JP2019140436A - Communication device and communication method - Google Patents

Abstract

To stabilize communication quality by reducing the interference power to another communication device and realizing highly efficient beam forming in an acquired communication medium and improve the frequency utilization efficiency or throughput in a communication device equipped with a function to perform communication by using multiple beams.SOLUTION: A communication device that implements first carrier sense includes a reception unit that performs the first carrier sense and secures a wireless medium only for a predetermined period, and a transmission unit that transmits a frame by using a spatial transmission filter in the predetermined period, and in the predetermined period, when a frame is transmitted by using at least two spatial transmission filters, the reception unit implements the first career sense on the basis of two spatial reception filters associated with the two spatial transmission filters.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a communication device and a communication method.

With the aim of starting commercial services around 2020, research and development activities related to the fifth generation mobile radio communication system (5G system) are being actively conducted. Recently, the International Telecommunication Union Radio communications Sector (ITU-R), an international standardization organization, has issued a vision recommendation on the standard system of 5G systems (International mobile telecommunication-2020 and beyond: IMT-2020). Reported (
Non-patent document 1).

In order for a communication system to cope with a rapid increase in data traffic, securing frequency resources is an important issue. Therefore, in 5G, one of the targets is to realize ultra-high capacity communication using a higher frequency band than the frequency band (frequency band) used in LTE (Long term evolution).

  However, path loss becomes a problem in wireless communication using a high frequency band. In order to compensate for path loss, beam forming using a large number of antennas has become a promising technique (see Non-Patent Document 2). It is also considered that a plurality of antennas (antenna panels) set with independent beam forming are provided and path loss is compensated by appropriately switching the antennas.

  Further, it is expected to utilize the duality of the propagation path characteristics of the downlink (base station device → terminal device) and the uplink (terminal device → base station device). For example, the terminal apparatus can efficiently perform path loss compensation by beam forming by performing uplink signal transmission using beam forming used for downlink signal reception.

On the other hand, securing cellular resources is an important issue for cellular services to cope with the rapid increase in data traffic. The frequency band (frequency band) that has been assumed for cellular services so far is a so-called licensed band that is licensed from the country or region where the wireless service provider provides the service. The frequency band is limited.

Therefore, recently, the provision of a cellular service using a frequency band called an unlicensed band that does not require use permission from the country or region has been discussed. Even in 5G, it is expected that the carrier aggregation technology adopted from the LTE-A system can be applied to an unlicensed band to cope with a rapid increase in data traffic with high efficiency (see Non-Patent Document 3).

“IMT Vision-Framework and overall objectives of the future development of IMT for 2020 and beyond,” Recommendation ITU-R M.2083-0, Sept. 2015. E. G. Larsson, O. Edfors, F. Tufvesson, and T. L. Marzetta, “Massive MIMO for next generation wireless system,” IEEE Commun. Mag., Vol.52, no. 2, pp. 186-195, Feb. 2014. 3GPP RP-170205, “Study on NR-based Access to Unlicensed Spectrum,” March 2017.

  However, the unlicensed band will be shared with other wireless access systems. In particular, in transmission using a high frequency, although beam forming by a large number of antennas is essential for improving desired reception power, there is a problem that a strong interference signal due to beam forming is generated stochastically.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a communication apparatus having a function of performing communication using a plurality of beams by the plurality of beams in the acquired communication medium. A communication device capable of realizing high-efficiency beam forming while stabilizing the communication quality while reducing the interference power to other communication devices while using the communication device, and thus improving the frequency utilization efficiency or throughput It is to provide a communication method.

  A configuration of a communication device and a communication method according to one aspect of the present invention for solving the above-described problem is as follows.

  (1) That is, a communication apparatus according to an aspect of the present invention is a communication apparatus that performs a first carrier sense, and that performs the first carrier sense and secures a wireless medium only for a predetermined period. And a transmission unit that transmits a frame using a spatial transmission filter in the predetermined period, and when the frame is transmitted using at least two spatial transmission filters in the predetermined period, the reception The unit performs the first carrier sense based on two spatial reception filters associated with the two spatial transmission filters.

  (2) Moreover, the communication apparatus which concerns on 1 aspect of this invention is described in said (1), The said receiving part performs said 1st based on a 1st spatial reception filter among said two spatial reception filters. One carrier sense period includes a first random back-off period.

  (3) A communication device according to an aspect of the present invention is described in (2) above, wherein the reception unit is not the first spatial reception filter of the two spatial reception filters. The random back-off period included in the first carrier sense period performed based on the spatial reception filter is the same as the first random back-off period.

  (4) In addition, the communication device according to an aspect of the present invention is described in (1) above, and the reception unit is capable of performing a second carrier sense without considering the spatial reception filter, and the reception unit Performs the second carrier sense when the maximum transmission power of the transmission unit is less than a predetermined value, and performs the first carrier sense when the maximum transmission power is a predetermined value or more. .

  (5) Moreover, the communication apparatus which concerns on 1 aspect of this invention is described in said (4), The said receiving part is based on the said spatial transmission filter set to the signal which the said transmission part transmits in the said predetermined period. Then, a threshold value associated with the first carrier sense is set.

(6) Moreover, the communication apparatus which concerns on 1 aspect of this invention is described in said (4), The said transmission part transmits a downlink shared channel (PDSCH) and a synchronous signal block (SSB) in the said predetermined period. In this case, the reception unit sets different threshold values associated with the first carrier sense depending on whether QCL (Quasi-colocation) is set in the PDSCH and SSB. To do.

  (7) Moreover, the communication apparatus which concerns on 1 aspect of this invention is described in said (4), The said receiving part is said 1st carrier based on the number of SRI (Sounding reference signal resource indicator) acquired. Sets the threshold associated with the sense.

  (8) A communication method according to an aspect of the present invention is a communication method for a communication apparatus that performs a first carrier sense, which performs the first carrier sense and uses a wireless medium only for a predetermined period. And a second step of transmitting a frame using a spatial transmission filter in the predetermined period, wherein the second step includes at least two of the spaces in the predetermined period. When transmitting a frame using a transmission filter, the first step performs the first carrier sense based on two spatial reception filters associated with the two spatial transmission filters.

  According to the present invention, high-efficiency beamforming can be realized while reducing interference power to other communication apparatuses, communication quality can be stabilized, and frequency use efficiency or throughput can be improved.

It is a figure which shows the example of the communication system which concerns on this embodiment. It is a block diagram which shows the structural example of the base station apparatus which concerns on this embodiment It is a block diagram which shows the structural example of the terminal device which concerns on this embodiment It is a figure which shows the example of the communication system which concerns on this embodiment. It is a figure which shows the example of the communication system which concerns on this embodiment.

  The communication system in this embodiment includes a base station device (transmitting device, cell, transmission point, transmission antenna group, transmission antenna port group, component carrier, eNodeB, transmission point, transmission / reception point, transmission panel, access point) and terminal device ( Terminal, mobile terminal, reception point, reception terminal, reception device, reception antenna group, reception antenna port group, UE, reception point, reception panel, station). A base station device connected to a terminal device (establishing a radio link) is called a serving cell.

  The base station apparatus and the terminal apparatus in the present embodiment can communicate in a frequency band (license band) that requires a license and / or a frequency band (unlicensed band) that does not require a license.

  In the present 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 in this embodiment includes a base station device 1A and a terminal device 2A. The coverage 1-1 is a range (communication area) in which the base station device 1A can be connected to the terminal device. Base station apparatus 1A is also simply referred to as a base station apparatus. The terminal device 2A is also simply referred to as a terminal device.

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

The PUCCH is used for transmitting uplink control information (UPCI). Here, the uplink control information includes ACK (a positive acknowledgement) or NACK (a negative acknowledgement) (ACK / NACK) for downlink data (downlink transport block, DL-SCH).
)including. ACK / NACK for downlink data is also referred to as HARQ-ACK and HARQ feedback.

Further, the uplink control information includes channel state information (CSI) for the downlink. Further, the uplink control information includes a scheduling request (SR) used for requesting an uplink shared channel (UL-SCH) resource. The channel state information includes a rank indicator RI (Rank Indicator) that designates a suitable spatial multiplexing number, a precoding matrix indicator PMI (Precoding Matrix Indicator) that designates a suitable precoder, and a channel quality indicator CQI that designates a suitable transmission rate. (Channel Quality Indicator), CSI-RS (Reference Signal, reference signal, channel state information reference signal) indicating a suitable CSI-RS resource, resource index CRI (CSI-RS Resource Indicator), and the like are applicable.

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

  The CRI indicates a CSI-RS resource suitable for reception power / reception quality from a plurality of CSI-RS resources.

  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. A part or all of the CQI value, PMI value, RI value, and CRI value are also collectively referred to as a CSI value.

  PUSCH is used to transmit 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.

The PUSCH is used for transmitting an RRC message. The RRC message is information / processed in the Radio Resource Control (RRC) layer.
Signal. The PUSCH is used to transmit a MAC CE (Control Element). Here, the MAC CE is information / signal processed (transmitted) in a 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 may be used to indicate the power headroom level.

  The PRACH is used for transmitting a random access preamble.

  In uplink wireless communication, an uplink reference signal (UL RS) 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. Here, the uplink reference signal includes DMRS (Demodulation Reference Signal), SRS (Sounding Reference Signal), and PT-RS (Phase-Tracking reference signal).

  DMRS relates to transmission of PUSCH or PUCCH. For example, base station apparatus 1A uses DMRS to perform propagation channel correction for PUSCH or PUCCH. For example, the base station apparatus 1A uses SRS to measure the uplink channel state. The SRS is used for uplink observation (sounding). PT-RS is used to compensate for phase noise. The uplink DMRS is also referred to as uplink DMRS.

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

The PBCH is used to broadcast a master information block (Master Information Block: MIB, Broadcast Channel: BCH) commonly used in terminal apparatuses.
PCFICH is used to transmit information indicating a region (for example, the number of OFDM (Orthogonal Frequency Division Multiplexing) symbols) used for transmission of PDCCH. The MIB is also called minimum system information.

  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 called HARQ-ACK. The terminal device 2A notifies the received ACK / NACK to the upper 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 2A notifies the upper layer of ACK.

PDCCH and EPDCCH are used for transmitting downlink control information (Downlink Control Information: DCI). Here, for transmission of downlink control information,
A plurality of DCI formats are defined. 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 downlink DCI format includes information on PDSCH resource allocation, information on MCS (Modulation and Coding Scheme) for PDSCH, and downlink control information such as a TPC command for PUCCH. Here, the DCI format for the downlink is also referred to as a downlink grant (or downlink assignment).

