WO2023038058A1 - Terminal device, base station device, and communication method - Google Patents

Abstract

In the present invention, a transport block is received on the PDSCH in a downlink cell managed by a first base station device and a downlink cell managed by a second base station device, and when an error is detected in the transport block on the PDSCH in the downlink cell managed by the second base station device, a random access preamble is transmitted to the second base station device, and a resource indicated in a random access response to the random access preamble is used to transmit an HARQ-ACK for the transport block on the PDSCH in the downlink cell managed by the second base station device.

Description

Terminal device, base station device and communication method

The present invention relates to a terminal device, base station device and communication method.
This application claims priority to Japanese Patent Application No. 2021-145191 filed in Japan on September 7, 2021, the contents of which are incorporated herein.

Radio access schemes and radio networks for cellular mobile communications (hereafter referred to as "Long Term Evolution (LTE)" or "EUTRA: Evolved Universal Terrestrial Radio Access") have been established under the 3rd Generation Partnership Project (3GPP). Project). In LTE, a base station device is also called eNodeB (evolved NodeB), and a terminal device is also called UE (User Equipment). LTE is a cellular communication system in which a plurality of areas covered by base station devices are arranged in a cell. A single base station device may manage multiple serving cells.

　3GPP is studying and standardizing the next-generation standard (NR: New Radio) as a 5G communication method. NR is required to meet the requirements of three scenarios: eMBB (enhanced Mobile BroadBand), mMTC (massive Machine Type Communication), and URLLC (Ultra Reliable and Low Latency Communication) within a single technology framework. there is

It is being studied that a plurality of base station devices communicate simultaneously with terminal devices using different frequency bands (Non-Patent Document 1). Simultaneous communication by three or more base station apparatuses to a certain terminal apparatus is under consideration. Some base station devices use both downlink and uplink frequency bands simultaneously to communicate with terminal devices, and some base station devices use only the downlink frequency band to communicate with terminal devices. . A terminal device performs uplink switching between a plurality of base station devices of a plurality of secondary cell groups.

In order to appropriately control data resending, the data receiving side sends the data sending side the result of data error detection, the result of data reception (whether the received data was It is necessary to appropriately provide feedback such as incorrect data or data not received). The data transmitting side retransmits the data that was not properly received by the receiving side based on the information fed back from the data receiving side. For example, the data transmission side is the base station device, the data reception side is the terminal device, the data is a transport block (the transport block transmitted and received by PDSCH), and the error detection result and reception result of the data are It is HARQ-ACK. Efficient communication is achieved by realizing appropriate retransmission control. One aspect of the present invention provides a terminal device, a base station device, a communication method used in the terminal device, and a communication method used in the base station device, which perform communication efficiently.

(1) A first aspect of the present invention is a terminal device comprising a processor and a memory storing a computer program code, and is transported by PDSCH of a downlink cell managed by a first base station device. Receiving a block, receiving a transport block on PDSCH of a downlink cell managed by a second base station device, and a PDSCH transport block of a downlink cell managed by the second base station device If an error is detected in, a random access preamble is transmitted to the second base station apparatus, and the resource indicated by the random access response to the random access preamble is used by the second base station apparatus to manage transmitting a HARQ-ACK for the PDSCH transport block of the downlink cell.

(2) Furthermore, the HARQ-ACK is indicated by the HARQ process number used for the PDSCH containing the transport block in which the error was detected.

(3) Furthermore, when an error is detected in the PDSCH transport block of the downlink cell managed by the second base station device, the configured uplink managed by the first base station device open the cell.

(4) A second aspect of the present invention is a communication method used in a terminal device, comprising a step of receiving a transport block on the PDSCH of a downlink cell managed by a first base station device; a step of receiving a transport block on the PDSCH of the downlink cell managed by the second base station apparatus; and when an error is detected in the PDSCH transport block of the downlink cell managed by the second base station apparatus , transmitting a random access preamble to the second base station apparatus, and using a resource indicated by a random access response to the random access preamble, transmitting a PDSCH of a downlink cell managed by the second base station apparatus. and sending a HARQ-ACK for the transport block.

(5) A third aspect of the present invention is a base station apparatus comprising a processor and a memory storing computer program code, detecting a random access preamble transmitted from a terminal apparatus, transmitting information indicating uplink resources in a random access response to the cell, and using the resources to receive a HARQ-ACK for the PDSCH transport block of the downlink cell.

According to one aspect of the present invention, the terminal device can communicate efficiently. Also, the base station apparatus can communicate efficiently.

1 is a conceptual diagram of a wireless communication system according to one aspect of the present embodiment; FIG. FIG. 4 is a schematic diagram illustrating an example of a resource grid in a subframe according to one aspect of the present embodiment; 1 is a schematic block diagram showing the configuration of a terminal device 1 according to one aspect of the present embodiment; FIG. 1 is a schematic block diagram showing the configuration of a base station device 3 according to one aspect of the present embodiment; FIG.

Embodiments of the present invention will be described below.

"A and/or B" may be a term including "A", "B", or "A and B".

A parameter or information indicating one or more values may mean that the parameter or information includes at least a parameter or information indicating the one or more values. The higher layer parameter may be a single higher layer parameter. A higher layer parameter may be an information element (IE: Information Element) containing multiple parameters.

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

The base station device 3 may be configured including one or both of MCG (Master Cell Group) and SCG (Secondary Cell Group). MCG is a group of serving cells including at least PCell (Primary Cell). An SCG is a group of serving cells including at least PSCells (Primary Secondary Cells). A PCell is a cell in which an initial connection establishment procedure or a connection re-establishment procedure is implemented by the terminal device 1 (implemented cell). A PSCell is a serving cell in which a random access procedure is performed by the terminal device 1 . An MCG may include one or more SCells (Secondary Cells). An SCG may be configured including one or more SCells. A serving cell identity is a short identifier for identifying a serving cell. The serving cell identifier may be given by a higher layer parameter.

A serving cell group (cell group) is a generic term for MCG, SCG, and PUCCH cell groups. A serving cell group may include one or more serving cells (or component carriers). One or more serving cells (or component carriers) included in a serving cell group may be operated by carrier aggregation.

The terminal device 1 communicates simultaneously with the base station device 3A (third base station device), the base station device 3B (first base station device), and the base station device 3C (second base station device). The base station device 3A, the base station device 3B, and the base station device 3C communicate with the terminal device 1 using different frequency bands (carrier frequency, frequency spectrum). This operation may be referred to as carrier aggregation or dual connectivity. Communication between the terminal device 1 and the base station device 3A, communication between the terminal device 1 and the base station device 3B, and communication between the terminal device 1 and the base station device 3C are each configured by different cells (serving cells). The base station device 3A uses a downlink frequency band and an uplink frequency band. The base station device 3B uses a downlink frequency band and an uplink frequency band. The base station device 3C uses only the downlink frequency band. Alternatively, the base station apparatus 3A uses a downlink frequency band and an uplink frequency band. The base station device 3B uses only the downlink frequency band. The base station apparatus 3C uses a downlink frequency band and an uplink frequency band. In the terminal device 1, the base station device 3 using the uplink frequency band is switched between the base station device 3B and the base station device 3C. In the terminal device 1, the base station device 3 using the uplink frequency band of the secondary cell group is switched between the base station device 3B and the base station device 3C. The base station device 3A, the base station device 3B, and the base station device 3C are connected by wire or wirelessly, and control information, data, and the like are exchanged. The terminal device 1 makes an initial connection with the base station device 3A. After the connection with the base station device 3A is established, the terminal device 1 is added to the connection with the base station device 3B and the base station device 3C. The frequency band used for communication is added to the terminal device 1 . A cell (serving cell) used for communication is added to the terminal device 1 . The terminal device 1 is additionally connected to the base station device 3 .

In the wireless communication system, the terminal device 1 and the base station device 3 may use one or more communication schemes. For example, in the downlink of a radio communication system, CP-OFDM (Cyclic Prefix-Orthogonal Frequency Division Multiplex) may be used. Also, in the uplink of the radio communication system, either CP-OFDM or DFT-s-OFDM (Discrete Fourier Transform-spread-Orthogonal Frequency Division Multiplex) may be used. Here, DFT-s-OFDM is a communication scheme in which transform precoding is applied prior to signal generation in CP-OFDM. Here, modified precoding is also called DFT precoding.

As shown in FIG. 1, the base station device 3 may be configured by one transmitting/receiving device (or transmitting point, transmitting device, receiving point, receiving device, transmitting/receiving point). On the other hand, in some cases, the base station device 3 may be configured including a plurality of transmitting/receiving devices. When the base station device 3 is composed of a plurality of transmitting/receiving devices, each of the plurality of transmitting/receiving devices may be arranged at geographically different positions.

A subcarrier spacing (SCS: SubCarrier Spacing) Δf for a given subcarrier spacing setting μ may be Δf=2 ^μ ×15 kHz. For example, the subcarrier interval setting μ may indicate any one of 0, 1, 2, 3, and 4.

The time unit T _c =1/(Δf _max ×N _f ) may be used for the time domain length representation. Here, Δf _max =480 kHz may be used. Alternatively, N _f =4096. Alternatively, the constant κ may be κ=Δf _max ×N _f /(Δf _ref N _f,ref )=64. Also, Δf _ref may be 15 kHz. N _f,ref is 2048.

The transmission of downlink/uplink signals may be organized into radio frames (system frames, frames) of length Tf. Here, Tf=(Δfmax×Nf/100)×Ts=10 ms may be satisfied.

A radio frame may be configured including 10 subframes. Here, the subframe length Tsf=(Δfmax×Nf/1000)×Ts=1 ms may be used. Also, the number of OFDM symbols per subframe may be Nsubframe, μsymb=Nslotsymb×Nsubframe, μslot.

An OFDM symbol is used as the unit of the time domain of the communication method used in the wireless communication system. For example, an OFDM symbol may be used as a unit of time domain for CP-OFDM. Also, an OFDM symbol may be used as a time domain unit for DFT-s-OFDM.

A slot may consist of multiple OFDM symbols. For example, one slot may consist of consecutive Nslotsymb OFDM symbols. For example, in normal CP settings, Nslotsymb=14. Also, Nslotsymb=12 may be set in the extended CP setting.

