WO2022154067A1

WO2022154067A1 - Terminal, base station, and wireless communication method

Info

Publication number: WO2022154067A1
Application number: PCT/JP2022/001017
Authority: WO
Inventors: 秀明 ▲高▼橋; 治彦曽我部
Original assignee: 株式会社デンソー
Priority date: 2021-01-14
Filing date: 2022-01-14
Publication date: 2022-07-21
Also published as: JP2022108899A

Abstract

This terminal comprises: a receiving unit for receiving control resource set information pertaining to one or more control resource sets associated with a search space; and a control unit for controlling, on the basis of the control resource set information, monitoring of a downlink control channel using the search space, wherein the control unit controls monitoring of the downlink control channel, which is repeatedly transmitted between a plurality of frequency domain resources corresponding to the one or more control resource sets.

Description

Terminals, base stations and wireless communication methods

Cross-reference of related applications

This application is based on Japanese Patent Application No. 2021-004110 filed on January 14, 2021 and asserts the benefit of its priority. Incorporated herein by reference.

This disclosure relates to terminals, base stations and wireless communication methods.

In the Third Generation Partnership Project (3GPP), which is an international standardization organization, Long Term Evolution (LTE), which is the 3.9th generation wireless access technology (RAT), and LTE-Advanced, which is the 4th generation RAT, As a successor, Release 15 of New Radio (NR), which is a 5th generation (Fifth Generation: 5G) RAT, is specified (for example, Non-Patent Document 1).

In Release 15, by providing a control resource set (CORESET) in at least a part of the bandwidth available to the terminal (for example, User Equipment (UE)), the entire bandwidth available to the terminal is covered. The frequency utilization efficiency is improved as compared with LTE in which a control area is provided.

Currently, 3GPP has begun studying functions assuming terminals for the Internet of Things (IoT) that perform wireless access using NR. Regarding the terminal for the IoT, it is expected that the available bandwidth will be narrower than that of the terminal introduced in Release 15. In order to compensate for the decrease in coverage caused by such a narrow bandwidth, repeated transmission of downlink control channels is also being considered.

One of the purposes of the present disclosure is to provide terminals, base stations and wireless communication methods capable of appropriately controlling the monitoring of downlink control channels transmitted repeatedly.

The terminal according to one aspect of the present disclosure includes a receiving unit that receives control resource set information related to one or more control resource sets associated with the search space, and downlink control using the search space based on the control resource set information. A control unit that controls monitoring of the channel is provided, and the control unit controls monitoring of the downlink control channel that is repeatedly transmitted between a plurality of frequency domain resources corresponding to the one or more control resource sets. You may.

According to one aspect of the present disclosure, it is possible to appropriately control the monitoring of the downlink control channel that is repeatedly transmitted.

FIG. 1 is a diagram showing an example of an outline of a wireless communication system according to the present embodiment. FIG. 2 is a diagram showing an example of PDCCH monitoring in NR. FIG. 3 is a diagram showing another example of PDCCH monitoring in NR. FIG. 4 is a diagram showing a first example of inter-slot repetition according to the present embodiment. FIG. 5 is a diagram showing a second example of inter-slot repetition according to the present embodiment. FIG. 6 is a diagram showing a third example of inter-slot repetition according to the present embodiment. FIG. 7 is a diagram showing a first example of in-slot repetition according to the present embodiment. FIG. 8 is a diagram showing an example of a combination of inter-slot repetition and intra-slot repetition according to the present embodiment. FIG. 9 is a diagram showing an example of search space information according to the present embodiment. FIG. 10 is a diagram showing an example of deriving the number of repetitions according to the present embodiment. FIG. 11 is a diagram showing a first determination example of the frequency domain resource for repetition according to the present embodiment. FIG. 12 is a diagram showing a first example of CORESET information according to the present embodiment. FIG. 13 is a diagram showing a second determination example of the frequency domain resource for repetition according to the present embodiment. FIG. 14 is a diagram showing a second example of CORESET information according to the present embodiment. FIG. 15 is a diagram showing a second determination example of the frequency domain resource for repetition according to the present embodiment. FIG. 16 is a diagram showing a third example of CORESET information according to the present embodiment. FIG. 17 is a diagram showing a fourth determination example of the frequency domain resource for repetition according to the present embodiment. FIG. 18 is a diagram showing a fifth determination example of the frequency domain resource for repetition according to the present embodiment. FIG. 19 is a diagram showing an example of search space information according to the present embodiment. FIG. 20 is a diagram showing an example of PDCCH information according to the present embodiment. FIG. 21 is a diagram showing an example of repeated transmission of PDCCH to which frequency hopping according to the present embodiment is applied. FIG. 22 is a diagram showing an example of switching the search space group according to the present embodiment. FIG. 23 is a diagram showing an example of DCI used for switching control of the search space group according to the present embodiment. FIG. 24 is a diagram showing an example of the value of the search group switching field according to the present embodiment. FIG. 25 is a diagram showing an example of the hardware configuration of each device in the wireless communication system according to the present embodiment. FIG. 26 is a diagram showing an example of the functional block configuration of the terminal according to the present embodiment. FIG. 27 is a diagram showing an example of the functional block configuration of the base station according to the present embodiment. FIG. 28 is a diagram showing an example of the operation of PDCCH monitoring in the wireless communication system according to the present embodiment. FIG. 29 is a diagram showing an example of the operation of switching the search space group in the wireless communication system according to the present embodiment.

An embodiment of the present disclosure will be described with reference to the accompanying drawings. In each figure, those having the same reference numerals may have the same or similar configurations.

FIG. 1 is a diagram showing an example of an outline of a wireless communication system according to the present embodiment. As shown in FIG. 1, the wireless communication system 1 may include a terminal 10, a base station 20, and a core network 30. The numbers of terminals 10 and base stations 20 shown in FIG. 1 are merely examples, and are not limited to the numbers shown.

As the wireless access technology (RadioAccess Technology: RAT) of the wireless communication system 1, for example, NR is assumed, but the present invention is not limited to this, and various RATs such as 6th generation or later RATs can be used.

The terminal 10 is a predetermined terminal or device such as a smartphone, a personal computer, an in-vehicle terminal, an in-vehicle device, a stationary device, a telematics control unit (TCU), or the like. The terminal 10 may be called a user device (User Equipment: UE), a mobile station (Mobile Station: MS), a terminal (User Terminal), a wireless device (Radio apparatus), a subscriber terminal, an access terminal, or the like. The terminal 10 may be a mobile type or a fixed type. The terminal 10 is configured to be communicable using, for example, NR as a RAT.

The base station 20 forms one or more cells C and communicates with the terminal 10 using the cells C. The cell C may be paraphrased as a serving cell, a carrier, a component carrier (CC), or the like. The base station 20 includes gNodeB (gNB), en-gNB, Next Generation-Radio Access Network (NG-RAN) node, low power node (low-power node), Central Unit (CU), Distributed Unit (DU), and gNB. -DU, Remote Radio Head (RRH), Integrated Access and Backhaul / Backhauling (IAB) node, etc. may be called. The base station 20 is not limited to one node, and may be composed of a plurality of nodes (for example, a combination of a lower node such as DU and an upper node such as CU).

The core network 30 is, for example, a core network (5G Core Network: 5GC) corresponding to NR, but is not limited to this. The device on the core network 30 (hereinafter, also referred to as “core network device”) manages mobility such as paging and location registration of the terminal 10. The core network device may be connected to the base station 20 via a predetermined interface (for example, S1 or NG interface).

The core network device is, for example, an Access and Mobility Management Function (AMF) that manages C-plane information (for example, information related to access and movement management, etc.), and a User that controls transmission of U-plane information (for example, user data). At least one of Plane Function (UPF) and the like may be included.

In the wireless communication system 1, the terminal 10 receives a downlink (DL) signal from the base station 20 and / or transmits an uplink signal (uplink: UL). One or more carriers may be configured in the terminal 10. The bandwidth of each carrier is, for example, 5 MHz to 400 MHz. One or a plurality of bandwidth portions (Bandwidth Part: BWP) may be set for one carrier. One BWP has at least a portion of the bandwidth of the carrier.

One or more control resource sets (Control Resource Set: CORESET) may be set in one BWP. CORESET is a time domain and frequency domain resource used for transmission of downlink control channels. For example, CORESET is composed of a predetermined number of symbols (for example, 1 to 3 symbols) and a predetermined number of resource blocks (Resource Block: RB) (for example, 6n (n ≧ 1) RB).

In the following, a physical downlink control channel (PDCCH) will be described as an example of the downlink control channel, but the downlink control channel may be a channel used for transmitting downlink control information (Downlink Control Channel: DCI). The name is not limited to PDCCH.

CORESET includes a plurality of control channel elements (ControlChannelElement: CCE). 1CCE is composed of a predetermined number of resource element groups (Resource Element Group: REG). For example, 1REG may be composed of 1RB (ie, 1 symbol and 12 subcarriers) and 1CCE may be composed of 6REG (ie, 6RB).

The candidate resource in which the PDCCH is placed (hereinafter referred to as "PDCCH candidate") is composed of a predetermined number of CCEs according to the aggregation level (Aggregation Level: AL). For example, when AL = 1, the 1PDCCH candidate is composed of 1CCE, and when AL = 2, the 1PDCCH candidate is composed of 2CCE.

The search space includes each PDCCH candidate composed of one or more CCEs in CORESET associated with the search space. Therefore, it can be said that the search space is composed of at least a part of CORESET associated with the search space. The terminal 10 monitors each PDCCH candidate included in the search space and detects DCI.

Here, monitoring is to decode each PDCCH candidate in the search space according to a predetermined format, and is called "blind decoding". The search space includes a common search space (CSS), which is a common search space for one or more terminals 10, and a UE-specific Search Space (USS), which is a search space unique to the terminal 10. ) And may be included. The search space as described above may be provided for each AL, and a set of one or more AL search spaces may be referred to as a search space set. The "search space" in the present specification may be a search space of a specific AL, or may be a search space set.

