Terminal, base station, and wireless communication method

Abstract

A terminal includes: a reception section that receives search space information related to a search space associated with a control resource set; and a control section that controls monitoring of a downlink control channel using the search space during a predetermined period based on the search space information, the control section controlling monitoring of the downlink control channel that is repeatedly transmitted between different slots and / or within the same slot during the period based on repetition information related to repetition of the downlink control channel included in the search space information.

Description

[0001] Cross-references to related applications

[0002] This application is based on and claims priority to Japanese Patent Application No. 2021-004108, filed on January 14, 2021, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to terminals, base stations, and wireless communication methods. Background Technology

[0004] The Third Generation Partnership Project (3GPP) of the International Organization for Standardization, as a successor to Radio Access Technology (RAT) 3.9, namely Long Term Evolution (LTE), and RAT 4, namely LTE-Advanced, developed the 15th version of the specifications for RAT 5, namely New Radio (NR) (e.g., non-patent document 1).

[0005] In version 15, frequency utilization efficiency can be improved by setting a control resource set (CORESET) in at least a portion of the frequency band available to the terminal (e.g., User Equipment (UE)), compared to LTE, which sets a control area throughout the entire frequency band available to the terminal.

[0006] Existing technical documents

[0007] Non-patent literature

[0008] Non-patent document 1: 3GPP TS 38.300V15.9.0 (2020-03) Summary of the Invention

[0009] Currently, within 3GPP, research has begun on the functionality of IoT-oriented terminals that utilize NR for wireless access. For these IoT-oriented terminals, a narrower bandwidth is envisioned compared to the terminals introduced in Release 15. Schemes for repeatedly transmitting downlink control channels are also being investigated to compensate for the reduced coverage caused by this narrower bandwidth.

[0010] One of the purposes of this disclosure is to provide a terminal, base station, and wireless communication method capable of appropriately controlling the monitoring of repeatedly transmitted downlink control channels.

[0011] One aspect of this disclosure relates to a terminal comprising: a receiving unit that receives search space information relating to a search space associated with a control resource set; and a control unit that, based on the search space information, controls the monitoring of downlink control channels using the search space during a predetermined period. The control unit may also control the monitoring of downlink control channels repeatedly transmitted between different time slots and / or within the same time slot during the period based on repetition information related to the repetition of the downlink control channels contained in the search space information.

[0012] According to one method of this disclosure, it is possible to appropriately control the monitoring of the downlink control channel that is being repeatedly transmitted. Attached Figure Description

[0013] Figure 1 This is a diagram illustrating an example of a wireless communication system according to this embodiment.

[0014] Figure 2 This is a diagram illustrating an example of PDCCH monitoring in NR.

[0015] Figure 3 This is a diagram illustrating another example of PDCCH monitoring in NR.

[0016] Figure 4 This is a diagram illustrating a first example of time slot repetition involved in this embodiment.

[0017] Figure 5 This is a diagram illustrating a second example of time-slot repetition involved in this embodiment.

[0018] Figure 6 This is a diagram illustrating a third example of inter-slot repetition involved in this embodiment.

[0019] Figure 7 This is a diagram illustrating a first example of time-slot repetition involved in this embodiment.

[0020] Figure 8 This is a diagram illustrating an example of a combination of inter-slot repetition and intra-slot repetition involved in this embodiment.

[0021] Figure 9 This is a diagram illustrating an example of search space information involved in this embodiment.

[0022] Figure 10 This is a diagram illustrating an example of the derivation of the number of repetitions involved in this embodiment.

[0023] Figure 11 This is a diagram illustrating a first defined example of frequency domain resources for repetition according to this embodiment.

[0024] Figure 12 This is a diagram illustrating a first example of CORESET information related to this embodiment.

[0025] Figure 13 This is a diagram illustrating a second specific example of frequency domain resources for repetition according to this embodiment.

[0026] Figure 14 This is a diagram illustrating a second example of CORESET information related to this embodiment.

[0027] Figure 15 This is a diagram illustrating a second specific example of frequency domain resources for repetition according to this embodiment.

[0028] Figure 16 This is a diagram illustrating a third example of CORESET information related to this embodiment.

[0029] Figure 17 This is a diagram illustrating a fourth example of determining frequency domain resources for repetition according to this embodiment.

[0030] Figure 18 This is a diagram illustrating a fifth determined example of frequency domain resources for repetition according to this embodiment.

[0031] Figure 19 This is a diagram illustrating an example of search space information involved in this embodiment.

[0032] Figure 20 This is a diagram illustrating an example of the PDCCH information involved in this embodiment.

[0033] Figure 21 This diagram illustrates an example of repeated transmission of a frequency-hopping PDCCH according to this embodiment.

[0034] Figure 22 This diagram illustrates an example of the switching of search space groups involved in this embodiment.

[0035] Figure 23 This is a diagram illustrating an example of a DCI for switching control of search space groups according to this embodiment.

[0036] Figure 24 This is a diagram illustrating an example of the value of the search group switching field involved in this embodiment.

[0037] Figure 25 This is a diagram illustrating an example of the hardware structure of each device within the wireless communication system according to this embodiment.

[0038] Figure 26 This is a diagram illustrating an example of the functional block structure of the terminal involved in this embodiment.

[0039] Figure 27 This is a diagram illustrating an example of the functional block structure of a base station according to this embodiment.

[0040] Figure 28 This is a diagram illustrating an example of PDCCH monitoring operation in a wireless communication system according to this embodiment.

[0041] Figure 29 This is a diagram illustrating an example of a search space group switching operation in a wireless communication system according to this embodiment. Detailed Implementation

[0042] Embodiments of this disclosure will be described with reference to the accompanying drawings. Furthermore, components labeled with the same reference numerals in the drawings may have the same or similar structures.

[0043] Figure 1 This is a diagram illustrating an example of a wireless communication system according to this embodiment. Figure 1 As shown, the wireless communication system 1 may include a terminal 10, a base station 20, and a core network 30. Furthermore, Figure 1 The number of terminals 10 and base stations 20 shown is only an example and is not limited to the number shown.

[0044] As a wireless access technology (RAT) for wireless communication system 1, NR can be envisioned, but is not limited to it; for example, various RATs such as RATs of the sixth generation or later can be utilized.

[0045] Terminal 10 is, for example, a smartphone, personal computer, vehicle-mounted terminal, vehicle-mounted device, stationary device, telematics control unit (TCU), or other predetermined terminal or device. Terminal 10 may also be referred to as User Equipment (UE), Mobile Station (MS), User Terminal, Radio Apparatus, Subscriber Terminal, Access Terminal, etc. Terminal 10 can be mobile or fixed. As a Radio Access Terminal (RAT), Terminal 10 can be configured to communicate using Radio Frequency (NR).

[0046] Base station 20 forms one or more cells C and uses these cells C to communicate with terminal 10. Cell C can also be referred to interchangeably with serving cell, carrier, component carrier (CC), etc. Base station 20 can be called gNodeB (gNB), en-gNB, Next Generation-Radio Access Network (NG-RAN) node, low-power node, Central Unit (CU), Distributed Unit (DU), gNB-DU, Remote Radio Head (RRH), Integrated Access and Backhaul / Backhauling (IAB) node, etc. Base station 20 is not limited to being composed of a single node; it can also be composed of multiple nodes (e.g., a combination of lower-level nodes such as DU and upper-level nodes such as CU).

[0047] The core network 30 may be, for example, a 5G Core Network (5GC) that supports NR, but is not limited to this. Devices on the core network 30 (hereinafter also referred to as "core network devices") perform mobility management functions such as paging and location registration for the terminal 10. The core network devices may also be connected to the base station 20 via a predetermined interface (e.g., an S1 or NG interface).

[0048] The core network apparatus may also include, for example, at least one of an Access and Mobility Management Function (AMF) that manages C-plane information (e.g., information related to access and mobility management) and a User Plane Function (UPF) that performs transmission control of U-plane information (e.g., user data).

[0049] In wireless communication system 1, terminal 10 receives downlink (DL) signals and / or transmits uplink (UL) signals from base station 20. Terminal 10 can be configured with one or more carriers. The bandwidth of each carrier is, for example, from 5 MHz to 400 MHz. A carrier can be configured with one or more bandwidth parts (BWPs). A BWP has at least a portion of the carrier's bandwidth.

[0050] A BWP can also be configured with one or more Control Resource Sets (CORESETs). A CORESET is a time-domain and frequency-domain resource used in the transmission of the downlink control channel. For example, a CORESET consists of a predetermined number of symbols (e.g., 1 to 3 symbols) and a predetermined number of resource blocks (RBs) (e.g., 6n (n≥1) RBs).

[0051] Although the following description uses the Physical Downlink Control Channel (PDCCH) as an example of a downlink control channel, any channel used in the transmission of downlink control information (DCI) is acceptable, and its name is not limited to PDCCH.

[0052] A CORESET comprises multiple Control Channel Elements (CCEs). A CCE consists of a predetermined number of Resource Element Groups (REGs). For example, a REG can consist of one RB (i.e., one symbol and 12 subcarriers), and a CCE can consist of six REGs (i.e., six RBs).

[0053] The candidate resources for configuring PDCCH (hereinafter referred to as "PDCCH candidates") consist of a predetermined number of CCEs corresponding to the aggregation level (AL). For example, if AL=1, then one PDCCH candidate consists of one CCE, and if AL=2, then one PDCCH candidate consists of two CCEs.

[0054] The search space comprises PDCCH candidates consisting of one or more CCEs within a CORESET associated with the search space. Therefore, it can be said that the search space is composed of at least a portion of the CORESETs associated with the search space. Terminal 10 monitors each PDCCH candidate included in the search space to detect DCIs.

[0055] Here, monitoring refers to DCI decoding of each PDCCH candidate within the search space according to a predetermined format, known as "blind decoding." Additionally, the search space may include a common search space (CSS) and a UE-specific search space (USS). The common search space is a common search space for one or more terminals 10, while the UE-specific search space is a search space specific to one terminal 10. The search space described above can be provided for each AL, and the set of search spaces for one or more ALs can be called a search space set. In this specification, "search space" can refer to the search space of a specific AL or a search space set.

[0056] The base station 20 provides terminal 10 with information related to each CORESET (hereinafter referred to as "CORESET information"). This CORESET information may, for example, be a Radio Resource Control (RRC) Information Element (IE) "ControlResourceSet". Here, IE may also be referred to as a parameter. The CORESET information may include, for example, at least one of the following.

