Terminal device, base station device, and communication method

Abstract

In the present invention, a first upper limit and a number of configured PDCCH candidates are used to adjust a number of PDCCH candidates monitored in each slot, and a second upper limit and the number of PDCCH candidates adjusted on the basis of the first upper limit are used to adjust a number of PDCCH candidates monitored in multiple slots.

Description

[Technical Field]

[0001] The present invention relates to a terminal device, a base station device, and a communication method. This application claims priority to Japanese Patent Application No. 2021-42015, filed on March 16, 2021, the contents of which are incorporated herein by reference. [Background technology]

[0002] A radio access method and a radio network for cellular mobile communications (hereinafter referred to as "Long Term Evolution (LTE)" or "EUTRA: Evolved Universal Terrestrial Radio Access") are being studied by the 3rd Generation Partnership Project (3GPP). In LTE, a base station device is also called an eNodeB (evolved NodeB), and a terminal device is also called a UE (User Equipment). LTE is a cellular communication system in which areas covered by a base station device are arranged in multiple cells. A single base station device may manage multiple serving cells.

[0003] 3GPP is currently studying and standardizing the next-generation standard (NR: New Radio) as the communication method for 5G. NR is expected 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.

[0004] Support for NR in the frequency band from 52.6 GHz to 71 GHz is also being considered (Non-Patent Document 1). In addition to the 120 kHz subcarrier spacing, the introduction of subcarrier spacings of 480 kHz and 960 kHz is being considered. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] "Revised WID: Extending current NR operation to 71GHz", RP-202925, CMCC 3GPP TSG RAN Meeting #90-e, Electronic Meeting, 7-11 December, 2020. Summary of the Invention [Problem to be solved by the invention]

[0006] As the subcarrier spacing increases, the length of one slot becomes shorter, increasing the processing load within one slot. Therefore, there is a demand for improvements in PDCCH (Physical Downlink Control CHannel) monitoring. While applying multi-slot scheduling, which allocates PDSCH or PUSCH resources for multiple slots in one PDCCH, monitoring such PDCCHs for multiple slots rather than for each slot is being considered. Meanwhile, from the viewpoint of backward compatibility, it is desirable to apply single-slot scheduling, which allocates one PDSCH or PUSCH resource in one PDCCH, for transmission and reception of system information, random access responses, etc. In a situation where multi-slot scheduling and single-slot scheduling are used together, there is a demand for efficient processing related to PDCCH monitoring. One aspect of the present invention provides a terminal device, a base station device, a communication method, and a communication method that perform efficient communication. [Means for solving the problem]

[0007] (1) In order to achieve the above object, one aspect of the present invention provides the following means. That is, a first aspect of the present invention is a terminal device including a processor and a memory that stores computer program code, the terminal device receiving RRC signaling indicating a configuration of a search space including at least a period, an offset, and the number of PDCCH candidates for each aggregation level, configuring PDCCH candidates for each slot based on the RRC signaling indicating the configuration of the search space, and adjusting the number of PDCCH candidates monitored in each slot using a first upper limit value, wherein if the number of PDCCH candidates configured for a slot exceeds the first upper limit value, at least some of the PDCCH candidates configured for that slot are dropped to set the number of PDCCH candidates monitored in that slot, and if the number of PDCCH candidates configured for a slot does not exceed the first upper limit value, adjusting the number of PDCCH candidates monitored in that slot. adjusting the number of PDCCH candidates monitored in the plurality of slots using a second upper limit value, wherein if a total number of PDCCH candidates adjusted based on the first upper limit value for the plurality of slots exceeds the second upper limit value, dropping at least some of the PDCCH candidates adjusted for at least one slot to set the number of PDCCH candidates monitored in the plurality of slots; and if a total number of PDCCH candidates set based on the first upper limit value for the plurality of slots does not exceed the second upper limit value, not dropping the PDCCH candidates adjusted based on the first upper limit value and setting the number of PDCCH candidates adjusted based on the first upper limit value for the plurality of slots.

[0008] (2) Furthermore, the PDCCH candidates whose number is adjusted based on the first upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling, and the PDCCH candidates whose number is adjusted based on the second upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling and PDCCH candidates that use a DCI format for multi-slot scheduling.

[0009] (3) A second aspect of the present invention is a base station device including a processor and a memory for storing computer program code, the base station device transmitting RRC signaling indicating a configuration of a search area including at least a period, an offset, and the number of PDCCH candidates for each aggregation level, the configuration of the search area including a plurality of search area configurations; configuring PDCCH candidates for each slot to a terminal device based on the RRC signaling indicating the configuration of the plurality of search areas; and determining the number of PDCCH candidates monitored in each slot using a first upper limit value in the terminal device, wherein if the number of PDCCH candidates configured for a slot exceeds the first upper limit value, at least a portion of the PDCCH candidates configured for that slot are dropped to determine the number of PDCCH candidates monitored in that slot; and if the number of PDCCH candidates configured for a slot does not exceed the first upper limit value, and performing operations including: determining the number of PDCCH candidates to be monitored in the slot without dropping the PDCCH candidates configured for that slot; determining the number of PDCCH candidates to be monitored in multiple slots using a second upper limit value in the terminal device, wherein if the total number of PDCCH candidates determined based on the first upper limit value for multiple slots exceeds the second upper limit value, dropping at least some of the PDCCH candidates determined for at least one slot to determine the number of PDCCH candidates to be monitored in the multiple slots; and if the total number of PDCCH candidates set based on the first upper limit value for multiple slots does not exceed the second upper limit value, not dropping the PDCCH candidates determined based on the first upper limit value and determining the number of PDCCH candidates determined based on the first upper limit value for multiple slots.

[0010] (4) Furthermore, the PDCCH candidates whose number is determined based on the first upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling, and the PDCCH candidates whose number is determined based on the second upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling and PDCCH candidates that use a DCI format for multi-slot scheduling.

[0011] (5) A third aspect of the present invention is a communication method used in a terminal device, comprising: a step of receiving RRC signaling indicating a configuration of a search area including at least a period, an offset, and a number of PDCCH candidates for each aggregation level; a step of configuring PDCCH candidates for each slot based on the RRC signaling indicating the configuration of the search area; and a step of adjusting the number of PDCCH candidates monitored in each slot using a first upper limit value, wherein if the number of PDCCH candidates configured for a slot exceeds the first upper limit value, at least a part of the PDCCH candidates configured for that slot are dropped to set the number of PDCCH candidates monitored in that slot; and if the number of PDCCH candidates configured for a slot does not exceed the first upper limit value, the number of PDCCH candidates configured for that slot is adjusted. adjusting the number of PDCCH candidates monitored in multiple slots using a second upper limit value, wherein, if a total number of PDCCH candidates adjusted based on the first upper limit value for multiple slots exceeds the second upper limit value, dropping at least some of the PDCCH candidates adjusted for at least one slot and setting the number of PDCCH candidates monitored in the multiple slots; and, if a total number of PDCCH candidates set based on the first upper limit value for multiple slots does not exceed the second upper limit value, not dropping the PDCCH candidates adjusted based on the first upper limit value and setting the number of PDCCH candidates adjusted based on the first upper limit value for multiple slots.

[0012] (6) Furthermore, the PDCCH candidates whose number is adjusted based on the first upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling, and the PDCCH candidates whose number is adjusted based on the second upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling and PDCCH candidates that use a DCI format for multi-slot scheduling.

[0013] (7) A fourth aspect of the present invention is a communication method used in a base station device, the method comprising the steps of: transmitting RRC signaling indicating a configuration of a search area including at least a period, an offset, and a number of PDCCH candidates for each aggregation level; configuring PDCCH candidates for each slot to a terminal device based on the RRC signaling indicating the configuration of the plurality of search areas; and determining the number of PDCCH candidates to be monitored in each slot using a first upper limit value in the terminal device, wherein if the number of PDCCH candidates configured for a slot exceeds the first upper limit value, dropping at least a portion of the PDCCH candidates configured for that slot to determine the number of PDCCH candidates to be monitored in that slot; and if the number of PDCCH candidates configured for a slot does not exceed the first upper limit value, dropping at least a portion of the PDCCH candidates configured for that slot to determine the number of PDCCH candidates to be monitored in that slot. and determining the number of PDCCH candidates monitored in a slot by using a second upper limit value in the terminal device, wherein, if the total number of PDCCH candidates determined based on the first upper limit value for a plurality of slots exceeds the second upper limit value, dropping at least some of the PDCCH candidates determined for at least one slot to determine the number of PDCCH candidates monitored in the plurality of slots, and if the total number of PDCCH candidates determined based on the first upper limit value for a plurality of slots does not exceed the second upper limit value, not dropping the PDCCH candidates determined based on the first upper limit value, and determining the number of PDCCH candidates determined based on the first upper limit value for a plurality of slots.

[0014] (8) Furthermore, the PDCCH candidates whose number is determined based on the first upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling, and the PDCCH candidates whose number is determined based on the second upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling and PDCCH candidates that use a DCI format for multi-slot scheduling. [Effects of the Invention]

[0015] According to one aspect of the present invention, it is possible to realize efficient communication between a terminal device and a base station device while suppressing the processing load on the terminal device. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a conceptual diagram of a wireless communication system according to an aspect of the present embodiment. [Figure 2] 10 is an example showing the relationship between Nslot symb, subcarrier spacing setting μ, slot setting, and CP setting according to one aspect of the present embodiment. [Figure 3] 1 is a diagram illustrating an example of a configuration of a radio frame, a subframe, and a slot according to an aspect of the present embodiment. [Figure 4] FIG. 2 is a schematic diagram illustrating an example of a resource grid in a subframe according to an aspect of the present embodiment. [Figure 5] 1 is a schematic block diagram showing a configuration of a terminal device 1 according to an aspect of the present embodiment. [Figure 6] FIG. 2 is a schematic block diagram illustrating a configuration of a base station device 3 according to one aspect of the present embodiment. [Figure 7] FIG. 10 is a diagram illustrating an example of the number of PDCCH candidates configured for each slot according to one aspect of the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an embodiment of the present invention will be described.

[0018] "A and / or B" may be a term that includes "A", "B", or "A and B".

[0019] 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 upper layer parameter may be a single upper layer parameter. The upper layer parameter may be an information element (IE) including multiple parameters.

[0020] Fig. 1 is a conceptual diagram of a wireless communication system according to one aspect of the present embodiment. In Fig. 1, the wireless communication system includes terminal devices 1A to 1C and base station devices 3A to 3B. Hereinafter, the terminal devices 1A to 1C will also be referred to as terminal devices 1 (UE). Hereinafter, the base station devices 3A to 3B will also be referred to as base station devices 3 (gNB or eNB).

[0021] The base station device 3 may be configured to include one or both of an MCG (Master Cell Group) and an SCG (Secondary Cell Group). The MCG is a group of serving cells including at least a PCell (Primary Cell). The SCG is a group of serving cells including at least a PSCell (Primary Secondary Cell). The PCell may be a serving cell provided based on an initial connection. The MCG may be configured to include one or more SCells (Secondary Cells). The SCG may be configured to include one or more SCells. The serving cell identity is a short identifier for identifying a serving cell. The serving cell identity may be provided by a higher layer parameter.

[0022] For example, base station device 3A and base station device 3B communicate with terminal device 1 using the same frequency (carrier). For example, base station device 3A and base station device 3B communicate with terminal device 1 using different frequencies (carriers). For example, base station device 3A communicates with terminal device 1 using the same frequency (carrier) as base station device 3B and a different frequency (carrier). For example, a frequency in a frequency band that requires a license is used. For example, a frequency in a frequency band that does not require a license is used.

[0023] The frame structure will be explained below.

[0024] In a wireless communication system according to an aspect of the present embodiment, at least Orthogonal Frequency Division Multiplexing (OFDM) is used. An OFDM symbol is a time domain unit of OFDM. The OFDM symbol includes at least one or more subcarriers. The OFDM symbol may be converted into a time-continuous signal in baseband signal generation.

[0025] The subcarrier spacing (SCS) is Δf=2 μ For example, the subcarrier spacing configuration μ may be set to 0, 1, 2, 3, 4, 5, or 6. For example, the subcarrier spacing may be 15 kHz, 30 kHz, 60 kHz, 120 kHz, 240 kHz, 480 kHz, or 960 kHz. For a certain BWP (BandWidth Part), the subcarrier spacing configuration μ may be given by a higher layer parameter.

[0026] In the wireless communication system according to one aspect of the present embodiment, a time unit T is used to express a length in the time domain. c The time unit T c is T c =1 / (Δfmax N f ) may be given by Δf max may be the maximum value of the subcarrier spacing supported in the wireless communication system according to one aspect of the present embodiment. max is Δf max = 480 kHz. f is N f = 4096. The constant κ can be expressed as κ = Δf max N f / (Δf ref N f,ref )=64. Δf ref may be 15 kHz. f,ref may be 2048.

[0027] The constant κ is the reference subcarrier spacing and T c The constant κ may be used for the length of the subframe. The number of slots included in the subframe may be determined based at least on the constant κ. ref is the reference subcarrier spacing, and N f,ref is a value corresponding to the reference subcarrier spacing.

[0028] Downlink transmission and / or uplink transmission is configured with a 10 ms frame. A frame is configured to include 10 subframes. The length of a subframe is 1 ms. The frame length may be given regardless of the subcarrier spacing Δf. That is, the frame setting may be given regardless of μ. The subframe length may be given regardless of the subcarrier spacing Δf. That is, the subframe setting may be given regardless of μ.

[0029] For a given subcarrier spacing setting μ, the number and index of slots contained in the subframe may be given. For example, the first slot number n μ s is from 0 to N within the subframe. subframe,μ slotThe subcarrier spacing μ may be given in ascending order from -1 to 1. For the subcarrier spacing μ, the number of slots included in the frame and their index may be given. For example, the second slot number n μ s,f is the number of frames from 0 to N frame,μ slot -1. slot symb N OFDM symbols may be included in one slot. slot symb may be given based at least on a slot configuration and / or a part or all of a cyclic prefix (CP) configuration. The slot configuration may be given by at least a higher layer parameter tdd-UL-DL-ConfigurationCommon. The CP configuration may be given based at least on higher layer parameters. The CP configuration may be given based at least on dedicated RRC signaling. The first slot number and the second slot number are also referred to as slot numbers (slot indexes).

[0030] FIG. 2 shows an N slot symb 2A is an example showing the relationship between the subcarrier spacing setting μ, the slot setting, and the CP setting. In FIG. 2A, when the slot setting is 0, the subcarrier spacing setting μ is 2, and the CP setting is normal cyclic prefix (CP), N slot symb =14, N frame,μ slot =40, N subframe,μ slot In addition, in FIG. 2B, when the slot setting is 0, the subcarrier spacing setting μ is 2, and the CP setting is extended cyclic prefix (CP), N slot symb =12, N frame,μ slot =40, N subframe,μ slot = 4. N in slot setting 0slot symb is N in slot setting 1 slot symb It may correspond to twice the amount.