Information about each CORESET (hereinafter, referred to as "CORESET information") is given to the terminal 10 from the base station 20. The CORESET information may be, for example, an information item (Information Element: IE) "Control Resource Set" of the radio resource control (RRC). Here, IE may be paraphrased as a parameter. The CORESET information may include, for example, at least one of the following.
-CORESET identification information (for example, RRC IE "controlResourceSetId")
-Period information indicating the period of CORESET (hereinafter referred to as "CORESET period") (for example, RRC IE "duration")
-Frequency domain resource information indicating frequency domain resources constituting CORESET (for example, RRC IE "frequencyDomainResources")

Further, information about each search space (hereinafter, referred to as "search space information") is given to the terminal 10 from the base station 20. The search space information may be, for example, RRC IE "Search Space". The search space information may include, for example, at least one of the following.
-Search space identification information (for example, RRC IE "searchSpaceId")
-CORESET identification information associated with the search space (eg, RRC IE "controlResourceSetId")
-Cycle / offset information indicating the cycle k and offset o for monitoring PDCCH (for example, RRC IE "monitoringSlotPeriodicityAndOffset"), hereinafter, the cycle k and offset o are referred to as monitoring cycle k and monitoring offset o, respectively.
-Monitoring period information indicating the monitoring period T of PDCCH (for example, RRC IE "duration"), hereinafter, the period T is referred to as a monitoring period T.
-Monitoring symbol information indicating the first symbol to monitor PDCCH in the slot (for example, RRC IE "monitoring SymbolsWithinSlot")
-Search space group information (for example, RRC IE "searchSpaceGroupIdList") indicating one or more groups to which the search space is associated (hereinafter, "search space group").

The terminal 10 controls PDCCH monitoring based on the CORESET information and the search space information. FIG. 2 is a diagram showing an example of PDCCH monitoring in NR. For example, FIG. 2 shows an example of PDCCH monitoring using the search space # 1 associated with CORESET # 1.

In FIG. 2, for example, the monitoring cycle k is 10 slots and the monitoring period T is 4 slots. Further, it is assumed that the CORESET period for CORESET # 1 associated with the search space # 1 is 2 symbols, and the frequency domain resource for CORESET # 1 is 6n (n ≧ 1) RB.

The terminal 10 monitors based on the radio frame number n _f , the slot numbers n _{s, f} _in the radio frame # n f, the number of slots N _s, f in the radio frame, the monitoring cycle k, and the monitoring offset o. Determine the start slot of the period. For example, the terminal 10 determines a slot having a slot number satisfying the following equation (1) (slot # 0 in FIG. 2) as the start slot of the monitoring period.
(Equation 1)
(N _f · N _{s, f} + n _{s, f} −o) mod k = 0

Note that FIG. 2 is merely an example, the radio frame number n _f , the slot numbers n _{s, f} _in the radio frame # n f, the number of slots N _s, f in the radio frame, the monitoring cycle k, and monitoring. The offset o and the like are not limited to those shown in the figure. For example, in FIGS. 2 and 2 onward, since an example in which the subcarrier spacing (SCS) is 15 kHz is illustrated, the number of slots in the wireless frame is N _{s, f} = 10, but the present invention is not limited to this. When an SCS larger than 15 kHz (for example, 30 kHz, 60 kHz, 120 kHz, etc.) is used, the number of slots N _{s, f} in the wireless frame increases.

Further, in the monitoring symbol information shown in FIG. 2, among the bits corresponding to the symbols # 0 to # 13, the bit corresponding to the symbol # 0 is “1”. Therefore, in each slot (hereinafter, referred to as “monitoring slot”) within the monitoring period, CORESET # 1 associated with the search space # 1 is arranged in two symbols starting from symbol # 0. As mentioned above, the search space # 1 is at least a part of the CORESET # 1 associated with the search space # 1.

The terminal 10 monitors each PDCCH candidate in the search space # 1 by using the T slot continuous from the start slot # 0 determined as described above as a monitoring slot. The terminal 10 detects the PDCCH for the terminal 10 by monitoring each PDCCH candidate in the search space # 1. The detection of the PDCCH may be rephrased as the detection of DCI in a predetermined format in which a cyclic redundancy check (Cyclic Redundancy Check: CRC) is scrambled by a predetermined radio network temporary identifier (RNTI).

The DCI format is different from the DCI format used for downlink shared channel scheduling (for example, DCI format 1_X), the DCI format used for uplink shared channel scheduling (for example, DCI format 0_X), and scheduling. The DCI format used in the application (for example, DCI format 2_X) and the like may be included. Here, X is a positive integer.

FIG. 3 is a diagram showing another example of PDCCH monitoring in NR. For example, FIG. 3 shows an example of PDCCH monitoring using the search space # 2 associated with CORESET # 2. FIG. 3 differs from FIG. 2 in that a single search space is set in that a plurality of search spaces are set in each slot within the monitoring period. In FIG. 3, the differences from FIG. 2 will be mainly described.

In FIG. 3, the CORESET period for CORESET # 2 is one symbol. In the monitoring symbol information, among the bits corresponding to the symbols # 0 to # 13, the bit corresponding to the symbols # 0 and # 7 is “1”. Therefore, in each slot during the monitoring period, the CORESET # 2 associated with the search space # 2 is arranged in one symbol starting from the symbols # 0 and # 7, respectively.

The terminal 10 monitors each PDCCH candidate in the search space # 2 of each of the symbols # 0 and # 7 in each slot within the monitoring period. In FIG. 3, the terminal 10 does not detect PDCCH in the search space # 2 of symbol # 0, but detects PDCCH in the search space # 2 of symbol # 7.

In this way, in NR, the terminal 10 monitors the PDCCH within the monitoring period set in the predetermined cycle. Further, one or more search spaces can be set in each slot within the monitoring period, and the terminal 10 may monitor one or more search spaces in each slot.

By the way, in NR release 17, the performance is lower than the terminals for high-speed large capacity (enhanced Mobile Broadband: eMBB) and ultra-reliable and low latency Communications (URLLC) introduced in release 15 or 16. It is being considered to support functions for terminals that assume the price range. The terminal is also called a Reduced capability (RedCap) terminal, a device, etc., and is used for, for example, an industrial wireless sensor, a surveillance camera (video serveilance), a wearable device, or the like. May be good.

RedCap terminals are expected to have higher performance than terminals for power saving and wide area communication (Low Power Wide Area: LPWA), and the carriers used by RedCap terminals are, for example, with a bandwidth of 20 MHz, 50 MHz, 100 MHz, or the like. There may be. The LPWA includes, for example, Category 1, Long Term Evolution for Machine-type-communication (LTE-M) and Narrow Band IoT (NB-IoT) that operate in LTE RAT. The maximum bandwidth of Category 1 is 20 MHz, the maximum bandwidth of LTE-M is 1.4 MHz (6 RB), and the maximum bandwidth of NB-IoT is 180 kHz (1 RB). As described above, the RedCap terminal may be used as a terminal in the middle range between those for eMBB and URLLC and those for LPWA.

When a RedCap terminal is assumed as the terminal 10, it is considered to repeatedly transmit PDCCH in order to compensate for the decrease in coverage due to the narrowing of the carrier bandwidth. Specifically, it is assumed that the base station 20 repeatedly transmits the PDCCH in the time domain and / or the frequency domain.

However, the terminal 10 performs PDCCH reception processing (for example, demodulation, decoding, etc.) on the assumption that the PDCCH of the first transmission is transmitted in each search space set within the monitoring period of a predetermined cycle. Therefore, when the PDCCH is repeatedly transmitted, the terminal 10 may not be able to properly monitor the repeatedly transmitted PDCCH by the existing monitoring method.

Therefore, in the present embodiment, (1) monitoring of PDCCH repeatedly transmitted using different time domain resources (hereinafter referred to as "first PDCCH monitoring"), (2) transmission using different frequency domain resources. A combination of PDCCH monitoring (hereinafter referred to as "second PDCCH monitoring") and (3) first and second PDCCH monitoring will be described. Further, in the present embodiment, (4) control related to switching of the search space group (hereinafter, referred to as “switching control”) will also be described.

(1) First PDCCH Monitoring In the first PDCCH monitoring, monitoring of PDCCH repeatedly transmitted in the time domain will be described. The terminal 10 repeatedly transmits the PDCCH using different time domain resources within the monitoring period T of a predetermined cycle based on the information regarding the repetition of the PDCCH included in the search space information (hereinafter referred to as “repetition information”). Control monitoring.

Here, the different time domain resources may be, for example, different slots in the monitoring period T of a predetermined cycle, or different symbols in the same slot in the monitoring period T. In this way, the PDCCH may be repeated between different slots within one or more monitoring periods (hereinafter referred to as "inter-slot repetition") or within the same slot during the monitoring period. It may be repeated (hereinafter referred to as "intra-slot repetition").

Further, the repetition information may include information indicating the repetition number R of the PDCCH, or may include information indicating the maximum value of the repetition number R. In the latter case, the terminal 10 may determine the number of iterations R based on the maximum value and a predetermined field value in the DCI. The number of repetitions R may be referred to as a repetition level or the like.

Further, the repetition information may include information indicating the start slot of the repetition of PDCCH (hereinafter, referred to as "start slot information"). Further, the repetition information may include information indicating a symbol in which the PDCCH is repeated (hereinafter, referred to as “repetition symbol information”) in the case of repetition in the slot.

Based on the repetition information as described above, the terminal 10 may set a search space used for monitoring PDCCH transmitted by repetition between slots and / or repetition in slots. The terminal 10 may detect the PDCCH by monitoring the PDCCH candidate in the set search space.

In this way, when the PDCCH is repeatedly transmitted, the search space for monitoring the PDCCH is also set repeatedly, so that the repetition of the PDCCH may be rephrased as the repetition of the search space. Hereinafter, the search space is also referred to as a “repetition search space”.

(1.1) Inter-slot repetition Inter-slot repetition may be applied to a plurality of slots within one monitoring period T of a predetermined cycle monitoring period T, or may be applied to a plurality of slots within a predetermined cycle monitoring period T. It may be applied in a plurality of slots spanning a plurality of monitoring periods T.

