Beam management during satellite handover with resynchronization

Abstract

To enable channel monitoring, the user equipment (UE) receives a quasi-co-location (QCL) configuration (1901) in the serving cell for monitoring channels in a target cell that has the same cell identifier as the serving cell; receives an indication in the serving cell of a time related to a change in coverage of at least one of the serving cell or the target cell (1905); and begins monitoring of channels in the target cell according to the QCL configuration and at the indicated time (1965).

Description

[0001] Citation of relevant applications

[0002] This application claims priority and benefit to Provisional U.S. Patent Application No. 63 / 616,616, filed December 30, 2023, entitled “Beam Management During Satellite Switch with Resynchronization”. The entire contents of that provisional application are hereby expressly incorporated herein by reference. Technical Field

[0003] This disclosure relates generally to wireless communications, and more specifically to improving handover between non-terrestrial network (NTN) cells at the user equipment (UE). Background Technology

[0004] This background description is provided for the purpose of presenting the general context of this disclosure. The work of the currently attributed inventors (to the extent described in this background section) and aspects of the specification that might not have been considered prior art at the time of filing are neither expressly nor impliedly acknowledged as prior art relative to this disclosure.

[0005] The goals behind the development of fifth-generation (5G) technology include providing a unified framework for communication types such as enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC), and massive machine-type communication (mMTC).

[0006] 5G technology primarily relies on legacy terrestrial networks. However, the 3rd Generation Partnership Project (3GPP) has proposed extending 5G communications to non-terrestrial networks (NTNs) using either 5G New Radio (NR) technology or Long Term Evolution (LTE) technology tailored for narrowband Internet of Things (NB-IoT) or enhanced machine-type communications (eMTC) scenarios. In an NTN, RF transceivers are mounted on satellites, unmanned aerial vehicle systems (UAS) (such as drones, balloons, or airplanes), or other suitable equipment. For simplicity, the following discussion will refer to all such equipment as satellites. In addition to satellites, an NTN may also include satellite gateways connecting non-terrestrial networks to public data networks, feeder links between satellite gateways and satellites, service links between satellites, and inter-satellite links (ISLs) when satellites form a constellation.

[0007] Satellites can be classified into several types based on their altitude, orbit, and footprint size. These types include low Earth orbit (LEO) satellites, medium Earth orbit (LEO) satellites, geostationary orbit (GEO) satellites, UAS platform satellites (including High Altitude Platform Stations (HAPS), and highly elliptical orbit (HEO) satellites. GEO satellites are also known as geosynchronous orbit (GSO) satellites, and LEO / MEO satellites are also known as non-GSO (NGSO) satellites.

[0008] GSO satellites can communicate with one or more satellite gateways deployed over the satellite's target coverage area (e.g., a region or even a continent). Non-GSO satellites can communicate with one or more serving satellite gateways at different times. NTN is designed to ensure service and feeder link continuity between connected serving satellite gateways, while having sufficient duration for mobility anchoring and handover.

[0009] Satellites can support transparent or regenerative (with onboard processing) payloads and typically generate several beams for a given service area defined by a field of view. The coverage area of ​​the beams is usually elliptical in shape and depends on the onboard antenna configuration and elevation angle. For transparent payload implementations, satellites can apply RF filtering, frequency conversion, and amplification without altering the waveform signal. For regenerative payload implementations, satellites can apply RF filtering, frequency conversion and amplification, demodulation and decoding, routing, and encoding / decoding / modulation. This approach effectively implements most of the functions of a base station (e.g., a gNB).

[0010] In these and other scenarios, due to rapid satellite movement, a large number of UEs may need to frequently perform handovers from one cell to another. To mitigate the impact of long service interruptions and signaling overhead caused by these types of handovers, different satellites can use the same Physical Cell Identifier (PCI) when serving / covering the same geographical area. This prevents UEs from triggering handover processes due to changes in the serving link (i.e., the link between the satellite and the UE).

[0011] However, although the same PCI method creates the effect of the UE receiving service from the same cell after switching to a new satellite, the UE still needs to resynchronize and align with the new beam provided by the new satellite. Performing beam alignment after switching to a new satellite can significantly disrupt service continuity and may even trigger a random access procedure (which further exacerbates the service continuity disruption). Therefore, it is desirable to make beam alignment more efficient in these scenarios. Summary of the Invention

[0012] Generally speaking, the technology disclosed herein allows connected UEs to hand over between cells that share the same identifier, such as PCI, with minimal service interruption time.

[0013] Example embodiments of these technologies are channel monitoring methods implemented in user equipment (UE). The method includes: receiving a quasi-co-location (QCL) configuration in the serving cell for monitoring channels in a target cell having the same cell identifier as the serving cell; receiving an indication in the serving cell of a time relating to a change in coverage of at least one of the serving cell or the target cell; and initiating monitoring of the channels in the target cell according to the QCL configuration and at the indicated time.

[0014] Another example embodiment of these technologies is a configuration method implemented in a radio access network (RAN) node. The method includes: transmitting, in the serving cell of the UE, an indication of time relating to a change in coverage of at least one of (a) the serving cell or (b) a target cell having the same cell identifier as the serving cell; and transmitting, in the serving cell, a quasi-co-address (QCL) configuration for monitoring channels in the target cell, the QCL configuration being based on a determination of which reference signal of the UE in the target cell is quasi-co-addressed with the transmission on the channel.

[0015] Another example embodiment of these technologies is an apparatus that includes a transceiver and is configured to implement one of the methods described above. Attached Figure Description

[0016] Figure 1A This is a block diagram of an example wireless communication system in which user equipment and base stations associated with NTN can implement the beam management technology of this disclosure;

[0017] Figure 1B Among them, centralized units (CU) and distributed units (DU) can be Figure 1A A block diagram of an example base station operating in the system;

[0018] Figure 2A This is a block diagram of an example protocol stack. Figure 1A The UE communicates with the base station according to this protocol stack;

[0019] Figure 2B This is a block diagram of an example protocol stack. Figure 1A The UE communicates with the CU and DU according to this protocol stack;

[0020] Figure 3A This is a block diagram of an example NTN node with a transparent payload implementation.

[0021] Figure 3BThis is a block diagram of an example NTN node with a transparent payload implementation where the base station is connected to multiple satellites via the same satellite gateway;

[0022] Figure 4A It shows the use of with Figure 3A An exemplary user plane protocol stack used in conjunction with the architecture;

[0023] Figure 4B It shows the use of with Figure 3A An exemplary control plane protocol stack used in conjunction with the architecture;

[0024] Figure 5 This is a block diagram illustrating an example scenario in which a stationary UE uses a resynchronization process to switch from one satellite to another without performing a handover (HO) process;

[0025] Figure 6 This is a message passing diagram of an example scenario in which a UE in the connected state receives a TCI state activation indication shortly before a satellite handover with resynchronization occurs;

[0026] Figure 7 This is a message passing diagram of an example scenario in which a UE in a connected state receives a PDCCH configuration including a deactivated TCI identifier and activates the deactivated TCI identifier shortly before a satellite handover with resynchronization occurs.

[0027] Figure 8 This is a message passing diagram of an example scenario in which a UE in the connected state receives a PDSCH configuration including a deactivated TCI state and activates one of the deactivated TCI states shortly before a satellite handover with resynchronization occurs.

[0028] Figure 9 This is a message passing diagram of an example scenario in which a UE in a connected state receives a CSI measurement configuration including deactivated CSI-RS resources and activates the CSI-RS resources before a satellite handover with resynchronization occurs.

[0029] Figure 10 This is a message passing diagram of an example scenario in which a connected UE receives and facilitates the monitoring of the SSB index or SSB time offset value of the PDCCH at the UE after a satellite handover with resynchronization.

[0030] Figure 11 This is a flowchart of an example method that can be implemented in a connected UE to activate the TCI state for PDCCH monitoring when downlink control information is received;

[0031] Figure 12This is a flowchart of an example method that can be implemented in a connected UE for receiving a PDCCH configuration including a deactivated TCI status identifier and determining when to activate the deactivated TCI status identifier.

[0032] Figure 13 This is a flowchart of an example method that can be implemented in a connected UE for receiving a PDSCH configuration including a deactivated TCI state and determining when to activate the deactivated TCI state.

[0033] Figure 14 This is a flowchart of an example method that can be implemented in a connected UE for receiving a CSI measurement configuration including deactivated CSI RS resources and determining when to activate the deactivated CSI RS resources;

[0034] Figure 15 This is a flowchart of an example method for receiving an SSB index or SSB time offset that can be implemented in a connected UE after a satellite handover with resynchronization.

[0035] Figure 16 This is a flowchart of an example method that can be implemented in a BS to activate the TCI state for PDCCH monitoring in a satellite switch with a resynchronization process;

[0036] Figure 17A This is a flowchart of an example method that can be implemented in the BS for configuring a deactivated TCI status flag in the PDCCH configuration to be activated during or after satellite handover with a resynchronization process;

[0037] Figure 17B This is a flowchart of an example method that can be implemented in BS for configuring a deactivated TCI state in the PDSCH configuration to be activated during or after satellite handover with a resynchronization process;

[0038] Figure 17C This is a flowchart of an example method that can be implemented in a BS for configuring deactivated CSI-RS resources in a CSI measurement configuration to be activated during or after satellite handover with a resynchronization process;

[0039] Figure 18 This is a flowchart of an example method that can be implemented in the BS for configuring the SSB index or SSB time offset applicable to the UE after a satellite handover with resynchronization.