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

  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).

  Also, 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).

Also, 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 the terminal apparatus feeds back to the 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 channel state information.

For example, the channel state information report can be used for configuration 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 channel state information irregularly.

For example, the channel state information report can be used for configuration indicating an uplink resource for reporting semi-persistent channel state information (semi-persistent CSI). Channel state information report is a semi-permanent mode setting to report channel state information (CSI report mode)
Can be used for.

  Also, the DCI format for 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.

  The PDSCH is used to transmit downlink data (downlink transport block, DL-SCH). The 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.

  The PDSCH is used for transmitting 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.

The PDSCH is used to transmit an RRC message. Here, 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 2A (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. The PDSCH is used for transmitting the MAC CE.

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

The 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 apparatus feeds back to the base station apparatus. For example, the channel state information report is periodically transmitted by the channel state information (Periodic
CSI) can be used for configuration indicating uplink resources to report. Channel state information report is a mode setting to periodically report channel state information (CSI report mode)
Can be used for.

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 (SS) and a 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 signals include a primary synchronization signal (Primary Synchronization Signal: PSS) and a secondary synchronization signal (Secondary Synchronization Signal: SSS).

The synchronization signal is used by the terminal apparatus to synchronize the downlink frequency domain and time domain. The synchronization signal is used to measure reception power, reception quality, or signal-to-interference and noise power ratio (SINR). The received power measured with the synchronization signal is SS-RSRP (Synchronization Signal-Reference Signal Received Power), the reception quality measured with the synchronization signal is SS-RSRQ (Reference Signal Received Quality), and the SINR measured with the synchronization signal is SS- Also called SINR. SS-RSRQ is a ratio of SS-RSRP and RSSI. RSSI (Received Signal Strength Indicator) is the total average received power in a certain observation period. In addition, the synchronization signal / downlink reference signal is used by the terminal device for channel propagation correction of the downlink physical channel. For example, the synchronization signal / downlink reference signal is used by the terminal device to calculate downlink channel state information.

Here, the downlink reference signal includes CRS (Cell-specific Reference Signal;
Cell specific reference signal), DMRS (Demodulation Reference Signal), N
ZP CSI-RS (Non-Zero Power Channel State Information-Reference Signal
), ZP CSI-RS (Zero Power Channel State Information-Reference Signal)
), PT-RS, and TRS (Tracking Reference Signal). The downlink DMRS is also referred to as downlink DMRS. In the following embodiments, the term “CSI-RS” includes NZP CSI-RS and / or ZP CSI-RS.

  The CRS is transmitted in the entire band of the subframe, and is used to demodulate PBCH / PDCCH / PHICH / PCFICH / PDSCH. DMRS is transmitted in a subframe and a band used for transmission of PDSCH / PBCH / PDCCH / EPDCCH related to DMRS, and is used to demodulate PDSCH / PBCH / PDCCH / EPDCCH related to DMRS.

The resource of NZP CSI-RS is set by the base station apparatus 1A. For example, the terminal device 2A performs signal measurement (channel measurement) using NZP CSI-RS. The NZP CSI-RS is used for beam scanning for searching for a suitable beam direction, beam recovery for recovery when reception power / reception quality in the beam direction deteriorates, and the like. The resource of ZP CSI-RS is set by the base station apparatus 1A. The base station device 1A
CSI-RS is transmitted with zero output. For example, the terminal device 2A measures interference in a resource to which ZP CSI-RS corresponds.

  CSI-RS is used for measurement of received power, reception quality, or SINR. The reception power measured by CSI-RS is also called CSI-RSRP, the reception quality measured by CSI-RS is called CSI-RSRQ, and the SINR measured by CSI-RS is also called CSI-SINR. CSI-RSRQ is a ratio of CSI-RSRP and RSSI.

MBSFN (Multimedia Broadcast multicast service Single Frequency Network)
The RS is transmitted in the entire band of the subframe used for PMCH transmission. MBSFN
RS is used to demodulate PMCH. PMCH is transmitted by 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 unit of a transport channel used in the MAC layer is also referred to as a 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.

In addition, a base station device can integrate and communicate with a plurality of component carriers (CCs) for wider band transmission with respect to terminal devices that support carrier aggregation (CA; Carrier Aggregation). . In the carrier aggregation, one primary cell (PCell; Primary Cell) and one or more secondary cells (SCell; Secondary Cell) are set as a set of serving cells.

In dual connectivity (DC), a master cell group (MCG) and a secondary cell group (SCG) are set as serving cell groups. The MCG is composed of a PCell and optionally one or a plurality of SCells. The SCG includes a primary SCell (PSCell) and optionally one or a plurality of SCells.

  The base station apparatus can communicate using a radio frame. The radio frame is composed of a plurality of subframes (subsections). When the frame length is expressed by time, for example, the radio frame length can be 10 milliseconds (ms) and the subframe length can be 1 ms. In this example, the radio frame is composed of 10 subframes.

  The slot is composed of 14 OFDM symbols. Since the OFDM symbol length can vary depending on the subcarrier interval, the slot length can also be replaced by the subcarrier interval. Minislots are composed of fewer OFDM symbols than slots. A slot / minislot can be a scheduling unit. The terminal apparatus can know slot-based scheduling / minislot-based scheduling from the position (arrangement) of the first downlink DMRS. In slot-based scheduling, the first downlink DMRS is arranged in the third or fourth symbol of the slot. In minislot-based scheduling, the first downlink DMRS is arranged in the first symbol of scheduled data (resource, PDSCH).

  A resource block is defined by 12 consecutive subcarriers. The resource element is defined by a frequency domain index (for example, a subcarrier index) and a time domain index (for example, an OFDM symbol index). Resource elements are classified as uplink resource elements, downlink elements, flexible resource elements, and reserved resource elements. In the reserved resource element, the terminal apparatus does not transmit an uplink signal and does not receive a downlink signal.

Multiple subcarrier spacings (SCS) are also supported. For example, the SCS is 15/30/60/120/240/480 kHz.

The base station apparatus / terminal apparatus can communicate in a license band or an unlicensed band. The base station apparatus / terminal apparatus has a license band of PCell, and can communicate with at least one SCell operating in the unlicensed band by carrier aggregation. In addition, the base station apparatus / terminal apparatus can communicate with dual connectivity in which the master cell group communicates with the license band and the secondary cell group communicates with the unlicensed band. Further, the base station apparatus / terminal apparatus can communicate only with the PCell in the unlicensed band. In addition, the base station apparatus / terminal apparatus can communicate with CA or DC using only the unlicensed band. Note that a license band becomes a PCell, and an unlicensed band cell (SCell, PSCell) is assisted and communicated with, for example, CA, DC, or the like is also referred to as LAA (Licensed-Assisted Access). In addition, the fact that the base station apparatus / terminal apparatus communicates only in the unlicensed band is referred to as unlicensed stand-alone access (ULSA).
access). In addition, the communication between the base station apparatus / terminal apparatus using only the license band is also referred to as license access (LA).

  FIG. 2 is a schematic block diagram showing the configuration of the base station apparatus in the present embodiment. As shown in FIG. 2, the base station apparatus includes an upper layer processing unit (upper layer processing step) 101, a control unit (control step) 102, a transmission unit (transmission step) 103, a reception unit (reception step) 104, and a transmission / reception antenna. Reference numeral 105 denotes a measurement unit (measurement step) 106. 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 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, a radio A 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 (MAC) layer, a 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. In addition, 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 on the terminal device such as the function (UE capability) of the terminal device from the terminal device. In other words, the terminal apparatus transmits its own function to the base station apparatus using an upper layer signal.

  In the following description, the information regarding the terminal device includes information indicating whether the terminal device supports a predetermined function, or information indicating that the terminal device has introduced the predetermined function and completed the test. In the following description, whether or not to support a predetermined function includes whether or not installation and testing for the predetermined function have been completed.

  For example, when a terminal device supports a predetermined function, the terminal device transmits information (parameter) 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. Information (parameter) indicating whether or not a predetermined function is supported may be notified using 1 or 1 bit.

  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.

  Scheduling section 1012 determines the frequency and subframe to which physical channels (PDSCH and PUSCH) are allocated, the coding rate and modulation scheme (or MCS) and transmission power of physical channels (PDSCH and PUSCH), and the like. The scheduling unit 1012 outputs the determined information to the control unit 102.

  The scheduling unit 1012 generates information used for scheduling 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 transmission unit 103 generates a downlink reference signal according to the control signal input from the control unit 102, and encodes the HARQ indicator, downlink control information, and downlink data input from the higher layer processing unit 101. Then, PHICH, PDCCH, EPDCCH, PDSCH, and downlink reference signal are multiplexed, and a signal is transmitted to the terminal device 2A via the transmission / reception antenna 105.

The encoding unit 1031 performs block encoding, convolutional encoding, turbo encoding, LDPC (low density parity check: Low density) on the HARQ indicator, downlink control information, and downlink data input from the higher layer processing unit 101. Encoding is performed using a predetermined encoding method such as (parity check) encoding, Polar encoding, or the encoding method determined by the radio resource control unit 1011 is used. The modulation unit 1032 converts the encoded bits input from the encoding unit 1031 into BPSK (Binary Phase Shift Keying),
Modulation is performed by a predetermined modulation method such as QPSK (quadrature phase shift keying), 16QAM (quadrature amplitude modulation), 64QAM, or 256QAM, or determined by the radio resource control unit 1011.

  The downlink reference signal generation unit 1033 refers to a known sequence that the terminal device 2A obtains according to a predetermined rule based on a physical cell identifier (PCI, cell ID) for identifying the base station device 1A. Generate as a signal.

  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 wireless transmission unit 1035 generates an OFDM symbol by performing inverse fast Fourier transform (IFFT) on the multiplexed modulation symbol and the like, and adds a cyclic prefix (CP) to the OFDM symbol. A band digital signal is generated, the baseband digital signal is converted into an analog signal, an extra frequency component is removed by filtering, the signal is up-converted to a carrier frequency, power amplified, and output to the transmission / reception antenna 105 for transmission. . The transmission power at this time is based on information set via the control unit 102.

  The receiving unit 104 separates, demodulates, and decodes the received signal received from the terminal device 2A via the transmission / reception antenna 105 in accordance with the control signal input from the control unit 102, and outputs the decoded information to the upper layer processing unit 101. . The receiving unit 104 also has a function (step) for performing carrier sense.

