Managing measurement gap configurations for positioning measurements

Abstract

To configure reference signal measurements at a user equipment (UE), a central unit (CU) of a distributed base station further comprising a distributed unit (DU) sends (504) to the DU a first message comprising a request for configuring a measurement gap for the UE; receiving (507), from the DU, a second message comprising a measurement gap configuration; and providing (512) the measurement gap configuration to the UE for use with the reference signal measurement.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority and filing date of Provisional U.S. Patent Application No. 63 / 339,966, entitled “Managing Measurement Gap Configuration for Positioning Measurement,” filed on May 9, 2022. The entire contents of the provisional application are hereby expressly incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to wireless communications, and more particularly to managing measurement gap configurations for positioning measurements. Background Art

[0004] This background description is provided for the purpose of generally presenting the context of the present disclosure. The work of the presently named inventors is neither explicitly nor implicitly admitted to be prior art to the present disclosure to the extent that it is described in this background section and in all aspects that may not have otherwise qualified as prior art at the time of filing.

[0005] Location services (LCS) allow a user equipment unit (UE) and / or a base station to determine the geographic location of a UE when, for example, the UE is unable to determine its location due to limited hardware capabilities, the UE receives insufficient satellite or other beacon signals, or the base station attempts to locate the UE in an emergency situation.

[0006] For example, entities supporting LCS in the core network (CN) include a location management function (LMF) and an evolved service mobile location center (E-SMLC). In some examples, the UE exchanges messages with the LMF using a positioning protocol such as the LTE Positioning Protocol (LPP). Similarly, the UE sends the LPP message to an access management function (AMF) operating in the CN in an uplink (UL) non-access stratum (NAS) transport message. The AMF then sends the LPP message to the LMF or E-SMLC. In the downlink direction, the AMF sends the LPP message from the LMF or E-SMLC to the UE using a downlink (DL) NAS transport message.

[0007] A preconfigured measurement gap procedure is specified for positioning measurement. More specifically, the LMF sends a Measurement Preconfiguration Required message to the gNB to request the gNB to configure a preconfigured measurement gap for the UE. After receiving the Measurement Preconfiguration Required message or in response to receiving the Measurement Preconfiguration Required message, the gNB sends an RRC Reconfiguration message including the preconfigured measurement gap configuration to the UE. Later, when the gNB receives a Measurement Activation message from the LMF or receives an UL MAC control element requesting activation of the measurement configuration, the gNB sends a Positioning Measurement Gap Activation Command to the UE to activate the preconfigured measurement gap configuration. In response to receiving the Positioning Measurement Gap Activation Command or after receiving the Positioning Measurement Gap Activation Command, the UE activates the preconfigured measurement gap configuration and performs measurements on DL reference signals (e.g., Positioning Reference Signals (PRS)) for positioning using the preconfigured measurement configuration. However, it is unclear how to configure and activate the preconfigured measurement gap in a distributed base station. Furthermore, it is unclear how to deactivate and / or release the preconfigured measurement gap configuration in the distributed base station. Summary of the invention

[0008] An example embodiment of the technology of the present disclosure is a method for configuring reference signal measurement at a UE. The method is implemented in a central unit (CU) of a distributed base station that also includes a distributed unit (DU), and includes: sending a first message including a request to configure a measurement gap of the UE to the DU; receiving a second message including a measurement gap configuration from the DU; and providing the measurement gap configuration to the UE for use with the reference signal measurement.

[0009] Another example embodiment of these techniques is a method for configuring reference signal measurements at a UE, the method being implemented in a DU of a distributed base station that also includes a CU. The method includes receiving a first message from the CU, the first message including a request to configure a measurement gap of the UE; and sending a second message to the CU, the second message including a measurement gap configuration.