[0040] Figure 19 This is a flowchart of an example channel monitoring method in a UE; and

[0041] Figure 20This is a flowchart of an example configuration method in a RAN node. Detailed Implementation

[0042] As discussed in more detail below, user equipment (UE) and / or network nodes of a radio access network (RAN) can use the techniques disclosed herein to perform beam management during synchronized handover between NTN (e.g., satellite) cells.

[0043] First refer to Figure 1A Example wireless communication system 100 includes UE 102, base station (BS) 104, base station 106, and core network (CN) 110. Base stations 104 and 106 can operate in RAN 105 connected to core network (CN) 110. CN 110 can be implemented as, for example, an evolved packet core (EPC) 111 or a fifth-generation (5G) core (5GC) 160. In another example, CN 110 can also be implemented as a sixth-generation (6G) core.

[0044] Base station 104 covers cells 124 and 125, and base station 106 covers cell 126. In the NTN implementation, cells 124 and 125 may correspond to different satellites but share the same cell identifier. If base station 104 is a gNB, then cell 124 is an NR cell. If base station 104 is an ng-eNB or eNB, then cell 124 is an Evolved Universal Terrestrial Radio Access (E-UTRA) cell. Similarly, if base station 106 is a gNB, then cell 126 is an NR cell, and if base station 106 is an ng-eNB or eNB, then cell 126 is an E-UTRA cell. Cells 124 and 126 may be located in the same Radio Access Network Notification Area (RNA) or different RNAs. Generally, RAN 105 may include any number of base stations, and each base station may cover one, two, three, or any other suitable number of cells. UE 102 may support at least 5G NR (or simply "NR") or E-UTRA air interface to communicate with base stations 104 and 106. Each of base stations 104 and 106 may be connected to CN 110 via an interface (e.g., S1 or NG interface). Base stations 104 and 106 may also be interconnected via an interface for interconnecting NG RAN nodes (e.g., X2 or Xn interface).

[0045] Among other components, EPC 111 may include a Serving Gateway (SGW) 112, a Mobility Management Entity (MME) 114, and a Packet Data Network Gateway (PGW) 116. SGW 112 is generally configured to deliver user plane packets related to audio calls, video calls, Internet traffic, etc., and MME 114 is configured to manage authentication, registration, paging, and other related functions. PGW 116 provides connectivity from the UE to one or more external packet data networks (e.g., Internet networks and / or Internet Protocol (IP) Multimedia Subsystem (IMS) networks). 5GC 160 includes User Plane Functions (UPF) 162, Access and Mobility Management Functions (AMF) 164, and / or Session Management Functions (SMF) 166. Generally, UPF 162 is configured to deliver user plane packets related to audio calls, video calls, Internet traffic, etc., AMF 164 is configured to manage authentication, registration, paging and other related functions, and SMF 166 is configured to manage PDU sessions.

[0046] like Figure 1A As shown, base station 104 supports cell 124, and base station 106 supports cell 126. Cells 124 and 126 may partially overlap, allowing UE 102 to select, reselect, or switch from one cell to another. For direct message or information exchange, base stations 104 and 106 may support X2 or Xn interfaces. Generally, CN 110 can connect to any suitable number of base stations supporting NR cells and / or EUTRA cells.

[0047] As discussed in detail below, when the radio connection between UE 102 and RAN 105 is suspended, for example, when UE 102 is operating in an inactive or idle state of the protocol used to control the radio resources between UE 102 and RAN 105, UE 102 and / or RAN 105 can utilize the techniques of this disclosure. For clarity, the examples below refer to the RRC_INACTIVE or RRC_IDLE states of the RRC protocol.

[0048] Base station 104 is equipped with processing hardware 130, which may include one or more general-purpose processors (e.g., CPUs) and a non-transitory computer-readable storage device storing instructions executed by the one or more general-purpose processors. Alternatively, processing hardware 130 may include dedicated processing units. In an example implementation, processing hardware 130 includes a processor 132 to process data that base station 104 will transmit in the downlink direction or to process data received by base station 104 in the uplink direction. Processing hardware 130 may also include a transmitter 136 configured to transmit data in the downlink direction. The processing hardware may further include a receiver 134 configured to receive data in the uplink direction. Base station 106 may include substantially similar components. Specifically, components 140, 142, 144, and 146 of base station 106 may be similar to components 130, 132, 134, and 136, respectively.

[0049] UE 102 is equipped with processing hardware 150, which may include one or more general-purpose processors (such as a CPU) and a non-transitory computer-readable memory storing machine-readable instructions executable on the one or more general-purpose processors, and / or dedicated processing units. In an example implementation, processing hardware 150 includes a processor 152 to process data that UE 102 will transmit in the uplink direction, or to process data received by UE 102 in the downlink direction. Processing hardware 150 may also include a transmitter 156 configured to transmit data in the downlink direction. The processing hardware may further include a receiver 154 configured to receive data in the uplink direction.

[0050] Figure 1B Example distributed or decomposed implementations of any one or more of base stations 104 and 106 are depicted. In this implementation, base stations 104 and 106 include a central unit (CU) 172 and one or more distributed units (DUs) 174. CU 172 includes processing hardware, such as one or more general-purpose processors (e.g., CPUs) and computer-readable memory storing machine-readable instructions executable on the general-purpose processor, and / or dedicated processing units. For example, CU 172 may include a PDCP controller, an RRC controller, and / or an RRC inactivity controller. In some implementations, CU 172 may include a radio link control (RLC) controller configured to manage or control one or more RLC operations or processes. In further implementations, CU 172 does not include an RLC controller.

[0051] Each DU in DU 174 also includes processing hardware, which may include one or more general-purpose processors (e.g., CPUs) and computer-readable memory storing machine-readable instructions executable on the one or more general-purpose processors, and / or dedicated processing units. For example, the processing hardware may include: a MAC controller configured to manage or control one or more MAC operations or procedures (e.g., random access procedures); and / or an RLC controller configured to manage or control one or more RLC operations or procedures. The processing hardware may also include a physical layer controller configured to manage or control one or more physical layer operations or procedures.

[0052] In some embodiments, RAN 105 supports Integrated Access and Backhaul (IAB) functionality. In some implementations, DU 174 operates as an IAB node, and CU 172 operates as an IAB donor. In some embodiments, RAN 105 supports Non-Terrestrial Network (NTN) functionality.

[0053] In some implementations, CU 172 may include a logical node CU-CP 172A that hosts the control plane portion of the PDCP protocol for CU 172. CU 172 may also include a logical node CU-UP 172B that hosts the user plane portion of the PDCP protocol and / or the Service Data Adaptation Protocol (SDAP) protocol for CU 172. CU-CP 172A may transmit control information (e.g., RRC messages, F1 application protocol messages), and CU-UP 172B may transmit data packets (e.g., SDAP PDUs or Internet Protocol packets).

[0054] A CU-CP 172A can connect to multiple CU-UP 172Bs via an E1 interface. The CU-CP 172A selects the appropriate CU-UP 172B for the service requested by UE 102. In some implementations, a single CU-UP 172B can connect to multiple CU-CP 172As via an E1 interface. A CU-CP 172A can connect to one or more DU 174s via an F1-C interface. A CU-UP 172B can connect to one or more DU 174s via an F1-U interface under the control of the same CU-CP 172A. In some implementations, a DU 174 can connect to multiple CU-UP 172Bs under the control of the same CU-CP 172A. In such implementations, the connectivity between the CU-UP 172B and DU 174 is established by the CU-CP 172A using bearer context management functions.

[0055] Figure 2AAn example protocol stack 200 is shown in a simplified manner, which UE 102 can use to communicate with an eNB / ng-eNB or gNB (e.g., one or more of base stations 104, 106).

[0056] In example stack 200, the EUTRA physical layer (PHY) 202A provides a transport channel to the EUTRA MAC sublayer 204A, which in turn provides a logical channel to the EUTRA RLC sublayer 206A. The EUTRA RLC sublayer 206A then provides an RLC channel to the EUTRA PDCP sublayer 208 and, in some cases, to the NR PDCP sublayer 210. Similarly, the NRPHY 202B provides a transport channel to the NR MAC sublayer 204B, which in turn provides a logical channel to the NR RLC sublayer 206B. The NR RLC sublayer 206B then provides data delivery services to the NR PDCP sublayer 210. The NR PDCP sublayer 210 can then provide data delivery services to the Serving Data Adaptation Protocol (SDAP) 212 or the Radio Resource Control (RRC) sublayer. Figure 2A (Not shown in the image) provides data transfer services. In some implementations, UE 102 supports both EUTRA and NR stacks, such as... Figure 2A As shown, this supports handover between EUTRA and NR base stations and / or supports DCs via EUTRA and NR interfaces. Further, as... Figure 2A As shown, UE102 can support the layering of NR PDCP 210 on EUTRA RLC 206A, and the layering of SDAP sublayer 212 on NR PDCP sublayer 210.

[0057] EUTRA PDCP sublayer 208 and NR PDCP sublayer 210 (e.g., from an Internet Protocol (IP) layer layered directly or indirectly on PDCP layers 208 or 210) receive packets that can be referred to as Service Data Units (SDUs), and (e.g., to RLC layers 206A or 206B) output packets that can be referred to as Protocol Data Units (PDUs). For simplicity, except where the difference between SDU and PDU is relevant, this disclosure refers to both SDU and PDU as "packets".