The radio reception unit 1041 converts an uplink signal received via the transmission / reception antenna 105 into a baseband signal by down-conversion, removes unnecessary frequency components, and amplifies the signal level so that the signal level is properly maintained. The level is controlled, quadrature demodulation is performed based on the in-phase component and the quadrature component of the received signal, and the analog signal that has been demodulated 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 frequency domain signal, and outputs the signal to demultiplexing section 1042.

  The demultiplexing unit 1042 demultiplexes the signal input from the radio 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 2A.

  In addition, 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 performs inverse discrete Fourier transform (IDFT) on the PUSCH to obtain modulation symbols, and for each of the PUCCH and PUSCH modulation symbols, BPSK, QPSK, 16QAM, 64QAM, 256QAM, etc. in advance. The received signal is demodulated using the modulation method determined or notified in advance by the own device to the terminal device 2A with the uplink grant.

  The decoding unit 1044 uses the coding rate of the demodulated PUCCH and PUSCH at a coding rate that is determined in advance according to a predetermined encoding method or that the device itself notifies the terminal device 2A with an 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.

  The measurement unit 106 observes the received signal and obtains various measurement values such as RSRP / RSRQ / RSSI. Moreover, the measurement part 106 calculates | requires reception power, reception quality, and a suitable SRS resource index from SRS transmitted from the terminal device.

  FIG. 3 is a schematic block diagram showing the configuration of the terminal device in the present embodiment. As shown in FIG. 3, the terminal device 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 measurement unit ( Measurement step) 205 and transmission / reception antenna 206 are included. 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 A 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 (MAC) layer, a packet data integration protocol (Packet
Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC)
Performs processing of the layer and radio resource control (RRC) layer.

  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.

  The radio resource control unit 2011 manages various setting information of the terminal device itself. Also, the radio resource control unit 2011 generates information arranged in each uplink channel and outputs the information to the transmission unit 203.

  The radio resource control unit 2011 acquires the setting information transmitted from the base station apparatus and outputs the setting information to the control unit 202.

  The scheduling information interpretation unit 2012 interprets downlink control information 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 reception unit 204, the measurement unit 205, and the transmission unit 203 based on the information input from the higher layer processing unit 201. The control unit 202 outputs the generated control signal to the reception unit 204, the measurement unit 205, and the transmission unit 203 to control the reception unit 204 and the transmission unit 203.

  The control unit 202 controls the transmission unit 203 to transmit the CSI / RSRP / RSRQ / RSSI generated by the measurement unit 205 to the base station apparatus.

  The receiving unit 204 separates, demodulates, and decodes the received signal received from the base station device via the transmission / reception antenna 206 in accordance with the control signal input from the control unit 202, and outputs the decoded information to the higher layer processing unit 201. To do. The receiving unit 204 also has a function (step) for performing carrier sense.

  The radio reception unit 2041 converts a downlink signal received via the transmission / reception antenna 206 into a baseband signal by down-conversion, removes unnecessary frequency components, and increases the amplification 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.

  Also, the wireless reception unit 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 demultiplexes the extracted signals into PHICH, PDCCH, EPDCCH, PDSCH, and downlink reference signals. Further, the demultiplexing unit 2042 compensates for the PHICH, PDCCH, and EPDCCH channels based on the channel estimation value of the desired signal obtained from the channel measurement, detects downlink control information, and sends it to the control unit 202. Output. In addition, control unit 202 outputs PDSCH and the channel estimation value of the desired signal 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 measurement unit 205 includes CSI measurement, RRM (Radio Resource Management) measurement, RLM (R
Various measurements such as adio Link Monitoring) are performed to obtain CSI / RSRP / RSRQ / RSSI and the like.

  The transmission unit 203 generates an uplink reference signal according to the control signal input from the control unit 202, encodes and modulates the uplink data (transport block) input from the higher layer processing unit 201, PUCCH, The PUSCH and the generated uplink reference signal are multiplexed and transmitted to the base station apparatus via the transmission / reception antenna 206.

  The encoding unit 2031 performs encoding such as convolutional encoding, block encoding, turbo encoding, LDPC encoding, and Polar encoding on the uplink control information or uplink data input from the higher layer processing unit 201.

  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 uses a physical cell identifier (called physical cell identity: PCI, Cell ID, etc.) for identifying a base station apparatus, a bandwidth for arranging an uplink reference signal, and an uplink grant. A sequence determined by a predetermined rule (formula) is generated based on the notified cyclic shift, the value of a parameter for generating the DMRS sequence, and the like.

  The multiplexing unit 2034 multiplexes the PUCCH and PUSCH signals and the generated uplink reference signal for each transmission antenna port. That is, multiplexing section 2034 arranges the PUCCH and PUSCH signals and the generated uplink reference signal in the resource element for each transmission antenna port.

The radio transmission unit 2035 converts the multiplexed signal into an inverse fast Fourier transform (Inverse Fast Fourier Transform).
Transform (IFFT) to perform OFDM modulation, generate an OFDMA symbol, add a CP to the generated OFDMA symbol, generate a baseband digital signal, and convert the baseband digital signal to an analog signal Then, excess frequency components are removed, converted to a carrier frequency by up-conversion, power amplified, output to the transmission / reception antenna 206 and transmitted.

  Note that the terminal apparatus is not limited to the OFDMA system, and can perform SC-FDMA system modulation.

When ultra-high-capacity communication is required, such as ultra-high-definition video transmission, ultra-wideband transmission utilizing a high frequency band is desired. For transmission in a high frequency band, it is necessary to compensate for path loss, and beam forming is important. In addition, in an environment where a plurality of terminal devices exist in a limited area, when ultra-high capacity communication is required for each terminal device, an ultra-dense network (Ultra-dense network) in which base station devices are arranged at high density. network) is valid. However, when base station apparatuses are arranged at high density, SNR (Signal to noise power ratio: Signal to noise)
Although the power ratio is greatly improved, strong interference due to beamforming may occur. Therefore, in order to realize ultra-high capacity communication for all terminal devices within a limited area, interference control (avoidance, suppression, removal) in consideration of beamforming and / or cooperative communication of a plurality of base stations is required. Necessary.

FIG. 4 shows an example of a downlink communication system according to this embodiment. The communication system shown in FIG. 4 includes a base station device 3A, a base station device 5A, and a terminal device 4A. The terminal device 4A can use the base station device 3A and / or the base station device 5A as a serving cell. When base station apparatus 3A or base station apparatus 5A includes a large number of antennas, the large number of antennas can be divided into a plurality of subarrays (panels and subpanels), and transmission / reception beamforming can be applied to each subarray. In this case, each subarray can include a communication device, and the configuration of the communication device is the same as that of the base station device shown in FIG. 2 unless otherwise specified. Further, when the terminal device 4A includes a plurality of antennas, the terminal device 4A can transmit or receive by beamforming. Further, when the terminal device 4A includes a large number of antennas, the large number of antennas can be divided into a plurality of subarrays (panels and subpanels), and different transmission / reception beamforming can be applied to each subarray. Each subarray can include a communication device, and the configuration of the communication device is the same as the configuration of the terminal device shown in FIG. 3 unless otherwise specified. Note that the base station device 3A and the base station device 5A are also simply referred to as base station devices. The terminal device 4A is also simply referred to as a terminal device.

A synchronization signal is used to determine a suitable transmission beam for the base station apparatus and a suitable reception beam for the terminal apparatus. The base station apparatus transmits a synchronization signal block (SS block, SSB) composed of PSS, PBCH, and SSS. One or more synchronization signal blocks are transmitted in the time domain within the synchronization signal block burst set period set by the base station apparatus, and a time index is set for each synchronization signal block. In the terminal apparatus, the synchronization signal block having the same time index within the synchronization signal block burst set period is delayed spread, Doppler spread, Doppler shift, average gain, average delay, spatial reception parameter, and / or spatial transmission parameter. May be considered to be transmitted from the same position (quasi co-located: QCL) to some extent. Spatial reception parameters are, for example, channel spatial correlation, angle of arrival, and the like. Spatial transmission parameters are, for example, channel spatial correlation, transmission angle (Angle of Departure), and the like. That is, the terminal apparatus can assume that synchronization signal blocks having the same time index are transmitted using the same transmission beam and synchronization signal blocks having different time indexes are transmitted using different beams within the synchronization signal block burst set period. Therefore, if the terminal apparatus reports information indicating a time index of a suitable synchronization signal block within the synchronization signal block burst set period to the base station apparatus, the base station apparatus can know a transmission beam suitable for the terminal apparatus. Further, the terminal apparatus can obtain a reception beam suitable for the terminal apparatus using the synchronization signal blocks having the same time index in different synchronization signal block burst set periods. Therefore, the terminal device can associate the time index of the synchronization signal block with the reception beam direction and / or the subarray. When the terminal device includes a plurality of subarrays, different subarrays may be used when connecting to different cells.

  Moreover, CSI-RS can be used in order to determine the transmission beam of a suitable base station apparatus and the reception beam of a suitable terminal device. The base station apparatus can set the setting information with an upper layer signal. For example, the setting information includes part or all of resource settings and report settings.

The resource setting includes a resource setting ID, a resource setting type, and / or one or more CSI-RS resource set settings. The resource setting ID is used to specify the resource setting. The resource setting type indicates a time domain operation of resource setting. Specifically, the resource setting is a setting for transmitting a CSI-RS aperiodically, a setting for transmitting a CSI-RS periodically, or a semi-persistent CS.
It shows whether it is the setting which transmits I-RS. The CSI-RS resource set configuration includes a CSI-RS resource set configuration ID and / or one or more CSI-RS resource configurations. The CSI-RS resource set setting ID is used to specify the CSI-RS resource set setting. CSI-RS resource setting includes CSI-RS resource setting ID, resource setting type, number of antenna ports, CSI-RS resource mapping, CSI-RS.
And part or all of the power offset of PDSCH. The CSI-RS resource setting ID is used to specify the CSI-RS resource setting, and the CSI-RS resource is associated with the CSI-RS resource setting ID. The CSI-RS resource mapping indicates resource elements (OFDM symbols, subcarriers) in which CSI-RSs in a slot are arranged.

