WO2022070364A1

WO2022070364A1 - Terminal, and radio communication method

Info

Publication number: WO2022070364A1
Application number: PCT/JP2020/037332
Authority: WO
Inventors: 浩樹原田; 祐輝松村; 聡永田
Original assignee: 株式会社Ｎｔｔドコモ
Priority date: 2020-09-30
Filing date: 2020-09-30
Publication date: 2022-04-07
Also published as: JPWO2022070364A1

Abstract

A terminal (UE200) receives at least one reference signal among a first reference signal transmitted from a serving cell and a second reference signal transmitted from a non-serving cell, and monitors the quality of a radio link in at least one cell among the serving cell and the non-serving cell, on the basis of the received at least one reference signal.

Description

Terminal and wireless communication method

This disclosure relates to terminals and wireless communication methods.

The 3rd Generation Partnership Project (3GPP) has specified LongTermEvolution (LTE), and has specified LTE-Advanced (hereinafter referred to as LTE including LTE-Advanced) for the purpose of further speeding up LTE. In 3GPP, specifications for LTE successor systems called 5G New Radio (NR) or Next Generation (NG) are being studied.

For example, in 3GPP Release 16, inter-cell multi-TRP / panel operation has been proposed as a technology that enables terminals (User Equipment, UE) to send and receive data across multiple cells. ing. In inter-cell multi-TRP / panel operation, one gNB can operate multiple cells via multiple TRP / panels. Therefore, the UE can receive scheduling from a plurality of TRP / panels and send / receive data to / from a plurality of TRP / panels.

In addition, according to 3GPP TS 38.331 v16.1.0 (Non-Patent Document 1), as an information element used for setting wireless link monitoring (RLM) performed to monitor the radio link quality (beam quality) of a cell. , RadioLinkMonitoringConfig (see Figure 5) is disclosed.

Here, when any one of the cells to be operated by the inter-cell multi-TRP / panel operation is a PCell (Primary Cell) or a PS cell (Primary Secondary Cell), the transmission / reception point of the serving cell. RLM is performed based only on the reference signal from (TRP). Further, the RadioLink MonitoringConfig disclosed in Non-Patent Document 1 does not include an information element that can individually identify the cell in which RLM is executed.

Therefore, in the inter-cell multi-TRP / panel operation, even if the connection state with the non-serving cell TRP other than the serving cell is good, the UE will Radio based on the result of RLM performed with the serving cell. May declare Link Failure (RLF).

The RLF declaration as described above is a factor for executing, for example, interruption of communication during execution, execution of RRC (radio resource control) reconnection procedure, or execution of handover procedure for changing Pcell and PScell of UE. Can be. Further, the declaration of RLF as described above may cause unnecessary overhead and delay by, for example, performing an RRC reconnection procedure or a handover procedure for changing the Pcell and PScell of the UE.

Therefore, the following disclosure was made in view of such a situation, and aims to provide a terminal and a wireless communication method capable of efficiently performing inter-cell multi-TRP / panel operation.

One aspect of the present disclosure is a receiving unit (radio signal transmitting / receiving unit 210) that receives at least one reference signal among a first reference signal transmitted from a serving cell and a second reference signal transmitted from a non-serving cell. ), And a control unit (control unit 270) that monitors the quality of the radio link in at least one of the serving cell and the non-serving cell based on the at least one reference signal received by the receiving unit. It is a equipped terminal (UE200).

One aspect of the present disclosure is a step of receiving at least one reference signal among a first reference signal transmitted from a serving cell and a second reference signal transmitted from a non-serving cell, and the at least one reference. A radio communication method comprising a step of monitoring the quality of a radio link in at least one of the serving cell and the non-serving cell based on a signal.

FIG. 1 is an overall schematic configuration diagram of the wireless communication system 10. FIG. 2 is a diagram showing an example in which gNB100 generated three cells via three TRPs. FIG. 3 is a functional block configuration diagram of the UE 200. FIG. 4 is a diagram showing an example in which the UE 200 receives a beam from two cells (cells of PCI # 0 and PCI # 1) formed by the same gNB100. FIG. 5 is a diagram showing a setting example of RadioLink Monitoring Config specified in TS 38.331 (v16.1.0). FIG. 6 is a diagram showing an example of the hardware configuration of the UE 200.

Hereinafter, embodiments will be described based on the drawings. The same functions and configurations are designated by the same or similar reference numerals, and the description thereof will be omitted as appropriate.

(1) Overall Schematic Configuration of Wireless Communication System FIG. 1 is an overall schematic configuration diagram of the wireless communication system 10 according to the present embodiment. The wireless communication system 10 is a wireless communication system according to 5G New Radio (NR), and includes a Next Generation-Radio Access Network 20 (hereinafter, NG-RAN20) and a terminal 200 (hereinafter, UE200). In addition, the wireless communication system 10 corresponds to at least one of Frequency Range (FR) 1 (410 MHz to 7.125 GHz) and FR2 (24.25 GHz to 52.6 GHz), and corresponds to the other frequency bands. May be good.

NG-RAN20 includes a radio base station 100 (hereinafter, gNB100). The specific configuration of the wireless communication system 10 including the number of gNBs and UEs is not limited to the example shown in FIG.

NG-RAN20 actually includes multiple NG-RANNodes, specifically gNB (or ng-eNB), and is connected to a core network (5GC, not shown) according to 5G. In addition, NG-RAN20 and 5GC may be simply expressed as "network".

GNB100 is a wireless base station that complies with 5G, and executes wireless communication according to UE200 and 5G. The gNB100 and UE200 are Massive MIMO (Multiple-Input Multiple-Output) and multiple component carriers (CC) that generate more directional beam BM by controlling radio signals transmitted from multiple antenna elements. Carrier aggregation (CA) used in a bundle, dual connectivity (DC) that communicates simultaneously between the UE and each of the two NG-RAN Nodes, and wireless backhaul between wireless communication nodes such as gNB and wireless to the UE. It can support Integrated Access and Backhaul (IAB), which is integrated with access.