In the inter-slot repetition, the monitoring slot # ki ( _i = 0, ..., R-1) in which the 1st to Rth PDCCHs are transmitted within the monitoring period T of a predetermined cycle based on the repetition number R of the PDCCH repetition. To decide. Specifically, in addition to the repetition number R, the terminal 10 has a repetition start slot # k ₀ , a radio frame number n _f , slot numbers n _{s, f} _in the radio frame # n f, and a slot in the radio frame. The monitoring slot # ki ( _i = 0, ..., R-1) may be determined based on at least one of the number N _{s, f} , the monitoring cycle k, the monitoring interval T, and the monitoring offset o. For example, the terminal 10 uses a continuous slot starting from k ₀ to k _R-1 , which has a slot number satisfying the following equation (2), as a monitoring slot # ki ( _i = 0, ..., R-1). You may decide.

The repeating start slot # k ₀ may be explicitly notified from the base station 20 to the terminal 10 by the start slot information. Alternatively, the start slot # k ₀ may be derived by the terminal 10 itself based on the implicit information without the explicit notification of the start slot information. For example, the terminal 10 may consider the start slot of the monitoring period T as the repeat start slot # k ₀ .

FIG. 4 is a diagram showing a first example of inter-slot repetition according to the present embodiment. In FIG. 4, as described with reference to FIG. 2, the monitoring period T of the search space # 1 is set in slots # 0 to # 3 of each radio frame based on the search space information of the search space # 1. Further, based on the CORESET information of CORESET # 1 associated with the search space # 1, CORESET # 1 is arranged in symbols # 0 to 2 of each slot in the monitoring period T. The search space # 1 is used as a search space for repetition.

For example, in FIG. 4, the repetition number R of the PDCCH is 2, and the repetition start slot # k ₀ is the same as the start slot # 0 of the monitoring period T of the predetermined cycle. It is assumed that the terminal 10 is a continuous R slot from the repetition start slot # k ₀ , and the PDCCH of the repetition number R is transmitted. In FIG. 4, since R = 2, the terminal 10 assumes that the first and second PDCCHs are mapped in the search spaces # 1 of the slots # k ₀ and # k ₁ , respectively, and the slot # Monitor the search space # 1 for each of k ₀ and # k ₁ .

For example, in FIG. 4, the terminal 10 detects the first PDCCH by monitoring the search space # 1 in slot # k ₀ , and detects the second PDCCH by monitoring the search space # 1 in slot # k ₁ . If the terminal 10 succeeds in decoding the _{i +} 1th PDCCH in the slot # ki (0 ≦ _i ≦ R-1), the terminal 10 may stop monitoring the search space # 1 after the slot # ki + 1. , Monitoring may be continued for the number of repetitions R. Further, the terminal 10 may synthesize the i + 1th PDCCH from the first PDCCH for decoding the i + 1th PDCCH.

FIG. 5 is a diagram showing a second example of inter-slot repetition according to the present embodiment. The preconditions of FIG. 5 are the same as those of FIG. 4, and the differences from FIG. 4 will be mainly described. In FIG. 5, the terminal 10 determines the repeat start slot # k ₀ based on the start slot information from the base station 20. The start slot information may be, for example, the period and offset of the repeating start slot, or the offset from the start slot of the monitoring period T.

For example, in FIG. 5, the start slot information is assumed to indicate an offset (here, 2) from the start slot # 0 of the monitoring period T. The terminal 10 shifts the repeating start slot # k ₀ to slot # 2 based on the start slot # 0 of the monitoring period T determined by the above equation (1) and the offset “2” indicated by the start slot information. decide. In FIG. 5, the number of repetitions R = 4, and the slot # 3 in which the search space # 1 for the second PDCCH is provided is the final slot of the monitoring period T. Therefore, the search spaces # 1 for the third and fourth PDCCHs are provided in slots # 0 and # 1 of the next monitoring period T.

In this way, the terminal 10 counts up the slot numbers one by one from the repeating start slot # k ₀ (here, slot # 2 of the wireless frame # 0) and monitors the monitoring slot # ki (0 ≦ _i ≦ R−). If 1) is determined and the monitoring slot # ki _{+ 1} becomes a slot other than the monitoring period T (here, slot # 4 of the wireless frame # 0), the monitoring slot # ki _{+ 1} is set to the start slot of the next monitoring period (here). Then, the slot # 0) of the wireless frame # 1 after the kt slot of the slot # 4 of the wireless frame # 0 may be determined. The terminal 10 may count up i by 1 and repeat the above process until i becomes equal to the number of repetitions R-1. In this way, the R monitoring slots # k ₀ to # k _R-1 may span a plurality of monitoring periods.

FIG. 6 is a diagram showing a third example of inter-slot repetition according to the present embodiment. In FIG. 6, as described with reference to FIG. 3, the monitoring period T of the search space # 2 is set in slots # 0 to # 3 of each radio frame based on the search space information of the search space # 2. Further, based on the CORESET information of CORESET # 2 associated with the search space # 2, CORESET # 2 is arranged at the symbols # 0 and # 7 of each slot in the monitoring period T. The search space # 2 is used as a repeat search space.

FIG. 6 differs from FIGS. 4 and 5 in that a plurality of search spaces are provided in each monitoring slot #ki ( _i = 0, ..., R-1) for repetition. As shown in FIG. 6, different _PDCCHs may be transmitted within the plurality of search spaces of each monitoring slot # ki. The different PDCCH may be a PDCCH that transmits different DCIs.

For example, in FIG. 6, the first PDCCH # 1 is mapped in the search space # 2 of the symbol # 0 of the monitoring slot # k ₀ , and the first PDCCH # 1 is mapped in the search space # 2 of the symbol # 7 of the monitoring slot # k ₁ . PDCCH # 2 is mapped. Further, the second PDCCH # 1 is mapped in the search space # 2 of the symbol # 0 of the next monitoring slot # k ₁ , and the second PDCCH is mapped in the search space # 2 of the symbol # 7 of the monitoring slot # k ₁ . # 2 is mapped.

As described above, in the inter-slot repetition, when a plurality of search spaces are provided in each of the R monitoring slots # ki ( _i = 0, ..., R-1) for repetition, the plurality of search spaces are different. By mapping the PDCCH, multiple PDCCHs can be repeated between monitoring slots.

(1.2) In-slot repetition In-slot repetition may be applied with different symbols in the same slot during the monitoring period T of a predetermined cycle. In the following, the differences from the above (1.1) will be mainly described.

For intra-slot repetition, the base station 20 transmits repetitive symbol information indicating a symbol in which PDCCH is repeated in one slot (that is, the second and subsequent PDCCH is transmitted) to the terminal 10. The terminal 10 controls monitoring of PDCCH repeatedly transmitted by a plurality of symbols in the same slot based on the monitoring symbol information and the repeating symbol information.

FIG. 7 is a diagram showing a first example of in-slot repetition according to the present embodiment. In FIG. 7, the monitoring period T of the search space # 3 is set in slots # 0 to # 3 of each radio frame based on the search space information of the search space # 3. Further, based on the CORESET information of CORESET # 3 associated with the search space # 3, CORESET # 3 is arranged at the symbols # 0, # 4, # 8, and # 12 of each monitoring slot. The search space # 3 is used as a search space for repetition.

In FIG. 7, the monitoring symbol information in the search space information indicates the first symbols # 0, # 4, # 8, and # 12 in which the search space # 3 is arranged. Further, the repeated symbol information in the search space information indicates the first symbols # 4 and # 12 in which the search space # 3 for monitoring the PDCCH from the second time onward is arranged. For example, in FIG. 7, the repeating symbol information is a 14-bit bitmap corresponding to each of symbols # 0 to # 13, and the bits corresponding to symbols # 4 and # 12 are “1”. Therefore, the terminal 10 assumes that the first PDCCH is mapped in the search space # 3 of the symbol # 0 and the second PDCCH is mapped in the search space # 3 of the symbol # 4. Symbols # 8 and # 12 are the same as symbols # 0 and # 4.

In FIG. 7, in the repeated symbol information, the bit corresponding to the first symbol in which the second and subsequent PDCCHs can be arranged in one slot is set to "1", and the first symbol in which the PDCCH of the first transmission can be arranged is set to "1". The bit corresponding to is set to "0", but is not limited to this. The repetitive symbol information may be information that can identify whether the PDCCH of the first transmission or the PDCCH of the second and subsequent transmissions is the symbol to be arranged. For example, the first PDCCH in which the second and subsequent PDCCHs can be arranged in one slot. The bit corresponding to the symbol may be set to "0" and the bit corresponding to the first symbol in which the PDCCH of the first transmission can be placed may be set to "1".

(1.3) Combination of inter-slot repetition and intra-slot repetition The above-mentioned inter-slot repetition and intra-slot repetition may be combined. Specifically, the terminal 10 may monitor one or more PDCCHs repeatedly transmitted by a plurality of symbols straddling a plurality of monitoring slots.

FIG. 8 is a diagram showing an example of a combination of inter-slot repetition and intra-slot repetition according to the present embodiment. In FIG. 8, the search space # 3 and CORESET # 3 are set as in FIG. 7, but are different from FIG. 7 in that the number of repetitions R = 7. In the following, the differences from FIG. 7 will be mainly described. In FIG. 8, the repeated symbol information indicates the first symbols # 4, # 8 and # 12 in which the search space # 3 for monitoring the PDCCH from the second time onward is arranged.

As shown in FIG. 8, the pattern of the symbol to which the PDCCH is transmitted from the second time onward indicated by the repeated symbol information may be repeated over a plurality of monitoring slots #ki (0 ≦ _i ≦ R _s -1). good. Here, the number R _s of the monitoring slots for the _PDCCH having the number of repetitions R is, for example, ceil { It may be derived by (R-1) / n _ss }. In FIG. 8, since the repetition number R is 7 and the number n _ss of the search space is 3, the R _s is ceil {(7-1) / 3} = 2.

In FIG. 8, monitoring slots # k ₀ and # k ₁ are included in different monitoring periods, but it goes without saying that they may be included in the same monitoring period.

(1.4) Signaling of repetitive information Next, signaling of repetitive information used for the first PDCCH monitoring will be described. As described above, the repetition information may include at least one of information indicating the repetition number R of the PDCCH, information indicating the maximum value of the repetition number R, start slot information, and repetition symbol information.