The slots may be indexed in the time domain. For example, the slot index nμs may be given in ascending order by integer values ranging from 0 to Nsubframe,μslot−1 in subframes. Also, the slot indices nμs,f may be given in ascending order by integer values ranging from 0 to Nframe,μslot-1 in the radio frame.

FIG. 2 is a diagram showing a configuration example of a resource grid according to one aspect of the present embodiment. In the resource grid of FIG. 2, the horizontal axis is the OFDM symbol index lsym and the vertical axis is the subcarrier index ksc. The resource grid in FIG. 2 includes Nsize, μgrid, x×NRBsc subcarriers and Nsubframe, μsymb OFDM symbols. where Nsize, μgrid, x denotes the bandwidth of the SCS-specific carrier. Also, the units of the values of Nsize, μgrid, and x are resource blocks.

Within the resource grid, a resource identified by subcarrier index ksc and OFDM symbol index lsym is also called a resource element (RE: ResourceElement).

A resource block (RB: Resource Block) includes NRBsc consecutive subcarriers. A resource block is a general term for a common resource block, a physical resource block (PRB), and a virtual resource block (VRB). For example, NRBsc=12.

A BWP (BandWidth Part) may be configured as a subset of the resource grid. Here, the BWP set for the downlink is also called a downlink BWP. A BWP configured for the uplink is also called an uplink BWP.

An antenna port may be defined by the fact that the channel over which the symbols at one antenna port are conveyed can be estimated from the channels over which the other symbols at that antenna port are conveyed. symbol on the antenna port is conveyed can be inferred from the channelover which another symbol on the same antenna port is conveyed). For example, a channel may correspond to a physical channel. A symbol may also correspond to a modulation symbol that is placed on a resource element. Here, "channel" may mean "propagation path". Also, "channel" may mean "physical channel".

Two antenna ports are Quasi Co-Located (QCL) if the large scale property of the channel over which the symbols are conveyed at one antenna port can be estimated from the channel over which the symbols are conveyed at the other antenna port. ) are considered to be in a relationship. Here, the large-scale characteristics may include long-term characteristics of the channel. Large-scale properties are delay spread, Doppler spread, Doppler shift, average gain, average delay, and spatial Rx parameters. You may include a part or all. A first antenna port and a second antenna port are QCL with respect to beam parameters if the receive beam expected by the receiver for the first antenna port and the receive beam expected by the receiver for the second antenna port and may be the same (or correspond). A first antenna port and a second antenna port are QCL with respect to beam parameters if the transmit beam assumed by the receiver for the first antenna port and the transmit beam assumed by the receiver for the second antenna port and may be the same (or correspond). The terminal device 1 assumes that the two antenna ports are QCL when the large-scale characteristics of the channel through which the symbols are transmitted through one antenna port can be estimated from the channel through which the symbols are transmitted through another antenna port. may be Two antenna ports being QCL may be assumed to be two antenna ports being QCL.

Carrier aggregation may be communication using aggregated multiple serving cells. Also, carrier aggregation may be communication using a plurality of aggregated component carriers. Also, carrier aggregation may be communication using a plurality of aggregated downlink component carriers. Also, carrier aggregation may be communication using a plurality of aggregated uplink component carriers.

A configuration example of the terminal device 1 according to one aspect of the present embodiment will be described below.

FIG. 3 is a schematic block diagram showing the configuration of the terminal device 1 according to one aspect of the present embodiment. As illustrated, the terminal device 1 includes a radio transmitting/receiving section 10 and an upper layer processing section 14 . The radio transmitting/receiving section 10 includes at least part or all of an antenna section 11 , an RF (Radio Frequency) section 12 , and a baseband section 13 . The upper layer processing unit 14 includes at least part or all of the medium access control layer processing unit 15 and the radio resource control layer processing unit 16 . The radio transmitting/receiving unit 10 is also called a transmitting unit, a receiving unit, or a physical layer processing unit.

The wireless transmission/reception unit 10 performs physical layer processing.

For example, the radio transmitting/receiving unit 10 may generate a baseband signal for an uplink physical channel. Here, transport blocks delivered from higher layers on the UL-SCH may be arranged in uplink physical channels. For example, the radio transmitting/receiving unit 10 may generate baseband signals of uplink physical signals.

For example, the radio transmitting/receiving unit 10 may attempt to detect information transmitted by a downlink physical channel. Here, transport blocks among the information conveyed by the downlink physical channel may be delivered to higher layers on the DL-SCH. For example, the physical layer processing unit 10 may attempt to detect information conveyed by downlink physical signals.

The receiving unit of the terminal device 1 receives the PDSCH. The reception processing unit of the terminal device 1 performs processing for receiving PDSCH in the downlink frequency band (cell, component carrier, carrier). The reception processing unit of the terminal device 1 performs processing such as demodulation and decoding on the PDSCH.

The transmission unit (also called transmission processing unit) of the terminal device 1 transmits HARQ-ACK. The transmission processing unit of the terminal device 1 transmits HARQ-ACK for PDSCH. The transmission processing unit of the terminal device 1 transmits HARQ-ACK in the uplink frequency band (cell, component carrier, carrier).

The upper layer processing unit 14 outputs uplink data (transport blocks) generated by the user's operation or the like to the radio transmission/reception unit 10 . The upper layer processing unit 14 processes the MAC layer, packet data convergence protocol (PDCP) layer, radio link control (RLC) layer, and RRC layer.

A medium access control layer processing unit (MAC layer processing unit) 15 provided in the upper layer processing unit 14 performs MAC layer processing.

The radio resource control layer processing unit 16 provided in the upper layer processing unit 14 performs RRC layer processing. The radio resource control layer processing unit 16 manages various setting information/parameters (RRC parameters) of its own device. The radio resource control layer processing unit 16 sets various setting information/parameters (RRC 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 (RRC parameters) based on information indicating various setting information/parameters (RRC parameters) received from the base station device 3 . The configuration information may include information related to processing or configuration of physical channels, physical signals (that is, physical layer), MAC layer, PDCP layer, RLC layer, and RRC layer. The parameters may be higher layer parameters.

For example, the radio resource control layer processing unit 16 may acquire RRC parameters included in an RRC message on a certain logical channel and set the acquired RRC parameters in the storage area of the terminal device 1 . The RRC parameters set in the storage area of the terminal device 1 may be provided to lower layers.

The radio resource control layer processing unit 16 may include function information generated based on the functions provided in the terminal device 1 in the RRC message and transmit it to the base station device 3 .

The radio transmission/reception unit 10 performs modulation processing, encoding processing, and transmission processing. The radio transmitting/receiving unit 10 generates a physical signal through encoding processing, modulation processing, and baseband signal generation processing (conversion into a time-continuous signal) for data (transport block), and transmits the physical signal to the base station device 3 .

The radio transmission/reception unit 10 performs demodulation processing, decoding processing, and reception processing. The radio transmitting/receiving unit 10 outputs the transport block among the information detected based on the demodulation processing and decoding processing for the received physical signal to the upper layer processing unit 14 on the DL-SCH.

The RF section 12 converts the signal received via the antenna section 11 into a baseband signal (down-convert) and removes unnecessary frequency components. The RF section 12 outputs the baseband signal to the baseband section 13 .

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

The baseband unit 13 performs inverse fast Fourier transform (IFFT) on the physical signal to generate OFDM symbols. The baseband unit 13 adds a CP to the generated OFDM symbol to generate a baseband digital signal. The baseband unit 13 converts the baseband digital signal into an analog signal. The baseband section 13 outputs the converted analog signal to the RF section 12 .

The RF unit 12 uses a low-pass filter to remove unnecessary frequency components from the analog signal input from the baseband unit 13, upconverts the analog signal to a carrier frequency, and generates an RF signal. The RF section 12 transmits RF signals via the antenna section 11 . Also, the RF unit 12 amplifies power. Also, the RF unit 12 may have a function of controlling transmission power. The RF section 12 is also called a transmission power control section.

A configuration example of the base station device 3 according to one aspect of the present embodiment will be described below.

FIG. 4 is a schematic block diagram showing the configuration of the base station device 3 according to one aspect of this embodiment. As illustrated, the base station device 3 includes a radio transmitting/receiving section 30 and a higher layer processing section 34 . The radio transmitting/receiving section 30 includes an antenna section 31 , an RF (Radio Frequency) section 32 and a baseband section 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 radio transmitting/receiving unit 30 is also called a transmitting unit, a receiving unit, or a physical layer processing unit.

The upper layer processing unit 34 includes a MAC (Medium Access Control) layer, a packet data convergence protocol (PDCP: Packet Data Convergence Protocol) layer, a radio link control (RLC: Radio Link Control) layer, a radio resource control (RRC: Radio Resource Control ) layer processing. Here, the MAC layer is also called MAC sublayer. The PDCP layer is also called a PDCP sublayer. An RLC layer is also referred to as an RLC sublayer. The RRC layer is also called an RRC sublayer.

The medium access control layer processing unit 35 provided in the upper layer processing unit 34 performs MAC layer processing. Here, MAC layer processing includes mapping between logical channels and transport channels, multiplexing of one or more MAC SDUs (Service Data Units) into transport blocks, and delivery from the physical layer on UL-SCH. It may include some or all of decomposing a transport block into one or more MAC SDUs, applying HARQ (Hybrid Automatic Repeat reQuest) to the transport block, and processing scheduling requests.

A radio resource control layer processing unit 36 provided in the upper layer processing unit 34 performs RRC layer processing. The processing of the RRC layer may include part or all of management of broadcast signals, management of RRC connection/RRC idle state, and RRC reconfiguration. The radio resource control layer processing unit 36 generates downlink data (transport blocks), system information, RRC messages, MAC CE, etc. arranged in the PDSCH, or acquires them from upper nodes, and outputs them to the radio transmitting/receiving unit 30. .

Also, the radio resource control layer processing unit 36 manages various setting information/parameters (RRC parameters) of each terminal device 1 . The radio resource control layer processing unit 36 may set various setting information/parameters for each terminal device 1 via an upper layer signal. That is, the radio resource control layer processing unit 36 transmits/notifies information indicating various setting information/parameters. The configuration information may include information related to processing or configuration of physical channels, physical signals (that is, physical layer), MAC layer, PDCP layer, RLC layer, and RRC layer. The parameters may be higher layer parameters. For example, the radio resource control layer processing unit 36 may include an RRC parameter in an RRC message on a certain logical channel and transmit the RRC parameter to the terminal device 1 . Here, the RRC message may be mapped to any of BCCH (Broadcast Control CHannel), CCCH (Common Control CHannel), and DCCH (Dedicated Control CHannel).