[0031] A common subcarrier spacing setting, slot setting, and CP setting may be performed for each cell, or a different subcarrier spacing setting, slot setting, and CP setting may be performed for each cell in terminal device 1. A common subcarrier spacing setting, slot setting, and CP setting may be performed for base station device 3A and base station device 3B, or a different subcarrier spacing setting, slot setting, and CP setting may be performed.

[0032] 3 is an example showing the configuration of a radio frame, a subframe, and a slot according to an aspect of the present embodiment. In the example shown in FIG. 3, the length of a slot is 0.5 ms, the length of a subframe is 1 ms, and the length of a radio frame is 10 ms. A slot may be a unit of resource allocation in the time domain. For example, a slot may be a unit to which one transport block is mapped. For example, a transport block may be mapped to one slot. Here, a transport block may be a unit of data transmitted within a predetermined interval (e.g., a transmission time interval (TTI)) defined in a higher layer (e.g., Media Access Control (MAC), Radio Resource Control (RRC)).

[0033] For example, the length of a slot may be determined by the number of OFDM symbols. For example, the number of OFDM symbols may be 7 or 14. The length of a slot may be determined based at least on the length of an OFDM symbol. The length of an OFDM symbol may vary based at least on the subcarrier spacing. Furthermore, the length of an OFDM symbol may be determined based at least on the number of points of a Fast Fourier Transform (FFT) used to generate the OFDM symbol. Furthermore, the length of an OFDM symbol may include the length of a cyclic prefix (CP) added to the OFDM symbol. Here, an OFDM symbol may be referred to as a symbol. Furthermore, when a communication method other than OFDM is used in communication between the terminal device 1 and the base station device 3 (for example, when SC-FDMA or DFT-s-OFDM is used), the generated SC-FDMA symbol and / or DFT-s-OFDM symbol is also referred to as an OFDM symbol. Unless otherwise specified, OFDM includes SC-FDMA or DFT-s-OFDM.

[0034] For example, the slot length may be 0.0078125 ms, 0.03125 ms, 0.125 ms, 0.25 ms, 0.5 ms, or 1 ms. For example, if the subcarrier spacing is 15 kHz, the slot length may be 1 ms. For example, if the subcarrier spacing is 30 kHz, the slot length may be 0.5 ms. For example, if the subcarrier spacing is 120 kHz, the slot length may be 0.125 ms. For example, if the subcarrier spacing is 480 kHz, the slot length may be 0.03125 ms. For example, if the subcarrier spacing is 960 kHz, the slot length may be 0.0078125 ms. For example, if the slot length is 0.0078125 ms, one subframe may consist of 128 slots. For example, if the slot length is 0.03125 ms, one subframe may consist of 32 slots. For example, if the slot length is 0.125 ms, one subframe may consist of 8 slots. For example, if the slot length is 0.25 ms, one subframe may consist of four slots. For example, if the slot length is 0.5 ms, one subframe may consist of two slots. For example, if the slot length is 1 ms, one subframe may consist of one slot.

[0035] Here, OFDM includes a multi-carrier communication method to which pulse shaping, PAPR reduction, out-of-band emission reduction, filtering, and / or phase processing (e.g., phase rotation) are applied. The multi-carrier communication method may be a communication method for generating / transmitting a signal in which multiple subcarriers are multiplexed.

[0036] A radio frame may be given by the number of subframes. The number of subframes for a radio frame may be, for example, 10. A radio frame may be given by the number of slots.

[0037] A common radio frame configuration, subframe configuration, and slot configuration may be set for each cell in the terminal device 1, or a different radio frame configuration, subframe configuration, and slot configuration may be set for each cell. A common radio frame configuration, subframe configuration, and slot configuration may be set for the base station device 3A and the base station device 3B, or different radio frame configurations, subframe configurations, and slot configurations may be set.

[0038] The physical resources will be explained below.

[0039] An antenna port is defined by whether the channel through which symbols are transmitted at one antenna port can be estimated from the channel through which other symbols are transmitted at the same antenna port. If the large-scale properties of the channel through which symbols are transmitted at one antenna port can be estimated from the channel through which symbols are transmitted at another antenna port, the two antenna ports are said to be Quasi Co-Located (QCL). The large-scale properties may include at least long-range channel properties. The large-scale properties may include at least some or all of delay spread, Doppler spread, Doppler shift, average gain, average delay, and spatial Rx parameters. The first and second antenna ports are QCL in terms of beam parameters when the receive beam assumed by the receiver for the first antenna port is the same as the receive beam assumed by the receiver for the second antenna port. The first antenna port and the second antenna port being QCLs in terms of beam parameters may mean that the transmission beam assumed by the receiving side for the first antenna port and the transmission beam assumed by the receiving side for the second antenna port are the same. The terminal device 1 may assume that the two antenna ports are QCLs if the large-scale characteristics of a channel through which symbols are transmitted at one antenna port can be estimated from the channel through which symbols are transmitted at another antenna port. The two antenna ports being QCLs may mean that the two antenna ports are assumed to be QCLs.

[0040] For each subcarrier spacing configuration and set of carriers, N μ RB,x N RB sc subcarriers and N (μ) symb N subframe,μsymb Given a resource grid of N OFDM symbols, μ RB,x may denote the number of resource blocks provided for the subcarrier spacing setting μ for carrier x. μ RB,x may be the maximum number of resource blocks given for the subcarrier spacing setting μ for carrier x. Carrier x may indicate either a downlink carrier or an uplink carrier, i.e., x may be “DL” or “UL”. N μ RB is N μ RB,DL , and / or N μ RB,UL It is a name that includes. RB sc may indicate the number of subcarriers included in one resource block. At least one resource grid may be provided for each antenna port p and / or for each subcarrier spacing setting μ and / or for each transmission direction setting. The transmission direction includes at least the downlink (DL) and the uplink (UL). Hereinafter, a set of parameters including at least the antenna port p, the subcarrier spacing setting μ, and some or all of the transmission direction settings is also referred to as a first radio parameter set. In other words, one resource grid may be provided for each first radio parameter set.

[0041] In the downlink, a carrier included in a serving cell is called a downlink carrier (or a downlink component carrier). In the uplink, a carrier included in a serving cell is called an uplink carrier (or an uplink component carrier). Downlink component carriers and uplink component carriers are collectively called component carriers (or carriers).

[0042] Each element in the resource grid given for each first radio parameter set is called a resource element. A resource element is a frequency domain index k sc and the time domain index l sym For a given first radio parameter set, the resource elements are identified by frequency domain index k sc and the time domain index l sym The frequency domain index k is specified by sc and the time domain index l sym The resource element identified by sc , l sym ) is also called the frequency domain index k sc is from 0 to N μ RB N RB sc -1. μ RB may be the number of resource blocks given the subcarrier spacing setting μ. RB sc is the number of subcarriers contained in the resource block, and N RB sc = 12. The frequency domain index k sc is the subcarrier index k sc The time domain index l sym is the OFDM symbol index l sym It may correspond to.

[0043] 4 is a schematic diagram illustrating an example of a resource grid in a subframe according to one aspect of this embodiment. In the resource grid of FIG. 4, the horizontal axis represents the time domain index l sym and the vertical axis is the frequency domain index k sc In one subframe, the frequency domain of the resource grid is N μ RB N RB scIn one subframe, the time domain of the resource grid is 14 2 μ One resource block may contain N OFDM symbols. RB sc The resource block may include subcarriers. The time domain of the resource block may correspond to one OFDM symbol. The time domain of the resource block may correspond to 14 OFDM symbols. The time domain of the resource block may correspond to one or more slots. The time domain of the resource block may correspond to one subframe.

[0044] FIG. 4 shows an example of a resource grid in one cell.

[0045] The terminal device 1 may be instructed to transmit and receive using only a subset of the resource grid. The subset of the resource grid is also referred to as a BWP, and the BWP may be given based at least on upper layer parameters and / or part or all of the DCI. The BWP is also referred to as a band part (BP: Bandwidth Part). In other words, the terminal device 1 may not be instructed to transmit and receive using the entire set of the resource grid. In other words, the terminal device 1 may be instructed to transmit and receive using some frequency resources in the resource grid. One BWP may be composed of multiple resource blocks in the frequency domain. One BWP may be composed of multiple contiguous resource blocks in the frequency domain. A BWP set for a downlink carrier is also referred to as a downlink BWP. A BWP set for an uplink carrier is also referred to as an uplink BWP.

[0046] One or more downlink BWPs may be configured for the terminal device 1. The terminal device 1 may attempt to receive a physical channel (e.g., PDCCH, PDSCH, SS / PBCH, etc.) in one of the one or more downlink BWPs. The one downlink BWP is also referred to as an activated downlink BWP.

[0047] One or more uplink BWPs may be configured for the terminal device 1. The terminal device 1 may attempt to transmit a physical channel (e.g., PUCCH, PUSCH, PRACH, etc.) in one of the one or more uplink BWPs. The one uplink BWP is also referred to as an activated uplink BWP.

[0048] A set of downlink BWPs may be configured for each serving cell. The set of downlink BWPs may include one or more downlink BWPs. A set of uplink BWPs may be configured for each serving cell. The set of uplink BWPs may include one or more uplink BWPs.

[0049] The higher layer parameters are parameters included in higher layer signals. The higher layer signals may be RRC (Radio Resource Control) signaling or MAC CE (Medium Access Control Control Element). Here, the higher layer signals may be RRC layer signals or MAC layer signals.

[0050] The higher layer signal may be common RRC signaling. The common RRC signaling may include at least some or all of the following features C1 to C3. Feature C1) Mapped to BCCH logical channel or CCCH logical channel Feature C2) Includes at least the radioResourceConfigCommon information element Feature C3) Mapped to PBCH

[0051] The radioResourceConfigCommon information element may include information indicating a configuration commonly used in the serving cell. The configuration commonly used in the serving cell may include at least a PRACH configuration. The PRACH configuration may at least indicate one or more random access preamble indices. The PRACH configuration may at least indicate a time / frequency resource for the PRACH.

[0052] The higher layer signaling may be dedicated RRC signaling. The dedicated RRC signaling may have at least some or all of the following features D1 to D2: Feature D1) Mapped to DCCH logical channel Feature D2) At least the radioResourceConfigDedicated information element is included

[0053] The radioResourceConfigDedicated information element may include at least information indicating a setting specific to the terminal device 1. The radioResourceConfigDedicated information element may include at least information indicating a setting of a BWP. The setting of the BWP may indicate at least a frequency resource of the BWP.

[0054] For example, the MIB, the first system information, and the second system information may be included in common RRC signaling. Also, an upper layer message that is mapped to a DCCH logical channel and includes at least the radioResourceConfigCommon information element may be included in common RRC signaling. Also, an upper layer message that is mapped to a DCCH logical channel and does not include the radioResourceConfigCommon information element may be included in dedicated RRC signaling. Also, an upper layer message that is mapped to a DCCH logical channel and includes at least the radioResourceConfigDedicated information element may be included in dedicated RRC signaling.

[0055] The first system information may at least indicate a time index of an SS (Synchronization Signal) block. The SS block is also referred to as an SS / PBCH block. The SS / PBCH block is also referred to as an SS / PBCH. The first system information may include at least information related to PRACH resources. The first system information may include at least information related to setting up an initial connection. The second system information may be system information other than the first system information.

[0056] The radioResourceConfigDedicated information element may include at least information related to PRACH resources. The radioResourceConfigDedicated information element may include at least information related to setting up an initial connection.

[0057] The following describes physical channels and physical signals according to various aspects of the present embodiment.

[0058] An uplink physical channel may correspond to a set of resource elements carrying information generated in a higher layer. An uplink physical channel is a physical channel used in an uplink carrier. In a wireless communication system according to one 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)

[0059] The PUCCH may be used to transmit uplink control information (UCI). The uplink control information includes some or all of channel state information (CSI), a scheduling request (SR), and a hybrid automatic repeat request ACKnowledgement (HARQ-ACK) corresponding to a transport block (TB, MAC PDU, DL-SCH, PDSCH). Note that the uplink control information may include information not listed above.

[0060] The HARQ-ACK may include at least a HARQ-ACK bit (HARQ-ACK information) corresponding to at least one transport block. The HARQ-ACK bit may indicate an acknowledgement (ACK) or a negative acknowledgement (NACK) corresponding to one or more transport blocks. The HARQ-ACK may include at least a HARQ-ACK codebook including one or more HARQ-ACK bits. The HARQ-ACK bit corresponding to one or more transport blocks may correspond to a PDSCH including the one or more transport blocks. The HARQ-ACK bit may indicate an ACK or a NACK corresponding to one Code Block Group (CBG) included in the transport block.

[0061] A scheduling request (SR) may be used at least to request PUSCH resources for initial transmission. A scheduling request bit may be used to indicate either a positive SR or a negative SR. The scheduling request bit indicating a positive SR is also referred to as "a positive SR is transmitted." A positive SR may indicate that PUSCH resources for initial transmission are requested by the terminal device 1. A positive SR may indicate that a scheduling request is triggered by a higher layer. A positive SR may be transmitted when transmission of a scheduling request is instructed by a higher layer. The scheduling request bit indicating a negative SR is also referred to as "a negative SR is transmitted." A negative SR may indicate that PUSCH resources for initial transmission are not requested by the terminal device 1. A negative SR may indicate that a scheduling request is not triggered by a higher layer. A negative SR may be transmitted when transmission of a scheduling request is not instructed by a higher layer.

[0062] The channel state information may include at least some or all of a Channel Quality Indicator (CQI), a Precoder Matrix Indicator (PMI), and a Rank Indicator (RI). The CQI is an indicator related to the quality of the channel (e.g., propagation strength), the PMI is an indicator indicating the precoder, and the RI is an indicator indicating the transmission rank (or the number of transmission layers).

[0063] The PUCCH may support one or more PUCCH formats (for example, PUCCH format 0 to PUCCH format 4). The PUCCH format may be mapped to the PUCCH and transmitted. The PUCCH format may be transmitted on the PUCCH. Transmission of the PUCCH format may also mean transmission of the PUCCH.

[0064] The PUSCH is used at least to transmit transport blocks (TB, MAC PDU, UL-SCH, PUSCH). The PUSCH may be used at least to transmit some or all of the transport blocks, HARQ-ACK, channel state information, and scheduling requests. The PUSCH is used at least to transmit random access messages 3. The PUSCH may also be used to transmit information not listed above.

[0065] The PRACH is used at least to transmit a random access preamble (random access message 1). The PRACH may be used at least to indicate some or all of an initial connection establishment procedure, a handover procedure, a connection re-establishment procedure, synchronization (timing adjustment) for PUSCH transmission, and a request for resources for the PUSCH. The random access preamble may be used to notify the base station device 3 of an index (random access preamble index) provided by a higher layer of the terminal device 1.

