downlink data to be transmitted to the terminal devices 2A and 2B is generated (S103), the base station device 1A determines whether the terminal device 2A corresponding to the Near-UE supports SPS (S104). The determination is made based on the SPS support information received from the terminal device 2A. In S104, the base station apparatus 1A can also determine whether or not information related to SPS support has been received from the terminal apparatus 2A. In S104, the base station apparatus 1A may make a determination based on the SPS setup / release setting included in the SPS setting information addressed to the terminal apparatus 2A. The base station apparatus 1A may make a determination based on the setting of SPS activation / release indicated by the downlink control information addressed to the terminal apparatus 2A.

When it is determined that the terminal device 2A supports SPS (YES in S104), the base station device 1A transmits downlink data to the terminal devices 2A and 2B using orthogonal multiple access (OMA) (S105). ). In this case, the base station apparatus 1A transmits downlink data to the terminal apparatuses 2A and 2B without using non-orthogonal multiple access (MUST). The base station apparatus 1A scrambles the downlink data to be transmitted to the terminal apparatus 2A / terminal apparatus 2B with SPS C-RNTI / C-RNTI according to the required quality (QoS, voice data, etc.) of the downlink data. To do. In addition, the base station apparatus can also consider the information regarding MUST / information regarding SPS set in the radio | wireless resource part 1011 in S104. For example, when the base station apparatus receives information indicating that MUST supporting SPS is supported from the terminal apparatus, the base station apparatus selects to transmit downlink data to the terminal apparatus using MUST. You can also.

The terminal device 2 receives downlink data (interference removal or suppression, demodulation, decoding processing, etc.) based on the radio resource information received from the base station device 1A and the downlink control information. The terminal device 2A that supports SPS performs reception processing assuming that the received downlink data is transmitted by OMA (not multiplexed by MUST). The terminal apparatus 2A that supports MUST may perform reception processing on the assumption that downlink data is transmitted using DS (a downlink is transmitted without using SPS).

If it is determined in S104 that the terminal apparatus 2A does not support SPS (NO in S104), the base station apparatus 1A transmits downlink data to the terminal apparatuses 2A and 2B using MUST or OMA (S106). ). The downlink data transmitted to the terminal device 2A is scrambled by the C-RNTI assigned to the terminal device. The downlink data transmitted to the terminal device 2B is scrambled by the C-RNTI / SPS C-RNTI assigned to the terminal device according to the required quality of the downlink data.

FIG. 6 is a diagram illustrating another example of a flowchart in which the base station apparatus according to the present embodiment performs multi-user superimposed transmission. S201 to S203 are the same processes as S101 to S103 in FIG. When downlink data to be transmitted to the terminal devices 2A and 2B is generated (S203), the base station device 1A determines whether the terminal device 2A / terminal device 2B supports MUST (S204). In S204, the base station apparatus 1A may make a determination based on the setup / release setting included in the MUST setting information addressed to the terminal apparatus.

In S204, when there is a terminal device supporting MUST, the base station device 1A transmits downlink data using DS to the terminal device supporting MUST (S205). The base station apparatus 1A transmits downlink data to a terminal apparatus that supports MUST without using SPS.

The terminal device 2 receives downlink data (interference removal or suppression, demodulation, decoding processing, etc.) based on the radio resource information received from the base station device 1A and the downlink control information. The terminal device 2A that supports SPS performs reception processing assuming that the received downlink data is transmitted by OMA (not multiplexed by MUST). The terminal apparatus 2A that supports MUST may perform reception processing on the assumption that downlink data is transmitted using DS (a downlink is transmitted without using SPS).

In S204, if at least one of the terminal device 2A and the terminal device 2B supports MUST, the base station device 1A uses the dynamic scheduling (DS) to determine the terminal device 2A / terminal. You may make it transmit downlink data to the apparatus 2B. In this case, the downlink data transmitted to the terminal device 2A and the terminal device 2B is scrambled by C-RNTI.