The resource setting is used for CSI measurement or RRM measurement. The terminal apparatus receives the CSI-RS with the set resource, calculates the CSI from the CSI-RS, and reports it to the base station apparatus. Further, when the CSI-RS resource set setting includes a plurality of CSI-RS resource settings, the terminal apparatus receives the CSI-RS with the same reception beam in each CSI-RS resource and calculates the CRI. For example, when the CSI-RS resource set setting includes K (K is an integer of 2 or more) CSI-RS resource settings, the CRI indicates N suitable CSI-RS resources from the K CSI-RS resources. . However, N is a positive integer less than K. In addition, when the CRI indicates a plurality of CSI-RS resources, the terminal device reports CSI-RSRP measured by each CSI-RS resource to the base station device in order to indicate which CSI-RS resource quality is good. Can do. If a base station apparatus performs CSI-RS beamforming (precoding) in different beam directions with a plurality of set CSI-RS resources and transmits them, a base station apparatus suitable for the terminal apparatus by CRI reported from the terminal apparatus Can be known. On the other hand, the reception beam direction of a suitable terminal apparatus can be determined using the CSI-RS resource to which the transmission beam of the base station apparatus is fixed. For example, the base station apparatus transmits information indicating whether or not the transmission beam of the base station apparatus is fixed and / or a period during which the transmission beam is fixed to a certain CSI-RS resource. The terminal apparatus can obtain a suitable reception beam direction from CSI-RSs received in different reception beam directions in the CSI-RS resource to which the transmission beam is fixed. Note that the terminal apparatus may report CSI-RSRP after determining a suitable reception beam direction. When the terminal device includes a plurality of subarrays, the terminal device can select a suitable subarray when obtaining a suitable reception beam direction. Note that a suitable reception beam direction of the terminal device may be associated with the CRI. When the terminal apparatus reports a plurality of CRIs, the base station apparatus can fix the transmission beam with the CSI-RS resource associated with each CRI. At this time, the terminal apparatus can determine a suitable reception beam direction for each CRI. For example, the base station apparatus can transmit the downlink signal / channel and the CRI in association with each other. At this time, the terminal device has to receive with a reception beam associated with the CRI. Moreover, different base station apparatuses can transmit CSI-RSs in a plurality of configured CSI-RS resources. In this case, the network side can know from which base station apparatus the communication quality is good by CRI. Further, when the terminal device includes a plurality of subarrays, reception can be performed by the plurality of subarrays at the same timing. Therefore, if the base station apparatus transmits a CRI in association with each of a plurality of layers (codeword, transport block) in downlink control information or the like, the terminal apparatus uses a subarray and a reception beam corresponding to each CRI, Multiple layers can be received. However, in the case of using an analog beam, when there is one reception beam direction used at the same timing in one subarray, and when two CRIs corresponding to one subarray of the terminal apparatus are set simultaneously, the terminal apparatus It may not be possible to receive with multiple receive beams. In order to avoid this problem, for example, the base station apparatus groups a plurality of set CSI-RS resources, and calculates the CRI using the same subarray in the group. If different subarrays are used between groups, the base station apparatus can know a plurality of CRIs that can be set at the same timing. The CSI-RS resource group may be a CSI-RS resource set. The CRI that can be set at the same timing may be QCL. At this time, the terminal device can transmit the CRI in association with the QCL information. For example, if a terminal device reports CRI that is QCL and CRI that is not QCL separately, the base station device does not set CRI that is QCL at the same timing, and CRI that is not QCL is set at the same timing. Can do. Moreover, the base station apparatus may request CSI for each subarray of the terminal apparatus. In this case, the terminal apparatus reports CSI for each subarray. When reporting a plurality of CRIs to the base station apparatus, the terminal apparatus may report only CRIs that are not QCL.

The report setting is a setting related to CSI reporting, and includes a report setting ID, a report setting type, and / or a report value (amount). The report setting ID is used to specify the report setting. The reported value (amount) is the CSI value (amount) to be reported. The report setting type includes a setting in which the CSI value (amount) is reported periodically, a setting in which the CSI value (amount) is reported periodically, or semi-persistent. ) To report the CSI value (quantity).

  In addition, a codebook in which candidates for a predetermined precoding (beamforming) matrix (vector) are defined is used to determine a transmission beam of a suitable base station apparatus. The base station apparatus transmits CSI-RS, and the terminal apparatus obtains a suitable precoding (beamforming) matrix from the code book, and reports it to the base station apparatus as PMI. Thereby, the base station apparatus can know the transmission beam direction suitable for the terminal apparatus. The codebook includes a precoding (beamforming) matrix for combining antenna ports and a precoding (beamforming) matrix for selecting antenna ports. When using a code book for selecting an antenna port, the base station apparatus can use a different transmission beam direction for each antenna port. Therefore, if the terminal apparatus reports a suitable antenna port as the PMI, the base station apparatus can know a suitable transmission beam direction. Note that a suitable reception beam of the terminal device may be a reception beam direction associated with CRI, or a suitable reception beam direction may be determined again. When a code book for selecting an antenna port is used, if the preferred reception beam direction of the terminal device is the reception beam direction associated with the CRI, the reception beam direction for receiving the CSI-RS is the reception beam associated with the CRI. It is desirable to receive in the direction. Note that the terminal apparatus can associate the PMI and the reception beam direction even when the reception beam direction associated with the CRI is used. Further, when a code book for selecting an antenna port is used, each antenna port may be transmitted from a different base station apparatus (cell). In this case, if the terminal apparatus reports the PMI, the base station apparatus can know which base station apparatus (cell) the communication quality is suitable for. In this case, the antenna port of a different base station apparatus (cell) may not be QCL.

The terminal device 4A may receive an interference signal (adjacent cell interference) from an adjacent cell in addition to the serving cell. The interference signal is a PDSCH, PDCCH, or reference signal of an adjacent cell. In this case, it is effective to remove or suppress the interference signal in the terminal device. As a method for removing or suppressing an interference signal, E-MMSE (Enhanced-Minimum Mean Square Error) for estimating a channel of the interference signal and suppressing it by a linear weight, an interference canceller for generating and removing a replica of the interference signal, and a desired signal And MLD (Maximum Likelihood Detection) for searching a transmission signal candidate for interference signals and detecting a desired signal, R-MLD (Reduced complexity-MLD) for reducing the number of transmission signal candidates and making the calculation amount lower than that of MLD, etc. Applicable. In order to apply these methods, it is necessary to perform channel estimation of the interference signal, demodulation of the interference signal, or decoding of the interference signal. Therefore, in order to efficiently remove or suppress the interference signal, the terminal device needs to know the parameter of the interference signal (adjacent cell). Therefore, the base station apparatus can transmit (set) assist information including parameters of the interference signal (adjacent cell) to the terminal apparatus in order to support the removal or suppression of the interference signal by the terminal apparatus. One or a plurality of assist information is set. The assist information includes, for example, a physical cell ID, a virtual cell ID, a power ratio (power offset) between the reference signal and the PDSCH, a scrambling identity of the reference signal, QCL information (quasi co-location information), CSI-RS resource setting, CSI -R
Number of S antenna ports, subcarrier spacing, resource allocation granularity, resource allocation information, DMRS setting, DMRS antenna port number, number of layers, TDD DL / UL configuration, PMI, RI, modulation scheme, MCS (Modulation and coding scheme) Part or all. The virtual cell ID is an ID virtually assigned to the cell, and there may be cells having the same physical cell ID but different virtual cell IDs. The QCL information is information regarding the QCL for a predetermined antenna port, a predetermined signal, or a predetermined channel. In two antenna ports, if the long-term characteristics of the channel carrying the symbol on one antenna port can be inferred from the channel carrying the symbol on the other antenna port, those antenna ports are QCL It is called. The long interval characteristics include delay spread, Doppler spread, Doppler shift, average gain, average delay, spatial reception parameters, and / or spatial transmission parameters. That is, when the two antenna ports are QCL, the terminal device can be regarded as having the same long section characteristics at the antenna ports. The subcarrier interval indicates a subcarrier interval of the interference signal or a subcarrier interval that may be used in the band. When the subcarrier interval included in the assist information is different from the subcarrier interval used for communication with the serving cell, the terminal device may not remove or suppress the interference signal. A candidate for a subcarrier interval that may be used in the band may indicate a subcarrier interval that is normally used. For example, a subcarrier interval that is normally used may not include a low-frequency subcarrier interval that is used for highly reliable and low-delay communication (emergency communication). The resource allocation granularity indicates the number of resource blocks whose precoding (beamforming) does not change. The DMRS setting indicates a PDSCH mapping type and an additional arrangement of DMRS. DMRS resource allocation varies depending on the PDSCH mapping type. For example, in the PDSCH mapping type A, DMRS is mapped to the third symbol of the slot. Also, for example, PDSCH mapping type B is mapped to the first OFDM symbol of the assigned PDSCH resource. The DMRS additional arrangement indicates whether there is an additional DMRS arrangement or an arrangement to be added. Note that some or all of the parameters included in the assist information are transmitted (set) with higher layer signals. Some or all parameters included in the assist information are transmitted as downlink control information. When each parameter included in the assist information indicates a plurality of candidates, the terminal device blindly detects a suitable one from the candidates. Also, the parameters that are not included in the assist information are blindly detected by the terminal device.

When the terminal apparatus communicates using a plurality of reception beam directions, the surrounding interference state varies greatly depending on the reception beam directions. For example, an interference signal that was strong in one receive beam direction may be weak in another receive beam direction. Assist information for cells that are unlikely to cause strong interference is not only meaningless, but there is a possibility that unnecessary information may be calculated when determining whether or not a strong interference signal is received. Accordingly, the assist information is desirably set for each reception beam direction. However, since the base station device does not necessarily know the reception direction of the terminal device, information related to the reception beam direction may be associated with the assist information. For example, since the terminal apparatus can associate the CRI and the reception beam direction, the base station apparatus can transmit (set) one or a plurality of assist information for each CRI. Further, since the terminal apparatus can associate the time index of the synchronization signal block with the reception beam direction, the base station apparatus can transmit (set) one or a plurality of assist information for each time index of the synchronization signal block. . Further, since the terminal apparatus can associate the PMI (antenna port number) with the reception beam direction, the base station apparatus can transmit (set) one or a plurality of assist information for each PMI (antenna port number). . In addition, when the terminal device includes a plurality of subarrays, the reception beam direction is likely to change for each subarray, so the base station device transmits (sets) one or more assist information for each index associated with the subarray of the terminal device. )can do. When a plurality of base station apparatuses (transmission / reception points) communicate with a terminal apparatus, the terminal apparatuses are likely to communicate with each base station apparatus (transmission / reception point) in a different reception beam direction. Therefore, the base station apparatus transmits (sets) one or a plurality of assist information for each piece of information indicating the base station apparatus (transmission / reception point). The information indicating the base station device (transmission / reception point) may be a physical cell ID or a virtual cell ID. Further, when different DMRS antenna port numbers are used in the base station apparatus (transmission / reception point), information indicating the DMRS antenna port number and the DMRS antenna group is information indicating the base station apparatus (transmission / reception point).

