Terminal device, base station device and communication method

Abstract

To provide a terminal device, a base station device and a communication method capable of highly reliable communication or large-capacity communication while avoiding interference when performing transmission by beam forming.SOLUTION: A terminal device comprises: a reception part which receives a downlink control signal (DCI), a predetermined downlink signal, a demodulation reference signal (DMRS), and a downlink sharing channel (PDSCH); a demodulation part which demodulates the PDSCH based upon the DCI and the DMRS; a measurement part which performs carrier sensing; and a transmission part which transmits a report signal. The DCI includes a transmission configuration index (TCI) state, the TCI state indicates information related to pseudo-collocation between the predetermined downlink signal and the DMRS. When the DCI includes a first TCI state and a second TCI state, the carrier sensing is performed based upon the first TCI and the second TCI. The report signal includes a result of the carrier sensing.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a terminal device, a base station device, and a communication method. [Background technology]

[0002] In recent years, research and development activities on the fifth generation mobile wireless communication system (5G system) have been actively carried out. Securing frequency resources is an important issue for communication systems to cope with the rapid increase in data traffic. Therefore, one of the targets of 5G is to realize high-capacity communication using a higher frequency band than the frequency band used in LTE (Long Term Evolution). However, path loss is an issue in wireless communication using a high frequency band. To compensate for path loss, beamforming using multiple antennas is a promising technology (see Non-Patent Document 1).

[0003] Another target for the 5G system is the use of unlicensed bands. Unlicensed bands are bands that do not require a license and have low operating costs, so they are widely used in wireless LANs (Local Area Networks) and other applications. Unlicensed bands support communication in the 60 GHz band, which has a wide bandwidth that can be used to achieve large-capacity transmission. Beamforming is essential for communication in the 60 GHz band. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] EG Larsson, O. Edfors, F. Tufvesson, and TL Marzetta, “Massive MIMO for next generation wireless system,” IEEE Commun. Mag., vol.52, no. 2, pp. 186-195, Feb. 2014. Summary of the Invention [Problem to be solved by the invention]

[0005] However, since beamforming has a high directional gain, even if an interfering communication device is nearby, the interference power is reduced when the beam direction is deviated, but strong interference power is received when the beam direction is aligned. Since the optimal beam direction differs depending on the communication device, the base station device or terminal device communicates while switching the beam direction depending on the communication partner. Dynamic changes in the beam direction mean that the magnitude of the received interference power changes significantly depending on the time, making it difficult to predict the channel quality.

[0006] The present invention has been made in consideration of the above circumstances, and its object is to provide a terminal device, a base station device, and a communication method that are capable of highly reliable communication or large-capacity communication while avoiding interference when the base station device or terminal device transmits using beamforming. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, a terminal device and a communication method according to the present invention are configured as follows.

[0008] A terminal device according to one aspect of the present invention is a terminal device that communicates with a base station device, and includes a receiver that receives a downlink control signal (DCI), the predetermined downlink signal, a demodulation reference signal (DMRS), and a downlink shared channel (PDSCH), a demodulator that demodulates the PDSCH based on the DCI and the DMRS, a measurement unit that performs carrier sense, and a transmitter that transmits a report signal, wherein the DCI includes a transmission configuration indicator (TCI) state, and the TCI state is related to quasi-colocation between the predetermined downlink signal and the DMRS. If the DCI includes a first TCI status and a second TCI status, carrier sensing is performed based on the first TCI and the second TCI, and the report signal includes the carrier sensing result.

[0009] In a terminal device according to one embodiment of the present invention, the DCI includes resource allocation information, and the resource allocation information indicates that the PDSCH is allocated in the slot following the slot in which the DCI is transmitted or later.

[0010] In addition, in a terminal device according to one embodiment of the present invention, the DCI includes resource allocation information, and when the resource allocation information indicates the PDSCH in the same slot as the slot in which the DCI is transmitted, carrier sensing is not performed and the report signal is not transmitted.

[0011] In a terminal device according to an embodiment of the present invention, the report information is transmitted when carrier sense becomes idle in either one or both of the first TCI and the second TCI.

[0012] Furthermore, a base station device according to one embodiment of the present invention is a base station device that communicates with a terminal device, and includes a transmission unit that transmits a downlink control signal (DCI), a specified downlink signal, a demodulation reference signal (DMRS) and a downlink shared channel (PDSCH), and a transmission unit that receives a report signal, wherein the DCI includes a transmission configuration indicator (TCI) state, the TCI state indicating information regarding quasi-colocation between the specified downlink signal and the DMRS, and when the DCI includes a first TCI state and a second TCI state, the report signal includes a carrier sense result based on the first TCI and the second TCI.

[0013] In a base station device according to an embodiment of the present invention, the DCI includes resource allocation information, and the resource allocation information indicates that the PDSCH is to be allocated in the slot following the slot in which the DCI is transmitted or later.

[0014] Moreover, a communication method according to one embodiment of the present invention is a communication method in a terminal device communicating with a base station device, comprising the steps of receiving a downlink control signal (DCI), the specified downlink signal, a demodulation reference signal (DMRS) and a downlink shared channel (PDSCH), demodulating the PDSCH based on the DCI and the DMRS, performing carrier sensing, and transmitting a report signal, wherein the DCI includes a transmission configuration indicator (TCI) state, the TCI state indicating information regarding quasi-colocation between the specified downlink signal and the DMRS, and when the DCI includes a first TCI state and a second TCI state, carrier sensing is performed based on the first TCI and the second TCI, and the report signal includes the carrier sensing result.

[0015] Furthermore, a communication method according to one embodiment of the present invention is a communication method in a base station device communicating with a terminal device, comprising the steps of transmitting a downlink control signal (DCI), a specified downlink signal, a demodulation reference signal (DMRS) and a downlink shared channel (PDSCH), and receiving a report signal, wherein the DCI includes a transmission configuration indicator (TCI) state, the TCI state indicating information regarding quasi-colocation between the specified downlink signal and the DMRS, and when the DCI includes a first TCI state and a second TCI state, the report signal includes a carrier sense result based on the first TCI and the second TCI. Effect of the Invention

[0016] According to the present invention, highly reliable communication and large capacity communication are possible by performing communication using beamforming in a base station device or a terminal device. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram illustrating an example of a communication system according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a block diagram showing a configuration example of a base station device according to the present embodiment. [Diagram 3]FIG. 2 is a block diagram showing an example of the configuration of a terminal device according to the present embodiment. [Figure 4] FIG. 1 is a diagram illustrating an example of a communication system according to an embodiment of the present invention. [Diagram 5] 1A and 1B are diagrams illustrating examples of transmission slots and redundancy versions according to the present embodiment. [Figure 6] FIG. 10 is a diagram illustrating an example of a redundancy version according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The communication system in this embodiment includes base station devices (transmitting devices, cells, transmitting points, transmitting antenna groups, transmitting antenna port groups, component carriers, eNodeB, gNodeB, transmitting points, transmitting / receiving points, transmitting panels, access points, subarrays) and terminal devices (terminals, mobile terminals, receiving points, receiving terminals, receiving devices, receiving antenna groups, receiving antenna port groups, UEs, receiving points, receiving panels, stations, subarrays). A base station device connected to a terminal device (establishing a wireless link) is called a serving cell.

[0019] The base station device and the terminal device in this embodiment can communicate in a frequency band that requires a license (licensed band) and / or a frequency band that does not require a license (unlicensed band). The unlicensed band is also called a shared spectrum channel.

[0020] In this embodiment, "X / Y" includes the meaning of "X or Y". In this embodiment, "X / Y" includes the meaning of "X and Y". In this embodiment, "X / Y" includes the meaning of "X and / or Y".

[0021] Fig. 1 is a diagram showing an example of a communication system according to this embodiment. As shown in Fig. 1, the communication system according to this embodiment includes a base station device 1A and a terminal device 2A. A coverage 1-1 is a range (communication area) in which the base station device 1A can connect to the terminal device. The base station device 1A is also simply called a base station device. The terminal device 2A is also simply called a terminal device.

[0022] 1, the following uplink physical channels are used in uplink wireless communication from the terminal device 2A to the base station device 1A. The uplink physical channels are used to transmit information output from a higher layer. ·PUCCH (Physical Uplink Control Channel) ·PUSCH (Physical Uplink Shared Channel) ·PRACH(Physical Random Access Channel)

[0023] The PUCCH is used to transmit uplink control information (UCI). Here, the uplink control information includes a positive acknowledgement (ACK) or a negative acknowledgement (NACK) (ACK / NACK) for downlink data (downlink transport block, Downlink-Shared Channel: DL-SCH). The ACK / NACK for the downlink data is also called HARQ-ACK or HARQ feedback.

[0024] The uplink control information includes channel state information (CSI) for the downlink. The uplink control information includes a scheduling request (SR) used to request resources for an uplink-shared channel (UL-SCH). The channel state information includes a rank indicator (RI) that designates a suitable spatial multiplexing number, a precoding matrix indicator (PMI) that designates a suitable precoder, a channel quality indicator (CQI) that designates a suitable transmission rate, a CSI-RS (Reference Signal) resource indicator (CRI) that indicates a suitable CSI-RS resource, and a reference signal received power (RSRP) measured by a CSI-RS or a synchronization signal (SS).

[0025] The channel quality indicator CQI (hereinafter, CQI value) can be a suitable modulation scheme (e.g., QPSK, 16QAM, 64QAM, 256QAM, etc.) and coding rate in a predetermined band (details will be described later). The CQI value can be an index (CQI Index) determined by the modulation scheme and coding rate. The CQI value can be a value previously determined by the system.

[0026] The CRI indicates a CSI-RS resource having the best received power / received quality from among a plurality of CSI-RS resources.

[0027] The rank index and the precoding quality index may be predetermined by the system. The rank index and the precoding matrix index may be indexes determined by a spatial multiplexing number or precoding matrix information. Some or all of the CQI value, PMI value, RI value, and CRI value are also collectively referred to as CSI value.

[0028] The PUSCH is used to transmit uplink data (uplink transport block, UL-SCH), and may also be used to transmit ACK / NACK and / or channel state information together with the uplink data, or may be used to transmit only uplink control information.

[0029] The PUSCH is also used to transmit RRC messages, which are information / signals processed in the Radio Resource Control (RRC) layer, and the PUSCH is also used to transmit MAC Control Elements (CEs), which are information / signals processed (transmitted) in the Medium Access Control (MAC) layer.

[0030] For example, the power headroom may be included in the MAC CE and reported via the PUSCH, i.e., a field in the MAC CE may be used to indicate the level of the power headroom.