If it is determined in S204 that the terminal device does not support MUST, the base station device 1A transmits downlink data to the terminal device 2A / terminal device 2B using DS or SPS without using MUST. (S206). For example, the base station apparatus 1A transmits downlink data by OMA using DS or SPS. Note that the base station apparatus can also consider the information on MUST / information on SPS set in the radio resource unit 1011 in S204. For example, when the base station apparatus receives information indicating that MUST supporting SPS is supported from the terminal apparatus, the base station apparatus selects to transmit downlink data to the terminal apparatus using MUST. You can also.

FIG. 7 is a diagram illustrating another example of a flowchart in which the base station apparatus according to the present embodiment performs multi-user superimposed transmission. The base station device 1A receives the UE capability from the terminal devices 2A and 2B (S301). From the UE capability, the base station device 1A grasps whether the terminal devices 2A and 2B support MUST or SPS. The UE capability can include a function corresponding to a plurality of MUSTs. The base station apparatus 1A transmits various setting information to the terminal apparatuses 2A and 2B using RRC signaling or the like (S302). The base station apparatus 1A notifies each terminal apparatus of C-RNTI as setting information. 1 A of base station apparatuses notify MUST assist information with respect to the terminal device which supports MUST. 1 A of base station apparatuses notify SPS setting information with respect to the terminal device which supports SPS. The SPS setting information includes SPS C-RNTI.

The base station apparatus 1A will be described in the case where information indicating that MUST is supported is received from the terminal apparatus 2A. When downlink data to be transmitted to the terminal devices 2A and 2B is generated (S303), the base station device 1A determines whether the terminal device 2A corresponding to the Near-UE transmits the downlink data using SPS. Is determined (S304). For example, when the downlink data addressed to the terminal device 2A is voice data, the base station device 1A determines to transmit the downlink data using SPS.

When it is determined that the downlink data is transmitted to the terminal device 2A using SPS, the base station device 1A transmits the downlink data to the terminal devices 2A and 2B using OMA (S305). The base station apparatus 1A transmits downlink data to the terminal apparatuses 2A and 2B without using MUST. The base station apparatus 1A transmits downlink data scrambled by the SPS C-RNTI to the terminal apparatus 2A. The base station apparatus 1A scrambles the downlink data to be transmitted to the terminal apparatus 2B using the SPS C-RNTI / C-RNTI according to the required quality of the downlink data.

The terminal device 2 receives downlink data (interference removal or suppression, demodulation, decoding processing, etc.) based on the radio resource information received from the base station device 1A and the downlink control information. When receiving downlink data by SPS (when descrambling by SPS C-RNTI), the terminal device 2A assumes that the downlink data is transmitted by OMA (not multiplexed by MUST), and is received. Perform processing. When the downlink data is received by MUST, the terminal apparatus 2A performs reception processing on the assumption that the downlink data is transmitted using the DS (the downlink is transmitted without using the SPS). May be.

In S304, when it is determined that downlink data is transmitted to the terminal device 2A without using SPS (for example, when it is determined that downlink data is transmitted using DS), the base station device 1A receives the terminal devices 2A and 2B. In addition, downlink data transmission using MUST can be selected (S306). When the base station apparatus 1A transmits downlink data using MUST, the base station apparatus 1A transmits downlink data scrambled by C-RNTI to the terminal apparatus 2A. The base station apparatus 1A scrambles the downlink data to be transmitted to the terminal apparatus 2B using the SPS C-RNTI / C-RNTI according to the quality of the downlink data. Note that the base station apparatus can also consider the information on MUST / information on SPS set in the radio resource unit 1011 in S304. For example, when the base station apparatus receives information indicating that MUST supporting SPS is supported from the terminal apparatus, the base station apparatus selects to transmit downlink data to the terminal apparatus using MUST. You can also.

FIG. 8 is a diagram illustrating another example of a flowchart in which the base station apparatus according to the present embodiment performs multi-user superimposed transmission. S401 to S403 are the same processes as S301 to S303 in FIG.

