JP2020043508A - Terminal device, base station device, and communication method - Google Patents

Abstract

To provide a terminal device, a base station device, and a communication method, for efficiently performing broadband communication.SOLUTION: The terminal device for receiving a DCI format used for PDSCH scheduling, includes: a receiving unit for receiving the DCI format including an identifier indicating an uplink frequency band used for feedback of HARQ-ACK for PDSCH; and a transmission unit for readjusting an RF part to the uplink frequency band, and when receiving an instruction to trigger transmission of HARQ-ACK feedback from a base station apparatus, transmitting HARQ-ACK in the readjusted uplink frequency band.SELECTED DRAWING: Figure 10

Description

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

Radio access method and radio network of cellular mobile communication (hereinafter, "Long Term Evolution (LTE)" or "EUTRA: Evolved Universal T"
errestrial Radio Access ". ) Is specified in the third generation partnership project (3GPP: 3rd Generation Partnership Project). In LTE, a base station device is also called an eNodeB (evolved NodeB), and a terminal device is also called a UE (User Equipment). LTE is a cellular communication system in which a plurality of areas covered by a base station device are arranged in a cell shape. A single base station device may manage a plurality of cells.

  In 3GPP, the next generation standard (NR: New Radio) is studied in order to propose to IMT (International Mobile Telecommunication) -2020 which is a standard of a next generation mobile communication system formulated by the International Telecommunication Union (ITU). (Non-Patent Document 1). In a single technology framework, the NR is based on a scenario that satisfies the requirements of three scenarios that satisfy eMBB (enhanced Mobile Broadband), mMTC (massive Machine Type Communication), and URLLC (ultra reliable and low latency). I have.

  In addition, application of NR in an unlicensed spectrum (Unlicensed Spectrum) is being studied (Non-Patent Document 2). It has been studied to realize a data rate of several Gbps by applying an NR supporting a wide band of 100 MHz to a carrier in an unlicensed frequency band.

"New SID proposal: Study on New Radio Access Technology", RP-160671, NTT docomo, 3GPP TSG RAN Meeting # 71, Goteborg, Sweden, 7th-10th March, 2016.

"Revised SID on NR-based Access to Unlicensed Spectrum", RP-171601, Qualcomm Incorporated, 3GPP TSG RAN Meeting # 77, Sapporo, Japan, 11th-14th September, 2017.

  In some countries of the world, it is necessary to apply Listen-Before-Talk (LBT) in unlicensed frequency bands. Carrier sense is performed before transmission starts, and transmission within a predetermined time length is enabled only when it is confirmed by carrier sense that resources (channels, frequency bands) are not applied to other nearby systems. The mechanism is LBT.

The present invention realizes the application of NR while applying LBT in unlicensed frequency bands.
The present invention relates to a terminal device capable of performing wideband communication efficiently, a communication method used for the terminal device, a base station device capable of performing wideband communication efficiently, and communication used for the base station device. Provide a way.

(1) The first aspect of the present invention provides a DCI used for PDSCH scheduling.
A terminal device for receiving a format, comprising: a receiving unit for receiving the DCI format including an identifier indicating an uplink frequency band used for feedback of HARQ-ACK for the PDSCH; and an RF unit for the uplink frequency band. And a transmitting unit that transmits the HARQ-ACK in the re-adjusted uplink frequency band when receiving an instruction to trigger transmission of the HARQ-ACK feedback from the base station device. It is characterized by having.

  (2) Further, in the first aspect of the present invention, the transmitting unit may readjust the RF unit to the uplink frequency band while the receiving unit is receiving the PDSCH. It is characterized by starting.

  (3) A second aspect of the present invention is a base station apparatus for transmitting a DCI format used for PDSCH scheduling, wherein an uplink frequency band used for HARQ-ACK feedback on the PDSCH is provided. And a transmitting unit that transmits the DCI format including an identifier indicating the HARQ-ACK feedback to the terminal device 1, wherein the HARQ-ACK is transmitted in an uplink frequency band indicated by the identifier. And a receiving unit for receiving ACK.

  (4) A third aspect of the present invention is a communication method used in a terminal device that receives a DCI format used for PDSCH scheduling, and is used for uplink HARQ-ACK feedback for the PDSCH. Receiving the DCI format including an identifier indicating a link frequency band, re-adjusting an RF unit to the uplink frequency band, and instructing the base station apparatus to transmit the HARQ-ACK feedback. And receiving the HARQ-ACK in the readjusted uplink frequency band.

  (5) Further, a third aspect of the present invention is characterized in that while the PDSCH is being received, re-adjustment of an RF unit to the uplink frequency band is started.

  (6) A fourth aspect of the present invention is a communication method used in a base station apparatus that transmits a DCI format used for PDSCH scheduling, and is used for feedback of HARQ-ACK for the PDSCH. Transmitting the DCI format including an identifier indicating an uplink frequency band; and, when triggering transmission of the HARQ-ACK feedback to the terminal device 1, the uplink frequency band indicated by the identifier. And receiving the HARQ-ACK.

  According to the present invention, the terminal device can efficiently perform broadband communication. Further, the base station device can efficiently perform broadband communication.

FIG. 1 is a conceptual diagram of a wireless communication system according to one aspect of the present embodiment. It is an example which shows the structure of the radio | wireless frame which concerns on one aspect of this embodiment, a sub-frame, and a slot. It is a figure showing the example of composition of the slot and the mini slot concerning one mode of this embodiment. FIG. 4 is a diagram illustrating an example of control resource set mapping according to an aspect of the present embodiment. FIG. 5 is a diagram illustrating an example of a resource element included in a slot according to an aspect of the present embodiment. FIG. 3 is a diagram illustrating an example of a configuration of one REG according to an aspect of the present embodiment. FIG. 3 is a diagram illustrating a configuration example of a CCE according to an aspect of the present embodiment. FIG. 11 is a diagram illustrating an example of a relationship between the number of REGs configuring a REG group and a method of mapping PDCCH candidates according to an aspect of the present embodiment. FIG. 9 is a diagram illustrating an example of mapping of REGs configuring a CCE according to an aspect of the present embodiment. FIG. 1 is a schematic block diagram illustrating a configuration of a terminal device 1 of the present embodiment. FIG. 2 is a schematic block diagram illustrating a configuration of a base station device 3 according to the present embodiment. It is a figure showing an example of the 1st initial connection procedure (4-step contention based RACH procedure) concerning one mode of this embodiment. It is a figure showing an example of a PDCCH candidate monitored by terminal unit 1 concerning one mode of this embodiment. FIG. 14 is a diagram illustrating an example of Bandwidth adaptation according to an aspect of the present embodiment. FIG. 15 is a diagram illustrating an example of a configuration of UL BWP for each LBT subband in the embodiment of the present invention. FIG. 16 is a diagram illustrating an example of UL BWP switching according to the embodiment of the present invention. FIG. 17 is a diagram illustrating an example of the configuration of Carrier Aggregation in the embodiment of the present invention. FIG. 18 is a diagram illustrating an example of Cell switching in the embodiment of the present invention. FIG. 19 is a diagram illustrating an example of a procedure according to the embodiment of the present invention. FIG. 20 is a diagram showing an example of a procedure in the embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is a conceptual diagram of a wireless communication system according to one aspect of the present embodiment. In FIG. 1, the wireless communication system includes terminal devices 1A to 1C and a base station device 3 (gNB). Hereinafter, the terminal devices 1A to 1C are also referred to as terminal devices 1 (UE).

  Hereinafter, various wireless parameters related to communication between the terminal device 1 and the base station device 3 will be described. Here, at least a part of the radio parameters (for example, subcarrier spacing (SCS)) is also referred to as Numerology. The radio parameters include a subcarrier interval, an OFDM symbol length, a subframe length, a slot length, and at least a part of a minislot length.

The subcarrier interval used for wireless communication is determined by a communication method (for example, OFDM: Orthogonal Frequency) used for wireless communication between the terminal device 1 and the base station device 3.
Division Multiplex, OFDMA: Orthogonal Frequency Multiple Access, SC-FDMA: Single Carrier-Frequency Division Multi
This is one of the wireless parameters for i.e. Access, DFT-s-OFDM (Discrete Fourier Transform-spread-OFDM). For example, the subcarrier intervals are 15 kHz, 30 kHz, 60 kHz, and 120 kHz.

  FIG. 2 is an example illustrating a configuration of a radio frame, a subframe, and a slot according to an aspect of the present embodiment. In the example shown in FIG. 2, the length of the slot is 0.5 ms, the length of the subframe is 1 ms, and the length of the radio frame is 10 ms. A slot may be a unit of resource allocation in the time domain. For example, a slot may be a unit to which one transport block is mapped. For example, a transport block may be mapped to one slot. Here, the transport block is transmitted within a predetermined interval (for example, a transmission time interval (TTI)) defined by an upper layer (for example, Medium Access Control (MAC) and Radio Resource Control (RRC)). Data unit.

  For example, the slot length may be given by the number of OFDM symbols. For example, the number of OFDM symbols may be seven or fourteen. The slot length may be given based at least on the length of the OFDM symbol. OFDM symbol lengths may differ based at least on subcarrier spacing. Further, the length of the OFDM symbol may be given based at least on the number of points of a Fast Fourier Transform (FFT) used for generating the OFDM symbol. Further, the length of the OFDM symbol may include a length of a cyclic prefix (CP) added to the OFDM symbol. Here, the OFDM symbol may be referred to as a symbol. Also, in the communication between the terminal device 1 and the base station device 3, when a communication method other than OFDM is used (for example, when SC-FDMA or DFT-s-OFDM is used), the generated SC is used. -FDMA symbols and / or DFT-s-OFDM symbols are also referred to as OFDM symbols. Unless otherwise specified, OFDM includes SC-FDMA or DFT-s-OFDM.

  For example, slot lengths may be 0.125 ms, 0.25 ms, 0.5 ms, 1 ms. For example, when the subcarrier interval is 15 kHz, the length of the slot may be 1 ms. For example, when the subcarrier interval is 30 kHz, the slot length may be 0.5 ms. For example, if the subcarrier spacing is 120 kHz, the slot length may be 0.125 ms. For example, when the subcarrier interval is 15 kHz, the length of the slot may be 1 ms. For example, when the slot length is 0.125 ms, one subframe may be composed of eight slots. For example, when the length of the slot is 0.25 ms, one subframe may be composed of four slots. For example, when the length of the slot is 0.5 ms, one subframe may be composed of two slots. For example, when the length of the slot is 1 ms, one subframe may be composed of one slot.

  Here, OFDM includes a multicarrier communication system to which waveform shaping (Pulse Shape), PAPR reduction, out-of-band radiation reduction, or filtering, and / or phase processing (for example, phase rotation or the like) is applied. The multi-carrier communication scheme may be a communication scheme for generating / transmitting a signal in which a plurality of subcarriers are multiplexed.

  A radio frame may be given by the number of subframes. The number of subframes for a radio frame may be, for example, 10. Radio frames may be given by the number of slots.

  FIG. 3 is a diagram illustrating a configuration example of a slot and a mini-slot according to an aspect of the present embodiment. Note that mini slots may be referred to as non-slots. In FIG. 3, the number of OFDM symbols constituting one slot is seven. The mini-slot may be configured by one or more OFDM symbols whose number is smaller than the number of the plurality of OFDM symbols forming the slot. Also, mini-slots may be shorter in length than slots. FIG. 3 shows minislot # 0 to minislot # 5 as an example of the configuration of the minislot. The mini-slot may be configured by one OFDM symbol as shown in mini-slot # 0. Further, the mini-slot may be configured by two OFDM symbols as shown in mini-slots # 1 to # 3. Also, a gap (time interval) may be inserted between two mini slots as indicated by mini slot # 1 and mini slot # 2. Further, as shown in mini-slot # 5, the mini-slot may be configured to straddle the boundary between slot # 0 and slot # 1. That is, the mini-slot may be configured to straddle the boundary of the slot. Here, the minislot is also called a subslot. Further, the mini-slot is also referred to as sTTI (transmission TTI: Transmission Time Interval). Also, in the following, a slot may be read as a mini slot. A minislot may be configured with the same number of OFDM symbols as a slot. The mini-slot may be configured with a larger number of OFDM symbols than the number of the plurality of OFDM symbols forming the slot. The length of the time domain of the minislot may be shorter than the length of the slot. The length of the time domain of the minislot may be shorter than the length of the subframe.

  Hereinafter, physical channels and physical signals according to various aspects of the present embodiment will be described.

In FIG. 1, in the uplink wireless communication from the terminal device 1 to the base station device 3, for example, the following uplink physical channel is used. The uplink physical channel is used by the physical layer to transmit and receive information output from the upper layer.
・ PUCCH (Physical Uplink Control Channel)
・ PUSCH (Physical Uplink Shared Channel)
・ PRACH (Physical Random Access Channel)

PUCCH is used for transmitting and receiving uplink control information (UCI: Uplink Control Information). The uplink control information includes channel state information (CSI: Channel State Information) of a downlink channel, and a scheduling request (SR: SR: used for requesting a PUSCH (UL-SCH: Uplink-Shared Channel) resource for initial transmission). Scheduling Request), downlink data (TB: Transport block, MAC PDU: Medium Access Control Protocol Data Unit, DL-SCH: Downlink-Shared Channel, PDSCH: Physical Shared)
HARQ-ACK (Hybrid Automatic Repeat request ACKnowledgment) for the CHANNEL. HARQ-ACK indicates ACK (acknowledgement) or NACK (negative-acknowledgement). HARQ-ACK is also referred to as HARQ feedback, HARQ information, HARQ control information, and ACK / NACK. PUCCH may use a plurality of formats (PUCCH format). Different signal processing may be applied for each format. The amount of information that can be transmitted may differ for each format. The type of transmittable uplink control information may be different for each format.