[0058] On the control plane, EUTRA PDCP sublayer 208 and NR PDCP sublayer 210 can provide signaling radio bearer (SRB) or RRC sublayer ( Figure 2A(Not shown) to exchange, for example, RRC messages or Non-Access Stratum (NAS) messages. On the user plane, EUTRA PDCP sublayer 208 and NR PDCP sublayer 210 can provide data radio bearers (DRBs) to support data exchange. The data exchanged on NR PDCP sublayer 210 can be SDAP PDUs, Internet Protocol (IP) packets, or Ethernet packets.

[0059] Figure 2B An example protocol stack 250 is shown in a simplified manner, illustrating how UE 102 can communicate with DU (e.g., DU 174) and CU (e.g., CU 172). The radio protocol stack 200 is functionally broken down as follows: Figure 2B The radio protocol stack 250 is shown in the diagram. The CU at either base station 104 or 106 can retain all control and upper-layer functionality (e.g., RRC 214, SDAP 212, NR PDCP 210), while lower-layer operations (e.g., NR RLC 206B, NR MAC 204B, and NR PHY 202B) are delegated to the DU. To support connectivity to the 5GC, NR PDCP 210 provides SRBs to RRC 214, and NR PDCP 210 provides DRBs to SDAP 212 and SRBs to RRC 214.

[0060] Figure 3A An NTN deployment 300A, known as a transparent payload architecture, is illustrated. This NTN deployment involves a satellite gateway 302 and a “transparent” satellite 304 for extending the range of the Uu interface. Satellite 304 implements frequency conversion and radio frequency (RF) amplifiers in both the uplink and downlink directions. The satellite functions similarly to an analog RF repeater. Therefore, satellite 304 relays the Uu radio interface from the feeder link (between the NTN gateway and the satellite) to the serving link (between the satellite and the UE) in the downlink direction, and vice versa in the uplink direction. The satellite radio interface (SRI) on the feeder link is Uu, and NTN gateway 302 supports all the necessary functions for forwarding signals from the Uu interface. NTN gateway 302 can be placed at the same site as base station 104 (e.g., eNB, gNB) 104, or connected to base station 104 at a distance via a wired link. More than one NTN gateway can also be connected to the base station. Different transparent satellites can be connected to the same base station on the ground via the same NTN gateway or via different NTN gateways. Figure 3B The diagram shows a scenario 300B in which two different satellites (304 and 306) are connected to the same base station 104 via the same NTN gateway 302 and the two satellites (304 and 306) are using two different Physical Cell IDs (PCIs) to cover the Earth's surface.

[0061] Figure 4A The diagram illustrates the NTN user plane protocol stack 400A involving UE 102, satellite 304, NTN gateway 302, NR base station (i.e., gNB) 104, and UPF 114. The NTN user plane protocol stack diagram is similar to that of a terrestrial network (TN), with the addition of two new nodes—satellite 304 and NTN gateway 302—placed in the middle of the NR-Uu interface. Similarly, Figure 4B The NTN control plane protocol stack 400B shown is also similar to the protocol stack of a terrestrial network.

[0062] Regarding satellite mobility modes, there are at least three types of service links supported in NTN: (i) Earth-fixed: provided by a beam that continuously covers the same geographic area (e.g., in the case of GEO / GSO satellites); (ii) Quasi-Earth-fixed: provided by a beam that covers one geographic area for a limited time period and a different geographic area for another time period (e.g., in the case of LEO / MEO satellites that can use steerable beams); and (iii) Earth-moving: provided by a beam that slides above the Earth's surface (e.g., in the case of LEO / MEO satellites using fixed or non-steerable beams).

[0063] Using LEO / MEO satellites, eNBs can provide quasi-fixed cell coverage or mobile cell coverage. Using GEO satellites, eNBs can provide fixed cell coverage.

[0064] although Figure 3A / Figure 3B The transparent payload architecture shown is a current focus of 3GPP development, but a regenerative payload architecture that installs BS functions on the satellite is also a possible NTN deployment in the future. In such an architecture, Uu exists only between the satellite and the UE. Generally speaking, the technology disclosed herein can be applied to both transparent payload architectures and regenerative payload architectures.

[0065] Due to the long propagation delays in NTNs, HO (Hosting Operations) outages in NTNs are typically much longer than those in terrestrial networks (TNs). Furthermore, because certain satellites (e.g., LEO or MEO satellites) are constantly moving, and the cells projected by these satellites (on Earth) are also constantly moving, there can be a large number of UEs needing to switch to another cell at any given time. Therefore, HO “signaling storms,” or sudden spikes in traffic, are much more likely to occur in NTNs than in TNs. To reduce the impact of long HO outages and mitigate HO signaling storms in NTNs, 3GPP has proposed reducing the total number of handover attempts by allowing a deployment scenario known as “satellite handover with resynchronization.” In this deployment scenario, the incoming cell of an LEO or MEO satellite can use the same PCI as a cell previously serving the same geographic area, meaning that an LEO / MEO cell may need to change its PCI when moving from one geographic area to another.

[0066] Figure 5 This is an example of satellite handover scenario 500 with resynchronization, where a stationary UE switches from one satellite to another without performing a HO procedure because both satellites use the same PCI (or more generally, the same cell identifier) ​​to serve / project cells in the same geographic area (at different times). In this example, initially at time T1, UE 102 is served by a cell provided by satellite 304, and the synchronization signal block (SSB) transmitted from satellite 304 indicates the PCI (denoted as PCI) of the cell at time T1. T1 ) is k. Further assume that at time T1, UE 102 monitors the PDCCH transmitted from the antenna port that is quasi-co-located (QCL) with the antenna port of the transmission beam b1 (i.e., UE 102 receives service from the antenna port providing beam b1), where beam b1 may be the beam providing SSB or the beam providing channel state information reference signal (CSI-RS).

[0067] At a later time T2, satellite 304 is moving away from UE 102 and ceases service to the geographic area where the UE is located. Simultaneously, another satellite 306, managed by the same BS, moves in and begins using the same PCI (i.e., PCI...). T2 = k) to serve the same geographical area. Because the goal of satellite handover with a resynchronization process is to minimize service interruption time, UE 102 typically expects no coverage gap (or almost zero) in the vicinity of the time when the satellite handover occurs.

[0068] However, even if the satellite seamlessly provides the corresponding coverage without triggering a handover process, UE 102 may still fail to immediately monitor / decode the PDCCH after switching to the new beam b3 of the new satellite 306 without proper beam management / alignment. This is because UE 102 maintains the original PDCCH configuration and applies this configuration to incorrectly decode the PDCCH. More specifically, UE 102 may rely on assumptions about channel attributes that only apply if UE 102 has received service from satellite 304 via beam b1. Because if UE 102 cannot decode the PDCCH after satellite handover, the network cannot guarantee service continuity, it is expected that an updated PDCCH configuration and / or beam configuration, including the Transport Configuration Indicator (TCI) state configuration (based on the new beam settings for satellite 306), will be provided to UE 102 before the satellite handover occurs.

[0069] Next, refer to Figures 6 to 10 Several example scenarios are discussed in which the UE and / or RAN implement the techniques of this disclosure to configure the UE with beam and / or TCI states for PDCCH monitoring during satellite handover with a resynchronization process. Generally, Figures 6 to 10 Similar events in the figures are labeled with reference numerals that have the same lower digits. For example, event 604 is similar to event 704, event 610 is similar to events 710, 810, and 910, and event 620 is similar to events 720 and 820. For the sake of brevity, similar events are not discussed in detail in every case, but a discussion of an event with reference to one of the figures also applies to similar events in the other figures.

[0070] For simplicity, the term "idle state" will be used below to refer to the RRC_IDLE state and / or the RRC_INACTIVE state. The term "connected state" will refer to the RRC_CONNECTED state.

[0071] Figure 6 Figure 600 shows a message passing example scenario 600 in which UE 102, in a connected state, receives a TCI state activation indication shortly before a satellite handover with resynchronization occurs. Figure 6In this context, UE 102 initially connects to NTN cell 124 managed by BS 104 via satellite 304. While maintaining a connection at 602, UE 102 receives system information message 606 in NTN cell 124, which includes the t-Service value of the first cell (i.e., NTN cell 124), where t-Service indicates the time when the first cell will cease serving an area. UE 102 can also receive, via system information, t-ServiceStart value 604 in NTN cell 124, representing the time when the second cell (i.e., NTN cell 125) will begin serving an area. UE 102 can receive t-Service values ​​604 and 606, and the t-ServiceStart value, in a single message.

[0072] In one implementation, the time instance indicated by t-ServiceStart is always earlier than the time instance indicated by t-Service, corresponding to deployment scenarios where incoming and outgoing cells with the same PCI overlap in cell coverage. In another implementation, the time instance indicated by t-ServiceStart is later than the time instance indicated by t-Service, corresponding to deployment scenarios where there is a coverage gap between incoming and outgoing cells with the same PCI. In one implementation, BS 104 uses a specific information element (IE) in the system information to prepare for satellite handover with resynchronization (satellite handover without handover if the PCI does not change). In this case, if UE 102 only receives the t-Service value and not the t-ServiceStart value from BS 104, UE 102 assumes that the time instance at which the second cell (i.e., cell 125) will begin serving the area is the same as the time instance at which the first cell (i.e., cell 124) will cease serving the area (i.e., t-ServiceStart is equivalent to t-Service).

[0073] UE 102 may also optionally receive a 610 ssb-positionsInBurst IE via system information, a dedicated RRC message, or a DL MAC CE. This ssb-positionsInBurst IE indicates / includes the time-domain position of an SSB transmitted by satellite 306 in an SS burst, as defined, for example, in 3GPP TS 38.213 Clause 4.1. The ssb-positionsInBurst IE indicating the time-domain position of an SSB transmitted by satellite 306 may be the same as or different from the ssb-positionsInBurst IE indicating the time-domain position of an SSB transmitted by satellite 304.