The base station apparatus 1A will be described in the case where information indicating that MUST is supported is received from the terminal apparatus 2A. When downlink data to be transmitted to the terminal devices 2A and 2B is generated (S403), the base station device 1A determines whether to transmit the downlink data using MUST (S404). When transmitting downlink data of the terminal apparatuses 2A and 2B using MUST, the base station apparatus 1A transmits downlink data to the terminal apparatus 2A using DS (S405). The base station apparatus 1A transmits downlink data scrambled by C-RNTI to the terminal apparatus 2A. The base station apparatus 1A scrambles the downlink data to be transmitted to the terminal apparatus 2B using the SPS C-RNTI / C-RNTI according to the required quality of the downlink data.

The terminal device 2 receives downlink data (interference removal or suppression, demodulation, decoding processing, etc.) based on the radio resource information received from the base station device 1A and the downlink control information. When receiving downlink data with SPS (when descrambled with SPS C-RNTI), the terminal device 2A assumes that the downlink data is transmitted with OMA (it is assumed that it has not been multiplexed with MUST, and reception processing) When the downlink data is received by MUST, the terminal apparatus 2A receives the data by assuming that the downlink data is transmitted using the DS (the downlink is transmitted without using the SPS). Processing may be performed.

When transmitting downlink data without using MUST in S404, the base station apparatus 1A transmits downlink data to the terminal apparatuses 2A and 2B using DS or SPS according to the request for the quality of the downlink data. (S406). Note that the base station apparatus can also consider the information on MUST / information on SPS set in the radio resource unit 1011 in S404. For example, when the base station apparatus receives information indicating that MUST supporting SPS is supported from the terminal apparatus, the base station apparatus selects to transmit downlink data to the terminal apparatus using MUST. You can also.

In SPS, the base station apparatus transmits downlink data based on a semi-persistent scheduling interval without transmitting a downlink assignment (for example, PDCCH). The terminal apparatus receives downlink data without receiving a downlink assignment based on the semi-persistent scheduling interval. In this embodiment, when transmitting data using SPS to at least Near-UE, the base station apparatus selects OMA and transmits downlink data (without using MUST, downlink data is transmitted). Send). Thereby, the communication system which has SPS which concerns on this embodiment can reduce the addition of the control signal accompanying MUST application, such as power allocation information. Also, since the communication system according to the present embodiment does not include the presence or absence of application of MUST in blind decoding in SPS, it is possible to suppress an increase in the load on the terminal device due to application of MUST.

(Second Embodiment)
FIG. 9 is a diagram illustrating an example of a flowchart in which the base station apparatus according to the present embodiment performs multiuser superimposed transmission. Each of the base station apparatus and the terminal apparatus according to the present embodiment has the same configuration as that shown in FIGS. Hereinafter, differences / additional points from the first embodiment will be mainly described.

In FIG. 9, the base station apparatus 1A receives the UE capability from the terminal apparatuses 2A and 2B (S501). From the UE capability, the base station device 1A grasps whether the terminal devices 2A and 2B support MUST or SPS. The UE capability can include a function corresponding to a plurality of MUSTs. The base station device 1A transmits various setting information to the terminal devices 2A and 2B using RRC signaling or the like (S502). The base station apparatus 1A notifies the C-RNTI assigned to each terminal apparatus as setting information. 1 A of base station apparatuses notify MUST assist information with respect to the terminal device which supports MUST. 1 A of base station apparatuses notify SPS setting information with respect to the terminal device which supports SPS. The SPS setting information includes SPS C-RNTI.

When downlink data to be transmitted to the terminal devices 2A and 2B is generated (S503), the base station device 1A determines whether the terminal device 2A corresponding to Near-UE is transmitting the downlink data using SPS. (S504). In S504, when it is determined that downlink data is transmitted without using SPS (for example, when downlink data is transmitted using DS), base station apparatus 1A uses MUST or OMA to make terminal apparatuses 2A and 2B. The downlink data is transmitted to (S507).