[0031] The PRACH is used to transmit a random access preamble.

[0032] In uplink wireless communication, uplink reference signals (UL RS) are used as uplink physical signals. The uplink physical signals are not used to transmit information output from a higher layer, but are used by the physical layer. Here, the uplink reference signals include a Demodulation Reference Signal (DMRS), a Sounding Reference Signal (SRS), and a Phase-Tracking reference signal (PT-RS).

[0033] DMRS is related to the transmission of PUSCH or PUCCH. For example, the base station device 1A uses DMRS to perform propagation path correction of PUSCH or PUCCH. For example, the base station device 1A uses SRS to measure the channel state of the uplink. The SRS is also used for observing (sounding) the uplink. The PT-RS is also used to compensate for phase noise. The uplink DMRS is also called the uplink DMRS.

[0034] 1, the following downlink physical channels are used in downlink wireless communication from the base station device 1A to the terminal device 2A. The downlink physical channels are used to transmit information output from a higher layer. PBCH (Physical Broadcast Channel) PCFICH (Physical Control Format Indicator Channel) PHICH (Physical Hybrid automatic repeat request Indicator Channel; HARQ Indication Channel) PDCCH (Physical Downlink Control Channel) EPDCCH (Enhanced Physical Downlink Control Channel) PDSCH (Physical Downlink Shared Channel)

[0035] The PBCH is used to broadcast a Master Information Block (MIB, Broadcast Channel (BCH)) commonly used by terminal devices. The PCFICH is used to transmit information indicating an area (e.g., the number of OFDM (Orthogonal Frequency Division Multiplexing) symbols) used for transmitting the PDCCH. The MIB is also called minimum system information.

[0036] The PHICH is used to transmit an ACK / NACK for uplink data (transport block, codeword) received by the base station apparatus 1A. That is, the PHICH is used to transmit a HARQ indicator (HARQ feedback) indicating an ACK / NACK for the uplink data. The ACK / NACK is also called a HARQ-ACK. The terminal apparatus 2A notifies a higher layer of the received ACK / NACK. The ACK / NACK is an ACK indicating that the data was received correctly, a NACK indicating that the data was not received correctly, or a DTX indicating that there was no corresponding data. In addition, when there is no PHICH for the uplink data, the terminal apparatus 2A notifies a higher layer of the ACK.

[0037] The PDCCH and EPDCCH are used to transmit downlink control information (DCI). Here, multiple DCI formats are defined for the transmission of downlink control information. That is, a field for the downlink control information is defined in the DCI format and mapped to information bits.

[0038] For example, DCI format 1A is defined as a DCI format for the downlink, which is used for scheduling one PDSCH (transmission of one downlink transport block) in one cell.

[0039] For example, the DCI format for the downlink includes downlink control information such as information on resource allocation of the PDSCH, information on the MCS (Modulation and Coding Scheme) for the PDSCH, and a TPC command for the PUCCH. Here, the DCI format for the downlink is also referred to as a downlink grant (or a downlink assignment).

[0040] Furthermore, for example, DCI format 0 is defined as a DCI format for the uplink, which is used for scheduling one PUSCH (transmission of one uplink transport block) in one cell.

[0041] For example, the DCI format for the uplink includes uplink control information such as information on resource allocation of the PUSCH, information on the MCS for the PUSCH, and a TPC command for the PUSCH. The DCI format for the uplink is also referred to as an uplink grant (or an uplink assignment).

[0042] Furthermore, 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).

[0043] In addition, the DCI format for the uplink can be used for a setting indicating an uplink resource to which a channel state information report (CSI feedback report) that the terminal device feeds back to the base station device is mapped. For example, the channel state information report can be used for a setting indicating an uplink resource to which the channel state information (Periodic CSI) is periodically reported. The channel state information report can be used for a mode setting (CSI report mode) to periodically report the channel state information.

[0044] For example, the channel state information report can be used for a setting indicating an uplink resource for reporting aperiodic channel state information (Aperiodic CSI). The channel state information report can be used for a mode setting for reporting aperiodic channel state information (CSI report mode).

[0045] For example, the channel state information report can be used for a setting indicating an uplink resource for reporting semi-persistent channel state information (semi-persistent CSI). The channel state information report can be used for a mode setting (CSI report mode) for reporting channel state information semi-persistently. Note that the semi-persistent CSI report is a periodic CSI report during a period from activation to deactivation by a higher layer signal or downlink control information.

[0046] Furthermore, the DCI format for the uplink can be used for setting the type of channel state information report that the terminal device feeds back to the base station device. The types of channel state information report include wideband CSI (e.g., wideband CQI) and narrowband CSI (e.g., subband CQI).

[0047] When PDSCH resources are scheduled using a downlink assignment, the terminal device receives downlink data through the scheduled PDSCH. When PUSCH resources are scheduled using an uplink grant, the terminal device transmits uplink data and / or uplink control information through the scheduled PUSCH.

[0048] The PDSCH is used to transmit downlink data (downlink transport block, DL-SCH) and a system information block type 1 message, which is cell-specific information.

[0049] Furthermore, the PDSCH is used to transmit a system information message. The system information message includes a system information block X other than the system information block type 1. The system information message is cell-specific information.

[0050] The PDSCH is also used to transmit RRC messages. The RRC message transmitted from the device may be common to a plurality of terminal devices in the cell. Also, the RRC message transmitted from the base station device 1A may be a message (also called dedicated signaling) dedicated to a certain terminal device 2A. That is, user device specific information is transmitted using a message dedicated to a certain terminal device. Also, the PDSCH is used to transmit the MAC CE.

[0051] Herein, the RRC messages and / or MAC CE are also referred to as higher layer signaling.

[0052] In addition, the PDSCH can be used to request downlink channel state information. In addition, the PDSCH can be used to transmit uplink resources that map channel state information reports (CSI feedback reports) that the terminal device feeds back to the base station device. For example, the channel state information reports can be used to periodically request channel state information (PSI). The channel state information report can be used for a mode setting (CSI report mode) for periodically reporting channel state information.

[0053] There are two types of downlink channel state information reports: wideband CSI (e.g., wideband CSI) and narrowband CSI (e.g., subband CSI). Wideband CSI calculates one piece of channel state information for the system band of a cell. Narrowband CSI divides the system band into predetermined units and calculates one piece of channel state information for each division.

[0054] In downlink wireless communication, a synchronization signal (SS) and a downlink reference signal (DL RS) are used as downlink physical signals. The downlink physical signals are not used to transmit information output from higher layers, but are used by the physical layer. The synchronization signals include a primary synchronization signal (PSS) and a secondary synchronization signal (SSS).

[0055] The synchronization signal is used by the terminal device to synchronize the frequency domain and the time domain of the downlink. The synchronization signal is also used to measure the received power, the received quality, or the signal-to-interference and noise power ratio (SINR). The received power measured by the synchronization signal is also called SS-RSRP (Synchronization Signal - Reference Signal Received Power), the received quality measured by the synchronization signal is also called SS-RSRQ (Reference Signal Received Quality), and the SINR measured by the synchronization signal is also called SS-SINR. The SS-RSRQ is the ratio of the SS-RSRP to the RSSI. The RSSI (Received Signal Strength Indicator) is the total average received power in a certain observation period. The synchronization signal / downlink reference signal is also used by the terminal device to perform propagation path correction of the downlink physical channel. For example, the synchronization signal / downlink reference signal is used by the terminal device to calculate the channel state information of the downlink.

[0056] Here, the downlink reference signal includes DMRS (Demodulation Reference Signal), NZP 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). Note that the downlink DMRS is also called downlink DMRS. Note that in the following embodiments, when simply referring to CSI-RS, it includes NZP CSI-RS and / or ZP CSI-RS.

[0057] The DMRS is transmitted in a subframe and band used for transmitting the PDSCH / PBCH / PDCCH / EPDCCH to which the DMRS is associated, and is used for demodulating the PDSCH / PBCH / PDCCH / EPDCCH to which the DMRS is associated.

[0058] The resources of the NZP CSI-RS are set by the base station device 1A. For example, the terminal device 2A uses the NZP CSI-RS to measure signals (channel measurements) or interference. The NZP CSI-RS is also used for beam scanning to search for a suitable beam direction and beam recovery to recover when the received power / received quality in the beam direction deteriorates. The resources of the ZP CSI-RS are set by the base station device 1A. The base station device 1A transmits the ZP CSI-RS with zero output. For example, the terminal device 2A measures interference in resources corresponding to the ZP CSI-RS. Note that the resources for measuring interference corresponding to the ZP CSI-RS are also called CSI-IM (Interference Measurement) resources.

[0059] The base station device 1A transmits (configures) an NZP CSI-RS resource configuration for resources of the NZP CSI-RS. The NZP CSI-RS resource configuration includes one or more NZP CSI-RS resource mappings, a CSI-RS resource ID of each NZP CSI-RS resource, and some or all of the number of antenna ports. The CSI-RS resource mapping is information (e.g., resource elements) indicating the OFDM symbols and subcarriers in the slots in which the CSI-RS resources are arranged. The CSI-RS resource ID is used to identify the NZP CSI-RS resource. Note that the NZP-CSI-RS resource is used for channel measurement or interference measurement.

[0060] The base station device 1A transmits (configures) a CSI-IM resource configuration. The CSI-IM resource configuration includes one or more CSI-IM resource mappings and a CSI-IM resource configuration ID for each CSI-IM resource. The CSI-IM resource mapping is information (e.g., resource elements) indicating the OFDM symbols and subcarriers in a slot in which the CSI-IM resource is allocated. The CSI-IM resource configuration ID is used to identify the CSI-IM configuration resource.

[0061] CSI-RS is also used to measure received power, received quality, or SINR. Received power measured by CSI-RS is also called CSI-RSRP, received quality measured by CSI-RS is also called CSI-RSRQ, and SINR measured by CSI-RS is also called CSI-SINR. Note that CSI-RSRQ is the ratio of CSI-RSRP to RSSI.

[0062] CSI-RS is also transmitted periodically / non-periodically / semi-persistently.

[0063] Regarding CSI, the terminal device is configured by a higher layer. For example, there are a CSI report configuration which is a CSI report configuration, a CSI resource configuration which is a resource configuration for measuring CSI, and a measurement link configuration which links the CSI report configuration and the CSI resource configuration for CSI measurement. In addition, one or more report configurations, resource configurations, and measurement link configurations are configured.