  Note that the number of assist information set by the base station apparatus for each CRI can be made common. Here, the number of assist information refers to the type of assist information, the number of elements of each assist information (for example, the number of cell ID candidates), and the like. In addition, a maximum value is set for the number of pieces of assist information set for each CRI by the base station apparatus, and the base station apparatus can set the assist information for each CRI within the range of the maximum value.

  In addition, when the receiving beam direction of the terminal device changes, there is a high possibility that the transmitting antenna is not QCL. Therefore, the assist information can be associated with the QCL information. For example, when the base station apparatus transmits (sets) assist information of a plurality of cells, a cell that is QCL (or a cell that is not QCL) can be instructed to the terminal apparatus.

  The terminal device removes or suppresses the interference signal using assist information associated with the CRI used for communication with the serving cell.

  In addition, the base station apparatus assists information associated with the reception beam direction (CRI / synchronization signal block time index / PMI / antenna port number / subarray) and the reception beam direction (CRI / synchronization signal block time index / PMI / Assist information that is not associated with (antenna port number / subarray) may be set. Further, the assist information associated with the reception beam direction and the assist information not associated with the reception beam direction may be selectively used depending on capabilities and categories of the terminal device. The capability and category of the terminal device may indicate whether or not the terminal device supports reception beamforming. Further, assist information associated with the reception beam direction and assist information not associated with the reception beam direction may be selectively used in the frequency band. For example, the base station device does not set the assist information associated with the reception beam direction at a frequency lower than 6 GHz. Also, for example, the base station apparatus sets assist information associated with the reception beam direction only at a frequency higher than 6 GHz.

  The CRI may be associated with the CSI resource set setting ID. When instructing the CRI to the terminal device, the base station apparatus may instruct the CRI together with the CSI resource set setting ID. When the CSI resource set setting ID is associated with one CRI or one reception beam direction, the base station apparatus may set assist information for each CSI resource set setting ID.

  In order to know the neighboring cell related to the reception beam direction of the terminal apparatus, the base station apparatus requests the terminal apparatus to perform neighboring cell measurement. The neighbor cell measurement request includes information related to the reception beam direction of the terminal device and a cell ID. When receiving the neighbor cell measurement request, the terminal apparatus measures RSRP / RSRQ / RSSI of the neighbor cell and reports it to the base station apparatus together with information related to the reception beam direction of the terminal apparatus. The information related to the reception beam direction of the terminal device is information indicating the CRI, the time index of the synchronization signal block, the subarray of the terminal device, or the base station device (transmission / reception point).

When the terminal device moves, the surrounding environment may change from moment to moment. Therefore, it is desirable that the terminal device observes surrounding channel conditions, interference conditions, and the like at a predetermined timing and reports them to the base station apparatus. The report results are reported as regular reports or event reports. In the case of periodic reporting, the terminal device periodically measures and reports RSRP / RSRQ by a synchronization signal or CSI-RS. In the case of an event report, an event ID is associated with a report condition. The event ID includes, for example, the following, and a threshold necessary for calculating the condition (threshold 1 and threshold 2 if necessary) and an offset value are also set.
Event A1: When the measurement result of the serving cell becomes better than the set threshold value.
Event A2: When the measurement result of the serving cell becomes worse than the set threshold value.
Event A3: When the measurement result of the adjacent cell becomes better than the set offset value than the measurement result of PCell / PSCell.
Event A4: When the measurement result of the adjacent cell becomes better than the set threshold value.
Event A5: When the measurement result of PCell / PSCell is worse than the set threshold value 1, and the measurement result of the adjacent cell is better than the set threshold value 2.
Event A6: When the measurement result of the adjacent cell becomes better than the set offset value than the measurement result of SCell.
Event C1: When the measurement result in the CSI-RS resource becomes better than the set threshold value.
Event C2: When the measurement result with the CSI-RS resource becomes better than the offset amount than the measurement result with the set reference CSI-RS resource.
Event D1: When the measurement result of the CSI-RS resource different from CRI becomes better than the set threshold value.
Event D2: When the measurement result of the CSI-RS resource related to the CRI becomes worse than the set threshold value.
Event D3: When the measurement result of the reception beam direction not related to the CRI becomes better than the set threshold value.
Event D4: When the measurement result of the SS block index used for synchronization becomes worse than the set threshold value.
Event D5: When the measurement result of the SS block index not used for synchronization becomes worse than the set threshold value.
Event E1: When the time elapsed after the base station apparatus determines the beam exceeds the threshold. Event E2: When the time elapsed since the terminal device decided the beam exceeded the threshold.

  When reporting based on a report setting, a terminal device reports SS-RSRP / SS-RSRQ / CSI-RSRP / CSI-RSRQ / RSSI as a measurement result.

  FIG. 5 shows an example of an uplink communication system according to the present embodiment. The communication system shown in FIG. 5 includes a base station device 7A, a base station device 9A, and a terminal device 6A. The terminal device 6A can use the base station device 7A and / or the base station device 9A as a serving cell. Further, when the base station apparatus 7A or the base station apparatus 9A includes a large number of antennas, the large number of antennas can be divided into a plurality of subarrays (panels and subpanels), and transmission / reception beamforming can be applied to each subarray. In this case, each subarray can include a communication device, and the configuration of the communication device is the same as that of the base station device shown in FIG. 2 unless otherwise specified. Further, when the terminal device 6A includes a plurality of antennas, the terminal device 6A can transmit or receive by beam forming. Further, when the terminal device 6A includes a large number of antennas, the large number of antennas can be divided into a plurality of subarrays (panels and subpanels), and different transmission / reception beamforming can be applied to each subarray. Each subarray can include a communication device, and the configuration of the communication device is the same as the configuration of the terminal device shown in FIG. 3 unless otherwise specified. Note that the base station device 7A and the base station device 9A are also simply referred to as base station devices. The terminal device 6A is also simply referred to as a terminal device.

In the uplink, SRS is used to determine a suitable transmission beam for the terminal apparatus and a suitable reception beam for the base station apparatus. The base station apparatus can transmit (set) setting information related to SRS using a higher layer signal. The setting information includes one or more SRS resource set settings. The SRS resource set setting includes an SRS resource set setting ID and / or one or a plurality of SRS resource settings. The SRS resource set setting ID is used to specify the SRS resource set setting. The SRS resource setting includes an SRS resource setting ID, the number of SRS antenna ports, an SRS transmission comb (Comb), an SRS resource mapping, an SRS frequency hopping, and an SRS resource setting type. The SRS resource setting ID is used to specify the SRS resource setting. The SRS transmission comb indicates the frequency interval of the comb tooth spectrum and the position (offset) within the frequency interval. The SRS resource mapping indicates the OFDM symbol position and the number of OFDM symbols where the SRS is arranged in the slot. The SRS frequency hopping is information indicating SRS frequency hopping. The SRS resource setting type indicates an operation in the time domain of SRS resource setting. Specifically, the SRS resource setting is a setting for transmitting the SRS aperiodically, a setting for transmitting the SRS periodically, or a semi-persistent SRS.
Indicates whether the setting is to transmit.

When a plurality of SRS resources are set, the terminal device can determine a suitable SRS resource by transmitting in a different transmission beam direction for each SRS resource. If the base station apparatus transmits (instructs) an SRS resource indicator (SRS), which is information indicating the SRS resource, to the terminal apparatus, the terminal apparatus preferably uses the transmission beam direction transmitted by the SRS resource. You can know. Note that the base station apparatus can request the terminal apparatus to transmit with the same transmission beam for a predetermined period in order to obtain a suitable reception beam of the base station apparatus. In accordance with the request from the base station apparatus, the terminal apparatus transmits in the same transmission beam direction as that transmitted by the instructed SRI with the instructed SRS resource for the instructed period.

  When the terminal device includes a plurality of subarrays, the terminal device can communicate with a plurality of base station devices (transmission / reception points). In the example of FIG. 5, the terminal device 6A can use the base station device 7A and the base station device 9A as serving cells. In this case, for the terminal device 6A, there is a high possibility that the transmission beam direction suitable for communication with the base station device 7A and the transmission beam direction suitable for communication with the base station device 9A are different. Accordingly, if the terminal device 6A transmits in different transmission beam directions in different subarrays, the terminal station 6A can communicate with the base station device 7A and the base station device 9A at the same timing.

  When transmitting a SRS with a plurality of antenna ports in a certain SRS resource, the terminal device can use different transmission beam directions for each antenna port. In this case, if the base station apparatus instructs the terminal apparatus to perform transmission with a suitable antenna port number, the terminal apparatus can know a suitable transmission beam direction. Note that the base station apparatus can instruct the terminal apparatus to transmit PMI (TPMI) using a code book for selecting an antenna port. The base station apparatus can instruct the terminal apparatus which code book to refer to. The terminal device can use the transmission beam direction corresponding to the antenna port number indicated by TPMI with reference to the instructed code book.

  When the terminal device includes a plurality of subarrays and can transmit at the same timing in the plurality of subarrays, different antenna port numbers can be assigned between the subarrays. At this time, if the terminal apparatus transmits an SRS using a transmission beam from an antenna port with a different subarray and receives TPMI from the base station apparatus, the terminal apparatus can know a suitable subarray and transmission beam direction. Therefore, the terminal apparatus can associate the TPMI with the subarray and the transmission beam direction.

When a terminal device communicates with a plurality of base station devices (transmission / reception points), the same signal (data) can be transmitted to each base station device (transmission / reception point), or different signals (data) can be transmitted. Can be sent. When a terminal device communicates with a plurality of base station devices (transmission / reception points) using the same signal (data), signals received at the plurality of base station devices (transmission / reception points) are combined to improve reception quality. Therefore, it is desirable to perform reception processing in cooperation with a plurality of base station devices (transmission / reception points).

  The base station apparatus can use DCI for PUSCH scheduling. When the terminal apparatus communicates with a plurality of base station apparatuses, each base station apparatus can transmit DCI for PUSCH scheduling. The DCI includes SRI and / or TPMI, and the terminal device can know a suitable transmission beam for the base station device. When the terminal device communicates with a plurality of base station devices, PUSCH can be transmitted to the plurality of base station devices by DCI from one base station device. For example, when DCI includes control information for a plurality of layers (codewords, transport blocks), and when SRI and / or TPMI is instructed (set) for each layer, each layer is associated with each base station apparatus. Is transmitted with a suitable transmission beam. Thereby, the terminal device can transmit different signals (data) to a plurality of base station devices when one DCI is received. Further, DCI includes control information of one layer, and when a plurality of SRIs and / or TPMIs are instructed (set) for one layer, the terminal device uses one transmission beam (same as the same). Data). Thereby, the terminal device can transmit the same signal (data) to a plurality of base station devices when one DCI is received.