The repeat information may be transmitted from the base station 20 to the terminal 10 using the higher layer parameter. The upper layer parameter may be an RRC layer parameter (for example, RRC IE) or a medium access control (MAC) layer parameter (for example, a medium access control element (MAC CE)). May be good.

FIG. 9 is a diagram showing an example of search space information according to this embodiment. FIG. 9 shows an example in which the RRC IE “SearchSpace” as the search space information includes the above-mentioned repeated information. Here, as the repetition information, information indicating the number of repetitions R (for example, RRC IE "numRepetition-r17") and repetition symbol information (for example, RRC IE "repetitionSymbolsWithinSlot-r17") are shown.

As shown in FIG. 9, the repetition number R may be, for example, any one of 1, 2, 4, 8, 16, 32, 64, 128 or 256. Further, the RRC IE "repetitionSymbolsWithinSlot-r17" as the repetitive symbol information may be a 14-bit bitmap.

Note that FIG. 9 is only an example, and the RRC IE "SearchSpace" may include information indicating the maximum value of the repetition number R instead of the information indicating the repetition number R of the PDCCH as the repetition information. Further, the RRC IE "Search Space" may include start slot information.

FIG. 10 is a diagram showing an example of deriving the number of repetitions according to the present embodiment. FIG. 10 shows an example of deriving the number of repetitions R when the search space information (for example, RRC IE “SearchSpace”) includes information indicating the maximum value of the number of repetitions R of PDCCH.

The terminal 10 may determine the number of repetitions R of the PDCCH based on the value of the predetermined field in the DCI and the above maximum value rep_max. For example, in FIG. 10, the value of the predetermined field in the DCI is associated with the parameters r1 to r4 for deriving the repetition number R. The terminal 10 determines the number of repetitions R based on the maximum value rep_max and the parameter.

For example, in FIG. 10, when the maximum value rep_max of the repetition number R of PDCCH is 8, and the value of the predetermined field in DCI is “00”, the repetition number R = rep_max / 8 = 1. Similarly, if the value of the predetermined field in the DCI is "01", "10" or "11", the number of repetitions R = 2, 4 or 8.

As shown in FIG. 10, by dynamically specifying the repetition number R of PDCCH based on DCI, the coverage extension range can be controlled more flexibly.

As described above, in the first PDCCH monitoring, since the repeat search space is set based on the repeat information included in the search space information, it is repeatedly transmitted using different time domain resources within the monitoring period of a predetermined cycle. The monitoring of the PDCCH to be performed can be appropriately controlled.

(2) Second PDCCH Monitoring In the second PDCCH monitoring, monitoring of PDCCH repeatedly transmitted in the frequency domain will be described. The terminal 10 controls monitoring of PDCCH repeatedly transmitted between a plurality of frequency domain resources corresponding to one or more CORESETs.

The repetitive search space used for monitoring the PDCCH may be associated with a single CORESET (see 2.1 below) or multiple CORESETs (see 2.2 below). ..

(2.1) Repeated search space associated with a single CORESET When a repeating search space is associated with a single CORESET, multiple frequency domain resources to which the PDCCH is repeatedly transmitted are in the single CORESET. It may correspond.

The CORESET information regarding the CORESET may include a plurality of frequency domain resource information indicating the plurality of frequency domain resources, respectively (see 2.1.1 below), and indicates one of the plurality of frequency domain resources. It may include frequency domain resource information and frequency domain information indicating the number of repetitions of PDCCH (see 2.1.2 below), or frequency domain resource information indicating one of the plurality of frequency domain resources. It may include offset information indicating the offset (see 2.1.3 below).

(2.1.1) First Determination Example of Frequency Domain Resource for Repetition In the first determination example, the terminal 10 is based on a plurality of frequency domain resource information included in the CORESET information relating to a single CORESET. Determine multiple frequency domain resources for the CORESET.

FIG. 11 is a diagram showing a first determination example of the frequency domain resource for repetition according to the present embodiment. For example, in FIG. 11, CORESET # 1 is associated with the search space # 1 used as the repeatable search space. The CORESET information for CORESET # 1 includes the frequency domain resource information 1 indicating the frequency domain resource # 0 for CORESET # 1 and the frequency domain resource information 1 indicating the frequency domain resources # 1 and # 2 for CORESET # 1, respectively. And 2 shall be included.

The frequency domain resource information and the frequency

domain resource information

1 and 2 may be bitmaps including bits corresponding to a predetermined number of RB groups (hereinafter, referred to as “RB group”), respectively. The length of the bitmap may be determined based on the number of RBs constituting the BWP and the number of RBs constituting one RB group. In FIG. 11, it is assumed that the 1RB group is composed of continuous 6RBs, but the present invention is not limited to this, and the 1RB group may be composed of one or more RBs.

In the frequency domain resource information and the frequency

domain resource information

1 and 2, the bits corresponding to the RB groups constituting the frequency domain resources # 0, # 1 and # 2, respectively, are set to "1" and correspond to other RB groups. The bit to be used may be set to "0". The frequency domain resources # 0, # 1 and # 2 for the same CORESET # 1 are each composed of different RB groups, and may not be allowed to include overlapping RB groups.

As shown in FIG. 11, the terminal 10 may assume that the search space # 1 is arranged in each of the frequency domain resources # 0, # 1 and # 2 for CORESET # 1. The terminal 10 uses the search space # 1 to control i + 1th PDCCH monitoring transmitted within the frequency domain resource # i (here, 0 ≦ i ≦ 2) using the search space # 1. You may.

Note that in FIG. 11, it is assumed that the CORESET period of CORESET # 1 composed of different frequency domain resources # 0, # 1 and # 2 is the same, but the CORESET period is not limited to this and may be different. As described above, the CORESET period of CORESET # 1 may be common to a plurality of frequency domain resources for CORESET # 1, or may be set for each frequency domain resource for CORESET # 1.

FIG. 12 is a diagram showing a first example of CORESET information according to the present embodiment. For example, FIG. 12 shows an example in which the RRC IE “ControlResourceSet” as the CORESET information includes a plurality of frequency domain resource information indicating a plurality of frequency domain resources for the CORESET identified by the RRC IE “controlResourceSetId”.

For example, in the RRC IE "ControlResourceSet" shown in FIG. 12, the frequency domain resources for the first transmission (first time) may be indicated by the RRC IE "frequencyDomainResources". On the other hand, the frequency domain resources for the second and subsequent times may be indicated by RRC IE "frequencyDomainResourcesRepetition-r17".

In this way, the CORESET information includes the frequency domain resource information for the first transmission (for example, RRC IE "frequencyDomainResources") and the frequency domain resource information for the second and subsequent transmissions (for example, RRC IE "frequencyDomainResourcesRepetition-r17"). It may include a list. The number of entries in the list may be, for example, equal to the number of iterations R-1. Each of the frequency domain resource information for the second and subsequent times may indicate an RB group that does not overlap with the frequency domain resource information for the first transmission.

In FIG. 12, RRC IE "frequencyDomainResources" and "frequencyDomainResourcesRepetition-r17" are bitmaps including bits corresponding to each RB group in the BWP and have 45 bits, but if it is information indicating frequency domain resources, , Not limited to these.

(2.1.2) Second determination example of frequency domain resource for repetition In the second determination example, the terminal 10 is based on the frequency domain resource information and the repetition number information included in the CORESET information regarding a single CORESET. To determine a plurality of frequency domain resources for the CORESET. In the second setting example, the differences from the first setting example will be mainly described.

FIG. 13 is a diagram showing a second determination example of the frequency domain resource for repetition according to the present embodiment. In FIG. 13, the CORESET information for CORESET # 1 is the repetition number R of PDCCH (here, the number R of PDCCH is replaced with the plurality of frequency

domain resource information

1 and 2 indicating the frequency domain resources # 1 and # 2 for CORESET # 1, respectively. , R = 3), which is different from FIG. 11 in that it includes the repetition number information.

As shown in FIG. 13, the terminal 10 assumes that frequency domain resources # 0, # 1 and # 2 equal to the number of repetitions R are continuously allocated for COSET # 1 from frequency domain resource # 0. Further, the terminal 10 assumes that the number of RBs of the frequency domain resources # 1 and # 2 is equal to the number of RBs of the frequency domain resource # 0 (here, 6 RB).

As described above, the terminal 10 is determined based on the RB (more specifically, the position and number of RBs) assigned to the frequency domain resource # 0 indicated by the frequency domain resource information and the repetition number R. It may be assumed that the search space # 1 is arranged in each of the frequency domain resources # 0, # 1 and # 2.

FIG. 14 is a diagram showing a second example of CORESET information according to the present embodiment. For example, in FIG. 14, the RRC IE “ControlResourceSet” as the CORESET information uses the RRC IE “numRepetition-r17” indicating the repetition number R of PDCCH (or CORESET) instead of the RRC IE “frequencyDomainResourcesRepetition-r17” in FIG. include. As shown in FIG. 14, the repetition number R may be set to, for example, 1, 2, 4, 8, 16 or 32.

As described above, the CORESET information may include the repetition number information (for example, RRC IE "numRepetition-r17") in addition to the frequency domain resource information for the initial transmission (for example, RRC IE "frequencyDomainResources"). Since the number of repetitions information has a smaller number of bits than the second and subsequent frequency domain resource information shown in FIG. 12, the second setting example reduces the overhead due to the CORESET information as compared with the first setting example. can.

(2.1.3) Third determination example of frequency domain resource for repetition In the third determination example, the terminal 10 is based on the frequency domain resource information and the offset information included in the CORESET information relating to a single CORESET. , Determine multiple frequency domain resources for the CORESET. In the third setting example, the differences from the first or second setting example will be mainly described.

FIG. 15 is a diagram showing a second determination example of the frequency domain resource for repetition according to the present embodiment. FIG. 15 is different from FIG. 13 in that the CORESET information for CORESET # 1 includes offset information indicating the offset for each of the frequency domain resources # 1 and # 2 instead of the repetition number information.