[0057] • CORESET identification information (e.g., RRC IE "controlResourceSetId")

[0058] • Period information indicating the period of CORESET (hereinafter referred to as "CORESET period") (e.g., RRC IE "duration")

[0059] • Indicates frequency domain resource information that constitutes the frequency domain resources of CORESET (e.g., RRC IE "frequencyDomainResources").

[0060] Additionally, the base station 20 provides the terminal 10 with information related to each search space (hereinafter referred to as "search space information"). This search space information may, for example, be RRC IE "SearchSpace". The search space information may include at least one of the following.

[0061] • Search space identification information (e.g., RRC IE "searchSpaceId")

[0062] • Identification information of the CORESET associated with the search space (e.g., RRC IE "controlResourceSetId")

[0063] • Period / offset information (e.g., RRC IE “monitoringSlotPeriodicityAndOffset”) indicates the period k and offset o used to monitor the PDCCH. Hereinafter, the period k and offset o will be referred to as monitoring period k and monitoring offset o, respectively.

[0064] • Monitoring period information (e.g., RRC IE “duration”) indicates the period T during which the PDCCH is monitored, hereinafter referred to as the monitoring period T.

[0065] • Monitor symbol information (e.g., RRC IE "monitoring SymbolsWithinSlot"), indicating the first symbol of the PDCCH to be monitored within the slot.

[0066] • Search space group information (e.g., RRC IE “searchSpaceGroupIdList”) indicates one or more groups (hereinafter referred to as “search space groups”) associated with the search space.

[0067] Terminal 10 controls the monitoring of PDCCH based on the aforementioned CORESET information and search space information. Figure 2 This is a diagram illustrating an example of PDCCH monitoring in NR. For example, Figure 2 This illustrates an example of PDCCH monitoring using search space #1 associated with CORESET#1.

[0068] exist Figure 2 For example, the monitoring period k is 10 time slots, and the monitoring period T is 4 time slots. In addition, it is assumed that the CORESET period associated with search space #1 for CORESET#1 is two symbols, and the frequency domain resources for CORESET#1 are 6n (n≥1) RBs.

[0069] Terminal 10 is based on radio frame number n f The wireless frame #n f The time slot number n s，f The number of time slots N in a wireless frame s，f The monitoring period k and monitoring offset o are used to determine the starting time slot during the monitoring period. For example, terminal 10 will select a time slot with a time slot number that satisfies the following formula (1). Figure 2 The time slot #0 in the data is determined as the starting time slot during the monitoring period.

[0070] (Formula 1)

[0071] (n f ·N s，f +n s，f -o)mod k=0

[0072] in addition, Figure 2 This is just an example; the wireless frame number n f The wireless frame #n f The time slot number n s，f The number of time slots N in a wireless frame s，f The monitoring period k and monitoring offset o are not limited to the examples shown in the figure. For example, although in Figure 2 The following example illustrates a subcarrier spacing (SCS) of 15 kHz, therefore the number of time slots N within a radio frame is... s，f =10, but not limited to this. When using SCS greater than 15kHz (e.g., 30kHz, 60kHz, 120kHz, etc.), the number of time slots N within a radio frame... s，f Increase.

[0073] In addition, Figure 2 Regarding the monitoring symbol information shown, in the bits corresponding to symbols #0 to #13 respectively, the bit corresponding to symbol #0 is "1". Therefore, in each time slot during the monitoring period (hereinafter referred to as "monitoring time slot"), CORESET #1 associated with search space #1 is configured in two symbols with symbol #0 as the starting position. As described above, search space #1 is at least a part of CORESET #1 associated with search space #1.

[0074] Terminal 10 uses T consecutive time slots, starting from the initial time slot #0 as determined above, as monitoring time slots to monitor each PDCCH candidate within the search space #1. Terminal 10 detects the PDCCH for itself by monitoring each PDCCH candidate in the search space #1. This PDCCH detection can be described as the detection of a predetermined format DCI with scrambled Cyclic Redundancy Check (CRC) using a predetermined Radio Network Temporary Identifier (RNTI).

[0075] Additionally, the DCI format may also include a DCI format for downlink shared channel scheduling (e.g., DCI format 1_X), a DCI format for uplink shared channel scheduling (e.g., DCI format 0_X), and a DCI format for purposes different from scheduling (e.g., DCI format 2_X), etc. Here, X is a positive integer.

[0076] Figure 3 This is another example of PDCCH monitoring in NR. For example, Figure 3This illustrates an example of PDCCH monitoring using search space #2 associated with CORESET#2. Figure 3 In this respect, configuring multiple search spaces in each time slot during the monitoring period differs from configuring a single search space. Figure 2 Different. Figure 3 In, with Figure 2 The explanation will focus on the differences.

[0077] exist Figure 3 In this context, the CORESET period for CORESET#2 is a single symbol. Regarding the monitoring symbol information, in the bits corresponding to symbols #0 through #13, the bits corresponding to symbols #0 and #7 are "1". Therefore, in each time slot during the monitoring period, CORESET#2 associated with search space #2 is configured in one symbol, starting at symbols #0 and #7 respectively.

[0078] Terminal 10 monitors each PDCCH candidate within the search space #2 of symbols #0 and #7 in each time slot during the monitoring period. Figure 3 In the middle, terminal 10 did not detect PDCCH in search space #2 of symbol #0, but detected PDCCH in search space #2 of symbol #7.

[0079] Thus, in NR, terminal 10 monitors the PDCCH during a monitoring period configured with a predetermined cycle. Alternatively, it is also possible to configure more than one search space in each time slot during the monitoring period, and terminal 10 monitors more than one search space in each time slot.

[0080] Here, in NR Release 17, research supports features for terminals with lower performance and price ranges compared to those introduced in Release 15 or 16 for enhanced Mobile Broadband (eMBB) and ultra-reliable and low-latency communications (URLLC). These terminals are also known as reduced-capability (RedCap) terminals or devices, and for example, can be used in industrial wireless sensors, video surveillance, and wearable devices.

[0081] Assuming RedCap terminals offer higher performance than those designed for Low Power Wide Area (LPWA), the carriers utilized by RedCap terminals could be, for example, 20MHz, 50MHz, or 100MHz bandwidth. Furthermore, LPWA includes, for example, Long Term Evolution for Machine-type Communication (LTE-M) operating with RAT in Category 1 LTE mode, and Narrow Band IoT (NB-IoT). Category 1 has a maximum bandwidth of 20MHz, LTE-M has a maximum bandwidth of 1.4MHz (6RB), and NB-IoT has a maximum bandwidth of 180kHz (1RB). Therefore, RedCap terminals can also be used as middle-range terminals between those for eMBB, URLLC, and LPWA.

[0082] In the case of RedCap terminal as terminal 10, a scheme for repeatedly transmitting PDCCH is studied to compensate for the reduced coverage caused by narrower carrier bandwidth. Specifically, it is assumed that base station 20 repeatedly transmits PDCCH in the time domain and / or frequency domain.

[0083] However, terminal 10 assumes that the first PDCCH transmitted in each search space configured during the monitoring period of a predetermined period will be transmitted for PDCCH reception processing (e.g., demodulation, decoding, etc.). Therefore, if the PDCCH is repeatedly transmitted, terminal 10 may not be able to properly monitor the repeatedly transmitted PDCCH using existing monitoring methods.

[0084] Therefore, in this embodiment, (1) monitoring of PDCCHs repeatedly transmitted using different time-domain resources (hereinafter referred to as "first PDCCH monitoring"), (2) monitoring of PDCCHs transmitted using different frequency-domain resources (hereinafter referred to as "second PDCCH monitoring"), and (3) a combination of first PDCCH monitoring and second PDCCH monitoring are described. In addition, in this embodiment, (4) control related to the switching of search space groups (hereinafter referred to as "switching control") is also described.

[0085] (1) First PDCCH monitoring

[0086] In the first PDCCH monitoring, the monitoring of PDCCHs repeatedly transmitted in the time domain is described. Terminal 10 controls the monitoring of PDCCHs repeatedly transmitted using different time domain resources during a predetermined monitoring period T based on information related to PDCCH repetition contained in the search space information (hereinafter referred to as "repetition information").

[0087] Here, different time-domain resources can be, for example, different time slots within a predetermined monitoring period T, or different symbols within the same time slot within the same monitoring period T. Therefore, PDCCH can be repeated between different time slots within more than one monitoring period (hereinafter referred to as "inter-slot repetition"), or it can be repeated within the same time slot within the monitoring period (hereinafter referred to as "intra-slot repetition").

[0088] Alternatively, the repetition information may include information indicating the number of repetitions R of the PDCCH, or it may include information indicating the maximum value of that number of repetitions R. In the latter case, terminal 10 can determine the number of repetitions R based on the maximum value and a predetermined field value in the DCI. Furthermore, the number of repetitions R may also be referred to as the repetition level, etc.

[0089] Additionally, the repetition information may also include information indicating the start time slot of the PDCCH repetition (hereinafter referred to as "start time slot information"). Furthermore, in the case of repetition within a time slot, the repetition information may also include information indicating the symbols of the PDCCH repetition (hereinafter referred to as "repetition symbol information").

[0090] Based on the repetition information described above, terminal 10 can configure the search space used for monitoring PDCCHs transmitted via inter-slot repetition and / or intra-slot repetition. Terminal 10 can also detect a PDCCH by monitoring PDCCH candidates within the configured search space.

[0091] Thus, when a PDCCH is transmitted repeatedly, since the search space for monitoring that PDCCH is also configured repeatedly, the repetition of the PDCCH can also be referred to as the repetition of the search space. Hereinafter, this search space will also be referred to as the "repetition search space".

[0092] (1.1) Inter-slot repetition

[0093] Inter-slot repetition can be applied to multiple time slots within a single monitoring period T within a predetermined period of monitoring, or it can be applied to multiple time slots across multiple monitoring periods T within a predetermined period of monitoring.

[0094] In inter-slot repetition, based on the number of PDCCH repetitions R, the monitoring slots #k for the 1st to Rth PDCCH transmissions within the predetermined monitoring period T are determined. i (i = 0, ..., R-1). Specifically, in addition to being based on the number of repetitions R, terminal 10 can also be based on the start time slot #k0 of the repetition and the radio frame number n. fThe wireless frame #n f The time slot number n s，f The number of time slots N in a wireless frame s，f The monitoring time slot #k is determined by at least one of the following: monitoring period k, monitoring interval T, and monitoring offset o. i (i = 0, ..., R-1). For example, terminal 10 can have time slot numbers that satisfy the following formula (2), starting from k0 up to k R-1 The continuous time slots are defined as monitoring time slot #k i (i = 0, ..., R-1).