  The channel state information (CSI: Channel State Information) includes at least a channel quality indicator (CQI: Channel Quality Indicator). The channel state information may include a rank indicator (RI: Rank Indicator). The channel state information may include a precoder matrix indicator (PMI: Precoder Matrix Indicator). CQI is an index related to channel quality (propagation strength), and PMI is an index indicating a precoder. RI is an index indicating the transmission rank (or the number of transmission layers).

  PUSCH is used for transmitting and receiving uplink data (TB, MAC PDU, UL-SCH, PUSCH). The PUSCH may be used to transmit and receive HARQ-ACK and / or channel state information along with uplink data. Also, the PUSCH may be used to transmit / receive only channel state information or only HARQ-ACK and channel state information. PUSCH is used for transmitting and receiving the random access message 3.

  The PRACH is used to transmit and receive a random access preamble (random access message 1). The PRACH transmits an initial connection establishment procedure, a handover procedure, a connection re-establishment procedure, synchronization (timing adjustment) for transmission of uplink data, and a request for a PUSCH (UL-SCH) resource. Used to indicate. The random access preamble may be used to notify the base station device 3 of an index (random access preamble index) given from an upper layer of the terminal device 1.

  The random access preamble may be given by cyclically shifting the Zadoff-Chu sequence corresponding to the physical root sequence index u. The Zadoff-Chu sequence may be generated based on the physical root sequence index u. A plurality of random access preambles may be defined in one cell. The random access preamble may be specified based at least on the index of the random access preamble. Different random access preambles corresponding to different indexes of the random access preamble may correspond to different combinations of the physical root sequence index u and the cyclic shift. The physical root sequence index u and the cyclic shift (a value of the cyclic shift) may be given based at least on information included in the system information. The physical root sequence index u may be an index for identifying a sequence included in the random access preamble. The random access preamble may be specified based at least on the physical root sequence index u.

In FIG. 1, the following uplink physical signals are used in uplink wireless communication. The uplink physical signal may not be used for transmitting and receiving information output from the upper layer, but is used by the physical layer.
-Uplink reference signal (UL RS: Uplink Reference Signal)

In the present embodiment, at least the following two types of uplink reference signals may be used.
・ DMRS (Demodulation Reference Signal)
・ SRS (Sounding Reference Signal)

DMRS relates to transmission and reception of PUSCH and / or PUCCH. DMRS
Is multiplexed with PUSCH or PUCCH. The base station device 3 uses DMRS to perform propagation path correction of PUSCH or PUCCH. Hereinafter, transmitting the PUSCH and the DMRS together is simply referred to as transmitting the PUSCH. Hereinafter, transmitting the PUCCH and the DMRS together is simply referred to as transmitting the PUCCH. Hereinafter, receiving both the PUSCH and the DMRS is simply referred to as receiving the PUSCH. Hereinafter, receiving both the PUCCH and the DMRS is simply referred to as receiving the PUCCH.

  The SRS may not be related to the transmission and reception of the PUSCH or PUCCH. The base station device 3 may use the SRS for measuring the channel state. The SRS may be transmitted and received at the end of a subframe in an uplink slot or a predetermined number of OFDM symbols from the end.

In FIG. 1, the following downlink physical channel is used in downlink wireless communication from the base station device 3 to the terminal device 1. The downlink physical channel is used by the physical layer to transmit and receive information output from the upper layer.
・ PBCH (Physical Broadcast Channel)
・ PDCCH (Physical Downlink Control Channel)
・ PDSCH (Physical Downlink Shared Channel)

  The PBCH is used to broadcast a master information block (MIB: Master Information Block, BCH: Broadcast Channel) commonly used in the terminal device 1. The PBCH may be transmitted based on a predetermined transmission interval. For example, the PBCH may be transmitted at 80 ms intervals. The content of the information included in the PBCH may be updated every 80 ms. The PBCH may be configured with 288 subcarriers. The PBCH may be configured to include two, three, or four OFDM symbols. The MIB may include information related to an identifier (index) for the synchronization signal. The MIB may include information indicating a slot number in which the PBCH is transmitted, a subframe number, and at least a part of a radio frame number.

PDCCH (NR PDCCH) is downlink control information (DCI: Downlink).
Control Information) is used to transmit and receive. Downlink control information is also called DCI format. The downlink control information may include at least one of a downlink grant and an uplink grant. A downlink grant is also referred to as a downlink assignment or a downlink allocation. The downlink control information may include Unlicensed access common information. The Unlicensed access common information is control information regarding access, transmission and reception, etc. in a license-free frequency band. The Unlicensed access common information may be information on a downlink subframe configuration (Subframe configuration for Unlicensed Access). The downlink subframe configuration may be based on the position of the OFDM symbol occupied in the subframe in which the PDCCH including the downlink subframe configuration information is allocated and / or the PDCCH including the downlink subframe configuration information. Indicates the position of the OFDM symbol that is occupied in the next subframe of the subframe to be used. In the occupied OFDM symbol, transmission and reception of a downlink physical channel and a downlink physical signal are performed. The Unlicensed access common information may be information on an uplink subframe configuration (UL duration and offset). The uplink subframe configuration includes the position of the subframe where the uplink subframe starts based on the subframe in which the PDCCH including the information of the uplink subframe configuration is arranged, and the subframe of the uplink subframe. Indicates a number. The terminal device 1 is not required to receive the downlink physical channel and the downlink physical signal in the subframe indicated by the information of the uplink subframe configuration.

  For example, downlink control information including a downlink grant or an uplink grant is transmitted and received on a PDCCH including a C-RNTI (Cell-Radio Network Temporary Identifier). For example, the Unlicensed access common information is transmitted and received on the PDCCH including the CC-RNTI (Common Control-Radio Network Temporary Identifier).

  One downlink grant is used at least for scheduling one PDSCH in one serving cell. The downlink grant is used at least for scheduling PDSCH in the same slot as the slot in which the downlink grant was transmitted. The downlink grant may be used for scheduling the PDSCH in a slot different from the slot in which the downlink grant was transmitted.

  One uplink grant is used at least for scheduling one PUSCH in one serving cell.

  The downlink subframe configuration may be indicated as the Unlicensed access common information. The downlink subframe configuration indicates the configuration of the OFDM symbol occupied by the subframe. The terminal device 1 recognizes a downlink physical channel and an OFDM symbol used for transmitting a physical signal in the base station device 3 from the OFDM symbol occupied by the subframe indicated by the downlink subframe configuration. OFDM symbols occupied by the current subframe and / or the next subframe may be indicated. Here, the current subframe refers to a subframe in which the Unlicensed access common information including downlink subframe configuration information is received. For example, it is shown that 14 OFDM symbols are occupied in the next subframe. For example, it is shown that ten OFDM symbols are occupied in the next subframe. For example, it is shown that three OFDM symbols are occupied in the next subframe. For example, it is shown that 14 OFDM symbols are occupied in the current subframe. For example, it is shown that 11 OFDM symbols are occupied in the current subframe. For example, it is shown that six OFDM symbols are occupied in the current subframe. For example, it is shown that three OFDM symbols are occupied in the current subframe.

The Unlicensed access common information may be information on an uplink subframe configuration (UL duration and offset). The uplink subframe configuration includes the position of the subframe where the uplink subframe starts based on the subframe in which the PDCCH including the information of the uplink subframe configuration is arranged, and the subframe of the uplink subframe. Indicates a number. The terminal device 1 is not required to receive the downlink physical channel and the downlink physical signal in the subframe indicated by the information of the uplink subframe configuration. For example, the first subframe and one subframe from the reference subframe are shown, and the terminal device 1 transmits the downlink physical channel and the downlink physical signal in the first subframe from the reference subframe. Is not required to be received. For example, the first sub-frame and six sub-frames from the reference sub-frame are shown, and the terminal device 1 has the first sub-frame, the second sub-frame and the three sub-frames from the reference sub-frame. It is not required to receive a downlink physical channel and a downlink physical signal in the fourth subframe, the fourth subframe, the fifth subframe, and the sixth subframe. For example, the sixth subframe and three subframes from the reference subframe are shown, and the terminal device 1 displays the sixth subframe, the seventh subframe, and the eight subframes from the reference subframe. It is not required to receive a downlink physical channel and a downlink physical signal in the first subframe.

  In the terminal device 1, one or a plurality of control resource sets (CORESET) (control resource set) are set (configured) to search for the PDCCH. The terminal device 1 attempts to receive the PDCCH in the set control resource set. Details of the control resource set will be described later.

  PDSCH is used for transmitting and receiving downlink data (DL-SCH, PDSCH). The PDSCH is used at least for transmitting and receiving a random access message 2 (random access response). The PDSCH is used at least for transmitting and receiving system information including parameters used for initial access.

In FIG. 1, the following downlink physical signals are used in downlink wireless communication. The downlink physical signal may not be used for transmitting and receiving information output from the upper layer, but is used by the physical layer.
-Synchronization signal (SS: Synchronization signal)
-Downlink reference signal (DL RS: Downlink Reference Signal)

  The synchronization signal is used by the terminal device 1 to synchronize the downlink frequency domain and the time domain. The synchronization signal includes PSS (Primary Synchronization Signal) and SSS (Secondary Synchronization Signal).

  The downlink reference signal is used for the terminal device 1 to perform channel correction of the downlink physical channel. The downlink reference signal is used by the terminal device 1 to calculate downlink channel state information.

In this embodiment, at least the following types of downlink reference signals are used.
・ DMRS (DeModulation Reference Signal)

  DMRS corresponds to transmission and reception of PDCCH and / or PDSCH. DMRS is multiplexed on PDCCH or PDSCH. The terminal device 1 may use the PDCCH or the DMRS corresponding to the PDSCH in order to perform channel correction of the PDCCH or the PDSCH. Hereinafter, transmitting the PDCCH and the DMRS corresponding to the PDCCH together is simply referred to as transmitting the PDCCH. Hereinafter, the reception of the PDCCH and the DMRS corresponding to the PDCCH together is simply referred to as the reception of the PDCCH. Hereinafter, transmitting the PDSCH and the DMRS corresponding to the PDSCH together is referred to simply as transmitting the PDSCH. Hereinafter, the fact that the PDSCH and the DMRS corresponding to the PDSCH are received together is simply referred to as the PDSCH being received.

The DMRS may be an RS individually set in the terminal device 1. The DMRS sequence may be given based at least on parameters individually set in the terminal device 1. DMRS may be transmitted separately for PDCCH and / or PDSCH. D
The MRS may be an RS that is commonly set for a plurality of terminal devices 1. The DMRS sequence may be given irrespective of parameters individually set in the terminal device 1. For example, a DMRS sequence may be given based on at least a part of a slot number, a minislot number, and a cell ID (identity). The DMRS may be a PDCCH and / or an RS transmitted regardless of whether the PDSCH is being transmitted.

  The downlink physical channel and the downlink physical signal are also called a downlink signal. The uplink physical channel and the uplink physical signal are also called an uplink signal. The downlink physical channel and the uplink physical channel are collectively referred to as a physical channel. The downlink physical signal and the uplink physical signal are collectively referred to as a physical signal.

  BCH, UL-SCH and DL-SCH are transport channels. A channel used in a medium access control (MAC) layer is called a transport channel. A unit of the transport channel used in the MAC layer is also called a transport block or a MAC PDU. In the MAC layer, HARQ (Hybrid Automatic Repeat reQuest) is controlled for each transport block. The transport block is a unit of data that the MAC layer passes (deliver) to the physical layer. In the physical layer, transport blocks are mapped to codewords, and modulation processing is performed for each codeword.

  The base station device 3 and the terminal device 1 exchange (transmit and receive) signals in a higher layer. For example, in the radio resource control (RRC) layer, the base station apparatus 3 and the terminal apparatus 1 transmit / receive RRC signaling (RRC message: Radio Resource Control message, also referred to as RRC information: Radio Resource Control). May be. The base station device 3 and the terminal device 1 may transmit and receive MAC CE (Control Element) in the MAC layer. Here, the RRC signaling and / or the MAC CE are also referred to as a higher layer signal (higher layer signaling).

  PUSCH and PDSCH are used at least for transmitting and receiving RRC signaling and MAC CE. Here, the RRC signaling transmitted by the PDSCH from the base station device 3 may be a common signaling to a plurality of terminal devices 1 in the cell. Signaling common to a plurality of terminal devices 1 in a cell is also referred to as common RRC signaling. The RRC signaling transmitted by the PDSCH from the base station device 3 may be signaling (dedicated signaling or UE specific signaling) dedicated to a certain terminal device 1. Signaling dedicated to the terminal device 1 is also referred to as dedicated RRC signaling. The cell-specific parameter may be transmitted using common signaling for a plurality of terminal devices 1 in a cell or dedicated signaling for a certain terminal device 1. The UE-specific parameter may be transmitted to a certain terminal device 1 using dedicated signaling. A PDSCH including dedicated RRC signaling may be scheduled by a PDCCH in a control resource set. A PDSCH including common RRC signaling may be scheduled by a PDCCH in a control resource set.

BCCH (Broadcast Control Channel), CCCH (Common Control Channel) and DCCH (Dedicated)
Control CHaneel is a logical channel. For example, the BCCH is an upper layer channel used for transmitting MIB. The CCCH (Common Control Channel) is an upper layer channel used for transmitting and receiving common information in the plurality of terminal devices 1. Here, the CCCH is used, for example, for the terminal device 1 that is not connected to the RRC. The DCCH (Dedicated Control Channel) is an upper layer channel used for transmitting and receiving individual control information (dedicated control information) to and from the terminal device 1. Here, the DCCH is used, for example, for the terminal device 1 connected to the RRC.

  A BCCH in a logical channel may be mapped to a BCH, DL-SCH, or UL-SCH in a transport channel. A CCCH in a logical channel may be mapped to a DL-SCH or a UL-SCH in a transport channel. The DCCH in the logical channel may be mapped to the DL-SCH or the UL-SCH in the transport channel.