For example, in FIG. 15, the offset information indicates the offsets n _f1 and n _f2 of the frequency domain resources # 1 and # 2 with respect to the starting RB group of the frequency domain resource # 0, respectively. The value of the offset may indicate the number of RB groups to be shifted. In FIG. 15, the offset n _f1 = 2, and the frequency domain resource # 1 is shifted from the start RB group of the frequency domain resource # 0 by 2 RB groups. As described above, the shift amount indicated by the offset value may be an integral multiple of the number of RBs (for example, 6RB) constituting the 1RB group, but is not limited to this, and may be a predetermined number of RBs.

In the terminal 10, the frequency domain resource # 0 indicated by the frequency domain resource information and the frequency domain resources # 1 and # 2 shifted by the offsets n _f1 and n _f2 from the start RB group of the frequency domain resource # 0 are used for CORESET # 1. Assume to be assigned. Further, the terminal 10 assumes that the number of RBs of the frequency domain resources # 1 and # 2 is equal to the number of RBs of the frequency domain resource # 0 (here, 6 RB).

In FIG. 15, the offset _nfi for the frequency domain resource # i (i ≧ 1) is assumed to be an offset with respect to the start RB group of the frequency domain resource # 0, but is not limited to this. The offset _nfi of the frequency domain resource # i (i ≧ 1) may be an offset of the frequency domain resource # 0 with respect to the final RB group.

Further, the offset _nfi of the frequency domain resource # i (i ≧ 1) may be an offset with respect to the start RB group of the frequency domain resource # i-1. Alternatively, the offset _nfi of the frequency domain resource # i (i ≧ 1) may be an offset of the frequency domain resource # i-1 with respect to the final RB group.

FIG. 16 is a diagram showing a third example of CORESET information according to the present embodiment. For example, in FIG. 16, the RRC IE “ControlResourceSet” as the CORESET information is replaced with the RRC IE “frequencyDomainResourcesRepetition-r17” in FIG. 12, which indicates the offset of each frequency domain resource for the second and subsequent repetitions. -ShiftList -r17 "may be included. RRC IE "rbg-ShiftList-r17" is a list of RRC IE "RBG-Shift-r17" indicating the offset of each frequency domain resource, and RRC IE "RBG-Shift-r17" is, for example, an offset value 1 to 1 to 32 may be specified. Further, the RRC IE "ControlResourceSet" may include the RRC IE "numRepetition-r17" indicating the repetition number R of the PDCCH.

As described above, the CORESET information includes the frequency domain resource information for the first transmission (for example, RRC IE "frequencyDomainResources") and the offset information (for example, RRC) indicating the offset of each frequency domain resource for the second and subsequent repetitions. IE "rbg-ShiftList-r17") may be included. Since the offset information has a smaller number of bits than the second and subsequent frequency domain resource information shown in FIG. 12, in the third setting example, the overhead due to the CORESET information can be reduced as compared with the first setting example. .. Further, since the frequency domain resource #i can be distributed and arranged in the BWP, the frequency diversity gain can be improved as compared with the second setting example.

In the above, the base station 20 specifies the offset _nfi for each frequency domain resource #i (0 <i <R) for the second and subsequent repetitions, but the present invention is not limited to this. The offset n _f common to the frequency domain resource # i (0 <i <R) for the second and subsequent repetitions may be specified by the base station 20. The CORESET information may include offset information indicating the common offset n _f .

FIG. 17 is a diagram showing a fourth determination example of the frequency domain resource for repetition according to the present embodiment. FIG. 17 is different from FIG. 15 in that a common offset n _f is used for the frequency domain resource #i (0 <i <R) for the second and subsequent repetitions. As shown in FIG. 17, the common offset n _f may be the offset of the frequency domain resource # i with respect to the starting RB group of the frequency domain resource # i-1 (i> 0). Although not shown, the common offset n _f may be the offset of the frequency domain resource # i with respect to the final RB group of the frequency domain resource # i-1 (i> 0).

As shown in FIG. 17, the CORESET information includes offset information indicating an offset common to each frequency domain resource for the second and subsequent repetitions, and repetition information indicating the repetition number R of PDCCH (or CORESET). good. The terminal 10 is from the frequency domain resource # 1 and the start RB group of the frequency domain resource # 1 shifted by the common offset _nf from the start RB group of the frequency domain resource # 0 and the frequency domain resource # 0 indicated by the frequency domain resource information. It is assumed that the frequency domain resource # 2 shifted by the common offset n _f is allocated for CORESET # 1. Further, the terminal 10 assumes that the number of RBs of the frequency domain resources # 1 and # 2 is equal to the number of RBs of the frequency domain resource # 0 (here, 6 RB).

As described above, when the repeat search space is associated with a single CORESET, PDCCH can be repeated among a plurality of frequency domain resources by setting a plurality of frequency domain resources for the single CORESET. .. In this case, by changing the CORESET information, it is possible to repeat PDCCH between a plurality of frequency domain resources without changing the search space information.

(2.2) Repeated search space associated with a plurality of CORESETs When a repeated search space is associated with a plurality of CORESETs, the plurality of frequency domain resources to which the PDCCH is repeatedly transmitted correspond to each of the plurality of CORESETs. You may. The search space information regarding the repeatable search space may include identification information of each of the plurality of CORESETs.

The terminal 10 determines the frequency domain resource of each of the plurality of CORESETs based on the plurality of CORESET information of each of the plurality of CORESETs. Specifically, the frequency domain resource of each of the plurality of CORESETs is determined based on the frequency domain resource information included in each of the plurality of CORESET information.

FIG. 18 is a diagram showing a fifth determination example of the frequency domain resource for repetition according to the present embodiment. For example, in FIG. 18, CORESET # 1, # 2 and # 3 are associated with the search space # 1 used as the repeatable search space, and the CORESET information of each of CORESET # 1, # 2 and # 3 is the frequency. It shall include frequency domain resource information indicating region resources # 0, # 1 and # 2, respectively. The frequency domain resource information is as described with reference to FIG.

As shown in FIG. 18, in the terminal 10, the search space # 1 is arranged in each of the frequency domain resources # 0, # 1 and # 2 for CORESET # 1, # 2 and # 3 associated with the search space # 1. You may assume that. Further, the terminal 10 uses the frequency domain resource for CORESET # i (here, i ≧ 1), for example, and assumes that the i-th repeated PDCCH is transmitted, and searches associated with CORESET # i. Space # 1 may be monitored.

Note that in FIG. 18, it is assumed that the CORESET periods of CORESET # 1, # 2, and # 3 associated with the repeatable search space # 1 are the same, but the CORESET period is not limited to this, and may be different. In this way, when a plurality of CORESETs are associated with the repeat search space # 1, the CORESET period, frequency domain resources, and the like can be flexibly set for each iteration.

FIG. 19 is a diagram showing an example of search space information according to the present embodiment. For example, FIG. 19 shows an example in which the RRC IE “SearchSpace” as the search space information includes identification information of a plurality of CORESETs associated with the repeating search space.

For example, in the RRC IE "Search Space" shown in FIG. 19, the CORESET in which the repeated search space for monitoring the PDCCH of the first transmission (first time) is arranged may be indicated by the RRC IE "controlResourceSetId". On the other hand, the CORESET in which the repeated search space for the second and subsequent PDCCH monitoring is arranged may be indicated by RRC IE "controlResourceSetRepetition-r17".

In this way, the search space information is a list of CORESET identification information (for example, RRC IE "ControlResoruceSetId") for the second and subsequent transmissions in addition to the CORESET identification information for the first transmission (for example, RRC IE "controlResourceSetId"). (For example, RRC IE "controlResourceSetRepetition-r17") may be included. The number of entries in the list may be, for example, equal to the number of iterations R-1.

The CORESET information regarding the CORESET for repetition as described above may be notified from the base station 20 to the terminal 10 in distinction from the CORESET for the initial transmission. Specifically, the list of the CORESET information may be included in the information regarding PDCCH (hereinafter, referred to as "PDCCH information"). The PDCCH information may include individual PDCCH information (hereinafter referred to as "individual PDCCH information") in the terminal 10 and / or PDCCH information common to one or more terminals 10 (hereinafter referred to as "common PDCCH information"). ..

FIG. 20 is a diagram showing an example of PDCCH information according to the present embodiment. In FIG. 20, RRC IE “PDCCH-Config” as individual PDCCH information and RRC IE “PDCCH-ConfigCommon” as common PDCCH information provide CORESET information and identification information of a plurality of CORESETs associated with the repeat search space. An example including is shown.

For example, the RRC IE "PDCCH-Config" shown in FIG. 20 includes the RRC IE "repetitionControlResourceSetToAddModList-r17", and the RRC IE "repetitionControlResourceSetToAddModList-r17" has a repeated search space for monitoring the PDCCH for the second and subsequent times. It may be a list of RRC IE "Control Resource Set" as CORESET information. Further, the RRC IE "PDCCH-Config" may include the RRC IE "repetitionControlResourceSetToReleaseList-r17" which is a list of the RRC IE "ControlResourceSetId" as the identification information of the CORESET. Further, the RRC IE "PDCCH-ConfigCommon" shown in FIG. 20 may include the above RRC IE "repetitionControlResourceSetToAddModList-r17".

In this way, the individual PDCCH information and the common PDCCH information include the CORESET information (for example, RRC IE "repetitionControlResourceSetToAddModList-r17") in which the search space for repetition is arranged, so that the individual PDCCH and the terminal 10 have individual PDCCH and the terminal 10. Both PDCCHs common to one or more terminals 10 can be repeatedly transmitted using a plurality of CORESETs.

As described above, when the repeat search space is associated with a plurality of CORESETs, PDCCH can be repeated among the plurality of frequency domain resources by setting a plurality of frequency domain resources corresponding to each of the plurality of CORESETs. .. In this case, by changing the search space information and / or the PDCCH information, it is possible to repeat the PDCCH between a plurality of frequency domain resources without changing the CORESET information.

(3) Combination of 1st and 2nd PDCCH Monitoring In the 1st PDCCH monitoring, the terminals 10 are the same between different time domain resources (for example, between slots and / or between symbols in the same slot). It is assumed that the monitoring of the PDCCH repeatedly transmitted is controlled by using the frequency domain resource, but the present invention is not limited to this.