Here, the gNB 100 includes a plurality of transmission / reception points (TRPs) as shown in the figure. In the present embodiment, the TRP is a unit of transmission / reception equipment capable of forming a cell, and may be a panel or simply an antenna. The number of TRPs is not limited to the illustrated example (three in the example of FIG. 1). FIG. 2 is a diagram showing an example in which gNB100 generated three cells via three TRPs. That is, for the purpose of explaining the present embodiment, an example in which three cells of physical cell ID (PCI) # 1, PCI # 2, and PCI # 3 are formed is shown as shown in the figure. In addition, gNB100 can form serving cells and non-serving cells for UE200 by controlling a plurality of TRPs. The gNB100 also controls the UE200 to enable radio link monitoring (RLM) for serving and non-serving cells. In the present embodiment, TRP relates to the following, and may be read and carried out as appropriate.
・ CORESET (Control Resource Set) Pool Index = {0, 1}
・ 1st TCI (Transmission Configuration Index) state, 2nd TCI state
・ 1st CDM (Code Division Multiplexing) group, 2nd CDM group (of PDSCH (Physical Downlink Shared Channel) DMRS (Demodulation reference signal))
・ 1st PDSCH, 2nd PDSCH
・ RS port group, panel index, TCI-state / QCL (Quasi Co Location) / spatial-relation group index = {0, 1}
The above is the case where there are two TRPs, and when there are more TRPs, the same settings can be made.

Here, in NR, one serving cell can have a maximum of 8/64 SSBs (SS / PBCH Blocks) in each of the frequency range FR1 / 2. That is, the maximum value of the number of SSBs is determined by the frequency band, and is 8 for FR1 of 410MHz to 7.125GHz and 64 for FR2 of 24.25GHz to 52.6GHz. Therefore, according to the current NR standard, gNB can have a maximum of 8/64 x TRP several SSBs in total when performing inter-cell multi-TRP / panel operation. One TRP can have up to 8/64 SSBs. In the example of FIG. 2, it is shown that 64 SSBs (index (SSB index) # 0- # 63 for identifying SSB) are used for each TRP. Here, in this embodiment, the TRP can form a beam.

In beamforming, the direction of the radio wave from the TRP is narrowed down, so at a certain timing, the synchronization signal can be delivered only to a part of the area that can be covered. For this reason, in the NR synchronization signal, a process called beamforming, in which beamformed signals are sequentially transmitted over the entire coverage area where radio waves can be delivered from the TRP, is executed. Standards have been established on the premise. In that case, in both UE and gNB, which beam the captured synchronization signal corresponds to is specified by using the SSB index.

(2) Functional block configuration of the wireless communication system Next, the functional block configuration of the wireless communication system 10 will be described. Specifically, the functional block configuration of UE200 will be described.

FIG. 3 is a functional block configuration diagram of UE200. As shown in FIG. 3, the UE 200 includes a radio signal transmission / reception unit 210, an amplifier unit 220, a modulation / demodulation unit 230, a control signal / reference signal processing unit 240, a coding / decoding unit 250, a data transmission / reception unit 260, and a control unit 270. .. The UE200 also performs RLM on both serving and non-serving cells under the control of gNB100.

The radio signal transmission / reception unit 210 transmits / receives a radio signal according to NR. The radio signal transmission / reception unit 210 corresponds to Massive MIMO, a CA that bundles a plurality of CCs, and a DC that simultaneously communicates between the UE and each of the two NG-RAN Nodes.

In the present embodiment, the radio signal transmission / reception unit 210 receives beams from a plurality of cells formed by the same base station (gNB100). Here, FIG. 4 is a diagram showing an example in which the UE 200 receives a beam from two cells (cells of PCI # 0 and PCI # 1) formed by the same gNB100.

Further, in the present embodiment, the radio signal transmission / reception unit 210 constitutes a reception unit that receives at least one reference signal among the reference signal transmitted from the serving cell and the reference signal transmitted from the non-serving cell.

The serving cell of this embodiment can be set as, for example, the cell currently being accessed by the UE 200. Further, the non-serving cell of the present embodiment can be set as one or more cells other than the serving cell, for example. Further, in the present embodiment, for example, the serving cell may be set to PCell (Primary Cell) or PS Cell (Primary Secondary Cell), and at least one non-serving cell may be set in association with PCell or PS Cell. Further, according to the present embodiment, in the case as illustrated in FIG. 4, one cell of the two cells PCI # 0 and PCI # 1 is set as the serving cell, and the cell is of the two cells. The other cell of may be set as a non-serving cell.

The amplifier unit 220 is composed of PA (Power Amplifier) / LNA (Low Noise Amplifier) and the like. The amplifier unit 220 amplifies the signal output from the modulation / demodulation unit 230 to a predetermined power level. Further, the amplifier unit 220 amplifies the RF signal output from the radio signal transmission / reception unit 210.

The modulation / demodulation unit 230 executes data modulation / demodulation, transmission power setting, resource block allocation, etc. for each predetermined communication destination (gNB100 or other gNB, or each cell).

The control signal / reference signal processing unit 240 executes processing related to various control signals transmitted / received by the UE 200 and processing related to various reference signals transmitted / received by the UE 200.

Specifically, the control signal / reference signal processing unit 240 receives various control signals transmitted from the gNB 100 via a predetermined control channel, for example, control signals such as a higher layer signal and an RRC parameter. Further, the control signal / reference signal processing unit 240 transmits various control signals to the gNB 100 via a predetermined control channel.

Further, the control signal / reference signal processing unit 240 executes processing using a reference signal (RS) such as Demodulation reference signal (DMRS) and Phase Tracking Reference Signal (PTRS).

DMRS is a reference signal (pilot signal) known between the base station and the terminal of each terminal for estimating the fading channel used for data demodulation. PTRS is a terminal-specific reference signal for the purpose of estimating phase noise, which is a problem in high frequency bands.

In addition to DMRS and PTRS, the reference signal also includes Reference Signal for RLM (RLM-RS), Channel State Information-Reference Signal (CSI-RS) and Sounding Reference Signal (SRS).