  The UL-SCH in the transport channel is mapped to the PUSCH in the physical channel. The DL-SCH in the transport channel is mapped to the PDSCH in the physical channel. The BCH in the transport channel is mapped to the PBCH in the physical channel.

  Hereinafter, the control resource set will be described.

  FIG. 4 is a diagram illustrating an example of mapping of a control resource set according to an aspect of the present embodiment. A control resource set may be a time-frequency domain to which one or more control channels may be mapped. The control resource set may be an area in which the terminal device 1 attempts to receive and / or detect the PDCCH (blind decoding (BD: Blind Decoding)). As shown in FIG. 4A, the control resource set may be configured by continuous resources (Localized resources) in the frequency domain. Further, as shown in FIG. 4B, the control resource set may be configured by discontinuous resources (distributed resources) in the frequency domain.

  In the frequency domain, the unit of mapping of the control resource set may be a resource block. The control resource set may be composed of a plurality of resource blocks. In the time domain, the unit of mapping of the control resource set may be an OFDM symbol. The control resource set may be composed of one, two, or three OFDM symbols.

  The frequency domain of the control resource set may be the same as the system bandwidth of the serving cell. Further, the frequency domain of the control resource set may be given based at least on the system bandwidth of the serving cell. The frequency domain of the control resource set may be provided based at least on higher layer signaling or system information. For example, the position of the resource block configuring the control resource set is reported from the base station apparatus 3 to the terminal apparatus 1 using signaling of an upper layer. For each control resource set, the position of the resource block configuring the control resource set is reported from the base station device 3 to the terminal device 1 using the signaling of the upper layer.

The time domain of the control resource set may be provided based at least on higher layer signaling or system information. For example, the number of OFDM symbols constituting the control resource set is reported from the base station device 3 to the terminal device 1 using the signaling of the upper layer. For example, the start position of the OFDM symbol constituting the control resource set is reported from the base station device 3 to the terminal device 1 using the signaling of the upper layer. For example, the end position of the OFDM symbol constituting the control resource set is reported from the base station device 3 to the terminal device 1 using the signaling of the upper layer. For example, the position of the subframe in which the control resource set is arranged is notified from the base station device 3 to the terminal device 1 using signaling of an upper layer. For example, the position of the slot in which the control resource set is allocated is notified from the base station device 3 to the terminal device 1 using signaling of an upper layer. For example, the cycle of the subframe in which the control resource set is arranged is notified from the base station apparatus 3 to the terminal apparatus 1 using signaling of an upper layer. For example, the cycle of the slot in which the control resource set is arranged is notified from the base station device 3 to the terminal device 1 using signaling of an upper layer.

  As the control resource set, one or both types of a common control resource set (Common CORESET) and a dedicated control resource set (Dedicated control resource set) (UE specific CORESET) may be used. The common control resource set may be a control resource set commonly set for a plurality of terminal devices 1. The common control resource set may be given based at least on a synchronization signal, MIB, first system information, second system information, common RRC signaling, dedicated RRC signaling, cell ID, and the like. For example, the position of the subframe in which the common control resource set is arranged may be given based at least on a synchronization signal, MIB, common RRC signaling, or the like. The dedicated control resource set may be a control resource set that is set to be used exclusively for the individual terminal device 1. A dedicated control resource set may be provided based at least on dedicated RRC signaling and / or the value of the C-RNTI.

  The control resource set may be a set of control channels (or control channel candidates) monitored by the terminal device 1. The control resource set may include a set of control channels (or control channel candidates) monitored by the terminal device 1. The control resource set may be configured to include one or a plurality of search areas (search space, SS: Search Space). One or a plurality of search areas (search space, SS: Search Space) may be configured (set) in the control resource set.

  The search area is configured to include one or a plurality of PDCCH candidates. The terminal device 1 receives a PDCCH candidate included in the search area and tries to receive the PDCCH. Here, the PDCCH candidate is also referred to as a blind detection candidate.

  The search area has two types: CSS (Common Search Space, common search area) and USS (UE-specific Search Space). The CSS may be a search area commonly set for a plurality of terminal devices 1. The USS may be a search area including a setting exclusively used for the individual terminal device 1. The CSS may be provided based at least on a synchronization signal, MIB, first system information, second system information, common RRC signaling, dedicated RRC signaling, cell ID, and the like. The USS may be provided based at least on dedicated RRC signaling and / or the value of the C-RNTI. The CSS may be a search area set in a common resource (control resource element) for a plurality of terminal devices 1. The USS may be a search area set in a resource (control resource element) for each individual terminal device 1.

The CSS is a type 0 PDCCH C for the DCI format scrambled by the SI-RNTI used for transmitting system information in the primary cell.
The SS and the type 1 PDCCH CSS for the DCI format scrambled by the RA-RNTI and the TC-RNTI used for the initial access may be used. As the CSS, a type of PDCCH CSS for a DCI format scrambled by CC-RNTI used for Unlicensed access may be used. The terminal device 1 can monitor PDCCH candidates in those search areas. The DCI format scrambled by the predetermined RNTI may be a DCI format to which a CRC (Cyclic Redundancy Check) scrambled by the predetermined RNTI is added.

  Note that the PDCCH and / or DCI included in the CSS does not include a Carrier Indicator Field (CIF) indicating which serving cell (or which component carrier) the PDCCH / DCI schedules the PDSCH or PUSCH for. You may.

  When carrier aggregation for performing communication (transmission and / or reception) by aggregating a plurality of serving cells and / or a plurality of component carriers for the terminal device 1 is set, a predetermined serving cell (a predetermined component carrier) is set. PDCCH and / or DCI included in the USS for the PDCCH / DCI includes a CIF indicating which serving cell and / or component carrier the PDSCH or PUSCH is scheduled for.

  When communication is performed with respect to the terminal device 1 using one serving cell and / or one component carrier, the PDCCH and / or DCI included in the USS includes any of the serving cells and / or Alternatively, the CIF indicating which component carrier PDSCH or PUSCH is scheduled may not be included.

  The common control resource set may include CSS. The common control resource set may include both CSS and USS. The dedicated control resource set may include USS. The dedicated control resource set may include CSS.

  In the common control resource set, a PDCCH including control information required for Unlicensed access (Unlicensed access common information) may be transmitted and received. In the common control resource set, the PDCCH including the resource allocation information of the PDSCH including the RMSI (Remaining Minimum System Information) may be transmitted and received. In the common control resource set, a PDCCH including PDSCH resource allocation information including a RAR (Random Access Response) may be transmitted and received. In the common control resource set, a PDCCH including control information indicating pre-emption resources may be transmitted and received. In the common control resource set, a PDCCH including control information indicating a slot format indicator may be transmitted and received. Note that a plurality of common control resource sets may be configured, and each common control resource set may be arranged in a different subframe. Note that a plurality of common control resource sets may be configured, and each common control resource set may be arranged in the same subframe. A plurality of common control resource sets may be configured, and different PDCCHs and different control information may be arranged in each common control resource set.

A plurality of dedicated control resource sets may be configured in a subframe. A plurality of dedicated control resource sets may be configured, and each dedicated control resource set may be arranged in the same subframe. A plurality of dedicated control resource sets may be configured, and each dedicated control resource set may be arranged in a different subframe.

  The physical resource of the search area is configured by a control channel configuration unit (CCE: Control Channel Element). The CCE is composed of a predetermined number of resource element groups (REGs). For example, a CCE may be composed of six REGs. The REG may be configured by one OFDM symbol of one PRB (Physical Resource Block). That is, the REG may be configured to include 12 resource elements (REs). PRB is also simply called RB (Resource Block).

  That is, the terminal device 1 can detect the PDCCH and / or DCI for the terminal device 1 by blindly detecting the PDCCH candidates included in the search area in the control resource set.

  The number of times of blind detection for one control resource set in one serving cell and / or one component carrier is determined based on the type of search area for PDCCH included in the control resource set, the type of aggregation level, and the number of PDCCH candidates. May be done. Here, the type of the search area may include at least one of CSS and / or USS and / or UGSS (UE Group SS) and / or GCSS (Group CSS). The type of the aggregation level indicates the maximum aggregation level supported for the CCEs constituting the search area, and at least one of {1, 2, 4, 8,..., X} (X is a predetermined value) It may be defined / set from one. The number of PDCCH candidates may indicate the number of PDCCH candidates for a certain aggregation level. That is, the number of PDCCH candidates may be defined / set for each of a plurality of aggregation levels. The UGSS may be a search area commonly assigned to one or a plurality of terminal devices 1. The GCSS may be a search area in which DCI including parameters related to CSS is mapped to one or a plurality of terminal devices 1. The aggregation level indicates an aggregation level of a predetermined number of CCEs, and is related to the total number of CCEs constituting one PDCCH and / or a search area.

  The size of the aggregation level may be associated with the coverage corresponding to the PDCCH and / or the search area or the size of the DCI included in the PDCCH and / or the search area (DCI format size, payload size).

  In addition, when the start position (start symbol) of a PDCCH symbol is set for one control resource set, and when more than one PDCCH in the control resource set can be detected in a predetermined period In, for the time region corresponding to each start symbol, the type of search region for PDCCH included in the control resource set, the type of aggregation level, and the number of PDCCH candidates may be respectively set. The type of search area, the type of aggregation level, and the number of PDCCH candidates for the PDCCH included in the control resource set may be set for each control resource set, or may include DCI and / or higher layer signals (RRC signaling). ) May be provided / set, or may be specified / set in advance by a specification. Note that the number of PDCCH candidates may be the number of PDCCH candidates in a predetermined period. Note that the predetermined period may be 1 millisecond. The predetermined period may be one microsecond. Further, the predetermined period may be a period of one slot. Further, the predetermined period may be a period of one OFDM symbol.

In addition, when the start position (start symbol) of the PDCCH symbol is more than one for one control resource set, that is, when there are a plurality of timings for blindly detecting (monitoring) the PDCCH in a predetermined period, For the time domain corresponding to each start symbol, the type of the search domain, the type of the aggregation level, and the number of PDCCH candidates for the PDCCH included in the control resource set may be respectively set. The type of search area, the type of aggregation level, and the number of PDCCH candidates for the PDCCH included in the control resource set may be set for each control resource set, or may be set via DCI and / or higher layer signals. It may be provided / set, or may be specified / set in advance by a specification.

  As a method of indicating the number of PDCCH candidates, the number of PDCCH candidates to be reduced from a predetermined number may be defined / set for each aggregation level.

  The terminal device 1 may transmit / notify the base station device 3 of capability information related to blind detection. The terminal device 1 may transmit / notify the number of PDCCH candidates that can be processed in one subframe to the base station device 3 as capability information on PDCCH. If the terminal device 1 can set more than a predetermined number of control resource sets for one or a plurality of serving cells / component carriers, the terminal device 1 transmits / notifies the base station device 3 of the capability information related to the blind detection. Good.

  If the terminal device 1 supports the first slot format and the second slot format, the terminal device 1 may transmit / notify the base station device 3 of the capability information related to the slot format.

  The terminal device 1 transmits capability information related to blind detection to the base station device 3 to the base station device 3 when more than a predetermined number of control resource sets can be set for a predetermined period of one or a plurality of serving cells / component carriers. You may be notified.

  In addition, the capability information related to the blind detection may include information indicating the maximum number of times of the blind detection in a predetermined period. Also, the capability information related to the blind detection may include information indicating that PDCCH candidates can be reduced. In addition, the capability information related to the blind detection may include information indicating the maximum number of control resource sets that can be blindly detected in a predetermined period. The maximum number of the control resource sets and the maximum number of serving cells and / or component carriers capable of monitoring the PDCCH may be set as individual parameters or may be set as common parameters. In addition, the capability information related to the blind detection may include information indicating the maximum number of control resource sets that can simultaneously perform the blind detection in a predetermined period.

  If the terminal device 1 does not support the capability of detecting (blind detection) a control resource set greater than a predetermined number in a predetermined period, the terminal device 1 transmits / notifies capability information related to the blind detection. It is not necessary. If the base station apparatus 3 does not receive the capability information related to the blind detection, the base station apparatus 3 may configure the control resource set so as not to exceed a predetermined number for the blind detection, and may transmit the PDCCH. .

The setting related to the control resource set includes a parameter indicating an index (ControlResourceSetId) for identifying the control resource set. The setting related to the control resource set may include a parameter indicating the start position (start symbol) of the PDCCH. Further, the setting related to the control resource set includes a parameter indicating a time resource area of the control resource set (the number of OFDM symbols constituting the control resource set and / or a position of a subframe in which the control resource set is arranged). You may. Further, the setting related to the control resource set may include a parameter indicating a frequency resource region of the control resource set (the number of resource blocks configuring the control resource set). The setting related to the control resource set may include a parameter indicating the type of mapping from the CCE to the REG. Further, the setting regarding the control resource set may include the REG bundle size. RRC signaling may be used for transmitting and receiving a message indicating a setting related to a control resource set. The SIB may be used for transmitting and receiving a message indicating a setting related to the control resource set. The MIB may be used for transmitting and receiving a message indicating a setting related to the control resource set.

  The setting related to the search area includes a parameter indicating an index for identifying the search area (search area index). The setting related to the search area includes a parameter indicating the index of the control resource set in which the search area is arranged. The setting related to the search area may include parameters indicating the cycle and offset of the slot in which the search area is arranged. The setting regarding the search area may include a parameter indicating the number of slots in which the search areas are continuously arranged. The setting related to the search area may include a parameter indicating an OFDM symbol in a slot for monitoring a PDCCH candidate. The setting related to the search area may include a parameter indicating the number of PDCCH candidates to be monitored for each CCE aggregation level. The setting related to the search area may include a parameter indicating the DCI format in which monitoring is performed. The setting relating to the search area may include a parameter indicating the type of the search area (CSS or USS). RRC signaling may be used for transmitting and receiving a message indicating a setting related to a search area. The SIB may be used for transmitting and receiving a message indicating the setting regarding the search area. The MIB may be used for transmitting and receiving a message indicating the setting regarding the search area.