  When a terminal device transmits to a plurality of base station devices at the same timing, it is desirable that each base station device knows the communication quality with the terminal device at the same timing. Therefore, the base station apparatus can instruct (trigger) a plurality of SRIs and SRS resources corresponding to each SRI with one DCI. That is, if the terminal apparatus transmits SRS in the transmission beam direction corresponding to each SRI at the same timing, each base station apparatus can know the communication quality with the terminal apparatus at the same timing.

  When the subarrays provided in the terminal apparatus use only one transmission beam direction at the same timing, transmission is performed at the same timing with different subarrays to a plurality of base station apparatuses. At this time, when two SRIs are instructed (set) by one DCI from the base station apparatus, if the two SRIs are associated with the same subarray, the terminal apparatus transmits transmissions corresponding to the two SRIs at the same timing. It may not be possible to execute. In order to avoid this problem, for example, the base station apparatus can set a plurality of SRS resources in groups and request the terminal apparatus to transmit the SRS using the same subarray in the group. Also, if different subarrays are used between groups, the base station apparatus can know a plurality of SRIs that can be set at the same timing. The SRS resource group may be an SRS resource set. Note that SRS (SRS resource) that can be set at the same timing may not be QCL. At this time, the terminal device can transmit the SRS in association with the QCL information. For example, if the terminal device distinguishes and transmits SRS that is QCL and SRS that is not QCL, the base station device does not set SRI that is QCL at the same timing, and sets SRI that is not QCL at the same timing. Can do. Moreover, the base station apparatus may request SRS for each subarray of the terminal apparatus. In this case, the terminal device transmits an SRS for each subarray.

When the terminal apparatus is instructed by the base station apparatus for two SRIs that cannot be transmitted at the same timing, the terminal apparatus performs a beam recovery procedure for performing transmission beam selection again on the base station apparatus. Can be requested. The beam recovery procedure is a procedure performed when the transmission / reception beam tracking is lost between the terminal device and the base station device, and the communication quality is significantly deteriorated. The transmission beam of the station apparatus must be acquired. The terminal apparatus according to the present embodiment is in a state in which the transmission beam itself is secured, but in order to eliminate the state where two SRIs that cannot be transmitted at the same timing are set, a beam recovery procedure is performed. Can be used.

  The terminal device according to the present embodiment can include a plurality of antennas (antenna panels) for which independent beamforming is set. The terminal device according to the present embodiment can use a plurality of antenna panels. Naturally, the terminal device can switch and use the plurality of antenna panels. However, when the antenna panel is not appropriately selected, the transmission quality is significantly deteriorated particularly in high-frequency transmission. Therefore, the terminal apparatus can perform beam scanning (search) with the base station apparatus in order to select beamforming set for the antenna. The terminal device according to the present embodiment can transmit an SRS in order to perform the beam scanning.

The base station apparatus which concerns on this embodiment can notify the information which shows duality (relationship, reciprocity) regarding the propagation (channel) characteristic of a downlink and an uplink with respect to a terminal device. As information regarding propagation characteristics, the base station apparatus can notify the terminal apparatus of information indicating beam correspondence (Beam Correspondence, spatial relation (Spatial relation), spatial relation information (Spatial relation information), reception parameters). Here, beam correspondence is reception beam forming (spatial domain reception filter, reception weight, reception parameter, reception spatial parameter) used when a terminal apparatus receives a downlink signal, and transmission used when transmitting an uplink signal. Information indicating the relationship between beamforming (spatial domain transmission filter, transmission weight, transmission parameter, transmission spatial parameter) is included.

  The base station apparatus can set the beam correspondence for each signal transmitted by the terminal apparatus. For example, the base station apparatus can notify the terminal apparatus of information indicating beam compatibility for the SRS transmitted by the terminal apparatus. The base station apparatus can notify the terminal apparatus of SRS space related information (SRS-SpatialRelationInfo). When the SRS space related information indicates a predetermined signal (value, state), the terminal apparatus can perform SRS transmission using beamforming associated with the predetermined signal. For example, when the SRS space-related information specifies a synchronization signal (SSB and PBCH), the terminal device can transmit the SRS using the reception beamforming used when receiving the synchronization signal. Similarly, the base station apparatus uses space-related information regarding other signals (for example, PUCCH / PUSCH / RS / RACH) transmitted by the terminal apparatus and other signals (for example, PDCCH / PDSCH / RS) received by the terminal apparatus. Can be notified. That is, the base station apparatus can notify the terminal apparatus of the space-related information of the first signal and the second signal. When the terminal device receives the spatial relation information of the first signal and the second signal, and the spatial relation information recognizes that the spatial relation is guaranteed between the first signal and the second signal The second signal can be transmitted (or the second signal is received) using the reception parameter (or the transmission parameter that transmitted the first signal) that has received the first signal.

QCL includes at least the following four types, and parameters that can be regarded as the same are different. The base station apparatus and the terminal apparatus can set any one of the following QCL types between antenna ports (or signals associated with the antenna ports), or can set a plurality of QCL types at the same time. it can.
QCL type A: Doppler shift, Doppler spread, average delay, delay spread
QCL type B: Doppler shift, Doppler spread
QCL type C: Doppler shift, average delay
QCL type D: Spatial Rx

When the PDSCH resource is scheduled using the downlink assignment, the terminal apparatus can set reception beam forming for receiving the PDSCH. At this time, the terminal apparatus can acquire information associated with the reception beamforming from the DCI in which the downlink assignment is described. For example, the terminal device can obtain a transmission configuration indication (TCI) from the DCI. TCI indicates information associated with the QCL related to the antenna port to which the PDSCH is transmitted. The terminal apparatus can set reception beam forming for receiving PDSCH (or DMRS associated with PDSCH) by reading TCI. For example, when the DMRS associated with the SSB and the PDSCH is set to QCL in the TCI with respect to the reception parameter, the terminal apparatus receives the reception beam used when receiving the SSB of the index fed back to the base station apparatus. Can be used. In addition, before the terminal device starts receiving the PDSCH (before the frame including the PDSCH is received by the terminal device), when the DCI acquisition is not in time (the scheduling offset value indicating the time difference between the scheduling information and the PDSCH) When the terminal device is less than the predetermined value), the terminal device can receive the PDSCH according to the TCI default which is a default setting. TCI-default is one of eight TCIs set. Further, when receiving the PDCCH, the terminal apparatus can set the reception beamforming based on the setting of the TCI default.

When transmitting at least part of a signal transmitted by the communication apparatus (including a base station apparatus and a terminal apparatus) in the unlicensed band, the communication apparatus according to the present embodiment prior to signal transmission in the unlicensed band, Career Sense in an unlicensed band (Listen
before talk (LBT), Clear channel assessment (CCA)), and acquire the channel occupation time (or channel transmission permission time).

When communicating in an unlicensed band, the base station apparatus / terminal apparatus can occupy a channel for a certain period of time when it is determined that the channel is idle and carrier sensing is successful. The maximum value of the period during which the channel can be occupied (channel occupation period) is called MCOT (Maximum Channel Occupancy Time). The MCOT varies depending on the priority of data. Data priority can be expressed by a priority class (channel access priority class). The priority classes are indicated by 1, 2, 3, 4 in descending order of priority. In addition, the maximum value of the random period required for the LBT may change depending on the priority class. Note that the random period is a product of a random positive integer equal to or less than the contention window and a slot period (for example, 9 microseconds). A random positive integer equal to or smaller than the contention window size (CWS) is also called a counter in carrier sense (LBT). The CWS may change depending on the priority class, transmission error rate, and the like. Also, if the observed (detected) power is less than the energy detection threshold value in at least a predetermined period (for example, 4 microseconds) in the slot period, the slot period is considered as idle. Otherwise, the slot period is considered busy. If the slot becomes idle in the number of counters, the carrier sense is considered successful. The slot period may vary depending on the frequency band (frequency bandwidth, carrier frequency), and the slot period can be shortened in the high frequency band. Further, the idle / busy period for each slot may be changed depending on the frequency band (frequency bandwidth, carrier frequency). That is, when it is determined that the high frequency band is idle, the period during which the observed (detected) power is less than the energy detection threshold can be shortened.

The base station device can use the energy detection threshold value to determine whether another communication device is performing communication during carrier sense. The base station apparatus can set the energy detection threshold so as to be equal to or less than the maximum energy detection threshold. Since beam forming provides beam gain, when beam forming is assumed, the beam gain can be considered in the energy detection threshold. For example, the offset X dB due to beam forming can be the difference between the gain of the main beam and the gain of the side lobe. At this time, the threshold obtained by raising the energy detection threshold by X dB is the energy detection threshold considering the beam gain. Increasing the energy detection threshold improves the probability of successful carrier sensing, but the area of interference due to beamforming is reduced, so the possibility that the interference power will increase significantly is low. When beam forming is not assumed or when the beam pattern is omnidirectional, X is 0 dB. The offset value X dB by beam forming can be set to a different maximum value depending on the frequency band (frequency bandwidth, carrier frequency) with which the base station apparatus 1A communicates. Further, the offset value X dB by beam forming may be calculated based on equivalent isotropic radiated power (EIRP) including the transmission power of the base station apparatus 1A. The base station device 1A
Whether the offset value X dB by beam forming is set based on the antenna gain or EIRP is determined by the frequency band (frequency bandwidth, carrier frequency) in which the base station apparatus 1A performs communication. it can.

When the communication apparatus sets a plurality of component carriers (or band width parts) as an unlicensed band, the communication apparatus can perform LBT for each component carrier. For example, the communication device can perform carrier sense only for a common time between component carriers, and transmit a frame on the component carrier that has been able to determine that the wireless medium is in an idle state. For example, the communication apparatus can select one component carrier from a plurality of component carriers, and can perform LBT including a random backoff period in the component carrier. At this time, in the component carriers other than the component carrier, the communication device can perform carrier sense from a timing that is back by a predetermined period starting from the timing at which carrier sense of the component carrier is completed. Then, the communication apparatus can transmit a frame in the component carrier that can determine that the wireless medium is in the idle state.