[0010] Another example embodiment of the techniques is a radio access network (RAN) node comprising processing hardware and configured to implement one of the methods described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1A is a block diagram of an example wireless communication system in which user devices and base stations of the present disclosure may implement the techniques of the present disclosure for managing small data transmissions;

[0012] Figure 1B The centralized unit (CU) and the distributed unit (DU) can be Figure 1A A block diagram of an example base station operating in a system of FIG.

[0013] Figure 2A yes Figure 1A A block diagram of an example protocol stack according to which a UE communicates with a base station;

[0014] Figure 2B yes Figure 1A A block diagram of an example protocol stack according to which a UE communicates with a CU and a DU; and

[0015] Figure 3A An example scenario is illustrated in which a DU and a CU send a gap configuration and information for activating and performing gap measurements;

[0016] Figure 3B Illustrated with Figure 3A Similar example scenario, but where the CU requests the gap configuration from the DU in a request message;

[0017] Figure 3C Illustrated with Figure 3A Similar example scenario, but where the DU sends the gap configuration in the measurement preconfiguration confirm response;

[0018] Figure 3D Illustrated with Figure 3A Similar example scenario, but where the UE deactivates the gap configuration after activating the configuration and / or performing measurements using such;

[0019] Figure 3E Illustrated with Figure 3A Similar example scenario, but where the CU and DU send messages to release the gap configuration at the UE;

[0020] Figure 3F Illustrated with Figure 3E Similar example scenario, but where the DU determines to release the gap configuration at the UE;

[0021] Figure 4A is a flow chart of an example method implemented in a DU for sending a gap configuration to a CU and then sending a measurement gap activation command to a UE after receiving a response from the CU;

[0022] Figure 4B is with Figure 4A A flow chart of a similar example method, but wherein the DU receives a request for gap configuration from the CU;

[0023] Figure 4C is with Figure 4AFlowchart of a similar example method, but where the DU sends a gap configuration to the CU and then sends an activation command to the UE;

[0024] Figure 5A is a flow chart of an example method implemented in a CU for receiving a gap configuration from a DU and sending a response including the gap configuration to the CU;

[0025] Figure 5B is with Figure 5A A flow chart of a similar example method, but wherein the CU sends a request for a gap configuration to the DU and receives the configuration from the DU;

[0026] Figure 5C is with Figure 5A A flow chart of a similar example method, but wherein the CU receives a gap configuration from the DU in response to a request for configuring a measurement gap for the UE;

[0027] Figure 6 is a flow chart of an example method implemented in a CU for determining whether to send a first set or a second set of measurement gap information based on whether the measurement gap is used for positioning measurement.

[0028] Fig. 7A is a flow chart of an example method implemented in a CU for receiving a message including gap release information from a DU and sending the message including gap release information to a UE via the DU;

[0029] Figure 7B is with Fig. 7A A flow chart of a similar example method, but wherein the CU generates release information for releasing the gap configuration at the UE; and

[0030] Figure 8 is a flow chart of an example method implemented in a DU for receiving a message for releasing a gap configuration of a UE from a CU and sending release information to the UE.

[0031] Specific implementation method

[0032] First reference Figure 1A , the example wireless communication system 100 includes a UE 102, a base station (BS) 104, a base station 106, and a core network (CN) 110. The base stations 104 and 106 may operate in a RAN 105 connected to the core network (CN) 110. For example, the CN 110 may be implemented as an evolved packet core (EPC) 111 or a fifth generation (5G) core (5GC) 160. In another example, the CN 110 may also be implemented as a sixth generation (6G) core.

[0033] Base station 104 covers cell 124, and base station 106 covers cell 126. If base station 104 is a gNB, cell 124 is an NR cell. If base station 104 is an ng-eNB, cell 124 is an Evolved Universal Terrestrial Radio Access (E-UTRA) cell. Similarly, if base station 106 is a gNB, cell 126 is an NR cell, and if base station 106 is an ng-eNB, cell 126 is an E-UTRA cell. Cells 124 and 126 may be located in the same radio access network notification area (RNA) or in different RNAs. In general, RAN 105 may include any number of base stations, and each of the base stations 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, 106 may be connected to CN 110 via an interface (e.g., S1 or NG interface). The base stations 104 and 106 may also be interconnected via an interface for interconnecting NG RAN nodes (e.g., an X2 or Xn interface).