  Hereinafter, the unit of the physical resource according to the present embodiment will be described.

FIG. 5 is a diagram illustrating an example of a resource element included in a slot according to an aspect of the present embodiment. Here, the resource element is a resource defined by one OFDM symbol and one subcarrier. As shown in FIG. 5, a slot includes N _symb OFDM symbols. The number of subcarriers contained in the slot, the number N _RB of resource blocks included in the slot may be given by the product of number of subcarriers N ^RB _SC per resource block. Here, a resource block is a group of resource elements in the time domain and the frequency domain. The resource block may be used as a unit for resource allocation in the time domain and / or the frequency domain. For example, N ^RB _SC may be 12. N _symb may be the same as the number of OFDM symbols included in the subframe. N _symb may be the same as the number of OFDM symbols included in the slot. N _RB may be provided based on the cell bandwidth and subcarrier spacing. Further, the N _RB may be given based on an upper layer signal (for example, RRC signaling) transmitted from the base station device 3 or the like. Further, the N _RB may be given based on the description of the specification. A resource element is identified by an index k for a subcarrier and an index 1 for an OFDM symbol.

  FIG. 6 is a diagram illustrating an example of a configuration of one REG according to an aspect of the present embodiment. The REG may be configured by one OFDM symbol of one PRB. That is, the REG may be configured by 12 REs that are continuous in the frequency domain. Some of the plurality of REs constituting the REG may be REs to which no downlink control information is mapped. The REG may be configured to include an RE to which downlink control information is not mapped, or may be configured to not include an RE to which downlink control information is not mapped. The RE to which downlink control information is not mapped may be a RE to which a reference signal is mapped, an RE to which a channel other than a control channel is mapped, or a terminal device to which no control channel is mapped. 1 may be the RE assumed.

FIG. 7 is a diagram illustrating a configuration example of a CCE according to an aspect of the present embodiment. The CCE may be composed of six REGs. As shown in FIG. 7A, the CCE may be configured by REGs that are continuously mapped in the frequency domain (such mapping may be referred to as Localized mapping) (such mapping is referred to as non-mapping). -Interleaved CCE-to-REG mapping) (such mappings may be referred to as non-interleaved mapping). Note that not all REGs constituting the CCE need be continuous in the frequency domain. For example, when all of the plurality of resource blocks constituting the control resource set are not continuous in the frequency domain, even if the numbers assigned to the REGs are consecutive, each resource block constituting each consecutive number of REGs is Not continuous in the frequency domain. When the control resource set includes a plurality of OFDM symbols and a plurality of REGs configuring one CCE are arranged over a plurality of time sections (OFDM symbols), as shown in FIG. It may be constituted by a group of REGs that are continuously mapped in the region. As shown in FIG. 7C, the CCE may be configured by REGs that are mapped discontinuously in the frequency domain (such mapping may be referred to as Distributed mapping) (such mapping is referred to as “distributed mapping”). interleaved CCE-to-REG
(may be referred to as mapping) (such mapping may be referred to as interleaved mapping). REGs constituting a CCE using an interleaver may be discontinuously mapped to time-frequency domain resources. When the control resource set is composed of a plurality of OFDM symbols and a plurality of REGs constituting one CCE are arranged over a plurality of time sections (OFDM symbols), as shown in FIG. REGs of different time intervals (OFDM symbols) may be mixed and configured by non-continuously mapped REGs. As illustrated in FIG. 7E, the CCE may be configured by REGs that are distributed and mapped in groups of a plurality of REGs (a plurality of REGs mapped continuously in the frequency domain). As shown in FIG. 7 (f), the CCE may be configured by REGs that are distributed and mapped in groups of a plurality of REGs (a plurality of REGs mapped continuously in the time domain).

  The CCE may be configured to include one or a plurality of REG groups. REG groups are also referred to as REG bundles. The number of REGs that make up one REG group is referred to as Bundle size. For example, the bundle size of the REG may be any one of 1, 2, 3, and 6. In interleaved mapping, an interleaver may be applied for each REG bundle. The terminal device 1 may assume that the same precoder is applied to the REs in the REG group. The terminal device 1 can perform channel estimation on the assumption that the precoder applied to the REs in the REG group is the same. On the other hand, the terminal device 1 may assume that the precoders applied to the REs between the REG groups are not the same. In other words, the terminal device 1 does not need to assume that the precoder applied to the REs between the REG groups is the same. “Between REG groups” may be paraphrased as “between two different REG groups”. The terminal device 1 can perform channel estimation on the assumption that precoders applied to REs between REG groups are not the same. Details of the REG group will be described later.

The number of CCEs constituting a PDCCH candidate is determined by an aggregation level (AL: Aggregation).
Level). When one PDCCH candidate is configured by aggregation of a plurality of CCEs, one PDCCH candidate is configured by a plurality of CCEs with consecutive CCE numbers. Aggregation level set of PDCCH candidates of AL _X is referred to as the search area of the aggregation level AL _X. That is, the search area of the aggregation level AL _X is one aggregation level of AL _X or P
It may be configured to include DCCH candidates. In addition, the search area includes a plurality of aggregation level PDCs.
CH candidates may be included. For example, the CSS may include multiple aggregation level PDCCH candidates. For example, the USS may include multiple aggregation level PDCCH candidates. A set of aggregation levels of PDCCH candidates included in the CSS and a set of aggregation levels of PDCCH candidates included in the USS may be defined / set respectively.

  Hereinafter, the REG group will be described.

  The REG group may be used for channel estimation in the terminal device 1. For example, the terminal device 1 performs channel estimation for each REG group. This is based on the difficulty of performing channel estimation (eg, MMSE channel estimation, etc.) at the RE for reference signals to which different precoders are applied. Here, MMSE is an abbreviation for Minimum Mean Square Error.

  The accuracy of channel estimation varies at least based on the power allocated to the reference signal, the density of the RE used for the reference signal in the time-frequency domain, the environment of the radio channel, and the like. The accuracy of the channel estimation varies based at least on the time-frequency domain used for the channel estimation. In various aspects of the present embodiment, the REG group may be used as a parameter for setting a time-frequency region used for channel estimation.

  That is, the larger the REG group, the higher the gain of channel estimation accuracy. On the other hand, a small REG group means that one PDCCH candidate includes many REG groups. The fact that one REGCH group is included in one PDCCH candidate means that a transmission method (a precoder rotation, a precoder cycling, and the like) that acquires spatial diversity by applying a precoder individually to each REG group. ).

  One REG group may be configured by REGs that are continuous or close in the time domain and / or the frequency domain.

  The group of REGs in the time domain is suitable for improving channel estimation accuracy and / or reducing reference signals. For example, the number of REGs forming the REG group in the time domain may be one, two, three, or another value. Further, the number of REGs forming the REG group in the time domain may be given based at least on the number of OFDM symbols included in the control resource set. Further, the number of REGs forming the REG group in the time domain may be the same as the number of OFDM symbols included in the control resource set.

  The group of REGs in the frequency domain contributes to an improvement in channel estimation accuracy. For example, the number of REGs forming a group of REGs in the frequency domain may be two, three, or a multiple of at least two, or a multiple of at least three. Is also good. Further, the number of REGs forming the REG group in the frequency domain may be given based at least on the number of PRBs of the control resource set. Further, the number of REGs forming the REG group in the frequency domain may be the same as the number of PRBs included in the control resource set.

FIG. 8 is a diagram illustrating an example of REGs configuring PDCCH candidates and the number of REGs configuring a REG group according to an aspect of the present embodiment. In the example shown in FIG. 8A, PDCCH candidates are mapped to one OFDM symbol, and three REG groups including two REGs are formed. That is, in the example shown in FIG. 8A, one REG group is composed of two REGs. The number of REGs forming a group of REGs in the frequency domain may include a divisor of the number of PRBs mapped in the frequency direction. In the example illustrated in FIG. 8A, the number of REGs forming a group of REGs in the frequency domain may be 1, 2, 3, or 6.

  In the example shown in FIG. 8B, PDCCH candidates are mapped to two OFDM symbols, and three REG groups including two REGs are configured. In the example illustrated in FIG. 8B, the number of REGs forming a group of REGs in the frequency domain may be either one or three.

  The number of REGs forming a group of REGs in the frequency domain may be given based at least on the number of OFDM symbols to which PDCCH candidates are mapped. The number of REGs forming the REG group in the frequency domain may be individually set for the number of OFDM symbols to which PDCCH candidates are mapped. The number of REGs configuring the REG group in the frequency domain may be given based at least on a mapping method (mapping type) of the REGs configuring the CCE. The number of REGs constituting the REG group in the frequency domain may be individually set for the mapping method of the REGs constituting the CCE. The mapping method of the REGs constituting the CCE may be any one of the interleaved mapping and the non-interleaved mapping. The mapping method of the REGs constituting the CCE may be either a continuous mapping method or a discontinuous mapping method. The number of REGs forming a group of REGs in the frequency domain may be given based at least on the number of OFDM symbols to which one CCE is mapped. The number of REGs forming a group of REGs in the frequency domain may be set individually for the number of OFDM symbols to which one CCE is mapped.

  The number of REGs forming a group of REGs in the time domain may be given based at least on the number of OFDM symbols to which PDCCH candidates are mapped. The number of REGs forming the REG group in the time domain may be individually set for the number of OFDM symbols to which PDCCH candidates are mapped. The number of REGs forming a group of REGs in the time domain may be given based at least on the number of OFDM symbols to which one CCE is mapped. The number of REGs forming a group of REGs in the time domain may be set individually for the number of OFDM symbols to which one CCE is mapped.

  The group of REGs in the time domain is also suitable for reference signal reduction. When the REG group is configured as illustrated in FIG. 8B, the reference signal may be included in a front OFDM symbol and / or a rear OFDM symbol. For example, in the time domain, the first REG (leading REG) in the REG group may include a RE to which no downlink control information is mapped, and REGs other than the first REG in the REG group may have the downlink control information. It may not include REs that are not mapped.

FIG. 9 is a diagram illustrating an example of mapping of REGs configuring a CCE according to an aspect of the present embodiment. Here, a case where the number of OFDM symbols constituting the control resource set is three is shown. In FIG. 9, one CCE is composed of six REGs. In FIG. 9, the index m of the REG in the time domain is given a value of m = 0 to 2 (0, 1, 2) from the left. In FIG. 9, the index n of the REG in the frequency domain is given a value of n = 0 to 5 (0, 1, 2, 3, 4, 5) from the bottom. FIG. 9A shows an example in which REGs constituting a CCE are mapped to Time first. The Time first mapping maps the REG from the lower (small) index of the REG in the time domain to the higher (large) index of the REG in the time domain. When the index of the REG in the time domain reaches the maximum, the REG index in the frequency domain is changed. This is a mapping method in which one is added. In FIG. 9B, the REGs constituting the CCE are Frequen.
An example is shown that maps to cy first. The mapping of Frequency first maps the REG from the lower (small) index to the higher (large) index of the REG in the frequency domain. When the index of the REG in the frequency domain reaches the maximum, the index of the REG in the time domain is changed. This is a mapping method in which one is added. Here, to map the REG means to map the signal arranged in the REG.

  Hereinafter, a configuration example of the terminal device 1 according to an aspect of the present embodiment will be described.

FIG. 10 is a schematic block diagram illustrating a configuration of the terminal device 1 of the present embodiment. As illustrated, the terminal device 1 is configured to include a wireless transmission / reception unit 10 and an upper layer processing unit 14. The wireless transmission / reception unit 10 includes an antenna unit 11, an RF (Radio Frequency) unit 12, and a baseband unit 13. The upper layer processing unit 14 includes a medium access control layer processing unit 15 and a radio resource control layer processing unit 16. The wireless transmission / reception unit 10 is also referred to as a transmission unit, a reception unit, or a physical layer processing unit. The physical layer processing unit includes a decoding unit. The receiving unit of the terminal device 1 receives the PDCCH. The decoding unit of the terminal device 1 decodes the received PDCCH. More specifically, the decoding unit of the terminal device 1 performs the blind decoding process on the received signal of the resource corresponding to the USS PDCCH candidate. The decoding unit of the terminal device 1 performs a brand decoding process on the received signal of the resource corresponding to the PDCCH candidate of the CSS. The receiving unit of the terminal device 1 monitors PDCCH candidates in the control resource set. The receiving unit of the terminal device 1 receives the DCI format used for PDSCH scheduling. The receiving unit of the terminal device 1 monitors the PDCCH candidates and receives the DCI format. The receiving unit of the terminal device 1 transmits an uplink frequency band (UL Component carrier, UL) used for feedback of HARQ-ACK to PDSCH.
The DCI format including the identifier indicating the BWP is received. The transmitting unit of the terminal device 1 re-adjusts the RF unit 12 to the uplink frequency band indicated by the identifier indicating the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH, which is included in the received DCI format. . When receiving an instruction to trigger transmission of HARQ-ACK feedback from the base station device 3, the transmitting unit of the terminal device 1 transmits HARQ-ACK in the readjusted uplink frequency band. The transmitting unit of the terminal device 1 starts to readjust the RF unit 12 to the uplink frequency band specified by the base station device 3 while the receiving unit is receiving the PDSCH. While receiving the PDSCH scheduled by DCI format including the identifier indicating the uplink frequency band used for the feedback of the HARQ-ACK for the PDSCH, the transmission unit of the terminal device 1 performs the feedback of the HARQ-ACK for the PDSCH. The RF unit 12 starts to readjust the RF unit 12 to the uplink frequency band indicated by the identifier indicating the uplink frequency band that is used for (1).

  The upper layer processing unit 14 outputs uplink data (transport block) generated by a user operation or the like to the wireless transmission / reception unit 10. The upper layer processing unit 14 performs processing of a MAC layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC: Radio Link Control) layer, and an RRC layer.