When it is determined in S504 that downlink data is transmitted using SPS, the terminal device 2B corresponding to the Far-UE determines whether or not downlink data is transmitted using SPS (S505). If it is determined in S505 that downlink data is transmitted using SPS, the base station apparatus 1A transmits downlink data to the terminal apparatuses 2A and 2B using MUST or OMA (S507). The terminal device 2 receives downlink data (interference removal or suppression, demodulation, decoding processing, etc.) based on the radio resource information received from the base station device 1A and the downlink control information.

In S505, when it is determined that downlink data is transmitted without using SPS (for example, when downlink data is transmitted using DS), base station apparatus 1A uses OMA to transmit to terminal apparatuses 2A and 2B. Link data is transmitted (S506). By the processing of FIG. 9, the base station apparatus 1A uses the MUST to transmit downlink data when the Near-UE transmits using DS or when both the Near-UE and Far-UE transmit using SPS. Can be transmitted. Note that the base station apparatus can also consider the information on MUST / information on SPS set in the radio resource unit 1011 in S504. For example, when the base station apparatus receives information indicating that MUST supporting SPS is supported from the terminal apparatus, the base station apparatus selects to transmit downlink data to the terminal apparatus using MUST. You can also.

FIG. 10 is a diagram illustrating another example of a flowchart in which the base station apparatus according to the present embodiment performs multi-user superimposed transmission. S601 to S603 are the same processes as S501 to S503 in FIG.

In FIG. 10, when downlink data to be transmitted to the terminal devices 2A and 2B is generated (S603), the base station device 1A transmits the downlink data using the SPS by the terminal device 2A corresponding to Near-UE. It is determined whether or not (S604). In S604, when it is determined that downlink data is transmitted without using SPS (for example, when downlink data is transmitted using DS), the base station apparatus 1A uses the MUST or OMA to transmit the terminal apparatuses 2A and 2B. The downlink data is transmitted to (S607).

When it is determined in S604 that downlink data is transmitted using SPS, the terminal apparatus 2B corresponding to the Far-UE determines whether or not downlink data is transmitted using SPS (S605). If it is determined in S605 that downlink data is to be transmitted without using SPS, the base station apparatus 1A transmits downlink data to the terminal apparatuses 2A and 2B using OMA (S608). The terminal device 2 receives downlink data (interference removal or suppression, demodulation, decoding processing, etc.) based on the radio resource information received from the base station device 1A and the downlink control information.

When it is determined in S605 that downlink data is transmitted using SPS, the base station apparatus 1A determines whether or not the SPS interval settings of the Near-UE and the Far-UE are the same (S606). For example, the base station device 1A compares the settings of the semiPersistSchedIntervalDL between the terminal device 2A and the terminal device 2B. When the setting of the SPS interval is the same, the base station apparatus 1A transmits downlink data to the terminal apparatuses 2A and 2B using MUST or OMA (S607). 1 A of base station apparatuses can also transmit the information which shows whether the said SPS interval is the same to a terminal device. On the other hand, when the SPS intervals are different, the base station apparatus 1A transmits downlink data to the terminal apparatuses 2A and 2B using OMA (S608). By the processing of FIG. 10, the base station apparatus 1A transmits downlink data using MUST when Near-UE transmits using DS or when the SPS interval of both Near-UE and Far-UE is the same. It becomes possible. Note that the base station apparatus can also consider the information on MUST / information on SPS set in the radio resource unit 1011 in S604. For example, when the base station apparatus receives information indicating that MUST supporting SPS is supported from the terminal apparatus, the base station apparatus selects to transmit downlink data to the terminal apparatus using MUST. You can also.

FIG. 11 is a diagram illustrating another example of a flowchart in which the base station apparatus according to the present embodiment performs multi-user superimposed transmission. S701 to S704 are the same processes as S701 to S704 in FIG.