[0034] Among other components, the EPC 111 may include a serving gateway (SGW) 112, a mobility management entity (MME) 114, and a packet data network gateway (PGW) 116. Generally speaking, the SGW 112 is configured to deliver user plane packets related to audio calls, video calls, Internet services, etc., and the MME 114 is configured to manage authentication, registration, paging, and other related functions. The PGW 116 provides connectivity from the UE 102 to one or more external packet data networks (e.g., an Internet network and / or an Internet Protocol (IP) Multimedia Subsystem (IMS) network). The 5GC 160 includes a user plane function (UPF) 162 and an access and mobility management function (AMF) 164 and / or a session management function (SMF) 166. Generally speaking, UPF 162 is configured to deliver user plane packets associated with audio calls, video calls, Internet services, etc., AMF 164 is configured to manage authentication, registration, paging and other related functions, and SMF 166 is configured to manage PDU sessions.

[0035] Location management function (LMF) 168 manages support for different location services for UEs, including positioning of the UE and delivery of assistance data to the UE. LMF 168 is interconnected with AMF 164 via an interface (e.g., NL1 interface). LMF 168 can interact with a base station (e.g., base station 104 or 106) of a UE (e.g., UE 102) to obtain location measurements of the UE, including uplink measurements made by the base station and downlink measurements made by the UE and provided to the base station. The LMF can interact with the UE to deliver assistance data to the UE for a particular location service (if requested by the UE), or to obtain a location estimate.

[0036] The LMF 168 may interact with a plurality of base stations (e.g., base stations 104 and 106) to provide assistance data information for broadcast. The assistance data information for broadcast may optionally be segmented and / or encrypted by the LMF 168. As described in more detail in TS 23.273, the LMF 168 may also interact with the AMF to provide encryption key data information to the AMF.

[0037] For positioning of the UE, LMF 168 decides one or more positioning methods to be used based on factors that may include the LCS client type, the required QoS, the UE positioning capabilities of the UE, and the positioning capabilities of the base station serving the UE. LMF 168 then invokes the positioning methods in the UE and / or the base station. The positioning methods may produce a position estimate of the UE-based positioning method and / or positioning measurements of the UE-assisted and network-based positioning methods. LMF 168 may combine all received results and determine a single position estimate of the UE (hybrid positioning). Additional information such as the accuracy of the position estimate and velocity may also be determined.

[0038] 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, so that UE 102 may select, reselect, or switch from one of cells 124 and 126 to another. In order to directly exchange messages or information, base station 104 and base station 106 may support an X2 or Xn interface. In general, CN 110 may be connected to any suitable number of base stations supporting NR cells and / or EUTRA cells.

[0039] The base station 104 is equipped with processing hardware 130, which may include one or more general-purpose processors (e.g., CPUs) and non-transitory computer-readable memory storing instructions, and the one or more general-purpose processors execute the instructions. In addition or alternatively, the processing hardware 130 may include a dedicated processing unit. In an example implementation, the processing hardware 130 includes a media access control (MAC) controller 132, which is configured to: perform a random access process with one or more user devices, receive an uplink MAC protocol data unit (PDU) of one or more user devices, and send a downlink MAC PDU to one or more user devices. The processing hardware 130 may also include a measurement gap controller 134, which is configured to manage measurement gaps for one or more UEs communicating with the base station 104. The processing hardware may further include an RRC controller 136 to implement processes and message delivery at the RRC sublayer of the protocol communication stack. In an example implementation, the processing hardware 130 includes an NRPPa controller 138, which is configured to manage communication with the LMF 168 via the NR Positioning Protocol A (NRPPa) to implement positioning and location services for one or more UEs. The base station 106 may include substantially similar components. In particular, the components 140, 142, 144, 146, and 148 of the base station 106 may be similar to the components 130, 132, 134, 136, and 138, respectively.