Further, the channel includes a control channel and a data channel. Control channels include PDCCH (Physical Downlink Control Channel), PUCCH (Physical Uplink Control Channel), RACH (Random Access Channel, Random Access Radio Network Temporary Identifier (RA-RNTI), Downlink Control Information (DCI)), and Physical. Broadcast Channel (PBCH) etc. are included.

The data channels include PDSCH (Physical Downlink Shared Channel) and PUSCH (Physical Downlink Shared Channel). Data means data transmitted over a data channel.

The coding / decoding unit 250 executes data division / concatenation and channel coding / decoding for each predetermined communication destination (gNB100 or other gNB, or each cell).

Specifically, the coding / decoding unit 250 divides the data output from the data transmission / reception unit 260 into predetermined sizes, and executes channel coding for the divided data. Further, the coding / decoding unit 250 decodes the data output from the modulation / demodulation unit 230 and concatenates the decoded data.

The data transmission / reception unit 260 executes transmission / reception of Protocol Data Unit (PDU) and Service Data Unit (SDU). Specifically, the data transmitter / receiver 260 is a PDU / SDU in a plurality of layers (such as a medium access control layer (MAC), a radio link control layer (RLC), and a packet data convergence protocol layer (PDCP)). Assemble / disassemble the. Further, the data transmission / reception unit 260 transmits a hybrid ARQ (Hybrid automatic repeat request). The data transmission / reception unit 260 may execute data error correction and retransmission control based on the hybrid ARQ.

The control unit 270 controls each functional block constituting the UE 200. In particular, in the present embodiment, the control unit 270 has a radio link quality (beam quality) in at least one of the serving cell and the non-serving cell based on at least one reference signal received by the radio signal transmitting / receiving unit 210. To monitor.

(3) Operation of wireless communication system Next, the operation of the wireless communication system 10 will be described. Specifically, the operation when the UE 200 performs RLM for both the serving cell and the non-serving cell will be described.

(3.1) Outline of operation The gNB100 transmits and receives a reference signal (RLM-RS) for RLM between the UE200 and the TRP of the serving cell, and is used for the RLM between the UE200 and the TRP of the non-serving cell. Controls to send and receive reference signals.

The UE200 sends and receives the reference signal for RLM to and from the TRP of the serving cell, and also sends and receives the reference signal for RLM to and from the TRP of the non-serving cell according to the control of gNB100.

The transmission / reception of setting information regarding the reference signal for RLM in the present disclosure may be performed using, for example, RRC signaling.

The UE200 monitors the quality of the radio link (beam quality) in the serving cell by performing RLM based on the reference signal for RLM received from the TRP of the serving cell. The UE 200 also monitors the quality of the radio link in the non-serving cell by performing RLM based on the reference signal for RLM received from the TRP of the non-serving cell.

The RLM in this disclosure may be performed under the conditions specified in Release 15 of 3GPP, for example.

Specifically, the RLM in the present disclosure may be performed for PCell and PSCell. Further, the RLM in the present disclosure may be performed by a method of monitoring the quality of the radio link in the serving cell and the non-serving cell based on either or both of SSB and CSI-RS. Further, according to the RLM in the present disclosure, the UE 200 can simultaneously monitor the quality of the beam transmitted from the antenna element of the TRP up to eight.

In this disclosure, RLM based on SSB may be performed under the conditions described in Chapter 8.1.2 of 3GPP TS 38.133 V15.4.0, for example. Further, in the present disclosure, RLM based on CSI-RS may be performed under the conditions described in Chapter 8.1.3 of 3GPP TS 38.133 V15.4.0, for example.

In the present disclosure, the transmission / reception of setting information regarding the reference signal for RLM may be performed by a method other than RRC signaling.

Specifically, for example, when a TCI state for receiving a PDCCH containing one or more CSI-RSs is provided from a serving cell and a non-serving cell to the UE200, the reference signal associated with the active TCI state is RLM. It may be monitored as a reference signal for.

The gNB100 is one of the four conditions for performing RLM using the frequencies of FR1 and FR2, as described in Chapters 8.1.7.1 to 8.1.7.4 of 3GPP TS 38.133 V15.4.0. The RS (Reference Signal) resource symbol and the RS resource symbol used for monitoring the quality of the radio link (beam quality) in at least one of the serving cell and the non-serving cell when one of the above conditions is satisfied. Scheduling control is performed to prevent communication other than reception of the reference signal for RLM from being performed in one symbol before and after.

Then, the UE200 (radio signal transmitter / receiver 210) responds to the scheduling control of the gNB100 as described above, and in the RS resource symbol and one symbol before and after the RS resource symbol, the reference for RLM transmitted from the serving cell. Receives at least one of the signal and the reference signal for RLM transmitted from the non-serving cell.

In other words, the control unit 270 assumes that the resource of the reference signal received from the non-serving cell and / or one to several symbols before and after the same symbol and / or one to several symbols before and after are not transmitted to the serving cell or received from the serving cell. do.

Further, according to the scheduling control of gNB100 as described above, for example, the UE200 can prevent PUCCH, PUSCH or SRS from being transmitted to the serving cell in the RS resource symbol and one symbol before and after it.

Further, according to the scheduling control of gNB100 as described above, for example, in the RS resource symbol and one symbol before and after it, the UE200 can prevent the UE200 from receiving PDCCH, PDSCH or CSI-RS for tracking from the serving cell. can.

Further, according to the scheduling control of gNB100 as described above, for example, the UE200 does not receive CSI-RS for CQI (Channel Quality Information) from the serving cell in the RS resource symbol and one symbol before and after it. Can be done.

(3.2) Operation example Next, a specific operation example related to RLM in the present disclosure will be described.

(3.2.1) Operation example 1-1
In this operation example, when the reference signal for RLM is transmitted / received between the UE 200 and the TRP of the non-serving cell, the RadioLink MonitoringConfig (see FIG. 5) which is the information element (setting information) described in Non-Patent Document 1 is used. , An information element that can individually identify the non-serving cell may be added.