In S705, when it is determined that downlink data is transmitted without using SPS, the base station apparatus 1A transmits downlink data to the terminal apparatuses 2A and 2B using OMA (S708). If it is determined in S705 that downlink data is transmitted using SPS, the base station apparatus 1A determines whether the SPS interval setting between Near-UE and Far-UE is n times or 1 / n (n is a natural number). Is determined (S706). When the setting of the SPS interval is n times or 1 / n (n is a natural number) (for example, in the base station device 1A, the SPS interval of the terminal device 2A is 10 subframes, and the SPS interval of the terminal device 2B is 20 subframes) ), The base station device 1A transmits downlink data to the terminal devices 2A and 2B using MUST or OMA (S707). The base station apparatus 1A can also transmit information indicating whether the SPS interval is n times or 1 / n to the terminal apparatus. 1 A of base station apparatuses can also transmit ratio of both SPS space | interval to a terminal device. The terminal device 2 receives downlink data (interference removal or suppression, demodulation, decoding processing, etc.) based on the radio resource information received from the base station device 1A and the downlink control information.

On the other hand, when the setting of the SPS interval is not n times or 1 / n (n is a natural number) (for example, in the base station apparatus 1A, the SPS interval of the terminal apparatus 2A is 10 subframes, and the SPS interval of the terminal apparatus 2B is 32 subframes) In the case of a frame), the base station apparatus 1A transmits downlink data to the terminal apparatuses 2A and 2B using OMA (S708). With the processing in FIG. 11, when the Near-UE transmits using DS, the base station apparatus 1A sets the SPS interval of both Near-UE and Far-UE to n times or 1 / n (n is a natural number) In this case, downlink data can be transmitted using MUST. Note that the base station apparatus can also consider the information on MUST / information on SPS set in the radio resource unit 1011 in S704. For example, when the base station apparatus receives information indicating that MUST supporting SPS is supported from the terminal apparatus, the base station apparatus selects to transmit downlink data to the terminal apparatus using MUST. You can also.

In this embodiment, when both Near-UE and Far-UE transmit data using SPS, the base station apparatus can select MUST and transmit downlink data. Thereby, the communication system which has SPS which concerns on this embodiment can reduce the addition of the control signal accompanying MUST application, such as power allocation information. Also, since the communication system according to the present embodiment does not include the presence or absence of application of MUST in blind decoding in SPS, it is possible to suppress an increase in the load on the terminal device due to application of MUST.

In the communication system according to the present embodiment, after determining that the Near-UE transmits data by SPS (S504 in FIG. 9, S604 in FIG. 10, S704 in FIG. 11), the base station apparatus 1A performs the SPS of the Near-UE. It may be determined whether or not is the first transmission. When the SPS of the Near-UE is the first transmission, the base station apparatus 1A transitions to the determination of whether or not the Far-UE transmits data by SPS (S505 in FIG. 9, S605 in FIG. 10, and FIG. S705). When the Near-UE SPS is retransmitted, the base station apparatus 1A transmits downlink data using OMA (S506 in FIG. 9, S608 in FIG. 10, and S708 in FIG. 11). Thereby, the communication system which has SPS which concerns on this embodiment can reduce the addition of the control signal accompanying MUST application, such as power allocation information. Also, since the communication system according to the present embodiment does not include the presence or absence of application of MUST in blind decoding in SPS, it is possible to suppress an increase in the load on the terminal device due to application of MUST.

In the communication system according to the present embodiment, after determining that the Near-UE transmits data by SPS (S504 in FIG. 9, S604 in FIG. 10, S704 in FIG. 11), the base station apparatus 1A downloads to the Near-UE. A determination as to whether to transmit a link control signal (for example, PDCCH) may be added. As SPS accompanying transmission of PDCCH, there are cases where SPS settings are modified or retransmitted. When the base station apparatus 1A is accompanied by transmission of PDCCH in the SPS, the base station apparatus 1A can also make a transition to the determination of whether or not the Far-UE transmits data in the SPS (S505 in FIG. 10 S605, FIG. 11 S705). When PDCCH transmission is not performed in SPS, base station apparatus 1A transmits downlink data using OMA (S506 in FIG. 9, S608 in FIG. 10, and S708 in FIG. 11). Thereby, the communication system which has SPS which concerns on this embodiment can reduce the addition of the control signal accompanying MUST application, such as power allocation information. Also, since the communication system according to the present embodiment does not include the presence or absence of application of MUST in blind decoding in SPS, it is possible to suppress an increase in the load on the terminal device due to application of MUST.