[0064] The CSI reporting configuration includes some or all of the following: resources for channel measurement, CSI-IM resources for interference measurement, NZP-CSI-RS resources for interference measurement, reporting configuration ID, reporting configuration type, codebook configuration, CSI reporting amount, and block error rate target. The reporting configuration ID is used to identify the CSI reporting configuration. The reporting configuration type indicates periodic / non-periodic / semi-persistent CSI reporting. The CSI reporting amount indicates the amount (value, type) to be reported, and is, for example, some or all of CRI, RI, PMI, CQI, or RSRP. The block error rate target is the target of the block error rate assumed when calculating the CQI.

[0065] The CSI resource configuration includes a resource configuration ID, a synchronization signal block resource measurement list, a resource configuration type, and some or all of one or more resource set configurations. The resource configuration ID is used to identify a resource configuration. The synchronization signal block resource configuration list is a list of resources on which measurements using a synchronization signal are performed. The resource configuration type indicates whether the CSI-RS is transmitted periodically, non-periodically, or semi-persistently. In the case of a configuration for transmitting the CSI-RS semi-persistently, the CSI-RS is transmitted periodically during the period from activation to deactivation by a higher layer signal or downlink control information.

[0066] The CSI-RS resource set configuration includes a CSI-RS resource set configuration ID, resource repetition, and part or all of information indicating one or more CSI-RS resources. The resource set configuration ID is used to identify the CSI-RS resource set configuration. Resource repetition indicates ON / OFF of resource repetition within a resource set. When resource repetition is ON, it means that the base station device uses a fixed (same) transmission beam for each of the multiple CSI-RS resources in the resource set. In other words, when resource repetition is ON, the terminal device assumes that the base station device uses a fixed (same) transmission beam for each of the multiple CSI-RS resources in the resource set. When resource repetition is OFF, it means that the base station device does not use a fixed (same) transmission beam for each of the multiple CSI-RS resources in the resource set. In other words, when resource repetition is OFF, the terminal device assumes that the base station device does not use a fixed (same) transmission beam for each of the multiple CSI-RS resources in the resource set. The information indicating the CSI-RS resource includes one or more CSI-RS resource IDs and one or more CSI-IM resource configuration IDs.

[0067] The PT-RS is associated with a DMRS (DMRS port group). The number of antenna ports of the PT-RS is 1 or 2, and each PT-RS port (PT-RS antenna port) is associated with a DMRS port group (DMRS antenna port group). The terminal device assumes that the PT-RS port and the DMRS port (DMRS antenna port) are QCL with respect to delay spread, Doppler spread, Doppler shift, average delay, and spatial reception (Rx) parameters. The base station device sets the PT-RS setting with a higher layer signal. When the PT-RS setting is set, the PT-RS may be transmitted. The PT-RS is not transmitted in the case of a specified MCS (for example, when the modulation method is QPSK). In addition, the PT-RS setting is set with time density and frequency density. The time density indicates the time interval in which the PT-RS is arranged. The time density is indicated as a function of the scheduled MCS. The time density also includes the case where the PT-RS does not exist (is not transmitted). The frequency density indicates the frequency interval in which the PT-RS is arranged. The frequency density is a function of the scheduled bandwidth. The frequency density also includes the absence (not being transmitted) of the PT-RS. Note that if the time density or frequency density indicates that the PT-RS is not present (not being transmitted), then the PT-RS is not present (not being transmitted).

[0068] MBSFN(Multimedia Broadcast multicast service Single Frequency Network) The RS is transmitted in the entire bandwidth of the subframe used for transmitting the PMCH. MBSFN The RS is used to demodulate the PMCH, which is transmitted on the antenna port used to transmit the MBSFN RS.

[0069] 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 signal are collectively referred to as an uplink signal. The downlink physical signals and the uplink physical signals are also collectively referred to as physical signals.

[0070] Moreover, BCH, UL-SCH and DL-SCH are transport channels. A channel used in the MAC layer is called a transport channel. A unit of a transport channel used in the MAC layer is also called a transport block (TB) or a MAC PDU (Protocol Data Unit). A transport block is a unit of data that the MAC layer delivers to the physical layer. In the physical layer, a transport block is mapped to a codeword, and encoding processing and the like are performed for each codeword.

[0071] Furthermore, for a terminal device that supports carrier aggregation (CA), the base station device can communicate by aggregating multiple component carriers (CC) for wider bandwidth transmission. In carrier aggregation, one primary cell (PCell) and one or more secondary cells (SCells) are configured as a set of serving cells.

[0072] In addition, in dual connectivity (DC), a master cell group (MCG) and a secondary cell group (SCG) are configured as groups of serving cells. The MCG is composed of a PCell and optionally one or more SCells. The SCG is composed of a primary SCell (PSCell) and optionally one or more SCells.

[0073] A base station device can communicate using a radio frame. A radio frame is made up of multiple subframes (subintervals). When the frame length is expressed in terms of 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 made up of 10 subframes.

[0074] A slot is composed of 14 OFDM symbols. Since the OFDM symbol length may vary depending on the subcarrier interval, the slot length may also vary depending on the subcarrier interval. A minislot is composed of fewer OFDM symbols than a slot. A slot / minislot can be a scheduling unit. The terminal device can know slot-based scheduling / minislot-based scheduling from the position (placement) of the first downlink DMRS. In slot-based scheduling, the first downlink DMRS is placed in the third or fourth symbol of a slot. In minislot-based scheduling, the first downlink DMRS is placed in the first symbol of scheduled data (resource, PDSCH). Slot-based scheduling is also called PDSCH mapping type A. Minislot-based scheduling is also called PDSCH mapping type B.

[0075] A resource block is defined by 12 consecutive subcarriers. A resource element is defined by a frequency domain index (e.g., a subcarrier index) and a time domain index (e.g., an OFDM symbol index). Resource elements are classified as uplink resource elements, downlink elements, flexible resource elements, and reserved resource elements. In reserved resource elements, a terminal device does not transmit uplink signals and does not receive downlink signals.

[0076] Also, multiple subcarrier spacing (SCS) are supported, for example SCS of 15 / 30 / 60 / 120 / 240 / 480 kHz.

[0077] A base station apparatus / terminal apparatus can communicate in a licensed band or an unlicensed band. The base station apparatus / terminal apparatus can communicate with at least one SCell operating in an unlicensed band by carrier aggregation, with the licensed band being a PCell. The base station apparatus / terminal apparatus can also communicate by dual connectivity, in which a master cell group communicates in a licensed band and a secondary cell group communicates in an unlicensed band. The base station apparatus / terminal apparatus can also communicate only with a PCell in an unlicensed band. The base station apparatus / terminal apparatus can also communicate only with an unlicensed band by CA or DC. Note that communication in which a licensed band is a PCell and a cell (SCell, PSCell) in an unlicensed band is assisted, for example, by CA or DC, is also called LAA (Licensed-Assisted Access). Communication in which a base station apparatus / terminal apparatus communicates only with an unlicensed band is also called unlicensed standalone access (ULSA). In addition, communication between a base station device / terminal device using only licensed bands is also called licensed access (LA).

[0078] Fig. 2 is a schematic block diagram showing the configuration of a base station device in this embodiment. As shown in Fig. 2, the base station device is configured to include 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, a transmission / reception antenna 105, and a measurement unit (measurement step) 106. The upper layer processing unit 101 is configured to include a radio resource control unit (radio resource control step) 1011 and a scheduling unit (scheduling step) 1012. The transmission unit 103 is configured to include an encoding unit (encoding step) 1031, a modulation unit (modulation step) 1032, a downlink reference signal generation unit (downlink reference signal generation step) 1033, a multiplexing unit (multiplexing step) 1034, and a radio transmission unit (radio transmission step) 1035. The receiving unit 104 includes a wireless receiving unit (wireless receiving step) 1041, a demultiplexing unit (demultiplexing step) 1042, a demodulating unit (demodulating step) 1043, and a decoding unit (decoding step) 1044.

[0079] The upper layer processing unit 101 processes the Medium Access Control (MAC) layer, the Packet Data Convergence Protocol (PDCP) layer, the Radio Link Control (RLC) layer, and the Radio Resource Control (RRC) layer. The upper layer processing unit 101 also generates information required for controlling the transmitting unit 103 and the receiving unit 104, and outputs the information to the control unit 102.

[0080] The upper layer processing unit 101 receives information about the terminal device, such as the capabilities of the terminal device (UE capability), from the terminal device. In other words, the terminal device transmits its own capabilities to the base station device by means of upper layer signaling.

[0081] In the following description, information related to a terminal device includes information indicating whether the terminal device supports a specific function or information indicating that the terminal device has completed installation and testing of the specific function. In the following description, whether the terminal device supports a specific function includes whether the terminal device has completed installation and testing of the specific function.

[0082] For example, if a terminal device supports a specific function, the terminal device transmits information (parameters) indicating whether the specific function is supported. If a terminal device does not support a specific function, the terminal device does not transmit information (parameters) indicating whether the specific function is supported. In other words, whether the specific function is supported is notified by whether information (parameters) indicating whether the specific function is supported is transmitted. The information (parameters) indicating whether the specific function is supported may be notified using one bit of 1 or 0.

[0083] The radio resource control unit 1011 generates downlink data (transport block) arranged in the downlink PDSCH, system information, an RRC message, MAC CE, etc., or acquires them from an upper node. The radio resource control unit 1011 outputs the downlink data to the transmission unit 103, and outputs other information to the control unit 102. The radio resource control unit 1011 also manages various setting information of the terminal device.

[0084] The scheduling unit 1012 determines the frequencies and subframes to which the physical channels (PDSCH and PUSCH) are assigned, the coding rates and modulation schemes (or MCSs) of the physical channels (PDSCH and PUSCH), and the transmission power, etc. The scheduling unit 1012 outputs the determined information to the control unit 102.

[0085] The scheduling unit 1012 generates information used for scheduling the physical channels (PDSCH and PUSCH) based on the scheduling result. The scheduling unit 1012 outputs the generated information to the control unit 102.

[0086] The control unit 102 generates a control signal for controlling the transmission unit 103, the reception unit 104, and the measurement unit 106 based on the information input from the upper layer processing unit 101. The control unit 102 generates downlink control information based on the information input from the upper layer processing unit 101, and outputs it to the transmission unit 103.

[0087] The transmitting unit 103 generates a downlink reference signal in accordance with the control signal input from the control unit 102, codes and modulates the HARQ indicator, downlink control information, and downlink data input from the upper layer processing unit 101, multiplexes the PHICH, PDCCH, EPDCCH, PDSCH, and downlink reference signal, and transmits the signal to the terminal device 2A via the transmitting / receiving antenna 105.