The radio resource control layer processing unit 36 may determine the RRC parameters to be transmitted to the terminal device 1 based on the RRC parameters included in the RRC message transmitted from the terminal device 1 . Here, the RRC message transmitted from the terminal device 1 may relate to the capability information report of the terminal device 1 .

The radio resource control layer processing unit 36 sets resources for HARQ-ACK transmission for the terminal device 1 . The radio resource control layer processing unit 36 sets resources for HARQ-ACK transmission for the PDSCH of the downlink frequency band (cell, component carrier, carrier). The radio resource control layer processing unit 36 sets the resource for HARQ-ACK transmission for PDSCH to the uplink frequency band (cell, component carrier, carrier).

The functions of the radio transmitting/receiving section 30 are the same as those of the radio transmitting/receiving section 10, so description thereof will be omitted as appropriate. The radio transmitting/receiving unit 30 performs physical layer processing. Here, the processing of the physical layer includes generation of baseband signals for physical channels, generation of baseband signals for physical signals, detection of information transmitted from physical channels, and detection of information transmitted by physical signals. It may include part or all. The physical layer processing may also include the mapping of transport channels to physical channels. Here, the baseband signal is also called a time-continuous signal.

The radio transmitting/receiving section 30 may perform one or both of demodulation processing and decoding processing. The radio transmitting/receiving unit 30 may deliver the transport block of the information detected based on the demodulation processing and decoding processing for the received physical signal to the upper layer on the UL-SCH. For example, the radio transmitting/receiving unit 30 may generate a baseband signal of a downlink physical channel. Here, transport blocks delivered from higher layers on the DL-SCH may be arranged in downlink physical channels. For example, the radio transmitting/receiving unit 30 may generate a baseband signal of a downlink physical signal.

The radio transmitting/receiving section 30 may perform part or all of the modulation processing, encoding processing, and transmission processing. The radio transmitting/receiving section 30 may generate the physical signal based on part or all of the encoding processing, modulation processing, and baseband signal generation processing for the transport block. The radio transmitting/receiving unit 30 may arrange physical signals in a certain BWP. The radio transceiver 30 may transmit the generated physical signal. For example, the radio transceiver 30 may attempt to detect information conveyed by uplink physical channels. Here, transport blocks among the information carried by the uplink physical channel may be delivered to higher layers on the UL-SCH. For example, the radio transceiver 30 may attempt to detect information conveyed by uplink physical signals.

The receiving unit (also called reception processing unit) of the base station device 3 receives HARQ-ACK. The reception processing unit of the base station apparatus 3 receives HARQ-ACK for PDSCH. The reception processing unit of the base station device 3 receives HARQ-ACK in the uplink frequency band (cell, component carrier, carrier). The reception processing unit of the base station device 3 receives HARQ-ACK for the PDSCH of the downlink frequency band (cell, component carrier, carrier) managed by the base station device 3 .

The RF section 32 may convert the signal received via the antenna section 31 into a baseband signal and remove unnecessary frequency components. The RF section 32 outputs the baseband signal to the baseband section 33 .

The baseband section 33 may digitize the baseband signal input from the RF section 32 . The baseband unit 33 may remove a portion corresponding to CP (Cyclic Prefix) from the digitized baseband signal. The baseband unit 33 may perform a fast Fourier transform (FFT) on the CP-removed baseband signal to extract a signal in the frequency domain.

The baseband unit 33 may generate a baseband signal by inverse fast Fourier transform (IFFT) of the physical signal. The baseband unit 33 may add CP to the generated baseband signal. The baseband unit 33 may analogize the baseband signal to which the CP is added. The baseband section 33 may output the analogized baseband signal to the RF section 32 .

The RF section 32 may remove extra frequency components from the baseband signal input from the baseband section 33 . The RF section 32 may upconvert the baseband signal to a carrier frequency to generate the RF signal. The RF section 32 may transmit RF signals via the antenna section 31 . Also, the RF unit 32 may have a function of controlling transmission power.

Each of the units denoted by reference numerals 10 to 16 provided in the terminal device 1 may be configured as a circuit. Each of the units denoted by reference numerals 30 to 36 provided in the base station device 3 may be configured as a circuit.

Physical channels and physical signals (physical signals) according to various aspects of the present embodiment will be described below.

A physical signal is a general term for a downlink physical channel, a downlink physical signal, an uplink physical channel, and an uplink physical channel. A physical channel is a general term for a downlink physical channel and an uplink physical channel. A physical signal is a general term for a downlink physical signal and an uplink physical signal.

An uplink physical channel may correspond to a set of resource elements that carry information originating in higher layers. An uplink physical channel is a physical channel used in an uplink component carrier. The uplink physical channel may be transmitted by the radio transceiver 10 . The uplink physical channel may be received by the radio transceiver 30 . In a radio communication system according to an aspect of the present embodiment, at least some or all of the following uplink physical channels are used.
・PUCCH (Physical Uplink Control Channel)
・PUSCH (Physical Uplink Shared CHannel)
・PRACH (Physical Random Access CHannel)

PUCCH may be used to transmit (convey) uplink control information (UCI). Uplink control information may be arranged in PUCCH. The radio transmitting/receiving unit 10 may transmit PUCCH in which uplink control information is arranged. The physical layer processing unit 30 may receive PUCCH in which uplink control information is arranged.

Uplink control information (uplink control information bit, uplink control information sequence, uplink control information type) includes channel state information (CSI: Channel State Information), scheduling request (SR: Scheduling Request), HARQ-ACK (Hybrid (Automatic Repeat request ACKnowledgement) information in part or in full. Note that the uplink control information may include information not described above.

　Channel state information is also called a channel state information bit or a channel state information sequence. A scheduling request is also called a scheduling request bit or a scheduling request sequence. HARQ-ACK information is also called HARQ-ACK information bits or HARQ-ACK information sequence.

The HARQ-ACK information may consist of HARQ-ACK bits corresponding to one transport block (TB). The HARQ-ACK bit may indicate ACK (acknowledgement) or NACK (negative-acknowledgement) corresponding to the transport block. ACK may indicate that decoding of the transport block has been successfully completed (has been decoded). A NACK may indicate that decoding of the transport block has not been successfully completed (has not been decoded). HARQ-ACK information may include one or more HARQ-ACK bits.

　HARQ-ACK for transport blocks is also called HARQ-ACK for PDSCH. Here, "HARQ-ACK for PDSCH" may indicate HARQ-ACK for transport blocks included in PDSCH.

A scheduling request may be used to request UL-SCH resources for initial transmission. The scheduling request bit may be used to indicate either positive SR or negative SR. The fact that the scheduling request bit indicates positive SR is also referred to as "positive SR is transmitted (carried)". A positive SR may indicate that UL-SCH resources are requested by the terminal device 1 for initial transmission. The fact that the scheduling request bit indicates negative SR is also referred to as "negative SR is transmitted (conveyed)". A negative SR may indicate that no UL-SCH resources are requested by the terminal device 1 for initial transmission.

The channel state information may include some or all of a channel quality indicator (CQI: Channel Quality Indicator), a precoder matrix indicator (PMI: Precoder Matrix Indicator), and a rank indicator (RI: Rank Indicator). CQI is an index related to channel quality (eg, propagation strength) or physical channel quality, and PMI is an index related to precoders. RI is an index related to transmission rank (or number of transmission layers).

　Channel state information is an index related to the reception state of physical signals (eg, CSI-RS) used for channel measurement. The value of the channel state information may be determined by the terminal device 1 based on reception conditions assumed by the physical signals used for channel measurements. Channel measurements may include interference measurements.

PUCCH may be accompanied by a certain PUCCH format. Here, the PUCCH format may be a PUCCH physical layer processing format. Also, the PUCCH format may be a format of information transmitted using the PUCCH.

PUSCH may be transmitted to convey one or both of uplink control information and transport blocks. PUSCH may be used to convey one or both of uplink control information and transport blocks. PUSCH may be used to transmit at least some or all of transport blocks, HARQ-ACK, channel state information and scheduling requests. PUSCH is used at least to transmit random access message 3. PUSCH may be used to transmit information not listed above. The terminal device 1 may transmit PUSCH in which one or both of uplink control information and transport blocks are arranged. The base station apparatus 3 may receive PUSCH in which one or both of uplink control information and transport blocks are arranged.

A PRACH may be sent to convey the random access preamble index (random access message 1). The terminal device 1 may transmit PRACH. The base station device 3 may receive the PRACH. The terminal device 1 may transmit a random access preamble on PRACH. The base station device 3 may receive a random access preamble on PRACH.

An uplink physical signal may correspond to a set of resource elements. Uplink physical signals may not be used to convey information originating in higher layers. Note that the uplink physical signal may be used to convey information generated in the physical layer. The uplink physical signal may be a physical signal used in an uplink component carrier. The radio transmitting/receiving unit 10 may transmit an uplink physical signal. The radio transmitting/receiving unit 30 may receive an uplink physical signal. Some or all of the following uplink physical signals may be used in the uplink of the radio communication system according to one aspect of the present embodiment.
・UL DMRS (Uplink Demodulation Reference Signal)
・SRS (Sounding Reference Signal)
・UL PTRS (Uplink Phase Tracking Reference Signal)

　UL DMRS is a generic term for DMRS for PUSCH and DMRS for PUCCH.

A set of antenna ports for DMRS for PUSCH (DMRS related to PUSCH, DMRS included in PUSCH, DMRS corresponding to PUSCH) may be given based on the set of antenna ports for the PUSCH. For example, the set of DMRS antenna ports for a PUSCH may be the same as the set of antenna ports for the PUSCH.

The PUSCH propagation path may be estimated from the DMRS for the PUSCH.

The set of antenna ports of DMRS for PUCCH (DMRS related to PUCCH, DMRS included in PUCCH, DMRS corresponding to PUCCH) may be the same as the set of antenna ports of PUCCH.

A PUCCH channel may be estimated from the DMRS for the PUCCH.