In the first PDCCH monitoring, the terminal 10 monitors PDCCH repeatedly transmitted between different time domain resources (for example, between slots and / or between symbols in the same slot) using different frequency domain resources. May be controlled. That is, the first PDCCH monitoring can be combined with the second PDCCH monitoring.

Further, in the second PDCCH monitoring, the terminal 10 monitors the PDCCH repeatedly transmitted between a plurality of frequency domain resources corresponding to one or more CORESETs in the same time domain resource within the monitoring period of a predetermined cycle. Is assumed to be controlled, but it is not limited to this.

In the second PDCCH monitoring, the terminal 10 controls monitoring of PDCCH repeatedly transmitted between a plurality of frequency domain resources corresponding to one or more CORESETs in different time domain resources within a monitoring period of a predetermined cycle. You may. That is, the second PDCCH monitoring can be combined with the first PDCCH monitoring.

In this way, repeating PDCCH using different frequency domain resources for each time domain resource within the monitoring period of a predetermined cycle by combining the first and second PDCCH monitoring is called "frequency hopping". May be called.

FIG. 21 is a diagram showing an example of repeated transmission of PDCCH to which frequency hopping according to the present embodiment is applied. For example, FIG. 21 shows, as an example, a combination of the slot-to-slot repetition shown in FIG. 2 and the first determination example of the frequency domain resource for repetition shown in FIG. Although not shown, it goes without saying that any aspect described in the first and second PDCCH monitoring may be combined.

As shown in FIG. 21, different frequency domain resources # 0 and # 1 corresponding to CORESET # 1 are used between the repeat monitoring slots # 0 and # 1. In the terminal 10, the first PDCCH is transmitted in the monitoring slot # 0 using the frequency domain resource # 0, whereas the second PDCCH is transmitted in the monitoring slot # 1 using the frequency domain resource # 1. Assuming that, the monitoring of the search space # 1 may be controlled.

In FIG. 21, frequency domain resources # 0 and # 1 having a number equal to the repetition number R of PDCCH (for example, R = 2 in FIG. 21) are provided for COSET # 1 associated with the repetition search space # 1. It shall be set, but it is not limited to this. The number NFR of the frequency domain resources set for the _CORESET # 1 may be less than or greater than the number of repetitions R. When the number of repetitions R> the number of frequency domain resources _NFR , the repetition search space may be arranged in the same frequency domain resource for each predetermined number of repetitions. For example, the frequency domain resource # 0 may be used for the odd-numbered repetition, and the frequency domain resource # 1 may be used for the even-numbered repetition.

(4) Search space group switching control Next, search space group switching control will be described. In the present embodiment, the repetitive search spaces described in (1) to (3) above may be associated with one or more search space groups. For example, the search space information (eg, RRC IE "SearchSpace") may include search space group information (eg, RRC IE "searchSpaceGroupIdList") indicating one or more search space groups associated with the repeating search space.

The terminal 10 controls the switching of the search space group based on the value of the predetermined field of DCI. FIG. 22 is a diagram showing an example of switching the search space group according to the present embodiment. FIG. 22 shows an example in which the terminal 10 switches the search space group used for monitoring the repeatedly transmitted PDCCH from the search space groups # 1 to # 2.

For example, in FIG. 22, the monitoring cycle k ₂ of the repeating search space associated with the search space group # 2 is longer than the monitoring cycle k ₁ of the repeating search space associated with the search space group # 1. In FIG. 22, it is assumed that the monitoring periods T1 and T2 of the search spaces associated with the search space groups # ₁ and # ₂ , respectively, are the same, but the present invention is not limited to this. The configuration of the search space associated with each search space group (for example, monitoring cycle k, monitoring period T, start slot of monitoring period T, number of PDCCH candidates for each aggregation level, symbols in which the search space is arranged in the monitoring slot, etc. ) Can be freely set according to the search space information for the search space.

In FIG. 22, the terminal 10 controls the switching of the search space group based on the value of the predetermined field in the DCI. Further, the terminal 10 controls PDCCH monitoring using the repeating search space associated with the search space group based on the value of the predetermined field in the DCI.

FIG. 23 is a diagram showing an example of DCI used for switching control of the search space group according to the present embodiment. As shown in FIG. 23, the DCI is a DCI format used for scheduling a downlink shared channel (for example, DCI format 1_X) or a DCI format used for scheduling an uplink shared channel (for example, DCI format 0_X). You may. Here, X is an arbitrary integer.

In the following, as an example of the downlink shared channel and the uplink shared channel, the physical downlink shared channel (Physical Downlink Shared Channel: PDSCH) and the physical uplink shared channel (Physical Uplink Shared Channel: PUSCH) will be described, but the downlink shared channel and the uplink shared channel will be described. The name of the channel is not limited to PDSCH and PUSCH as long as it is a channel used for transmitting user data and / or upper layer parameters.

As shown in FIG. 23, the DCI format 1_X or 0_X may include a search space group switching field used for switching the search space group, a resource allocation field indicating a resource allocated to the PDSCH or PUSCH, and the like.

Alternatively, as shown in FIG. 23, the DCI may be in a DCI format (for example, DCI format 2_X) used for other than PDSCH or PUSCH scheduling. Here, X is an arbitrary integer. As shown in FIG. 23, the DCI format 2_X may include M (M ≧ 1) search space group switching fields # 1 to # M. Here, M may be, for example, the number of cells C set in the terminal 10. It should be noted that the DCI format 2_X is not limited to that shown, and of course, a single search space group switching field may be included.

FIG. 24 is a diagram showing an example of the value of the search group switching field according to the present embodiment. The search group switching field in FIGS. 23 and 24 may be a predetermined field in the DCI, and the name is not limited to this. Further, in FIG. 24, it is assumed that the search group switching field has 2 bits, but the present invention is not limited to this, and it may be 1 bit or more.

As shown in FIG. 24, each value of the search group switching field may indicate the search space group of the switching destination. In FIG. 24, the search space group of the switching destination indicated by each value of the search group switching field is set in the terminal 10 by the upper layer parameter, but the present invention is not limited to this, and the search space group may be predetermined in the specifications.

Further, the terminal 10 may indicate the value of the search group switching field as information regarding the number of repetitions R of PDCCH monitored in the search space associated with the search space group indicated by the value. For example, in FIG. 24, the information regarding the repetition number R is the parameter values r1 to r4, but the information is not limited to this, and may be the repetition number R itself. In addition to the DCI, the terminal 10 receives information indicating the maximum value rep_max of the repetition number R.

As shown in FIG. 24, the terminal 10 may determine the number of repetitions R by the maximum value rep_max and the parameter value indicated by the value of the search group switching field. Note that FIG. 24 is merely an example, and it goes without saying that the number of repetitions R associated with each value of the search group switching field may be defined in the specifications.

Further, when the DCI including the search group switching field is in the DCI format (for example, DCI format 1_X or 0_X) used for scheduling the PDSCH or PUSCH, the terminal 10 uses the PDSCH based on the value of the search group switching field. Alternatively, the number of repetitions R of PUSCH may be determined. As described above, the repetition number R derived from the value of the search space group switching field of the DCI format 1_X or 0_X in FIG. 23 may be the repetition number R of PDSCH or PUSCH. The repetition number R of the PDSCH or PUSCH can be derived in the same manner as the repetition number R of the PDCCH.

Further, the DCI format (for example, DCI format 1_X or 0_X) used for scheduling PDSCH or PUSCH uses a predetermined field value used for deriving the repetition number R of PDSCH or PUSCH in addition to the value of the search group switching field. It may be included. In this case, the terminal 10 may determine the repetition number R of PDCCH based on the value of the search space group switching field, and may determine the repetition number R of PDSCH or PUSCH based on the predetermined field value.

Further, the terminal 10 uses the value of the search space group switching field in the DCI format (for example, DCI format 2_X) used for scheduling other than the PDSCH or PUSCH scheduling to derive the repetition number R of the PDSCH and / or PUSCH. May be done. Alternatively, the value of the search space group switching field in the DCI format is used to derive the repetition number R of the PDCCH, and the other field values in the DCI format are used to derive the repetition number R of the PDSCH or PUSCH. May be good.

As described above, when the search space group is dynamically switched using DCI, the repetition number R of PDCCH monitored in the search space associated with the search space group can be dynamically controlled. Therefore, the monitoring of the PDCCH can be appropriately controlled. In addition, the number of PDSCH or PUSCH iterations scheduled by the DCI can be dynamically controlled.

(Configuration of wireless communication system)
Next, the configuration of each device of the wireless communication system 1 as described above will be described. It should be noted that the following configurations are for showing the configurations necessary for the description of the present embodiment, and do not exclude that each device includes functional blocks other than those shown in the drawings.

<Hardware configuration>
FIG. 25 is a diagram showing an example of the hardware configuration of each device in the wireless communication system according to the present embodiment. Each device (for example, terminal 10, base station 20, CN30, etc.) in the wireless communication system 1 includes a processor 11, a storage device 12, a communication device 13 that performs wired or wireless communication, an input device that accepts various input operations, and various types. The input / output device 14 that outputs information is included.

The processor 11 is, for example, a CPU (Central Processing Unit) and controls each device in the wireless communication system 1. The processor 11 may execute various processes described in the present embodiment by reading the program from the storage device 12 and executing the program. Each device in the wireless communication system 1 may be composed of one or a plurality of processors 11. In addition, each device may be called a computer.

The storage device 12 is composed of, for example, a memory, a storage such as an HDD (Hard Disk Drive) and / or an SSD (Solid State Drive). The storage device 12 may store various information (for example, a program executed by the processor 11) necessary for executing the process by the processor 11.

The communication device 13 is a device that communicates via a wired and / or wireless network, and may include, for example, a network card, a communication module, a chip, an antenna, and the like. Further, the communication device 13 may include an RF (Radio Frequency) device that performs processing related to an amplifier and a radio signal, and a BB (BaseBand) device that performs baseband signal processing.

The RF device generates a radio signal transmitted from the antenna A by performing D / A conversion, modulation, frequency conversion, power amplification, etc. on the digital baseband signal received from the BB device, for example. Further, the RF device generates a digital baseband signal by performing frequency conversion, demodulation, A / D conversion, etc. on the radio signal received from the antenna and transmits it to the BB device. The BB apparatus performs a process of converting a digital baseband signal into a packet and a process of converting a packet into a digital baseband signal.