[0095] [Mathematical Expression 1]

[0096] (Formula 2)

[0097]

[0098] Furthermore, the repeated start time slot #k0 can also be explicitly notified to the terminal 10 from the base station 20 through the aforementioned start time slot information. Alternatively, the terminal 10 can deduce the start time slot #k0 itself based on implicit information without explicit notification of the aforementioned start time slot information. For example, the terminal 10 can regard the start time slot of the monitoring period T as the repeated start time slot #k0.

[0099] Figure 4 This is a diagram illustrating a first example of inter-slot repetition involved in this embodiment. Figure 4 In, as referenced Figure 2 As explained, based on the search space information of search space #1, the monitoring period T of search space #1 is allocated to time slots #0 to #3 of each radio frame. Furthermore, based on the CORESET information of CORESET #1 associated with search space #1, CORESET #1 is allocated to two symbols starting from symbol #0 of each time slot within the monitoring period T. This search space #1 is used as a reused search space.

[0100] For example, in Figure 4 In this configuration, the PDCCH repetition count R is 2, and the starting time slot #k0 of the repetition is the same as the starting time slot #0 of the predetermined monitoring period T. Terminal 10 assumes that the PDCCH with a repetition count R is transmitted over R consecutive time slots starting from the starting time slot #k0 of the repetition. Figure 4 In this context, since R=2, terminal 10 assumes that the first PDCCH and the second PDCCH are mapped in the search space #1 of each time slot #k0 and #k1, and monitors the search space #1 of each time slot #k0 and #k1.

[0101] For example, in Figure 4In this process, terminal 10 detects the first PDCCH by monitoring the search space #1 of time slot #k0, and detects the second PDCCH by monitoring the search space #1 of time slot #k1. In time slot #k... i If the (i+1)th PDCCH is successfully decoded in (0≤i≤R-1), terminal 10 can abort slot #k. i+1 The monitoring of search space #1 can continue, or monitoring can continue to correspond to the number of repetitions R. In addition, in order to decode the (i+1)th PDCCH, terminal 10 can also synthesize the PDCCH from the 1st to the (i+1)th PDCCH.

[0102] Figure 5 This is a diagram illustrating a second example of time-slot repetition involved in this embodiment. Figure 5 Prerequisites and Figure 4 Same, and will be with Figure 4 The explanation will focus on the differences. Figure 5 In this process, terminal 10 determines the repeating start time slot #k0 based on the start time slot information from base station 20. The start time slot information may be, for example, the period and offset of the repeating start time slot, or it may be the offset of the start time slot from the monitoring period T.

[0103] For example, in Figure 5 In this context, the starting time slot information indicates the offset (here, 2) from the starting time slot #0 during the monitoring period T. Terminal 10, based on the starting time slot #0 of the monitoring period T determined by the above formula (1) and the offset "2" indicated by the starting time slot information, determines the repeating starting time slot #k0 as time slot #2. Figure 5 In this case, the number of repetitions R = 4, and the time slot #3 for the search space #1 used for the second PDCCH is the final time slot of the monitoring period T. Therefore, the search space #1 used for the third and fourth PDCCHs is set in time slots #0 and #1 of the next monitoring period T.

[0104] In this way, terminal 10 increments the time slot number by 1, starting from the repeating initial time slot #k0 (in this case, time slot #2 of radio frame #0), to determine the monitoring time slot #k. i (0≤i≤R-1), if monitoring time slot #k i+1 If the time slot becomes a time slot other than T during the monitoring period (in this case, time slot #4 of radio frame #0), then the monitoring time slot #k can be... i+1 The starting time slot for the next monitoring period is determined (in this case, time slot #0 of radio frame #1 after time slot #4 of radio frame #0). Terminal 10 can increment i by 1 each time to repeat the above process until i equals the number of repetitions R-1. Thus, R monitoring time slots #k0 to #k... R-1 It can span multiple monitoring periods.

[0105] Figure 6 This is a diagram illustrating a third example of inter-slot repetition involved in this embodiment. Figure 6 In, as referenced Figure 3 As explained, based on the search space information of search space #2, the monitoring period T of search space #2 is configured in time slots #0 to #3 of each radio frame. Furthermore, based on the CORESET information of CORESET #2 associated with search space #2, CORESET #2 is configured in symbols #0 and #7 of each time slot within the monitoring period T. This search space #2 is used as a reused search space.

[0106] exist Figure 6 In the monitoring time slots #k used for repetition i In setting multiple search spaces in (i = 0, ..., R-1), this is consistent with... Figure 4 and Figure 5 Different. For example... Figure 6 As shown, in each monitoring time slot #k i Different PDCCHs are transmitted within multiple search spaces. Furthermore, different PDCCHs can also be PDCCHs that transmit different DCIs.

[0107] For example, in Figure 6 In the process, the first PDCCH#1 is mapped within the search space #2 of symbol #0 in monitoring time slot #k0, and the first PDCCH#2 is mapped within the search space #2 of symbol #7 in monitoring time slot #k1. Furthermore, the second PDCCH#1 is mapped within the search space #2 of symbol #0 in the next monitoring time slot #k1, and the second PDCCH#2 is mapped within the search space #2 of symbol #7 in monitoring time slot #k1.

[0108] Thus, in the inter-slot repetition, in the R monitoring time slots #k used for repetition i When multiple search spaces are set in (i = 0, ..., R-1), multiple PDCCHs can be repeated between monitoring time slots by mapping different PDCCHs in these multiple search spaces.

[0109] (1.2) Repetition within a time slot

[0110] Repetition within a time slot can also be applied to different symbols within the same time slot during a predetermined monitoring period T. The following explanation will focus on the differences from (1.1) above.

[0111] In the case of intra-slot repetition, base station 20 sends repetition symbol information to terminal 10, which indicates the symbols in which PDCCH is repeated within a time slot (i.e., the PDCCH is sent after the second time). Based on the aforementioned monitoring symbol information and repetition symbol information, terminal 10 controls the monitoring of PDCCHs that are repeatedly sent among multiple symbols in the same time slot.

[0112] Figure 7 This is a diagram illustrating a first example of time-slot repetition involved in this embodiment. Figure 7 In this context, based on the search space information of search space #3, the monitoring period T of search space #3 is configured in time slots #0 to #3 of each radio frame. Additionally, based on the CORESET information of CORESET #3 associated with search space #3, CORESET #3 is configured in symbols #0, #4, #8, and #12 of each monitoring time slot. This search space #3 is used as a reused search space.

[0113] refer to Figure 7 The monitoring symbol information within the aforementioned search space information indicates the initial symbols #0, #4, #8, and #12 configured for search space #3. Additionally, the repeated symbol information within the aforementioned search space information indicates the initial symbols #4 and #12 configured for search space #3 used in subsequent PDCCH monitoring. For example, in... Figure 7 In this context, the repeating symbol information is a 14-bit bitmap corresponding to symbols #0 to #13 respectively, and the bits corresponding to symbols #4 and #12 are "1". Therefore, terminal 10 assumes that the first PDCCH is mapped in search space #3 of symbol #0, and the second PDCCH is mapped in search space #3 of symbol #4. Symbols #8 and #12 are also the same as symbols #0 and #4.

[0114] In addition, Figure 7 In the repeated symbol information, the bit corresponding to the first symbol of the PDCCH that can be configured after the second transmission within one time slot is set to "1", and the bit corresponding to the first symbol of the PDCCH that can be configured for the first transmission is set to "0", but it is not limited to this. The repeated symbol information can be any information that can identify whether it is a symbol of the PDCCH that can be configured for the first transmission or the PDCCH that can be configured after the second transmission. For example, it can also be that the bit corresponding to the first symbol of the PDCCH that can be configured after the second transmission within one time slot is set to "0", and the bit corresponding to the first symbol of the PDCCH that can be configured for the first transmission is set to "1".

[0115] (1.3) Combination of inter-slot repetition and intra-slot repetition

[0116] The inter-slot repetition and intra-slot repetition described above can also be combined. Specifically, terminal 10 can monitor more than one PDCCH that is repeatedly transmitted across multiple symbols in multiple monitoring time slots.

[0117] Figure 8 This diagram illustrates an example of a combination of inter-slot repetition and intra-slot repetition involved in this embodiment. Figure 8 In the middle, although with Figure 7 The search space #3 and CORESET #3 are configured similarly, but the number of repetitions R=7 is the same as... Figure 7 Different. In the following text, with respect to... Figure 7 The explanation will focus on the differences. Figure 8 In the middle, the repeated symbol information indicates that the search space #3 used for monitoring PDCCH after the second time is configured with the first symbols #4, #8 and #12.

[0118] like Figure 8 As shown, the pattern of symbols transmitted by the PDCCH after the second time, as indicated by the repeated symbol information, can also span multiple monitoring slots #k. i (0≤i≤R s -1) Repeated. Here, the number of repetitions R is the number of monitoring time slots R used by the PDCCH. s The number of repetitions R and the number n of search spaces within a time slot that can map subsequent PDCCHs can be determined based on the number of repetitions R and a time slot. ss Derivation, for example, through ceil{(R-1) / n ss Derivation. In Figure 8 In this case, since the number of repetitions R is 7, the number of search spaces n ss The value is 3, therefore R s The value is ceil{(7-1) / 3}=2.

[0119] In addition, although Figure 8 In this context, monitoring time slots #k0 and #k1 are included in different monitoring periods, but of course they can also be included in the same monitoring period.

[0120] (1.4) Signaling for duplicate messages

[0121] Next, the signaling for the repeat information used in the first PDCCH monitoring will be explained. As mentioned above, the repeat information may include at least one of the following: information indicating the number of repeats R of the PDCCH, information indicating the maximum value of the number of repeats R, start time slot information, and repeat symbol information.

[0122] Repeat information can be sent from base station 20 to terminal 10 using higher layer parameters. Higher layer parameters can be parameters of the RRC layer (e.g., RRC IE) or parameters of the Medium Access Control (MAC) layer (e.g., Medium Access Control Element (MAC CE)).