[0066] In Figure 1, the following uplink physical signals are used in uplink wireless communication: The uplink physical signals may not be used to transmit information output from higher layers, but are used by the physical layer. ·UL DMRS(UpLink Demodulation Reference Signal) ·SRS(Sounding Reference Signal) ·UL PTRS(UpLink Phase Tracking Reference Signal)

[0067] The UL DMRS is related to the transmission of the PUSCH and / or the PUCCH. The UL DMRS is multiplexed with the PUSCH or the PUCCH. The base station device 3 may use the UL DMRS to perform propagation path correction for the PUSCH or the PUCCH. Hereinafter, transmitting a PUSCH together with an UL DMRS related to the PUSCH is simply referred to as transmitting a PUSCH. Hereinafter, transmitting a PUCCH together with an UL DMRS related to the PUCCH is simply referred to as transmitting a PUCCH. The UL DMRS related to the PUSCH is also referred to as an UL DMRS for the PUSCH. The UL DMRS related to the PUCCH is also referred to as an UL DMRS for the PUCCH.

[0068] The SRS may not be related to the transmission of the PUSCH or the PUCCH. The base station device 3 may use the SRS to measure the channel condition. The SRS may be transmitted at the end of a subframe in an uplink slot or within a predetermined number of OFDM symbols from the end.

[0069] The UL PTRS may be a reference signal used at least for phase tracking. The UL PTRS may be associated with a UL DMRS group including at least antenna ports used for one or more UL DMRSs. The association of the UL PTRS with the UL DMRS group may be such that the antenna port of the UL PTRS and some or all of the antenna ports included in the UL DMRS group are at least QCL. The UL DMRS group may be identified based at least on the antenna port with the smallest index among the UL DMRSs included in the UL DMRS group. The UL PTRS may be mapped to the antenna port with the smallest index among one or more antenna ports to which a single codeword is mapped. The UL PTRS may be mapped to a first layer when a single codeword is mapped to at least a first layer and a second layer. The UL PTRS may not be mapped to the second layer. The index of the antenna port to which the UL PTRS is mapped may be determined based at least on downlink control information.

[0070] Note that an uplink physical signal not described above may also be used.

[0071] 1, the following downlink physical channels are used in downlink wireless communication from the base station device 3 to the terminal device 1. The downlink physical channels are used by the physical layer to transmit information output from higher layers. ·PBCH(Physical Broadcast Channel) ·PDCCH (Physical Downlink Control Channel) ·PDSCH(Physical Downlink Shared Channel)

[0072] The PBCH is used at least to transmit a Master Information Block (MIB, BCH, Broadcast Channel). The PBCH may be transmitted based on a predetermined transmission interval. The PBCH may be transmitted at intervals of 80 ms. The PBCH may be transmitted at intervals of 160 ms. The content of the information included in the PBCH may be updated every 80 ms. Some or all of the information included in the PBCH may be updated every 160 ms. The PBCH may be composed of 288 subcarriers. The PBCH may be composed of 2, 3, or 4 OFDM symbols. The MIB may include information related to an identifier (index) of the synchronization signal. The MIB may include information indicating at least a portion of the slot number, subframe number, and / or radio frame number in which the PBCH is transmitted.

[0073] The PDCCH is used at least for transmitting downlink control information (DCI). The PDCCH may be transmitted including at least the downlink control information. The PDCCH may include the downlink control information. The downlink control information is also referred to as a DCI format. The downlink control information may include at least either a downlink grant (DL grant) or an uplink grant (UL grant). The DCI format used for scheduling the PDSCH is also referred to as a downlink DCI format. The DCI format used for scheduling the PUSCH is also referred to as an uplink DCI format. The downlink grant is also referred to as a downlink assignment (DL assignment) or a downlink allocation (DL allocation). The uplink DCI format includes at least one or both of DCI format 0_0 and DCI format 0_1.

[0074] DCI format 0_0 is configured to include at least some or all of 1A to 1F. 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 (Modulation and Coding Scheme field) 1F) CSI request field

[0075] The DCI format specification field may be used at least to indicate to which of one or more DCI formats the DCI format including the DCI format specification field corresponds, and the one or more DCI formats may be given based at least on some or all of DCI format 1_0, DCI format 1_1, DCI format 0_0, and / or DCI format 0_1.

[0076] The frequency domain resource allocation field may be used at least to indicate allocation of frequency resources for a PUSCH scheduled by a DCI format including the frequency domain resource allocation field. The frequency domain resource allocation field is also referred to as a Frequency Domain Resource Allocation (FDRA) field.

[0077] The time domain resource allocation field may be used at least to indicate the allocation of time resources for a PUSCH scheduled by a DCI format including the time domain resource allocation field.

[0078] The frequency hopping flag field may be used at least to indicate whether frequency hopping is applied to a PUSCH scheduled by a DCI format including the frequency hopping flag field.

[0079] The MCS field may be used to indicate at least a part or all of a modulation scheme and / or a target coding rate for a PUSCH scheduled by a DCI format including the MCS field. The target coding rate may be a target coding rate for a transport block of the PUSCH. The size of the transport block (TBS) may be determined based at least on the target coding rate.

[0080] The CSI request field is at least used to indicate CSI reporting. The size of the CSI request field may be a predetermined value. The size of the CSI request field may be 0, 1, 2, or 3.

[0081] DCI format 0_1 ​​is configured to include at least some or all of 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)

[0082] The UL DAI field is at least used to indicate the transmission status of the PDSCH. When a 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 in the PUSCH. The UL DAI field indicates the number of HARQ-ACKs included in the HARQ-ACK codebook transmitted in the PUSCH. The UL DAI field indicates the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted in the PUSCH. The UL DAI field indicates the number of PDSCHs and SPS releases in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted in the PUSCH.

[0083] The UL DAI field may indicate a value to which modulo arithmetic has been applied. An example in which the UL DAI field is 2 bits will be described. When the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is 0, the UL DAI field indicates "00". When the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is 1, the UL DAI field indicates "01". When the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is 2, the UL DAI field indicates "10". When the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is 3, the UL DAI field indicates "11". When the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is four, the UL DAI field indicates "00". When the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is five, the UL DAI field indicates "01". When the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is six, the UL DAI field indicates "10". When the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is seven, the UL DAI field indicates "11". In this example, a modulo operation using the value '4' is performed on the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH.

[0084] The terminal device 1 interprets the UL DAI field taking into account the total number of received PDSCHs. For example, the terminal device 1 receives four PDSCHs and receives a UL DAI field indicating "00". In this case, the terminal device 1 interprets that the number of PDSCHs in which the corresponding HARQ-ACKs are included in the HARQ-ACK codebook transmitted on the PUSCH indicated by the UL DAI field is four. For example, the terminal device 1 receives three PDSCHs and receives a UL DAI field indicating "00". In this case, the terminal device 1 interprets that the number of PDSCHs in which the corresponding HARQ-ACKs are included in the HARQ-ACK codebook transmitted on the PUSCH indicated by the UL DAI field is four, and determines that reception of one PDSCH has been missed.

[0085] The BWP field may be used to indicate the uplink BWP to which the PUSCH scheduled by DCI format 0_1 ​​is mapped.

[0086] The CSI request field is at least used to indicate CSI reporting, and the size of the CSI request field may be determined based at least on a higher layer parameter ReportTriggerSize.

[0087] The downlink DCI formats include at least one or both of DCI format 1_0 and DCI format 1_1.

[0088] DCI format 1_0 is configured to include at least some or all of 3A to 3H. 3A) Identifier for DCI formats field 3B) Frequency domain resource assignment field 3C) Time domain resource assignment field 3D) Frequency hopping flag field 3E) MCS field (Modulation and Coding Scheme field) 3F) First CSI request field 3G) PDSCH-to-HARQ feedback timing indicator field 3H) PUCCH resource indicator field

[0089] The timing indication field from the PDSCH to the HARQ feedback may be a field indicating timing K1. When the index of the slot including the last OFDM symbol of the PDSCH is slot n, the index of the slot including a PUCCH or a PUSCH including at least a HARQ-ACK corresponding to a transport block included in the PDSCH may be n+K1. When the index of the slot including the last OFDM symbol of the PDSCH is slot n, the index of the slot including the first OFDM symbol of the PUCCH or the first OFDM symbol of the PUSCH including at least a HARQ-ACK corresponding to a transport block included in the PDSCH may be n+K1.

[0090] Hereinafter, the PDSCH-to-HARQ feedback timing indicator field may be referred to as an HARQ indication field.

[0091] The PUCCH resource indication field may be a field indicating the index of one or more PUCCH resources included in the PUCCH resource set.

[0092] DCI format 1_1 is configured to include at least some or all of 4A to 4J. 4A) Identifier for DCI formats field 4B) Frequency domain resource assignment field 4C) Time domain resource assignment field 4D) Frequency hopping flag field 4E) MCS field (Modulation and Coding Scheme field) 4F) First CSI request field 4G) PDSCH-to-HARQ feedback timing indicator field 4H) PUCCH resource indicator field 4J) BWP field

[0093] The BWP field may be used to indicate the downlink BWP to which the PDSCH scheduled by DCI format 1_1 is mapped.

[0094] DCI format 2_0 may be configured to include at least one or more Slot Format Indicators (SFIs).

[0095] The downlink control information may include a slot format indicator (SFI). A pattern indicating whether each subframe (slot) among a plurality of subframes (slots) is an uplink subframe (slot), a downlink subframe (slot), or a flexible subframe (slot) may be transmitted and received using the downlink control information. The terminal device 1 may determine that a subframe (slot) not indicated by the received SFI is a flexible subframe (slot). When PUSCH transmission is scheduled for a flexible subframe (slot) by a UL grant, the terminal device 1 processes the flexible subframe (slot) as an uplink subframe (slot). When PUSCH transmission is not scheduled for a flexible subframe (slot) by a UL grant, the terminal device 1 monitors PDCCH candidates in the flexible subframe (slot) and performs processing to detect DL assignment. When reception of a PDSCH is scheduled by DL assignment in a flexible subframe (slot), the terminal device 1 performs processing using the flexible subframe (slot) as a downlink subframe (slot).

[0096] For example, downlink control information including a downlink grant or an uplink grant is transmitted and received on a PDCCH, including a C-RNTI (Cell-Radio Network Temporary Identifier).

[0097] In the downlink DCI format, DCI format 1_0 may use a first format (first type downlink DCI format) including scheduling information for one PDSCH, or a second format (second type downlink DCI format) including scheduling information for multiple (e.g., two) PDSCHs. In the downlink DCI format, DCI format 1_1 may use a first format including scheduling information for one PDSCH, or a second format including scheduling information for multiple (e.g., two) PDSCHs. For example, the first format includes one frequency-domain resource allocation field, one time-domain resource allocation field, and one MCS field. For example, the second format includes multiple (e.g., two) frequency-domain resource allocation fields, multiple (e.g., two) time-domain resource allocation fields, and multiple (e.g., two) MCS fields.

[0098] In various aspects of the present embodiment, unless otherwise specified, the number of resource blocks refers to the number of resource blocks in the frequency domain.

[0099] A downlink grant may be used at least for scheduling one PDSCH in one serving cell. A downlink grant may be used at least for scheduling multiple PDSCHs in one serving cell. A downlink grant may be used at least for scheduling multiple PDSCHs in multiple serving cells. A downlink grant may be used at least for scheduling a PDSCH in the same slot as the slot in which the downlink grant is transmitted. A downlink grant may be used at least for scheduling a PDSCH in a slot different from the slot in which the downlink grant is transmitted. An uplink grant may be used at least for scheduling one PUSCH in one serving cell. An uplink grant may be used at least for scheduling multiple PUSCHs in one serving cell. An uplink grant may be used at least for scheduling multiple PUSCHs in multiple serving cells.

[0100] Note that various DCI formats may further include fields different from the above-mentioned fields. They may include a field indicating the cumulative number of transmitted PDCCHs (C-DAI: Counter Downlink Assignment Index field), or a field indicating the total number of transmitted PDCCHs (T-DAI: Total Downlink Assignment Index field).

[0101] The value of K1 (information or parameter indicated by a timing indication field from PDSCH to HARQ feedback) indicated by a DCI format included in the PDCCH may be, for example, a value among {0, 1, 2, ..., 15}. For example, the PDSCH scheduled by the DCI format is transmitted by the base station device 3 in slot n and received by the terminal device 1. The terminal device 1 may transmit (report) HARQ-ACK information corresponding to the PDSCH via the PUCCH or PUSCH in slot n+K1.

[0102] The HARQ-ACK bits (HARQ-ACK information) corresponding to the transport blocks transmitted and received in the downlink frequency band (frequency spectrum, carrier, component carrier) of the base station device 3 are transmitted and received in the uplink frequency band (frequency spectrum, carrier, component carrier) of the base station device 3 in the above-mentioned manner based on at least one of the above-mentioned various fields included in the DCI format (PDSCH-to-HARQ feedback timing indicator field, HARQ indication field, PUCCH resource indication field, C-DAI field, T-DAI field, UL DAI field).

[0103] One physical channel may be mapped to one serving cell, and one physical channel may be mapped to one BWP configured on one carrier included in one serving cell.

[0104] The terminal device 1 may be configured with one or more control resource sets (CORESET: CONTROLLER REsource SET). The terminal device 1 monitors the PDCCH in the one or more control resource sets. Here, monitoring the PDCCH in the one or more control resource sets may include monitoring one or more PDCCHs corresponding to each of the one or more control resource sets. Note that the PDCCH may include one or more PDCCH candidates and / or sets of PDCCH candidates. Furthermore, monitoring the PDCCH may include monitoring and detecting the PDCCH and / or a DCI format transmitted via the PDCCH.

[0105] The control resource set may be a time-frequency region to which one or more PDCCHs may be mapped. The control resource set may be a region in which the terminal device 1 monitors the PDCCHs. The control resource set may be configured of contiguous resources (localized resources). The control resource set may be configured of non-contiguous resources (distributed resources).

[0106] In the frequency domain, the mapping unit of the control resource set may be a resource block. For example, in the frequency domain, the mapping unit of the control resource set may be six resource blocks. In the time domain, the mapping unit of the control resource set may be an OFDM symbol. For example, in the time domain, the mapping unit of the control resource set may be one OFDM symbol.

[0107] The mapping of the control resource set to resource blocks may be based at least on higher layer parameters, which may include a bitmap for a group of resource blocks (RBG), which may be given by six consecutive resource blocks.

[0108] The number of OFDM symbols constituting the control resource set may be determined based at least on higher layer parameters. For example, the start positions of the OFDM symbols constituting the control resource set are notified from the base station device 3 to the terminal device 1 using higher layer signaling. For example, the end positions of the OFDM symbols constituting the control resource set are notified from the base station device 3 to the terminal device 1 using higher layer signaling.

[0109] A certain control resource set may be a common control resource set. The common control resource set may be a control resource set that is set in common for a plurality of terminal devices 1. The common control resource set may be given based on at least some or all of the MIB, the first system information, the second system information, the common RRC signaling, and the cell ID. For example, the time resources and / or the frequency resources of the control resource set that is set to monitor the PDCCH used for scheduling of the first system information may be given based at least on the MIB.

[0110] The control resource set configured in the MIB is also referred to as CORESET#0, which may be the control resource set with index #0.