[0074] Similarly, UE 102 may optionally receive a 620 csi-MeasConfig IE via a dedicated RRC message, which includes a configuration (i.e., an nzp-CSI-RS-Resource IE) for at least one non-zero power CSI-RS resource used by cell 125. The configuration for the at least one non-zero power CSI-RS resource may contain information elements shown below, as defined in Clause 6.3.2 of 3GPP TS 38.331:

[0075]

[0076]

[0077]

[0078] At a later time, but before the service area of ​​cell 124 ceases operation (i.e., before t-Service), UE 102 receives a 630 PDSCH configuration (e.g., pdsch-Config IE) that includes at least one TCI state configuration (e.g., TCI state) relating to an SSB or non-zero power CSI-RS resource transmitted / used by cell 125. The TCI state configuration may contain information elements shown below, as defined in 3GPP TS 38.331, Clause 6.3.2. For at least one TCI state configuration provided in event 630, csi-rs IE refers to a non-zero power CSI-RS resource configured for use by cell 125, or ssb IE refers to an SSB transmitted by cell 125.

[0079]

[0080]

[0081]

[0082] After receiving the 630 TCI state configuration, UE 102 receives the 640 PDCCH configuration, which includes at least one TCI-State configured for cell 125. An example format of the PDCCH configuration that UE 102 can receive for 640 is shown below. In this example, the PDCCH configuration adds one TCI-State configured for cell 125 (i.e., TCI-StateId 2) and removes all other TCI-States configured for cell 124 (i.e., TCI-StateId 1). Therefore, upon receiving the PDCCH configuration, UE 102 can immediately activate TCI-StateId 2 and begin monitoring the PDCCH based on the TCI state configuration associated with TCI-StateId 2. This is because TCI-StateId 2 is the only available TCI-State after UE 102 receives the 640 PDCCH configuration.

[0083]

[0084] In one implementation, the PDCCH configuration is associated with a flag / value / indicator that delays the application of the PDCCH configuration until a satellite handover with resynchronization occurs. In another implementation, the ControlResourceSet IE is associated with a flag / value / indicator that delays the application / compliance of the ControlResourceSet configuration until a satellite handover with resynchronization occurs. Still in another implementation, the tci-StatesPDCCH-ToAddList IE or tci-StatesPDCCH-ToReleaseList IE is associated with a flag / value / indicator that delays the application of tci-StatesPDCCH-ToAddList or tci-StatesPDCCH-ToReleaseList until a satellite handover with resynchronization occurs. In one implementation, if the PDCCH configuration / ControlResourceSet IE / tci-StatesPDCCH-ToAddList IE is associated with a flag / value / indication, then UE 102 will delay the application / compliance of the PDCCH configuration / ControlResourceSet / tci-StatesPDCCH-ToAddList by X time units, where the value X can be provided by BS 104 or can be a constant value hardcoded within UE 102.

[0085] In another implementation, UE 102 receives a PDCCH configuration in the following example format at 640. In this example, the PDCCH configuration adds a TCI state configured for cell 125 (i.e., TCI-StateId 2) without removing other TCI states configured for cell 124 (i.e., TCI-StateId 1, assuming it was previously configured for cell 124). Therefore, upon receiving the PDCCH configuration, UE 102 has multiple available TCI states and must rely on receiving a MAC CE designated to convey an indication of the TCI state for a UE-specific PDCCH (see event 650 below). An example format for this downlink MAC CE is defined in 3GPP TS 38.321, clause 6.1.3.15.

[0086]

[0087] Immediately before or shortly before a satellite handover with resynchronization occurs (i.e., immediately before or shortly before t-Service), UE 102 receives 650 a TCI state indication for a UE-specific PDCCH MAC CE, indicating "TCI-StateId 2" as the TCI state to be activated. In response to the reception of the downlink MAC CE at 650, UE 102 uses the CSI-RS or SSB resources indicated by TCI-StateId 2 to monitor the PDCCH in cell 125 at 660. Before starting to monitor the PDCCH transmitted in cell 125 at 660, UE 102 may need to shift the downlink frame / subframe / slot timing based on the timing offset value provided by BS 104 and / or based on the propagation delay difference estimated / calculated by the UE.

[0088] In one implementation, UE 102 begins PDCCH monitoring at t-Service or t-ServiceStart, rather than immediately after receiving the TCI status indication for the UE-specific PDCCH MAC CE at 650. In another implementation, after receiving the TCI status indication for the UE-specific PDCCH MAC CE at 650, UE 102 delays the start of PDCCH monitoring by X time units, where the value X may be provided by BS 104 or may be a constant value hardcoded within UE 102.

[0089] In some implementations, to indicate to UE 102 that reception 650 does not need to coincide with the start 660 of PDCCH monitoring, BS 104 uses a downlink MAC CE dedicated to transmitting TCI states not immediately applied at the UE. This MAC CE may have a dedicated logical channel identifier (LCID) so that UE 102 can distinguish this MAC CE from the MAC CE used for immediately applying TCI states at the UE. In some implementations, the MAC CE dedicated to transmitting TCI states not immediately applied has the same format as the "regular" MAC CE used for transmitting TCI states immediately applied. In any case, UE 102 can determine the type of MAC CE that calls UE 102 to wait until t-Service or t-ServiceStart to apply the indicated TCI state.

[0090] exist Figure 6 In the example scenario, t-ServiceStart occurs later than t-Service. In other words, cell 124 first stops serving area 670 at t-Service, and then cell 125 starts serving area 680 at t-ServiceStart. Because UE 102 has started monitoring PDCCH based on the latest channel attribute assumption of TCI-StateId 2 at 660 (assuming 660 and 670 occur simultaneously), UE 102 can successfully decode the PDCCH transmitted in cell 125 after t-ServiceStart, and therefore UE 102 can successfully communicate at 690 in cell 125 after t-ServiceStart.

[0091] Next, Figure 7 Example scenario 700 is shown, in which UE 102 in a connected state receives a PDCCH configuration including a deactivated TCI identifier and immediately before or shortly before a satellite handover with resynchronization occurs. Scenario 700 is generally similar to scenario 600, while the differences are discussed below. Figure 7 In the process, while maintaining the connection state at 702, UE 102 receives system information message 706 in NTN cell 124, which includes a t-Service value, where t-Service indicates the time when the first cell will stop serving the area in which UE 102 is operating and when the second cell will start serving the area.

[0092] After UE 102 receives 730, which includes a PDSCH configuration (e.g., pdsch-Config IE) involving at least one TCI state related to SSB or non-zero power CSI-RS resources transmitted / used in cell 125, UE 102 further receives 742, which includes a PDCCH configuration including a reference to one of the TCI state identifiers (e.g., TCI-StateId) configured 730 for cell 125. Therefore, the PDCCH configuration identifies the TCI state that UE 102 will activate later (this TCI state is deactivated when UE 102 receives the PDCCH configuration 742). In the example implementation shown below, the PDCCH configuration includes an IE within the ControlResourceSet IE indicating which TCI state in the TCI state list UE 102 should activate for PDCCH monitoring in a new NTN cell. In this example implementation, the IE is named TCI-StateID-toBeActivated and includes an integer value of TCI-StateId identifying the TCI state to be activated. In another implementation, one of the TCI-StateId values ​​in the tci-StatesPDCCH-ToAddList structure is followed (or preceded) by a flag indicating that UE 102 should activate this specific TCI state, while the other TCI-StateId values ​​in the tci-StatesPDCCH-ToAddList structure are not associated with this flag.

[0093]

[0094] Subsequently, at time t-Service, cell 124 ceased service area 770, and cell 125 began service area 780. Figure 6In different scenarios, for example, UE 102 only receives the 706 t-Service value and does not receive the t-ServiceStart value of event 604. In this case, UE 102 activates the TCI state corresponding to the TCI-StateId specified in the PDCCH configuration at 762. UE 102 begins monitoring the PDCCH transmitted in cell 125 using the channel attribute assumptions of the CSI-RS or SSB corresponding to the activated TCI-StateId at 762. Before monitoring the PDCCH transmitted in cell 125 at 762, UE 102 may need to shift the downlink frame / subframe / slot timing based on the timing offset value provided by BS 104 and / or based on the propagation delay difference estimated or calculated by UE 102. In one implementation, when UE 102 activates the 762 TCI-StateId, UE 102 also deactivates all other TCI-StateIds configured in the PDCCH configuration.

[0095] Next, Figure 8 Example scenario 800 is shown, in which UE 102 operating in connected state receives a PDSCH configuration including a deactivated TCI state, and immediately before or shortly before a satellite handover with resynchronization occurs, activates one of the deactivated TCI states. Scenario 800 is generally similar to scenario 600, while the differences are discussed below.

[0096] Here, after receiving csi-measConfig IE 820 containing configuration for at least one non-zero power CSI-RS resource used by cell 125, UE 102 receives PDSCH configuration 832 including at least one TCI state relating to SSB or non-zero power CSI-RS resource in cell 125. The received PDSCH configuration 832 indicates which at least one TCI state UE 102 will activate later, which is generally similar to Figure 7 The technology is similar to event 742. Therefore, for example, the PDSCH configuration can include appropriate flags, indicators, or values.

[0097] An example implementation of this is shown below. Here, the TCI state to be activated (e.g., TCI-StateId 2) contains an enumeration type IE (e.g., toBeActivated{true}) within the TCI-State IE, while the TCI states that are not deactivated (e.g., TCI-StateId 1 and 5) do not contain an enumeration type IE within the TCI-State IE.