  The communication apparatus performs LBT prior to frame transmission, but since the random backoff period is set to the carrier sense period, the timing at which LBT is completed in the secondary cell is not necessarily the frame boundary (subframe boundary of the primary cell). , Slot boundary, symbol boundary). Therefore, the communication apparatus can transmit a signal from the middle of a frame (subframe, slot, symbol) in order to start transmission of a data signal after completion of LBT. For example, the communication apparatus can transmit a subframe in which 0.5 ms in the first half is blank (null period) when a subframe having a length of 1 ms is transmitted in the secondary cell. For example, the communication apparatus can transmit a subframe in which at least one slot is blank (null period) among a plurality of slots constituting a subframe having a length of 1 ms. For example, the communication apparatus can transmit a slot in which at least one symbol is blank among slots formed of 14 symbols. For example, the communication apparatus can transmit a symbol in which at least one sample is blank among samples constituting the symbol.

Note that when the communication apparatus according to the present embodiment receives a frame partially including a blank as described above, the reception operation for the blank period is not required. However, when the communication apparatus transmits a frame partially including a blank as described above, the communication apparatus can transmit a dummy signal during the blank period. This is because even if the communication device can transmit a frame that partially contains a blank, the timing at which the LBT is completed does not necessarily match the signal transmission timing of the frame that partially contains a blank. It is possible to secure a wireless medium by transmitting a dummy signal between this timing and the signal transmission timing. However, it is needless to say that the communication device does not transmit the dummy signal in a time resource in which the wireless medium cannot be determined to be idle by the LBT.

  In addition, the communication device may have a MCOT end position in the secondary cell that does not match the frame boundary (subframe boundary, slot boundary, symbol boundary). Therefore, the communication device can stop transmission in the middle of a frame (subframe, slot, symbol). For example, when transmitting a subframe having a length of 1 ms in the secondary cell, the communication apparatus can transmit a subframe in which the latter half of 0.5 ms is blank (null period). The subframe blank (null period) is notified to the terminal device by DCI or higher layer signaling.

  Further, when the communication device transmits a frame in the secondary cell, a signal having a comb-like spectrum can be used. Here, the communication apparatus can generate the tooth-like spectrum of the comb in units of resource blocks. For example, the communication apparatus can set one comb tooth as one resource block and set the comb tooth at a cycle of 10 resource blocks. By performing such interlaced transmission, the communication device changes the start position of the comb-tooth shaped spectrum, so that interlace candidates (10 interlaced according to the previous example) are used for transmission by the interval of the comb teeth. Candidate) can be obtained. The communication apparatus can select at least one of a plurality of interlace candidates and transmit a frame, and can transmit a frame using the interlace candidates set by the base station apparatus.

When the terminal device transmits a frame in the secondary cell set to the unlicensed band, in addition to the scheduled uplink transmission (SUL) that transmits the frame according to the scheduling assignment from the base station device, the terminal device autonomously transmits the frame. Frames can be transmitted by autonomous uplink transmission (Autonomous UL (AUL)). The base station apparatus can set the uplink transmission of the terminal apparatus in COT (Channel Occupancy Time) acquired by the LBT. However, the base station apparatus may grant AUL to a part of the time resource of the COT. it can. For example, the base station apparatus can notify the terminal apparatus of information indicating whether or not AUL can be set for a subframe or slot included in the COT. In addition, the base station apparatus can notify the terminal apparatus by DCI whether or not the AUL is actually set in the subframe or slot notified that the AUL can be set. The terminal device can transmit a frame by AUL in a subframe or slot in which AUL is set by the base station device. In the interlace transmission described above, the base station apparatus can notify the terminal apparatus of interlace candidates that can be used in advance for the AUL. Therefore, the terminal apparatus can select at least one of the interlaces that can be used for the AUL. Select to send the frame AUL.

The communication apparatus according to the present embodiment can perform two types of LBT simultaneously or selectively according to the beam setting of the own apparatus. Here, in 1st LBT (1st carrier sense), a communication apparatus implements LBT in consideration of the antenna directivity pattern set to an own apparatus. In the second LBT (second carrier sense), the communication apparatus performs LBT without considering the antenna directivity pattern set in the own apparatus. Alternatively, in the second LBT, a directivity pattern that is wider than the antenna directivity pattern set in the first LBT or a gain directivity pattern lower than the gain of the antenna directivity pattern set in the first LBT is set. To implement. For example, the LBT performed by the communication apparatus setting an antenna directivity pattern having an antenna gain exceeding a predetermined value can be said to be the first LBT. Here, with respect to the antenna gain serving as the reference for the first LBT, for example, the gain difference with respect to the omnidirectional antenna, the gain difference with respect to the dipole antenna, the gain difference between the main lobe and the side lobe, the half-width of the main lobe, etc. Can be defined. In addition, the first LBT that is implemented by setting the antenna directivity pattern that is higher than the antenna gain obtained by the antenna directivity pattern that is set when the communication apparatus performs the second LBT by a predetermined value. It is also possible.

An example of the first LBT will be described. When the communication device can receive a signal using a reception filter (spatial reception filter), the communication device can perform LBT after setting the reception filter. Then, in the COT acquired by the LBT, a signal is transmitted using a transmission filter (spatial transmission filter) that is associated with the reception filter (spatial equivalent, Spatial relation is set). can do. Thus, the first LBT can be said to be the first LBT that is performed after setting the reception filter associated with the transmission filter used in the COT acquired by the LBT.

  In addition, when the terminal apparatus is notified of information associated with the reception filter from the base station apparatus, it can be said that the LBT performed by setting the reception filter is also the first LBT. For example, considering the case where the terminal device is notified of the SRI from the base station device, the terminal device uses the transmission filter set when transmitting the SRS associated with the SRI when transmitting the frame. However, it can be said that the LBT performed by setting the reception filter associated with the transmission filter prior to the transmission of the frame is also the first LBT.

  The communication apparatus according to the present embodiment can selectively use the first LBT and the second LBT. For example, when the transmission power (maximum transmission power, EIRP) set in the transmission unit of the communication device is equal to or higher than a predetermined value, the communication device performs the first LBT, and when the transmission power is lower than the predetermined value, the communication The device can perform a second LBT.

In addition, the communication apparatus uses the first LB according to the frequency band (frequency range) in which the component carrier (or band width part) set to the unlicensed band is arranged.
T and the second LBT can be used selectively. For example, when a communication device transmits a frame on a component carrier arranged at a frequency exceeding a predetermined value, the communication device performs a first LBT prior to the transmission, and otherwise performs a second LBT. can do.

  The communication apparatus according to the present embodiment can set the setting of the first LBT based on the setting of the second LBT. For example, when the antenna included in the communication apparatus performs frame transmission using a beam that realizes an antenna gain that is higher by a predetermined value than the antenna gain that is assumed when the second LBT is performed, the communication apparatus LBT can be performed.

  The communication apparatus according to the present embodiment includes at least two beams (first beam direction and second beam direction, first spatial reception filter and second spatial reception filter, first SSB and second SSB, The first LBT can be implemented assuming a first antenna port, a second antenna port, a first reference signal resource index, and a second reference signal resource index). For example, when the communication device includes two antenna panels, the communication device can simultaneously perform the first LBT in each of the two antenna panels. In the following description, unless otherwise specified, the operation of the communication apparatus using two beams (two antenna panels) is applicable even when the communication apparatus uses three or more beams.

For example, considering a case where the terminal apparatus is notified of two SRIs from the base station apparatus, the terminal apparatus may transmit a frame using a transmission filter associated with the two SRIs. Therefore, the terminal device can set the two reception filters associated with the transmission filters associated with the two SRIs and implement the first LBT. That is, the terminal device performs two operations of the first LBT, but the terminal device may perform two first LBTs simultaneously, or two first LBTs based on a predetermined period. May be selectively performed.

  When the communication apparatus performs the first LBT in each of the two beams (beam direction, antenna port, SSB, reference signal resource index), the communication apparatus can include a random backoff time in the period of performing the LBT. At this time, when the communication apparatus sets a random back-off period for each beam, the LBT period performed by the communication apparatus for each beam is different, and therefore the COT start timings acquired by the communication apparatuses are different. Therefore, the communication apparatus can make the initial value of the random backoff period used in the LBT performed by two beams a common value. For example, the communication apparatus can calculate a random back-off period for each of the two beams, and use the maximum value as the common initial value. In addition, the communication apparatus selects one of the two beams, performs LBT in the period including the random back-off period for the selected beam, and selects the first beam for the other beam. The LBT can be started from a timing that is traced back by a predetermined period with the end of the LBT of the beam as an end point.

Note that the communication device can use the two beams in the acquired COT by performing the first LBT assuming two beams, but naturally the first device assumes one beam. Compared with the case where one LBT is performed and one beam is used, the probability of causing interference to other communication apparatuses increases. Therefore, when performing the LBT assuming a plurality of beams, the communication apparatus can set an LBT threshold (ED threshold) according to the assumed number of beams. For example, the communication apparatus can lower the ED threshold by floor (10 log ₂ (X)) when the number of beams assumed in the LBT is X. For example, the communication apparatus can lower the ED threshold by 3 dB when the number of beams assumed in LBT is 2, and can lower the ED threshold by 6 dB when the assumed number of beams is 4.

  Further, the communication device can change the setting of the first LBT based on communication performed in the COT. The communication device (base station device) can transmit a plurality of SSBs in the COT. The base station apparatus can set the ED threshold value used in the first LBT based on the number of SSBs transmitted in the COT. The base station apparatus can lower the ED threshold as the number of SSBs transmitted in the COT increases. When the base station apparatus transmits a plurality of SSBs in the COT, it is not necessary to lower the ED threshold if the same beam is set for the plurality of SSBs.

  Further, when the communication apparatus (base station apparatus) transmits PDSCH and SSB at the same time in the COT, the ED threshold value used in the first LBT can be lowered. In particular, when different beams are set for the PDSCH and the SSB transmitted simultaneously by the base station apparatus (for example, when the DMRS associated with the SSB and the PDSCH is not the QCL for the spatial parameter), the first The ED threshold used in one LBT can be lowered. At this time, the base station apparatus can perform the first LBT in each of the beam set in the PDSCH and the beam set in the SSB.