FIG. 5 is a diagram showing a setting example of RadioLink Monitoring Config specified in TS 38.331 (v16.1.0). Although the reference signal for RLM is set for the serving cell by RRC signaling, as shown in FIG. 5, there is no IE (information element) / field for displaying the cell ID, and the reference signal transmitted from the non-serving cell is used. Cannot be set for RLM. Therefore, in this operation example, IE (information element) / field that displays the cell ID is added so that the UE200 can specify the cell ID, so that not only the serving cell but also the beam signal of the non-serving cell is used for RLM. It should be possible to refer to it.

In this operation example, as an information element that can individually identify the non-serving cell, for example, an item for indicating the physical cell ID corresponding to the non-serving cell may be added. Further, in this operation example, the information element that can individually identify the non-serving cell may be paraphrased as another term such as cell identification information.

That is, according to this operation example, the UE 200 (radio signal transmission / reception unit 210) can individually identify the non-serving cell in order to transmit / receive a reference signal for RLM to / from the TRP of the non-serving cell. It may be configured to send and receive setting information related to the reference signal for the RLM including the element.

(3.2.1.1) Operation example 1-1-1
In this operation example, as the reference signal for RLM, the reference signal for monitoring the quality of the radio link may be transmitted and received based on the SSB from the non-serving cell. Further, in this operation example, as a reference signal for RLM, it is sufficient to prevent transmission / reception of a reference signal for monitoring the quality of the wireless link based on CSI-RS from a non-serving cell.

That is, according to this operation example, the UE200 (radio signal transmission / reception unit 210) determines the quality of the radio link based on the SSB (SS / PBCH Block) as a reference signal for RLM with the TRP of the non-serving cell. It may be configured to send and receive a reference signal for monitoring. Further, according to this operation example, the UE 200 (radio signal transmission / reception unit 210) can individually identify the non-serving cell in order to transmit / receive a reference signal for RLM to / from the TRP of the non-serving cell. It may be configured to send and receive setting information related to the reference signal for the RLM including the element.

Further, in this operation example, the UE200 performs RLM based on SSB under the conditions described in Chapter 8.1.2 of 3GPP TS 38.133 V15.4.0 based on the reference signal for RLM received from the non-serving cell. It suffices if it is configured.

Further, according to this operation example, the UE200 (radio signal transmitter / receiver 210) monitors the quality of the radio link based on CSI-RS as a reference signal for RLM with the TRP of the non-serving cell. It suffices if it is configured so that the reference signal is not transmitted or received.

(3.2.2.12) Operation example 1-1-2
In this operation example, as the reference signal for RLM, the reference signal for monitoring the quality of the wireless link based on the SSB from the non-serving cell may not be transmitted or received. Further, in this operation example, as the reference signal for RLM, the reference signal for monitoring the quality of the wireless link may be transmitted and received based on CSI-RS from the non-serving cell.

That is, according to this operation example, the UE 200 (radio signal transmission / reception unit 210) includes an information element that can identify the non-serving cell as a reference signal for RLM with the TRP of the non-serving cell, and has a CSI. -It may be configured to send and receive reference signals to monitor the quality of the radio link based on RS. Further, according to this operation example, the UE 200 (radio signal transmission / reception unit 210) can individually identify the non-serving cell in order to transmit / receive a reference signal for RLM to / from the TRP of the non-serving cell. It may be configured to send and receive setting information related to the reference signal for the RLM including the element.

In this operation example, UE200 performs RLM based on CSI-RS under the conditions described in Chapter 8.1.3 of 3GPP TS 38.133 V15.4.0 based on the reference signal for RLM received from the non-serving cell. It suffices if it is configured as follows.

Further, according to this operation example, the UE200 (radio signal transmission / reception unit 210) is a reference signal for monitoring the quality of the radio link based on the SSB as a reference signal for RLM with the TRP of the non-serving cell. It suffices if it is configured not to send and receive.

(3.2.1.3) Operation example 1-1-3
In this operation example, as the reference signal for RLM, the reference signal for monitoring the quality of the radio link may be transmitted and received based on the SSB from the non-serving cell. Further, in this operation example, as the reference signal for RLM, the reference signal for monitoring the quality of the wireless link may be transmitted and received based on CSI-RS from the non-serving cell.

That is, according to this operation example, the UE 200 (radio signal transmission / reception unit 210) includes an information element that can identify the non-serving cell as a reference signal for RLM with the TRP of the non-serving cell, and SSB. It may be configured to send and receive a reference signal for monitoring the quality of the wireless link based on the above. Further, according to this operation example, the UE 200 (radio signal transmission / reception unit 210) can individually identify the non-serving cell in order to transmit / receive a reference signal for RLM to / from the TRP of the non-serving cell. It may be configured to send and receive setting information related to the reference signal for the RLM including the element.

Further, according to this operation example, the UE 200 (radio signal transmission / reception unit 210) includes an information element that can identify the non-serving cell as a reference signal for RLM with the TRP of the non-serving cell, and CSI. -It may be configured to send and receive reference signals to monitor the quality of the radio link based on RS.

(3.2.1.4) Operation example 1-1-4
In this operation example, when the UE200 has the ability to monitor the quality of the radio link of the non-serving cell based on the reference signal for RLM transmitted from the TRP of the non-serving cell, the TRP of the non-serving cell is used. The reference signal may be transmitted and received between the two.

Further, in this operation example, when the UE200 does not have the ability to monitor the quality of the radio link of the non-serving cell based on the reference signal for RLM transmitted from the TRP of the non-serving cell, the TRP of the non-serving cell is not provided. It suffices to prevent the reference signal from being transmitted and received to and from.

That is, according to this operation example, whether or not the UE200 (control unit 270) has the ability to monitor the quality of the radio link of the non-serving cell based on the reference signal for RLM received from the TRP of the non-serving cell. It suffices if it is configured to notify gNB100. When the UE 200 notifies the gNB 100 of the above-mentioned capability, for example, the UE capability information specified in 3GPP TS 38.306 or the like can be used.