  The medium access control layer processing unit 15 included in the upper layer processing unit 14 performs processing of the MAC layer.

The radio resource control layer processing unit 16 included in the upper layer processing unit 14 performs processing of the RRC layer. The radio resource control layer processing unit 16 manages various setting information / parameters of the own device. The radio resource control layer processing unit 16 sets various setting information / parameters based on the upper layer signal received from the base station device 3. That is, the radio resource control layer processing unit 16 sets various setting information / parameters based on information indicating various setting information / parameters received from the base station device 3. The radio resource control layer processing unit 16 sets a control resource set based on the RRC signaling received from the base station device 3. The radio resource control layer processing unit 16 sets a search area based on the RRC signaling received from the base station device 3. The radio resource control layer processing unit 16 sets a search area in the control resource set based on the RRC signaling received from the base station device 3. The radio resource control layer processing unit 16 sets various setting information / parameters for each uplink frequency band in which HARQ-ACK may be fed back. For example, various setting information / parameters for each uplink frequency band that may feed back HARQ-ACK set by the radio resource control layer processing unit 16 include a frequency domain position, a subcarrier interval, and a cyclic prefix length. , The number of symbols, and various setting information / parameters related to transmission power control.

  The radio resource control layer processing unit 16 performs setting of a plurality of uplink frequency bands based on the RRC signaling received from the base station device 3 as an uplink frequency band in which HARQ-ACK may be fed back. The transmission unit of the terminal device 1 performs the uplink used for the feedback of the HARQ-ACK for the PDSCH included in the received DCI format from the plurality of uplink frequency bands set by the radio resource control layer processing unit 16. The RF unit 12 is readjusted to the uplink frequency band indicated by the identifier indicating the frequency band. A plurality of uplink frequency bands may be managed as different cells, and different Cell indexes may be set as identifiers indicating the uplink frequency bands. A plurality of uplink frequency bands may be managed as different BWPs, and different BWP indexes may be set as identifiers indicating the uplink frequency bands.

  The wireless transmission / reception unit 10 performs physical layer processing such as modulation, demodulation, encoding, and decoding. The wireless transmission / reception unit 10 separates, demodulates, and decodes the signal received from the base station device 3 and outputs the decoded information to the upper layer processing unit 14. The wireless transmission / reception unit 10 generates a transmission signal by modulating and encoding data, and transmits the transmission signal to the base station device 3.

  The RF unit 12 converts the signal received via the antenna unit 11 into a baseband signal by quadrature demodulation (down conversion), and removes unnecessary frequency components. The RF unit 12 outputs the processed analog signal to the baseband unit.

  The baseband unit 13 converts an analog signal input from the RF unit 12 into a digital signal. The baseband unit 13 removes a portion corresponding to a CP (Cyclic Prefix) from the converted digital signal, performs a fast Fourier transform (FFT) on the signal from which the CP has been removed, and converts a signal in the frequency domain. Extract.

  The baseband unit 13 performs an inverse fast Fourier transform (IFFT) on the data to generate an OFDM symbol, adds a CP to the generated OFDM symbol, generates a baseband digital signal, and generates a baseband digital signal. The band digital signal is converted into an analog signal. The baseband unit 13 outputs the converted analog signal to the RF unit 12.

  The RF unit 12 removes extra frequency components from the analog signal input from the baseband unit 13 using a low-pass filter, up-converts the analog signal to a carrier frequency, and transmits the analog signal via the antenna unit 11. I do. Further, the RF unit 12 amplifies the power. Further, the RF unit 12 may have a function of controlling transmission power. The RF unit 12 is also called a transmission power control unit. The RF unit 12 re-adjusts an uplink frequency band for transmitting a signal based on an instruction from the transmission unit of the terminal device 1.

  Hereinafter, a configuration example of the base station device 3 according to an aspect of the present embodiment will be described.

  FIG. 11 is a schematic block diagram illustrating a configuration of the base station device 3 of the present embodiment. As illustrated, the base station device 3 is configured to include a radio transmission / reception unit 30 and an upper layer processing unit 34. The wireless transmission / reception unit 30 includes an antenna unit 31, an RF unit 32, and a baseband unit 33. The upper layer processing unit 34 includes a medium access control layer processing unit 35 and a radio resource control layer processing unit 36. The wireless transmitting / receiving unit 30 is also referred to as a transmitting unit, a receiving unit, or a physical layer processing unit.

  The upper layer processing unit 34 performs processing of the MAC layer, PDCP layer, RLC layer, and RRC layer.

  The medium access control layer processing unit 35 included in the upper layer processing unit 34 performs processing of the MAC layer.

  The radio resource control layer processing unit 36 included in the upper layer processing unit 34 performs processing of the RRC layer. The radio resource control layer processing unit 36 generates downlink data (transport block), system information, an RRC message (RRC signaling), a MAC CE, and the like arranged on the PDSCH, or obtains the information from an upper node, and obtains the radio transmission / reception unit. Output to 30. Further, the radio resource control layer processing unit 36 manages various setting information / parameters of each terminal device 1. The radio resource control layer processing unit 36 may set various setting information / parameters for each of the terminal devices 1 via a signal of an upper layer. That is, the radio resource control layer processing unit 36 transmits / reports information indicating various setting information / parameters.

  The radio resource control layer processing unit 36 sets and transmits various setting information / parameters for each uplink frequency band that may feed back HARQ-ACK. For example, various setting information / parameters for each uplink frequency band that may feed back HARQ-ACK set by the radio resource control layer processing unit 36 include a frequency domain position, a subcarrier interval, and a cyclic prefix length. , The number of symbols, and various setting information / parameters related to transmission power control.

  The radio resource control layer processing unit 36 sets a plurality of uplink frequency bands for the terminal device 1 as an uplink frequency band in which HARQ-ACK may be fed back. The receiving unit of the base station device 3 selects, from among the plurality of uplink frequency bands set by the radio resource control layer processing unit 36, the uplink used for the feedback of the HARQ-ACK to the PDSCH included in the transmitted DCI format. HARQ-ACK is received in the uplink frequency band indicated by the identifier indicating the link frequency band. A plurality of uplink frequency bands may be managed as different cells, and different Cell indexes may be set as identifiers indicating the uplink frequency bands. A plurality of uplink frequency bands may be managed as different BWPs, and different BWP indexes may be set as identifiers indicating the uplink frequency bands.

The function of the wireless transmitting / receiving unit 30 has the same function as that of the wireless transmitting / receiving unit 10. The wireless transmission / reception unit 30 grasps an SS (Search space: search area) configured in the terminal device 1. The wireless transmission / reception unit 30 includes an SS grasping unit, and the SS grasping unit grasps the SS configured in the terminal device 1. The SS grasping unit grasps one or more PDCCH candidates in the control resource set, which are configured as a search space of the terminal device. The SS grasping unit grasps PDCCH candidates (the number of PDCCH candidates and the numbers of PDCCH candidates) configured in the dedicated control resource set of the terminal device 1. The SS grasping unit grasps PDCCH candidates (the number of PDCCH candidates and the numbers of PDCCH candidates) configured in the common control resource set. The SS grasping unit grasps PDCCH candidates (the number of PDCCH candidates and the numbers of PDCCH candidates) configured in a control resource set for each LBT subband in the Bandwidth part. The transmitting unit of the radio transmitting / receiving unit 30 transmits the PDCCH using the PDCCH candidate.

  The transmitting unit of the base station device 3 transmits a DCI format used for PDSCH scheduling. The transmitting unit of the base station device 3 transmits a DCI format including an identifier indicating an uplink frequency band used for feedback of HARQ-ACK to PDSCH. The transmitting unit of the base station device 3 transmits information that triggers transmission of HARQ-ACK feedback to the terminal device 1.

  The transmission unit (transmission processing unit) of the radio transmission / reception unit 30 of the base station device 3 may transmit the PDCCH including the CC-RNTI. The transmission unit (transmission processing unit) of the wireless transmission / reception unit 30 of the base station device 3 may transmit the PDCCH including the Unlicensed access common information in the control resource set for each LBT subband in the Bandwidth part. The transmission unit (transmission processing unit) of the radio transmission / reception unit 30 of the base station device 3 transmits the PDCCH including the Unlicensed access common information (control information indicating the configuration of the LBT subband subframe) in the control resource set for each LBT subband. You may.

  The radio resource control layer processing unit 36 may be configured (or may be configured) by using a plurality of resource blocks in the corresponding LBT subband for each control resource set configured in the bandwidth part.

  Each of the units denoted by reference numerals 10 to 16 included in the terminal device 1 may be configured as a circuit. Each of the units denoted by reference numerals 30 to 36 included in the base station device 3 may be configured as a circuit. The terminal device 1 may include at least a memory and the circuit. The base station device 3 may include at least a memory and the circuit. In the terminal device 1, each circuit may have a memory, or may have a memory separately from the circuit. In the base station device 3, each circuit may have a memory, or may have a memory separately from the circuit.

  Hereinafter, an example of the procedure of the initial connection according to the present embodiment will be described.

  The base station device 3 includes a communicable range (or a communication area) controlled by the base station device 3. The communicable range is divided into one or a plurality of cells (or serving cells, subcells, beams, etc.), and communication with the terminal device 1 can be managed for each cell. On the other hand, the terminal device 1 selects at least one cell from a plurality of cells and attempts to establish a connection with the base station device 3. Here, the first state in which the connection between the terminal device 1 and at least one cell of the base station device 3 is established is also referred to as RRC connection (RRC Connection). The second state in which the terminal device 1 has not established a connection with any cell of the base station device 3 is also referred to as RRC idle. Further, the third state in which the connection between the terminal device 1 and at least one cell of the base station device 3 is established, but some functions are restricted between the terminal device 1 and the base station device 3 is as follows. Also referred to as RRC suspended. RRC suspension is also referred to as RRC inactive.

  The RRC idle terminal device 1 may attempt to establish a connection with at least one cell of the base station device 3. Here, the cell to which the terminal device 1 attempts to connect is also called a target cell. FIG. 12 is a diagram illustrating an example of a first initial connection procedure (4-step contention based RACH procedure) according to an aspect of the present embodiment. The first initial connection procedure is configured to include at least a part of steps 5101 to 5104.

  Step 5101 is a step in which the terminal device 1 requests a response for initial connection to the target cell via the physical channel. Alternatively, step 5101 is a step in which the terminal device 1 performs the first transmission to the target cell via the physical channel. Here, the physical channel may be, for example, a PRACH. The physical channel may be a channel exclusively used to request a response for an initial connection. The message transmitted from the terminal device 1 via the physical channel in Step 5101 is also referred to as a random access message 1. The signal of the random access message 1 may be generated based on a random access preamble index u given from an upper layer of the terminal device 1.

  The terminal device 1 performs downlink time-frequency synchronization before performing step 5101. In the first state, a synchronization signal is used for the terminal device 1 to perform downlink time-frequency synchronization.

  The synchronization signal may be transmitted including the ID of the target cell (cell ID). The synchronization signal may be transmitted including a sequence generated based at least on the cell ID. The fact that the synchronization signal includes the cell ID may mean that a sequence of the synchronization signal is given based on the cell ID. The synchronization signal may be transmitted by applying a beam (or a precoder).

  The beam exhibits a phenomenon that the antenna gain varies depending on the direction. The beam may be provided based at least on the directivity of the antenna. Also, the beam may be provided at least based on a phase conversion of the carrier signal. Also, the beam may be provided by applying a precoder.

  The terminal device 1 receives the PBCH transmitted from the target cell. The PBCH may be transmitted including an important information block (MIB: Master Information Block, EIB: Essential Information Block) including important system information used for the terminal device 1 to connect to the target cell. The important information block is system information. The important information block may include information on the number of the radio frame. The important information block may include information on a position in a superframe composed of a plurality of radio frames (for example, information indicating at least a part of a system frame number (SFN: System Frame Number) in the superframe). Further, the PBCH may include an index of a synchronization signal. The PBCH may include information related to receiving the PDCCH. The important information block may be mapped to the BCH in the transport channel. The important information block may be mapped to the BCCH in the logical channel.

  The information related to the reception of the PDCCH may include information indicating a control resource set. The information indicating the control resource set may include information on the number and location of PRBs to which the control resource set is mapped. The information indicating the control resource set may include information indicating the mapping of the control resource set. The information indicating the control resource set may include information related to the number of OFDM symbols to which the control resource set is mapped. The information indicating the control resource set may include information indicating a period (periodicity) of a slot to which the control resource set is mapped. The information indicating the control resource set may include information indicating a position in a time domain of a subframe or a slot in which the control resource set is arranged. The terminal device 1 can attempt to receive the PDCCH based at least on the information indicating the control resource set included in the PBCH.

The information related to the reception of the PDCCH may include information related to an ID indicating a destination of the PDCCH. The ID indicating the destination of the PDCCH may be an ID used for scrambling a CRC bit added to the PDCCH. The ID indicating the destination of the PDCCH is also called RNTI (Radio Network Temporary Identifier). The information related to the reception of the PDCCH may include information related to an ID used for scrambling a CRC bit added to the PDCCH. The terminal device 1 can attempt to receive the PDCCH based at least on the information related to the ID included in the PBCH.

  RNTI is SI-RNTI (System Information-RNTI), P-RNTI (Paging-RNTI), C-RNTI (Common-RNTI), Temporary C-RNTI (TC-RNTI), RA-RNTI (Random Access-RNTI). , CC-RNTI (Common Control-RNTI) and INT-RNTI (Interruption-RNTI). The SI-RNTI is used at least for scheduling of a PDSCH transmitted including system information. The P-RNTI is used at least for scheduling of the PDSCH transmitted including paging information and / or information such as a change notification of system information. The C-RNTI is used at least for scheduling user data for the terminal device 1 connected to the RRC. Temporary C-RNTI is used at least for scheduling the random access message 4. The Temporary C-RNTI is used at least to schedule a PDSCH that includes data mapped to a CCCH on a logical channel. RA-RNTI is used at least for scheduling of random access message 2. The CC-RNTI is used at least for transmitting and receiving control information of Unlicensed access. The INT-RNTI is used at least to indicate Pre-emption in the downlink.