[0111] A control resource set may be a dedicated control resource set. The dedicated control resource set may be a control resource set configured to be used exclusively for the terminal device 1. The dedicated control resource set may be assigned based on at least dedicated RRC signaling and part or all of the value of the C-RNTI. 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 an index (CCE index) may be assigned to each CCE.

[0112] A CCE may be configured to include one or more groups of REGs (Resource Element Groups). A group of REGs is also called a REG bundle. The number of REGs constituting one REG group is called the bundle size. For example, the REG bundle size may be 1, 2, 3, or 6. In interleaved mapping, an interleaver may be applied to each REG bundle. The terminal device 1 may assume that the precoders applied to REs within a group of REGs are the same. The terminal device 1 can perform channel estimation assuming that the precoders applied to REs within a group of REGs are the same. On the other hand, the terminal device 1 may assume that the precoders applied to REs between groups of REGs are not the same. In other words, the terminal device 1 does not need to assume that the precoders applied to REs between groups of REGs are the same. "Between groups of REGs" may be rephrased as "between two different groups of REGs." The terminal device 1 can perform channel estimation assuming that the precoders applied to REs between groups of REGs are not the same.

[0113] An REG may be configured by one OFDM symbol of one PRB. That is, an REG may be configured by 12 consecutive REs in the frequency domain. Some of the REs configuring an REG may be REs to which downlink control information is not mapped. An REG may be configured to include REs to which downlink control information is not mapped, or may be configured to exclude REs to which downlink control information is not mapped. An RE to which downlink control information is not mapped may be an RE to which a reference signal is mapped, an RE to which a channel other than a control channel is mapped, or an RE to which a control channel is not assumed to be mapped by the terminal device 1.

[0114] A CCE may be composed of six REGs. A CCE may be composed of REGs that are contiguously mapped (such mapping may be referred to as localized mapping) (such mapping may be referred to as non-interleaved CCE-to-REG mapping) (such mapping may be referred to as non-interleaved mapping). Note that all REGs that constitute a CCE do not necessarily need to be contiguous in the frequency domain. For example, if all of the multiple resource blocks that constitute a control resource set are not contiguous in the frequency domain, even if the numbers assigned to the REGs are contiguous, the resource blocks that constitute each REG with consecutive numbers are not contiguous in the frequency domain. If a control resource set is composed of multiple OFDM symbols and multiple REGs that constitute one CCE are arranged across multiple time intervals (OFDM symbols), a CCE may be composed of a group of REGs that are contiguously mapped.

[0115] A CCE may be composed of REGs that are mapped discontinuously (such mapping may be referred to as distributed mapping) (such mapping may be referred to as interleaved CCE-to-REG mapping) (such mapping may be referred to as interleaved mapping). REGs that constitute a CCE may be mapped discontinuously to resources in the time-frequency domain using an interleaver. When a control resource set is composed of multiple OFDM symbols and multiple REGs that constitute one CCE are arranged across multiple time intervals (OFDM symbols), a CCE may be composed of REGs that are mixed and mapped discontinuously. A CCE may be composed of REGs that are mapped in a distributed manner in units of multiple groups of REGs. A CCE may be composed of REGs that are mapped in a distributed manner in units of multiple groups of REGs.

[0116] A set of PDCCH candidates monitored by the terminal device 1 is defined in terms of a search space. That is, the set of PDCCH candidates monitored by the terminal device 1 is given by the search space.

[0117] The search space may be configured to include one or more PDCCH candidates of one or more aggregation levels. The aggregation level of the PDCCH candidate may indicate the number of CCEs that constitute the PDCCH. The PDCCH candidate may be mapped to one or more CCEs.

[0118] The number of CCEs that make up a PDCCH candidate is also called the aggregation level (AL). When one PDCCH candidate is made up of an aggregation of multiple CCEs, the PDCCH candidate is made up of multiple CCEs with consecutive CCE numbers. When the aggregation level is AL, X The set of PDCCH candidates is at aggregation level AL X In other words, the aggregation level ALX The search area of ​​is the aggregation level AL X A search space may be configured to include one or more PDCCH candidates of a plurality of aggregation levels. Also, a search space may include PDCCH candidates of a plurality of aggregation levels. For example, a CSS may include PDCCH candidates of a plurality of aggregation levels. For example, a USS may include PDCCH candidates of a plurality of aggregation levels. The set of aggregation levels of PDCCH candidates included in a CSS and the set of aggregation levels of PDCCH candidates included in a USS may be defined / configured, respectively.

[0119] The terminal device 1 may monitor at least one or more search spaces in slots where DRX (Discontinuous Reception) is not set. DRX may be provided based at least on higher layer parameters. The terminal device 1 may monitor at least one or more search space sets in slots where DRX is not set. Multiple search space sets may be configured in the terminal device 1. An index (search space set index) may be assigned to each search space set.

[0120] The 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. The search area set may be configured with one or more search areas corresponding to one or more aggregation levels.

[0121] Each search space set may be associated with at least one control resource set. Each search space set may be included in one control resource set. Each search space set may be given an index of the control resource set associated with that search space set.

[0122] The search space may be of two types: a common search space (CSS) and a UE-specific search space (USS). The CSS may be a search space set in common for multiple terminal devices 1. The USS may be a search space including settings used exclusively for an individual terminal device 1. The CSS may be given based on at least a synchronization signal, an MIB, first system information, second system information, common RRC signaling, dedicated RRC signaling, a cell ID, etc. The USS may be given based on at least a value of dedicated RRC signaling and / or a C-RNTI. The CSS may be a search space set in resources (control resource elements) common to multiple terminal devices 1. The USS may be a search space set in resources (control resource elements) for each individual terminal device 1.

[0123] The CSS may use a type 0 PDCCH CSS for a DCI format scrambled by the SI-RNTI used for transmitting system information in the primary cell, and a type 1 PDCCH CSS for a DCI format scrambled by the RA-RNTI and TC-RNTI used for initial access. The CSS may use a type PDCCH CSS for a DCI format scrambled by the CC-RNTI used for unlicensed access. The terminal device 1 can monitor PDCCH candidates in those search spaces. The DCI format scrambled by a predetermined RNTI may be a DCI format to which a CRC (Cyclic Redundancy Check) scrambled by a predetermined RNTI is added.

[0124] The information related to reception of the PDCCH may include information related to an ID indicating a destination of the PDCCH. The ID indicating a destination of the PDCCH may be an ID used for scrambling CRC bits added to the PDCCH. The ID indicating a destination of the PDCCH is also referred to as an RNTI (Radio Network Temporary Identifier). The information related to reception of the PDCCH may include information related to an ID used for scrambling CRC bits added to the PDCCH. The terminal device 1 can attempt to receive the PDCCH based at least on the information related to the ID included in the PBCH.

[0125] The RNTI may include SI-RNTI (System Information - RNTI), P-RNTI (Paging - RNTI), C-RNTI (Common - RNTI), Temporary C-RNTI (TC-RNTI), RA-RNTI (Random Access - RNTI), CC-RNTI (Common Control - RNTI), and INT-RNTI (Interruption - RNTI). SI-RNTI is used at least for scheduling a PDSCH containing system information and transmitted. P-RNTI is used at least for scheduling a PDSCH containing information such as paging information and / or a system information change notification. C-RNTI is used at least for scheduling user data for an RRC-connected terminal device 1. Temporary C-RNTI is used at least for scheduling a random access message 4. Temporary C-RNTI is used at least for scheduling a PDSCH containing data mapped to a CCCH in a logical channel. RA-RNTI is used at least for scheduling a random access message 2. The CC-RNTI is used at least for transmitting and receiving control information for unlicensed access, and the INT-RNTI is used at least for indicating pre-emption in the downlink.

[0126] Note that the PDCCH and / or DCI included in the CSS does not necessarily have to include a CIF (Carrier Indicator Field) indicating which serving cell (or which component carrier) the PDCCH / DCI is scheduling the PDSCH or PUSCH for.

[0127] In addition, when carrier aggregation (CA), which aggregates multiple serving cells and / or multiple component carriers to communicate (transmit and / or receive), is configured for the terminal device 1, the PDCCH and / or DCI included in the USS for a specific serving cell (specific component carrier) may include a CIF indicating which serving cell and / or which component carrier the PDCCH / DCI is scheduling the PDSCH or PUSCH for.

[0128] In addition, when communication is performed using one serving cell and / or one component carrier for terminal device 1, the PDCCH and / or DCI included in the USS may not include a CIF indicating which serving cell and / or which component carrier the PDCCH / DCI is scheduling the PDSCH or PUSCH for.

[0129] The common control resource set may include a CSS. The common control resource set may include both a CSS and a USS. The dedicated control resource set may include a USS. The dedicated control resource set may include a CSS.

[0130] The physical resources of the search area are composed of control channel components (CCEs). Each CCE is composed of a predetermined number of resource element groups (REGs). For example, a CCE may be composed of six REGs. A REG may be composed of one OFDM symbol of one PRB (Physical Resource Block). In other words, a REG may be composed of 12 resource elements (REs). A PRB is also simply called an RB (Resource Block).

[0131] That is, the terminal device 1 can detect the PDCCH and / or DCI for the terminal device 1 by blindly detecting PDCCH candidates included in a search space within a control resource set.

[0132] The number of blind detections for one control resource set in one serving cell and / or one component carrier may be determined based on the type of search space for the PDCCH included in the control resource set, the type of aggregation level, and the number of PDCCH candidates. As the search space set, the number of PDCCH candidates for each aggregation level may be configured for the terminal device 1. Here, the type of search space may include at least one of CSS and / or USS and / or UGSS (UE Group SS) and / or GCSS (Group CSS). The type of aggregation level indicates the maximum aggregation level supported for the CCEs that make up the search space, and may be specified / set from at least one of {1, 2, 4, 8, ..., X} (X is a predetermined value). The number of PDCCH candidates may indicate the number of PDCCH candidates for a certain aggregation level. In other words, the number of PDCCH candidates may be specified / set for each of multiple aggregation levels. Note that the UGSS may be a search space commonly assigned to one or more terminal devices 1. The GCSS may be a search space onto which DCI including parameters related to CSS is mapped for one or more terminal devices 1. Note that the aggregation level indicates an aggregation level for a predetermined number of CCEs and is related to the total number of CCEs that make up one PDCCH and / or search space.

[0133] The magnitude of the aggregation level may be associated with the coverage corresponding to the PDCCH and / or the search area, or the size of the DCI included in the PDCCH and / or the search area (DCI format size, payload size). The type of DCI format to be monitored may be configured for each search area.

[0134] Note that, when a start position (start symbol) of a PDCCH symbol is set for one control resource set, and when more than one PDCCH in the control resource set can be detected within a predetermined period, the type of search space for the PDCCH included in the control resource set, the type of aggregation level, and the number of PDCCH candidates may be set for the time domain corresponding to each start symbol. When more than one start position (start symbol) of the PDCCH symbol is set for one control resource set, that is, when there are multiple timings for blind detection (monitoring) of the PDCCH within a predetermined period, the type of search space for the PDCCH included in the control resource set, the type of aggregation level, and the number of PDCCH candidates may be set for the time domain corresponding to each start symbol. The type of search space, the type of aggregation level, and the number of PDCCH candidates for the PDCCH included in the control resource set may be set for each control resource set, or may be provided / set via DCI and / or higher layer signaling (RRC signaling), or may be specified / set in advance by a specification. Note that the number of PDCCH candidates may be the number of PDCCH candidates within a predetermined period. The predetermined period may be 1 millisecond, 1 microsecond, 1 slot, or 1 OFDM symbol.

[0135] As a method of indicating the number of PDCCH candidates, a configuration may be adopted in which the number to be reduced from a predetermined number of PDCCH candidates is specified / set for each aggregation level.

[0136] The terminal device 1 may transmit / notify the base station device 3 of capability information related to blind detection. The terminal device 1 may transmit / notify the base station device 3 of the number of PDCCH candidates that can be processed in one subframe as capability information related to the PDCCH. The terminal device 1 may transmit / notify the base station device 3 of capability information related to blind detection when more than a predetermined number of control resource sets can be configured for one or more serving cells / component carriers. The terminal device 1 may transmit / notify the base station device 3 of the number of PDCCH candidates that can be processed in one slot as capability information related to the PDCCH. The terminal device 1 may transmit / notify the base station device 3 of the number of PDCCH candidates that can be processed in multiple slots (e.g., four slots, eight slots) as capability information related to the PDCCH. The terminal device 1 may transmit / notify the base station device 3 of the number of PDCCH candidates that can be processed in one slot when multi-slot scheduling and single-slot scheduling are used together as capability information related to the PDCCH. The terminal device 1 may transmit / notify the base station device 3 of the number (upper limit) of PDCCH candidates that can be processed in one slot when only single slot scheduling is applied without multi-slot scheduling, and the number (upper limit) of PDCCH candidates that can be processed in one slot when multi-slot scheduling and single slot scheduling are used in combination, as capability information related to the PDCCH, using separate information (information elements). The terminal device 1 may transmit / notify the base station device 3 of the number (upper limit) of PDCCH candidates that can be processed in one slot with respect to the DCI format for single slot scheduling (first upper limit) as capability information related to the PDCCH. The terminal device 1 may transmit / notify the base station device 3 of the number (upper limit) of PDCCH candidates that can be processed in one slot with respect to the DCI format for single slot scheduling when multi-slot scheduling and single slot scheduling are used in combination, as capability information related to the PDCCH.The terminal device 1 may transmit / notify the base station device 3 of the number (upper limit) (first upper limit) of PDCCH candidates that can be processed in one slot for the DCI format for single slot scheduling and the DCI format for multi-slot scheduling when multi-slot scheduling and single slot scheduling are used together, as capability information related to the PDCCH. The terminal device 1 may transmit / notify the base station device 3 of capability information related to blind detection of the PDCCH for each subcarrier interval.

[0137] If the terminal device 1 can configure more than a predetermined number of control resource sets for a predetermined period of one or more serving cells / component carriers, the terminal device 1 may transmit / notify the base station device 3 of capability information related to blind detection.

[0138] The capability information related to blind detection may include information indicating the maximum number of blind detections in a predetermined period. The capability information related to blind detection may also include information indicating that PDCCH candidates can be reduced. The capability information related to blind detection may also include information indicating the maximum number of control resource sets on which blind detection is possible in a predetermined period. The maximum number of control resource sets and the maximum number of serving cells and / or component carriers on which PDCCH monitoring is possible may be set as individual parameters or as a common parameter. The capability information related to blind detection may also include information indicating the maximum number of control resource sets on which blind detection can be performed simultaneously in a predetermined period.

[0139] If the terminal device 1 does not support the capability to detect (blind detection) more than a predetermined number of control resource sets in a predetermined period, the terminal device 1 may not transmit / notify capability information related to the blind detection. If the base station device 3 does not receive the capability information related to the blind detection, the base station device 3 may configure the control resource sets so that the number does not exceed the predetermined number for blind detection, and transmit the PDCCH.