Further, according to this operation example, the UE200 (radio signal transmission / reception unit 210) has an ability to monitor the quality of the radio link of the non-serving cell based on the reference signal for RLM received from the TRP of the non-serving cell. If so, in order to send and receive the reference signal for RLM to and from the TRP of the non-serving cell, the setting information regarding the reference signal for the RLM including the information element that can individually identify the non-serving cell is transmitted and received. It suffices if it is configured to do.

Further, according to this operation example, the UE200 (radio signal transmission / reception unit 210) has an ability to monitor the quality of the radio link of the non-serving cell based on the reference signal for RLM received from the TRP of the non-serving cell. If not, it may be configured so that the reference signal for the RLM is not transmitted / received to / from the TRP of the non-serving cell.

(3.2.1.4.1) Operation example 1-1-4-1
In this example of operation, whether the UE200 has the ability to monitor the quality of the radio link of the non-serving cell based on SSB and / or the quality of the radio link of the non-serving cell based on CSI-RS. Depending on whether the UE 200 has the ability to monitor, it may decide whether to send or receive the reference signal to and from the TRP of the non-serving cell.

That is, according to this operation example, whether or not the UE200 (control unit 270) has the ability to monitor the quality of the radio link of the non-serving cell based on the SSB, and / or to the CSI-RS. Based on this, it may be configured to notify the gNB 100 whether or not it has the ability to monitor the quality of the radio link of the non-serving cell. The above-mentioned two abilities may be notified from the UE 200 to the gNB 100 as separate abilities, or may be notified from the UE 200 to the gNB 100 as one grouped ability, for example. May be good.

Further, according to this operation example, when the UE200 (radio signal transmitter / receiver 210) has the ability to monitor the quality of the radio link of the non-serving cell based on the SSB, and / or CSI-RS. Contains information elements that can individually identify the non-serving cell in order to send and receive reference signals for RLM if it has the ability to monitor the quality of the radio link of the non-serving cell based on. It may be configured to send and receive setting information related to the reference signal for the RLM.

(3.2.2) Operation example 1-2
In this operation example, the reference signal associated with the active TCI state of the PDCCH may be transmitted and received as the reference signal for RLM between the UE 200 and the TRP of the non-serving cell. Further, in this operation example, an information element that can individually identify a non-serving cell may be added to the setting information indicating the setting regarding the active TCI state of PDCCH.

(4) Action / Effect According to the above-described embodiment, the following action / effect can be obtained.

The terminal (UE200) is a reference signal (first reference signal) for RLM transmitted from a serving cell (one of PCI # 0 and PCI # 1), and a non-serving cell (PCI # 0 and PCI # 1). The serving cell and the non. The quality of the radio link in at least one of the serving cells can be monitored. Therefore, the terminal can reduce the possibility of declaring RLF (RadioLinkFailure), and as a result, efficiently inter-cell multi-TRP / without causing unnecessary interruption, overhead and delay. You can perform panel operation.

Further, the terminal (UE200) can individually identify the non-serving cell as a reference signal (second reference signal) transmitted from the non-serving cell (the other cell of PCI # 0 and PCI # 1). Receive a reference signal containing the element. Therefore, the terminal can recognize that there are non-serving cells with better RLM results than serving cells, resulting in efficient inter-cell without incurring unnecessary interruptions, overheads and delays. You can perform multi-TRP / panel operation.

In addition, the terminal (UE200) uses SSB, CSI-RS, or theirs as a reference signal (second reference signal) transmitted from a non-serving cell (the other cell of PCI # 0 and PCI # 1). Receive a reference signal to monitor the quality of the radio link based on both. Therefore, the terminal can send and receive the reference signal for RLM to and from the non-serving cell, and as a result, efficiently inter-cell multi-TRP without causing unnecessary interruption, overhead and delay. You can perform / panel operation.

Further, the terminal (UE200) is a radio base station (gNB100) that forms a serving cell (one cell of PCI # 0 and PCI # 1) and a non-serving cell (the other cell of PCI # 0 and PCI # 1). ) Is informed whether or not it has the ability to monitor the quality of the radio link of the non-serving cell based on the reference signal (second reference signal) transmitted from the non-serving cell. Therefore, the terminal can send and receive a reference signal for RLM to and from the non-serving cell only if it has the ability to monitor the quality of the radio link of the non-serving cell, and as a result, it is unnecessary. It is possible to efficiently perform inter-cell multi-TRP / panel operation without causing any interruption, overhead and delay.

Further, the terminal (UE200) has the same symbol or at least one symbol before and after the resource of the reference signal (second reference signal) received from the non-serving cell (the other cell of PCI # 0 and PCI # 1) or its own. In both cases, it can be assumed that transmission to or reception from the serving cell (one of PCI # 0 and PCI # 1) is not performed. Therefore, the terminal can reliably receive the reference signal transmitted from the non-serving cell.

(5) Other Embodiments Although the embodiments have been described above, it is obvious to those skilled in the art that various modifications and improvements are possible without limitation to the description of the embodiments.

Further, the block configuration diagram (FIG. 3) used in the description of the above-described embodiment shows a block of functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Further, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one physically or logically coupled device, or two or more physically or logically separated devices can be directly or indirectly (eg, for example). , Wired, wireless, etc.) and may be realized using these plurality of devices. The functional block may be realized by combining the software with the one device or the plurality of devices.

Functions include judgment, decision, judgment, calculation, calculation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, solution, selection, selection, establishment, comparison, assumption, expectation, and assumption. Broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, assigning, etc., but limited to these I can't. For example, a functional block (configuration unit) that makes transmission function is called a transmitting unit (transmitting unit) or a transmitter (transmitter). In each case, as described above, the realization method is not particularly limited.

Further, the above-mentioned UE200 (the device) may function as a computer that processes the wireless communication method of the present disclosure. FIG. 6 is a diagram showing an example of the hardware configuration of the device. As shown in FIG. 6, the device may be configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.

In the following explanation, the word "device" can be read as a circuit, device, unit, etc. The hardware configuration of the device may be configured to include one or more of each of the devices shown in the figure, or may be configured not to include some of the devices.

Each functional block of the device (see FIG. 3) is realized by any hardware element of the computer device or a combination of the hardware elements.