[0088] The coding unit 1031 codes the HARQ indicator, downlink control information, and downlink data input from the upper layer processing unit 101 using a predetermined coding method such as block coding, convolution coding, turbo coding, LDPC (Low Density Parity Check) coding, and Polar coding, or codes using a coding method determined by the radio resource control unit 1011. The modulation unit 1032 modulates the coded bits input from the coding unit 1031 using a modulation method that is predetermined or determined by the radio resource control unit 1011, such as BPSK (Binary Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), 16QAM (Quadrature Amplitude Modulation), 64QAM, and 256QAM.

[0089] The downlink reference signal generating unit 1033 generates, as a downlink reference signal, a sequence known to the terminal device 2A, which is found according to a predetermined rule based on a physical cell identifier (PCI, cell ID) for identifying the base station device 1A and the like.

[0090] The multiplexing unit 1034 multiplexes the modulated modulation symbols of each channel, the generated downlink reference signal, and the downlink control information. That is, the multiplexing unit 1034 arranges the modulated modulation symbols of each channel, the generated downlink reference signal, and the downlink control information in resource elements.

[0091] The wireless transmission unit 1035 performs an inverse fast Fourier transform (IFFT) on the multiplexed modulation symbols to generate OFDM symbols, and adds a cyclic prefix (CP) to the OFDM symbols to generate baseband digital signals. The digital signal is converted to an analog signal, the baseband signal is filtered to remove unnecessary frequency components, the signal is up-converted to a carrier frequency, the power is amplified, and the signal is output to the transmitting / receiving antenna 105 for transmission.

[0092] In accordance with the control signal input from the control unit 102, the receiving unit 104 separates, demodulates, and decodes the received signal received from the terminal device 2A via the transmitting / receiving antenna 105, and outputs the decoded information to the upper layer processing unit 101.

[0093] The radio receiving unit 1041 down-converts the uplink signal received via the transmitting / receiving antenna 105 into a baseband signal, removes unnecessary frequency components, controls the amplification level so that the signal level is appropriately maintained, performs quadrature demodulation based on the in-phase and quadrature components of the received signal, and converts the quadrature-demodulated analog signal into a digital signal.

[0094] The wireless receiving unit 1041 removes the portion corresponding to the CP from the converted digital signal. The wireless receiving unit 1041 performs a Fast Fourier Transform (FFT) on the signal from which the CP has been removed, extracts a frequency domain signal, and outputs the signal to the demultiplexing unit 1042.

[0095] The demultiplexing unit 1042 separates the signal input from the radio receiving unit 1041 into signals such as the PUCCH, the PUSCH, and the uplink reference signal. Note that this separation is performed based on radio resource allocation information included in an uplink grant that is determined in advance by the base station apparatus 1A using the radio resource control unit 1011 and notified to each terminal apparatus 2A.

[0096] Moreover, the demultiplexing unit 1042 compensates for the propagation paths of the PUCCH and the PUSCH, and also separates the uplink reference signal.

[0097] The demodulation unit 1043 performs an Inverse Discrete Fourier Transform (IDFT) on the PUSCH to obtain modulation symbols, and demodulates the received signal for each of the modulation symbols of the PUCCH and PUSCH using a predetermined modulation scheme such as BPSK, QPSK, 16QAM, 64QAM, 256QAM, etc., or a modulation scheme that the device itself has notified to the terminal device 2A in advance by an uplink grant.

[0098] The decoding unit 1044 decodes the coded bits of the demodulated PUCCH and PUSCH at a coding rate of a predetermined coding method that is predetermined or that the own device has notified to the terminal device 2A in advance by an uplink grant, and outputs the decoded uplink data and uplink control information to the upper layer processing unit 101. When the PUSCH is retransmitted, the decoding unit 1044 performs decoding using the coded bits held in the HARQ buffer input from the upper layer processing unit 101 and the demodulated coded bits.

[0099] The measurement unit 106 observes the received signal and obtains various measurement values ​​such as RSRP / RSRQ / RSSI. The measurement unit 106 also obtains the received power, the received quality, and a suitable SRS resource index from the SRS transmitted from the terminal device. The measurement unit 106 performs carrier sense in the unlicensed band.

[0100] Fig. 3 is a schematic block diagram showing the configuration of a terminal device in this 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 a transmission / reception antenna 206. The upper layer processing unit 201 includes a radio resource control unit (radio resource control step) 2011 and a scheduling information interpretation unit (scheduling information interpretation step) 2012. The transmission unit 203 includes an encoding unit (encoding step) 2031, a modulation unit (modulation step) 2032, an uplink reference signal generation unit (uplink reference signal generation step) 2033, a multiplexing unit (multiplexing step) 2034, and a radio transmission unit (radio transmission step) 2035. The receiving unit 204 includes a wireless receiving unit (wireless receiving step) 2041, a demultiplexing unit (demultiplexing step) 2042, a demodulating unit (demodulating step) 2043, and a decoding unit (decoding step) 2044.

[0101] 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 also outputs uplink data (transport block) generated by a medium access control (MAC) layer, a packet data integration protocol (PAT) layer, and a packet data integration protocol (PAT) layer. It processes the Data Convergence Protocol (PDCP) layer, the Radio Link Control (RLC) layer, and the Radio Resource Control (RRC) layer.

[0102] The upper layer processing unit 201 outputs, to the transmitting unit 203, information indicating the functions of the terminal device that are supported by the own terminal device.

[0103] The radio resource control unit 2011 manages various setting information of the terminal device itself. The radio resource control unit 2011 also generates information to be allocated to each uplink channel, and outputs the information to the transmission unit 203.

[0104] The radio resource control unit 2011 acquires the setting information transmitted from the base station apparatus, and outputs it to the control unit 202 .

[0105] The scheduling information interpretation unit 2012 interprets the downlink control information received via the receiving unit 204 and determines the scheduling information. In addition, the scheduling information interpretation unit 2012 generates control information for controlling the receiving unit 204 and the transmitting unit 203 based on the scheduling information, and outputs the control information to the control unit 202.

[0106] Based on the information input from the upper layer processing unit 201, the control unit 202 generates a control signal for controlling the receiving unit 204, the measurement unit 205, and the transmitting unit 203. The control unit 202 outputs the generated control signal to the receiving unit 204, the measurement unit 205, and the transmitting unit 203 to control the receiving unit 204 and the transmitting unit 203.

[0107] 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 device.

[0108] In accordance with the control signal input from the control unit 202, the receiving unit 204 separates, demodulates, and decodes the received signal received from the base station device via the transmitting / receiving antenna 206, and outputs the decoded information to the upper layer processing unit 201.

[0109] The wireless receiving unit 2041 down-converts the downlink signal received via the transmitting / receiving antenna 206 into a baseband signal, removes unnecessary frequency components, controls the amplification level so that the signal level is appropriately maintained, performs quadrature demodulation based on the in-phase and quadrature components of the received signal, and converts the quadrature-demodulated analog signal into a digital signal.

[0110] Furthermore, the wireless receiving unit 2041 removes the portion corresponding to the CP from the converted digital signal, performs a fast Fourier transform on the signal from which the CP has been removed, and extracts a signal in the frequency domain.

[0111] The demultiplexing unit 2042 separates the extracted signals into the PHICH, the PDCCH, the EPDCCH, the PDSCH, and the downlink reference signal. , performs channel compensation for the PHICH, PDCCH, and EPDCCH based on the channel estimate of the desired signal obtained from the channel measurement, detects downlink control information, and outputs it to the control unit 202. In addition, the control unit 202 outputs the channel estimate values ​​of the PDSCH and the desired signal to the demodulation unit 2043.

[0112] The demodulation unit 2043 demodulates the PDSCH using the channel estimation value and outputs the result to the decoding unit 2044. The decoding unit 2044 decodes the output of the demodulation unit 2043 and outputs it to the upper layer processing unit 201. When removing or suppressing an interference signal, the demodulation unit 2043 obtains a channel estimation value of the interference channel using the parameters of the interference signal and demodulates the PDSCH.

[0113] The measurement unit 205 performs various measurements such as CSI measurement, RRM (Radio Resource Management) measurement, and RLM (Radio Link Monitoring) measurement, and obtains CSI / RSRP / RSRQ / RSSI, etc. The measurement unit 205 performs carrier sense in the unlicensed band.

[0114] The transmitting unit 203 generates an uplink reference signal in accordance with the control signal input from the control unit 202, codes and modulates the uplink data (transport block) input from the upper layer processing unit 201, multiplexes the PUCCH, PUSCH, and the generated uplink reference signal, and transmits the multiplexed signal to the base station device via the transmitting / receiving antenna 206.

[0115] 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 upper layer processing unit 201.

[0116] The modulation unit 2032 modulates the coded bits input from the coding unit 2031 using a modulation scheme notified by the downlink control information, such as BPSK, QPSK, 16QAM, or 64QAM, or a modulation scheme predetermined for each channel.

[0117] The uplink reference signal generating unit 2033 generates a sequence determined according to a predetermined rule (formula) based on a physical cell identity (PCI, also referred to as Cell ID, etc.) for identifying a base station device, a bandwidth in which the uplink reference signal is allocated, a cyclic shift notified in an uplink grant, parameter values ​​for generating a DMRS sequence, etc.

[0118] The multiplexing unit 2034 multiplexes the PUCCH and PUSCH signals and the generated uplink reference signal for each transmit antenna port. That is, the multiplexing unit 2034 arranges the PUCCH and PUSCH signals and the generated uplink reference signal in resource elements for each transmit antenna port.

[0119] The wireless transmission unit 2035 performs an inverse fast Fourier transform (FFT) on the multiplexed signal. The signal is then modulated according to the OFDM method using an Intermediate Frequency Transform (IFFT), and then modulated using the OFDMA method to generate OFDMA symbols, a CP is added to the generated OFDMA symbols, a baseband digital signal is generated, the baseband digital signal is converted to an analog signal, unnecessary frequency components are removed, the signal is up-converted to a carrier frequency, the power is amplified, and the signal is output to the transmitting / receiving antenna 206 for transmission.

[0120] In addition, the terminal device is not limited to the OFDMA system and can perform modulation according to the SC-FDMA system.

[0121] When ultra-high-capacity communications are required, such as ultra-high definition video transmission, ultra-wideband communications using high frequency bands are used. Transmission in the high frequency band requires compensation for path loss, making beamforming important. Also, in an environment where multiple terminal devices exist in a limited area, when ultra-large capacity communication is required for each terminal device, an ultra-dense network in which base station devices are densely arranged is effective. However, when base station devices are densely arranged, the SNR (signal to noise power ratio) increases, and Although the power ratio is greatly improved, there is a possibility of strong interference due to beamforming. Therefore, in order to realize ultra-large capacity communication for all terminal devices within a limited area, interference control (avoidance, suppression, removal) that takes beamforming into account and / or cooperative communication among multiple base stations is required.