[0140] The configuration related to the control resource set includes a parameter indicating an index (ControlResourceSetId) for identifying the control resource set. The configuration related to the control resource set may also include a parameter indicating a frequency resource region of the control resource set (the number of resource blocks constituting the control resource set). The configuration related to the control resource set may also include a parameter indicating a type of mapping from CCE to REG. The configuration related to the control resource set may also include a REG bundle size. RRC signaling may be used to transmit and receive a message indicating the configuration related to the control resource set. SIB may be used to transmit and receive a message indicating the configuration related to the control resource set. MIB may be used to transmit and receive a message indicating the configuration related to the control resource set.

[0141] The search area configuration includes a parameter indicating an index (search area index) that identifies the search area. The search area configuration includes a parameter indicating an index of a control resource set in which the search area is arranged. The search area configuration may include parameters indicating a periodicity of the slot in which the search area is arranged and an offset (a relative slot position in which the search area is arranged). The search area configuration may include a parameter indicating the number of slots in which the search area is consecutively arranged. The search area configuration may include a parameter indicating an OFDM symbol in a slot in which PDCCH candidate monitoring is performed. The search area configuration may include a parameter indicating the number of PDCCH candidates to be monitored for each CCE aggregation level. The search area configuration may include a parameter indicating a DCI format in which monitoring is performed. The search area configuration may include a parameter indicating a search area type (CSS or USS). RRC signaling may be used to transmit and receive a message indicating the search area configuration. A SIB may be used to transmit and receive a message indicating the search area configuration. A MIB may be used to transmit and receive a message indicating the search area configuration.

[0142] As a parameter indicating the DCI format for monitoring, a downlink grant including scheduling information for multiple PDSCHs may be included in the search space configuration. As a parameter indicating the DCI format for monitoring, a downlink grant including scheduling information for one PDSCH for one slot (DCI format for single-slot scheduling) may be included in the search space configuration. As a parameter indicating the DCI format for monitoring, a downlink grant including scheduling information for multiple PDSCHs for multiple slots (DCI format for multi-slot scheduling) may be included in the search space configuration. As a parameter indicating the DCI format for monitoring, a downlink grant including scheduling information for PDSCHs for multiple cells may be included in the search space configuration. As a parameter indicating the DCI format for monitoring, a downlink grant including scheduling information for multiple PDSCHs for multiple cells may be included in the search space configuration. Here, the multiple cells may be the cell in which the search space is set and the cell to which cross-carrier scheduling is applied from the cell in which the search space is set.

[0143] Base station device 3 sets a search area for terminal device 1. Base station device 3 transmits setting information regarding the search area to terminal device 1. Terminal device 1 receives setting information regarding the search area from base station device 3. Terminal device 1 sets a search area based on the information received from base station device 3.

[0144] The PDSCH is used at least to transmit / receive transport blocks. The PDSCH may be used at least to transmit / receive a random access message 2 (random access response). The PDSCH may be used at least to transmit / receive system information including parameters used for initial access.

[0145] In Figure 1, the following downlink physical signals are used in downlink wireless communication: The downlink physical signals may not be used to transmit information output from higher layers, but are used by the physical layer. ·Synchronization signal (SS) ·DL DMRS(DownLink DeModulation Reference Signal) ·CSI-RS(Channel State Information-Reference Signal) ·DL PTRS(DownLink Phase Tracking Reference Signal)

[0146] The synchronization signal is used for synchronization in the frequency domain and / or the time domain of the downlink by the terminal device 1. The synchronization signal includes a PSS (Primary Synchronization Signal) and an SSS (Secondary Synchronization Signal).

[0147] An SS block (SS / PBCH block) is configured to include at least a part or all of a PSS, an SSS, and a PBCH.

[0148] The DL DMRS is related to the transmission of the PBCH, PDCCH, and / or PDSCH. The DL DMRS is multiplexed onto the PBCH, PDCCH, and / or PDSCH. The terminal device 1 may use the DL DMRS corresponding to the PBCH, PDCCH, or PDSCH to perform propagation path correction for the PBCH, PDCCH, or PDSCH. The terminal device 1 may determine that the base station device 3 is transmitting a signal based on detection of the DL DMRS.

[0149] The CSI-RS may be a signal that is at least used to calculate channel state information. The CSI-RS pattern assumed by the terminal device 1 may be given by at least higher layer parameters.

[0150] The PTRS may be a signal that is used at least for phase noise compensation. The pattern of the PTRS assumed by the terminal device 1 may be based at least on higher layer parameters and / or DCI.

[0151] A DL PTRS may be associated with a DL DMRS group that includes at least the antenna ports used for one or more DL DMRSs.

[0152] Note that a downlink physical signal not described above may also be used.

[0153] The downlink physical channel and the downlink physical signal are also referred to as downlink signals. The uplink physical channel and the uplink physical signal are also referred to as uplink signals. The downlink signal and the uplink signal are also collectively referred to as physical signals. The downlink signal and the uplink signal are also collectively referred to as signals. The downlink physical channel and the uplink physical channel are collectively referred to as physical channels. The downlink physical signal and the uplink physical signal are collectively referred to as physical signals.

[0154] The BCH (Broadcast CHannel), UL-SCH (Uplink-Shared CHannel), and DL-SCH (Downlink-Shared CHannel) are transport channels. Channels used in the Medium Access Control (MAC) layer are called transport channels. The unit of transport channel used in the MAC layer is also called a transport block (TB) or MAC PDU. In the MAC layer, HARQ (Hybrid Automatic Repeat reQuest) control is performed for each transport block. A transport block is a unit of data that the MAC layer delivers to the physical layer. In the physical layer, a transport block is mapped to a codeword, and modulation processing is performed for each codeword.

[0155] The base station device 3 and the terminal device 1 exchange (transmit and receive) higher layer signals in a higher layer. For example, the base station device 3 and the terminal device 1 may transmit and receive RRC signaling (RRC message: Radio Resource Control message; RRC information: Radio Resource Control information) in a Radio Resource Control (RRC) layer. The base station device 3 and the terminal device 1 may also transmit and receive MAC CE (Control Element) in a MAC layer. Here, the RRC signaling and / or MAC CE are also referred to as higher layer signaling.

[0156] The PUSCH and the PDSCH may be used at least for transmitting RRC signaling and / or MAC CE. Here, the RRC signaling transmitted by the base station device 3 on the PDSCH may be signaling common to multiple terminal devices 1 in the serving cell. Signaling common to multiple terminal devices 1 in the serving cell is also referred to as common RRC signaling. The RRC signaling transmitted by the base station device 3 on the PDSCH may be signaling dedicated to a certain terminal device 1 (also referred to as dedicated signaling or UE specific signaling). Signaling dedicated to a terminal device 1 is also referred to as dedicated RRC signaling. Upper layer parameters specific to a serving cell may be transmitted / received using signaling common to multiple terminal devices 1 in the serving cell or signaling dedicated to a certain terminal device 1. Upper layer parameters specific to a UE may be transmitted / received using signaling dedicated to a certain terminal device 1.

[0157] The BCCH (Broadcast Control CHannel), CCCH (Common Control CHannel), and DCCH (Dedicated Control CHannel) are logical channels. For example, the BCCH is an upper layer channel used for transmitting / receiving an MIB. The CCCH (Common Control CHannel) is an upper layer channel used for transmitting / receiving information common to a plurality of terminal devices 1. Here, the CCCH may be used, for example, for terminal devices 1 that are not RRC connected. The DCCH (Dedicated Control CHannel) is an upper layer channel that is used at least for transmitting / receiving control information dedicated to the terminal device 1. Here, the DCCH may be used, for example, for terminal devices 1 that are RRC connected.

[0158] The BCCH in the logical channel may be mapped to the BCH, DL-SCH, or UL-SCH in the transport channel. The CCCH in the logical channel may be mapped to the DL-SCH or UL-SCH in the transport channel. The DCCH in the logical channel may be mapped to the DL-SCH or UL-SCH in the transport channel.

[0159] The UL-SCH in the transport channel may be mapped to the PUSCH in the physical channel, the DL-SCH in the transport channel may be mapped to the PDSCH in the physical channel, and the BCH in the transport channel may be mapped to the PBCH in the physical channel.

[0160] An example of the configuration of the terminal device 1 according to one aspect of this embodiment will be described below.

[0161] 5 is a schematic block diagram showing the configuration of a terminal device 1 according to one aspect of the present embodiment. As shown in the figure, the terminal device 1 includes a radio transmission / reception unit 10 and an upper layer processing unit 14. The radio transmission / reception unit 10 includes at least an antenna unit 11, an RF (Radio Frequency) unit 12, and part or all of a baseband unit 13. The upper layer processing unit 14 includes at least a medium access control layer processing unit 15 and part or all of a radio resource control layer processing unit 16. The radio transmission / reception unit 10 is also referred to as a transmitter, a receiver, or a physical layer processing unit.

[0162] The physical layer processing unit includes a decoding unit. A receiving unit (also referred to as a receiving processing unit) of the terminal device 1 receives a PDCCH. A decoding unit of the terminal device 1 decodes the received PDCCH. More specifically, the decoding unit of the terminal device 1 performs blind decoding processing on received signals of resources corresponding to PDCCH candidates of the USS. The decoding unit of the terminal device 1 performs blind decoding processing on received signals of resources corresponding to PDCCH candidates of the CSS. A receiving processing unit of the terminal device 1 monitors PDCCH candidates within a control resource set. A receiving processing unit of the terminal device 1 monitors PDCCH candidates within a control resource set. The decoding unit of the terminal device 1 performs different blind decoding processing for each DCI format of a different size.

[0163] A transmitter (also referred to as a transmission processing unit) of the terminal device 1 transmits a HARQ-ACK. The transmission processing unit of the terminal device 1 transmits a HARQ-ACK for the PDSCH. The transmission processing unit of the terminal device 1 transmits a HARQ-ACK in an uplink frequency band (cell, component carrier, carrier) managed by the base station device 3. The transmission processing unit of the terminal device 1 transmits a HARQ-ACK for the PDSCH in a downlink frequency band (cell, component carrier, carrier) managed by the base station device 3. The transmission processing unit of the terminal device 1 transmits a HARQ-ACK for the PDSCH in a downlink frequency band (cell, component carrier, carrier) managed by the base station device 3 in an uplink frequency band (cell, component carrier, carrier) managed by the base station device 3.

[0164] The upper layer processing unit 14 outputs uplink data (transport blocks) generated by user operations or the like to the radio transceiver unit 10. The upper layer processing unit 14 performs processing on the MAC layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, and RRC layer.

[0165] The medium access control layer processing unit 15 included in the upper layer processing unit 14 performs processing of the MAC layer.

[0166] The radio resource control layer processing unit 16 included in the upper layer processing unit 14 performs processing of the RRC layer. The radio resource control layer processing unit 16 manages various setting information / parameters of its own device. The radio resource control layer processing unit 16 sets various setting information / parameters based on upper layer signals received from the base station device 3. That is, the radio resource control layer processing unit 16 sets various setting information / parameters based on information indicating the various setting information / parameters received from the base station device 3. The setting information may include information related to processing or setting of physical channels and physical signals (i.e., the physical layer), MAC layer, PDCP layer, RLC layer, and RRC layer. The parameters may be upper layer parameters.

[0167] The radio resource control layer processing unit 16 sets a control resource set based on RRC signaling received from the base station device 3. The radio resource control layer processing unit 16 sets (configures) a search space within the control resource set. The radio resource control layer processing unit 16 sets (configures) PDCCH candidates to be monitored within the control resource set. The radio resource control layer processing unit 16 sets (configures) the number of PDCCH candidates to be monitored within the control resource set. The radio resource control processing unit 16 sets (configures) an aggregation level for the PDCCH candidates to be monitored within the control resource set.

[0168] The radio resource control layer processing unit 16 sets a DCI format to be monitored within a control resource set. The radio resource control layer processing unit 16 may set a DCI format to be monitored within a search space. The radio resource control layer processing unit 16 sets a DCI format to be monitored within a control resource set based on RRC signaling indicated from the base station device 3. The radio resource control layer processing unit 16 may set a DCI format to be monitored within a search space based on RRC signaling indicated from the base station device 3. The radio resource control layer processing unit 16 sets one or more DCI formats to be monitored in the reception processing unit.

[0169] The wireless transceiver 10 performs physical layer processing such as modulation, demodulation, encoding, and decoding. The wireless transceiver 10 separates, demodulates, and decodes the received physical signal, and outputs the decoded information to the upper layer processing unit 14. The wireless transceiver 10 generates a physical signal by modulating and encoding the data and generating a baseband signal (converting it into a time-continuous signal), and transmits the physical signal to the base station device 3.

[0170] The RF unit 12 converts the signal received via the antenna unit 11 into a baseband signal by quadrature demodulation (down-converts) and removes unnecessary frequency components. The RF unit 12 outputs the processed analog signal to the baseband unit.

[0171] 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 a cyclic prefix (CP) from the converted digital signal, and performs a fast Fourier transform (FFT) on the signal from which the CP has been removed to extract a signal in the frequency domain.

[0172] The baseband unit 13 performs an Inverse Fast Fourier Transform (IFFT) on the data to generate OFDM symbols, adds CPs to the generated OFDM symbols, generates baseband digital signals, and converts the baseband digital signals into analog signals. The baseband unit 13 outputs the converted analog signals to the RF unit 12.

[0173] The RF unit 12 uses a low-pass filter to remove unnecessary frequency components from the analog signal input from the baseband unit 13, up-converts the analog signal to a carrier frequency, and transmits it via the antenna unit 11. The RF unit 12 also amplifies power. The RF unit 12 may also have a function to control transmission power. The RF unit 12 is also referred to as a transmission power control unit.

[0174] The terminal device 1 receives a PDCCH. The terminal device 1 receives a PDSCH. The radio resource control layer processing unit 16 sets a control resource set. The radio resource control layer processing unit 16 sets a search space. The radio resource control layer processing unit 16 sets a control resource set based on RRC signaling. The radio resource control layer processing unit 16 sets the search space based on RRC signaling. The receiving unit of the terminal device 1 monitors multiple PDCCH candidates within the search space of the set control resource set. The receiving unit of the terminal device 1 monitors multiple PDCCH candidates within the search space of the set control resource set in a certain slot. The receiving unit of the terminal device 1 monitors the PDCCH candidates assuming a DCI format. The decoding unit of the terminal device 1 decodes the monitored PDCCH candidates. The decoding unit of the terminal device 1 decodes the PDCCH candidates to acquire a downlink DCI format and recognizes the scheduling information of the PDSCH. The decoding unit of the terminal device 1 decodes the received PDSCH.

[0175] The receiving unit of the terminal device 1 monitors PDCCH candidates in a search area of ​​a control resource set in a certain slot based on the number set based on RRC signaling. The receiving unit of the terminal device 1 monitors PDCCH candidates consisting of one or more OFDM symbols set based on RRC signaling in a search area of ​​a control resource set in a certain slot. Note that the receiving unit of the terminal device 1 may set three or more search areas in a certain slot, each search area being a different OFDM symbol, and monitor PDCCH candidates in a distributed manner within the slot. The receiving unit of the terminal device 1 monitors PDCCH candidates assuming a DCI format set based on RRC signaling.