A downlink physical channel may correspond to a set of resource elements that convey information originating in higher layers. A downlink physical channel may be a physical channel used in a downlink component carrier. The radio transmitting/receiving unit 30 may transmit downlink physical channels. The radio transceiver 10 may receive a downlink physical channel. Some or all of the following downlink physical channels may be used in the downlink of the radio communication system according to one aspect of the present embodiment.
・PBCH (Physical Broadcast Channel)
・PDCCH (Physical Downlink Control Channel)
・PDSCH (Physical Downlink Shared Channel)

The PBCH is transmitted to convey one or both of the Master Information Block (MIB) and physical layer control information. Here, the physical layer control information is information generated in the physical layer. MIB is an RRC message delivered from the upper layer on BCCH (Broadcast Control CHannel).

The PDCCH is used at least for transmission (conveyance) of downlink control information (DCI). Downlink control information may be placed in the PDCCH. The terminal device 1 may receive a PDCCH in which downlink control information is arranged. The base station device 3 may transmit a PDCCH in which downlink control information is arranged.

The downlink control information may be transmitted with the DCI format. Note that the DCI format may be interpreted as the format of downlink control information. A DCI format may also be interpreted as a set of downlink control information set to a certain downlink control information format.

The base station device 3 may notify the terminal device 1 of downlink control information using a PDCCH with a DCI format. Here, the terminal device 1 may monitor the PDCCH to acquire downlink control information. Note that the DCI format and downlink control information are sometimes described as being equivalent, unless there is a special explanation. For example, the base station apparatus 3 may include downlink control information in the DCI format and transmit it to the terminal apparatus 1 . Also, the terminal device 1 may control the physical layer processing unit 10 using downlink control information included in the detected DCI format.

The downlink control information may include at least either a downlink grant (DL grant) or an uplink grant (UL grant). A DCI format used for PDSCH scheduling is also referred to as a downlink DCI format. The DCI format used for PUSCH scheduling is also called an uplink DCI format. Downlink grants are also called downlink assignments (DL assignments) or downlink allocations (DL allocations).

　DCI format 0_0, DCI format 0_1, DCI format 1_0, and DCI format 1_1 are DCI formats. The uplink DCI format is a general term for DCI format 0_0 and DCI format 0_1. A downlink DCI format is a general term for DCI format 1_0 and DCI format 1_1.

DCI format 0_0 is used for scheduling of PUSCHs arranged in a certain cell. DCI format 0_0 includes at least part or all of 1A to 1E.
1A) Identifier for DCI formats field
1B) Frequency domain resource assignment field
1C) Time domain resource assignment field
1D) Frequency hopping flag field
1E) MCS field (MCS field: Modulation and Coding Scheme field)

The DCI format specific field may indicate whether the DCI format including the DCI format specific field is an uplink DCI format or a downlink DCI format. That is, the DCI format specific field may be included in each of the uplink DCI format and the downlink DCI format. Here, the DCI format specific field included in DCI format 0_0 may indicate 0.

The frequency domain resource allocation field included in DCI format 0_0 may be used to indicate frequency resource allocation for PUSCH scheduled by this DCI format 0_0.

The time domain resource allocation field included in DCI format 0_0 may be used to indicate the allocation of time resources for PUSCH scheduled by that DCI format 0_0.

A frequency hopping flag field may be used to indicate whether frequency hopping is applied to the PUSCH scheduled by the DCI format 0_0.

The MCS field included in DCI format 0_0 is used to indicate one or both of the modulation scheme for PUSCH scheduled by the DCI format 0_0 and the target coding rate scheduled by the DCI format 0_1. good too. The target code rate may be the target code rate for transport blocks placed on the PUSCH. The transport block size (TBS: Transport Block Size) allocated to PUSCH may be determined based on the target coding rate and part or all of the modulation scheme for PUSCH.

DCI format 0_0 may not include fields used for CSI requests (CSI requests). DCI format 0_0 may not include a carrier indicator field. DCI format 0_0 may not contain the BWP field.

DCI format 0_1 is used for scheduling of PUSCHs arranged in a certain cell. DCI format 0_1 is configured to include some or all of fields 2A to 2H.
2A) DCI format specific fields
2B) Frequency domain resource allocation field
2C) Time domain resource allocation field
2D) Frequency hopping flag field
2E) MCS field
2F) CSI request field
2G) BWP field
2H) UL DAI field (downlink assignment index)

The DCI format specific field included in DCI format 0_1 may indicate 0.

The frequency domain resource allocation field included in DCI format 0_1 may be used to indicate frequency resource allocation for PUSCH scheduled by this DCI format 0_1.

The time domain resource allocation field included in DCI format 0_1 may be used to indicate the time resource allocation for PUSCH scheduled by this DCI format 0_1.

The MCS field included in DCI format 0_1 indicates one or both of the modulation scheme for PUSCH scheduled by DCI format 0_1 and the target coding rate for PUSCH scheduled by DCI format 0_1. may be used for

The CSI request field may be used to indicate CSI reporting.

The BWP field of DCI format 0_1 may be used to indicate the uplink BWP in which the PUSCH scheduled by DCI format 0_1 is allocated. That is, DCI format 0_1 may or may not be accompanied by a change of the active uplink BWP. The terminal device 1 may recognize the uplink BWP in which the PUSCH is allocated based on detecting the DCI format 0_1 used for PUSCH scheduling.

A DCI format 0_1 that does not include a BWP field may be a DCI format that schedules PUSCH without changing the active uplink BWP. The terminal device 1 transmits the PUSCH without switching the active uplink BWP based on detecting the DCI format 0_1 that is used for PUSCH scheduling and does not include the BWP field. can recognize that.

Although the BWP field is included in DCI format 0_1, the BWP field may be ignored by terminal device 1 if terminal device 1 does not support the function of switching BWP by DCI format 0_1. That is, the terminal device 1 that does not support the BWP switching function switches the active uplink BWP based on detecting the DCI format 0_1 used for PUSCH scheduling and the DCI format 0_1 including the BWP field. It may be recognized to transmit the PUSCH without performing Here, if the BWP switching function is supported, the radio resource control layer processing unit 16 may include function information indicating that the BWP switching function is supported in the RRC message.

When DCI format 0_1 includes a carrier indicator field, the carrier indicator field may be used to indicate the serving cell of the uplink component carrier on which PUSCH is allocated. Based on detecting DCI format 0_1 in the downlink component carrier of a certain serving cell, the terminal device 1 detects the uplink of the serving cell in which the PUSCH scheduled by the DCI format 0_1 is indicated by the carrier indicator field included in the DCI format 0_1. It may be recognized that it is located on a component carrier.

When the carrier indicator field is not included in DCI format 0_1, the serving cell to which the uplink component carrier on which the PUSCH scheduled by DCI format 0_1 is assigned belongs to the downlink component carrier on which the PDCCH including the DCI format 0_1 is assigned. It may be the same as the serving cell. Based on detecting DCI format 0_1 in a certain downlink component carrier of a certain serving cell, the terminal device 1 recognizes that the PUSCH scheduled according to the DCI format 0_1 is allocated to the uplink component carrier of the certain serving cell. good too.

　The UL DAI field is used at least to indicate the PDSCH transmission status. If the Dynamic HARQ-ACK codebook is used, the size of the UL DAI field may be 2 bits. The UL DAI field indicates the size of the HARQ-ACK codebook transmitted on PUSCH. The UL DAI field indicates the number of HARQ-ACKs included in the HARQ-ACK codebook transmitted on PUSCH. The UL DAI field indicates the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on PUSCH. The UL DAI field indicates the number of PDSCH and SPS releases in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on PUSCH.

　The UL DAI field may indicate a value to which a modulo operation has been applied. An example in which the UL DAI field is 2 bits will be described. If the HARQ-ACK codebook transmitted on the PUSCH has 0 PDSCHs containing the corresponding HARQ-ACKs, the UL DAI field indicates "00". If the HARQ-ACK codebook transmitted on the PUSCH includes one PDSCH containing the corresponding HARQ-ACK, "01" is indicated as the UL DAI field. If the HARQ-ACK codebook transmitted on the PUSCH includes two PDSCHs containing corresponding HARQ-ACKs, "10" is indicated as the UL DAI field. If the HARQ-ACK codebook transmitted on the PUSCH includes three PDSCHs containing corresponding HARQ-ACKs, "11" is indicated as the UL DAI field. If the HARQ-ACK codebook transmitted on the PUSCH includes four PDSCHs containing corresponding HARQ-ACKs, "00" is indicated as the UL DAI field. If the HARQ-ACK codebook transmitted on the PUSCH includes five PDSCHs containing corresponding HARQ-ACKs, the UL DAI field is indicated as "01". When the HARQ-ACK codebook transmitted by PUSCH includes 6 PDSCHs containing corresponding HARQ-ACKs, "10" is indicated as the UL DAI field. If the HARQ-ACK codebook transmitted on the PUSCH contains 7 PDSCHs containing corresponding HARQ-ACKs, "11" is indicated as the UL DAI field. In this example, in the HARQ-ACK codebook transmitted on PUSCH, modulo arithmetic using the numerical value '4' is performed on the number of PDSCHs in which the corresponding HARQ-ACK is included.

The terminal device 1 interprets the UL DAI field considering the total number of received PDSCHs. For example, the terminal device 1 receives four PDSCHs and receives the UL DAI field indicating "00". In this case, the terminal device 1 interprets that the number of PDSCHs containing corresponding HARQ-ACKs in the HARQ-ACK codebook transmitted by PUSCH indicated by the UL DAI field is four. For example, the terminal device 1 receives three PDSCHs and receives the UL DAI field indicating "00". In this case, the terminal device 1 interprets that the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted by PUSCH, which is indicated by the UL DAI field, is four, and one PDSCH is It is determined that reception has failed.

DCI format 1_0 is used for PDSCH scheduling allocated to a certain cell. DCI format 1_0 includes part or all of 3A to 3F.
3A) DCI format specific fields
3B) Frequency domain resource allocation field
3C) Time domain resource allocation field
3D) MCS field
3E) PDSCH to HARQ feedback timing indicator field
3F) PUCCH resource indicator field

The DCI format specific field included in DCI format 1_0 may indicate 1.