[0123] Figure 9 This is a diagram illustrating an example of search space information involved in this embodiment. Figure 9 An example is shown where the RRC IE “SearchSpace”, which serves as search space information, contains the aforementioned repetition information. Here, as repetition information, information indicating the number of repetitions R (e.g., RRC IE “numRepetition-r17”) and repetition symbol information (e.g., RRC IE “repetitionSymbolsWithinSlot-r17”) are shown.

[0124] like Figure 9 As shown, the number of repetitions R can be any of 1, 2, 4, 8, 16, 32, 64, 128, or 256. Furthermore, the RRC IE “repetitionSymbolsWithinSlot-r17”, which serves as the repetition symbol information, can be a 14-bit bitmap.

[0125] also, Figure 9 As just one example, the RRC IE "SearchSpace" can also include information indicating the maximum value of the number of repetitions R of the PDCCH (instead of including information indicating that number of repetitions R) as repetition information. Additionally, the RRC IE "SearchSpace" can also include start slot information.

[0126] Figure 10 This is a diagram illustrating an example of the derivation of the number of repetitions involved in this embodiment. Figure 10 An example is shown where the search space information (e.g., RRC IE “SearchSpace”) contains information indicating the maximum value of the number of repetitions R of PDCCH.

[0127] Terminal 10 can also determine the number of repetitions R of the PDCCH based on the values ​​of predetermined fields within the DCI and the aforementioned maximum value rep_max. For example, in Figure 10 In the DCI, the values ​​of predetermined fields are associated with parameters r1 to r4 used to derive the number of repetitions R. Terminal 10 determines the number of repetitions R based on the aforementioned maximum value rep_max and these parameters.

[0128] For example, in Figure 10 In the PDCCH, when the maximum value of the repetition count R, rep_max, is 8, if the value of a predetermined field in the DCI is "00", then the repetition count R = rep_max / 8 = 1. Similarly, if the value of a predetermined field in the DCI is "01", "10", or "11", then the repetition count R = 2, 4, or 8.

[0129] like Figure 10 As shown, by dynamically specifying the number of repetitions R of PDCCH based on DCI, the coverage extension range can be controlled more flexibly.

[0130] As described above, in the first PDCCH monitoring, since the reuse search space is configured based on the repetition information contained in the search space information, it is possible to appropriately control the monitoring of PDCCHs that are repeatedly transmitted using different time-domain resources during a monitoring period of a predetermined period.

[0131] (2) Second PDCCH monitoring

[0132] In the second PDCCH monitoring, the monitoring of PDCCHs that are repeatedly transmitted in the frequency domain is described. Terminal 10 controls the monitoring of PDCCHs that are repeatedly transmitted between multiple frequency domain resources corresponding to more than one CORESET.

[0133] The reusable search space used in the monitoring of this PDCCH can be associated with a single CORESET (see 2.1 below) or multiple CORESETs (see 2.2 below).

[0134] (2.1) Reusable search space associated with a single CORESET

[0135] If the reuse search space is associated with a single CORESET, then multiple frequency domain resources for repeatedly transmitting PDCCH can also correspond to that single CORESET.

[0136] The CORESET information related to the CORESET may include multiple frequency domain resource information indicating the multiple frequency domain resources respectively (see 2.1.1 below), or it may include frequency domain resource information indicating one of the multiple frequency domain resources and repetition number information indicating the number of repetitions of the PDCCH (see 2.1.2 below), or it may include frequency domain resource information indicating one of the multiple frequency domain resources and offset information indicating the offset (see 2.1.3 below).

[0137] (2.1.1) First example of determining repetitive frequency domain resources

[0138] In the first determined example, terminal 10 determines multiple frequency domain resources for the CORESET based on multiple frequency domain resource information contained in the CORESET information related to a single CORESET.

[0139] Figure 11 This is a diagram illustrating a first defined example of a frequency domain resource for repetition according to this embodiment. For example, in Figure 11 In this context, CORESET#1 is associated with search space #1, which is used as a reuse search space. Suppose that the CORESET information for CORESET#1 includes, in addition to the frequency domain resource information indicating the frequency domain resource #0 for CORESET#1, frequency domain resource information 1 and 2 respectively indicating the frequency domain resources #1 and #2 for CORESET#1.

[0140] Frequency domain resource information, frequency domain resource information 1, 2 can also be bitmaps that each include bits corresponding to a predetermined number of RB groups (hereinafter referred to as "RB groups"). The length of this bitmap can also be determined based on the number of RBs constituting the BWP and the number of RBs constituting one RB group. Although in Figure 11 A group of RBs is defined as consisting of 6 consecutive RBs, but it is not limited to this; a group of RBs can consist of more than one RB.

[0141] Alternatively, in the frequency domain resource information, frequency domain resource information 1 and 2, the bits corresponding to the RB groups constituting frequency domain resources #0, #1 and #2 are set to "1", and the bits corresponding to other RB groups are set to "0". Note that it is also possible that frequency domain resources #0, #1 and #2 used for the same CORESET #1 are composed of different RB groups, and duplicate RB groups are not allowed.

[0142] like Figure 11 As shown, terminal 10 can also be configured with search space #1 in each of the frequency domain resources #0, #1 and #2 for CORESET#1. Terminal 10 can also use search space #1 to control the monitoring of the (i+1)th PDCCH transmitted in frequency domain resource #i (where 0≤i≤2).

[0143] In addition, although Figure 11 The CORESET period of CORESET#1, which consists of different frequency domain resources #0, #1, and #2, is the same, but it is not limited to this and can also be different. Thus, the CORESET period of CORESET#1 can be a common period for multiple frequency domain resources of CORESET#1, or it can be configured separately for each frequency domain resource of CORESET#1.

[0144] Figure 12This is a diagram illustrating a first example of the CORESET information involved in this embodiment. For example, in Figure 12 The example shown is an RRC IE “ControlResourceSet” containing multiple frequency domain resource information that respectively indicate multiple frequency domain resources for a CORESET identified by the RRC IE “controlResourceSetId”.

[0145] For example, in Figure 12 In the RRC IE “ControlResourceSet” shown, the frequency domain resources used for the first transmission (1st time) can be indicated by the RRC IE “frequencyDomainResources”. On the other hand, the frequency domain resources used for the second and subsequent transmissions can be indicated by the RRC IE “frequencyDomainResourcesRepetition-r17”.

[0146] Thus, the CORESET information may include, in addition to the frequency domain resource information for the initial transmission (e.g., RRC IE "frequencyDomainResources"), a list of frequency domain resource information for subsequent transmissions (e.g., RRC IE "frequencyDomainResourcesRepetition-r17"). The number of entries in this list may, for example, be equal to the repetition number R-1. Each entry in the frequency domain resource information for subsequent transmissions may also indicate an RB group that does not overlap with the frequency domain resource information for the initial transmission.

[0147] It should be noted that, although in Figure 12 In the RRC IE, “frequencyDomainResources” and “frequencyDomainResourcesRepetition-r17” are bitmaps containing bits corresponding to each RB group within the BWP and have 45 bits, but this is not limited to any information indicating frequency domain resources.

[0148] (2.1.2) A second example of determining repetitive frequency domain resources

[0149] In the second determination example, terminal 10 determines multiple frequency domain resources for the CORESET based on frequency domain resource information and repetition count information contained in the CORESET information related to a single CORESET. The second configuration example will be described focusing on the differences from the first configuration example.

[0150] Figure 13This is a diagram illustrating a second determined example of frequency domain resources for repetition according to this embodiment. Figure 13 In this respect, the CORESET information for CORESET#1 includes repetition count information indicating the number of repetitions R (here, R = 3) for the PDCCH (but excludes multiple frequency domain resource information 1, 2 respectively indicating frequency domain resources #1 and #2 for CORESET#1). Figure 11 The difference.

[0151] like Figure 13 As shown, terminal 10 envisions continuously allocating frequency domain resources #0, #1, and #2 from frequency domain resource #0 to CORESET #1 with a repetition count R equal to the number of times R is repeated. Furthermore, terminal 10 envisions that the number of RBs in frequency domain resources #1 and #2 is equal to the number of RBs in frequency domain resource #0 (here, 6 RBs).

[0152] As described above, terminal 10 may also assume that search space #1 is configured for each of the frequency domain resources #0, #1, and #2 determined based on the RBs (more specifically, the location and number of RBs) and the number of repetitions R allocated to frequency domain resource #0 indicated by frequency domain resource information.

[0153] Figure 14 This is a diagram illustrating a second example of the CORESET information involved in this embodiment. For example, in Figure 14 In the RRC IE "ControlResourceSet" section, which contains CORESET information, the RRC IE "numRepetition-r17" indicating the number of repetitions R of PDCCH (or CORESET) (but not including...). Figure 12 The RRC IE "frequencyDomainResourcesRepetition-r17" can also be, for example... Figure 14 As shown, the number of repetitions R can be set to any of 1, 2, 4, 8, 16 or 32.

[0154] Thus, the CORESET information can include frequency domain resource information for the initial transmission (e.g., RRC IE "frequencyDomainResources"), as well as repetition count information (e.g., RRC IE "numRepetition-r17"). Figure 12 Compared to the frequency domain resource information shown after the second repetition, the second configuration example reduces the overhead caused by CORESET information compared to the first configuration example because the number of bits in the repetition count information is less.

[0155] (2.1.3) A third example of determining repetitive frequency domain resources

[0156] In the third determination example, terminal 10 determines multiple frequency domain resources for the CORESET based on frequency domain resource information and offset information contained in the CORESET information related to a single CORESET. The third configuration example is described focusing on the differences from the first or second configuration examples.

[0157] Figure 15 This is a diagram illustrating a second determined example of frequency domain resources for repetition according to this embodiment. Figure 15 In this respect, the CORESET information used for CORESET#1 includes offset information indicating the offsets used for frequency domain resources #1 and #2 respectively (but does not include repetition count information). Figure 13 different.

[0158] For example, in Figure 15 In the text, the offset information indicates the offset n of frequency domain resources #1 and #2 relative to the starting RB group of frequency domain resource #0. f1 and n f2 The offset value can also indicate the number of RB groups to be offset. Figure 15 In the middle, offset n f1 =2, causing frequency domain resource #1 to be offset by 2 RB groups from the starting RB group of frequency domain resource #0. Thus, the offset indicated by the offset value can be an integer multiple of the number of RBs constituting one RB group (e.g., 6 RBs), but is not limited to this, and can also be a predetermined number of RBs.