[0176] An example of the configuration of the base station device 3 according to one aspect of this embodiment will be described below.

[0177] 6 is a schematic block diagram showing the configuration of a base station device 3 according to one aspect of the present embodiment. As shown in the figure, the base station device 3 includes a radio transmission / reception unit 30 and an upper layer processing unit 34. The radio transmission / reception unit 30 includes an antenna unit 31, an RF unit 32, and a baseband unit 33. The upper layer processing unit 34 includes a medium access control layer processing unit 35 and a radio resource control layer processing unit 36. The radio transmission / reception unit 30 is also referred to as a transmitter, a receiver, or a physical layer processing unit.

[0178] The upper layer processing unit 34 performs processing for the MAC layer, the PDCP layer, the RLC layer, and the RRC layer.

[0179] The medium access control layer processing unit 35 included in the upper layer processing unit 34 performs MAC layer processing.

[0180] The radio resource control layer processing unit 36 ​​included in the upper layer processing unit 34 performs processing of the RRC layer. The radio resource control layer processing unit 36 ​​generates downlink data (transport blocks) to be allocated to the PDSCH, system information, RRC messages, MAC CE, etc., or acquires them from an upper node and outputs them to the radio transceiver unit 30. The radio resource control layer processing unit 36 ​​also manages various setting information / parameters for each terminal device 1. The radio resource control layer processing unit 36 ​​may set various setting information / parameters for each terminal device 1 via upper layer signals. That is, the radio resource control layer processing unit 36 ​​transmits / reports information indicating various setting information / parameters. The setting information may include information related to processing or setting of a physical channel or physical signal (i.e., the physical layer), MAC layer, PDCP layer, RLC layer, and RRC layer. The parameters may be upper layer parameters.

[0181] The radio resource control layer processing unit 36 ​​sets a control resource set for the terminal device 1. Multiple PDCCH candidates are configured (set) within the set control resource set. The radio resource control layer processing unit 36 ​​sets a search space for the terminal device 1. The radio resource control layer processing unit 36 ​​sets a DCI format to be monitored in the search space for the terminal device 1. The radio resource control layer processing unit 36 ​​sets resources for transmitting HARQ-ACK for the terminal device 1.

[0182] The radio resource control layer processing unit 36 ​​sets a DCI format to be applied to the terminal device 1 within the control resource set. The radio resource control layer processing unit 36 ​​generates RRC signaling indicating the DCI format to be applied to the terminal device 1. The radio resource control layer processing unit 36 ​​sets one or more DCI formats to be applied in the transmission processing unit.

[0183] The functions of the radio transceiver 30 are similar to those of the radio transceiver 10, and therefore description thereof will be omitted where appropriate. The radio transceiver 30 identifies an SS (Search space) configured in the terminal device 1. The radio transceiver 30 identifies a search space in a control resource set configured in the terminal device 1. The radio transceiver 30 identifies PDCCH candidates monitored in the terminal device 1 to identify the search space. The radio transceiver 30 identifies which control channel elements each PDCCH candidate monitored in the terminal device 1 is configured from (identifies the numbers of the control channel elements in which the PDCCH candidate is configured). The radio transceiver 30 includes an SS identifying unit, and the SS identifying unit identifies an SS configured in the terminal device 1. The SS identifying unit identifies one or more PDCCH candidates in a control resource set configured as a Search space of the terminal device. The SS identifying unit identifies PDCCH candidates (the number of PDCCH candidates, the numbers of the PDCCH candidates) configured in the search space of the control resource set of the terminal device 1.

[0184] The SS ascertaining unit ascertains the configuration of the search space within the control resource set (the number of PDCCH candidates, the OFDM symbols of the PDCCH candidates, and the aggregation level of the PDCCH candidates). The transmitting unit (transmission processing unit) of the radio transceiver unit 30 transmits the PDCCH to the terminal device 1 using the PDCCH candidates within the search space of the control resource set.

[0185] The receiving unit (also referred to as the receiving processing unit) of the base station device 3 receives the HARQ-ACK. The receiving processing unit of the base station device 3 receives the HARQ-ACK for the PDSCH. The receiving processing unit of the base station device 3 receives the HARQ-ACK in the uplink frequency band (cell, component carrier, carrier). The receiving processing unit of the base station device 3 receives the HARQ-ACK for the PDSCH in the downlink frequency band (cell, component carrier, carrier) in the uplink frequency band (cell, component carrier, carrier).

[0186] Each of the units designated by reference numerals 10 to 16 in the terminal device 1 may be configured as a circuit. Each of the units designated by reference numerals 30 to 36 in the base station device 3 may be configured as a circuit.

[0187] The terminal device 1 transmits uplink control information (UCI) to the base station device 3. The terminal device 1 may multiplex the UCI onto a PUCCH and transmit the same. The terminal device 1 may multiplex the UCI onto a PUSCH and transmit the same. The UCI may include at least one of downlink channel state information (CSI), a scheduling request (SR) indicating a request for PUSCH resources, and a hybrid automatic repeat request ACKnowledgement (HARQ-ACK) for downlink data (Transport block, Medium Access Control Protocol Data Unit: MAC PDU, Downlink-Shared Channel: DL-SCH, Physical Downlink Shared Channel: PDSCH).

[0188] HARQ-ACK may also be referred to as 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.

[0189] If downlink data is successfully decoded, an ACK for the downlink data is generated. If downlink data is not successfully decoded, a NACK for the downlink data is generated. The HARQ-ACK may include at least a HARQ-ACK bit corresponding to at least one transport block. The HARQ-ACK bit may indicate an ACK (ACKnowledgement) or a NACK (Negative-ACKnowledgement) corresponding to one or multiple transport blocks. The HARQ-ACK may include at least a HARQ-ACK codebook including one or multiple HARQ-ACK bits. The HARQ-ACK bit corresponding to one or multiple transport blocks may correspond to a PDSCH including the one or multiple transport blocks.

[0190] HARQ control for one transport block may be referred to as an HARQ process. One HARQ process identifier may be assigned to each HARQ process. The DCI format includes a field indicating the HARQ process identifier.

[0191] An NDI (New Data Indicator) is indicated in the DCI format for each HARQ process. For example, an NDI field is included in a DCI format (DL assignment) including scheduling information for PDSCH. The NDI field is 1 bit. The terminal device 1 stores (stores) an NDI value for each HARQ process. The base station device 3 stores (stores) an NDI value for each HARQ process for each terminal device 1. The terminal device 1 updates the stored NDI value using the NDI field of the detected DCI format. The base station device 3 sets the updated NDI value or the NDI value that is not updated in the NDI field of the DCI format and transmits it to the terminal device 1. The terminal device 1 updates the stored NDI value using the NDI field of the detected DCI format for the HARQ process corresponding to the value of the HARQ process identifier field of the detected DCI format.

[0192] The terminal device 1 determines whether a 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 the NDI field of the detected DCI format with the value of the NDI previously received for the transport block of a certain HARQ process, and if the value of the NDI field is toggled, determines that the received transport block is a new transmission. When transmitting a transport block for new transmission in a certain HARQ process, the base station device 3 toggles the value of the NDI 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 value of the NDI stored for the HARQ process and transmits an untoggled NDI to the terminal device 1. The terminal device 1 compares the value of the NDI field of the detected DCI format with the value of the NDI previously received for the transport block of a certain HARQ process, and if the value is not toggled (they are the same), determines that the received transport block is a retransmission. Note that toggling here means switching to a different value.

[0193] The terminal device 1 may report HARQ-ACK information to the base station device 3 using a HARQ-ACK codebook in a slot indicated by the value of the HARQ indication field included in DCI format 1_0 corresponding to PDSCH reception or DCI format 1_1.

[0194] 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 a set of slot numbers given by the higher layer parameter dl-DataToUL-ACK. The number of slots indicated based at least on the value of the HARQ indication field may also be referred to as HARQ-ACK timing or K1. For example, a HARQ-ACK indicating the decoding status of PDSCH (downlink data) transmitted in slot n may be reported (transmitted) in slot n+K1.

[0195] The dl-DataToUL-ACK indicates a list of HARQ-ACK timings for the PDSCH. The timings refer to 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. For example, the dl-DataToUL-ACK is a list of 1, 2, 3, 4, 5, 6, 7, or 8 timings. If the dl-DataToUL-ACK is a list of 1 timing, the HARQ indication field is 0 bits. If the dl-DataToUL-ACK is a list of 2 timings, the HARQ indication field is 1 bit. If the 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 timings with values ​​ranging from 0 to 31. For example, dl-DataToUL-ACK consists of a list of timings with values ​​ranging from 0 to 63.

[0196] The size of a dl-DataToUL-ACK is defined as the number of elements it contains. 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 one of the values ​​1, 2, 3, 4, 5, 6, 7, or 8. The index of dl-DataToUL-ACK may be given, indicated, or indicated by the value indicated by the HARQ indication field.

[0197] The terminal device 1 may set the size of the HARQ-ACK codebook according to the size of the dl-DataToUL-ACK. For example, if the dl-DataToUL-ACK consists of eight elements, the size of the HARQ-ACK codebook is 8. For example, if the dl-DataToUL-ACK consists of two elements, the size of the HARQ-ACK codebook is 2. Each piece of HARQ-ACK information constituting the HARQ-ACK codebook is HARQ-ACK information for PDSCH reception at each slot timing of the dl-DataToUL-ACK. This type of HARQ-ACK codebook is also called a semi-static HARQ-ACK codebook.

[0198] An example of the setting of the HARQ indication field will be described below. For example, the dl-DataToUL-ACK consists of a list of eight timings: 0, 7, 15, 23, 31, 39, 47, and 55, and the HARQ indication field consists of three bits. A HARQ indication field of "000" corresponds to the first timing, 0, in the list of dl-DataToUL-ACK. That is, a HARQ indication field of "000" corresponds to the value 0 indicated by index 1 in the dl-DataToUL-ACK. A HARQ indication field of "001" corresponds to the second timing, 7, in the list of dl-DataToUL-ACK. A HARQ indication field of "010" corresponds to the third timing, 15, in the list of dl-DataToUL-ACK. A HARQ indication field of "011" corresponds to the fourth timing, 23, in the list of dl-DataToUL-ACK. The HARQ indication field value of "100" corresponds to the fifth value, 31, in the list of dl-DataToUL-ACKs as the corresponding timing. The HARQ indication field value of "101" corresponds to the sixth value, 39, in the list of dl-DataToUL-ACKs as the corresponding timing. The HARQ indication field value of "110" corresponds to the seventh value, 47, in the list of dl-DataToUL-ACKs as the corresponding timing. The HARQ indication field value of "111" corresponds to the eighth value, 55, in the list of dl-DataToUL-ACKs as the corresponding timing. If the received HARQ indication field indicates "000", the terminal device 1 transmits the corresponding HARQ-ACK in the 0th slot from the slots of the received PDSCH. If the received HARQ indication field indicates "001", the terminal device 1 transmits the corresponding HARQ-ACK in the seventh slot from the slots of the received PDSCH. If the received HARQ indication field indicates "010", the terminal device 1 transmits the corresponding HARQ-ACK in the 15th slot from the slots of the received PDSCH. If the received HARQ indication field indicates "011", the terminal device 1 transmits the corresponding HARQ-ACK in the 23rd slot from the slots of the received PDSCH.If the received HARQ indication field indicates "100", the terminal device 1 transmits the corresponding HARQ-ACK in the 31st slot from the slots of the received PDSCH. If the received HARQ indication field indicates "101", the terminal device 1 transmits the corresponding HARQ-ACK in the 39th slot from the slots of the received PDSCH. If the received HARQ indication field indicates "110", the terminal device 1 transmits the corresponding HARQ-ACK in the 47th slot from the slots of the received PDSCH. If the received HARQ indication field indicates "111", the terminal device 1 transmits the corresponding HARQ-ACK in the 55th slot from the slots of the received PDSCH.

[0199] When the upper layer parameter pdsch-AggregationFactor is given to the terminal device 1, N PDSCH repeat may be the value of pdsch-AggregationFactor. If the upper layer parameter pdsch-AggregationFactor is not provided to the terminal device 1, N PDSCH repeat may be 1. Terminal device 1 is in slot nN PDSCH repeat HARQ-ACK information for PDSCH receptions from slot n+1 to slot n may be reported using a PUCCH transmission and / or a PUSCH transmission in slot n+k, where k may be the number of slots indicated by the HARQ indication field included in the DCI format corresponding to the PDSCH reception. Alternatively, if the HARQ indication field is not included in the DCI format, k may be provided by the higher layer parameter dl-DataToUL-ACK.

[0200] When the terminal device 1 is configured to monitor a PDCCH including DCI format 1_0 and not to monitor a PDCCH including DCI format 1_1, the HARQ-ACK timing value K1 may be some or all of (1, 2, 3, 4, 5, 6, 7, 8). When the terminal device 1 is configured to monitor a PDCCH including DCI format 1_1, the HARQ-ACK timing value K1 may be provided by the higher layer parameter dl-DataToUL-ACK.

[0201] The terminal device 1 determines a set of multiple opportunities for one or more candidate PDSCH receptions, for transmitting corresponding HARQ-ACK information in the PUCCH of a certain slot. The terminal device 1 may determine multiple slots of slot timing K1 included in the dl-DataToUL-ACK as multiple opportunities for candidate PDSCH receptions. K1 may be a set of k. For example, when the dl-DataToUL-ACK is (1, 2, 3, 4, 5, 6, 7, 8), in the PUCCH of slot n, HARQ-ACK information for the PDSCH reception of slot n-1, the PDSCH reception of slot n-2, the PDSCH reception of slot n-3, the PDSCH reception of slot n-4, the PDSCH reception of slot n-5, the PDSCH reception of slot n-6, the PDSCH reception of slot n-7, and the PDSCH reception of slot n-8 is transmitted. If the terminal device 1 actually receives a PDSCH in a slot corresponding to the candidate PDSCH reception, it sets ACK or NACK as the HARQ-ACK information based on the transport block contained in that PDSCH, and if it does not receive a PDSCH in the slot corresponding to the candidate PDSCH reception, it sets NACK as the HARQ-ACK information.

[0202] The HARQ indication field included in the DCI format received on the PDCCH in slot n-1 indicates 1. The HARQ indication field included in the DCI format received on the PDCCH in slot n-2 indicates 2. The HARQ indication field included in the DCI format received on the PDCCH in slot n-3 indicates 3. The HARQ indication field included in the DCI format received on the PDCCH in slot n-4 indicates 4. The HARQ indication field included in the DCI format received on the PDCCH in slot n-5 indicates 5. The HARQ indication field included in the DCI format received on the PDCCH in slot n-6 indicates 6. The HARQ indication field included in the DCI format received on the PDCCH in slot n-7 indicates 7. The HARQ indication field included in the DCI format received on the PDCCH in slot n-8 indicates 8.