The input / output device 14 includes, for example, an input device such as a keyboard, a touch panel, a mouse and / or a microphone, and an output device such as a display and / or a speaker.

The hardware configuration explained above is just an example. Each device in the wireless communication system 1 may omit a part of the hardware shown in FIG. 25, or may include hardware not shown in FIG. 25. Further, the hardware shown in FIG. 4 may be composed of one or a plurality of chips.

<Functional block configuration>
≪Terminal≫
FIG. 26 is a diagram showing an example of the functional block configuration of the terminal according to the present embodiment. As shown in FIG. 26, the terminal 10 includes a receiving unit 101, a transmitting unit 102, and a control unit 103.

Note that all or part of the functions realized by the receiving unit 101 and the transmitting unit 102 can be realized by using the communication device 13. Further, all or a part of the functions realized by the receiving unit 101 and the transmitting unit 102, and the control unit 103 can be realized by the processor 11 executing the program stored in the storage device 12. In addition, the program can be stored in a storage medium. The storage medium in which the program is stored may be a computer-readable non-transitory storage medium (Non-transitory computer readable medium). The non-temporary storage medium is not particularly limited, but may be, for example, a storage medium such as a USB memory or a CD-ROM.

The receiving unit 101 receives the downlink signal. Further, the receiving unit 101 may receive the information and / or data transmitted via the downlink signal. Here, "receiving" may include, for example, performing processing related to reception of at least one of reception, demapping, demodulation, decoding, monitoring, and measurement of a radio signal.

The downlink signal may include, for example, at least one of the PDCCH, PDSCH, downlink reference signal, synchronization signal, broadcast channel, and the like. The downlink reference signal may include, for example, a PDCCH or a PDSCH demodulation reference signal (Demodulation Reference Signal: DMRS) or the like.

Also, the receiving unit 101 receives the DCI. Specifically, the receiving unit 101 may detect the PDCCH by monitoring the search space and receive the DCI transmitted via the PDCCH. The receiving unit 101 may receive the PDSCH based on the DCI, and may receive the user data and / or the upper layer parameter transmitted via the PDSCH. Further, the receiving unit 101 may transmit a DCI including a value of a predetermined field used for switching the search space group (for example, FIG. 23).

The receiving unit 101 may receive search space information (for example, FIGS. 9 and 19) related to the search space associated with the control resource set (CORESET). In addition, the receiving unit 101 may receive CORESET information (for example, FIGS. 12, 14, 16) relating to one or more CORESETs associated with the search space.

Further, the receiving unit 101 may receive the PDCCH information (for example, FIG. 20). The PDCCH information may be for each predetermined bandwidth (for example, BWP or cell C) set in the terminal 10, and the CORESET information regarding one or more CORESETs used within the predetermined bandwidth and one or more CORESET information. It may include search space information about the search space.

Further, the receiving unit 101 may receive information indicating the maximum value of the number of repetitions R (for example, FIG. 24). The information may be included in the search space information.

Further, the receiving unit 101 may synthesize the PDCCH repeatedly transmitted and decode the DCI based on the synthesis result. Alternatively, the receiving unit 101 may decode the DCI based on each PDCCH without synthesizing the PDCCH repeatedly transmitted.

The transmission unit 102 transmits an uplink signal. Further, the transmission unit 102 may transmit information and / or data transmitted via an uplink signal. Here, "transmitting" may include performing processing related to transmission such as at least one of coding, modulation, mapping, and transmission of a radio signal, for example. The uplink signal may include, for example, at least one of the PUSCH, uplink reference signal, and the like. The uplink reference signal may include, for example, a PUSCH DMRS or the like.

The control unit 103 performs various controls on the terminal 10. Specifically, the control unit 103 may control the monitoring of the downlink control channel using the search space within the monitoring period T of a predetermined cycle based on the search space information and / or the CORESET information.

The control unit 103 controls the monitoring of the PDCCH repeatedly transmitted between different slots within the monitoring period T and / or within the same slot based on the repetition information regarding the repetition of the PDCCH included in the search space information. It may be (see (1) above).

Here, the repetition information may include information indicating the repetition number R of PDCCH. The control unit 103 may determine the different slots based on the number of repetitions R (for example, FIGS. 4 to 6, 8 and 9).

Further, the repetition information may include information indicating the maximum value of the repetition number R of PDCCH. The control unit 103 may determine the different slots based on the number of iterations R determined based on the maximum value and a predetermined field value in the DCI (eg, FIGS. 4-6, 8 and 10).

Further, the repetition information may include information indicating the start slot # k ₀ of the repetition of PDCCH. The control unit 103 may determine the different slots based on the start slot # k ₀ (eg, FIGS. 4-8).

The different slots may be a plurality of slots within one monitoring period T of the predetermined cycle monitoring period T (for example, FIG. 4), or a plurality of the plurality of monitoring periods T of the predetermined cycle. There may be a plurality of slots spanning the period of (for example, FIGS. 5, 6 and 8).

Further, the repetitive information may include repetitive symbol information indicating a symbol in which PDCCH is repeated. The control unit 103 may determine a plurality of symbols for monitoring the PDCCH in the same slot based on the repetitive symbol information and the monitoring symbol information indicating the symbol for monitoring the PDCCH (for example, FIG. 7). And 8).

The control unit 103 may control the monitoring of PDCCH repeatedly transmitted using the same frequency domain resource between the different slots and / or within the same slot (see (1) above). Further, the control unit 103 may control monitoring of PDCCH repeatedly transmitted using different frequency domain resources in the different slots and / or the same slot (see (3) above, for example, FIG. 21).

The control unit 103 may control PDCCH monitoring that is repeatedly transmitted between a plurality of frequency domain resources corresponding to the one or more CORESETs (see (2) above).

Here, the search space is associated with a single CORESET, and the plurality of frequency domain resources may correspond to the single CORESET (see (2.1) above).

The CORESET information for the single CORESET may include a plurality of frequency domain resource information indicating each of the plurality of frequency domain resources. The control unit 103 may determine the plurality of frequency domain resources based on the plurality of frequency domain resource information (for example, FIGS. 11 and 12).

Further, the CORESET information for the single CORESET may include the frequency domain resource information indicating one of the frequency domain resources and the repetition number information indicating the repetition number R of the PDCCH. The control unit 103 may determine the plurality of frequency domain resources based on the frequency domain resource information and the repetition number information (for example, FIGS. 13 and 14).

Further, the CORESET information for the single CORESET includes the frequency domain resource information indicating one of the plurality of frequency domain resources and the offset for the other frequency domain resource among the plurality of frequency domain resources. It may include the indicated offset information. The control unit 103 may determine the plurality of frequency domain resources based on the frequency domain resource information and the offset information (for example, FIGS. 15 to 17).

Further, the search space is associated with a plurality of CORESETs, and the plurality of frequency domain resources may correspond to the plurality of CORESETs (see (2.2) above).

The control unit 103 may determine the plurality of frequency domain resources based on the plurality of CORESET information related to each of the plurality of CORESETs (for example, FIGS. 18 to 20).

The control unit 103 may determine the monitoring period T of a predetermined cycle for monitoring the PDCCH using the search space based on the search space information. Further, the control unit 103 may determine the plurality of frequency domain resources corresponding to the same time domain resource within the monitoring period T (see (2) above). Alternatively, a plurality of frequency domain resources corresponding to different time domain resources within the monitoring period T may be determined (see (3) above, for example, FIG. 21).

Further, when the receiving unit 101 succeeds in decoding the i + 1 (0 ≦ i <R-1) PDCCH, the control unit 103 may stop the i + 2nd and subsequent PDCCH monitoring. For example, when the control unit 103 succeeds in decoding the _i + 1th PDCCH in the slot # ki, the monitoring of the repeat search space provided after the slot # ki _{+ 1} may be stopped, or the repetition number R may be stopped. Minute monitoring may be continued. Similarly, when the control unit 103 succeeds in decoding the i + 1th PDCCH in the frequency resource # i, the monitoring of the repeat search space provided after the frequency resource # i + 1 may be stopped, or the number of repetitions may be stopped. R-minute monitoring may be continued.

Further, the control unit 103 may control the switching of the search space group based on the value of the predetermined field in the DCI. The control unit 103 may determine the number of repetitions 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).

Further, the control unit 103 determines the number of repetitions R of the PDCCH to be monitored using the search space associated with the search space group after switching, based on the maximum value of the number of repetitions R of the PDCCH and the predetermined field value in the DCI. It may be done (for example, FIG. 24).

Further, when the control unit 103 controls the switching of the search space group based on the value of the predetermined field in the DCI, the control unit 103 may determine the number of repetitions of the PDSCH or PUSCH scheduled by the DCI.

≪Base station≫
FIG. 27 is a diagram showing an example of the functional block configuration of the base station according to the present embodiment. As shown in FIG. 27, the base station 20 includes a receiving unit 201, a transmitting unit 202, and a control unit 203.

Note that all or part of the functions realized by the receiving unit 201 and the transmitting unit 202 can be realized by using the communication device 13. Further, all or a part of the functions realized by the receiving unit 201 and the transmitting unit 202 and the control unit 203 can be realized by the processor 11 executing the program stored in the storage device 12. In addition, the program can be stored in a storage medium. The storage medium in which the program is stored may be a non-temporary storage medium that can be read by a computer. The non-temporary storage medium is not particularly limited, but may be, for example, a storage medium such as a USB memory or a CD-ROM.

The receiving unit 201 receives the upstream signal. In addition, the receiving unit 201 may receive the information and / or data transmitted via the uplink signal.

The transmission unit 202 transmits the downlink signal. Further, the transmission unit 202 may transmit information and / or data transmitted via the downlink signal.

Further, the transmission unit 202 transmits DCI. Specifically, the transmission unit 202 may transmit DCI via PDCCH. The transmission unit 202 may transmit the PDSCH scheduled by DCI.

Further, the transmission unit 202 may transmit a DCI including a value of a predetermined field used for switching the search space group (for example, FIG. 23). The value of the predetermined field may indicate information about the number of iterations of the downlink control channel monitored using the search space associated with the search space group. The value of the predetermined field may indicate the information regarding the number of repetitions of the downlink shared channel or the uplink shared channel scheduled by the downlink control information.