The frequency domain resource allocation field included in DCI format 1_0 may be used to indicate frequency resource allocation for PDSCH scheduled by that DCI format.

The time domain resource allocation field included in DCI format 1_0 may be used to indicate time resource allocation for PDSCHs scheduled by that DCI format.

The MCS field included in DCI format 1_0 is used to indicate one or both of the modulation scheme for PDSCH scheduled by this DCI format and the target coding rate for PDSCH scheduled by this DCI format. may be The target code rate may be the target code rate for transport blocks placed on the PDSCH. The transport block size (TBS: Transport Block Size) allocated to the PDSCH may be determined based on one or both of the target coding rate and the modulation scheme for the PDSCH.

The PDSCH_HARQ feedback timing indication field may be used to indicate the offset from the slot containing the last OFDM symbol of PDSCH to the slot containing the first OFDM symbol of PUCCH. The timing indication field from PDSCH to HARQ feedback may be a field indicating timing K1. When the index of the slot containing the last OFDM symbol of PDSCH is slot n, the index of the slot containing PUCCH or PUSCH containing at least HARQ-ACK corresponding to the transport block contained in the PDSCH is n+K1. There may be. When the index of the slot containing the last OFDM symbol of PDSCH is slot n, the OFDM symbol at the beginning of PUCCH or the OFDM symbol at the beginning of PUSCH including at least HARQ-ACK corresponding to the transport block included in the PDSCH is The included slot index may be n+K1.

The PDSCH_HARQ feedback timing indication field may also be called a PDSCH-to-HARQ feedback timing indicator field (PDSCH-to-HARQ_feedback timing indicator field) or a HARQ indication field.

The PUCCH resource indication field may be used to indicate PUCCH resources.

　DCI format 1_0 may not include a carrier indicator field. That is, the downlink component carrier on which the PDSCH scheduled by DCI format 1_0 is mapped may be the same as the downlink component carrier on which the PDCCH including DCI format 1_0 is mapped. Based on detecting DCI format 1_0 in a certain downlink component carrier, the terminal device 1 may recognize that the PDSCH scheduled according to DCI format 1_0 should be mapped to that downlink component carrier.

　DCI format 1_0 does not have to include the BWP field. Here, the DCI format 1_0 may be a DCI format that schedules the PDSCH without changing the active downlink BWP. Based on detecting the DCI format 1_0 used for PDSCH scheduling, the terminal device 1 may recognize that the PDSCH will be received without switching the active downlink BWP.

DCI format 1_1 is used for scheduling PDSCHs allocated to a certain cell. DCI format 1_1 includes part or all of 4A to 4I.
4A) DCI format specific fields
4B) Frequency Domain Resource Allocation Field
4C) Time Domain Resource Allocation Field
4E) MCS field
4F) PDSCH_HARQ feedback timing indication field
4G) PUCCH resource indication field
4H) BWP field
4I) Carrier Indicator Field

The DCI format specific field included in DCI format 1_1 may indicate 1.

The frequency domain resource allocation field included in DCI format 1_1 may be used to indicate frequency resource allocation for PDSCH scheduled by this DCI format 1_1.

The time domain resource allocation field included in DCI format 1_1 may be used to indicate time resource allocation for the PDSCH scheduled by this DCI format 1_1.

The MCS field included in DCI format 1_1 indicates one or both of the modulation scheme for PDSCH scheduled by DCI format 1_1 and the target coding rate for PDSCH scheduled by DCI format 1_1. may be used for

When DCI format 1_1 includes the PDSCH_HARQ feedback timing indication field, the PDSCH_HARQ feedback timing indication field indicates the offset from the slot including the last OFDM symbol of PDSCH to the slot including the first OFDM symbol of PUCCH. may be used for If the DCI format 1_1 does not include the PDSCH_HARQ feedback timing indication field, a parameter indicating the offset from the slot including the last OFDM symbol of PDSCH to the slot including the first OFDM symbol of PUCCH is provided by the RRC layer. may

The PUCCH resource indication field may be used to indicate PUCCH resources.

The BWP field of DCI format 1_1 may be used to indicate the downlink BWP in which the PDSCH scheduled by DCI format 1_1 is allocated. That is, DCI format 1_1 may or may not involve changing the active downlink BWP. The terminal device 1 may recognize the downlink BWP in which the PDSCH is allocated based on detecting the DCI format 1_1 used for PDSCH scheduling.

A DCI format 1_1 that does not include a BWP field may be a DCI format that schedules PDSCHs without changing the active downlink BWP. The terminal device 1 receives the PDSCH without switching the active downlink BWP based on detecting the DCI format 1_1 that is used for PDSCH scheduling and does not include the BWP field. can recognize that.

Although the DCI format 1_1 includes a BWP field, the BWP field may be ignored by the terminal device 1 if the terminal device 1 does not support the function of switching the BWP according to the DCI format 1_1. That is, the terminal device 1 that does not support the BWP switching function switches the active downlink BWP based on detecting the DCI format 1_1 used for PDSCH scheduling and the DCI format 1_1 including the BWP field. It may be recognized that the PDSCH is received without performing Here, if the BWP switching function is supported, the radio resource control layer processing unit 16 may include function information indicating that the BWP switching function is supported in the RRC message.

When the DCI format 1_1 includes a carrier indicator field, the carrier indicator field may be used to indicate the serving cell of the downlink component carrier in which the PDSCH scheduled by the DCI format 1_1 is arranged. Based on detecting DCI format 1_1 in the downlink component carrier of a certain serving cell, the terminal device 1 detects the downlink of the serving cell in which the PDSCH scheduled by the DCI format 1_1 is indicated by the carrier indicator field included in the DCI format 1_1. It may be recognized that it is located on a component carrier.

When the DCI format 1_1 does not include a carrier indicator field, the downlink component carrier on which the PDSCH scheduled by the DCI format 1_1 is assigned is the same as the downlink component carrier on which the PDCCH including the DCI format 1_1 is assigned. may Based on detecting DCI format 1_1 in a certain downlink component carrier, the terminal device 1 may recognize that the PDSCH scheduled according to DCI format 1_1 should be mapped to that downlink component carrier.

A downlink grant is used at least for scheduling one PDSCH in one serving cell. A downlink grant is used at least for scheduling PDSCHs in the same slot in which the downlink grant was transmitted. A downlink grant may be used for scheduling PDSCHs in slots different from the slot in which the downlink grant was transmitted. An uplink grant is used at least for scheduling one PUSCH in one serving cell.

It should be noted that various DCI formats may further include fields different from the above fields. A field indicating the cumulative number of transmitted PDCCHs (C-DAI: Counter Downlink Assignment Index field) may be included. A field indicating the total number of PDCCHs to be transmitted (T-DAI: Total Downlink Assignment Index field) may be included.

The PDSCH may be transmitted to convey transport blocks. PDSCH may be used to convey transport blocks. A transport block may be placed on the PDSCH. The base station apparatus 3 may transmit PDSCH in which transport blocks are arranged. The terminal device 1 may receive PDSCH in which transport blocks are arranged.

A downlink physical signal may correspond to a set of resource elements. Downlink physical signals may not be used to convey information originating in higher layers. Note that the downlink physical signal may be used to convey information generated in the physical layer. A downlink physical signal may be a physical signal used in a downlink component carrier. The radio transceiver 10 may receive a downlink physical signal. The radio transmitting/receiving unit 30 may transmit a downlink physical signal. In the downlink of the radio communication system according to one aspect of this embodiment, at least some or all of the following downlink physical signals may be used.
・Synchronization signal (SS)
・DL DMRS (DownLink DeModulation Reference Signal)
・CSI-RS (Channel State Information-Reference Signal)
・DL PTRS (DownLink Phase Tracking Reference Signal)

The synchronization signal is used by the terminal device 1 to synchronize the downlink frequency domain and/or time domain. A synchronization signal is a general term for PSS (Primary Synchronization Signal) and SSS (Secondary Synchronization Signal).

　The SS block (SS/PBCH block) includes at least part or all of the PSS, SSS, and PBCH.

The PSS, SSS, PBCH, and DMRS antenna ports for the PBCH may be the same.

A PBCH to which a PBCH symbol in a certain antenna port is transmitted is a DMRS for the PBCH that is mapped to the slot to which the PBCH is mapped, and is for the PBCH included in the SS/PBCH block that includes the PBCH. may be estimated by the DMRS of

DL DMRS is a generic term for DMRS for PBCH, DMRS for PDSCH, and DMRS for PDCCH.

A set of antenna ports for DMRS for PDSCH (DMRS related to PDSCH, DMRS included in PDSCH, DMRS corresponding to PDSCH) may be given based on the set of antenna ports for the PDSCH. For example, the set of DMRS antenna ports for a PDSCH may be the same as the set of antenna ports for the PDSCH.

A PDSCH propagation path may be estimated from the DMRS for the PDSCH. If a set of resource elements in which a certain PDSCH symbol is transmitted and a set of resource elements in which a DMRS symbol for the certain PDSCH is transmitted are included in the same Precoding Resource Group (PRG) In that case, the PDSCH on which the PDSCH symbols on a given antenna port are conveyed may be estimated by the DMRS for that PDSCH.

The antenna port of DMRS for PDCCH (DMRS related to PDCCH, DMRS included in PDCCH, DMRS corresponding to PDCCH) may be the same as the antenna port for PDCCH.

A PDCCH channel may be estimated from the DMRS for the PDCCH. If the same precoder is applied (assumed to be applied, applicable), the PDCCH on which the symbols of that PDCCH at a certain antenna port are conveyed may be estimated by the DMRS for that PDCCH.

BCH (Broadcast CHannel), UL-SCH (Uplink-Shared CHannel), and DL-SCH (Downlink-Shared CHannel) are transport channels.

The transport layer BCH may be mapped to the physical layer PBCH. That is, a transport block delivered from a higher layer on the BCH of the transport layer may be placed on the PBCH of the physical layer. Also, the transport layer UL-SCH may be mapped to the physical layer PUSCH.

The transport layer may apply HARQ (Hybrid Automatic Repeat reQuest) to transport blocks.