In addition, for each function in the device, the processor 1001 performs calculations by loading predetermined software (program) on the hardware such as the processor 1001 and the memory 1002, and controls the communication by the communication device 1004, or the memory. It is realized by controlling at least one of reading and writing of data in 1002 and storage 1003.

Processor 1001 operates, for example, an operating system to control the entire computer. The processor 1001 may be configured by a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, and the like.

Further, the processor 1001 reads a program (program code), a software module, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least a part of the operations described in the above-described embodiment is used. Further, the various processes described above may be executed by one processor 1001 or may be executed simultaneously or sequentially by two or more processors 1001. Processor 1001 may be implemented by one or more chips. The program may be transmitted from the network via a telecommunication line.

The memory 1002 is a computer-readable recording medium, and is composed of at least one such as ReadOnlyMemory (ROM), ErasableProgrammableROM (EPROM), Electrically ErasableProgrammableROM (EEPROM), and RandomAccessMemory (RAM). May be done. The memory 1002 may be referred to as a register, a cache, a main memory (main storage device), or the like. The memory 1002 can store a program (program code), a software module, or the like that can execute the method according to the embodiment of the present disclosure.

The storage 1003 is a computer-readable recording medium, for example, an optical disk such as Compact Disc ROM (CD-ROM), a hard disk drive, a flexible disk, an optical magnetic disk (for example, a compact disk, a digital versatile disk, or a Blu-ray). It may consist of at least one (registered trademark) disk), smart card, flash memory (eg, card, stick, key drive), floppy (registered trademark) disk, magnetic strip, and the like. Storage 1003 may be referred to as auxiliary storage. The recording medium described above may be, for example, a database, server or other suitable medium containing at least one of the memory 1002 and the storage 1003.

The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, or the like.

The communication device 1004 includes, for example, a high frequency switch, a duplexer, a filter, a frequency synthesizer, etc. in order to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). It may be composed of.

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts an input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may have an integrated configuration (for example, a touch panel).

In addition, each device such as the processor 1001 and the memory 1002 is connected by the bus 1007 for communicating information. Bus 1007 may be configured using a single bus or may be configured using different buses for each device.

Furthermore, the device includes hardware such as a microprocessor, a digital signal processor (Digital Signal Processor: DSP), an ApplicationSpecific Integrated Circuit (ASIC), a ProgrammableLogicDevice (PLD), and a FieldProgrammableGateArray (FPGA). The hardware may implement some or all of each functional block. For example, processor 1001 may be implemented using at least one of these hardware.

Further, the notification of information is not limited to the embodiment / embodiment described in the present disclosure, and may be performed by using another method. For example, information notification includes physical layer signaling (eg Downlink Control Information (DCI), Uplink Control Information (UCI), higher layer signaling (eg RRC signaling, Medium Access Control (MAC) signaling, Master Information Block). (MIB), System Information Block (SIB)), other signals or combinations thereof. RRC signaling may also be referred to as an RRC message, eg, RRC Connection Setup. ) Message, RRC Connection Reconfiguration message, etc. may be used.

Each aspect / embodiment described in the present disclosure includes Long Term Evolution (LTE), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4th generation mobile communication system ( ^4G ), 5th generation mobile communication system. (5G), Future Radio Access (FRA), New Radio (NR), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)) ), IEEE 802.16 (WiMAX®), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth®, and other systems that utilize appropriate systems and at least next-generation systems extended based on them. It may be applied to one. In addition, a plurality of systems may be applied in combination (for example, a combination of at least one of LTE and LTE-A and 5G).

The order of the processing procedures, sequences, flowcharts, etc. of each aspect / embodiment described in the present disclosure may be changed as long as there is no contradiction. For example, the methods described in the present disclosure present elements of various steps using exemplary order, and are not limited to the particular order presented.

In some cases, the specific operation performed by the base station in this disclosure may be performed by its upper node (upper node). In a network consisting of one or more network nodes having a base station, various operations performed for communication with the terminal are the base station and other network nodes other than the base station (eg, MME or). It is clear that it can be done by at least one of (but not limited to, S-GW, etc.). Although the case where there is one network node other than the base station is illustrated above, it may be a combination of a plurality of other network nodes (for example, MME and S-GW).

Information and signals (information, etc.) can be output from the upper layer (or lower layer) to the lower layer (or upper layer). Input / output may be performed via a plurality of network nodes.

The input / output information may be stored in a specific location (for example, memory) or may be managed using a management table. I / O information can be overwritten, updated, or added. The output information may be deleted. The entered information may be transmitted to other devices.

The determination may be made by a value represented by 1 bit (0 or 1), by a boolean value (Boolean: true or false), or by comparing numerical values (for example, a predetermined value). It may be done by comparison with the value).

Each aspect / embodiment described in the present disclosure may be used alone, in combination, or may be switched and used according to the execution. Further, the notification of predetermined information (for example, the notification of "being X") is not limited to the explicit one, but is performed implicitly (for example, the notification of the predetermined information is not performed). May be good.

Software, whether called software, firmware, middleware, microcode, hardware description language, or other names, instructions, instruction sets, codes, code segments, program codes, programs, subprograms, software modules. , Applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, features, etc. should be broadly interpreted.

Further, software, instructions, information, etc. may be transmitted and received via a transmission medium. For example, a website, where the software uses at least one of wired technology (coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), etc.) and wireless technology (infrared, microwave, etc.). When transmitted from a server or other remote source, at least one of these wired and wireless technologies is included within the definition of transmission medium.

The information, signals, etc. described in this disclosure may be represented using any of a variety of different techniques. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description are voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any of these. It may be represented by a combination of.

The terms described in the present disclosure and the terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Also, the signal may be a message. Further, the component carrier (CC) may be referred to as a carrier frequency, a cell, a frequency carrier, or the like.

The terms "system" and "network" used in this disclosure are used interchangeably.

Further, the information, parameters, etc. described in the present disclosure may be expressed using an absolute value, a relative value from a predetermined value, or another corresponding information. It may be represented. For example, the radio resource may be one indicated by an index.