[0122] 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. If the base station device 3A or the base station device 5A includes a large number of antennas, the large number of antennas can be divided into a plurality of subarrays (panel, subpanel, transmitting antenna port, transmitting antenna group, receiving antenna port, receiving antenna group, antenna group, antenna port group), and transmitting / receiving 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 the base station device configuration shown in FIG. 2 unless otherwise specified. If the terminal device 4A includes a plurality of antennas, the terminal device 4A can transmit or receive by beamforming. Furthermore, when the terminal device 4A has many antennas, the many antennas can be divided into multiple subarrays (panel, subpanel, transmitting antenna port, transmitting antenna group, receiving antenna port, receiving antenna group, antenna group, antenna port group), and different transmitting / receiving beamforming can be applied to each subarray. Each subarray can have a communication device, and the configuration of the communication device is the same as the terminal device configuration shown in FIG. 3 unless otherwise specified. Note that the base station device 3A and base station device 5A are also simply called base station devices. Note that the terminal device 4A is also simply called terminal device.

[0123] A synchronization signal is used to determine a suitable transmission beam for the base station device and a suitable reception beam for the terminal device. The base station device transmits a synchronization signal block consisting of PSS, PBCH, and SSS. Note that, within a synchronization signal block burst set period set by the base station device, one or more synchronization signal blocks are transmitted in the time domain, and a time index is set for each synchronization signal block. The terminal device may consider that synchronization signal blocks with the same time index within a synchronization signal block burst set period are transmitted from a relatively same position (quasi co-located: QCL) such that the delay spread, Doppler spread, Doppler shift, average gain, average delay, spatial reception parameters, and / or spatial transmission parameters can be considered to be the same. Note that the spatial reception parameters (Rx parameters, reception filters) are, for example, spatial correlation of the channel, angle of arrival, reception beam direction, etc. Furthermore, the spatial transmission parameters are, for example, spatial correlation of the channel, angle of departure, transmission beam direction, etc. That is, the terminal device can assume that synchronization signal blocks with the same time index within a synchronization signal block burst set period are transmitted by the same transmission beam, and synchronization signal blocks with different time indexes are transmitted by different beams. Therefore, if the terminal device reports information indicating the time index of a suitable synchronization signal block within a synchronization signal block burst set period to the base station device, the base station device can know a transmission beam suitable for the terminal device. Furthermore, the terminal device can obtain a suitable reception beam for the terminal device using a synchronization signal block with the same time index in a different synchronization signal block burst set period. For this reason, the terminal device can associate the time index of the synchronization signal block with the reception beam direction and / or subarray. Note that, when the terminal device has multiple subarrays, different subarrays may be used when connecting to different cells. Note that the time index of the synchronization signal block is also called an SSB index or an SSB resource indicator (SSBRI).

[0124] There are also four QCL types that indicate the state of the QCL. The four QCL types are called QCL type A, QCL type B, QCL type C, and QCL type D, respectively. QCL type A is a relationship (state) in which the Doppler shift, Doppler spread, average delay, and delay spread become QCL. QCL type B is a relationship (state) in which the Doppler shift and Doppler spread become QCL. QCL type C is a relationship (state) in which the average delay and Doppler shift become QCL. QCL type D is a relationship (state) in which the spatial reception parameters become QCL. The above four QCL types can also be combined with each other. For example, QCL type A + QCL type D, QCL type B + QCL type D, etc.

[0125] In addition, one or more TCI (Transmit Configuration Indicator) states are set by a signal of a higher layer. One TCI state can set a QCL type with one or more downlink signals in a certain cell (cell ID) and a certain partial band (BWP-ID). The downlink signals include CSI-RS and SSB. The TCI state is set by an RRC message (signaling), and one or more of the set TCI states are activated / deactivated in the MAC layer. The TCI state can associate a QCL with a downlink signal and a DMRS of a PDSCH. For example, one or more activated TCI states are indicated by a DCI, and can be used for demodulation (decoding) of an associated PDSCH. In addition, when QCL type D is set in the TCI state received by the DCI, the terminal device can know the receiving beam direction (spatial receiving filter) of the associated PDSCH. For this reason, the TCI can be said to be information related to the receiving beam direction of the terminal device. The TCI state can also be associated with the QCL of the downlink signal and the DMRS of the PDCCH. From one or more TCI states set in an RRC message (signaling), one TCI state is activated as a TCI state for the PDCCH in the MAC layer. This allows the terminal device to know the receiving beam direction of the PDCCH DMRS. Note that the default receiving beam direction of the PDCCH DMRS is associated with the SSB index at the time of initial access.

[0126] Also, DMRS for PDSCH or PUSCH is configured as DMRS configuration type 1 (first DMRS configuration type) or DMRS configuration type 2 (second DMRS configuration type). DMRS configuration type 1 supports up to 8 DMRS antenna ports, and DMRS configuration type 2 supports up to 12 DMRS antenna ports. DMRS is also code division multiplexed (CDM) by orthogonal cover code (OCC). The code length of OCC is maximum 4, and has length 2 in the frequency direction and length 2 in the time direction. Front-loaded DMRS is allocated to 1 symbol or 2 symbols. When the front-loaded DMRS is 1 symbol, it cannot be multiplexed in the time direction, so it is multiplexed only in the frequency direction. In this case, it may be called OCC=2. Up to 4 DMRS antenna ports are CDMed by OCC. The 4 DMRS antenna ports that are CDMed are also called CDM group (DMRS CDM group). In this case, DMRS configuration type 1 has two CDM groups, and DMRS configuration type 2 has three CDM groups. DMRSs of different CDM groups are arranged in orthogonal resources. The two CDM groups in DMRS configuration type 1 are also called CDM group 0 (first CDM group) and CDM group 1 (second CDM group). The three CDM groups in DMRS configuration type 2 are also called CDM group 0 (first CDM group), CDM group 1 (second CDM group), and CDM group 2 (third CDM group). In the case of DMRS configuration type 1, CDM group 0 includes DMRS antenna ports 1000, 1001, 1004, and 1005, and CDM group 1 includes DMRS antenna ports 1002, 1003, 1006, and 1007. In the case of DMRS configuration type 2, CDM group 0 includes DMRS antenna ports 1000, 1001, 1006, and 1007, CDM group 1 includes DMRS antenna ports 1002, 1003, 1008, and 1009, and CDM group 2 includes DMRS antenna ports 1004, 1005, 1010, and 1011. Note that a CDM group associated with a DMRS is also referred to as a DMRS CDM group.

[0127] In addition, the DMRS antenna port number for PDSCH or PUSCH and the number of DMRS CDM groups without data are indicated by DCI. The terminal device can know the number of DMRS antenna ports from the number of the indicated DMRS antenna port number. In addition, the number of DMRS CDM groups without data indicates that PDSCH is not arranged in resources in which DMRS of the related CDM group is arranged. In addition, when the number of DMRS CDM groups without data is 1, the reference CDM group is CDM group 0, when the number of DMRS CDM groups without data is 2, the reference CDM groups are CDM group 0 and CDM group 1, and when the number of DMRS CDM groups without data is 3, the reference CDM groups are CDM group 0, CDM group 1 and CDM group 2.

[0128] For example, in the case of MU-MIMO (Multi-User - Multiple Input Multiple Output) transmission, the DMRS for PDSCH or PUSCH may have a different power from the PDSCH. For example, it is assumed that the base station device spatially multiplexes and transmits four-layer PDSCH to each of two terminal devices. That is, the base station device spatially multiplexes and transmits a total of eight layers of PDSCH. In this case, the base station device instructs one terminal device to have the DMRS antenna port number of CDM group 0, and instructs the other terminal device to have the DMRS antenna port number of CDM group 1. The base station device also instructs the two terminal devices that the number of DMRS CDM groups without data is two. In this case, the spatial multiplexing number of DMRS is four, while the spatial multiplexing number of PDSCH is eight, and the power ratio (offset) of DMRS and PDSCH is doubled (3 dB difference). It is also assumed that the base station device spatially multiplexes and transmits four-layer PDSCH to each of three terminal devices. That is, the base station device spatially multiplexes and transmits a total of 12 layers of PDSCH. In this case, the base station device instructs the three terminal devices on the DMRS antenna port numbers of CDM group 0, CDM group 1, and CDM group 2, respectively. The base station device also instructs the three terminal devices on the number of DMRS CDM groups without data as 3. In this case, the spatial multiplexing number of DMRS is 4, while the spatial multiplexing number of PDSCH is 12, and the power ratio of DMRS to PDSCH is three times (4.77 dB difference). Therefore, the base station device or the terminal device transmits DMRS and PDSCH taking into consideration the power ratio of DMRS to PDSCH multiplied by the number of CDM groups. The base station device or the terminal device also demodulates (decodes) PDSCH taking into consideration the power ratio of DMRS to PDSCH multiplied by the number of CDM groups. Note that in the case of SU-MIMO (Single user MIMO) transmission with a large number of spatial multiplexing numbers, the power ratio of DMRS to PDSCH multiplied by the number of CDM groups is also taken into consideration.

[0129] However, when the terminal device communicates with multiple base station devices (transmission / reception points), the power ratio of DMRS and PDSCH may be different from the above. For example, when the terminal device communicates with two base station devices (transmission / reception points), it is assumed that each base station device transmits four-layer PDSCH by spatial multiplexing. In this case, one base station device or two base station devices instruct the number of DMRS CDM groups without data to be two. However, since the spatial multiplexing number of DMRS and the spatial multiplexing number of PDSCH transmitted from each base station device are both four, the power ratio of DMRS and PDSCH is 1 (0 dB), and the power ratio of DMRS and PDSCH does not need to be considered. Therefore, the terminal device needs to know (determine) whether to demodulate (decode) the PDSCH by considering the power ratio of DMRS and PDSCH. Note that when the terminal device communicates with multiple base station devices (transmission / reception points), each base station device (transmission / reception point) may transmit the PDSCH by lowering the power of the PDSCH according to the number of DMRS CDM groups without data, but in this case, reliability and throughput are reduced.

[0130] The base station device can transmit information indicating whether to demodulate (decode) the PDSCH in consideration of the power ratio between the DMRS and the PDSCH or the power ratio between the DMRS and the PDSCH to the terminal device. In this case, the terminal device can demodulate (decode) the PDSCH in accordance with the received information indicating whether to demodulate (decode) the PDSCH in consideration of the power ratio between the DMRS and the PDSCH or the power ratio between the DMRS and the PDSCH.