[0203] The terminal device 1 determines the slot in which to transmit HARQ-ACK information and a set of multiple candidate PDSCH reception slots corresponding to the HARQ-ACK information based on the slot in which the PDCCH was received and the value of the HARQ indication field included in the received DCI format. For example, if dl-DataToUL-ACK is (1, 2, 3, 4, 5, 6, 7, 8), the terminal device 1 receives the PDCCH in slot m, and the HARQ indication field included in the DCI format indicates 4. The terminal device 1 determines to transmit the HARQ-ACK information in slot (m+4). The terminal device 1 determines that the other HARQ-ACK information transmitted in slot (m+4) is HARQ-ACK information for PDSCH reception in slot (m+(1-4)), HARQ-ACK information for PDSCH reception in slot (m+(2-4)), HARQ-ACK information for PDSCH reception in slot (m+(3-4)), HARQ-ACK information for PDSCH reception in slot (m+(5-4)), HARQ-ACK information for PDSCH reception in slot (m+(6-4)), HARQ-ACK information for PDSCH reception in slot (m+(7-4)), and HARQ-ACK information for PDSCH reception in slot (m+(8-4)).

[0204] Although the above description has been given of a semi-static HARQ-ACK codebook as one type of HARQ-ACK codebook, a different type of HARQ-ACK codebook may also be used. A type of HARQ-ACK codebook called a dynamic HARQ-ACK codebook will now be described.

[0205] The HARQ-ACK codebook corresponding to a certain PDSCH group is determined based on one or more HARQ-ACK bits corresponding to one or more transport blocks included in one or more PDSCHs included in the certain PDSCH group. The HARQ-ACK codebook is determined based on at least a set of PDCCH monitoring occasions and some or all of the value of the Counter DAI field. The HARQ-ACK codebook may be determined further based on the value of the UL DAI field. The HARQ-ACK codebook may be determined further based on the value of the DAI field. The HARQ-ACK codebook may be determined further based on the value of the Total DAI field.

[0206] The HARQ-ACK codebook size of the Dynamic HARQ-ACK codebook is based on a field in the DCI format. The size of the HARQ-ACK codebook may be set based on the value of the Counter DAI field in the last received DCI format. The Counter DAI field indicates the cumulative number of PDSCHs or transport blocks scheduled until reception of the corresponding DCI format. The Counter DAI field may indicate the cumulative number of PDCCHs transmitted 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 the DCI format. The Total DAI field indicates the total number of PDSCHs or transport blocks scheduled until transmission of the HARQ-ACK codebook. The Total DAI field may indicate the total number of PDCCHs transmitted until transmission of the HARQ-ACK codebook.

[0207] The terminal device 1 may determine a set of PDCCH monitoring opportunities for HARQ-ACK information transmitted in a PUCCH arranged in a slot with index n (slot #n) based at least on the value of timing K1 and part or all of the value of slot offset K0. The set of PDCCH monitoring opportunities for HARQ-ACK information transmitted in a PUCCH arranged in a slot with index n is also referred to as a set of PDCCH monitoring opportunities for slot n (monitoring occasions for PDCCH for slot #n). 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 a time domain resource allocation field included in a downlink DCI format. The slot offset K0 is a value indicating the number of slots (slot difference) from a slot including the last OFDM symbol in which a PDCCH including a DCI format including a time domain resource allocation field indicating the slot offset K0 is arranged to the first OFDM symbol of a PDSCH scheduled by the DCI format.

[0208] When a DCI format detected in a monitoring opportunity of any search space set corresponding to a monitoring opportunity of a certain PDCCH triggers (includes triggering information) transmission of HARQ-ACK information in slot n, the terminal device 1 may determine the PDCCH monitoring opportunity as a PDCCH monitoring opportunity for slot n. Also, when a DCI format detected in a monitoring opportunity of a search space set corresponding to a monitoring opportunity of a certain PDCCH does not trigger (does not include triggering information) transmission of HARQ-ACK information in slot n, the terminal device 1 may not determine the PDCCH monitoring opportunity as a PDCCH monitoring opportunity for slot n. Also, when no DCI format is detected in a monitoring opportunity of a search space set corresponding to a monitoring opportunity of a certain PDCCH, the terminal device 1 may not determine the PDCCH monitoring opportunity as a PDCCH monitoring opportunity for slot n.

[0209] The PUCCH resource used for transmitting the HARQ-ACK information in slot n may be identified based at least on a PUCCH resource indication field included in a last DCI format among one or more DCI formats detected in a set of PDCCH monitoring opportunities for slot n, where each of the one or more DCI formats triggers transmission of the HARQ-ACK information in slot n. The last DCI format may be a DCI format corresponding to the last index (highest index) among the DCI formats detected in the set of PDCCH monitoring opportunities for slot n. The indices of the DCI formats in the set of PDCCH monitoring opportunities for slot n are given in ascending order with respect to the index of the serving cell in which the DCI format is detected, and then with respect to the index of the PDCCH monitoring opportunity in which the DCI format is detected. The indices of the PDCCH monitoring opportunities are given in ascending order on the time axis.

[0210] A Counter DAI indicates, for a PDCCH monitoring opportunity in a serving cell among M PDCCH monitoring opportunities, the cumulative number of PDCCH signals detected up to the PDCCH monitoring opportunity in the serving cell (or may be a value at least related to the cumulative number). The Counter DAI may also be referred to as a C-DAI. The C-DAI corresponding to a PDSCH may be indicated by a field included in a DCI format used for scheduling the PDSCH. The Total DAI may indicate the cumulative number of PDCCH signals detected up to PDCCH monitoring opportunity m among M PDCCH monitoring opportunities (or may be a value at least related to the cumulative number). The Total DAI may also be referred to as a T-DAI (Total Downlink Assignment Index).

[0211] Fig. 7 is a diagram showing an example of the number of PDCCH candidates configured for each slot. Here, configured PDCCH candidates refer to PDCCH candidates configured by parameters of RRC signaling. Base station apparatus 3 notifies terminal apparatus 1 of the number of PDCCH candidates in a search space for each slot using RRC signaling. Terminal apparatus 1 is notified of the number of PDCCH candidates in a search space for each slot by base station apparatus 3 using RRC signaling. It is assumed that multiple search space parameters (period, number of PDCCH candidates per aggregation level) are notified to terminal apparatus 1, and the total number of PDCCH candidates in one or more search spaces configured for each slot is shown in Fig. 7. For example, if a search region is configured with a period of every 8 slots starting from slot #2 and with five aggregation level 1 PDCCH candidates, and another search region is configured with a period of every 4 slots starting from slot #2 and with two aggregation level 2 PDCCH candidates, one aggregation level 4 PDCCH candidate, and two aggregation level 8 PDCCH candidates, the number of PDCCH candidates configured in slot #2 will be 10, which is the sum of the respective PDCCH candidates (5 + 2 + 1 + 2).

[0212] In the terminal device 1, multiple upper limit values ​​(a first upper limit value, a second upper limit value) are used. The upper limit values ​​are for the number of PDCCH candidates to be monitored, and are used to adjust (drop) PDCCH candidates configured in the terminal device 1. The multiple upper limit values ​​may be set based on the capabilities of the terminal device 1, and the terminal device 1 may notify the base station device 3 of information on the multiple upper limit values. The multiple upper limit values ​​may be set (configured) in the base station device 3, and a parameter indicating the multiple upper limit values ​​set using RRC signaling may be notified to the terminal device 1, and the terminal device 1 may set the multiple upper limit values ​​based on the RRC signaling. The first upper limit value is used in units of one slot. The second upper limit value is used in units of multiple slots. The first upper limit value is an upper limit value for the number of PDCCH candidates to be monitored in one slot. The second upper limit value is an upper limit value for PDCCH candidates to be monitored in multiple slots. The first upper limit value may be an upper limit value used for monitoring PDCCH candidates including a DCI format for single-slot scheduling (a first DCI format). The second upper limit may be an upper limit used for monitoring PDCCH candidates including a DCI format for multi-slot scheduling (second DCI format). The second upper limit may be an upper limit used for monitoring both PDCCH candidates including a DCI format for multi-slot scheduling and PDCCH candidates including a DCI format for single-slot scheduling.

[0213] As an example, a case where 8 is set as the first upper limit and 45 is set as the second upper limit will be described. Also, a case where the second upper limit is used in units of 8 slots will be described. A DCI format for multi-slot scheduling is configured for the search space configured for slot #0. A DCI format for single-slot scheduling is configured for the search space of slot #2, slot #5, and slot #6.

[0214] First, the terminal device 1 determines whether the number of PDCCH candidates configured for each slot exceeds a first upper limit. Here, the terminal device 1 determines whether the number of PDCCH candidates that may include a DCI format for single-slot scheduling exceeds a first upper limit. Since there are 10 PDCCH candidates configured for slot #2, which exceeds the first upper limit of 8, the terminal device 1 drops the PDCCH candidates configured for slot #2 and adjusts the number of monitored PDCCH candidates to be 8 or less (smaller). Since there are 5 PDCCH candidates configured for slot #5, which does not exceed the first upper limit of 8, the terminal device 1 does not adjust (does not drop, reduce, or decrease) the configured PDCCH candidates. Since there are 5 PDCCH candidates configured for slot #6, which does not exceed the first upper limit of 8, the terminal device 1 does not adjust (does not drop, reduce, or decrease) the configured PDCCH candidates.

[0215] Next, the terminal device 1 determines whether the PDCCH candidates configured for eight slots exceed a second upper limit. Here, for slots in which the configured PDCCH candidates exceed the first upper limit, the adjusted PDCCH candidates are used. There are 30 PDCCH candidates configured in slot #0 in which the DCI format for multi-slot scheduling is configured, 8 PDCCH candidates adjusted based on the first upper limit in slot #2 in which the DCI format for single-slot scheduling is configured, 5 PDCCH candidates configured in slot #5 in which the DCI format for single-slot scheduling is configured, and 5 PDCCH candidates configured in slot #6 in which the DCI format for single-slot scheduling is configured. Since the total number of PDCCH candidates is 48, which exceeds the second upper limit of 45, the terminal device 1 drops (at least (48-45)=3) PDCCH candidates and adjusts the number of monitored PDCCH candidates so that they are equal to or less than the second upper limit. The terminal device 1 may preferentially drop PDCCH candidates in a search area with the largest or smallest search area number within eight slots. The terminal device 1 may preferentially drop PDCCH candidates in a search area in which a DCI format for multi-slot scheduling is configured. The terminal device 1 may preferentially drop PDCCH candidates in a search area of ​​the first or last slot.

[0216] For example, the terminal device 1 drops three PDCCH candidates from among the PDCCH candidates configured for slot #0, and sets the number of PDCCH candidates monitored in slot #0 to 27. For example, the terminal device 1 drops three PDCCH candidates from among the PDCCH candidates configured for slot #6, and sets the number of PDCCH candidates monitored in slot #6 to 2. For example, in slot #6, if five PDCCH candidates are configured in a search space of one configuration, the terminal device 1 may drop all five PDCCH candidates configured for slot #6. That is, the terminal device 1 may drop PDCCH candidates in search space configuration units within a slot. When search spaces of multiple configurations are configured within a slot, the terminal device 1 may preferentially monitor PDCCH candidates in search spaces of configurations with smaller search space numbers, and preferentially drop PDCCH candidates in search spaces of configurations with larger search space numbers.

[0217] In the above, as an example, the first upper limit value is described as 8, but may be a different value. In the above, as an example, the second upper limit value is described as 45, but may be a different value. In the above, as an example, the number of slots for which adjustment of PDCCH candidates monitored using the second upper limit value is performed is described as 8, but may be a different value.

[0218] The reception processing unit of the terminal device 1 adjusts (drops, reduces, or decreases) the PDCCH candidates configured for each slot so that the number of PDCCH candidates monitored in each slot does not exceed a first upper limit. The reception processing unit of the terminal device 1 determines, for each slot, whether the number of PDCCH candidates configured for that slot exceeds a first upper limit. Here, the PDCCH candidates to be adjusted are in a DCI format that uses a DCI format for single-slot scheduling (first DCI format). When the reception processing unit of the terminal device 1 determines that the number of PDCCH candidates configured for that slot exceeds the first upper limit, the reception processing unit drops (reduces, or decreases) one or more PDCCH candidates from the PDCCH candidates configured for that slot so that the number of PDCCH candidates monitored for that slot is within the first upper limit. When the reception processing unit of the terminal device 1 determines that the number of PDCCH candidates configured for that slot does not exceed the first upper limit, the reception processing unit does not drop (does not reduce, or decrease) the PDCCH candidates configured for that slot.

[0219] The reception processing unit of the terminal device 1 adjusts (drops, reduces, or decreases) the PDCCH candidates configured for multiple slots or the PDCCH candidates adjusted based on the first upper limit value so that the number of PDCCH candidates monitored in multiple slots does not exceed the second upper limit value. The reception processing unit of the terminal device 1 determines whether or not the sum of the PDCCH candidates configured for one or more slots and the PDCCH candidates adjusted based on the first upper limit value for one or more slots exceeds the second upper limit value. As described above, for slots in which a search space in which a DCI format for single-slot scheduling is configured is configured, the PDCCH candidates are adjusted based on the first upper limit value (including cases where the PDCCH candidates configured as a result of the determination based on the first upper limit value are not dropped (not reduced, or not decreased)), and the adjusted number of PDCCH candidates is used for the determination based on the second upper limit value. For slots in which a DCI format for single-slot scheduling is not configured and a search space in which a DCI format for multi-slot scheduling is configured, adjustment of PDCCH candidates based on the first upper limit value is not performed, and the number of configured PDCCH candidates is used for judgment based on the second upper limit value.

[0220] When the reception processing unit of the terminal device 1 determines that the sum of the PDCCH candidates configured for one or more slots and the PDCCH candidates adjusted based on the first upper limit value for one or more slots exceeds a second upper limit value, the reception processing unit drops one or more PDCCH candidates from the configured PDCCH candidates, or drops one or more PDCCH candidates from the adjusted PDCCH candidates, or drops one or more PDCCH candidates from each of the configured PDCCH candidates and the adjusted PDCCH candidates, to adjust the number of PDCCH candidates to be monitored so that the total number of PDCCH candidates to be monitored in the multiple slots is within the second upper limit value.When the reception processing unit of the terminal device 1 determines that the sum of the PDCCH candidates configured for one or more slots and the PDCCH candidates adjusted based on the first upper limit value for one or more slots does not exceed the second upper limit value, the reception processing unit does not drop the configured PDCCH candidates and the adjusted PDCCH candidates in the multiple slots, and monitors the PDCCH candidates. As described above, the SS determining unit of the base station device 3 determines the PDCCH candidates monitored by the reception processing unit of the terminal device 1. The base station device 3 transmits a PDCCH to the terminal device 1 using one of the determined PDCCH candidates.