[0040] UE 102 is equipped with processing hardware 150, which may include one or more general-purpose processors such as CPUs and non-transitory computer-readable memory storing machine-readable instructions that can be executed on one or more general-purpose processors, and / or a dedicated processing unit. In an example implementation, the processing hardware 150 includes an RRC controller 156 configured to manage processes and message delivery at the RRC sublayer of the protocol communication stack. In an example implementation, the processing hardware 150 includes an LCS controller 158, which generates outbound (uplink) messages related to positioning, processes inbound (downlink) messages related to positioning, and performs various processes related to positioning. In an example implementation, the processing hardware 150 includes a media access control (MAC) controller 152, which is configured to perform a random access process with a base station, send uplink MAC protocol data units (PDUs) and / or control elements to the base station, and receive downlink MAC PDUs and / or control elements from the base station. The processing hardware 150 may also include a measurement gap controller 154 configured to manage measurement gaps configured by the RAN 105. The processing hardware may further include an RRC controller 156 to implement procedures and messaging at the RRC sublayer of the protocol communication stack.

[0041] Figure 1BAn example distributed or decentralized implementation of any one or more of the base stations 104, 106 is depicted. In this implementation, the base stations 104, 106 include a central unit (CU) 172 and one or more distributed units (DU) 174. The CU 172 includes processing hardware, such as one or more general-purpose processors (e.g., CPUs) and a computer-readable memory storing machine-readable instructions executable on the general-purpose processors, and / or a dedicated processing unit. For example, the CU 172 may include a PDCP controller, an RRC controller, and / or an RRC inactive controller, such as the PDCP controllers 134, 144, the RRC controllers 136, 146, and / or the RRC inactive controllers 138, 148. In some implementations, the CU 172 includes a radio link control (RLC) controller configured to manage or control one or more RLC operations or processes. In further implementations, the CU 172 does not include an RLC controller.

[0042] 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 one or more general-purpose processors, and / or dedicated processing units. For example, the processing hardware may include: a MAC controller (e.g., MAC controllers 132, 142) configured to manage or control one or more MAC operations or processes (e.g., random access processes); and / or an RLC controller configured to manage or control one or more RLC operations or processes. The processing hardware may also include a physical layer controller configured to manage or control one or more physical layer operations or processes.

[0043] In some embodiments, the RAN 105 supports integrated access and backhaul (IAB) functionality. In some implementations, the DU 174 operates as an (IAB) node and the CU 172 operates as an IAB donor.

[0044] In some implementations, the CU 172 includes a logical node CU-CP 172A that hosts a control plane portion of a PDCP protocol of the CU 172. In further implementations, the CU 172 includes a logical node CU-UP 172B that hosts a user plane portion of a PDCP protocol and / or a Service Data Adaptation Protocol (SDAP) protocol of the CU 172. Depending on the implementation, the CU-CP 172A sends control information (e.g., RRC messages, F1 application protocol messages), and the CU-UP 172B sends data packets (e.g., SDAPPDUs or Internet Protocol packets).

[0045] CU-CP 172A may be connected to multiple CU-UPs 172B via an E1 interface. CU-CP 172A selects an appropriate CU-UP 172B for the requested service of UE 102. In some implementations, a single CU-UP 172B is connected to multiple CU-CPs 172A via an E1 interface. CU-CP 172A may be connected to one or more DUs 174 via an F1-C interface. CU-UP 172B may be connected to one or more DUs 174 via an F1-U interface under the control of the same CU-CP 172A. In some implementations, one DU 174 is connected to multiple CU-UPs 172B under the control of the same CU-CP 172A. In such implementations, CU-CP 172A establishes connectivity between CU-UP 172B and DU 174 by using a Bearer Context Management function.