The names used for the above parameters are not limited in any respect. Further, mathematical formulas and the like using these parameters may differ from those expressly disclosed in this disclosure. Since various channels (eg, PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, the various names assigned to these various channels and information elements are in any respect limited names. is not.

In this disclosure, "Base Station (BS)", "Wireless Base Station", "Fixed Station", "NodeB", "eNodeB (eNB)", "gNodeB (gNB)", " "Access point", "transmission point", "reception point", "transmission / reception point", "cell", "sector", "cell group", " Terms such as "carrier" and "component carrier" may be used interchangeably. Base stations are sometimes referred to by terms such as macrocells, small cells, femtocells, and picocells.

A base station can accommodate one or more (eg, three) cells (also called sectors). When a base station accommodates multiple cells, the entire base station coverage area can be divided into multiple smaller areas, each smaller area being a base station subsystem (eg, a remote radio for indoor use). Communication services can also be provided by Head: RRH).

The term "cell" or "sector" refers to a base station that provides communication services in this coverage, and part or all of the coverage area of at least one of the base station subsystems.

In the present disclosure, terms such as "Mobile Station (MS)", "user terminal", "user equipment (UE)", and "terminal" may be used interchangeably. ..

Mobile stations can be used by those skilled in the art as subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals, mobile terminals, wireless. It may also be referred to as a terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable term.

At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, or the like. At least one of the base station and the mobile station may be a device mounted on the mobile body, a mobile body itself, or the like. The moving body may be a vehicle (eg, car, airplane, etc.), an unmanned moving body (eg, drone, self-driving car, etc.), or a robot (manned or unmanned). ) May be. It should be noted that at least one of the base station and the mobile station includes a device that does not necessarily move during communication operation. For example, at least one of a base station and a mobile station may be an Internet of Things (IoT) device such as a sensor.

Further, the base station in the present disclosure may be read as a mobile station (user terminal, the same shall apply hereinafter). For example, communication between a base station and a mobile station has been replaced with communication between a plurality of mobile stations (for example, it may be called Device-to-Device (D2D), Vehicle-to-Everything (V2X), etc.). Each aspect / embodiment of the present disclosure may be applied to the configuration. In this case, the mobile station may have the functions of the base station. Further, the words such as "up" and "down" may be read as words corresponding to the communication between terminals (for example, "side"). For example, the upstream channel, the downstream channel, and the like may be read as a side channel.

Similarly, the mobile station in the present disclosure may be read as a base station. In this case, the base station may have the functions of the mobile station.

The wireless frame may be composed of one or more frames in the time domain. Each one or more frames in the time domain may be referred to as a subframe. Subframes may further be composed of one or more slots in the time domain. The subframe may have a fixed time length (eg, 1 ms) that does not depend on numerology.

The numerology may be a communication parameter that applies to at least one of the transmission and reception of a signal or channel. Numerology includes, for example, SubCarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (Transmission Time Interval: TTI), number of symbols per TTI, wireless frame configuration, transmission / reception. It may indicate at least one of a specific filtering process performed by the machine in the frequency domain, a specific windowing process performed by the transmitter / receiver in the time domain, and the like.

The slot may be composed of one or more symbols (Orthogonal Frequency Division Multiplexing (OFDM) symbol, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol, etc.) in the time area. The slot may be a unit of time based on numerology.

The slot may include a plurality of mini slots. Each minislot may be composed of one or more symbols in the time domain. Further, the mini slot may be referred to as a sub slot. The minislot may consist of a smaller number of symbols than the slot. PDSCH (or PUSCH) transmitted in time units larger than the minislot may be referred to as PDSCH (or PUSCH) mapping type A. The PDSCH (or PUSCH) transmitted using the minislot may be referred to as PDSCH (or PUSCH) mapping type B.

The wireless frame, subframe, slot, minislot and symbol all represent the time unit when transmitting a signal. The radio frame, subframe, slot, minislot and symbol may have different names corresponding to each.

For example, one subframe may be referred to as a transmission time interval (TTI), a plurality of consecutive subframes may be referred to as TTI, and one slot or one minislot may be referred to as TTI. That is, at least one of the subframe and TTI may be a subframe (1ms) in existing LTE, a period shorter than 1ms (eg, 1-13 symbols), or a period longer than 1ms. May be. The unit representing TTI may be called a slot, a mini slot, or the like instead of a subframe.

Here, TTI refers to, for example, the minimum time unit of scheduling in wireless communication. For example, in an LTE system, a base station schedules each user terminal to allocate radio resources (frequency bandwidth that can be used in each user terminal, transmission power, etc.) in TTI units. The definition of TTI is not limited to this.

TTI may be a transmission time unit such as a channel-encoded data packet (transport block), a code block, or a code word, or may be a processing unit such as scheduling or link adaptation. When a TTI is given, the time interval (for example, the number of symbols) to which the transport block, code block, code word, etc. are actually mapped may be shorter than the TTI.

When one slot or one mini slot is called TTI, one or more TTIs (that is, one or more slots or one or more mini slots) may be the minimum time unit for scheduling. Further, the number of slots (number of mini-slots) constituting the minimum time unit of the scheduling may be controlled.

TTI with a time length of 1 ms may be called normal TTI (TTI in LTE Rel.8-12), normal TTI, long TTI, normal subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a normal TTI may be referred to as a shortened TTI, a short TTI, a partial TTI (partial or fractional TTI), a shortened subframe, a short subframe, a minislot, a subslot, a slot, and the like.

The long TTI (for example, normal TTI, subframe, etc.) may be read as a TTI having a time length of more than 1 ms, and the short TTI (for example, shortened TTI, etc.) may be read as a TTI less than the TTI length of the long TTI and 1 ms. It may be read as a TTI having the above TTI length.

The resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or a plurality of continuous subcarriers in the frequency domain. The number of subcarriers contained in RB may be the same regardless of numerology, and may be, for example, 12. The number of subcarriers contained in the RB may be determined based on numerology.