Further, the communication device (terminal device) can lower the threshold value of the first LBT in the COT according to the number of SRS to be transmitted. This is because when the terminal device transmits a plurality of SRSs, the SRSs may be transmitted using different beams. Also, the terminal apparatus can set the first LBT threshold according to the number of SRIs notified from the base station apparatus. When the terminal apparatus has a plurality of SRIs notified from the base station apparatus and the antenna port that has transmitted the SRS associated with the SRI is not set to QCL in the reception parameter, the threshold value of the first LBT Can be lowered. In addition, when the terminal apparatus is notified from the base station apparatus of a plurality of SRIs associated with the SRS transmitted from the antenna port not set as QCL, the terminal apparatus transmits the beam used when transmitting the SRS. The assumed first LBT can be performed.

  When the communication apparatus performs the first LBT for each of the two beams, if the wireless medium can be determined to be in an idle state by each LBT, the communication apparatus performs the 2 in the COT acquired by the first LBT. Communication using two beams can be performed. On the other hand, if, in the two first LBTs, the wireless medium is determined to be busy in one first LBT and the wireless medium is determined to be idle in the other first LBT, the communication device , But the beam associated with the first LBT determined to be busy in the COT cannot be used.

  Further, when the communication apparatus performs the first LBT assuming two beams, the first LBT is performed in the beam having the maximum received interference power, and the wireless medium is in an idle state in the first LBT. The communication apparatus can use both of the assumed two beams in the acquired COT, while the first received with the beam having the maximum interference power received. If the wireless medium is determined to be busy in the LBT, the communication device may be set not to acquire the COT.

  When the terminal device performs the first LBT assuming two beams, if the antenna port associated with the two beams can be determined to be QCL with respect to the reception parameter, the terminal device is associated with the two beams. Among the antenna ports, the first LBT can be performed in an antenna port (first antenna port) having a small antenna port number. At this time, in the carrier sense period, a random backoff period (first random number) is performed. Back-off period). On the other hand, in an antenna port other than the antenna port with the smaller antenna port number, the LBT can be started from a timing that is traced back by a predetermined period, with the timing at which the LBT of the antenna port with the smaller antenna port number ends. . This can be implemented, for example, when the reception parameter is QCL between antenna ports that transmit SRSs associated with two SRIs notified from the base station apparatus.

  When the communication device according to the present embodiment performs the first LBT, the communication device sets the carrier sense threshold (ED threshold) based on information associated with the beam assumed in the first LBT. be able to. For example, when the communication device knows that the gain (for example, the gain in the main beam direction, the maximum value of the beam gain) by the beam assumed in the first LBT is X (dBi), the communication sense threshold of the second LBT In comparison, it can be lowered by X dBm. By controlling in this way, the communication device can reduce interference given to other communication devices when a frame is transmitted using the beam associated with the first LBT.

  In addition, when the gain by the beam assumed in the first LBT is known to be X (dBi), the communication apparatus according to the present embodiment can increase by X dBm compared to the carrier sense threshold of the second LBT. it can. This is because when the gain by the beam is increased, it is assumed that the half width of the beam is also reduced.

  Note that the communication apparatus according to the present embodiment sets the first LBT when transmitting using a beam having an antenna gain equal to or greater than a predetermined value for a frame transmitted in the COT acquired by the LBT. Can be changed. For example, when a communication apparatus transmits a frame using a beam having an antenna gain equal to or greater than a predetermined value, the first LBT can be performed using the maximum settable ED threshold.

The communication device can switch between the first LBT and the second LBT based on the priority (priority class) referred to when acquiring the COT. For example, when using a priority class having a low priority (a priority class in which COT that can be acquired by LBT is longer than a predetermined value), the communication apparatus can implement the first LBT.

  The base station apparatus can assign a part of the time resource included in the COT acquired by carrier sense to another communication apparatus (for example, a terminal apparatus connected to the base station apparatus). When the terminal device performs AUL transmission of a frame in the time resource (subframe, slot) assigned by the base station device, the SSB (notified to the base station device) referred to when performing connection processing to the base station device A transmission filter (transmission filter in which a spatial relation is set for the reception filter) associated with the reception filter used when receiving the SSB indicated by the SSB index can be used. Further, when the terminal device transmits a frame in AUL, the terminal device can use a transmission filter associated with the reception filter set in the TCI default.

  Further, when AUL transmission is performed in the time resource assigned to the base station apparatus, the terminal apparatus can transmit a signal in which the SSB and QCL referred to when the connection process is performed on the base station apparatus is set. , A signal can be transmitted from the antenna port that has received the SSB and the antenna port in which the QCL is set.

  In addition, when the terminal apparatus performs AUL transmission in the COT acquired by the base station apparatus, and SUL transmission is set in the same COT, the terminal apparatus uses the reception filter indicated by the TCI described in the DCI assigned to the SUL transmission. On the other hand, a transmission filter in which a spatial relationship is set can be used. Further, the terminal device can use a transmission filter associated with the TCI described in the DCI transmitted when the base station device assigns the SUL transmission most recently performed retroactively from the timing of performing the AUL transmission. .

  When the terminal device performs AUL transmission within the COT acquired by the base station device, the transmission filter associated with the TCI set at the time of SUL transmission from the base station device or the reception filter set to TCI default (When a reception filter indicated by information notified from the base station apparatus and a transmission filter that is not spatially related is used), a random back-off period is included in the carrier sense period prior to the AUL transmission. One LBT can be performed. Here, when the communication apparatus performs the first LBT, the communication apparatus can perform the LBT that does not include the random back-off period in the carrier sense period. In this case, the terminal apparatus lowers the ED threshold value by a predetermined value. be able to.

  When the base station apparatus assigns the acquired time resource in the COT to another communication apparatus (for example, a terminal apparatus), the base station apparatus notifies the terminal apparatus of information indicating whether the time resource can be set to AUL transmission. can do. In addition, the base station apparatus may notify the terminal apparatus that the AUL transmission is actually activated by DCI for the time resource in the acquired COT that can be set for the AUL transmission. it can. When transmitting a frame by AUL transmission in the time resource, the terminal apparatus can set a transmission filter based on the TCI described in the DCI and transmit the frame.

The communication apparatus according to the present embodiment can set whether or not to implement the second LBT for each Bandwidth part (BWP). The base station apparatus according to the present embodiment can set one or a plurality of BWPs in one component carrier.

In addition, the method in which the base station apparatus notifies the terminal apparatus of the information indicating the spatial relation described above is not limited to anything. For example, the base station device can semi-statically set the spatial relationship in the terminal device using higher layer signaling (RRC signaling), and DC
Spatial relations can be set dynamically in the terminal device using I.

  The program that operates in the apparatus related to the present invention may be a program that controls a central processing unit (CPU) or the like to function a computer so as to realize the functions of the embodiments related to the present invention. The program or information handled by the program is temporarily stored in a volatile memory such as a Random Access Memory (RAM), a nonvolatile memory such as a flash memory, a Hard Disk Drive (HDD), or other storage device system.

  A program for realizing the functions of the embodiments according to the present invention 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” refers to a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a medium that dynamically holds a program for a short time, or other recording medium that can be read by a computer. Also good.

  In addition, each functional block or various features of the apparatus used in the above-described embodiments can be implemented or executed by an electric circuit, for example, 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 others Programmable logic devices, discrete gate or transistor logic, discrete hardware components, or a combination 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 by a digital circuit or an analog circuit. In addition, in the case where an integrated circuit technology that replaces the current integrated circuit appears due to progress in semiconductor technology, one or more aspects of the present invention can use a new integrated circuit based on the technology.

  In addition, this invention is not limited to the above-mentioned embodiment. In the embodiment, an example of an 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.

  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 communication device and a communication method.

1A, 3A, 5A, 7A, 9A Base station apparatus 2A, 4A, 6A Terminal apparatus 101 Upper layer processing section 102 Control section 103 Transmission section 104 Reception section 105 Transmission / reception antenna 106 Measurement section 1011 Radio resource control section 1012 Scheduling section 1031 Encoding Unit 1032 modulation unit 1033 downlink reference signal generation unit 1034 multiplexing unit 1035 radio transmission unit 1041 radio reception unit 1042 demultiplexing unit 1043 demodulation unit 1044 decoding unit 201 higher layer processing unit 202 control unit 203 transmission unit 204 reception unit 205 measurement unit 206 Transmission / reception antenna 2011 Radio resource control unit 2012 Scheduling information interpretation unit 2031 Encoding unit 2032 Modulation unit 2033 Uplink reference signal generation unit 2034 Multiplexing unit 2035 Radio transmission unit 2041 Radio reception unit 2042 Demultiplexing unit 2043 No. detection unit

Claims (8)

A communication device for performing a first carrier sense,
A receiver that performs the first carrier sense and secures a wireless medium for a predetermined period;
A transmission unit that transmits a frame using a spatial transmission filter in the predetermined period,
In the predetermined period, when the frame is transmitted using at least two spatial transmission filters, the reception unit is configured to perform the first based on two spatial reception filters associated with the two spatial transmission filters. A communication device that performs carrier sense.   The first random sensing period is included in the first carrier sense period performed by the receiving unit based on a first spatial reception filter of the two spatial reception filters. The communication apparatus according to 1.   A random back-off period included in the first carrier sense period performed by the reception unit based on a second spatial reception filter that is not the first spatial reception filter among the two spatial reception filters, The communication apparatus according to claim 2, wherein the communication apparatus is common to the first random backoff period. The reception unit can further perform a second carrier sense without considering the spatial reception filter,
The reception unit performs the second carrier sense when the maximum transmission power set in the transmission unit is less than a predetermined value, and when the maximum transmission power is a predetermined value or more, The communication apparatus according to claim 1, wherein carrier sense is implemented.   The communication according to claim 4, wherein the reception unit sets a threshold value associated with the first carrier sense based on the spatial transmission filter that is set to a signal that the transmission unit transmits in the predetermined period. apparatus.   When the transmitter transmits a downlink shared channel (PDSCH) and a synchronization signal block (SSB) in the predetermined period, the receiver has QCL (Quasi-colocation) set in the PDSCH and SSB. The communication apparatus according to claim 4, wherein a threshold value associated with the first carrier sense is set to a different value depending on whether the case is not set.   The communication device according to claim 4, wherein the reception unit sets a threshold value associated with the first carrier sense based on the number of acquired SRI (Sounding reference signal resource indicator). A communication method of a communication device that performs first carrier sense,
Performing the first carrier sense and securing a wireless medium for a predetermined period;
A second step of transmitting a frame using a spatial transmission filter during the predetermined period,
When the second step transmits a frame using at least two spatial transmission filters in the predetermined period, the first step includes two spatial reception filters associated with the two spatial transmission filters. A communication method for performing the first carrier sense based on

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