[0046] Figure 2A An example protocol stack 200 is illustrated in a simplified manner, according to which a UE 102 may communicate with an eNB / ng-eNB or gNB (e.g., one or more of base stations 104, 106).

[0047] In the example stack 200, the physical layer (PHY) 202A of EUTRA provides transport channels to the EUTRA MAC sublayer 204A, which in turn provides logical channels to the EUTRA RLC sublayer 206A. The EUTRA RLC sublayer 206A in turn provides RLC channels to the EUTRA PDCP sublayer 208 and, in some cases, to the NR PDCP sublayer 210. Similarly, the NR PHY 202B provides transport channels to the NR MAC sublayer 204B, which in turn provides logical channels to the NR RLC sublayer 206B. The NR RLC sublayer 206B in turn provides data delivery services to the NR PDCP sublayer 210. In some implementations, the NR PDCP sublayer 210 then provides data to the Service Data Adaptation Protocol (SDAP) 212 or the Radio Resource Control (RRC) sublayer ( Figure 2A (not shown) provides data transfer services. In some implementations, such as Figure 2A As shown, UE 102 supports both EUTRA and NR stacks to support switching between EUTRA and NR base stations and / or support DC implemented through EUTRA and NR interfaces. Figure 2A As shown, the UE 102 can support the layering of NR PDCP 210 above the EUTRA RLC 206A, and the layering of SDAP sublayer 212 above the NR PDCP sublayer 210.

[0048] The EUTRA PDCP sublayer 208 and the NR PDCP sublayer 210 receive packets, which may be referred to as service data units (SDUs) (e.g., from an Internet Protocol (IP) layer layered directly or indirectly on the PDCP layer 208 or 210), and output packets, which may be referred to as protocol data units (PDUs) (e.g., to the RLC layer 206A or 206B). For simplicity, this disclosure refers to both SDUs and PDUs as "packets", except where the difference between SDUs and PDUs is relevant.

[0049] In some implementations, for example, on the control plane, the EUTRA PDCP sublayer 208 and the NR PDCP sublayer 210 provide a signaling radio bearer (SRB) or an RRC sublayer ( Figure 2A In the embodiment of the present invention, the EUTRA PDCP sublayer 208 and the NR PDCP sublayer 210 may be used to exchange RRC messages, non-access stratum (NAS) messages, or LPP messages. In a further implementation, on the user plane, the EUTRA PDCP sublayer 208 and the NR PDCP sublayer 210 provide data radio bearers (DRBs) to support data exchange. The data exchanged on the NR PDCP sublayer 210 may be SDAP PDUs, Internet Protocol (IP) packets, or Ethernet packets.

[0050] Figure 2B An example protocol stack 250 is shown in a simplified manner, via which the UE 102 can communicate with a DU (e.g., DU 174) and a CU (e.g., CU 172). The radio protocol stack 200 is functionally divided, such as Figure 2B 206B, NR MAC 204B, and NR PHY 202B) are delegated to the DU. To support the connection to the 5GC, the NR PDCP 210 provides SRBs to the RRC 214, and the NR PDCP 210 provides DRBs to the SDAP 212 and SRBs to the RRC 214.

[0051] Reference now Figure 2CIn a known wireless communication system, the UE and the gNB / ng-eNB support a physical layer (PHY) 202 of EUTRA or NR. The PHY layer 202 provides a transport channel to a medium access control (MAC) 204 sublayer, which in turn provides a logical channel to a radio link control (RLC) sublayer 206, and the RLC sublayer provides an RLC channel to a packet data convergence protocol (PDCP) sublayer 210. The PDCP sublayer 210 provides a signaling radio bearer (SRB) and / or a data radio bearer (DRB) to the radio resource control (RRC) sublayer 210.