  A common control resource set in which a PDSCH including PDSCH resource allocation information used for transmission and reception of system information (RMSI: Remaining Minimum System Information, OSI: Other System Information) may be arranged in association with a synchronization signal. . The common control resource set may be arranged in a subframe that is the same as or close to the time domain in which the synchronization signal is arranged.

  The information related to the reception of the PDCCH may include information on the aggregation level of the search area included in the control resource set. The terminal device 1 can specify the aggregation level of the PDCCH candidate to be tried to receive and determine the search area based on at least the information on the aggregation level of the search area included in the control resource set included in the PBCH. The information related to PDCCH reception may include information on the number of PDCCH candidates in the search area. Information related to PDCCH reception may include information on the number of PDCCH candidates for each aggregation level of the search area.

  The information related to the reception of the PDCCH may include information related to the REG group (REG bundle size). The information related to the reception of the PDCCH may include information indicating the number of REGs forming the REG group in the frequency domain. The information related to the reception of the PDCCH may include information indicating the number of REGs forming a group of REGs in the time domain.

  The reference signal corresponding to the control resource set may correspond to a plurality of PDCCH candidates included in the control resource set. The reference signal corresponding to the control resource set may be used for demodulation of a plurality of PDCCHs included in the control resource set.

The base station device 3 can transmit a PBCH including information related to the reception of the PDCCH and instruct the terminal device 1 to monitor the common control resource set. The terminal device 1 performs monitoring of the common control resource set based at least on detecting information related to the reception of the PDCCH included in the PBCH. The common control resource set is used at least for scheduling of the first system information (RMSI, OSI). The first system information may include important system information for the terminal device 1 to connect to the target cell. The first system information may include information on various downlink settings. The first system information may include information on various settings of the PRACH. The first system information may include information on various uplink settings. The first system information may include signal waveform information (OFDM or DFT-s-OFDM) set for random access message 3 transmission. The first system information may include at least a part of the system information other than the information included in the MIB.

The first system information may be mapped to a BCH on a transport channel. The first system information may be mapped to a BCCH in a logical channel. The first system information is SIB1 (System Information Block).
Type 1) may be included at least. The first system information may include at least SIB2 (System Information Block type 2). The common control resource set may be used for scheduling the random access message 2. Note that SIB1 may include information related to measurement necessary for making an RRC connection. In addition, the SIB 2 may include information about a channel that is common and / or shared between a plurality of terminal devices 1 in a cell. The MIB may include information indicating a frequency resource constituting the Bandwidth part. The system information SIB (SIB1) may include information indicating a frequency resource that configures the bandwidth part.

  The terminal device 1 may monitor the PDCCH based at least on information related to the reception of the PDCCH. The terminal device 1 may monitor the PDCCH based at least on information related to the REG group. The terminal device 1 may assume a setting applied for monitoring the PDCCH based at least on information related to the reception of the PDCCH.

  The base station device 3 can transmit the MIB and / or the first system information and instruct the terminal device 1 to monitor the common control resource set. The first system information may include information related to the reception of the PDCCH. The terminal device 1 may monitor the common control resource set based at least on the information related to the reception of the PDCCH included in the MIB and / or the first system information. The common control resource set may be used to schedule a PDSCH including paging information and / or information for a change notification of system information.

  Step 5102 is a step in which the base station device 3 makes a response to the random access message 1 to the terminal device 1. The response is also called a random access message 2. Random access message 2 may be sent via PDSCH. The PDSCH including the random access message 2 is scheduled by the PDCCH. CRC bits included in the PDCCH may be scrambled by RA-RNTI. The random access message 2 may be transmitted including a special uplink grant. The special uplink grant is also called a random access response grant. The special uplink grant may be included in the PDSCH including the random access message 2. The random access response grant may include at least Temporary C-RNTI.

  The base station device 3 can transmit the MIB, the first system information, and / or the second system information, and can instruct the terminal device 1 to monitor the common control resource set. The second system information may include information related to receiving the PDCCH. The terminal device 1 monitors the common control resource set based at least on information related to the reception of the PDCCH included in the MIB, the first system information, and / or the second system information. CRC bits added to the PDCCH may be scrambled by Temporary C-RNTI. The common control resource set may be used for scheduling the random access message 2.

  The common control resource set is further based on at least the physical route index u included in the random access message 1 transmitted from the terminal device 1 and / or the resources (PRACH resources) used for transmitting the random access message 1. May be given. Here, the random access message 1 may correspond to monitoring of a control resource set. Also, the resource may indicate a time and / or frequency resource. The resource may be given by a resource block index and / or a slot (subframe) index. Monitoring of the common control resource set may be triggered by the random access message 1.

  Step 5103 is a step in which the terminal device 1 transmits an RRC connection request to the target cell. The request for the RRC connection is also called a random access message 3. The random access message 3 may be transmitted via the PUSCH scheduled by the random access response grant. The random access message 3 may include an ID used for identifying the terminal device 1. The ID may be an ID managed by an upper layer. The ID may be S-TMSI (SAE Temporary Mobile Subscriber Identity). The ID may be mapped to the CCCH in a logical channel.

  Step 5104 is a step in which the base station device 3 transmits a contention resolution message to the terminal device 1. The collision resolution message is also called a random access message 4. After transmitting the random access message 3, the terminal device 1 monitors the PDCCH for scheduling the PDSCH including the random access message 4. The random access message 4 may include a collision avoidance ID. Here, the collision avoidance ID is used to resolve a collision in which a plurality of terminal devices 1 transmit signals using the same radio resource. The collision avoidance ID is also referred to as UE contention resolution identity.

  In step 5104, the terminal device 1 that has transmitted the random access message 3 including the ID (for example, S-TMSI) used for identifying the terminal device 1 monitors the random access message 4 including the collision resolution message. If the collision avoidance ID included in the random access message 4 is equal to the ID used to identify the terminal device 1, the terminal device 1 considers that the collision resolution has been completed successfully, and sets the C-RNTI field to May be set to the value of Temporary C-RNTI. The terminal device 1 in which the value of Temporary C-RNTI is set in the C-RNTI field is regarded as having completed the RRC connection.

The control resource set for monitoring the PDCCH for scheduling the random access message 4 may be a common control resource set. The base station apparatus 3 can transmit the information related to the reception of the PDCCH in the random access message 2 and instruct the terminal apparatus 1 to monitor the common control resource set. The terminal device 1 monitors the PDCCH based at least on information related to the reception of the PDCCH included in the random access message 2.

  The terminal device 1 connected to the RRC can receive the dedicated RRC signaling mapped to the DCCH in the logical channel. The base station device 3 can transmit dedicated RRC signaling including information related to the reception of the PDCCH, and instruct the terminal device 1 to monitor the dedicated control resource set. The terminal device 1 performs monitoring of the PDCCH based at least on information related to the reception of the PDCCH included in the dedicated RRC signaling. In addition, the base station device 3 can transmit dedicated RRC signaling including information related to the reception of the PDCCH, and instruct the terminal device 1 to monitor the common control resource set. The terminal device 1 monitors the PDCCH including the CC-RNTI in the common control resource set.

  The base station device 3 can transmit a random access message 4 including information related to the reception of the PDCCH, and can instruct the terminal device 1 to monitor the dedicated control resource set. When the information related to the reception of the PDCCH is included in the random access message 4, the terminal device 1 may monitor the dedicated control resource set based at least on the information related to the reception of the PDCCH.

  The common control resource set may include not only one type but also a plurality of types. Depending on the application, a plurality of common control resource sets may be independently configured. For example, a common control resource set for transmitting and receiving PDCCH including CC-RNTI and a common control resource set for transmitting and receiving PDCCH including SI-RNTI may be configured independently. Each of the plurality of common control resource sets may be configured in a different LBT subband.

  FIG. 13 is a diagram illustrating an example of a PDCCH candidate monitored by the terminal device 1 according to an aspect of the present embodiment. FIG. 13A shows an example of a PDCCH candidate in a search area of a dedicated control resource set (Dedicated CORESET, UE-specific CORESET) set based on RRC signaling. FIG. 13A also illustrates an example of a USS PDCCH candidate set based on RRC signaling. In FIG. 13A, an example in which six PDCCH candidates at aggregation level 1, six PDCCH candidates at aggregation level 2, two PDCCH candidates at aggregation level 4, and two PDCCH candidates at aggregation level 8 are configured. Is shown. FIG. 13B shows an example of a PDCCH candidate in a search area of a common control resource set (Common Coreset). FIG. 13B also shows an example of a PDCCH candidate of the CSS. FIG. 13B shows an example in which four PDCCH candidates of aggregation level 4 and two PDCCH candidates of aggregation level 8 are configured.

FIG. 13C shows an example of arrangement of a control resource set and a search area. In Subframe #X, only a search area in an individual control resource set is arranged for a certain terminal device 1. In Subframe #X, the terminal device 1 monitors a total of 16 PDCCH candidates in the search area for the dedicated control resource set, as shown in FIG. In Subframe #Y, for a certain terminal device 1, a search area in an individual control resource set and a search area in a common control resource set are arranged. As shown in FIG. 13B, the terminal device 1 monitors a total of six PDCCH candidates in the search region for the common control resource set and a total of ten PDCCH candidates in the search region for the individual control resource set. Monitor. In Subframe #Z (third time section), only a common control resource set search area is arranged for a certain terminal device 1. In Subframe #Z, the terminal device 1 monitors a total of six PDCCH candidates in the search area for the common control resource set, as shown in FIG. The common control resource set of Subframe #Y and the common control resource set of Subframe #Z may be different types of common control resource sets.

  As shown in FIG. 13C, the individual control resource set and the common control resource set may be configured from different frequency resources. Although not shown in FIG. 13C, when a plurality of individual control resource sets are configured, each individual control resource set may be configured from a different frequency resource. Although not illustrated in FIG. 13C, when a plurality of common control resource sets are configured, each common control resource set may be configured from different frequency resources. Also, each control resource set may be composed of different time resources (OFDM symbols). The USS may be arranged in the common control resource set. The CSS may be arranged in the individual control resource set.

  A plurality of BWPs (BandWidth Parts) may be configured in the terminal device 1, and the common control resource set and the individual control resource set may be configured in different BWPs. BWP means a frequency bandwidth of a part of a carrier (cell), and is used to limit a frequency bandwidth used for communication by the terminal device 1 or used to support broadband communication.

  In the common control resource set, a PDCCH including information (Preemption indication) for indicating a free resource may be transmitted and received. In the common control resource set, a PDCCH including information for indicating a reserved resource may be transmitted and received. In the common control resource set, a PDCCH including information indicating a slot format configuration (SFI: Slot Format Indication) may be transmitted and received.

  An example of an operation related to an LBT (Listen-Before-Talk) according to the embodiment of the present invention will be described. LBT category 4 among a plurality of LBT categories will be described. First, the base station device 3 determines whether the channel (resource, frequency band, carrier) is idle (busy) during the first time. The base station device 3 selects a random value from a predetermined range as a backoff counter (random backoff). If the base station apparatus 3 determines that the channel is idle during the first time, it performs carrier sense at each sensing slot time to determine whether the channel is idle. When determining that the channel is idle in the sensing slot time, the base station device 3 decreases the value of the back-off counter and performs carrier sensing again in the next sensing slot time. When determining that the channel is busy in the sensing slot time, the base station device 3 returns to the process of determining whether the channel is idle during the first time.

  When it is determined that the channel is idle in a plurality of sensing slot times and the value of the back-off counter becomes zero, the base station apparatus 3 transmits a signal, schedules the terminal apparatus 1 (resource allocation), Start receiving signals from The base station device 3 starts access using the resources. When a communication error is confirmed (when a data error occurs) after the start of signal transmission / reception, the base station apparatus 3 sets an upper limit (Contention window) of a value generation range with respect to generation of a backoff counter in random backoff. size). If a communication error is not confirmed after the start of signal transmission / reception, the base station apparatus 3 sets the upper limit of a value generation range to an initial value for generation of a backoff counter in random backoff.

For example, LBT is performed for each frequency band of 20 MHz. For example, LBT carrier sensing is performed for each frequency band of 20 MHz. The unit of the frequency band of the carrier sense of the LBT is referred to as an LBT subband, an LBT grid, an LBT frequency bandwidth, and the like.

  Also, it is determined whether the channel (resource, frequency band, carrier) is idle (whether busy) for a certain period of time without using the back-off operation, and it is determined that the channel is idle. In this case, an LBT in which the base station device 3 starts accessing the terminal device 1 (starts signal transmission, starts scheduling, starts resource allocation) may be used. This type of LBT is referred to as LBT category 2.

  The operation of Bandwidth Adaptation (BA) in the embodiment of the present invention will be described. The base station device 3 adjusts the reception bandwidth and the transmission bandwidth of the terminal device 1 with the frequency bandwidth of the cell as the upper limit. When the activity of data transmission / reception is low, the reception bandwidth and the transmission bandwidth of the terminal device 1 may be set small to reduce power consumption. The frequency band adjusted in this way is a subset of the total frequency band of the cell, and is called Bandwidth Part (BWP). The change of the BWP may include at least a change of the setting of the RF unit 12 and / or a change of the setting of the baseband unit 13.

In the terminal device 1, one default downlink BWP (Default Downlink BWP) (Default DL BWP) may be set based on at least the RRC signaling. In the terminal device 1, one active downlink BWP (Active Downlink BWP) (Active DL BWP) may be set based on at least the RRC signaling. In the terminal device 1, based on at least the system information (SIB), one initial downlink BWP (Initial
Downlink BWP (Initial DL BWP) may be set. In the terminal device 1, one initial downlink BWP (Initial Downlink BWP) (Initial DL BWP) may be set based on at least the MIB. In the terminal device 1, at least one default uplink BWP (Default Uplink BWP) (Default) based on the RRC signaling.
UL BWP) may be set. In the terminal device 1, one active uplink BWP (Active UL BWP) may be set based on at least the RRC signaling. In the terminal device 1, one initial uplink BWP (Initial UL BWP) (Initial UL BWP) may be set based on at least the system information (SIB). In the terminal device 1, at least one Initial Uplink BWP (Initial UL BWP) may be set based on the MIB.