[0159] Terminal 10 assumes that the frequency domain resource information indicates frequency domain resource #0, and that the starting RB group of frequency domain resource #0 is offset by offset n. f1 n f2 The subsequent frequency domain resources #1 and #2 are allocated for CORESET #1. In addition, terminal 10 assumes that the number of RBs in frequency domain resources #1 and #2 is equal to the number of RBs in frequency domain resource #0 (6 RBs in this case).

[0160] In addition, although Figure 15 In the above, let the offset n used for frequency domain resource #i (i≥1) be... fi This is the offset relative to the starting RB group of frequency domain resource #0, but is not limited to this. The offset n of frequency domain resource #i (i≥1) fi It can also be an offset relative to the final RB group of frequency domain resource #0.

[0161] Additionally, the offset n of frequency domain resource #i (i≥1) fi It can also be the offset relative to the starting RB group of frequency domain resource #i-1. Or, the offset n of frequency domain resource #i (i≥1). fi It can also be the offset relative to the final RB group of frequency domain resource #i-1.

[0162] Figure 16 This is a diagram illustrating a third example of CORESET information related to this embodiment. For example, in Figure 16 In the context of CORESET information, the RRC IE "ControlResourceSet" can include the RRC IE "rbg-ShiftList-r17" indicating the offset of each frequency domain resource for subsequent repetitions (excluding...). Figure 12 The RRC IE "frequencyDomainResourcesRepetition-r17" indicates the offset of each frequency domain resource. The RRC IE "rbg-ShiftList-r17" is a list of RRC IEs "RBG-Shift-r17" indicating the offset of each frequency domain resource. For example, the RRC IE "RBG-Shift-r17" can specify offset values ​​from 1 to 32. The RRC IE "ControlResourceSet" can also contain the RRC IE "numRepetition-r17" indicating the number of repetitions R of the PDCCH.

[0163] Therefore, in addition to the frequency domain resource information used for the initial transmission (e.g., RRC IE "frequencyDomainResources"), the CORESET information may also include offset information indicating the offsets of each frequency domain resource used for subsequent repetitions (e.g., RRC IE "rbg-ShiftList-r17"). Figure 12 Compared to the frequency domain resource information shown after the second instance, the third configuration example reduces the overhead caused by CORESET information compared to the first configuration example because it uses fewer bits of offset information. Furthermore, since frequency domain resources #i can be distributed within the BWP, the frequency diversity gain is improved compared to the second configuration example.

[0164] Furthermore, although in the above, base station 20 is specified with an offset n for each frequency domain resource #i (0 < i < R) for the second and subsequent repetitions. fi However, this is not the only possibility. Base station 20 can also specify the common offset n of the frequency domain resources #i (0 < i < R) for subsequent repetitions. f The aforementioned CORESET information may also include an indication of the common offset n. f Offset information.

[0165] Figure 17 This is a diagram illustrating a fourth determined example of frequency domain resources for repetition according to this embodiment. Figure 17 In the frequency domain resource #i (0 < i < R) used for repetitions after the second iteration, a common offset n is used.f This point is consistent with Figure 15 Different. For example... Figure 17 As shown, the common offset n f It can also be the offset of frequency domain resource #i relative to the starting RB group of frequency domain resource #i-1 (i>0). Furthermore, although not illustrated, this common offset n... f It can also be the offset of the final RB group of frequency domain resource #i relative to frequency domain resource #i-1 (i>0).

[0166] like Figure 17 As shown, the CORESET information may also include offset information indicating the common offset of each frequency domain resource for subsequent repetitions and repetition information indicating the number of repetitions R of PDCCH (or CORESET). Terminal 10 assumes that the frequency domain resource information indicates frequency domain resource #0, and that the common offset n is offset from the starting RB group of frequency domain resource #0. f Frequency domain resource #1, and the common offset n from the starting RB group of frequency domain resource #1. f Frequency domain resource #2 is allocated for CORESET #1. Furthermore, terminal 10 assumes that the number of RBs in frequency domain resources #1 and #2 is equal to the number of RBs in frequency domain resource #0 (here, 6 RBs).

[0167] As described above, when the reuse search space is associated with a single CORESET, PDCCH can be repeated among multiple frequency domain resources by configuring multiple frequency domain resources for that single CORESET. In this case, by changing the CORESET information, PDCCH repetition among multiple frequency domain resources can be achieved even without changing the search space information.

[0168] (2.2) Reusable search space associated with multiple CORESETs

[0169] When a reuse search space is associated with multiple CORESETs, the multiple frequency domain resources for which the PDCCH is repeatedly transmitted can also correspond to each of those CORESETs. The search space information associated with this reuse search space can include the identification information of each of the multiple CORESETs.

[0170] Terminal 10 determines the frequency domain resources of each of the multiple CORESETs based on the CORESET information of each of the multiple CORESETs. Specifically, it determines the frequency domain resources of each CORESET within the multiple CORESETs based on the frequency domain resource information contained in the CORESET information.

[0171] Figure 18This is a diagram illustrating a fifth example of determining repetitive frequency domain resources according to this embodiment. For example, in Figure 18 In this context, assuming CORESET#1, #2, and #3 are associated with search space #1, which is used as a reuse search space, the CORESET information for each of CORESET#1, #2, and #3 contains frequency domain resource information indicating frequency domain resources #0, #1, and #2, respectively. The frequency domain resource information is as follows: Figure 11 As explained in the document.

[0172] like Figure 18 As shown, terminal 10 may also envision that search space #1 is configured in each of the frequency domain resources #0, #1, and #2 associated with CORESET #1, #2, and #3. Alternatively, terminal 10 may also envision using the frequency domain resources for CORESET #i (where i ≥ 1) to transmit the i-th repeated PDCCH and monitor the search space #1 associated with CORESET #i.

[0173] In addition, Figure 18 The CORESET periods of CORESETs #1, #2, and #3 associated with the reusable search space #1 are the same, but not limited to this; they can also be different. In this way, when multiple CORESETs are associated with the reusable search space #1, the CORESET period, frequency domain resources, etc., can be flexibly configured for each repetition.

[0174] Figure 19 This is a diagram illustrating an example of search space information involved in this embodiment. For example, Figure 19 An example is shown where the RRC IE “SearchSpace” as search space information contains identification information for multiple CORESETs associated with a reused search space.

[0175] For example, in Figure 19 In the RRC IE “SearchSpace” shown, the CORESET configured for monitoring the repeat search space for the first (1st) PDCCH can also be indicated by the RRC IE “controlResourceSetId”. On the other hand, the CORESET configured for monitoring the repeat search space for the second and subsequent PDCCHs can also be indicated by the RRC IE “controlResourceSetRepetition-r17”.

[0176] Thus, the search space information can include not only the identification information for the initial CORESET (e.g., RRCIE "controlResourceSetId"), but also a list of identification information for subsequent CORESETs (e.g., RRCIE "ControlResourceSetId") (e.g., RRCIE "controlResourceSetRepetition-r17"). The number of entries in this list can, for example, be equal to the repetition count R-1.

[0177] As described above, the CORESET information related to repeating CORESETs can be notified to the terminal 10 from the base station 20, distinct from the CORESET for the initial transmission. Specifically, the list of CORESET information can be included in information related to PDCCH (hereinafter referred to as "PDCCH information"). The PDCCH information can also include individual PDCCH information of the terminal 10 (hereinafter referred to as "individual PDCCH information") and / or more than one common PDCCH information of the terminal 10 (hereinafter referred to as "common PDCCH information").

[0178] Figure 20 This is a diagram illustrating an example of the PDCCH information involved in this embodiment. Figure 20 The example shown is an RRC IE “PDCCH-Config” as a separate PDCCH information and an RRC IE “PDCCH-ConfigCommon” as a common PDCCH information, which contains CORESET information and identification information for multiple CORESETs associated with the reuse search space.

[0179] For example, it could also be, Figure 20The shown RRC IE "PDCCH-Config" contains RRC IE "repetitionControlResourceSetToAddModList-r17", which is a list of RRC IE "ControlResourceSet". RRC IE "ControlResourceSet" is CORESET information configured as a repeat search space for monitoring PDCCHs after the second iteration. Alternatively, RRC IE "PDCCH-Config" may also contain RRC IE "repetitionControlResourceSetToReleaseList-r17", which is a list of RRC IE "ControlResourceSetId" serving as identification information for that CORESET. Furthermore, Figure 20 The RRC IE “PDCCH-ConfigCommon” shown can also include the aforementioned RRC IE “repetitionControlResourceSetToAddModList-r17”.

[0180] In this way, by including CORESET information of the CORESET configured with the search space reused in the individual PDCCH information and the public PDCCH information (e.g., RRC IE "repetitionControlResourceSetToAddModList-r17"), it is possible to use multiple CORESETs to repeatedly transmit both the individual PDCCH and one or more public PDCCHs of terminal 10 to terminal 10.

[0181] Thus, when the reuse search space is associated with multiple CORESETs, PDCCH can be repeated among multiple frequency domain resources by configuring multiple frequency domain resources corresponding to each CORESET. In this case, PDCCH repetition among multiple frequency domain resources can be achieved even without changing the CORESET information by changing the search space information and / or PDCCH information.

[0182] (3) Combination of first PDCCH monitoring and second PDCCH monitoring

[0183] In the first PDCCH monitoring described above, terminal 10 envisions monitoring the PDCCH that is repeatedly transmitted using the same frequency domain resources between different time domain resources (e.g., between time slots and / or between symbols within the same time slot), but is not limited thereto.

[0184] In the first PDCCH monitoring described above, terminal 10 can also control the monitoring of PDCCHs repeatedly transmitted using different frequency domain resources between different time domain resources (e.g., between time slots and / or between symbols within the same time slot). That is, the first PDCCH monitoring can be combined with the second PDCCH monitoring.

[0185] In addition, although in the second PDCCH monitoring described above, terminal 10 envisions monitoring of PDCCHs repeatedly transmitted between multiple frequency domain resources corresponding to more than one CORESET in the same time domain resource during a monitoring period of a predetermined period, it is not limited to this.

[0186] In the aforementioned second PDCCH monitoring, terminal 10 can also control the monitoring of PDCCHs repeatedly transmitted between multiple frequency domain resources corresponding to more than one CORESET in different time domain resources during a predetermined monitoring period. In other words, the second PDCCH monitoring can be combined with the first PDCCH monitoring.