The transmission unit 202 may transmit search space information (for example, FIGS. 9 and 19) related to the search space associated with the control resource set (CORESET). In addition, the receiving unit 101 may transmit CORESET information (for example, FIGS. 12, 14, 16) relating to one or more CORESETs associated with the search space. Further, the transmission unit 202 may transmit the PDCCH information (for example, FIG. 20). Further, the transmission unit 202 may transmit information indicating the maximum value of the number of repetitions R (for example, FIG. 24).

The control unit 203 performs various controls on the base station 20. Specifically, the control unit 203 may control the transmission of the downlink control channel using the search space within the monitoring period T of a predetermined cycle based on the search space information and / or the CORESET information.

The control unit 203 may control the repeated transmission of the PDCCH between different slots within the monitoring period T and / or within the same slot based on the repeated information regarding the repetition of the PDCCH included in the search space information ( See (1) above).

Here, the repetition information may include information indicating the repetition number R of PDCCH. The control unit 203 may determine the different slots based on the number of repetitions R (for example, FIGS. 4 to 6 and 9).

Further, the repetition information may include information indicating the maximum value of the repetition number R of PDCCH. The control unit 203 may determine the different slots based on the number of repetitions R determined based on the maximum value and the predetermined field value in the DCI (for example, FIGS. 4 to 6 and 10).

Further, the repetition information may include information indicating the start slot # k ₀ of the repetition of PDCCH. The control unit 203 may determine the different slot based on the start slot # k ₀ (for example, FIGS. 4 to 8).

The different slots may be a plurality of slots within one monitoring period T of the monitoring period T of the predetermined cycle (for example, FIG. 4), or a plurality of slots of the monitoring period T of the predetermined cycle. It may be a plurality of slots over a period (for example, FIGS. 5 and 6).

Further, the repetitive information may include repetitive symbol information indicating a symbol in which PDCCH is repeated. The control unit 203 may determine a plurality of symbols for repeatedly transmitting the PDCCH in the same slot based on the repetitive symbol information and the monitoring symbol information indicating the symbol for monitoring the PDCCH (for example, FIG. 7 and 8).

The control unit 203 may control repeated transmission of PDCCH using the same frequency domain resource between the different slots and / or within the same slot (see (1) above). Further, the control unit 203 may control repeated transmission of PDCCH using different frequency domain resources in the different slots and / or the same slot (see (3) above).

The control unit 203 may control the repeated transmission of PDCCH between a plurality of frequency domain resources corresponding to the one or more CORESETs (see (2) above).

The CORESET information for the single CORESET may include a plurality of frequency domain resource information indicating each of the plurality of frequency domain resources. The control unit 203 may determine the plurality of frequency domain resources based on the plurality of frequency domain resource information (for example, FIGS. 11 and 12).

Further, the CORESET information for the single CORESET may include the frequency domain resource information indicating one of the frequency domain resources and the repetition number information indicating the repetition number R of the PDCCH. The control unit 203 may determine the plurality of frequency domain resources based on the frequency domain resource information and the repetition number information (for example, FIGS. 13 and 14).

Further, the CORESET information for the single CORESET includes the frequency domain resource information indicating one of the plurality of frequency domain resources and the offset for the other frequency domain resource among the plurality of frequency domain resources. It may include the indicated offset information. The control unit 203 may determine the plurality of frequency domain resources based on the frequency domain resource information and the offset information (for example, FIGS. 15 to 17).

The control unit 203 may determine the plurality of frequency domain resources based on the plurality of CORESET information related to each of the plurality of CORESETs (for example, FIGS. 18 to 20).

The control unit 203 may determine the monitoring period T of a predetermined cycle in which the PDCCH is repeatedly transmitted using the search space based on the search space information. Further, the control unit 203 may determine the plurality of frequency domain resources corresponding to the same time domain resource within the monitoring period T (see (1) above). Alternatively, a plurality of frequency domain resources corresponding to different time domain resources within the monitoring period T may be determined (see (3) above).

Further, the control unit 203 may control the switching of the search space group (see (4) above).

(Operation of wireless communication system)
Next, the operation of the wireless communication system 1 configured as described above will be described. It should be noted that FIGS. 28 and 29 are merely examples, and it goes without saying that some steps may be omitted or steps (not shown) may be performed.

FIG. 28 is a diagram showing an example of the operation of PDCCH monitoring in the wireless communication system according to the present embodiment. As shown in FIG. 28, in step S101, the terminal 10 receives one or more search space information and / or one or more CORESET information. The search space information and / or the CORESET information may be included in, for example, an RRC reconstruction message, but is not limited thereto.

In step S102, the terminal 10 sets a search space for monitoring PDCCH repeatedly transmitted within the monitoring period T of a predetermined cycle based on the search space information and / or the CORESET information.

In step S103, the terminal 10 monitors the PDCCH repeatedly transmitted using different time domain resources and / or different frequency domain resources using the search space set in step S102 ((1) to (1) to (1) above. See 3)).

As described above, according to the wireless communication system 1 according to the present embodiment, it is possible to appropriately control the monitoring of PDCCH repeatedly transmitted using different time domain resources and / or different frequency domain resources.

FIG. 29 is a diagram showing an example of the operation of switching the search space group in the wireless communication system according to the present embodiment. As shown in FIG. 29, in step S201, the terminal 10 receives the DCI.

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

In step S203, the terminal 10 determines the number of repetitions R of the PDCCH monitored in the search space associated with the search space group to be switched to in step S202 based on the value of the predetermined field in the DCI received in step S201. You may.

In step S204, the terminal 10 monitors the PDCCH repeatedly transmitted by the number of repetitions R determined in step S203 using the search space (see (1) to (3) above).

(Other embodiments)
The various signals, information, and parameters in the above embodiment may be signaled at any layer. That is, the various signals, information, and parameters are the signals, information, and signals of any layer such as an upper layer (for example, Non Access Stratum (NAS) layer, RRC layer, MAC layer, etc.) and a lower layer (for example, physical layer). It may be replaced with a parameter. Further, the notification of the predetermined information is not limited to the explicit one, and may be implicitly (for example, by not notifying the information or by using other information).

Further, the names of various signals, information, parameters, IE, channels, time units, and frequency units in the above embodiments are merely examples, and may be replaced with other names. For example, the slot may have any name as long as it is a time unit having a predetermined number of symbols. Further, RB may have any name as long as it is a frequency unit having a predetermined number of subcarriers.

The use of the terminal 10 in the above embodiment (for example, for RedCap, IoT, etc.) is not limited to the examples, and any use (for example, eMBB, URLLC, Device-to-) as long as it has the same function. It may be used in Device (D2D), Vehicle-to-Everything (V2X), etc.). Further, the format of various information is not limited to the above embodiment, and bit representation (0 or 1), boolean value (Boolean: true or false), integer value, character, or the like may be appropriately changed. Further, the singular and plural in the above embodiment may be changed from each other.

The embodiments described above are for facilitating the understanding of the present disclosure, and are not for limiting and interpreting the present disclosure. The flowchart, sequence, each element included in the embodiment, its arrangement, index, condition, and the like described in the embodiment are not limited to those exemplified, and can be changed as appropriate. Further, it is possible to partially replace or combine at least a part of the configurations described in the above-described embodiment.

Claims

A receiver that receives control resource set information about one or more control resource sets associated with a search space.
A control unit that controls monitoring of the downlink control channel using the search space based on the control resource set information is provided.
The control unit controls monitoring of the downlink control channel, which is repeatedly transmitted between a plurality of frequency domain resources corresponding to the one or more control resource sets.
Terminal.
The search space is associated with a single control resource set, and the plurality of frequency domain resources correspond to the single control resource set.
The terminal according to claim 1.
The control resource set information includes a plurality of frequency domain resource information indicating each of the plurality of frequency domain resources.
The control unit determines the plurality of frequency domain resources based on the plurality of frequency domain resource information.
The terminal according to claim 2.
The control resource set information includes frequency domain resource information indicating one of the plurality of frequency domain resources and repetition number information indicating the number of repetitions of the downlink control channel.
The control unit determines the plurality of frequency domain resources based on the frequency domain resource information and the repetition number information.
The terminal according to claim 2.
The control resource set information includes frequency domain resource information indicating one of the plurality of frequency domain resources and offset information indicating an offset for another frequency domain resource among the plurality of frequency domain resources. Including
The control unit determines the plurality of frequency domain resources based on the frequency domain resource information and the offset information.
The terminal according to claim 2.
The search space is associated with a plurality of control resource sets, and the plurality of frequency domain resources correspond to the plurality of control resource sets, respectively.
The control resource set information is a plurality of control resource set information for each of the plurality of control resource sets.
The control unit determines the plurality of frequency domain resources based on the plurality of control resource set information.
The terminal according to claim 1.
The receiving unit receives the search space information regarding the search space, and receives the search space information.
Based on the search space information, the control unit determines a period of a predetermined cycle for monitoring the downlink control channel using the search space, and the plurality of frequency domain resources corresponding to the same time domain resource within the period. The terminal according to any one of claims 1 to 6.
The receiving unit receives the search space information regarding the search space, and receives the search space information.
Based on the search space information, the control unit determines a period of a predetermined cycle for monitoring the downlink control channel using the search space, and determines a plurality of frequency domain resources corresponding to different time domain resources within the period. do,
The terminal according to any one of claims 1 to 6.
A transmitter that sends control resource set information about one or more control resource sets associated with a search space.
A control unit that controls transmission of a downlink control channel using the search space based on the control resource set information is provided.
The control unit controls repeated transmission of the downlink control channel between a plurality of frequency domain resources corresponding to the one or more control resource sets.
base station.
The process of receiving control resource set information for one or more control resource sets associated with a search space, and
A step of controlling monitoring of a downlink control channel using the search space based on the control resource set information is provided.
In the control step, the monitoring of the downlink control channel, which is repeatedly transmitted between a plurality of frequency domain resources corresponding to the one or more control resource sets, is controlled.
Wireless communication method of the terminal.