  In the terminal device 1, one or more downlink BWPs (Downlink BWPs) (DL BWPs) may be configured based on at least the RRC signaling. Further, in the terminal device 1, one or a plurality of downlink BWPs (Downlink BWPs) (DL BWPs) may be set for one serving cell based on at least the RRC signaling. In the terminal device 1, one or more uplink BWPs (Uplink BWPs) (UL BWPs) may be set based on at least the RRC signaling. In the terminal device 1, one or a plurality of uplink BWPs (Uplink BWPs) (UL BWPs) may be set for one serving cell based at least on RRC signaling.

As parameters relating to the setting of BWP (messages of RRC signaling), parameters indicating the position of the frequency domain and the frequency bandwidth (locationAndBandwidth)
h) may be used. A parameter (subcarrier Spacing) indicating a subcarrier interval may be used as a parameter related to BWP setting (RRC signaling message). A parameter (cyclicPrefix) indicating a cyclic prefix length may be used as a parameter related to the BWP setting (RRC signaling message). A parameter (bwp-Id) indicating a BWP index may be used as a parameter related to the BWP setting (RRC signaling message).

  FIG. 14 is a diagram illustrating an example of Bandwidth adaptation according to an aspect of the present embodiment. In the example illustrated in FIG. 14, DL BWP 511 and DL BWP 512 are set for a certain terminal device 1 in the serving cell 500. The DL BWP 511 is given by a frequency band between the resource block index 501 and the resource block index 502. Also, DL BWP 512 is given by a frequency band between resource block index 503 and resource block index 504. For example, the DL BWP 511 is set as the default downlink BWP or the initial downlink BWP.

  In FIG. 14, first, the DL BWP 511 is the Active DL BWP (active DL BWP). The terminal device 1 receives a signal in Active DL BWP. The terminal device 1 receives the PDCCH 521 in the DL BWP 511. The PDCCH 521 is transmitted and received using the frequency resources of the DL BWP 511, but is not necessarily transmitted and received using all the frequency resources of the DL BWP 511. Next, Active DL BWP is set based on the bandwidth width indicator field included in the DCI format included in the PDCCH 521. The DL BWP to be set to the active state among the DL BWPs configured in advance in the terminal device 1 is indicated by a bandwidth width indicator field. In FIG. 14, the bandwidth path indicator field included in PDCCH 521 indicates DL BWP 512 as Active DL BWP, and terminal device 1 sets DL BWP 512 as Active DL BWP. The terminal device 1 receives the downlink signal 522 (PDCCH, PDSCH) in the DL BWP 512. The downlink signal 522 (PDCCH, PDSCH) is transmitted / received using the frequency resources of the DL BWP 512, but is not necessarily transmitted / received using all the frequency resources of the DL BWP 512.

When the Active DL BWP is set to a DL BWP different from the Default DL BWP or the Initial DL BWP in the terminal device 1, a timer (BWP Inactivity Timer) may be started. Active DL
If the PDCCH including the resource allocation information is not received in BWP, the value of the timer is increased. When the timer value reaches a preset threshold, Active DL BWP is changed to Default DL BWP or Initial DL BWP.

In FIG. 14, an example of Bandwidth adaptation in which BWP switching is performed based on the bandwidth width indicator field of the DCI format has been described. Good. For example, BWP set based on MIB may be Bandwidth adaptation adjusted based on SIB. For example, BWP set based on MIB may be Bandwidth adaptation adjusted based on Dedicated RRC signaling. For example, BWP set based on SIB may be Bandwidth adaptation adjusted based on Dedicated RRC signaling. INDUSTRIAL APPLICABILITY The present invention can be applied to Bandwidth adaptation in which BWP in a frequency band larger than the LBT subband can be used.

  FIG. 15 is a diagram illustrating an example of a configuration of UL BWP for each LBT subband in the embodiment of the present invention. The configuration of the BWP set in the radio resource control layer processing unit 16 of the terminal device 1 and the radio resource control layer processing unit 36 of the base station device 3 will be described. Here, each UL BWP indicates an uplink frequency band that may be used for HARQ-ACK feedback. In TDD (unpaired spectrum), a certain common frequency band can be used as a downlink frequency band and an uplink frequency band at different times. Therefore, in FIG. 15, a DL BWP may be configured for each LBT subband, one DL BWP may be configured from a plurality of LBT subbands, and a common LBT subband is included in different DL BWP configurations. It may be. Further, UL BWP shown in FIG. 15 is a setting as an uplink frequency band that may be used for feedback of HARQ-ACK, and a UL BWP having a different configuration may be set for data transmission. .

In FIG. 15, five LBT subbands (LBT subband 0, LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband 4) are configured. In FIG. 15, five UL BWPs (UL BWP 0, UL BWP 1, UL BWP 2, UL BWP 3, and UL BWP 4) are configured. In the frequency domain, UL BWP 0 in LBT subband 0, UL BWP 1 in LBT subband 1, UL BWP 2 in LBT subband 2, UL BWP in LBT subband 3, UL BWP 4UB in SBB You. In FIG. 15, the terminal device 1 is UL BWP
0 is activated, and the RF unit 12 is adjusted to UL BWP 0. The base station device 3 determines that LBT subband 0 is idle (other systems and devices are not accessing (not transmitting a signal)).

  The base station apparatus 3 schedules the PDSCH to the terminal apparatus 1 using the frequency bands of LBT subband 0, LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband 4. The base station device 3 transmits the PDCCH to the terminal device 1 in at least one of the frequency bands of LBT subband 0, LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband 4. The base station apparatus 3 performs LBT in each frequency band of LBT subband 0, LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband 4, and confirms whether or not collision has occurred with another system. ing. The base station apparatus 3 transmits an instruction for triggering transmission of HARQ-ACK feedback to the terminal apparatus 1, and receives the HARQ-ACK feedback for the PDSCH in UL BWP 0.

FIG. 16 is a diagram illustrating an example of UL BWP switching according to the embodiment of the present invention. The configuration of the LBT subband and UL BWP is the same as that in FIG. The base station device 3 uses the frequency band of LBT subband 0, LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband 4 to schedule the PDSCH for the terminal device 1 using the frequency band of the LBT subband, and the LBT subband in the LBT subband. It detects that another system is transmitting a signal (colliding with another system) (accessing another system). The base station apparatus 3 transmits the DCI format (DL assignment) used for scheduling of the PDSCH and the DCI format including the identifier indicating the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH to the terminal apparatus 1. Send to The base station apparatus 3 sets the BWP index of UL BWP 1 as the identifier indicating the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH, and transmits the identifier to the terminal apparatus 1. For example, the base station apparatus 3 transmits the DCI format including the identifier indicating the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH using the PDCCH of the LBT subband 1.

  The terminal device 1 transmits the DCI format (DL assignment) used for PDSCH scheduling, including the identifier indicating the uplink frequency band used for HARQ-ACK feedback to the PDSCH, to the base station device 3. Receive from. In the terminal device 1, UL BWP 1 is indicated by an identifier indicating an uplink frequency band used for feedback of HARQ-ACK to PDSCH. The terminal device 1 re-adjusts the RF unit 12 to UL BWP 1. The terminal device 1 switches the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH from UL BWP 0 to UL BWP 1. The terminal device 1 re-adjusts the RF unit 12 to the UL BWP 1 while receiving the PDSCH scheduled by the DCI format including the identifier indicating the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH. Start to do.

  The base station device 3 transmits information that triggers transmission of HARQ-ACK feedback to the terminal device 1 after the time required for the terminal device 1 to readjust the RF unit 12 has elapsed. The terminal device 3 receives, from the base station device 3, information that triggers transmission of HARQ-ACK feedback after a time period necessary for readjustment of the RF unit 12 has elapsed. When the base station device 3 triggers transmission of HARQ-ACK feedback to the terminal device 1, the uplink frequency indicated by the identifier indicating the uplink frequency band used for HARQ-ACK feedback on the PDSCH HARQ-ACK is received in UL BWP 1 which is a band. When receiving an instruction to trigger transmission of HARQ-ACK feedback from the base station device 3, the terminal device 1 transmits HARQ-ACK in UL BWP 1, which is an uplink frequency band readjusted by the RF unit 12. Send.

FIG. 17 is a diagram illustrating an example of the configuration of Carrier Aggregation in the embodiment of the present invention. The configuration of Carrier Aggregation set in the radio resource control layer processing unit 16 of the terminal device 1 and the radio resource control layer processing unit 36 of the base station device 3 will be described. In Carrier Aggregation, a plurality of cells (element carriers) are collected and signals are transmitted and received simultaneously. The configuration of Carrier Aggregation configured for the terminal device 1 may not be the same for the downlink and the uplink. A cell that forms only a downlink frequency band is a carrier.
Aggregation may be used. Only a plurality of downlink frequency bands may be used collectively, and only a single uplink frequency band may be used at the same time.

  Here, each Cell includes an uplink frequency band that may be used for HARQ-ACK feedback. In TDD (paired spectrum), a certain common frequency band can be used as a downlink frequency band and an uplink frequency band at different times. In FIG. 17, while the PDSCH is simultaneously received in a plurality of cells, transmission of HARQ-ACK feedback is performed in a unit cell. FIG. 17 mainly shows which cell is active as an uplink frequency band that may be used for feedback of HARQ-ACK.

  In FIG. 17, five LBT subbands (LBT subband 0, LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband 4) are configured. In FIG. 17, five cells (Cell 0, Cell 1, Cell 2, Cell 3, and Cell 4) are configured. In the frequency domain, Cell 0 is contained in LBT subband 0, Cell 1 is contained in LBT subband 1, Cell 2 is contained in LBT subband 2, Cell 3 is contained in LBT subband 3, Cell is contained in LBT subband 4, and Cell 4 is contained in LBT subband 4. In FIG. 17, the terminal device 1 activates the configuration of Cell 0 as an uplink frequency band used for transmission of HARQ-ACK feedback, and adjusts the RF unit 12 to Cell 0. The base station device 3 determines that LBT subband 0 is idle (other systems and devices are not accessing (not transmitting a signal)).

The base station apparatus 3 schedules the PDSCH to the terminal apparatus 1 using the frequency bands of LBT subband 0, LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband 4. That is, the base station device 3 schedules the PDSCH to the terminal device 1 using the frequency bands of Cell 0, Cell 1, Cell 2, Cell 3, and Cell 4. For example, the base station device 3 includes the LBT subband 0, the LBT subband
1, the PDCCH is transmitted to the terminal device 1 in each of the frequency bands LBT subband 2, LBT subband 3, and LBT subband 4. For example, the base station device 3 transmits the PDCCH to the terminal device 1 in each of Cell 0, Cell 1, Cell 2, Cell 3, and Cell 4. The base station apparatus 3 performs LBT in each frequency band of LBT subband 0, LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband 4, and confirms whether or not collision has occurred with another system. ing. The base station apparatus 3 transmits an instruction to trigger transmission of HARQ-ACK feedback to the terminal apparatus 1, and receives the HARQ-ACK feedback for PDSCH in Cell 0.

FIG. 18 is a diagram illustrating an example of Cell switching in the embodiment of the present invention. Note that the configuration of Carrier Aggregation is the same as that of FIG. The base station device 3 includes LBT subband 0, LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband.
When the PDSCH is scheduled for the terminal device 1 using the frequency band of No. 4, another system is transmitting a signal in the LBT of the LBT subband 0 (colliding with the other system) (the other system is accessing the signal). Has been detected). The base station apparatus 3 transmits the DCI format (DL assignment) used for scheduling of the PDSCH and the DCI format including the identifier indicating the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH to the terminal apparatus 1. Send to The base station apparatus 3 sets the Cell index of Cell 1 as the identifier indicating the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH, and transmits the identifier to the terminal apparatus 1. For example, the base station apparatus 3 converts the DCI format including the identifier indicating the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH into the LBT subband 1 (Cell
It transmits using PDCCH of 1).

The terminal device 1 is a DCI format (DL assignment) used for PDSCH scheduling and includes a DCI format including an identifier indicating an uplink frequency band used for feedback of HARQ-ACK to the PDSCH.
t is received from the base station device 3. In the terminal device 1, Cell 1 is indicated by an identifier indicating an uplink frequency band used for feedback of HARQ-ACK to PDSCH. The terminal device 1 re-adjusts the RF unit 12 to Cell 1. The terminal device 1 switches the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH from Cell 0 to Cell 1. The terminal device 1 re-adjusts the RF unit 12 to the Cell 1 while receiving the PDSCH scheduled by the DCI format including the identifier indicating the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH. To start that.

  The base station device 3 transmits information that triggers transmission of HARQ-ACK feedback to the terminal device 1 after the time required for the terminal device 1 to readjust the RF unit 12 has elapsed. The terminal device 3 receives, from the base station device 3, information that triggers transmission of HARQ-ACK feedback after a time period necessary for readjustment of the RF unit 12 has elapsed. When the base station device 3 triggers transmission of HARQ-ACK feedback to the terminal device 1, the uplink frequency indicated by the identifier indicating the uplink frequency band used for HARQ-ACK feedback on the PDSCH HARQ-ACK is received in Cell 1, which is a band. When receiving an instruction to trigger transmission of HARQ-ACK feedback from the base station apparatus 3, the terminal apparatus 1 transmits HARQ-ACK in Cell 1, which is an uplink frequency band readjusted by the RF unit 12. I do.