BCCH (Broadcast Control CHannel), CCCH (Common Control CHannel), and DCCH (Dedicated Control CHannel) are logical channels. For example, BCCH may be used to deliver RRC messages containing MIBs or RRC messages containing system information. CCCH may also be used to transmit an RRC message including RRC parameters common to multiple terminal devices 1 . Here, CCCH may be used, for example, for terminal device 1 that is not RRC-connected. DCCH may also be used to transmit RRC messages dedicated to a terminal device 1 . Here, the DCCH may be used, for example, for the terminal device 1 that is RRC-connected.

BCCH may be mapped to BCH or DL-SCH. That is, RRC messages containing MIB information may be delivered to the BCH. Also, RRC messages containing system information other than the MIB may be delivered to the DL-SCH. CCCH is also mapped to DL-SCH or UL-SCH. That is, RRC messages mapped to CCCH may be delivered on DL-SCH or UL-SCH. Also, DCCH may be mapped to DL-SCH or UL-SCH. That is, RRC messages mapped to DCCH may be delivered to DL-SCH or UL-SCH.

　UL-SCH may be mapped to PUSCH. DL-SCH may be mapped to PDSCH. A BCH may be mapped to a PBCH.

The medium access control layer processing unit 15 may implement a random access procedure.

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

One physical channel may be mapped to one serving cell. One physical channel may be mapped to one BWP configured on one carrier included in one serving cell.

　The terminal device 1 may be configured with one or more control resource sets (CORESET: Control Resource SET). The terminal device 1 monitors PDCCH in one or more control resource sets (monitor). Here, monitoring PDCCHs in one or more control resource sets may include monitoring one or more PDCCHs respectively corresponding to one or more control resource sets. Note that a PDCCH may include one or more PDCCH candidates and/or a set of PDCCH candidates. Also, monitoring the PDCCH may include monitoring and detecting the PDCCH and/or a DCI format transmitted over the PDCCH.

A plurality of control resource sets may be configured in the terminal device 1, and an index (control resource set index) may be assigned to each control resource set. One or more control channel elements (CCEs) may be configured in the control resource set and each CCE may be assigned an index (CCE index).

A set of PDCCH candidates (PDCCH candidates) monitored by the terminal device 1 is defined from the viewpoint of a search space. That is, the set of PDCCH candidates monitored by the terminal device 1 is given by the search area.

A search area may be configured to include one or more PDCCH candidates of one or more aggregation levels. The PDCCH candidate aggregation level may indicate the number of CCEs forming the PDCCH. A PDDCH candidate may be mapped to one or more CCEs.

A search area set may be configured to include at least one or more search areas. An index (search area index) may be assigned to each search area.

Each search area set may be associated with at least one control resource set. Each of the search area sets may be included in one control resource set. For each search area set, an index of the control resource set associated with the search area set may be provided.

The terminal device 1 can detect the PDCCH and/or DCI for the terminal device 1 by blind-detecting PDCCH candidates included in the search region within the control resource set.

In various aspects of the present embodiment, the number of resource blocks indicates the number of resource blocks in the frequency domain unless otherwise specified.

The terminal device 1 transmits uplink control information (UCI) to the base station device 3. The terminal device 1 may multiplex the UCI with the PUCCH and transmit. The terminal device 1 may multiplex the UCI with the PUSCH and transmit. UCI includes downlink channel state information (Channel State Information: CSI), scheduling request (Scheduling Request: SR) that indicates the request for PUSCH resources, downlink data (Transport block, Medium Access Control Protocol Data Unit: MAC PDU, Downlink - Shared Channel: DL-SCH, Physical Downlink Shared Channel: PDSCH) may include at least one of HARQ-ACK (Hybrid Automatic Repeat request ACKnowledgement).

HARQ-ACK may also be called ACK/NACK, HARQ feedback, HARQ-ACK feedback, HARQ response, HARQ-ACK response, HARQ information, HARQ-ACK information, HARQ control information, and HARQ-ACK control information. .

When the downlink data is successfully decoded, an ACK is generated for the downlink data. If the downlink data is not successfully decoded, a NACK is generated for the downlink data. The HARQ-ACK may include at least HARQ-ACK bits corresponding to at least one transport block. The HARQ-ACK bit may indicate ACK (ACKnowledgement) or NACK (Negative-ACKnowledgement) corresponding to one or more transport blocks. HARQ-ACK may include at least a HARQ-ACK codebook containing one or more HARQ-ACK bits. The HARQ-ACK bits corresponding to one or more transport blocks may correspond to the PDSCH containing the one or more transport blocks.

　HARQ control for one transport block may be called a HARQ process. One HARQ process identifier may be given per HARQ process. The DCI format contains a field indicating the HARQ process number.

　NDI (New Data Indicator) is indicated in DCI format for each HARQ process. For example, a DCI format (DL assignment) containing PDSCH scheduling information includes an NDI field. The NDI field is 1 bit. The terminal device 1 stores (memorizes) the value of NDI for each HARQ process. The base station device 3 stores (memorizes) the NDI value for each HARQ process for each terminal device 1 . The terminal device 1 updates the stored NDI value using the detected NDI field of the DCI format. The base station apparatus 3 sets the updated NDI value or the non-updated NDI value in the NDI field of the DCI format and transmits it to the terminal apparatus 1 . The terminal device 1 uses the detected NDI field of the DCI format to update the stored NDI value for the HARQ process corresponding to the detected value of the HARQ process identifier field of the DCI format.

The terminal device 1 determines whether the received transport block is a new transmission or a retransmission based on the value of the NDI field of the DCI format (DL assignment). The terminal device 1 compares the value of NDI previously received for a transport block of a certain HARQ process, and if the value of the NDI field of the detected DCI format has been toggled, the received transport block is It is determined that it is a new transmission. When transmitting a newly transmitted transport block in a certain HARQ process, the base station device 3 toggles the NDI value stored for the HARQ process and transmits the toggled NDI to the terminal device 1 . When transmitting a transport block for retransmission in a certain HARQ process, the base station device 3 does not toggle the NDI value stored for that HARQ process, and transmits the non-toggled NDI to the terminal device 1 . The terminal device 1 compares the value of NDI previously received for a transport block of a certain HARQ process, and if the value of the NDI field of the detected DCI format has not been toggled (if it is the same), the received determine that the received transport block is a retransmission. Note that toggling here means switching to a different value.

The terminal device 1 stores HARQ-ACK information in a DCI format 1_0 corresponding to PDSCH reception or in a slot indicated by the value of the HARQ indication field included in DCI format 1_1, in a HARQ-ACK codebook. ) may be used to report to the base station apparatus 3 .

For DCI format 1_0, the value of the HARQ indication field may be mapped to a set of slot numbers (1, 2, 3, 4, 5, 6, 7, 8). For DCI format 1_1, the value of the HARQ indication field may be mapped to the set of slot numbers given by the higher layer parameter dl-DataToUL-ACK. The number of slots indicated at least based on the value of the HARQ indication field may also be referred to as HARQ-ACK timing, or K1. For example, HARQ-ACK representing the decoding state of PDSCH (downlink data) transmitted in slot n may be reported (transmitted) in slot n+K1.

　dl-DataToUL-ACK indicates a list of HARQ-ACK timings for PDSCH. Timing is the number of slots between the slot in which the PDSCH is received (or the slot containing the last OFDM symbol to which the PDSCH is mapped) and the slot in which the HARQ-ACK for the received PDSCH is transmitted. be. For example, dl-DataToUL-ACK is a list of 1, or 2, or 3, or 4, or 5, or 6, or 7, or 8 timings. If Dl-DataToUL-ACK is a list of one timing, the HARQ indication field is 0 bits. If Dl-DataToUL-ACK is a list of 2 timings, the HARQ indication field is 1 bit. If Dl-DataToUL-ACK is a list of 3 or 4 timings, the HARQ indication field is 2 bits. If the Dl-DataToUL-ACK is a list of 5, 6, 7, or 8 timings, the HARQ indication field is 3 bits. For example, dl-DataToUL-ACK consists of a list of timing values anywhere in the range 0-31. For example, dl-DataToUL-ACK consists of a list of timing values anywhere from 0 to 63.

The size of dl-DataToUL-ACK is defined as the number of elements that dl-DataToUL-ACK contains. The size of Dl-DataToUL-ACK may be referred to as L _para . The index of Dl-DataToUL-ACK indicates the order (number) of the elements of dl-DataToUL-ACK. For example, if the size of dl-DataToUL-ACK is 8 (L _para =8), the index of dl-DataToUL-ACK is either 1, 2, 3, 4, 5, 6, 7, or 8. value. The index of Dl-DataToUL-ACK may be given, indicated, or indicated by the value indicated by the HARQ indication field.

The terminal device 1 may set the size of the HARQ-ACK codebook according to the size of dl-DataToUL-ACK. For example, if dl-DataToUL-ACK consists of 8 elements, the size of HARQ-ACK codebook is 8. For example, if dl-DataToUL-ACK consists of two elements, the size of HARQ-ACK codebook is two. Each HARQ-ACK information constituting the HARQ-ACK codebook is HARQ-ACK information for PDSCH reception at each slot timing of dl-DataToUL-ACK. This type of HARQ-ACK codebook is also called Semi-static HARQ-ACK codebook.

The terminal device 1 may report HARQ-ACK information for PDSCH reception in slot n using PUCCH transmission and/or PUSCH transmission in slot n+k. Here, k may be the number of slots indicated by the HARQ indication field included in the DCI format corresponding to the PDSCH reception. Also, if the HARQ indication field is not included in the DCI format, k may be given by the higher layer parameter dl-DataToUL-ACK.

The terminal device 1 determines a set of multiple opportunities for one or more candidate PDSCH receptions to transmit corresponding HARQ-ACK information on PUCCH of a slot. The terminal device 1 determines that multiple slots with slot timing K1 included in dl-DataToUL-ACK are multiple opportunities for candidate PDSCH reception. K1 may be a set of k. For example, when dl-DataToUL-ACK is (1, 2, 3, 4, 5, 6, 7, 8), in PUCCH of slot n, PDSCH reception of slot n-1, PDSCH of slot n-2 Receive, PDSCH receive on slot n-3, PDSCH receive on slot n-4, PDSCH receive on slot n-5, PDSCH receive on slot n-6, PDSCH receive on slot n-7, n-8 HARQ-ACK information for the PDSCH reception of the slot is transmitted. When the terminal device 1 actually receives the PDSCH in the slot corresponding to the candidate PDSCH reception, the terminal device 1 sets ACK or NACK as the HARQ-ACK broadcast based on the transport block included in the PDSCH, and sets the HARQ-ACK broadcast to receive the candidate PDSCH. If PDSCH is not received in the corresponding slot, NACK is set as HARQ-ACK information.