[0131] The terminal device can also determine the power ratio of DMRS and PDSCH from the setting of the DMRS port group. For example, in DMRS setting type 1, it is assumed that DMRS port group 1 is set (associated) with CDM group 0, that is, DMRS ports 1000, 1001, 1004, and 1005, and DMRS port group 2 is set (associated) with CDM group 1, that is, DMRS ports 1002, 1003, 1006, and 1007. In this case, if the DMRS antenna port numbers set in two DMRS port groups are indicated by DCI, even if the number of DMRS CDM groups without data is indicated as 2, the terminal device demodulates (decodes) the PDSCH with the power ratio of DMRS and PDSCH set to 1 (0 dB). Also, if the DMRS antenna port number set in only one DMRS port group is indicated by DCI, the terminal device demodulates (decodes) the PDSCH with the power ratio of DMRS and PDSCH set to 1 (0 dB).

[0132] Furthermore, the terminal device can also determine the power ratio of DMRS and PDSCH by the TCI. When the received TCI is a setting related to two DMRS port groups, the terminal device demodulates (decodes) the PDSCH with the power ratio of DMRS and PDSCH set to 1 (0 dB) even if the number of DMRS CDM groups without data is 2 or 3. In other cases, the terminal device obtains the power ratio of DMRS and PDSCH according to the number of DMRS CDM groups without data.

[0133] Also, the initial value of the DMRS sequence is calculated based on at least the NID and SCID. At most two types of SCID are set, and are indicated by 0 or 1. The NID is set by a higher layer signal in association with the SCID. For example, the NID when SCID=0 and the NID when SCID=1 are set. If the NID or SCID is not set, SCID=0 and the NID becomes a physical cell ID. The SCID is included in the DCI. Also, the SCID may indicate whether or not to demodulate (decode) the PDSCH taking into account the power ratio between the DMRS and the PDSCH. For example, when SCID=0, the terminal device demodulates (decodes) the PDSCH taking into account the power ratio between the DMRS and the PDSCH according to the number of DMRS CDM groups with no data, and when SCID=1, demodulates (decodes) the PDSCH without taking into account the power ratio between the DMRS and the PDSCH. Also, the SCID may be associated with the DMRS CDM group. For example, if the SCID of a DMRS associated with DMRS CDM group 1 is c, then the SCID of a DMRS associated with DMRS CDM group 2 may be 1-c.

[0134] In addition, when a plurality of base station devices (transmission / reception points) communicate with a terminal device, if each base station device transmits a PDCCH to the terminal device in the same slot, each base station device can spatially multiplex different terminal devices by MU-MIMO. For example, consider a case where PDCCH1 (DCI1) is transmitted from base station device 3A to terminal device 4A, and PDCCH2 (DCI2) is transmitted from base station device 5A to terminal device 4A. Note that PDCCH1 and PDCCH2 are transmitted in the same slot. Although not shown, it is assumed that base station device 5A spatially multiplexes terminal device 4A and terminal device 4B. Also, assuming DMRS setting type 2, base station device 3A assumes that the DMRS port numbers included in DCI1 for terminal device 4A are 1000, 1001, 1006, and 1007, and the number of CDM groups without data is 2. Also, it is assumed that the DMRS port numbers included in DCI1 are 1002, 1003, 1008, and 1009, and the number of CDM groups without data is 3. At this time, base station apparatus 5A communicates with terminal apparatus 4B using DMRS port numbers 1004, 1005, 1010, and 1011. At this time, terminal apparatus 4A can see that DCI1 indicates the DMRS port of DMRS CDM group 1, and DCI2 indicates the DMRS port of DMRS CDM group 2. Therefore, since the two data-free DMRS CDM groups indicated by DCI1 are used for transmission to the terminal apparatus 4A, it can be determined that the power ratio between DMRS DMRS ports 1000, 1001, 1006, and 1007 indicated by DCI1 and the corresponding PDSCH is 1 (0 dB). Furthermore, of the three data-free CDM groups indicated by DCI2, two data-free CDM groups are used for transmission to the terminal apparatus 4A, so it can be determined that the power ratio between DMRS ports 1002, 1003, 1008, and 1009 indicated by DCI2 and the corresponding PDSCH is 2 (3 dB). In other words, when a terminal device receives two PDCCHs in the same slot, it can determine the power ratio of the DMRS and PDSCH by taking into account the number of DMRS CDM groups without data indicated in one DCI minus one.

[0135] Furthermore, signals can be transmitted from a plurality of base station apparatuses (transmission / reception points) using the same or different DMRS ports in one PDCCH.

[0136] When the repetition method is set to any one of FDM method A, FDM method B, and TDM method A in the upper layer signal, the base station device 3A has two TCI states and one DMRS in the DCI. By specifying the DMRS port of the CDM group, the base station apparatus 3A and the base station apparatus 5A can transmit the same transport block (TB) using the same DMRS port to the terminal apparatus 4A. The two TCI states are also referred to as the first TCI and the second TCI, respectively.

[0137] When FDM scheme A is set, the terminal device 4A receives one PDSCH, and the first TCI and the second TCI are each associated with a non-overlapping frequency domain resource allocation. If the non-overlapping frequency domain resources are called the first frequency domain resource and the second frequency domain resource, the terminal device 4A demodulates the first frequency domain resource based on the first TCI and demodulates the second frequency domain resource based on the second TCI.

[0138] When FDM method B is set, the terminal device 4A receives two PDSCHs including the same TB. The two PDSCHs are also called the first PDSCH and the second PDSCH. The first PDSCH and the second PDSCH are assigned to frequency domain resources that do not overlap with each other, and the terminal device 4A demodulates the first PDSCH based on the first TCI and demodulates the second PDSCH based on the second TCI.

[0139] When TDM method A is set, the terminal device 4A receives two PDSCHs (first PDSCH, second PDSCH) including the same TB. The first PDSCH and the second PDSCH are allocated to non-overlapping time domain resources in the same slot, and the terminal device 4A demodulates the first PDSCH based on the first TCI and demodulates the second PDSCH based on the second TCI.

[0140] For example, if the base station device 3A indicates two TCI states (first TCI, second TCI) and DMRS ports of two DMRS CDM groups in the DCI, the base station device 3A and the base station device 5A can transmit signals using different DMRS ports. Of the CDM groups, a DMRS port included in the first DMRS CDM group is also called a first DMRS port, and a DMRS port included in the second DMRS CDM group is also called a second DMRS port. Base station device 3A uses the first DMRS port, and base station device 5A uses the second DMRS port. Also, the first TCI is the first CDM group and The terminal device 4A receives a signal of the first DMRS port based on the first TCI and a signal of the second DMRS port based on the second TCI.

[0141] In addition, the base station device 3A can repeatedly transmit the same transport block (data) in consecutive slots to improve reliability. This type of transmission method is also called slot aggregation. In these consecutive slots, the same symbols are assigned and transmission is limited to a single layer. The number of times the transport block is repeated N slot is set to 2, 4, or 8 by higher layer signaling. slotIf the number of repetitions is not set, the number of repetitions is 1. FIG. 5 shows the relationship between the slot index (slot number) of consecutive slots and the redundancy version. Also, the redundancy version (RV) of the slots that are repeatedly transmitted is determined by the RV indicated by the DCI that schedules the PDSCH as shown in FIG. 5. For example, when the RV indicated by the DCI that schedules the PDSCH is 0, the RVs of the consecutive slots are 0, 2, 3, 1, 0, 2, 3, 1. Also, when the RV indicated by the DCI that schedules the PDSCH is 2, the RVs of the consecutive slots are 2, 3, 1, 0, 2, 3, 1, 0. Also, when the RV indicated by the DCI that schedules the PDSCH is 3, the RVs of the consecutive slots are 3, 1, 0, 2, 3, 1, 0, 2. Also, when the RV indicated by the DCI that schedules the PDSCH is 1, the RVs of the consecutive slots are 1, 0, 2, 3, 1, 0, 2, 3. The redundancy version is used in rate matching for error correction coding. Rate matching is an operation for selecting a predetermined number of bits from a circular buffer consisting of data bits and parity bits. As shown in an example in Figure 6, the redundancy version indicates the starting position when selecting bits to be transmitted from the circular buffer. 601 in Figure 6 represents the circular buffer. For example, when RV=0, the transmission bits are read from the beginning of the data bits.

[0142] In particular, when communicating using beamforming at high frequencies, there is a possibility that communication between a base station device and a terminal device may be blocked by an obstacle (e.g., a person or an object). In this case, by transmitting the same transport block from multiple base station devices, the probability of blocking can be reduced and a decrease in reliability can be prevented. For example, in FIG. 4, if there is an obstacle between the base station device 3A and the terminal device 4A, the communication quality will be significantly degraded, but if there is no obstacle between the base station device 5A and the terminal device 4A, transmission can be performed with good quality.

[0143] When the same transport block is transmitted from multiple base station apparatuses, it is possible to extend slot aggregation to transmission from multiple base station apparatuses. In this case, the same transport block is transmitted in consecutive slots, but by switching the transmitting base station apparatus, it is possible to obtain the effect of reducing the blocking probability and / or improving the reliability per base station apparatus.

[0144] Also, the RV in each of the consecutive slots may be applied in the same manner as in the case of slot aggregation in one base station apparatus shown in FIG. slot If is smaller than 8, different RVs are applied from the two base station devices. However, when slot aggregation is performed with multiple base station devices, if the RVs shown in FIG. 5 are applied, a specific RV (e.g., RV=0) may be applied to the transmission of only one base station device. Also, RV=0 is the redundancy version that contains the most data bits, and blocking of this may lead to a decrease in reliability. Therefore, it is desirable for each base station device to transmit RVs without bias.