  Transmission of HARQ-ACK feedback will be described. The base station apparatus 3 transmits information that triggers transmission of HARQ-ACK feedback to the terminal apparatus 1. For example, the base station apparatus 3 transmits information that triggers transmission of HARQ-ACK feedback in DCI format. A dedicated RNTI indicating a DCI format that triggers transmission of HARQ-ACK feedback may be used. A flag indicating the DCI format that triggers transmission of HARQ-ACK feedback may be included in the DCI format. For example, the base station apparatus 3 indicates a resource used for transmitting HARQ-ACK feedback by DCI format. For example, the resource is at least one of a frequency resource, a time resource, and a code resource.

  The terminal device 1 that has received information that triggers transmission of HARQ-ACK feedback from the base station device 3 transmits a plurality of HARQ-ACKs using resources specified by the base station device 3. Information that triggers transmission of HARQ-ACK feedback may be included in the DCI format, and may indicate information indicating resources specified for transmitting a plurality of HARQ-ACKs. A plurality of candidate resources may be specified in advance by the base station device 3, and the terminal device 1 may autonomously select a resource from the plurality of candidate resources and transmit a plurality of HARQ-ACKs.

The terminal device 1 transmits HARQ-ACKs for PDSCHs of a plurality of HARQ processes. The terminal device 1 transmits HARQ-ACKs for PDSCHs of a plurality of HARQ processes in a certain time window. For example, the terminal device 1 transmits a 16-bit HARQ-ACK. Here, each bit corresponds to a different HARQ process, and transmits HARQ-ACK for PDSCH of a total of 16 HARQ processes. Each bit indicates Acknowledgment or Negative acknowledgment. HARQ-ACK for the PDSCH of HARQ process 0, HARQ-ACK for the PDSCH of HARQ process 1, HARQ-ACK for the PDSCH of HARQ process 2, HARQ-ACK for the PDSCH of HARQ process 3, and HARQ process ACK for HARQ process ACK4. HARQ-ACK for PDSCH of HARQ process 5, PDSCH of HARQ process 6
HARQ-ACK for HARQ process 7, PDSCH for HARQ process 8, HARQ-ACK for HARQ process 8 PDSCH, HARQ-ACK for HARQ process 9 PDSCH, HARQ-ACK for HARQ process 10 PDSCH, and HARQ-ACKSCH for HARQ process 10 PDSCH. HARQ-ACK for HARQ process 12 PDSCH, HARQ-ACK for HARQ process 13 PDSCH, HARQ-ACK for HARQ process 14 PDSCH, HARQ-ACK for HARQ process 15 PDSCH, and HARQ-ACK for HARQ process 15 PDSCH. Sent.

  FIG. 19 is a diagram illustrating an example of a procedure according to the embodiment of the present invention. The procedure from the state where the frequency band of LBT subband 0 is set to the transmission of HARQ-ACK in the terminal device 1 will be described. The base station apparatus 3 recognizes that another system is accessing (Busy) in the LBT in the LBT subband 0, and transmits a PDCCH including the DCI format used for the scheduling of the PDSCH in the LBT subband 1, The PDSCH is transmitted using LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband 4. Further, the base station apparatus 3 includes, in the DCI format transmitted in the LBT subband 1, information including an instruction to switch the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH to the UL BWP of the LBT subband 1. Send. The terminal device 1 switches the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH to the UL BWP of the LBT subband 1 while performing the demodulation and the decoding operation of the PDSCH received from the base station device 1. The processing (re-adjustment of the RF unit 12) is started.

  After a lapse of time necessary for the terminal device 1 to switch the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH to the LBT subband 1, the base station device 3 triggers the transmission of the feedback of the HARQ-ACK to the PDSCH. The PDCCH including the information to be transmitted is transmitted to the terminal device 1 using the LBT subband 1. The terminal device 1 receives the PDCCH including information that triggers transmission of HARQ-ACK feedback for the PDSCH, and transmits HARQ-ACK in the LBT subband 1 frequency band.

FIG. 20 is a diagram showing an example of a procedure in the embodiment of the present invention. The procedure from the state where the frequency band of LBT subband 0 is set to the transmission of HARQ-ACK in the terminal device 1 will be described. The base station apparatus 3 recognizes that another system is accessing (Busy) in the LBT in the LBT subband 0, and in each of the PDSCHs in the LBT subband 1, the LBT subband 2, the LBT subband 3, and the LBT subband 4, DCI used for
A PDCCH including a format is transmitted, and a PDSCH is transmitted using each of LBT subband 1, LBT subband 2, LBT subband 3, and LBT subband 4. The base station apparatus 3 transmits the DCI format transmitted in the LBT subband 1 including information instructing to switch the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH to the Cell of the LBT subband 1. I do. The terminal device 1 switches the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH to the cell of the LBT subband 1 while performing the demodulation and the decoding operation of the PDSCH received from the base station device 1. (Readjustment of the RF unit 12) is started.

After a lapse of time necessary for the terminal device 1 to switch the uplink frequency band used for the feedback of the HARQ-ACK to the PDSCH to the LBT subband 1, the base station device 3 triggers the transmission of the feedback of the HARQ-ACK to the PDSCH. The PDCCH including the information to be transmitted is transmitted to the terminal device 1 using the LBT subband 1. The terminal device 1 receives the PDCCH including information that triggers transmission of HARQ-ACK feedback for the PDSCH, and transmits HARQ-ACK in the LBT subband 1 frequency band.

  As described above, while the terminal device 1 is performing the downlink operation, the RF unit 12 can be readjusted to the uplink frequency band used for HARQ-ACK transmission. It is possible to reduce a delay time from when HARQ-ACK can be transmitted after reception. According to the present invention, it is possible to reduce a delay until the base station apparatus 3 can trigger transmission of HARQ-ACK. According to the present invention, the terminal device 1 can efficiently perform broadband communication. Further, the base station device 3 can efficiently perform broadband communication. The present invention is suitable for a terminal device 1 that does not have the processing capability of performing simultaneous transmission of a plurality of UL BWPs or simultaneous transmission of a plurality of UL Carriers.

  Further, a mode in which preparation for transmission of HARQ-ACK is instructed without re-adjustment of the RF unit 12 may be employed. The terminal device 1 performs advance preparations for HARQ-ACK transmission using the UL BWP configuration instructed by the base station device 3. When receiving an instruction to trigger transmission of HARQ-ACK feedback from the base station device 3, the terminal device 1 performs advance preparations so that HARQ-ACK transmission can be performed immediately.

  Hereinafter, aspects of various devices according to one aspect of the present embodiment will be described.

(1) In order to achieve the above object, the embodiment of the present invention has taken the following measures. That is, the first aspect of the present invention provides the DCI used for PDSCH scheduling.
A terminal device for receiving a format, comprising: a receiving unit for receiving the DCI format including an identifier indicating an uplink frequency band used for feedback of HARQ-ACK for the PDSCH; and an RF unit for the uplink frequency band. And a transmitting unit that transmits the HARQ-ACK in the re-adjusted uplink frequency band when receiving an instruction to trigger transmission of the HARQ-ACK feedback from the base station device. It is characterized by having.

  (2) Further, in the first aspect of the present invention, the transmitting unit may readjust the RF unit to the uplink frequency band while the receiving unit is receiving the PDSCH. It is characterized by starting.

  (3) A second aspect of the present invention is a base station apparatus for transmitting a DCI format used for PDSCH scheduling, wherein an uplink frequency band used for HARQ-ACK feedback on the PDSCH is provided. And a transmitting unit that transmits the DCI format including an identifier indicating the HARQ-ACK feedback to the terminal device 1, wherein the HARQ-ACK is transmitted in an uplink frequency band indicated by the identifier. And a receiving unit for receiving ACK.

(4) A third aspect of the present invention is a communication method used in a terminal device that receives a DCI format used for PDSCH scheduling, and is used for uplink HARQ-ACK feedback for the PDSCH. Receiving the DCI format including an identifier indicating a link frequency band, re-adjusting an RF unit to the uplink frequency band, and instructing the base station apparatus to transmit the HARQ-ACK feedback. And receiving the HARQ-ACK in the readjusted uplink frequency band.

  (5) Further, a third aspect of the present invention is characterized in that while the PDSCH is being received, re-adjustment of an RF unit to the uplink frequency band is started.

  (6) A fourth aspect of the present invention is a communication method used in a base station apparatus that transmits a DCI format used for PDSCH scheduling, and is used for feedback of HARQ-ACK for the PDSCH. Transmitting the DCI format including an identifier indicating an uplink frequency band; and, when triggering transmission of the HARQ-ACK feedback to the terminal device 1, the uplink frequency band indicated by the identifier. And receiving the HARQ-ACK.

The program operating on the base station device 3 and the terminal device 1 according to the present invention is a program (for causing a computer to function) that controls a CPU (Central Processing Unit) and the like so as to realize the functions of the above-described embodiment according to the present invention. Program). Information handled by these devices is temporarily stored in a random access memory (RAM) at the time of processing, and thereafter, various types of ROMs such as a flash ROM (read only memory) or an HD
The data is stored in a D (Hard Disk Drive), and is read, corrected, and written by the CPU as needed.

  The terminal device 1 and a part of the base station device 3 in the above-described embodiment may be realized by a computer. In that case, a program for realizing the control function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read and executed by a computer system.

  Here, the “computer system” is a computer system built in the terminal device 1 or the base station device 3 and includes hardware such as an OS and peripheral devices. The “computer-readable recording medium” refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and a storage device such as a hard disk built in a computer system.

  Further, the "computer-readable recording medium" is a medium that dynamically holds the program for a short time, such as a communication line for transmitting the program through a network such as the Internet or a communication line such as a telephone line, In this case, a program holding a program for a certain period of time, such as a volatile memory in a computer system serving as a server or a client, may be included. Further, the above-mentioned program may be for realizing a part of the above-mentioned functions, or may be for realizing the above-mentioned functions in combination with a program already recorded in a computer system.

  Further, the base station device 3 in the above-described embodiment can be realized as an aggregate (device group) including a plurality of devices. Each of the devices constituting the device group may include a part or all of each function or each function block of the base station device 3 according to the above-described embodiment. It is only necessary that the device group has each function or each function block of the base station device 3. Further, the terminal device 1 according to the above-described embodiment can also communicate with the base station device as an aggregate.

Further, the base station device 3 in the above-described embodiment may be an EUTRAN (Evolved Universal Terrestrial Radio Access Network). Further, the base station device 3 in the above-described embodiment may have some or all of the functions of the upper node for the eNodeB.

  In addition, part or all of the terminal device 1 and the base station device 3 in the above-described embodiment may be typically realized as an LSI which is an integrated circuit, or may be realized as a chipset. Each functional block of the terminal device 1 and the base station device 3 may be individually formed into a chip, or a part or all may be integrated and formed into a chip. The method of circuit integration is not limited to an LSI, and may be realized by a dedicated circuit or a general-purpose processor. Further, in the case where a technology for forming an integrated circuit that replaces the LSI appears due to the advance of the semiconductor technology, an integrated circuit based on the technology can be used.

  Further, in the above-described embodiment, the terminal device is described as an example of the communication device. However, the present invention is not limited thereto, and a stationary or non-movable electronic device installed indoors and outdoors, For example, the present invention can be applied to a terminal device or a communication device such as an AV device, a kitchen device, a cleaning / washing device, an air conditioner, an office device, a vending machine, and other living devices.

  As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to the embodiments, and includes a design change or the like without departing from the gist of the present invention. Further, the present invention can be variously modified within the scope shown in the claims, and the technical scope of the present invention includes embodiments obtained by appropriately combining technical means disclosed in different embodiments. It is. The elements described in each of the above embodiments also include a configuration in which elements having the same effects are replaced with each other.

1 (1A, 1B, 1C) Terminal device 3 Base station device 10, 30 Radio transmitting / receiving unit 11, 31 Antenna unit 12, 32 RF unit 13, 33 Baseband unit 14, 34 Upper layer processing unit 15, 35 Medium access control layer Processing Units 16, 36 Radio Resource Control Layer Processing Unit

Claims (6)

A terminal device for receiving a DCI format used for PDSCH scheduling,
A receiving unit that receives the DCI format including an identifier indicating an uplink frequency band used for feedback of HARQ-ACK for the PDSCH;
Re-adjusting the RF unit to the uplink frequency band, when receiving an instruction to trigger transmission of the HARQ-ACK feedback from the base station device, the HARQ-ACK in the readjusted uplink frequency band. A transmitting unit that transmits ACK;
A terminal device comprising:   The terminal device according to claim 1, wherein the transmitting unit starts to readjust an RF unit to the uplink frequency band while the receiving unit is receiving the PDSCH. A base station apparatus for transmitting a DCI format used for PDSCH scheduling,
A transmitting unit that transmits the DCI format including an identifier indicating an uplink frequency band used for feedback of HARQ-ACK for the PDSCH;
A receiving unit that receives the HARQ-ACK in an uplink frequency band indicated by the identifier when transmission of the HARQ-ACK feedback is triggered for the terminal device 1;
A base station device comprising: A communication method used for a terminal device that receives a DCI format used for PDSCH scheduling,
Receiving the DCI format including an identifier indicating an uplink frequency band used for feedback of HARQ-ACK for the PDSCH;
Re-adjusting the RF unit to the uplink frequency band;
When receiving an instruction to trigger transmission of the HARQ-ACK feedback from the base station apparatus, transmitting the HARQ-ACK in the readjusted uplink frequency band;
A communication method comprising:   The communication method according to claim 4, wherein while the PDSCH is being received, readjustment of an RF unit to the uplink frequency band is started. A communication method used for a base station apparatus for transmitting a DCI format used for PDSCH scheduling,
Transmitting the DCI format including an identifier indicating an uplink frequency band used for feedback of HARQ-ACK for the PDSCH;
Receiving the HARQ-ACK in an uplink frequency band indicated by the identifier when triggering transmission of the HARQ-ACK feedback to the terminal device 1;
A communication method comprising:

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