A HARQ-ACK codebook may be given based at least on the set of Monitoring occasions for PDCCH, some or all of the values of the counter DAI field. A HARQ-ACK codebook may be given based on the value of the UL DAI field. A HARQ-ACK codebook may be given based on the value of the DAI field. A HARQ-ACK codebook may be given based on the value of the total DAI field.

The size of the HARQ-ACK codebook may be set based on the value of the last received DCI format counter DAI field. The Counter DAI field indicates the cumulative number of PDSCHs or transport blocks scheduled until reception of the corresponding DCI format. The size of the HARQ-ACK codebook may be set based on the value of the Total DAI field in DCI format. The Total DAI field indicates the total number of PDSCHs or transport blocks scheduled until transmission of the HARQ-ACK codebook.

The terminal device 1 sets a set of PDCCH monitoring opportunities for HARQ-ACK information transmitted on the PUCCH allocated to the slot of index n (slot#n) with the value of timing K1 and the value of slot offset K0. may be determined based at least on part or all of The set of PDCCH monitoring occasions for HARQ-ACK information transmitted on PUCCH located in slot of index n is also called the set of PDCCH monitoring occasions for PDCCH for slot#n. called. Here, the set of PDCCH monitoring opportunities includes M PDCCH monitoring opportunities. For example, the slot offset K0 may be indicated based at least on the value of the time domain resource allocation field included in the downlink DCI format. The slot offset K0 is from the slot containing the last OFDM symbol in which the PDCCH containing the DCI format including the time domain resource allocation field indicating the slot offset K0 is arranged to the first OFDM symbol of the PDSCH scheduled according to the DCI format. is a value indicating the number of slots (slot difference) in

If the DCI format detected in any search area set monitoring opportunity corresponding to a certain PDCCH monitoring opportunity triggers (including the triggering information) to transmit HARQ-ACK information in slot n, the terminal device 1 may determine the PDCCH monitoring opportunity to be the PDCCH monitoring opportunity for slot n. Also, if the DCI format detected in the monitoring opportunity of the search area set corresponding to a certain PDCCH monitoring opportunity does not trigger (does not include triggering information) to transmit HARQ-ACK information in slot n, the terminal device 1 may not determine the PDCCH monitoring opportunity as the PDCCH monitoring opportunity for slot n. Also, if the DCI format is not detected in the search area set monitoring opportunity corresponding to a certain PDCCH monitoring opportunity, the terminal device 1 may not determine the PDCCH monitoring opportunity as the PDCCH monitoring opportunity for slot n. .

Counter DAI is the cumulative number of PDCCHs (or cumulative may be at least a value associated with a number). Counter DAI may also be referred to as C-DAI. A C-DAI corresponding to a PDSCH may be indicated by a field included in the DCI format used for scheduling the PDSCH. Total DAI may indicate the cumulative number of PDCCHs (or at least a value related to the cumulative number) detected by PDCCH monitoring opportunity m in M PDCCH monitoring opportunities. The total DAI may be called T-DAI (Total Downlink Assignment Index).

A switching process of the uplink frequency band (uplink cell) for transmission of HARA-ACK information in one embodiment of the present invention will be described.

The terminal device 1 communicates simultaneously with the base station device 3A (third base station device), the base station device 3B (first base station device), and the base station device 3C (second base station device). At a certain timing, the terminal device 1 uses the downlink frequency band and the uplink frequency band for communication (connection) with the base station device 3A, and the terminal device 1 uses the downlink frequency band for communication (connection) with the base station device 3B. A link frequency band and an uplink frequency band are used, and the terminal device 1 uses only the downlink frequency band for communication (connection) with the base station device 3C. In other words, the terminal device 1 uses a downlink cell (downlink cell 1) and an uplink cell (uplink cell 1) for communication (connection) with the base station device 3A. A downlink cell (downlink cell 2) and an uplink cell (uplink cell 2) are used for communication (connection) with the device 3B, and the terminal device 1 communicates (connects) with the base station device 3C. Only the downlink cell (downlink cell 3) is used.

At a certain timing, the base station device 3A communicates (connects) with the terminal device 1 using the downlink frequency band and the uplink frequency band, and the base station device 3B communicates (connects) with the terminal device 1. , the base station apparatus 3C uses only the downlink frequency band for communication (connection) with the terminal apparatus 1. FIG. In other words, the base station device 3A uses a downlink cell (downlink cell 1) and an uplink cell (uplink cell 1) for communication (connection) with the terminal device 1, and the base station device 3B uses the terminal device 1 for communication (connection). A downlink cell (downlink cell 2) and an uplink cell (uplink cell 2) are used for communication (connection) with the device 1, and the base station device 3C communicates (connects) with the terminal device 1. Only the downlink cell (downlink cell 3) is used.

The terminal device 1 transmits HARQ-ACK information for the transport block included in the PDSCH received in the downlink frequency band used with the base station device 3A to the uplink frequency used with the base station device 3A. Send in band. The terminal device 1 transmits HARQ-ACK information for the transport block included in the PDSCH received in the downlink cell 1 used with the base station device 3A to the uplink cell used with the base station device 3A. Send with 1. The terminal device 1 transmits HARQ-ACK information for the transport block included in the PDSCH received in the downlink frequency band used with the base station device 3B to the uplink frequency used with the base station device 3B. Send in band. The terminal device 1 transmits HARQ-ACK information for the transport block included in the PDSCH received in the downlink cell 2 used with the base station device 3B to the uplink cell used with the base station device 3B. 2 to send. The HARQ-ACK information transmission used here uses the above-described HARQ-ACK information transmission method. A method using a dynamic HARQ-ACK codebook or a semi-static HARA-ACK codebook, for example using various fields in the DCI format, is used.

The base station device 3A transmits HARQ-ACK information for the transport block included in the PDSCH transmitted in the downlink frequency band used with the terminal device 1 to the uplink frequency used with the terminal device 1. receive in the band. The base station device 3A transmits HARQ-ACK information for the transport block included in the PDSCH transmitted in the downlink cell 1 used with the terminal device 1 to the uplink cell used with the terminal device 1. 1 to receive. The base station apparatus 3B sends HARQ-ACK information for the transport block included in the PDSCH transmitted in the downlink frequency band used with the terminal apparatus 1 to the uplink frequency used with the terminal apparatus 1. receive in the band. The base station apparatus 3B transmits HARQ-ACK information for the transport block included in the PDSCH transmitted in the downlink cell 2 used with the terminal apparatus 1 to the uplink cell used with the terminal apparatus 1. 2 to receive.

The terminal device 1 is allocated resources used for transmitting a signal for notifying the base station device 3 that the uplink frequency band (uplink cell) will be switched. A random access preamble is used as the signal, and resources of the random access preamble (random access preamble index, PRACH time position (period and offset), PRACH frequency position) are allocated to the terminal device 1 . Here, in the terminal device 1, a resource (resource in the uplink cell 2) used for transmitting a signal for notifying the base station device 3B of switching the uplink frequency band (uplink cell) are assigned by the base station apparatus 3B. The signal for notifying the base station apparatus 3 of switching the uplink frequency band (uplink cell) may be a dedicated PUCCH signal.

The base station device 3 allocates the resource of the random access preamble used for notifying that the terminal device 1 will switch the uplink frequency band (uplink cell) to the terminal device 1 . The base station apparatus 1 notifies the terminal apparatus 1 of the allocation information using RRC parameters (RRC signaling). Here, the base station apparatus 3B allocates in advance a random access preamble resource for the terminal apparatus 1 to notify that the uplink frequency band (uplink cell) is to be switched to the terminal apparatus 1, and transmits the allocation information to the terminal apparatus 1. It is notified to the terminal device 1 by a parameter (RRC signaling).

The base station device 3B may transmit information indicating that the random access preamble has been detected to the terminal device 1. The terminal device 1 may start the process of switching the uplink cell to the base station device 3C based on the information indicating that the random access preamble has been detected from the base station device 3B. When the PUCCH is used as a signal for notifying the base station apparatus 3B of switching the uplink frequency band (uplink cell), the terminal apparatus 1 detects the PUCCH from the base station apparatus 3B. Based on the reception of the indicating information, the base station apparatus 3C may start the process of switching the uplink cell. Information indicating detection of the random access preamble or information indicating detection of PUCCH may be transmitted using PDSCH or PDCCH.

When the terminal device 1 detects an error in the transport block included in the PDSCH received in the downlink frequency band (downlink cell 3) used between the terminal device 1 and the base station device 3C, the assigned random access preamble to the base station device 3B. The terminal device 1 releases the uplink frequency band (uplink cell 2) used with the base station device 3B, and releases the uplink frequency band (uplink cell 2) with the base station device 3C. Change the settings to use cell 3). That is, the terminal device 1 performs uplink cell switching in the SCG. The terminal device 1 switches SCGs for setting uplink cells. The terminal device 1 switches the base station device 3 that configures the uplink cell in the SCG.

Upon detecting the random access preamble, the base station device 3B releases the uplink frequency band (uplink cell 2) set for the terminal device 1.

The terminal device 1 is assigned resources for a random access preamble to be transmitted to the base station device 3C in uplink cell switching. When the terminal device 1 detects an error in the transport block included in the PDSCH received in the downlink frequency band (downlink cell 3) used between the terminal device 1 and the base station device 3C, the base station device 3C transmit a random access preamble.

The base station apparatus 3C allocates the random access preamble resource used by the terminal apparatus 1 to switch uplink cells and notify the HARQ-ACK information to the terminal apparatus 1, and uses the allocation information as an RRC parameter (RRC signaling). is notified to the terminal device 1 by .

The base station device 3C that has detected the random access preamble transmits a random access response to the terminal device 1. The random access response includes information indicating uplink resources. The terminal device 1 receives the random access response and uses the resource indicated in the random access response to transmit PDSCH transport blocks of the downlink cell (downlink cell 3) managed by the base station device 3C. HARQ-ACK information is transmitted to the base station device 3C. The resource indicated in the random access response may be a PUSCH resource. The resource indicated in the random access response may be a PUCCH resource.