[0098]

[0099]

[0100] In another implementation, another IE within the pdsch-Config IE (e.g., the TCI-StateID-toBeActivated indicator, which contains an integer value pointing to the TCI-StateId) indicates the TCI state to be activated.

[0101] Then, UE 102 may receive 840 a PDCCH configuration including one or more of the TCI-StateIds that are configured 832 for the TCI state of cell 125 (i.e., that is, that is, that is being deactivated via event 832).

[0102] Subsequently, at time t-ServiceStart, cell 125 begins serving area 880. At time t-Service (which is later than t-ServiceStart in this example), cell 124 ceases serving area 870. At time t-Service, UE 102 activates the TCI state corresponding to the TCI-StateId referenced in the PDCCH configuration and associated with the flag received in the PDSCH configuration (toBeActivated in this example) of 832. UE 102 uses the channel attribute assumptions of the CSI-RS or SSB involved in the activated TCI-StateId to monitor the PDCCH transmitted in cell 125 by UE 102. Before monitoring the PDCCH in cell 125 by UE 102, UE 102 may need to shift downlink frame / subframe / slot timing based on the timing offset value provided by BS 104 and / or based on the propagation delay difference estimated or calculated by UE 102.

[0103] In one implementation, when UE 102 activates TCI state 862, UE 102 also deactivates all other TCI states configured as 840 in the PDCCH configuration. In another implementation, UE 102 activates the TCI state 862 associated with a flag or indicated by an indicator / value in the PDSCH configuration at t-ServiceStart instead of at t-Service.

[0104] Now for reference Figure 9 In example scenario 900, UE 102, operating in connected state 902, receives a CSI measurement configuration including deactivated CSI-RS resources, and immediately before or shortly before a satellite handover with resynchronization occurs. Scenario 900 is generally similar to scenario 700, with differences discussed below.

[0105] exist Figure 9 In the above reference, after receiving ssb-positionsInBurst IE indicating / including the time-domain position of the SSB transmitted by satellite 306, the UE receives csi-measConfig IE including at least one non-zero power CSI-RS resource used in cell 125, as indicated by 910. The csi-measConfig IE identifies at least one non-zero power CSI-RS resource that UE 102 will activate later and is used to monitor the PDCCH in the target NTN cell. This is generally similar to the reference above. Figure 7 and Figure 8 The implementation discussed includes a flag or other suitable indicator for specifying the associated non-zero power CSI-RS resource in the csi-measConfig IE. An example implementation of this is shown below. Here, the non-zero power CSI-RS resource to be activated (NZP-CSI-RS-ResourceId 2) is associated with an enumeration type IE (e.g., toBeActivated{true}) within the NZP-CSI-RS-Resource IE, while the non-zero power CSI-RS resource that BS 104 is not guiding UE 102 to activate (e.g., NZP-CSI-RS-ResourceId 3) is not associated with an enumeration type IE within the NZP-CSI-RS-Resource IE. More specifically, here, the entry in the list corresponding to NZP-CSI-RS-ResourceId 2 includes the toBeActivated flag, while the remaining entries in the list do not.

[0106]

[0107] In another implementation, the csi-MeasConfig IE includes another IE for specifying the non-zero power CSI-RS resource to be activated. For example, the csi-MeasConfig IE may include an NZP-CSI-RS-toBeActivated IE containing an integer value pointing to the NZP-CSI-RS-ResourceId to be activated.

[0108] Then, UE 102 receives 930 a PDSCH configuration including at least one TCI state relating to the non-zero power CSI-RS resources used in cell 125, and then receives 944 a PDCCH configuration including one of the TCI-StateIds corresponding to the TCI state relating to the NZP-CSI-RS resources used in cell 125.

[0109] At time t-Service, cell 124 ceases service area 970, and cell 125 begins service area 980. At this time, UE 102 activates the NZP-CSI-RS resource specified in csi-MeasConfig 962 as 922, as discussed above. UE 102 also selects the TCI-StateId (specified in PDCCH configuration 944) corresponding to the TCI state of the NZP-CSI-RS-Resource that UE 102 is activating. UE 102 begins monitoring the PDCCH transmitted in cell 125 using channel attribute assumptions of the CSI-RS involved in the activated TCI state / TCI-StateId at time 962. Similar to the example above, UE 102 may need to shift downlink frame / subframe / slot timing based on the timing offset value provided by BS 104 and / or based on the propagation delay difference estimated / calculated by UE 102. In one implementation, when UE 102 activates 962 TCI-StateId (and its corresponding TCI state), UE 102 also deactivates all other TCI-StateIds (and their corresponding TCI states) configured in PDCCH 944.

[0110] Figure 10 This is a message passing diagram for example scenario 1000, where a connected UE 102 receives an SSB index or SSB time offset value that facilitates monitoring the PDCCH after a satellite handover with resynchronization. Scenario 1000 is generally similar to scenario 700, with differences discussed below. Here, after receiving 1010, an ssb-positionsInBurst IE indicating / including the time-domain position of the SSB transmitted by satellite 306, the UE receives 1012, the SSB index or SSB time offset value, for application after t-Service.

[0111] At time t-Service, cell 124 ceases service area 1070, and cell 125 begins service area 1080. At this time, UE 102 synchronizes with the SSB transmitted in cell 125 1064 based on the timing difference implied by the previously provided SSB index 1012 or SSB time offset, and monitors the 1064 PDCCH using the channel attribute assumptions of the SSB. Before synchronizing with the SSB transmitted in cell 125 1064, UE 102 may need to shift downlink frame / subframe / slot timing based on the timing offset value provided by BS 104 and / or based on the propagation delay difference estimated or calculated by UE 102.

[0112] For clarity, please refer to the following. Figures 11 to 20Several example methods that can be implemented by UE 102 or base station 104 are discussed. In these illustrations, dashed lines are used to indicate that the corresponding block is optional in at least some of the implementations of this method. Generally speaking, Figures 11 to 20 Similar events are identified using reference numerals with the same low-order digits. For example, event 1110 is similar to event 1210, and event 1263 is similar to event 1363.

[0113] Figures 11 to 20 Each of the methods can be implemented as software instructions stored on a computer-readable medium and executable by one or more processors.

[0114] Figure 11 This is a flowchart of an example method 1100 for activating a TCI state for PDCCH monitoring upon receiving downlink control information, which can be implemented in a UE (e.g., UE 102 in this disclosure). Initially, at block 1102, the UE receives a first time instance from the BS via system information or via a dedicated RRC message, in which a first cell will cease serving an area. At block 1104, the UE may also receive a second time instance from the BS via system information or via a dedicated RRC message, in which a second cell with the same PCI as the first cell will begin serving an area, wherein the second time instance may be earlier or later than the first time instance. In some implementations, at block 1103, the UE receives both the first and second time instances within the same message.

[0115] At box 1110, the UE can receive the time-domain position (i.e., ssb-PositionsInBurst) of the SS block transmitted in the second cell from the BS via system information or via a dedicated RRC message. At box 1112, the UE can receive the SSB index or offset, which the UE can apply at t-Service.

[0116] At box 1120, the UE receives a CSI measurement configuration from the BS via a dedicated RRC message, which includes at least one non-zero power CSI-RS resource used by the second cell. At box 1130, the UE further receives a PDSCH configuration from the BS, which includes at least one TCI state relating to the SSB or non-zero power CSI-RS resource used by the second cell. At box 1140, the UE also receives a PDCCH configuration from the BS via a dedicated RRC message, which includes at least one TCI-StateId from the TCI-StateIds corresponding to the TCI states configured for the second cell at box 1130. The PDCCH configuration may further include flags / indications that instruct the UE to delay the application of the PDCCH configuration for a specific time period, such as until a first time instance or until a second time instance (if signaled earlier).

[0117] At box 1150, when the UE has configured more than one TCI-StateId via PDCCH configuration, the UE receives from the BS via the downlink MAC CE an indication of which TCI-StateId configured in the PDCCH configuration should be activated in the first time instance or the second time instance (if signaled earlier). The downlink MAC CE can further instruct the UE to delay the activation of the indicated TCI-StateId for a specific period of time, until the first time instance, or until the second time instance (if the second time instance is signaled earlier).

[0118] At box 1160, after receiving the PDCCH configuration or after receiving the downlink MAC CE for TCI-StateId activation, the UE activates the TCI-StateId indicated in boxes 1140 or 1150. In one implementation, instead of performing box 1150 immediately after receiving the PDCCH configuration or the downlink MAC CE for TCI-StateId activation, the UE delays the application of the PDCCH configuration for a specific period of time, or waits until a first time instance or until a second time instance (if signaled earlier). Subsequently, at box 1161, the UE uses channel attribute assumptions about the SSB or CSI-RS resources associated with the activated TCI-StateId to monitor the PDCCH transmitted in the second cell.

[0119] Figure 12 This is a flowchart of an example method 1200 that can be implemented by a UE in a connected state (e.g., UE 102 in this disclosure) for receiving a PDCCH configuration including a deactivated TCI status identifier and determining when to activate the deactivated TCI status identifier. Figure 12The flowchart in the middle is similar to Figure 11 The flowchart in the diagram is as follows, with the differences discussed below. After receiving the PDSCH configuration from the BS at block 1230, the UE receives the PDCCH configuration from the BS at block 1242, which includes one of the TCI-StateIds configured for the second cell, where the TCI-StateId will be activated later (i.e., is being deactivated at this moment) and is associated with a flag or indicated by an indication / value.