[0221] The radio resource control layer processing unit 16 of the terminal device 1 configures a search area including at least a period, an offset, the number of PDCCH candidates for each aggregation level, and a DCI format, and configures PDCCH candidates of each DCI format for each slot based on RRC signaling indicating the configuration of multiple search areas. The radio resource control layer processing unit 36 ​​of the base station device 3 configures a search area including at least a period, an offset, the number of PDCCH candidates for each aggregation level, and a DCI format, for the terminal device 1, and configures PDCCH candidates of each DCI format for each slot for the terminal device 1, and generates RRC signaling indicating the configuration of multiple search areas.

[0222] As described above, one aspect of the present invention enables efficient transmission and reception of downlink control channels between the terminal device 1 and the base station device 3 while reducing the processing load on the terminal device 1. Single-slot scheduling can be efficiently supported while reducing the processing load on the terminal device 1 related to monitoring PDCCHs in multiple slots. In a situation where both multi-slot scheduling and single-slot scheduling are used, the load related to buffering received signals can be reduced by limiting the number of PDCCH candidates for single-slot scheduling to the number of PDCCH candidates that the terminal device 1 can process in a short time. The base station device 3 can flexibly set the configuration of a search space taking into account the situations of multiple terminal devices 1, while, when monitoring the configured PDCCH candidates locally exceeds the processing load of the downlink control channel in the terminal device 1, the monitoring process of the PDCCH candidates can be limited to within the processing capacity of the terminal device 1, thereby achieving efficient communication.

[0223] Various aspects of the device according to one aspect of this embodiment will be described below.

[0224] (1) In order to achieve the above object, one aspect of the present invention provides the following means. That is, a first aspect of the present invention is a terminal device including a processor and a memory that stores computer program code, the terminal device receiving RRC signaling indicating a configuration of a search space including at least a period, an offset, and the number of PDCCH candidates for each aggregation level, configuring PDCCH candidates for each slot based on the RRC signaling indicating the configuration of the search space, and adjusting the number of PDCCH candidates monitored in each slot using a first upper limit value, wherein if the number of PDCCH candidates configured for a slot exceeds the first upper limit value, at least some of the PDCCH candidates configured for that slot are dropped to set the number of PDCCH candidates monitored in that slot, and if the number of PDCCH candidates configured for a slot does not exceed the first upper limit value, adjusting the number of PDCCH candidates monitored in that slot. adjusting the number of PDCCH candidates monitored in the plurality of slots using a second upper limit value, wherein if a total number of PDCCH candidates adjusted based on the first upper limit value for the plurality of slots exceeds the second upper limit value, dropping at least some of the PDCCH candidates adjusted for at least one slot to set the number of PDCCH candidates monitored in the plurality of slots; and if a total number of PDCCH candidates set based on the first upper limit value for the plurality of slots does not exceed the second upper limit value, not dropping the PDCCH candidates adjusted based on the first upper limit value and setting the number of PDCCH candidates adjusted based on the first upper limit value for the plurality of slots.

[0225] (2) Furthermore, the PDCCH candidates whose number is adjusted based on the first upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling, and the PDCCH candidates whose number is adjusted based on the second upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling and PDCCH candidates that use a DCI format for multi-slot scheduling.

[0226] (3) A second aspect of the present invention is a base station device including a processor and a memory for storing computer program code, the base station device transmitting RRC signaling indicating a configuration of a search area including at least a period, an offset, and the number of PDCCH candidates for each aggregation level, the configuration of the search area including a plurality of search area configurations; configuring PDCCH candidates for each slot to a terminal device based on the RRC signaling indicating the configuration of the plurality of search areas; and determining the number of PDCCH candidates monitored in each slot using a first upper limit value in the terminal device, wherein if the number of PDCCH candidates configured for a slot exceeds the first upper limit value, at least a portion of the PDCCH candidates configured for that slot are dropped to determine the number of PDCCH candidates monitored in that slot; and if the number of PDCCH candidates configured for a slot does not exceed the first upper limit value, and performing operations including: determining the number of PDCCH candidates to be monitored in the slot without dropping the PDCCH candidates configured for that slot; determining the number of PDCCH candidates to be monitored in multiple slots using a second upper limit value in the terminal device, wherein if the total number of PDCCH candidates determined based on the first upper limit value for multiple slots exceeds the second upper limit value, dropping at least some of the PDCCH candidates determined for at least one slot to determine the number of PDCCH candidates to be monitored in the multiple slots; and if the total number of PDCCH candidates set based on the first upper limit value for multiple slots does not exceed the second upper limit value, not dropping the PDCCH candidates determined based on the first upper limit value and determining the number of PDCCH candidates determined based on the first upper limit value for multiple slots.

[0227] (4) Furthermore, the PDCCH candidates whose number is determined based on the first upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling, and the PDCCH candidates whose number is determined based on the second upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling and PDCCH candidates that use a DCI format for multi-slot scheduling.

[0228] (5) A third aspect of the present invention is a communication method used in a terminal device, comprising: a step of receiving RRC signaling indicating a configuration of a search area including at least a period, an offset, and a number of PDCCH candidates for each aggregation level; a step of configuring PDCCH candidates for each slot based on the RRC signaling indicating the configuration of the search area; and a step of adjusting the number of PDCCH candidates monitored in each slot using a first upper limit value, wherein if the number of PDCCH candidates configured for a slot exceeds the first upper limit value, at least a part of the PDCCH candidates configured for that slot are dropped to set the number of PDCCH candidates monitored in that slot; and if the number of PDCCH candidates configured for a slot does not exceed the first upper limit value, the number of PDCCH candidates configured for that slot is adjusted. adjusting the number of PDCCH candidates monitored in multiple slots using a second upper limit value, wherein, if a total number of PDCCH candidates adjusted based on the first upper limit value for multiple slots exceeds the second upper limit value, dropping at least some of the PDCCH candidates adjusted for at least one slot and setting the number of PDCCH candidates monitored in the multiple slots; and, if a total number of PDCCH candidates set based on the first upper limit value for multiple slots does not exceed the second upper limit value, not dropping the PDCCH candidates adjusted based on the first upper limit value and setting the number of PDCCH candidates adjusted based on the first upper limit value for multiple slots.

[0229] (6) Furthermore, the PDCCH candidates whose number is adjusted based on the first upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling, and the PDCCH candidates whose number is adjusted based on the second upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling and PDCCH candidates that use a DCI format for multi-slot scheduling.

[0230] (7) A fourth aspect of the present invention is a communication method used in a base station device, the method comprising the steps of: transmitting RRC signaling indicating a configuration of a search area including at least a period, an offset, and a number of PDCCH candidates for each aggregation level; configuring PDCCH candidates for each slot to a terminal device based on the RRC signaling indicating the configuration of the plurality of search areas; and determining the number of PDCCH candidates to be monitored in each slot using a first upper limit value in the terminal device, wherein if the number of PDCCH candidates configured for a slot exceeds the first upper limit value, dropping at least a portion of the PDCCH candidates configured for that slot to determine the number of PDCCH candidates to be monitored in that slot; and if the number of PDCCH candidates configured for a slot does not exceed the first upper limit value, dropping at least a portion of the PDCCH candidates configured for that slot to determine the number of PDCCH candidates to be monitored in that slot. and determining the number of PDCCH candidates monitored in a slot by using a second upper limit value in the terminal device, wherein, if the total number of PDCCH candidates determined based on the first upper limit value for a plurality of slots exceeds the second upper limit value, dropping at least some of the PDCCH candidates determined for at least one slot to determine the number of PDCCH candidates monitored in the plurality of slots, and if the total number of PDCCH candidates determined based on the first upper limit value for a plurality of slots does not exceed the second upper limit value, not dropping the PDCCH candidates determined based on the first upper limit value, and determining the number of PDCCH candidates determined based on the first upper limit value for a plurality of slots.

[0231] (8) Furthermore, the PDCCH candidates whose number is determined based on the first upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling, and the PDCCH candidates whose number is determined based on the second upper limit value are PDCCH candidates that use a DCI format for single-slot scheduling and PDCCH candidates that use a DCI format for multi-slot scheduling.

[0232] The programs running on the base station device 3 and terminal device 1 according to one aspect of the present invention may be programs (programs that cause a computer to function) that control a CPU (Central Processing Unit) or the like so as to realize the functions of the above-described embodiment according to one aspect of the present invention. 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) or HDD (Hard Disk Drive), and is read, modified, and written by the CPU as needed.

[0233] Note that the terminal device 1 and part of the base station device 3 in the above-described embodiment may be realized by a computer. In this case, a program for realizing this control function may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read into a computer system and executed to realize the control function.

[0234] The term "computer system" used here refers to a computer system built into the terminal device 1 or base station device 3, and includes hardware such as an OS and peripheral devices. Also, the term "computer-readable recording medium" refers to portable media such as flexible disks, optical magnetic disks, ROMs, and CD-ROMs, as well as storage devices such as hard disks built into the computer system.

[0235] Furthermore, the term "computer-readable recording medium" may include a medium that dynamically stores a program for a short period of time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, or a medium that stores a program for a certain period of time, such as a volatile memory within a computer system that serves as a server or client in such a case. The program may also be one that realizes part of the above-mentioned functions, or one that can realize the above-mentioned functions in combination with a program already recorded in the computer system.

[0236] The terminal device 1 may comprise at least one processor and at least one memory containing computer program instructions (computer programs). The memory and computer program instructions (computer programs) may be configured to cause the terminal device 1 to perform the operations and processes described in the above embodiments using the processor. The base station device 3 may comprise at least one processor and at least one memory containing computer program instructions (computer programs). The memory and computer program instructions (computer programs) may be configured to cause the base station device 3 to perform the operations and processes described in the above embodiments using the processor.

[0237] Furthermore, the base station device 3 in the above-described embodiment can also be realized as a collection (device group) consisting of multiple devices. Each of the devices constituting the device group may have some or all of the functions or functional blocks of the base station device 3 according to the above-described embodiment. It is sufficient for the device group to have all of the functions or functional blocks of the base station device 3. Furthermore, the terminal device 1 according to the above-described embodiment can also communicate with the base station device as a collection.

[0238] Furthermore, the base station device 3 in the above-described embodiments may be an EUTRAN (Evolved Universal Terrestrial Radio Access Network) and / or an NG-RAN (NextGen RAN, NR RAN). Furthermore, the base station device 3 in the above-described embodiments may have some or all of the functions of an upper node for an eNodeB and / or a gNB.

[0239] Furthermore, some or all of the terminal device 1 and base station device 3 in the above-described embodiments may be realized as an LSI, which is typically an integrated circuit, or as a chipset. Each functional block of the terminal device 1 and base station device 3 may be individually formed into a chip, or some or all of them may be integrated into a chip. Furthermore, the integrated circuit method is not limited to LSI, and may be realized using a dedicated circuit or a general-purpose processor. Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology, it is also possible to use an integrated circuit based on that technology.

[0240] Furthermore, in the above-described embodiment, a terminal device is described as an example of a communication device, but the present invention is not limited to this and can also be applied to terminal devices or communication devices such as stationary or non-movable electronic devices installed indoors or outdoors, for example, AV equipment, kitchen equipment, cleaning / washing equipment, air conditioning equipment, office equipment, vending machines, and other household appliances.

[0241] Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design modifications and the like are also included within the scope of the gist of the present invention. Furthermore, various modifications of one aspect of the present invention are possible within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. Furthermore, configurations in which elements described in the above embodiments are substituted with elements that achieve the same effect are also included. [Industrial Applicability]

[0242] One aspect of the present invention can be used in, for example, a communication system, a communication device (for example, a mobile phone device, a base station device, a wireless LAN device, or a sensor device), an integrated circuit (for example, a communication chip), or a program. [Explanation of symbols]

[0243] 1(1A, 1B, 1C) Terminal equipment 3 Base station equipment 10, 30 Radio transmitter / receiver 11, 31 Antenna section 12, 32 RF section 13, 33 Baseband section 14, 34 Upper layer processing unit 15, 35 Medium access control layer processing unit 16, 36 Radio resource control layer processing unit

Claims

1. A terminal device including a processor and a memory for storing computer program code, the terminal device receiving RRC signaling indicating a configuration of a search area including at least a period, an offset, and a number of PDCCH candidates for each aggregation level, configuring PDCCH candidates for each slot based on the RRC signaling indicating the configuration of the plurality of search areas, and adjusting the number of PDCCH candidates monitored in each slot using a first upper limit value, wherein if the number of PDCCH candidates configured for a slot exceeds the first upper limit value, dropping at least some of the PDCCH candidates configured for the slot to set the number of PDCCH candidates monitored in the slot, and if the number of PDCCH candidates configured for a slot does not exceed the first upper limit value, adjusting the number of PDCCH candidates configured for the slot to set the number of PDCCH candidates monitored in the slot. adjusting the number of PDCCH candidates to be monitored in multiple slots using a second upper limit value, wherein, if a total number of PDCCH candidates adjusted based on the first upper limit value for multiple slots exceeds the second upper limit value, dropping at least some of the PDCCH candidates adjusted for at least one slot to set the number of PDCCH candidates to be monitored in the multiple slots; and, if a total number of PDCCH candidates set based on the first upper limit value for multiple slots does not exceed the second upper limit value, not dropping the PDCCH candidates adjusted based on the first upper limit value, and setting the number of PDCCH candidates adjusted based on the first upper limit value for multiple slots.

2. The terminal device of claim 1, wherein the number of PDCCH candidates whose number is adjusted based on the first upper limit value is a PDCCH candidate that uses a DCI format for single-slot scheduling, and the number of PDCCH candidates whose number is adjusted based on the second upper limit value is a PDCCH candidate that uses a DCI format for single-slot scheduling and a PDCCH candidate that uses a DCI format for multi-slot scheduling.

3. A communication method used in a terminal device, comprising the steps of: receiving RRC signaling indicating a configuration of a search area, the configuration of the search area including at least a period, an offset, and a number of PDCCH candidates for each aggregation level; configuring PDCCH candidates for each slot based on the RRC signaling indicating the configuration of the plurality of search areas; and adjusting the number of PDCCH candidates monitored in each slot using a first upper limit value, wherein if the number of PDCCH candidates configured for a slot exceeds the first upper limit value, dropping at least some of the PDCCH candidates configured for the slot to set the number of PDCCH candidates monitored in the slot; and if the number of PDCCH candidates configured for a slot does not exceed the first upper limit value, adjusting the number of PDCCH candidates configured for the slot to set the number of PDCCH candidates monitored in the slot. adjusting the number of PDCCH candidates to be monitored in a plurality of slots using a second upper limit value, wherein, if a total number of PDCCH candidates adjusted based on the first upper limit value for a plurality of slots exceeds the second upper limit value, dropping at least some of the PDCCH candidates adjusted for at least one slot to set the number of PDCCH candidates to be monitored in the plurality of slots; and, if a total number of PDCCH candidates set based on the first upper limit value for a plurality of slots does not exceed the second upper limit value, not dropping the PDCCH candidates adjusted based on the first upper limit value and setting the number of PDCCH candidates adjusted based on the first upper limit value for a plurality of slots.

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