[0052] The UE exchanges messages of the non-access stratum (NAS) sublayer 216 with the AMF operating in the core network via the gNB / ng-eNB, and the UE exchanges messages of the LPP layer 218 with the LMF also operating in the core network via the gNB / ng-eNB and the AMF. In other words, the UE and the LMF encapsulate the LPP message in the NAS message, and the NAS message in the RRC message. The gNB / ng-eNB according to the architecture provides tunnels to layers 216 and 218, and does not route or otherwise process messages at layers 216, 218.

[0053] Next, refer to FIG. 3A to FIG. 5C Discussion Figure 1A and several example scenarios related to sending data in an inactive or idle state. FIG. 3A to FIG. 5C Similar events in the Figure 3A Event 302 in Figure 3B To event 302 in FIG. 3G, FIG. 4A to FIG. 4C Event 402 in and FIG. 5A to FIG. 5C ), with differences discussed below where appropriate. In addition to the differences shown in the figures and discussed below, any alternative implementation discussed for a particular event (e.g., for message delivery and processing) can be applied to events marked with similar reference numbers in other figures, and can also be applied to both integrated and distributed base stations.

[0054] In order to simplify the following description, an “inactive state” is used and may refer to an RRC_INACTIVE or RRC_IDLE state, and a “connected state” is used and may refer to an RRC_CONNECTED state.

[0055] First reference Figure 3A, which illustrates a scenario 300A in which a base station 104 includes a central unit (CU) 172 and a distributed unit (DU) 174. Depending on the implementation, the DU 174 operates one or more transmission-reception points (TRPs) ( Figure 3A 300). In the scenario 300, the UE 102 initially operates in a connected state 302 and communicates 304 with the DU 174, such as by using a DU configuration. While communicating 304 with the DU 174, the UE 102 receives an uplink grant and a downlink allocation from the DU 174 using a cell radio network temporary identifier (C-RNTI). The UE 102 sends UL data to the DU 174 using the uplink grant and receives DL data from the DU 174 using the downlink allocation. The UE 102 further communicates 304 with the CU 172 via the DU 174 by using a CU configuration. The UE 102 communicates 304 LPP messages with the LMF 168 via the CU 172 and the DU 174. In some implementations, the CU 172 exchanges LPP messages with the LMF 168 directly or via the AMF 164. Depending on the implementation, before or during the communication 304 between the UE and the base station 104, the LMF 68 performs 306 a TRP Information Exchange process with the base station 104 to obtain detailed information of the TRP hosted by the base station 104.

[0056] In some implementations, the LMF 168 sends a TRP Information Request message (i.e., an LMF to BS message or an NRPPa message) to the CU 172 to perform the TRP information exchange process. In response to or after receiving the LMF to BS message, the CU 172 sends at least one TRP Information Request message (i.e., a CU to DU message or an F1AP message) to the DU 174 to request the DU 174 to provide detailed information of the TRP hosted by the DU 174. In response to each of the CU to DU messages, the DU 174 sends a TRP Information Response message (i.e., a DU to CU message or an F1AP message) including TRP information of the specific TRP to the CU 172. In some implementations, the CU 172 sends a TRP Information Response message (i.e., a DU to CU message or an F1AP message) to the other DUs ( Figure 3AIn response to each of the at least one CU-to-DU message received by a specific DU among the other DUs, the specific DU sends a TRP information response message (i.e., a DU-to-CU message or an F1AP message) including TRP information of the specific TRP to CU 172.

[0057] After receiving all messages in at least one DU-to-CU message from DU 174 and / or other DUs, CU 172 sends a BS-to-LMF message (e.g., a TRP information response message) including the TRP information received from DU 174 and / or other DUs to LMF 168. In some implementations, the TRP information for a particular TRP includes a positioning reference signal (PRS) configuration, a physical cell identity (PCI), and / or a cell global identifier (CGI). In some implementations, the DU-to-CU message includes a TRPID for a particular TRP and the TRP information for the TRP, and CU 172 includes the TRP ID and the TRP information in a BS-to-LMF message.