[0120] At box 1262, in either the first or second time instance (if signaled earlier), the UE activates a TCI-StateId associated with a flag or indicated by an indication / value for PDCCH monitoring. At this time, the UE can also deactivate all other TCI-StateIds besides the one currently being activated. Then, at box 1263, the UE uses the channel attribute assumptions of the SSB or CSI-RS resources associated with the TCI-StateId being activated in 1262 to monitor the PDCCH transmitted in the second cell.

[0121] Figure 13 This is a flowchart of an example method 1300 that can be implemented by a UE in a connected state (e.g., UE 102 in this disclosure) for receiving a PDSCH configuration including a deactivated TCI state and determining when to activate the deactivated TCI state. Figure 13 The flowchart in the middle is similar to Figure 11 The flowcharts are as follows, with differences discussed below. After receiving the CSI measurement configuration from the BS at box 1320, at box 1332, the UE receives the PDSCH configuration from the BS, which includes at least one TCI state relating to the SSB or non-zero power CSI-RS resources used by the second cell, wherein at least one state will be activated later (i.e., is being deactivated at this moment) and is associated with a flag or indicated by an indication / value. Then, at box 1340, the UE receives the PDCCH configuration, which includes one of the TCI-StateIds corresponding to the TCI-State associated with the flag or indicated by an indication / value.

[0122] At box 1362, at either the first or second time instance (if signaled earlier), the UE activates the TCI-StateId configured at box 1340 for PDCCH monitoring. The TCI state of this TCI-StateId is associated with a flag or indicated by an indicator / value. At this time, the UE can also deactivate all other TCI-StateIds besides the one currently being activated. At box 1363, the UE uses the channel attribute assumptions of the SSB or CSI-RS resources involved in the TCI-StateId being activated at box 1362 to monitor PDCCH transmitted in the second cell.

[0123] Figure 14 This is a flowchart of an example method 1400 that can be implemented by a UE in a connected state (e.g., UE 102 in this disclosure) for receiving a CSI measurement configuration including deactivated CSI RS resources and determining when to activate the deactivated CSI RS resources. Figure 14 The flowchart in the middle is similar to Figure 11 The flowchart in the diagram is as follows, with the differences discussed below. After receiving the time-domain location of the SS block transmitted in the second cell from the BS, at box 1422, the UE receives a CSI measurement configuration from the BS, which includes at least one non-zero power CSI-RS resource used by the second cell, wherein the at least one non-zero power CSI-RS resource is associated with a flag or indicated by an indication / value.

[0124] At block 1430, the UE receives PDSCH configuration from the BS, which includes at least one TCI state relating to non-zero power CSI-RS resources used by the second cell, wherein at least one TCI state will be activated later. Then, at block 1444, the UE receives PDCCH configuration, which includes one of the TCI-StateIds corresponding to the TCI state relating to non-zero power CSI-RS resources used by the second cell.

[0125] At box 1462, at either the first or second time instance (if signaled earlier), the UE activates the TCI-StateId configured at box 1444 for PDCCH monitoring, the TCI state of which relates to non-zero power CSI-RS resources used by the second cell. At this time, the UE can also deactivate all other TCI-StateIds besides the one currently being activated. At box 1463, the UE monitors the PDCCH transmitted in the second cell using channel attribute assumptions based on the CSI-RS resources involved in the TCI-StateId being activated at box 1462.

[0126] Figure 15 This is a flowchart of an example method 1500 for receiving an SSB index or SSB time offset applicable after a satellite handover with resynchronization, which can be implemented by a UE in a connected state (e.g., UE 102 in this disclosure). Figure 15 The flowchart in the middle is similar to Figure 11 The flowchart is as follows, with differences discussed below. After receiving the time-domain location of the SS block transmitted in the second cell from the BS, at box 1512, the UE receives from the BS the SSB index and / or SSB time offset value to be applied after the first time instance or the second time instance (if signaled earlier).

[0127] At box 1564, at either the first or second time instance (if signaled earlier), the UE synchronizes with the SSB based on the timing difference implied by the SSB index or SSB time offset provided at box 1512, and uses channel attribute assumptions of the SSB being synchronized to monitor the PDCCH in the second cell. Prior to synchronizing with the SSB transmitted in the second cell, the UE may need to shift downlink frame / subframe / slot timing based on the timing offset value provided by the BS and / or based on the propagation delay difference estimated / calculated by the UE.

[0128] Next, Figure 16An example method 1600 for activating a TCI state for PDCCH monitoring during satellite handover with a resynchronization process is illustrated and can be implemented by a BS (e.g., BS 104 in this disclosure). At block 1604, the BS transmits a first time instance to the UE via system information or via a dedicated RRC message, at which a first cell will cease serving. At block 1606, the BS may also transmit a second time instance to the UE via system information or via a dedicated RRC message, at which a second cell with the same PCI as the first cell will begin serving. In some implementations, the BS transmits the first and second time instances in a single message.

[0129] When the BS does not send a second time instance to the UE, but instead sends other information related to satellite handover with a resynchronization process, the UE can infer that the second cell, which has the same PCI (as the first cell), will begin serving at the same time that the first cell will cease serving. At block 1610, the BS can transmit to the UE the time-domain location of the SSB transmitted in the second cell.

[0130] At box 1640, the BS transmits a PDCCH configuration, including more than one TCI-StateId, to the UE via a dedicated RRC message, where each TCI-StateId corresponds to a TCI state configuration provided in the PDSCH configuration. At box 1645, the BS determines which reference signal (i.e., which SSB or CSI-RS resource) is quasi-co-located with the PDCCH DMRS transmission for the UE in the second cell. The determination at box 1645 may be based on CSI reports from the UE, the UE's GNSS information, and / or ephemeris information from outgoing and incoming satellites. Finally, at box 1650, the BS transmits an indication to the UE via a downlink MAC CE of which TCI-StateId configured in the PDCCH configuration should be activated after X time units or after the first time instance or the second time instance (if signaled earlier).

[0131] Figure 17A This is a flowchart of an example method 1700A for configuring a deactivated TCI status identifier in a PDCCH configuration, which can be implemented by a BS (e.g., BS 104 in this disclosure), wherein the deactivated TCI status identifier is to be activated during satellite handover with a resynchronization process. Figure 17A The flowchart in the middle is similar to Figure 16The flowchart is as follows, with differences discussed below. After transmitting the time-domain location of the SSB transmitted in the second cell to the UE (at box 1710), the BS determines at box 1745 which reference signal (i.e., which SSB or CSI-RS resource) is quasi-co-located with the PDCCH DMRS transmission for the UE in the second cell. Subsequently, at box 1742, the BS transmits to the UE an indication (via flags / indicators / values) of which TCI-StateId should be activated (i.e., currently being deactivated) after the first time instance or the second time instance (if signaled earlier), where the deactivated TCI-StateId refers to the reference signal (i.e., SSB or CSI-RS resource) determined at box 1745.

[0132] Figure 17B This is a flowchart of an example method 1700B for configuring a deactivated TCI state in a PDSCH configuration, which can be implemented by a BS (e.g., BS 104 in this disclosure), wherein the deactivated TCI state is to be activated during satellite handover with a resynchronization process. Figure 17B The flowchart in the middle is similar to Figure 17A The flowchart in the diagram is as follows, with the differences discussed below. After determining (at box 1745) which reference signal is quasi-co-located with the PDCCH DMRS transmission for the UE in the second cell, the BS transmits to the UE at box 1732 a PDSCH configuration indicating (via flags / indicators / values) which TCI state should be activated (i.e., currently being deactivated) after the first time instance or the second time instance (if signaled earlier), where the TCI state being deactivated refers to the reference signal determined at box 1745.

[0133] Figure 17C This is a flowchart of an example method 1700C for configuring deactivated CSI-RS resources in a CSI measurement configuration, which can be implemented by a BS (e.g., BS 104 in this disclosure), wherein the deactivated CSI-RS resources are to be activated during satellite handover with a resynchronization process. Figure 17C The flowchart in the middle is similar to Figure 16 The flowchart is as follows, with differences discussed below. After transmitting the time-domain location of the SSB in the second cell to the UE (at box 1710), the BS determines at box 1745 which CSI-RS resource is quasi-co-located with the PDCCH DMRS transmission for the UE in the second cell. Subsequently, at box 1722, the BS transmits to the UE an indication (via flags / indicators / values) of which non-zero power CSI resource should be activated (i.e., currently being deactivated) after the first time instance or the second time instance (if signaled earlier).

[0134] Figure 18 This is a flowchart of an example method 1800 for configuring an SSB index or SSB time offset applicable to the UE after a satellite handover with resynchronization, which can be implemented by a BS (e.g., BS 104 in this disclosure). Figure 18 The flowchart in the middle is similar to Figure 16 The flowchart is as follows, with differences discussed below. After transmitting the time-domain location of the SSB transmitted in the second (target) cell to the UE (at box 1810), the BS determines at box 1845 which SSB is quasi-co-located with the PDCCH DMRS transmission for the UE in the second (target) cell. Subsequently, at box 1812, the BS transmits to the UE the SSB index and / or SSB time offset value to be applied after the first time instance or the second time instance (if signaled earlier).

[0135] Figure 19 This is a flowchart of an example channel monitoring method 1900 that can be implemented in a UE such as UE 102.