[0145] When the terminal device 4A performs receive beamforming, there is a possibility that the spatial receive filter (receive beam direction) is switched between when receiving the base station device 3A and when receiving the base station device 5A. Therefore, in the case of slot aggregation, the terminal device 4A needs to know which spatial receive filter (receive beam direction) to receive in the n-th slot. When the spatial receive filter (receive beam direction) is specified by TCI, the DCI includes two TCIs in which QCL type D is set. These two TCIs are also called the first TCI and the second TCI. If the first TCI corresponds to the first transmission / reception point (base station device 3A) and the second TCI corresponds to the second transmission / reception point (base station device 5A), the terminal device 4A can know which spatial receive filter (receive beam direction, TCI) should be applied in which slot according to the correspondence between the transmission slot and the RV. For example, it can be determined that the first TCI is applied in the even-numbered slots and the second TCI is applied in the odd-numbered slots. The first TCI is N slot It can be determined that the first TCI is applied to the first slot of the first transmission slot, and the second TCI is applied to the second slot of the second transmission slot. Note that the correspondence between the transmission slots and the TCI may also be specified. In this case, the terminal device 4A can know the RV to be applied in each transmission slot from the correspondence between the transmission slots and the TCI. For example, if it is determined that reception is performed with the first TCI in the even slots and with the second TCI in the odd slots, the terminal device 4A can apply RVs in the order of 0, 2, 3, 1 in the even slots, and RVs in the order of 0, 2, 3, 1 in the odd slots. In another example, slot In the case where it is determined that the first slots of the four slots are received with the first TCI and the latter slots are received with the second TCI, the terminal device 4A may apply RVs in the order of 0, 2, 3, 1 in the first slots and 0, 2, 3, 1 in the latter slots. In another example, the first and second slots of the four slots are received with the first TCI, the third and fourth slots are received with the second TCI, and N slot If is 4 or more, repeat this process.

[0146] The first RV of the PDSCH received by the first TCI may be different from the first RV of the PDSCH received by the second TCI. For example, the first TCI may start from RV=0, and the second TCI may start from RV=2. The first RV of the second TCI may be expressed as a difference (shift, offset) from the first RV of the first TCI.

[0147] In order for the terminal device 4A to determine that the signal has been transmitted from a different base station device (transmission / reception point), it is sufficient to know that different QCLs have been set between consecutive slots, and this is not limited to the above-mentioned DMRS CDM group or TCI. For example, if a first QCL is indicated in the even-numbered slots or the first half slots of consecutive slots, and a second QCL is indicated in the odd-numbered slots or the second half slots, the terminal device 4A can determine the redundancy version to be decoded from the relationship between the slot index and the redundancy version.

[0148] In addition, the base station devices 3A and 5A and the terminal device 4A can communicate in an unlicensed band. In an unlicensed band, the base station device / terminal device performs carrier sense and transmits after acquiring a channel occupancy time (COT). Carrier sense is performed to determine whether or not surrounding communication devices are communicating. In addition, carrier sense is performed using LBT (Listen Before Talk). The energy detection threshold is used to determine whether or not surrounding communication devices are communicating, and a default value or a network setting value is used. If the observed reception power (energy) is greater than the energy detection threshold (busy), the base station device / terminal device determines that the surrounding communication devices are communicating and waits for transmission, and if the observed reception power (energy) is less than the energy detection threshold (idle), the base station device / terminal device determines that the surrounding communication devices are not communicating and transmits. In countries and regions where carrier sense is not specified, carrier sense is not required.

[0149] In particular, when performing beamforming, the surrounding communication conditions and interference conditions observed by the base station device may differ significantly from those observed by the terminal device. Even if the carrier sense is idle in the base station device, there is a possibility that the signal may collide with the signal of another communication device in the terminal device. For this reason, it is effective for the transmitting side to know the observation information of the receiving side.

[0150] The base station device can instruct the terminal device to perform carrier sense or report the communication status by using a control signal of an upper layer or a physical layer. When the base station device transmits DCI including multiple TCI states, the terminal device reports carrier sense results for all TCI states or each TCI state. The carrier sense results can indicate idle or busy. When the base station device 3A transmits DCI including two TCI states to the terminal device 4A, the terminal device 4A reports carrier sense results for the two TCI states. In this case, when the terminal device 4A reports that the carrier sense result is an idle state, the base station devices 3A and 5A transmit PDSCH. The terminal device 4A can also report carrier sense results for each TCI state. For example, when the terminal device 4A reports information indicating that the first TCI state is idle and the second TCI is busy, the base station device 3A transmits PDSCH. Also, for example, when the terminal device 4A reports information indicating that the first TCI state is busy and the second TCI is idle, the base station device 5A transmits PDSCH. In addition, when the base station device 3A instructs carrier sense by DCI, the terminal device 4A may report by a response signal (ACK / NACK signal) to the PDCCH. In addition, the terminal device 4A receives the PDCCH based on the first TCI state. Since the response signal can be reported only when the PDCCH can be correctly demodulated, the ACK indicates that both the first TCI state and the second TCI state are idle, and the NACK indicates that the first TCI state is idle. If the PDCCH cannot be correctly demodulated, the response signal is not transmitted. If there is no response signal from the terminal device 4A, the base station device 3A can determine that it is busy in the first TCI state and the second TCI state. In addition, if only one TCI state is included in the DCI, the terminal device 4A has two patterns of transmitting an ACK or transmitting nothing, and does not have to transmit a NACK.

[0151] The period of carrier sense performed by the terminal device 4A in a plurality of TCI states does not necessarily have to be the same. When the first TCI state is set as a default, the period of carrier sense performed in the second TCI state can be made shorter than the period of carrier sense performed in the first TCI state, and the base station device 3A can make the corresponding setting in the terminal device 4A. When the terminal device 4A simultaneously performs carrier sense in the first TCI state and the second TCI state, the terminal device 4A can perform carrier sense associated with the second TCI state from a timing that is a predetermined time period back from the time when the carrier sense performed in the first TCI state is completed as the end time, and at this time, the period of carrier sense associated with the second TCI state can be made shorter than the period of carrier sense associated with the first TCI state. At this time, the terminal device 4A can apply a random backoff (contention window) to the carrier sense associated with the first TCI state, while not applying a random backoff (contention window) to the carrier sense associated with the second TCI state. The base station device 3A can make the relevant settings in the terminal device 4A.

[0152] In addition, when carrier sense is performed simultaneously in the first TCI state and the second TCI state, the end times of the first TCI state and the second TCI state are the same, so that the same carrier sense period can be applied. In this case, the carrier sense period can be the maximum value of the random backoff (contention window) of the first TCI state and the second TCI state.

[0153] When the terminal device 4A performs carrier sensing, a certain period of time is required, so the transmission timing of the PDCCH and the PDSCH requires a certain interval. If the transmission timing of the PDCCH and the PDSCH is within a predetermined period, carrier sense will not be performed in time, so there is no need to report the carrier sense result. PDSCH resource allocation is included in DCI. When the base station device 3A instructs the terminal device 4A to perform carrier sense, it transmits the PDCCH and the PDSCH with a transmission timing of at least a predetermined period. When the base station device 3A does not instruct the terminal device 4A to perform carrier sense, it transmits the PDCCH and the PDSCH with a transmission timing of within a predetermined period. The predetermined period may be determined in advance or may be set by a signal of a higher layer. Furthermore, when the observation period of the terminal device 4A is a fixed length, the predetermined period may be determined based on the observation period of the terminal device 4A. Furthermore, the terminal device 4A can determine whether or not carrier sense is required in the slot to which the PDSCH is assigned. When the PDSCH is assigned to the same slot as the slot to which the PDCCH is transmitted, the terminal device 4A does not report the carrier sense result. Furthermore, when the PDSCH is allocated after the slot next to the slot in which the PDCCH is transmitted, the terminal device 4A reports the carrier sense result. When the base station device 3A instructs the terminal device 4A to report the carrier sense result, it allocates the time domain resource of the PDSCH to the slot next to the slot in which the PDCCH is transmitted, and when it does not instruct the terminal device 4A to report the carrier sense result, it allocates the time domain resource of the PDSCH to the same slot as the PDCCH. Note that when it is instructed to report the carrier sense result, the terminal device 3A transmits a report signal in the same slot as the PDCCH. The resource allocation of the PUCCH / PUSCH to transmit the report signal is instructed by DCI.

[0154] When the DCI includes two TCI states and the terminal device 4A reports that the first TCI state is idle, the base station device 3A transmits a PDSCH. However, since the DCI includes control information related to two TCI states, the control information related to the second TCI state becomes invalid. For example, when different DMRS ports are associated with the first TCI state and the second TCI state, the DMRS port associated with the second TCI state becomes invalid. Also, when different resources are assigned to the first TCI state and the second TCI state, the resource assignment associated with the second TCI state becomes invalid. Also, in the case of slot aggregation, the slot associated with the second TCI state becomes invalid, and the slot is associated with the first TCI state. That is, the slots associated with the first TCI state are transmitted continuously.

[0155] The downlink carrier sense performed by the terminal device 4A can be performed even during CSI measurement. For example, the base station device 3A requests the terminal device 4A to report CSI before transmitting the PDCCH / PDSCH, and the terminal device 4A can include the carrier sense result in the CSI report. In the case of an aperiodic CSI report, a CSI request is set in the DCI that schedules the PUSCH, and the terminal device 4A reports CSI in the PUSCH. The terminal device 4A can include the carrier sense result in the CSI report. When a CSI-RS (or CSI-IM) resource (also called a first CSI-RS (CSI-IM) resource) associated with a first TCI state and a CSI-RS (or CSI-IM) resource (also called a second CSI-RS (CSI-IM) resource) associated with a second TCI state are set in the aperiodic CSI report, the terminal device 4A reports the carrier sense result based on the first TCI state and the second TCI state.

[0156] The terminal device 4A can also periodically perform carrier sensing and periodically report to the base station device 3A. At this time, the base station device 3A can configure the terminal device 4A to include the result of the carrier sensing as Periodic / Semipersistent CSI. When the base station device 3A configures the terminal device with Periodic / Semipersistent CSI at a period longer than a predetermined value, the base station device 3A must not configure the CSI to include the result of the carrier sensing.

[0157] The terminal device 4A can report the result of carrier sense in a frequency band (CC) different from the frequency band (CC) in which the carrier sense was performed. In this case, the frequency band (CC) in which the carrier sense was performed and the frequency band (CC) in which the result of the carrier sense was reported can be set in advance by the base station device 3A. When triggering the terminal device 4A to perform carrier sense, the base station device 3A can set the frequency band (CC) in which the result of the carrier sense is reported to the terminal device.

[0158] The base station device 3A can instruct the terminal device 4A whether to perform carrier sensing when measuring CSI. For example, the base station device 3A can include a carrier sense instruction in DCI that schedules PUSCH. The base station device 3A can also instruct the terminal device 3A to perform carrier sensing by setting the carrier sense result in the report amount included in the CSI report setting. When a CSI report is associated with two TCIs and the carrier sense result and CQI / PMI / RI are set in the report amount, the CQI / PMI / RI based on the TCI in which the carrier sense became idle is reported. When the CQI / PMI / RI is reported, the carrier sense result does not need to be reported. When the carrier sense based on the first TCI state and the second TCI state becomes busy, the terminal device 4A reports only the carrier sense result or does not report anything.