[0058] After performing 306 the TRP information exchange procedure, the LMF 168 sends 308 a request for measurement preconfiguration message (i.e., an LMF to BS message or an NRPPa message) to the CU 172 to request configuration of measurement gaps for the UE 102 to measure the PRS transmitted by the TRP. In some implementations, the LMF 168 includes TRP PRS information items (e.g., TRP-PRS-Information-List-Item IE) in the request for measurement preconfiguration message at event 308. In some implementations, each of the TRP PRS information items includes a PRS configuration, PCI, CGI, and / or TRP ID of a specific TRP among the TRPs operated by the DU 174. In some implementations, the LMF 168 determines the TRP PRS information items based on at least one DU to CU message (e.g., TRP ID and TRP information) of the TRP information exchange procedure.

[0059] After or in response to receiving 308 the message, the CU 172 sends 310 a Measurement Preconfiguration Required message (i.e., a CU to DU message or a F1AP message) including a TRP PRS information item to the DU 174 to request configuration of measurement gaps for the UE 102. In response, the DU 174 sends 312 a Measurement Preconfiguration Confirm message (i.e., a DU to CU message or a F1AP message) to the CU 172 to confirm configuration of measurement gaps for the UE 102. After or in response to receiving 312 the Measurement Preconfiguration Confirm message, the DU 174 sends 314 a UE Context Modification Required message including a gap configuration for the UE 102 to the CU 172. The gap configuration configures measurement gaps for the UE 102 to measure the PRS transmitted by the TRP. In some implementations, the DU 174 generates the gap configuration based on the TRP PRS information item. In some implementations, the DU 174 generates the gap configuration as an RRC IE (e.g., a GapConfig IE or a GapConfig-r17 IE). In some implementations, the DU 174 generates a measurement gap configuration (e.g., a MeasGapConfig IE) including the gap configuration (e.g., the GapConfig IE or the GapConfig-r17 IE), and includes the measurement gap configuration in the Require UE Context Modification message. In some implementations, in each of the gap configurations, the DU 174 includes a preconfiguration indicator (e.g., a preConfigInd field) indicating that the gap configuration is a preconfigured gap configuration. In such a case, the DU 174 determines that the gap configuration including the preconfiguration indicator is initially deactivated. For the gap configuration not including the preconfiguration indicator, the DU 174 determines that the gap configuration is initially activated. In some implementations, in each of the gap configurations, the DU 174 includes an indicator (e.g., a gapAssociationPRS field) indicating that the gap configuration is associated with a PRS measurement. In some implementations, the DU 174 sends 314 a UE context modification required message before or after sending 312 a measurement preconfiguration confirm message.

[0060] In some implementations, the DU 174 does not include the gap configuration as an interface IE (e.g., F1AP IE) in the measurement preconfiguration confirmation message. In some such implementations, the gap configuration is transparent to the CU 172. In other implementations, the DU 174 includes at least some of the gap information as an interface IE (e.g., F1AP IE) in the measurement preconfiguration confirmation message. In some such implementations, the gap configuration is opaque to the CU 172.

[0061] In response to receiving 314 the UE context modification required message or after receiving 314 the UE context modification required message, the CU 172 sends 316 a UE context modification confirm message to the DU 174. After receiving 312 the measurement preconfiguration confirm message, receiving 314 the UE context modification required message, or sending 316 the UE context modification confirm message, the CU 172 sends 318 a measurement preconfiguration confirm message (i.e., a BS to LMF message or an NRPPa message) to the LMF 168 to confirm the configuration of the measurement gaps for the UE 102.