Further, the time domain of RB may include one or more symbols, and may have a length of 1 slot, 1 mini slot, 1 subframe, or 1 TTI. Each 1TTI, 1 subframe, etc. may be composed of one or a plurality of resource blocks.

One or more RBs are physical resource blocks (Physical RB: PRB), sub-carrier groups (Sub-Carrier Group: SCG), resource element groups (Resource Element Group: REG), PRB pairs, RB pairs, etc. May be called.

Further, the resource block may be composed of one or a plurality of resource elements (ResourceElement: RE). For example, 1RE may be a radio resource area of 1 subcarrier and 1 symbol.

Bandwidth Part (BWP) (which may also be called partial bandwidth, etc.) may represent a subset of consecutive common resource blocks (RBs) for a neurology in a carrier. good. Here, the common RB may be specified by the index of the RB with respect to the common reference point of the carrier. PRBs may be defined in a BWP and numbered within that BWP.

BWP may include BWP for UL (UL BWP) and BWP for DL (DL BWP). One or more BWPs may be set in one carrier for the UE.

At least one of the configured BWPs may be active, and the UE may not expect to send or receive a given signal / channel outside the active BWP. In addition, "cell", "carrier" and the like in this disclosure may be read as "BWP".

The above-mentioned structures such as wireless frames, subframes, slots, mini-slots and symbols are merely examples. For example, the number of subframes contained in a wireless frame, the number of slots per subframe or wireless frame, the number of minislots contained within a slot, the number of symbols and RBs contained in a slot or minislot, included in RB. The number of subcarriers, as well as the number of symbols in the TTI, the symbol length, the cyclic prefix (CP) length, and other configurations can be changed in various ways.

The terms "connected", "coupled", or any variation thereof, mean any direct or indirect connection or connection between two or more elements and each other. It can include the presence of one or more intermediate elements between two "connected" or "joined" elements. The connection or connection between the elements may be physical, logical, or a combination thereof. For example, "connection" may be read as "access". As used in the present disclosure, the two elements use at least one of one or more wires, cables and printed electrical connections, and, as some non-limiting and non-comprehensive examples, the radio frequency domain. Can be considered to be "connected" or "coupled" to each other using electromagnetic energy having wavelengths in the microwave and light (both visible and invisible) regions.

The reference signal can also be abbreviated as Reference Signal (RS), and may be called a pilot (Pilot) depending on the applied standard.

The statement "based on" used in this disclosure does not mean "based on" unless otherwise stated. In other words, the statement "based on" means both "based only" and "at least based on".

The "means" in the configuration of each of the above devices may be replaced with a "part", a "circuit", a "device", or the like.

Any reference to elements using designations such as "first" and "second" as used in this disclosure does not generally limit the quantity or order of those elements. These designations can be used in the present disclosure as a convenient way to distinguish between two or more elements. Therefore, references to the first and second elements do not mean that only two elements can be adopted there, or that the first element must somehow precede the second element.

When "include", "including" and variations thereof are used in the present disclosure, these terms are as inclusive as the term "comprising". Is intended. Moreover, the term "or" used in the present disclosure is intended to be non-exclusive.

In the present disclosure, if articles are added by translation, for example, a, an and the in English, the disclosure may include the plural nouns following these articles.

The terms "determining" and "determining" used in this disclosure may include a wide variety of actions. "Judgment" and "decision" are, for example, judgment (judging), calculation (calculating), calculation (computing), processing (processing), derivation (deriving), investigation (investigating), search (looking up, search, inquiry). It may include (eg, searching in a table, database or another data structure), ascertaining as "judgment" or "decision". Also, "judgment" and "decision" are receiving (for example, receiving information), transmitting (for example, transmitting information), input (input), output (output), and access. It may include (for example, accessing data in memory) to be regarded as "judgment" or "decision". In addition, "judgment" and "decision" are considered to be "judgment" and "decision" when the things such as solving, selecting, choosing, establishing, and comparing are regarded as "judgment" and "decision". Can include. That is, "judgment" and "decision" may include considering some action as "judgment" and "decision". Further, "judgment (decision)" may be read as "assuming", "expecting", "considering" and the like.

In the present disclosure, the term "A and B are different" may mean "A and B are different from each other". The term may mean that "A and B are different from C". Terms such as "separate" and "combined" may be interpreted in the same way as "different".

Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure may be implemented as amendments and modifications without departing from the spirit and scope of the present disclosure as determined by the description of the scope of claims. Therefore, the description of this disclosure is for purposes of illustration and does not have any limiting meaning to this disclosure.

10 Radio communication system 20 NG-RAN
100 Radio Base Station (gNB)
200 UE
210 Wireless signal transmitter / receiver 220 Amplifier 230 Modulator / demodulator 240 Control signal / reference signal processing 250 Encoding / decoding 260 Data transmitter / receiver 270 Control 1001 Processor 1002 Memory 1003 Storage 1004 Communication device 1005 Input device 1006 Output device 1007 Bus

Claims

A receiver that receives at least one reference signal among the first reference signal transmitted from the serving cell and the second reference signal transmitted from the non-serving cell.
A control unit that monitors the quality of the radio link in at least one of the serving cell and the non-serving cell based on the at least one reference signal received by the receiving unit.
A terminal equipped with.
The terminal according to claim 1.
The receiving unit receives setting information regarding the second reference signal including an information element that can individually identify the non-serving cell.
The terminal according to claim 2.
The second reference signal is a reference signal for monitoring the quality of the radio link based on the SSB (SS / PBCH Block).
The terminal according to claim 2.
The control unit notifies the serving cell and the radio base station forming the non-serving cell whether or not it has the ability to monitor the quality of the radio link of the non-serving cell based on the second reference signal. do.
The terminal according to claim 1.
The control unit does not transmit to or receive from the serving cell with the resource of the second reference signal received from the non-serving cell and / or at least one symbol before and after the same symbol. Suppose.
A step of receiving at least one reference signal of a first reference signal transmitted from a serving cell and a second reference signal transmitted from a non-serving cell.
A step of monitoring the quality of the radio link in at least one of the serving cell and the non-serving cell based on the at least one reference signal.
A wireless communication method.