The base station apparatus can perform settings for applying different MUSTs in Pcell and Scell. For example, when the base station apparatus 1A sets MUST assist information in the terminal apparatus 1A in the Pcell, the base station apparatus 1A transmits downlink data using MUST / OMA in consideration of the settings related to SPS by the processes in FIGS. You can decide what to do. On the other hand, when the MUST assist information is set in the terminal device 1A in Scell, the base station device 1A can determine whether to transmit downlink data using MUST / OMA without considering the setting related to SPS. In this case, the MUST assist information in the PCell and the MUST assist information in the Scell may have different set parameters or different optional parameters. Depending on whether the MUST assist information is set in the PCell or the Scell, the interpretation of the field included in the DCI may be different.

The program that operates in the apparatus related to the present invention may be a program that controls the central processing unit (CPU) or the like to function the computer so as to realize the functions of the above-described embodiments related to the present invention. The program or information handled by the program is temporarily read into volatile memory such as Random Access Memory (RAM) during processing, or stored in non-volatile memory such as flash memory or Hard Disk Drive (HDD). In response, the CPU reads and corrects / writes.

In addition, you may make it implement | achieve a part of apparatus in embodiment mentioned above with a computer. In that case, a program for realizing the functions of the embodiments may be recorded on a computer-readable recording medium. You may implement | achieve by making a computer system read the program recorded on this recording medium, and executing it. The “computer system” here is a computer system built in the apparatus, and includes hardware such as an operating system and peripheral devices. The “computer-readable recording medium” may be any of a semiconductor recording medium, an optical recording medium, a magnetic recording medium, and the like.

“Computer-readable recording medium” means a program that dynamically holds a program for a short time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory inside a computer system serving as a server or a client may be included, which holds a program for a certain period of time. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

Also, each functional block or various features of the apparatus used in the above-described embodiments can be implemented or executed by an electric circuit, that is, typically an integrated circuit or a plurality of integrated circuits. Electrical circuits designed to perform the functions described herein can be general purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or other Programmable logic devices, discrete gate or transistor logic, discrete hardware components, or combinations thereof. A general purpose processor may be a microprocessor or a conventional processor, controller, microcontroller, or state machine. The electric circuit described above may be configured with a digital circuit or an analog circuit. In addition, when an integrated circuit technology appears to replace the current integrated circuit due to the advancement of semiconductor technology, an integrated circuit based on the technology can be used.

Note that the present invention is not limited to the above-described embodiment. In the embodiment, an example of the apparatus has been described. However, the present invention is not limited to this, and a stationary or non-movable electronic device installed indoors or outdoors, such as an AV device, a kitchen device, It can be applied to terminal devices or communication devices such as cleaning / washing equipment, 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.

The present invention is suitable for use in a base station device, a terminal device, and a communication method.

Note that this international application claims priority based on Japanese Patent Application No. 2016-070494 filed on March 31, 2016, and the entire contents of Japanese Patent Application No. 2016-070494 are incorporated herein by reference. Included in international applications.

1A Base station apparatus 2A, 2B Terminal apparatus 1-1 Range in which base station apparatus 1A can be connected to the terminal apparatus 101 Upper layer processing section 102 Control sections 103-1, 103-2 Transmitting section 104 Receiving sections 105-1, 105- 2 Transmitting antenna 106-1 Receiving antenna 1011 Radio resource control unit 1012 Scheduling unit 1031 Encoding unit 1032 Modulating unit 1033 Downlink reference signal generating unit 1034 Multiplexing unit 1035 Radio transmitting unit 1041 Radio receiving unit 1042 Demultiplexing unit 1043 Demodulating unit 1044 Decoding Unit 201 upper layer processing unit 202 control unit 203 transmission unit 204 reception unit 205 channel state information generation unit 206 transmission antenna 207 reception antenna 2011 radio resource control unit 2012 scheduling information interpretation unit 2031 encoding unit 2032 modulation unit 2033 uplink reference No. generator 2034 multiplexing section 2035 radio transmitting unit 2041 radio reception section 2042 demultiplexing unit 2043 signal detector