The HARQ-ACK information may be indicated by the HARQ process number used for the PDSCH containing the transport block in which the error was detected. The terminal device 1 transmits information indicating the HARQ process number used for the PDSCH containing the transport block in which the error was detected to the base station device 3C using the resource indicated by the random access response.

Based on the HARQ-ACK information received from the terminal device 1, the base station device 3C retransmits the PDSCH including the transport block in which the error was detected to the terminal device 1. Based on the HARQ process number indicated by the HARQ-ACK information transmitted by the terminal apparatus 1, the base station apparatus 3C determines that an error has been detected in the PDSCH transport block corresponding to the HARQ process number.

Thereafter, the terminal device 1 receives the HARQ-ACK information for the transport block included in the PDSCH received in the downlink frequency band (downlink cell 3) used with the base station device 3C as described above. Transmit using a method using a HARQ-ACK codebook or a quasi-static HARA-ACK codebook. When the terminal device 1 detects an error in the transport block included in the PDSCH received in the downlink frequency band (downlink cell 3) used between the terminal device 1 and the base station device 3B, the assigned random access is performed. A preamble is transmitted to the base station apparatus 3C. Similarly, the resources (resources in the uplink cell 3) used for transmitting a signal for notifying the base station device 3C of switching the uplink frequency band (uplink cell) are supplied from the base station device 3C. It is assigned to the terminal device 1. The terminal device 1 releases the uplink frequency band (uplink cell 3) used with the base station device 3C, and releases the uplink frequency band (uplink cell 3) with the base station device 3B. Change the settings to use cell 2).

The terminal device 1 is assigned resources for a random access preamble to be transmitted to the base station device 3B when switching between cells in the uplink. When the terminal device 1 detects an error in the transport block included in the PDSCH received in the downlink frequency band (downlink cell 2) used between the terminal device 1 and the base station device 3B, the base station device 3B transmit a random access preamble.

The base station device 3B that has detected the random access preamble transmits a random access response to the terminal device 1. The random access response includes information indicating uplink resources. The terminal device 1 receives the random access response and uses the resource indicated in the random access response to transmit the PDSCH transport block of the downlink cell (downlink cell 2) managed by the base station device 3B. HARQ-ACK information is transmitted to the base station apparatus 3B.

Here, it is preferable that conservative scheduling is used in the downlink cell of the base station apparatus 3 in which the uplink cell is not set in the terminal apparatus 1 . Increased redundancy by lowering the modulation level and coding rate than for cells where HARQ-ACK information is exchanged using a dynamic HARQ-ACK codebook or a quasi-static HARQ-ACK codebook Scheduling is preferred so that the In the downlink cell of the base station apparatus 3 in which the uplink cell is set in the terminal apparatus 1, scheduling using adaptive modulation is preferably used without increasing redundancy.

As described above, according to one aspect of the present invention, HARQ-ACK information can be appropriately exchanged between the terminal device 1 and the base station device 3. As a result, the base station device 3 can appropriately control retransmission of data. Efficient communication is achieved by realizing appropriate retransmission control.

Aspects of various devices according to one aspect of the present embodiment will be described below.

(1) In order to achieve the above objects, the aspects of the present invention take the following measures. That is, a first aspect of the present invention is a terminal device comprising a processor and a memory storing a computer program code, wherein the PDSCH of the downlink cell managed by the first base station device transport block receiving a transport block in the PDSCH of the downlink cell managed by the second base station device, in the PDSCH transport block of the downlink cell managed by the second base station device When an error is detected, a random access preamble is transmitted to the second base station apparatus, and a resource indicated by a random access response to the random access preamble is used for downlink managed by the second base station apparatus. transmitting a HARQ-ACK for the PDSCH transport block of the cell of the link.

(2) Furthermore, the HARQ-ACK is indicated by the HARQ process number used for the PDSCH containing the transport block in which the error was detected.

(3) Furthermore, when an error is detected in the PDSCH transport block of the downlink cell managed by the second base station device, the configured uplink managed by the first base station device open the cell.

(4) A second aspect of the present invention is a communication method used in a terminal device, comprising a step of receiving a transport block on the PDSCH of a downlink cell managed by a first base station device; a step of receiving a transport block on the PDSCH of the downlink cell managed by the second base station apparatus; and when an error is detected in the PDSCH transport block of the downlink cell managed by the second base station apparatus , transmitting a random access preamble to the second base station apparatus, and using a resource indicated by a random access response to the random access preamble, transmitting a PDSCH of a downlink cell managed by the second base station apparatus. and sending a HARQ-ACK for the transport block.

(5) A third aspect of the present invention is a base station apparatus comprising a processor and a memory storing computer program code, detecting a random access preamble transmitted from a terminal apparatus, transmitting information indicating uplink resources in a random access response to the cell, and using the resources to receive a HARQ-ACK for the PDSCH transport block of the downlink cell.

A program that operates on the base station device 3 and the terminal device 1 according to one aspect of the present invention controls a CPU (Central Processing Unit) and the like so as to realize the functions of the above-described embodiments related to one aspect of the present invention. It may be a program (a program that causes a computer to function). The information handled by these devices is temporarily stored in RAM (Random Access Memory) during processing, and then stored in various ROMs such as Flash ROM (Read Only Memory) and HDD (Hard Disk Drive). It is read, modified, and written by the CPU as necessary.

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

The "computer system" here is a computer system built into the terminal device 1 or the base station device 3, and includes hardware such as an OS and peripheral devices. The term "computer-readable recording medium" refers to portable media such as flexible discs, magneto-optical discs, ROMs and CD-ROMs, and storage devices such as hard disks built into computer systems.

Furthermore, "computer-readable recording medium" means a medium that dynamically stores a program for a short period of time, such as a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line. It may also include a volatile memory inside a computer system that serves as a server or client in that case, which holds the program for a certain period of time. Further, the program may be for realizing part of the functions described above, or may be capable of realizing the functions described above in combination with a program already recorded in the computer system.

The terminal device 1 may consist of at least one processor and at least one memory containing computer program instructions (computer program). The memory and computer program instructions (computer program) may be configured to cause the terminal device 1 to perform the operations and processes described in the above embodiments using a processor. The base station device 3 may consist of at least one processor and at least one memory containing computer program instructions (computer programs). The memory and computer program instructions (computer program) may be configured to cause the base station apparatus 3 to perform the operations and processes described in the above embodiments using a processor.

Also, the base station device 3 in the above-described embodiment can be realized as an aggregate (device group) composed of a plurality of devices. Each of the devices constituting the device group may include a part or all of each function or each functional block of the base station device 3 related to the above-described embodiments. A device group may have a series of functions or functional blocks of the base station device 3 . Also, the terminal device 1 according to the above-described embodiments can communicate with a base station device as a group.

Also, the base station device 3 in the above-described embodiment may be EUTRAN (Evolved Universal Terrestrial Radio Access Network) and/or NG-RAN (NextGen RAN, NR RAN). Also, the base station device 3 in the above-described embodiment may have some or all of the functions of an upper node for eNodeB and/or gNB.

Also, part or all of the terminal device 1 and the base station device 3 in the above-described embodiments may be typically implemented as an LSI, which is an integrated circuit, or may be implemented as a chipset. Each functional block of the terminal device 1 and the base station device 3 may be individually chipped, or part or all of them may be integrated and chipped. Also, the method of circuit integration is not limited to LSI, but may be realized by a dedicated circuit or a general-purpose processor. In addition, when a technology for integrating circuits that replaces LSIs emerges due to advances in semiconductor technology, it is also possible to use integrated circuits based on this technology.

In addition, in the above-described embodiments, a terminal device was described as an example of a communication device, but the present invention is not limited to this. For example, it can be applied to terminal devices or communication devices such as AV equipment, kitchen equipment, cleaning/washing equipment, air conditioning equipment, office equipment, vending machines, and other household equipment.

Although the embodiment of this invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes etc. within the scope of the gist of this invention are also included. Further, one aspect of the present invention can be modified in various ways within the scope of the claims, and an embodiment obtained by appropriately combining technical means disclosed in different embodiments can also be Included in the scope. Moreover, it is an element described in each said embodiment, and the structure which replaced the element with which the same effect is produced is also included.

One aspect of the present invention is, for example, a communication system, a communication device (e.g., a mobile phone device, a base station device, a wireless LAN device, or a sensor device), an integrated circuit (e.g., a communication chip), or a program, etc. be able to.

1 (1A, 1B, 1C) terminal device 3 (3A, 3B, 3C) 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 units

Claims (5)

1. A terminal device comprising a processor and a memory storing computer program code, the terminal device receiving a transport block on PDSCH of a downlink cell managed by a first base station device, and a second base station device. receiving a transport block on the PDSCH of the downlink cell managed by the second base station apparatus, and when an error is detected in the PDSCH transport block of the downlink cell managed by the second base station apparatus, a random access preamble HARQ for PDSCH transport blocks of downlink cells managed by the second base station apparatus, transmitted to the second base station apparatus and using resources indicated by a random access response to the random access preamble - A terminal device that performs an action including sending an ACK.
2. 　The terminal device according to claim 1, wherein the HARQ-ACK is indicated by the HARQ process number used for the PDSCH containing the transport block in which the error was detected.
3. When an error is detected in a PDSCH transport block of a downlink cell managed by the second base station apparatus, a request to release the set uplink cell managed by the first base station apparatus. Item 1. The terminal device according to item 1.
4. A communication method used in a terminal device, comprising: a step of receiving a transport block on the PDSCH of a downlink cell managed by a first base station device; receiving a PDSCH transport block; and transmitting a random access preamble to the second base station device when an error is detected in the PDSCH transport block of a downlink cell managed by the second base station device. and using the resource indicated in the random access response to the random access preamble to transmit HARQ-ACK for the PDSCH transport block of the downlink cell managed by the second base station apparatus; , communication methods.
5. A base station apparatus comprising a processor and a memory storing computer program code, the base station apparatus detecting a random access preamble transmitted from a terminal apparatus, and information indicating uplink resources in a random access response to the random access preamble. and receiving a HARQ-ACK for a PDSCH transport block of a downlink cell using the resource.

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