[0187] Thus, the combination of first and second PDCCH monitoring, using different frequency domain resources to repeat PDCCH within each time domain resource in a predetermined monitoring period, can also be called "frequency hopping".

[0188] Figure 21 This diagram illustrates an example of repeated transmission of a frequency-hopping PDCCH according to this embodiment. For example, in Figure 21 As an example, it is shown in the text. Figure 2 The time slot repetition shown Figure 11 The combination shown is a first defined example of a combination of frequency domain resources used for repetition. Additionally, although not illustrated, it is of course possible to combine any aspects described in the first and second PDCCH monitoring.

[0189] like Figure 21 As shown, between the repeated monitoring time slots #0 and #1, different frequency domain resources #0 and #1 corresponding to CORESET #1 are used. Alternatively, terminal 10 envisions using frequency domain resource #0 to send the first PDCCH in monitoring time slot #0, and using frequency domain resource #1 to send the second PDCCH in monitoring time slot #1, to control the monitoring of search space #1.

[0190] In addition, Figure 21In this context, assuming that the number of repetitions R of the CORESET#1 configuration associated with search space#1 is repeated with PDCCH (e.g., in...), Figure 21 In this context, R=2) equal numbers of frequency domain resources #0 and #1, but not limited to these. The number N of frequency domain resources configured for this CORESET#1. FR It can be less than or greater than the number of repetitions R. When the number of repetitions R > the number of frequency domain resources N... FR In this case, the search space for repetition can also be configured in the same frequency domain resource for each predetermined number of repetitions. For example, frequency domain resource #0 can be used for the odd-numbered repetitions, and frequency domain resource #1 can be used for the even-numbered repetitions.

[0191] (4) Search space group switching control

[0192] Next, the switching control of search space groups will be explained. In this embodiment, the reused search space described in (1) to (3) above may be associated with more than one search space group. For example, the search space information (e.g., RRC IE “SearchSpace”) may also include search space group information (e.g., RRC IE “searchSpaceGroupIdList”) indicating more than one search space group associated with the reused search space.

[0193] Terminal 10 controls the switching of search space groups based on the values ​​of predetermined fields in the DCI. Figure 22 This diagram illustrates an example of the switching of search space groups involved in this embodiment. Figure 22 The image shows an example of terminal 10 switching the search space group used for monitoring repeatedly transmitted PDCCHs from search space group #1 to #2.

[0194] For example, in Figure 22 In this context, the monitoring period k2 for the reused search space associated with search space group #2 is longer than the monitoring period k1 for the reused search space associated with search space group #1. Furthermore, in... Figure 22 It is assumed that the monitoring periods T1 and T2 of the search spaces associated with search space groups #1 and #2 are the same, but it is not limited to this. The structure of the search space associated with each search space group (e.g., monitoring period k, monitoring period T, the start time slot of monitoring period T, the number of PDCCH candidates for each aggregation level, the symbols configured in the monitoring time slot, etc.) can be freely set according to the search space information used for that search space.

[0195] exist Figure 22In this process, terminal 10 controls the switching of search space groups based on the values ​​of predetermined fields within the DCI. Additionally, terminal 10 controls the monitoring of PDCCHs using reused search spaces associated with that search space group based on the values ​​of the predetermined fields within the DCI.

[0196] Figure 23 This diagram illustrates an example of a DCI used for switching control of search space groups according to this embodiment. Figure 23 As shown, the DCI can also be a DCI format for downlink shared channel scheduling (e.g., DCI format 1_X) or a DCI format for uplink shared channel scheduling (e.g., DCI format 0_X). Here, X is any integer.

[0197] The following description uses downlink shared channel (PDSCH) and uplink shared channel (PUSCH) as examples of downlink shared channel and uplink shared channel. However, the names of downlink shared channel and uplink shared channel are not limited to PDSCH and PUSCH as long as they are used to transmit user data and / or higher layer parameters.

[0198] like Figure 23 As shown, DCI format 1_X or 0_X may also include a search space group switching field for switching search space groups, and a resource allocation field indicating the resources allocated to PDSCH or PUSCH, etc.

[0199] Or, such as Figure 23 As shown, the DCI described above can also be a DCI format other than PDSCH or PUSCH for scheduling (e.g., DCI format 2_X). Here, X is any integer. Figure 23 As shown, DCI format 2_X can contain M (M≥1) search space group switching fields #1 to #M. Here, M can be, for example, the number of cells C configured in terminal 10. Furthermore, DCI format 2_X is not limited to what is shown; it can also contain a single search space group switching field.

[0200] Figure 24 This is a diagram illustrating an example of the value of the search group switching field according to this embodiment. Furthermore, Figure 23 and Figure 24 The search group switching field in the DCI can be a predefined field, and its name is not limited to this. Additionally, although in Figure 24 The assumption here is that the search group switching field is 2 characters, but it is not limited to this; as long as it is 1 character or more, it is acceptable.

[0201] like Figure 24 As shown, the values ​​in the search group toggle field can also indicate the search space group of the toggle target. Figure 24 The assumption is that the search space group of the switching target indicated by the values ​​of the search group switching field is configured to the terminal 10 by higher-level parameters, but it is not limited to this and can also be specified in advance in the specification.

[0202] Additionally, for terminal 10, the value of the search group switching field can also indicate information related to the number of times R of PDCCH being monitored in the search space associated with the search space group indicated by that value. For example, in Figure 24 In this context, the information related to the number of repetitions R is parameter values ​​r1 to r4, but is not limited to these; it can also be the number of repetitions R itself. Terminal 10 can also receive information indicating the maximum value rep_max of the number of repetitions R, separately from the DCI.

[0203] like Figure 24 As shown, terminal 10 can also determine the number of repetitions R using the maximum value rep_max and the parameter value indicated by the value of the search group switching field mentioned above. Furthermore, Figure 24 This is just an example; of course, the number of repetitions R associated with each value of the search group switching field can be specified in the specification.

[0204] Additionally, in scheduling where the DCI format used (e.g., DCI format 1_X or 0_X) is PDSCH or PUSCH, including the search group switching field, terminal 10 can also determine the number of repetitions R of PDSCH or PUSCH based on the value of the search group switching field. Thus, according to Figure 23 The repetition count R derived from the search space group switching field value of DCI format 1_X or 0_X can also be the repetition count R of PDSCH or PUSCH. Note that the repetition count R of PDSCH or PUSCH can be derived in the same way as the repetition count R of PDCCH mentioned above.

[0205] Additionally, the DCI format used in the scheduling of PDSCH or PUSCH (e.g., DCI format 1_X or 0_X) can also be included separately from the value of the search group switching field mentioned above in the predetermined field value used in deriving the repetition count R of PDSCH or PUSCH. In this case, terminal 10 can also determine the repetition count R of PDCCH based on the value of the search space group switching field, and determine the repetition count R of PDSCH or PUSCH based on the predetermined field value.

[0206] Additionally, in terminal 10, the value of the search space group switching field in a DCI format other than the aforementioned PDSCH or PUSCH scheduling (e.g., DCI format 2_X) can also be used to derive the repetition count R of PDSCH and / or PUSCH. Alternatively, the value of the search space group switching field in this DCI format can be used to derive the repetition count R of PDCCH, while other field values ​​in this DCI format can be used to derive the repetition count R of PDSCH or PUSCH.

[0207] As described above, when dynamically switching search space groups using DCI, the repetition count R of the PDCCH monitored in the search space associated with that search space group can be dynamically controlled. Therefore, the monitoring of the PDCCH can be appropriately controlled. Furthermore, the repetition count of the PDSCH or PUSCH scheduled through the DCI can also be dynamically controlled.

[0208] (Structure of a wireless communication system)

[0209] Next, the structure of each device in the wireless communication system 1 described above will be explained. Furthermore, the following structures are used to illustrate structures necessary for the description of this embodiment and do not exclude the possibility that each device may have functional blocks other than those shown in the figures.

[0210] <Hardware Structure>

[0211] Figure 25 This diagram illustrates an example of the hardware structure of each device within the wireless communication system according to this embodiment. Each device within the wireless communication system 1 (e.g., terminal 10, base station 20, CN 30, etc.) includes a processor 11, a storage device 12, a communication device 13 for wired or wireless communication, and an input / output device 14 for receiving various input operations and outputting various information.

[0212] The processor 11, for example, is a central processing unit (CPU) that controls the various devices within the wireless communication system 1. The processor 11 can also perform the various processes described in this embodiment by reading and executing programs from the storage device 12. Each device within the wireless communication system 1 can be composed of one or more processors 11. Alternatively, these devices can also be referred to as computers.

[0213] Storage device 12 may be composed of storage devices such as memory, hard disk drive (HDD), and / or solid state drive (SSD). Storage device 12 may store various information required by processor 11 to perform processing (e.g., programs executed by processor 11).

[0214] The communication device 13 is a device that communicates via wired and / or wireless networks, and may include, for example, a network interface card (NIC), a communication module, a chip, an antenna, etc. Additionally, the communication device 13 may also include an amplifier, a radio frequency (RF) device for processing wireless signals, and a baseband (BB) device for processing baseband signals.

[0215] An RF device, for example, generates a wireless signal to be transmitted from antenna A by performing D / A conversion, modulation, frequency conversion, and power amplification on the digital baseband signal received from antenna A. Additionally, the RF device generates a digital baseband signal and transmits it to antenna A by performing frequency conversion, demodulation, and A / D conversion on the wireless signal received from antenna A. Antenna A performs the processes of converting the digital baseband signal into packets and converting packets back into digital baseband signals.

[0216] Input / output device 14 includes input devices such as a keyboard, touch panel, mouse and / or microphone, and output devices such as a display and / or speaker.

[0217] The hardware structure described above is just one example. The various devices within the wireless communication system 1 can be omitted. Figure 25 Part of the hardware described in the document can also have Figure 25 Hardware not documented in the document. Furthermore... Figure 4 The hardware shown can consist of one or more chips.

[0218] <Functional Block Structure>

[0219] "terminal"

[0220] Figure 26 This is a diagram illustrating an example of the functional block structure of the terminal according to this embodiment. Figure 26 As shown, the terminal 10 includes a receiving unit 101, a transmitting unit 102, and a control unit 103.