[0159] The terminal device 4A performs carrier sense during CSI measurement using the interference measurement resource. The interference measurement resource is, for example, a CSI-IM resource. When a CSI report is requested by DCI, if a channel measurement resource is not set and only a CSI-IM resource is set, even if the DCI does not include an instruction for carrier sense, the terminal device 4A reports the carrier sense result. At this time, even if the report amount includes CQI / PMI / RI, the terminal device 4A reports only the carrier sense result without reporting CQI / PMI / RI. The carrier sense result includes the case where the received power is observed during carrier sense. The carrier sense result also includes the case where the allowable interference power is observed during carrier sense. Here, the allowable interference power can be an interference power that can demodulate a data signal within a predetermined error rate even if observed at the same time when a data signal transmitted with an MCS set in the most recent PDSCH is received for the subframe (slot) in which the carrier sense is performed.

[0160] Since the interference conditions observed by the base station device and the terminal device are different, the so-called hidden terminal problem occurs. As a countermeasure against the hidden terminal problem, the base station device / terminal device can transmit a reservation signal for setting a transmission inhibition period to surrounding communication devices after becoming idle by carrier sense. The reservation signal includes a source, a destination, and a part or all of the transmission inhibition period length. The source is an identifier (address) of the communication device that transmits the reservation signal, an identifier of a system including the communication device that transmits the reservation signal, or an identifier of an operator that provides a service to the communication device that transmits the reservation signal. The destination is an identifier (address) of a communication device that does not set a transmission inhibition period. If the destination is not the communication device itself, the communication device that receives the reservation signal waits for transmission for the set transmission inhibition period length. This allows the transmission inhibition period to be set for communication devices around the base station device or communication devices around the terminal device, so that communication with good quality can be achieved. However, the reservation signal cannot be fully effective unless it can be received by other base station devices / terminal devices or communication devices of other operators. In general, to enhance safety, the control channel and the shared channel are scrambled and transmitted with a predetermined ID such as C-RNTI (Cell - Radio Network Temporary Identifier). For this reason, it is necessary to share an ID (RNTI) for scrambling the reservation signal with other base station devices / terminal devices and communication devices of other operators. Information can be shared between base station devices via the X2 interface or other interfaces that can be used for transmission and reception between base station devices. After sharing the information, each base station device can set the RNTI of the reservation signal to the terminal device via a higher layer signal.

[0161] Generally, a downlink channel is transmitted by a base station device and received by a terminal device. An uplink channel is transmitted by a terminal device and received by a base station device. Therefore, a base station device can set a transmission prohibition period to surrounding terminal devices by transmitting a reservation signal, for example, by PDCCH. A terminal device can set a transmission prohibition period to surrounding base station devices by transmitting a reservation signal, for example, by PUCCH. A terminal device can set a transmission prohibition period to surrounding terminal devices by transmitting a reservation signal, for example, by PDCCH. When a terminal device transmits a PDCCH, a resource of the PDCCH transmitted by the terminal device may be determined in advance for each base station device (or cell) so as not to conflict with the PDCCH transmitted by the base station device. For example, the resource of the PDCCH is determined based on a cell ID. When a terminal device transmits a PDCCH, an OFDM waveform is used as a signal waveform, so that surrounding terminal devices can monitor the PDCCH in the same way as other downlink signals. On the other hand, a terminal device can also transmit a PDCCH using an SC-FDMA waveform (a signal to which precoding is applied). In this case, the base station device can set the terminal device to monitor the signal of the SC-FDMA waveform. The communication device can set the subcarrier interval of the reservation signal to be transmitted. For example, the communication device can set the subcarrier interval so that the reservation signal can be received by a communication device of a predetermined communication standard. In this case, the communication standard assumed by the communication device can be a standard with a subcarrier interval of 312.5 kHz or a standard with a subcarrier interval of 78.125 kHz. In addition, when the subcarrier interval with which the communication device transmits a data signal is 60 kHz, the communication device can set the subcarrier interval to 15 kHz and transmit the reservation signal.

[0162] In addition, when a base station device (or a terminal device) transmits a reservation signal, if a communication device other than the destination communication device receives the reservation signal, the communication device sets a transmission inhibition period based on the reservation signal. On the other hand, if the communication device that received the reservation signal is in an exposed terminal state with respect to the communication device that transmitted the reservation signal or the communication device that is the destination of the reservation signal, setting a transmission inhibition period based on the reservation signal simply results in a loss of communication opportunities. Therefore, the communication device according to the present embodiment can add information associated with a condition under which a transmission inhibition period does not need to be set to the reservation signal. For example, the allowable interference power in the communication device that transmitted the reservation signal can be described as the information. For example, information indicating a communication device that does not need to set a transmission inhibition period to the reservation signal can be described as the information.

[0163] The frequency bands used by the communication devices (base station devices, terminal devices) according to this embodiment are not limited to the licensed bands and unlicensed bands described above. The frequency bands covered by this embodiment include frequency bands called white bands (white spaces) that are not actually used for the purpose of preventing interference between frequencies even though permission for use for specific services is given by a country or region (for example, frequency bands that are allocated for television broadcasting but are not used in some regions), and shared frequency bands (license-sharing bands) that have been exclusively allocated to specific operators but are expected to be shared by multiple operators in the future.

[0164] The program that runs on the device according to the present invention may be a program that controls a Central Processing Unit (CPU) or the like to make a computer function so as to realize the functions of the embodiments according 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 non-volatile memory such as a flash memory, a Hard Disk Drive (HDD), or other storage device system.

[0165] The program for implementing the functions of the embodiments of the present invention may be recorded on a computer-readable recording medium. The program may be realized by having the program loaded into a computer system and executing it. The "computer system" here means a computer system built into a device, and includes hardware such as an operating system and peripheral devices. The "computer-readable recording medium" may be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a medium that dynamically holds a program for a short period of time, or any other computer-readable recording medium.

[0166] In addition, each functional block or feature of the device used in the above-mentioned embodiment may be implemented or performed by an electric circuit, for example, an integrated circuit or a plurality of integrated circuits. The electric circuit designed to perform the functions described herein may include a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or a combination thereof. The general-purpose processor may be a microprocessor, or a conventional processor, controller, microcontroller, or state machine. The electric circuit described above may be composed of a digital circuit or an analog circuit. In addition, when a technology for integrated circuitization that replaces current integrated circuits appears due to the progress of semiconductor technology, one or more aspects of the present invention may use a new integrated circuit according to that technology.

[0167] The present invention is not limited to the above-described embodiment. In the embodiment, an example of a device is described, but the present invention is not limited to this, and can be applied to stationary or non-movable electronic devices installed indoors or outdoors, such as terminal devices or communication devices of AV equipment, kitchen equipment, cleaning / washing equipment, air conditioners, office equipment, vending machines, and other household appliances.

[0168] Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like within the scope of the gist of the present invention are also included. Furthermore, the present invention can be modified in various ways within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. Furthermore, configurations in which elements described in the above embodiments are replaced with elements that have the same effect are also included. [Industrial Applicability]

[0169] The present invention is suitable for use in a terminal device, a base station device, and a communication method. [Explanation of symbols]

[0170] 1A, 3A, 5A base station equipment 2A, 4A terminal equipment 101 Upper layer processing unit 102 Control section 103 Transmitter 104 Receiving unit 105 Transmitting and Receiving Antenna 106 Measuring section 1011 Radio resource control unit 1012 Scheduling Department 1031 Encoding section 1032 Modulation section 1033 Downlink reference signal generator 1034 Multiplex section 1035 Radio transmitter 1041 Radio receiver 1042 Demultiplexer 1043 Demodulation section 1044 Decryption Unit 201 Upper layer processing unit 202 Control section 203 Transmitter 204 Receiving section 205 Measuring section 206 Transmitting and Receiving Antenna 2011 Radio Resource Control Unit 2012 Scheduling Information Interpretation Department 2031 Encoding section 2032 Modulation section 2033 Uplink reference signal generator 2034 Multiplex section 2035 Radio transmitter 2041 Radio receiver 2042 Demultiplexer 2043 Demodulation section 2044 Decoding Unit 601 Circular Buffer

Claims

1. A terminal device that communicates with a base station device, A receiving unit that receives a downlink control signal (DCI), the predetermined downlink signal, a demodulation reference signal (DMRS), and a downlink shared channel (PDSCH); A demodulation unit that demodulates the PDSCH based on the DCI and the DMRS; A measurement unit that performs carrier sense; A transmitter that transmits a report signal, The DCI includes a transmission configuration indicator (TCI) status; The TCI state indicates information regarding quasi-colocation between a given downlink signal and the DMRS; If the DCI includes a first TCI status and a second TCI status, performing a carrier sense based on the first TCI state and the second TCI state; the report signal includes the carrier sense result; Terminal device.

2. The DCI includes resource allocation information, The resource allocation information indicates that the PDSCH is allocated after the slot next to the slot in which the DCI is transmitted. The terminal device according to claim 1 .

3. The DCI includes resource allocation information, If the resource allocation information indicates the PDSCH in the same slot as the slot in which the DCI is transmitted, carrier sensing is not performed and the report signal is not transmitted. The terminal device according to claim 1 .

4. The report signal is transmitted when a carrier sense becomes idle in either one or both of the first TCI state and the second TCI state. The terminal device according to claim 1 .

5. A base station device that communicates with a terminal device, A transmitter that transmits a downlink control signal (DCI), a predetermined downlink signal, a demodulation reference signal (DMRS), and a downlink shared channel (PDSCH); A transmitter for receiving a report signal, The DCI includes a transmission configuration indicator (TCI) status; The TCI state indicates information regarding quasi-colocation between the predetermined downlink signal and the DMRS; If the DCI includes a first TCI status and a second TCI status, the report signal includes a carrier sense result based on the first TCI state and the second TCI state. Base station equipment.

6. The DCI includes resource allocation information, The resource allocation information indicates that the PDSCH is allocated after the slot next to the slot in which the DCI is transmitted. The base station device according to claim 5 .

7. A communication method in a terminal device that communicates with a base station device, comprising: receiving a downlink control signal (DCI), the predetermined downlink signal, a demodulation reference signal (DMRS), and a downlink shared channel (PDSCH); demodulating the PDSCH based on the DCI and the DMRS; performing a career sense; transmitting a report signal; The DCI includes a transmission configuration indicator (TCI) status; The TCI state indicates information regarding quasi-colocation between a given downlink signal and the DMRS; If the DCI includes a first TCI status and a second TCI status, performing a carrier sense based on the first TCI state and the second TCI state; the report signal includes the carrier sense result; Communication methods.

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