[0136] At box 1902, the UE receives QCL configuration in the serving cell for monitoring channels in the target cell, where the serving cell and the target cell have the same PCI (e.g., see events 630, 730, 832, 930, 1012; also see boxes 1112, 1120, 1130, 1140, 1212, 1220, 1230, 1242, 1312, 1320, 1332, 1430, 1412, 1422, 1430, 1444, 1510). QCL configuration in various embodiments and / or scenarios may include the ability to configure multiple TCI states, including an indication of the SSB location of the target cell, including configuration for at least one non-zero power CSI-RS resource of the target cell, including PDSCH configuration or PDCCH configuration, wherein the PDSCH configuration includes configuration for multiple TCI states or configuration for at least one non-zero power CSI-RS resource of the target cell, and the PDCCH configuration includes at least one TCI state identifier.

[0137] At box 1905, the UE receives an indication in the serving cell of the time relating to a change in coverage for the serving cell and / or the target cell in the area where the UE is located (e.g., see events 604, 606, 650, 706, 804, 906, 1006; also see boxes 1102, 1104, 1112, 1202, 1206, 1212, 1304, 1306, 1312, 1404, 1406, 1412, 1504, 1506).

[0138] At box 1965, the UE begins monitoring the channels in the target cell according to the QCL configuration and at the indicated time (see, for example, events 660, 762, 862, 962, 1064; also see boxes 1161, 1263, 1363, 1463, 1564).

[0139] Figure 20 This is a flowchart of an example configuration method 2000 that can be implemented in a RAN node such as base station 104.

[0140] At box 2001, the RAN node transmits to the UE in the serving cell a time indication related to a change in coverage for the serving cell and / or the target cell in the area where the UE is located (e.g., see events 604, 606, 650, 706, 804, 906, 1006; also see boxes 1102, 1104, 1112, 1202, 1206, 1212, 1304, 1306, 1312, 1404, 1406, 1412, 1504, 1506).

[0141] At box 2007, the RAN node transmits the QCL configuration for monitoring channels in the target cell to the UE in the serving cell, where the QCL configuration is based on the determination of which reference signal is quasi-co-located with the transmission on the channel (e.g., see events 630, 730, 832, 930, 1012; also see boxes 1645, 1745, 1845).

[0142] The following list of examples reflects various embodiments explicitly contemplated in this disclosure.

[0143] Example 1. A channel monitoring method implemented in a user equipment (UE), the method comprising: receiving in a serving cell a quasi-co-location (QCL) configuration for monitoring a channel in a target cell having the same cell identifier as the serving cell; receiving in the serving cell an indication of a time relating to a change in coverage of at least one of the serving cell or the target cell; and initiating the monitoring of the channel in the target cell according to the QCL configuration and at the indicated time.

[0144] Example 2. The method as described in Example 1, wherein: the QCL configuration configures a plurality of Transmission Configuration Indication (TCI) states; the method further includes: after receiving the QCL configuration, receiving an indication of a TCI state among the plurality of TCI states in the serving cell for the monitoring of the channel.

[0145] Example 3. The method as described in Example 2, wherein: the reception of the indication of the time includes the reception of the indication of the TCI state; and the start of the monitoring of the channel in the target cell occurs immediately after the reception of the indication of the TCI state.

[0146] Example 4. The method as described in Example 2, wherein: the reception of the indicated time includes the reception of the indicated TCI state; and the start of the monitoring of the channel in the target cell occurs after a predetermined amount of time following the reception of the indicated TCI state.

[0147] Example 5. The method as described in Example 4, wherein: the reception of the indicated time further includes a reception offset value, wherein the predetermined amount of time following the reception of the indicated TCI state is based on the received offset value.

[0148] Example 6. The method as described in Example 2 further includes: after the receipt of the indication of the TCI state, delaying the start of the monitoring until the indicated time.

[0149] Example 7. The method as described in Example 6, wherein the indication of the time includes: a first time for the end of coverage in the serving cell of the UE, and a second time for the start of coverage in the target cell of the UE; wherein the monitored start occurs at a later time than the first time and the second time.

[0150] Example 8. The method of any one of Examples 4 to 7, wherein: the indication of the TCI state is included in a Media Access Control (MAC) control element (CE) dedicated to transmitting the type of the TCI state for non-immediate application at the UE.

[0151] Example 9. The method of any one of Examples 2 to 8, wherein the QCL configuration includes one or more of the following: (i) an indication of the location of the Synchronization Signal Block (SSB) of the target cell, (ii) a configuration for at least one non-zero power Channel State Information Reference Signal (CSI-RS) resource of the target cell, (iii) a Physical Downlink Shared Channel (PDSCH) configuration including the configuration for the plurality of TCI states or the configuration for the at least one non-zero power CSI-RS resource of the target cell, or (iv) a Physical Downlink Control Channel (PDCCH) configuration including at least one TCI state identifier.

[0152] Example 10. The method of Example 1 further includes: receiving an indication of the monitored TCI status for the channel in a message including the QCL configuration.

[0153] Example 11. The method as described in Example 10, wherein: the QCL configuration includes a PDCCH configuration, the PDCCH configuration including (i) a plurality of TCI status identifiers, and (ii) an indication of which of the plurality of TCI status identifiers corresponds to the TCI status of the monitoring for the channel.

[0154] Example 12. The method as described in Example 11, wherein the QCL configuration further includes one or more of the following: (i) an indication of the SSB location of the target cell, (ii) a configuration for at least one non-zero power CSI-RS resource of the target cell, or (iii) a PDSCH configuration including a configuration for the plurality of TCI states or the configuration for the at least one non-zero power CSI-RS resource of the target cell.

[0155] Example 13. The method as described in Example 10, wherein: the QCL configuration includes a Physical Downlink Shared Channel (PDSCH) configuration, the PDSCH configuration including (i) a plurality of TCI state configurations, and (ii) an indication of which of the plurality of TCI state configurations is applied to the TCI state for the monitoring of the channel.

[0156] Example 14. The method as described in Example 13, wherein the QCL configuration further includes one or more of the following: (i) an indication of the SSB location of the target cell, (ii) a configuration for at least one non-zero power CSI-RS resource of the target cell, or (iii) a PDCCH configuration including at least one TCI status identifier.

[0157] Example 15. The method as described in Example 10, wherein: the QCL configuration includes a CSI measurement configuration, the CSI measurement configuration including (i) a plurality of CSI reference signal (CSI-RS) configurations, and (ii) an indication of which of the plurality of CSI-RS configurations the UE will use for the monitoring of the channel, wherein the TCI state is associated with the indicated CSI-RS configuration among the plurality of CSI-RS configurations.

[0158] Example 16. The method as described in Example 15, wherein the QCL configuration further includes one or more of the following: (i) an indication of the SSB location of the target cell, (ii) a PDSCH configuration including the configuration for the plurality of TCI states or the configuration for the at least one non-zero power CSI-RS resource of the target cell, or (iii) a physical downlink control channel (PDCCH) configuration including at least one TCI state identifier.

[0159] Example 17. The method as described in any one of Examples 10 to 16, wherein: the indication of the time indicates when coverage in the serving cell for the UE ends.

[0160] Example 18. The method as described in any of the preceding examples, wherein: the indication of the time further indicates when coverage in the target cell for the UE begins; wherein the monitored start occurs at a later time than the first time and the second time.

[0161] Example 19. The method as described in Example 1, wherein: the QCL configuration indicates the SSB parameters used for the monitoring of the channel at the indicated time.

[0162] Example 20. The method of Example 18, further comprising: using the SSB parameters to synchronize with an SSB transmitted in the target cell; wherein the monitoring of the channel in the target cell is based on the SSB.

[0163] Example 21. The method as described in any of the preceding examples further includes: suppressing the handover process when switching from the serving cell to the target cell.

[0164] Example 22. A configuration method implemented in a radio access network (RAN) node, the method comprising: transmitting to a serving cell of a user equipment (UE) an indication of time relating to a change in coverage of at least one of (a) the serving cell or (b) a target cell having the same cell identifier as the serving cell; and transmitting to the UE in the serving cell a quasi-co-address (QCL) configuration for monitoring a channel in the target cell, the QCL configuration being based on a determination of which reference signal of the UE in the target cell is quasi-co-addressed with a transmission on the channel.

[0165] Example 23. The method as described in Example 22, wherein the reference signal is a synchronization signal block (SSB) signal.

[0166] Example 24. The method as described in Example 22, wherein the reference signal is a channel state information reference signal (CSI-RS).

[0167] Example 25. The method of any one of Examples 22 to 24, further comprising: performing the determination using a CSI report from the UE.

[0168] Example 26. The method of any one of Examples 22 to 25, further comprising: using Global Navigation Satellite System (GNSS) information from the UE to make the determination.

[0169] Example 27. The method of any one of Examples 22 to 26 further includes: performing the determination using first ephemeris information of the serving cell and its associated first satellite and / or second ephemeris information of the target cell and its associated second satellite.

[0170] Example 28. The method of any one of Examples 22 to 27, wherein the indication of the time includes: a first time for the end of coverage in the serving cell of the UE, or a second time for the start of coverage in the target cell of the UE.

[0171] Example 29. A method as described in any one of Examples 22 to 28, wherein: the QCL configuration configures a plurality of Transmission Configuration Indication (TCI) states; the method further comprises: transmitting an indication of a TCI state among the plurality of TCI states in the serving cell after transmitting the QCL configuration for the monitoring of the channel.

[0172] Example 30. The method as described in Example 29, wherein: the indication of the TCI state is included in a Media Access Control (MAC) control element (CE) dedicated to transmitting the type of the TCI state for non-immediate application at the UE.