[0221] Furthermore, all or part of the functions implemented by the receiving unit 101 and the transmitting unit 102 can be implemented using the communication device 13. Additionally, all or part of the functions implemented by the receiving unit 101 and the transmitting unit 102, as well as the control unit 103, can be implemented by the processor 11 executing a program stored in the storage device 12. Furthermore, this program can be stored in a storage medium. The storage medium storing the program can also be a non-transitory computer-readable medium. There are no particular limitations on the non-transitory storage medium; it can be a storage medium such as a USB flash drive or a CD-ROM.

[0222] The receiving unit 101 receives downlink signals. Additionally, the receiving unit 101 may also receive information and / or data transmitted via downlink signals. Here, "receiving" may include performing at least one reception-related process, such as receiving, demapping, demodulating, decoding, monitoring, or measuring wireless signals.

[0223] Downlink signals may also include at least one of the following: the aforementioned PDCCH, PDSCH, downlink reference signal, synchronization signal, broadcast channel, etc. Downlink reference signals may also include, for example, the demodulation reference signal (DMRS) of the PDCCH or PDSCH.

[0224] Additionally, receiving unit 101 receives DCI. Specifically, receiving unit 101 can detect PDCCH by monitoring the search space and receive DCI transmitted via PDCCH. Receiving unit 101 can receive PDSCH based on DCI, and receive user data and / or higher-layer parameters transmitted via PDSCH. Furthermore, receiving unit 101 can send DCI containing values ​​of predetermined fields used in the switching of search space groups (e.g., Figure 23 ).

[0225] The receiving unit 101 can receive search space information related to the search space associated with the control resource set (CORESET) (e.g., Figure 9 , 19 Additionally, the receiving unit 101 can receive CORESET information related to one or more CORESETs associated with the search space (e.g., Figure 12 , 14 16).

[0226] In addition, the receiving unit 101 can receive the aforementioned PDCCH information (e.g., Figure 20 The PDCCH information may differ in each predetermined bandwidth (e.g., BWP or cell C) configured in terminal 10, and may also include CORESET information related to more than one CORESET used within that predetermined bandwidth, and search space information related to more than one search space.

[0227] Additionally, the receiving unit 101 can receive information indicating the maximum value of the repetition count R (e.g., Figure 24 This information can be included in the search space information mentioned above.

[0228] Alternatively, the receiving unit 101 can combine the repeatedly transmitted PDCCHs and decode the DCI based on the combined result. Or, the receiving unit 101 can decode the DCI based on each PDCCH instead of combining the repeatedly transmitted PDCCHs.

[0229] The transmitting unit 102 transmits an uplink signal. Additionally, the transmitting unit 102 may also transmit information and / or data transmitted via the uplink signal. Here, "transmission" may include performing at least one transmission-related process, such as encoding, modulation, mapping, or transmission of wireless signals. The uplink signal may, for example, include at least one of the above-described PUSCH, uplink reference signal, etc. The uplink reference signal may, for example, include the DMRS of the PUSCH, etc.

[0230] The control unit 103 performs various controls within the terminal 10. Specifically, the control unit 103 can control the monitoring of the downlink control channel of the search space during a predetermined monitoring period T based on the aforementioned search space information and / or the aforementioned CORESET information.

[0231] The control unit 103 can control the monitoring of PDCCHs that are repeatedly transmitted between different time slots and / or within the same time slot during the monitoring period T based on the repetition information related to the repetition of PDCCHs contained in the search space information (see (1) above).

[0232] Here, the aforementioned repetition information may include information indicating the number of repetitions R of the PDCCH. The control unit 103 can determine the different time slots mentioned above (e.g., based on this number of repetitions R). Figures 4 to 6 , Figure 8 , Figure 9 ).

[0233] Additionally, the aforementioned repetition information may include information indicating the maximum value of the repetition count R of the PDCCH. The control unit 103 can determine the different time slots mentioned above (e.g., based on this maximum value and the repetition count R determined within the DCI). Figures 4 to 6 , Figure 8 and Figure 10 ).

[0234] Additionally, the aforementioned repetition information may include information indicating the start time slot #k0 of PDCCH repetition. The control unit 103 can determine the different time slots based on the start time slot #k0 (e.g., Figures 4 to 8 ).

[0235] Furthermore, the aforementioned different time slots can be multiple time slots within a single monitoring period T within a predetermined period (e.g., Figure 4 Alternatively, it could be multiple time slots across multiple periods in a predetermined monitoring period T (e.g., Figure 5 , Figure 6 and Figure 8 ).

[0236] Furthermore, the aforementioned repetition information may include repetition symbol information indicating that the PDCCH is being repeated. The control unit 103 can determine, based on the repetition symbol information and the monitoring symbol information indicating the monitoring of the PDCCH, multiple symbols monitoring the PDCCH within the same time slot (e.g., Figure 7 and Figure 8 ).

[0237] The control unit 103 can control the monitoring of PDCCHs repeatedly transmitted using the same frequency domain resources between different time slots and / or within the same time slot (see (1) above). Furthermore, the control unit 103 can control the monitoring of PDCCHs repeatedly transmitted using different frequency domain resources in different time slots and / or within the same time slot (see (3) above, for example...). Figure 21 ).

[0238] The control unit 103 can control the monitoring of PDCCHs that are repeatedly transmitted between multiple frequency domain resources corresponding to one or more CORESETs (see (2) above).

[0239] Alternatively, the search space can be associated with a single CORESET, with the aforementioned multiple frequency domain resources corresponding to that single CORESET (see (2.1) above).

[0240] The CORESET information for a single CORESET may include multiple frequency domain resource information that respectively indicate the multiple frequency domain resources. The control unit 103 may determine the multiple frequency domain resources (e.g., based on the multiple frequency domain resource information) Figure 11 and Figure 12 ).

[0241] Additionally, the CORESET information for this single CORESET may include frequency domain resource information indicating one of the aforementioned frequency domain resources, and repetition count information indicating the repetition count R of the PDCCH. The control unit 103 may also determine the aforementioned multiple frequency domain resources (e.g., based on the frequency domain resource information and the repetition count information) Figure 13 and Figure 14 ).

[0242] Additionally, the CORESET information for this single CORESET may include frequency domain resource information indicating one of the plurality of frequency domain resources, and offset information indicating the offsets used by the other frequency domain resources among the plurality of frequency domain resources. The control unit 103 may determine the plurality of frequency domain resources (e.g., based on the frequency domain resource information and the offset information) Figures 15 to 17 ).

[0243] Alternatively, the search space may be associated with multiple CORESETs, with the aforementioned multiple frequency domain resources corresponding to each of the multiple CORESETs (see (2.2) above).

[0244] The control unit 103 can also determine the aforementioned multiple frequency domain resources (e.g., based on multiple CORESET information related to the multiple CORESETs respectively) Figures 18 to 20 ).

[0245] The control unit 103 can also determine the monitoring period T for a predetermined period of time during which the search space is used to monitor the PDCCH based on the search space information described above. Additionally, the control unit 103 can also determine the multiple frequency domain resources corresponding to the same time domain resource within the monitoring period T (see (2) above). Alternatively, it can determine multiple frequency domain resources corresponding to different time domain resources within the monitoring period T (see (3) above, for example, Figure 21 ).

[0246] Furthermore, if the receiving unit 101 successfully decodes the (i+1)th (0≤i<R-1)th PDCCH, the control unit 103 can suspend monitoring of PDCCHs after the (i+2)th. For example, after successfully decoding time slot #k... i In the case of the (i+1)th PDCCH, the control unit 103 can abort at time slot #k. i+1 The monitoring of the reuse search space set after frequency resource #i can be stopped, or the monitoring of the number of repetitions R can continue. Similarly, if the (i+1)th PDCCH in frequency resource #i is successfully decoded, the control unit 103 can stop the monitoring of the reuse search space set after frequency resource #i+1, or it can continue the monitoring of the number of repetitions R.

[0247] In addition, the control unit 103 can control the switching of search space groups based on the value of a predetermined field within the DCI. The control unit 103 can determine the number of times R of the PDCCH monitored using the search space associated with the search space group based on the value of the predetermined field (see (4) above).

[0248] Additionally, the control unit 103 can determine the number of repetitions R of the PDCCH monitored using the search space associated with the switched search space group based on the maximum value of the PDCCH repetition count R and a predetermined field value within the DCI (e.g., Figure 24 ).

[0249] In addition, when the switching of search space groups is controlled based on the value of a predetermined field in the DCI, the control unit 103 can determine the number of repetitions of the PDSCH or PUSCH scheduled through the DCI.

[0250] Base Station

[0251] Figure 27 This diagram illustrates an example of the functional block structure of a base station according to this embodiment. Figure 27 As shown, the base station 20 includes a receiving unit 201, a transmitting unit 202, and a control unit 203.

[0252] Furthermore, all or part of the functions implemented by the receiving unit 201 and the transmitting unit 202 can be implemented using the communication device 13. Additionally, all or part of the functions implemented by the receiving unit 201 and the transmitting unit 202, as well as the control unit 203, can be implemented by the processor 11 executing a program stored in the storage device 12. Furthermore, this program can be stored in a storage medium. The storage medium storing the program can also be a computer-readable, non-transient storage medium. There are no particular limitations on the non-transient storage medium; it can be a storage medium such as a USB flash drive or a CD-ROM.

[0253] The receiving unit 201 receives the aforementioned uplink signal. Additionally, the receiving unit 201 can also receive information and / or data transmitted via the aforementioned uplink signal.

[0254] The transmitting unit 202 transmits the aforementioned downlink signal. Additionally, the transmitting unit 202 may also transmit information and / or data transmitted via the aforementioned downlink signal.

[0255] In addition, the transmitting unit 202 transmits the DCI. Specifically, the transmitting unit 202 can transmit the DCI via the PDCCH. The transmitting unit 202 can also transmit the PDSCH that is scheduled via the DCI.

[0256] Additionally, the sending unit 202 can send DCI containing the values ​​of predetermined fields used in the switching of search space groups (e.g., Figure 23 The value of this predetermined field can also indicate information related to the number of repetitions of the downlink control channel monitored using the search space associated with the search space group. The value of this predetermined field can also indicate information related to the number of repetitions of the downlink shared channel or uplink shared channel scheduled via the downlink control information.

[0257] The sending unit 202 can send search space information related to the search space associated with the control resource set (CORESET) (e.g., Figure 9 , Figure 19 Additionally, the receiving unit 101 can send CORESET information related to one or more CORESETs associated with the search space (e.g., Figure 12 , 14 16). Additionally, the transmitting unit 202 can also transmit the aforementioned PDCCH information (e.g., Figure 20Additionally, the transmitting unit 202 may also transmit information indicating the maximum value of the repetition count R (e.g., Figure 24 ).