Claims (11)

1. A base station apparatus that communicates with a first terminal apparatus and a second terminal apparatus,
   A receiving unit that receives information indicating that multi-user superimposed transmission is supported from the first terminal device;
   A transmission unit for transmitting downlink data to the first terminal device and the second terminal device;
   The receiving unit receives information indicating that semi-persistent scheduling is supported from the first terminal device;
   When the transmission unit transmits the downlink by semi-persistent scheduling, the base station transmits downlink data to the first terminal device and the second terminal device using orthogonal multi-access. apparatus.
2. When the receiving unit has not received information indicating that semi-persistent scheduling is supported from the first terminal device, the receiving unit applies multi-user superimposed transmission, and the first terminal device and the second terminal The base station apparatus according to claim 1, wherein downlink data is transmitted to the apparatus.
3. When transmitting the downlink data to the first terminal device by dynamic scheduling, the transmission unit applies multiuser superposition transmission to transmit downlink data to the first terminal device and the second terminal device. The base station apparatus according to claim 1, wherein transmission is performed.
4. The transmitter is
   When transmitting downlink data to the second terminal apparatus using semi-per system scheduling, multi-user superimposed transmission is applied to transmit downlink data to the first terminal apparatus and the second terminal apparatus. The base station apparatus according to claim 3, wherein:
5. The transmitter is
   Transmitting downlink data to the second terminal device using semi-persistent scheduling, the semi-persistent scheduling interval for downlink data transmission of the first terminal device and the downlink of the first terminal device When the semi-persistent scheduling interval for link data transmission is the same, multi-user superimposed transmission is applied to transmit downlink data to the first terminal apparatus and the second terminal apparatus. Item 4. The base station apparatus according to Item 3.
6. The transmitter is
   Transmitting downlink data to the second terminal device using semi-persistent scheduling, and the semi-persistent scheduling interval for downlink data transmission of the first terminal device is the downlink of the first terminal device. When the semi-persistent scheduling interval for link data transmission is n times or 1 / n times (n is a natural number), multi-user superimposed transmission is applied to the first terminal device and the second terminal device. The base station apparatus according to claim 3, wherein downlink data is transmitted.
7. A communication method of a base station apparatus that communicates with a first terminal apparatus and a second terminal apparatus,
   A receiving step of receiving information indicating that multi-user superimposed transmission is supported from the first terminal device;
   A transmission step of transmitting downlink data to the first terminal device and the second terminal device;
   When information indicating that semi-persistent scheduling is supported is received from the first terminal apparatus and the downlink is transmitted by semi-persistent scheduling, the first terminal apparatus and the second terminal apparatus are connected using orthogonal multi-access. A base station apparatus, wherein downlink data is transmitted to two terminal apparatuses.
8. A terminal device that communicates with a base station device,
   A transmitter that transmits information indicating that multi-base superimposed transmission is supported to the base station device;
   A receiving unit for receiving downlink data from the base station device;
   When the transmission unit transmits information indicating that semi-persistent scheduling is supported to the base station apparatus, it is assumed that downlink data using semi-persistent scheduling uses orthogonal multi-access. Characteristic terminal device.
9. The said receiving part demodulates the said downlink data on the assumption that it uses orthogonal multi-access or multi-user superimposition transmission, when downlink control information is received. Terminal device.
10. The terminal apparatus according to claim 9, wherein the receiving section performs processing to remove or suppress interference when demodulating the downlink data on the assumption that multi-user superimposed transmission is used.
11. A communication method of a terminal device that communicates with a base station device,
    A transmission step of transmitting information indicating that multi-user superimposed transmission is supported to the base station device;
    Receiving a downlink data from the base station apparatus,
    A communication characterized in that, when information indicating that semi-persistent scheduling is supported is transmitted to the base station apparatus, it is assumed that downlink data using semi-persistent scheduling uses orthogonal multi-access. Method.

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