[0173] Example 31. The method as described in Example 29 or 30, wherein the QCL configuration includes one or more of the following: (i) an indication of the location of the Synchronization Signal Block (SSB) of the target cell, (ii) a configuration for at least one non-zero power Channel State Information Reference Signal (CSI-RS) resource of the target cell, (iii) a Physical Downlink Shared Channel (PDSCH) configuration including the configuration for the plurality of TCI states or the configuration for the at least one non-zero power CSI-RS resource of the target cell, or (iv) a Physical Downlink Control Channel (PDCCH) configuration including at least one TCI state identifier.

[0174] Example 32. The method of any one of Examples 22 to 31, further comprising: transmitting an indication of the monitored TCI state for the channel in a message including the QCL configuration.

[0175] Example 33. The method as described in Example 32, wherein: the QCL configuration includes a PDCCH configuration, the PDCCH configuration including (i) a plurality of TCI status identifiers, and (ii) an indication of which of the plurality of TCI status identifiers corresponds to the TCI status of the monitoring for the channel.

[0176] Example 34. The method as described in Example 33, wherein the QCL configuration further includes one or more of the following: (i) an indication of the SSB location of the target cell, (ii) a configuration for at least one non-zero power CSI-RS resource of the target cell, or (iii) a PDSCH configuration including a configuration for the plurality of TCI states or the configuration for the at least one non-zero power CSI-RS resource of the target cell.

[0177] Example 35. The method as described in Example 34, wherein: the QCL configuration includes a Physical Downlink Shared Channel (PDSCH) configuration, the PDSCH configuration including (i) a plurality of TCI state configurations, and (ii) an indication of which of the plurality of TCI state configurations is applied to the TCI state for the monitoring of the channel.

[0178] Example 36. The method as described in Example 35, wherein the QCL configuration further includes one or more of the following: (i) an indication of the SSB location of the target cell, (ii) a configuration for at least one non-zero power CSI-RS resource of the target cell, or (iii) a PDCCH configuration including at least one TCI status identifier.

[0179] Example 37. The method as described in Example 36, wherein: the QCL configuration includes a CSI measurement configuration, the CSI measurement configuration including (i) a plurality of CSI reference signal (CSI-RS) configurations, and (ii) an indication of which of the plurality of CSI-RS configurations the UE will use for the monitoring of the channel, wherein the TCI state is associated with the indicated CSI-RS configuration among the plurality of CSI-RS configurations.

[0180] Example 38. The method as described in Example 37, wherein the QCL configuration further includes one or more of the following: (i) an indication of the SSB location of the target cell, (ii) a PDSCH configuration including the configuration for the plurality of TCI states or the configuration for the at least one non-zero power CSI-RS resource of the target cell, or (iii) a physical downlink control channel (PDCCH) configuration including at least one TCI state identifier.

[0181] Example 39. The method as described in any of the preceding examples, wherein the channel in the target cell is a PDCCH.

[0182] Example 40. The method as described in any of the preceding examples, wherein the cell identifier is a Physical Cell Identifier (PCI).

[0183] Example 41. The method as described in any of the preceding examples, wherein the first cell and the second cell are associated with a non-terrestrial network (NTN).

[0184] Example 42. An apparatus including a transceiver and configured to implement the method according to any of the preceding examples.

[0185] The following descriptions can be applied to the descriptions above.

[0186] Generally, a description of one of the above figures can be applied to another of the above figures. If there is no conflict, the examples, implementations, and methods described above can be combined. The events or boxes described above may be optional or omitted. For example, events or boxes with dashed lines in the attached figures may be optional. In some implementations, "message" is used and "information element (IE)" can be used instead of "message," and vice versa. In some implementations, "IE" is used and "field" can be used instead of "IE," and vice versa. In some implementations, "configurations" or "configuration parameters" can be used instead of "configuration," and vice versa. In some implementations, "some" means "one or more." In some implementations, "at least one" means "one or more."

[0187] User devices (e.g., UE 102) that can implement the technologies disclosed herein can be any suitable device capable of wireless communication, such as smartphones, tablet computers, laptop computers, mobile game consoles, point-of-sale (POS) terminals, health monitoring devices, drones, cameras, media streaming dongles or other personal media devices, wearable devices (such as smartwatches), wireless hotspots, femtocells, or broadband routers. Additionally, in some cases, the user device can be embedded in electronic systems (such as the main unit of a vehicle or an advanced driver assistance system (ADAS)). Furthermore, the user device can operate as an Internet of Things (IoT) device or a mobile internet device (MID). Depending on the type, the user device may include one or more general-purpose processors, computer-readable storage, a user interface, one or more network interfaces, one or more sensors, etc.

[0188] Some embodiments described in this disclosure include logic or multiple components or modules. A module can be a software module (e.g., code or machine-readable instructions stored on a non-transitory machine-readable medium) or a hardware module. A hardware module is a tangible unit capable of performing certain operations and can be configured or arranged in a certain way. A hardware module may include a dedicated circuit system or logic (e.g., as a dedicated processor, such as a field-programmable gate array (FPGA) or application-specific integrated circuit (ASIC), digital signal processor (DSP), etc.) permanently configured to perform certain operations. A hardware module may also include programmable logic or circuit systems temporarily configured by software to perform certain operations (e.g., as included within a general-purpose processor or other programmable processor). The decision to implement a hardware module in a dedicated and permanently configured circuit system or in a temporarily configured circuit system (e.g., configured by software) may be driven by cost and time considerations.

[0189] As used herein, the term “or” should be interpreted as inclusive, or means any one or any combination thereof, unless otherwise expressly indicated, mutually exclusive, or indicated by the context. Thus, in this document, expressing “A or B” means “A, B, or both A and B”.

[0190] When implemented in software, these technologies can be provided as part of an operating system, a library used by multiple applications, or a specific software application. The software can be executed by one or more general-purpose processors or one or more dedicated processors.

[0191] Upon reading this disclosure, those skilled in the art will understand additional and alternative structural and functional designs for handling mobility between base stations using the principles disclosed herein. Therefore, while specific embodiments and applications have been shown and described, it should be understood that the disclosed embodiments are not limited to the precise constructions and components disclosed herein. Various modifications, alterations, and variations that will be apparent to those skilled in the art may be made to the arrangement, operation, and details of the methods and apparatus disclosed herein without departing from the spirit and scope defined in the appended claims.

Claims

1. A channel monitoring method implemented in a user equipment (UE), the method comprising: Receive quasi-co-location QCL configuration in the serving cell for monitoring channels in a target cell that has the same cell identifier as the serving cell; Receive in the serving cell an indication of the time related to a change in coverage of at least one of the serving cell or the target cell; as well as Monitoring of the channel in the target cell begins according to the QCL configuration and at the indicated time.

2. The method of claim 1, wherein: The QCL configuration configures multiple transport configuration indicators (TCI) statuses. The method further includes: After receiving the QCL configuration, the indices of the TCI states among the plurality of TCI states are received in the serving cell for the monitoring of the channel.

3. The method of claim 2, wherein: The receipt of the indication of the time includes the receipt of the indication of the TCI state; and The start of monitoring of the channel in the target cell occurs immediately after the reception of the indication in the TCI state.

4. The method of claim 2, wherein: The receipt of the indication of the time includes the receipt of the indication of the TCI state; and The start of monitoring of the channel in the target cell occurs after a predetermined amount of time following the reception indicated by the TCI state.

5. The method of claim 4, wherein: The receipt of the indicated time further includes a receipt offset value. Wherein, the predetermined time amount following the reception indicated in the TCI state is based on the received offset value.

6. The method of claim 2, further comprising: After the receipt of the indication of the TCI status, the start of the monitoring is delayed until the indicated time.

7. The method of claim 6, wherein, The indication of the time includes: For the first time when coverage ends in the serving cell of the UE, and The second time at which coverage begins in the target cell for the UE; The monitoring begins at a later time than the first time and the second time.

8. The method according to any one of claims 4 to 7, wherein: The indication of the TCI state is included in a Media Access Control (MAC) control element (CE) dedicated to transmitting the type of TCI state for non-immediate application at the UE.

9. A configuration method implemented in a radio access network (RAN) node, the method comprising: In the serving cell of the user equipment (UE), an indication of time relating to a change in coverage of at least one of (a) the serving cell or (b) a target cell having the same cell identifier as the serving cell is transmitted to the UE. as well as In the serving cell, a quasi-co-address QCL configuration for monitoring channels in the target cell is transmitted to the UE. The QCL configuration is based on determining which reference signal of the UE in the target cell is quasi-co-addressed with the transmission on the channel.

10. The method of claim 9, wherein, The indication of the time includes: At the first moment when coverage in the serving cell of the UE ends, or The second time when coverage begins in the target cell for the UE.

11. The method of claim 9 or 10, wherein: The QCL configuration configures multiple transport configuration indicators (TCI) statuses. The method further includes: After transmitting the QCL configuration, an indication of the TCI state among the plurality of TCI states is transmitted in the serving cell for the monitoring of the channel.

12. The method of claim 11, wherein: The indication of the TCI state is included in a Media Access Control (MAC) control element (CE) dedicated to transmitting the type of TCI state for non-immediate application at the UE.

13. The method of any one of claims 9 to 12, further comprising: The message including the QCL configuration transmits an indication of the TCI status for the monitoring of the channel.

14. The method of claim 12, wherein: The QCL configuration includes a PDCCH configuration, which includes (i) a plurality of TCI status identifiers and (ii) an indication of which of the plurality of TCI status identifiers corresponds to the TCI status of the monitoring used for the channel.

15. An apparatus comprising a transceiver and configured to implement the method according to any one of the preceding claims.

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