[0258] The control unit 203 performs various controls within the base station 20. Specifically, the control unit 203 can control the transmission of the downlink control channel within the search space during a predetermined monitoring period T, based on the aforementioned search space information and / or the aforementioned CORESET information.

[0259] The controller 203 can control the repeated transmission of PDCCH between different time slots and / or within the same time slot during the monitoring period T based on the repetition information related to the repetition of PDCCH contained in the search space information (see (1) above).

[0260] Here, the aforementioned repetition information may include information indicating the number of repetitions R of the PDCCH. The control unit 203 can determine the different time slots mentioned above based on this number of repetitions R (e.g., Figures 4 to 6 and Figure 9 ).

[0261] Additionally, the aforementioned repetition information may include information indicating the maximum value of the repetition count R of the PDCCH. The control unit 203 can determine the different time slots (e.g., based on this maximum value and the repetition count R determined within the DCI). Figures 4 to 6 and Figure 10 ).

[0262] Additionally, the aforementioned repetition information may also include information indicating the start time slot #k0 for PDCCH repetition. The control unit 203 may also determine the different time slots based on the start time slot #k0 (e.g., Figures 4 to 8 ).

[0263] Furthermore, the aforementioned different time slots can be multiple time slots within a single monitoring period T within a predetermined period (e.g., Figure 4 Alternatively, it could be multiple time slots across multiple periods in a predetermined monitoring period T (e.g., Figure 5 and Figure 6 ).

[0264] Furthermore, the aforementioned duplication information may include duplication symbol information indicating that the PDCCH is being repeated. The control unit 203 can determine, based on the duplication symbol information and the monitoring symbol information indicating the monitoring of the PDCCH, multiple symbols that repeatedly transmit the PDCCH within the same time slot (e.g., Figure 7 and Figure 8 ).

[0265] The control unit 203 can control the repeated transmission of PDCCHs using the same frequency domain resources between different time slots and / or within the same time slot (see (1) above). Furthermore, the control unit 203 can control the repeated transmission of PDCCHs using different frequency domain resources in different time slots and / or within the same time slot (see (3) above).

[0266] The control unit 203 can control the repeated transmission of PDCCH between multiple frequency domain resources corresponding to one or more CORESETs (see (2) above).

[0267] Alternatively, the search space can be associated with a single CORESET, with the aforementioned multiple frequency domain resources corresponding to that single CORESET (see (2.1) above).

[0268] The CORESET information for a single CORESET may include multiple frequency domain resource information that respectively indicate the multiple frequency domain resources. The control unit 203 may determine the multiple frequency domain resources (e.g., based on the multiple frequency domain resource information) Figure 11 and Figure 12 ).

[0269] Additionally, the CORESET information for this single CORESET may include frequency domain resource information indicating one of the aforementioned frequency domain resources, and repetition count information indicating the repetition count R of the PDCCH. The control unit 203 can determine the aforementioned multiple frequency domain resources (e.g., based on the frequency domain resource information and the repetition count information) Figure 13 and Figure 14 ).

[0270] Additionally, the CORESET information for this single CORESET may include frequency domain resource information indicating one of the plurality of frequency domain resources, and offset information indicating the offsets used by the other frequency domain resources among the plurality of frequency domain resources. The control unit 203 can determine the plurality of frequency domain resources (e.g., based on the frequency domain resource information and the offset information) Figures 15 to 17 ).

[0271] Alternatively, the search space may be associated with multiple CORESETs, with the aforementioned multiple frequency domain resources corresponding to each of the multiple CORESETs (see (2.2) above).

[0272] Control unit 203 can determine the aforementioned multiple frequency domain resources (e.g., based on multiple CORESET information related to the multiple CORESETs respectively) Figures 18 to 20 ).

[0273] The control unit 203 can determine the monitoring period T for a predetermined period of repeatedly transmitting the PDCCH using the search space based on the search space information described above. Additionally, the control unit 203 can also determine the multiple frequency domain resources corresponding to the same time domain resource within the monitoring period T (see (1) above). Alternatively, it can determine multiple frequency domain resources corresponding to different time domain resources within the monitoring period T (see (3) above).

[0274] In addition, the control unit 203 can also control the switching of search space groups (see (4) above).

[0275] (Operation of a wireless communication system)

[0276] Next, the operation of the wireless communication system 1 constructed as described above will be explained. Note that... Figure 28 and Figure 29 This is merely an example; of course, some steps can be omitted, or steps not shown can be implemented.

[0277] Figure 28 This diagram illustrates an example of PDCCH monitoring operation in a wireless communication system according to this embodiment. Figure 28 As shown, in step S101, terminal 10 receives more than one search space information and / or more than one CORESET information. For example, the search space information and / or the CORESET information may be included in an RRC reconfiguration message, but are not limited thereto.

[0278] In step S102, the terminal 10 configures a search space for monitoring repeatedly transmitted PDCCHs during a predetermined monitoring period T based on the search space information and / or the CORESET information.

[0279] In step S103, terminal 10 uses the search space configured in step S102 to monitor PDCCHs that are repeatedly transmitted using different time domain resources and / or different frequency domain resources (see (1) to (3) above).

[0280] As described above, the wireless communication system 1 according to this embodiment can appropriately control the monitoring of PDCCHs that are repeatedly transmitted using different time-domain resources and / or different frequency-domain resources.

[0281] Figure 29 This diagram illustrates an example of a search space group switching operation in a wireless communication system according to this embodiment. Figure 29 As shown, in step S201, terminal 10 receives DCI.

[0282] In step S202, terminal 10 controls the switching of the search space group based on the value of a predetermined field within the DCI received in step S201. Specifically, terminal 10 can switch the search space group used for monitoring the PDCCH to the search space group indicated by the value of the predetermined field.

[0283] In step S203, terminal 10 can determine the number of times R of the PDCCH being monitored in the search space associated with the search space group of the handover target in step S202, based on the value of a predetermined field in the DCI received in step S201.

[0284] In step S204, terminal 10 uses the search space to monitor PDCCHs that are repeatedly sent according to the number of repetitions R determined in step S203 (see (1) to (3) above).

[0285] (Other implementation methods)

[0286] The various signals, information, and parameters described above can be transmitted at any layer. That is, the various signals, information, and parameters described above can be replaced with signals, information, and parameters from any layer, such as higher layers (e.g., Non-Access (NAS) layer, RRC layer, MAC layer, etc.) and lower layers (e.g., physical layer). In addition, the notification of predetermined information is not limited to explicit notification, but can also be implicit (e.g., by not notifying information or using other information).

[0287] Furthermore, the names of various signals, information, parameters, IE, channels, time units, and frequency units in the above embodiments are merely exemplary and can be replaced with other names. For example, a time slot can be any name as long as it is a time unit with a predetermined number of symbols. Similarly, an RB can be any name as long as it is a frequency unit with a predetermined number of subcarriers.

[0288] Furthermore, the purpose of the terminal 10 in the above embodiments (e.g., RedCap, IoT-oriented, etc.) is not limited to the exemplified purposes. As long as it has the same function, it can be used for any purpose (e.g., eMBB, URLLC, Device-to-Device (D2D), Vehicle-to-Everything (V2X), etc.). Additionally, the form of various information is not limited to the above embodiments and can be appropriately changed to bit representations (0 or 1), Boolean values ​​(Boolean: true or false), integer values, characters, etc. Furthermore, the singular and plural forms in the above embodiments can also be interchanged.

[0289] The embodiments described above are for the purpose of facilitating understanding of this disclosure and are not intended to limit its interpretation. The flowcharts, timing sequences, elements and their configurations, indexes, conditions, etc., described in the embodiments are not limited to those illustrated and can be appropriately modified. Furthermore, at least some of the structures described in the above embodiments can be partially replaced or combined.

Claims

1. A terminal, comprising: The control unit monitors the physical downlink control channels in multiple search spaces configured in the time domain. as well as The receiving unit receives a Radio Resource Control (RRC) reconfiguration message, which includes information indicating the symbols for monitoring the Physical Downlink Control Channel (PLC) within a time slot, information for identifying multiple search spaces repeatedly executed for the PLC, and information indicating the period and offset of the time slots for monitoring the PLC. The control unit determines the symbols to be monitored for the repeated physical downlink control channel based on information indicating the symbols to be monitored in the time slot, information for identifying multiple search spaces for repeated execution of the physical downlink control channel, and information indicating the period and offset of the time slot for monitoring the physical downlink control channel.

2. The terminal according to claim 1, Information indicating the symbols of the physical downlink control channel being monitored within the time slot, information for identifying multiple search spaces repeatedly executed for the physical downlink control channel, and information indicating the period and offset of the time slot for monitoring the physical downlink control channel are configured for one or more bandwidth portions (BWPs), respectively.

3. A base station, comprising: The control unit controls the transmission of physical downlink control channels in multiple search spaces configured in the time domain; as well as The transmitting unit transmits a Radio Resource Control (RRC) reconfiguration message, which includes information indicating the symbols for monitoring the Physical Downlink Control Channel (PLC) within a time slot, information for identifying multiple search spaces repeatedly executed for the PLC, and information indicating the period and offset of the time slot for determining the monitoring of the PLC. The control unit controls the transmission of the repeated physical downlink control channel based on information indicating the symbols of the physical downlink control channel monitored within the time slot, information for identifying multiple search spaces for repeated execution of the physical downlink control channel, and information indicating the period and offset of the time slot for determining the monitoring of the physical downlink control channel.

4. A wireless communication method for a terminal, comprising: The steps for controlling the monitoring of physical downlink control channels in multiple search spaces configured in the time domain; as well as The step of receiving a Radio Resource Control (RRC) reconfiguration message, wherein the RRC reconfiguration message includes information indicating the symbols for monitoring the Physical Downlink Control Channel within a time slot, information for identifying multiple search spaces repeatedly executed for the Physical Downlink Control Channel, and information indicating the period and offset of the time slot for determining the monitoring of the Physical Downlink Control Channel. In the control step, the symbols for monitoring the repeated physical downlink control channel are determined based on information indicating the symbols for monitoring the physical downlink control channel within the time slot, information for identifying multiple search spaces for repeated execution of the physical downlink control channel, and information indicating the period and offset of the time slot for determining the monitoring of the physical downlink control channel.

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