[0062] In some implementations, DU 174 assigns a gap ID to each of the gap configurations. In some implementations, DU 174 includes the gap ID in the corresponding gap configuration. In other implementations, DU 174 includes the gap ID in the measurement gap configuration and the gap configuration. In some implementations, DU 174 associates the gap ID and / or the corresponding gap configuration with the TRP PRS information item. In some implementations, DU 174 associates a specific gap ID and / or the corresponding gap configuration with a specific one of the TRP PRS information items. In other implementations, DU 174 associates a specific gap ID and / or the corresponding gap configuration with some of the TRP PRS information items. In yet other implementations, DU 174 associates a specific gap ID and / or the corresponding gap configuration with a specific one of the TRP PRS information items. In some implementations, DU 174 creates a table to store the association between the gap ID and the TRP PRS information item.

[0063] In other implementations, CU 172 assigns a gap ID to each of the gap configurations. In some implementations, CU 172 includes the gap ID in the corresponding gap configuration. In other implementations, CU 172 includes the gap ID in the measurement gap configuration and the gap configuration. In some implementations, CU 172 associates the gap ID and / or the corresponding gap configuration with the TRP PRS information item. In some implementations, CU 172 associates a specific gap ID and / or the corresponding gap configuration with a specific one of the TRP PRS information items. In other implementations, CU 172 associates a specific gap ID and / or the corresponding gap configuration with some of the TRP PRS information items. In yet other implementations, CU 172 associates a specific gap ID and / or the corresponding gap configuration with a specific one of the TRP PRS information items. In some implementations, CU 172 creates a table to store the association between the gap ID and the TRP PRS information item.

[0064] Events 310, 312, 314, and 316 are Figure 3A This is collectively referred to as the gap (pre) configuration process 392A.

[0065] After receiving the gap configuration or the measurement gap configuration, the CU 172 generates an RRC reconfiguration message (e.g., an RRCReconfiguration message) including the gap configuration or the measurement gap configuration, and sends 320 a CU-to-DU message (e.g., a DL RRC Message Transfer message) including the RRC reconfiguration message to the DU 174. In turn, the DU 174 sends 322 the RRC reconfiguration message to the UE 102. In response, the UE 102 sends 324 an RRC reconfiguration complete message (e.g., an RRCReconfigurationComplete message) to the DU 174, which in turn sends 326 a DU-to-CU message (e.g., an UL RRC Message Transfer message) including the RRC reconfiguration complete message to the CU 172. To include the gap configuration or the measurement gap configuration in the RRC reconfiguration message, in some implementations, the CU 172 generates a measurement configuration (e.g., a MeasConfig IE) including the measurement gap configuration, and includes the measurement configuration in the RRC reconfiguration message. In the event that the gap configuration includes a pre-configuration indicator, the UE 102 determines that the gap configuration including the indicator is initially deactivated.

[0066] Events 320, 322, 324, and 326 are Figure 3A394. Events 308, 310, 312, 314, 316, 318, 320, 322, 324, and 326 are collectively referred to as RRC reconfiguration process 394. Figure 3A In some implementations, similar to the measurement gap configuration procedure 390A, an additional measurement gap configuration procedure is performed to configure an additional gap configuration for the UE 102.

[0067] In some implementations, later, the LMF 168 sends 328 a measurement activation message (i.e., an LMF to BS message or an NRPPa message) to the CU 172 to activate at least one of the deactivated gap configurations. In some implementations, the measurement activation message of event 328 includes PRS measurement information (e.g., PRS-Measurements-Info-List-Item IE), each PRS measurement information including a reference point (e.g., pointA), a measured PRS period (e.g., measPRSPeriodicity), a measured PRS offset (e.g., measPRSOffset), and / or a measured PRS length (e.g., measurementPRSLength). In further implementations, in response to or after receiving 328 the measurement activation message, the CU 172 sends 330 a measurement activation message (i.e., a CU to DU message or an F1AP message) to the DU 174 to activate at least one of the gap configurations of the UE 102. In some implementations, the measurement activation message of event 330 includes PRS measurement information (e.g., PRS-Measurements-Info-List-Item IE), each PRS measurement information including a reference point (e.g., pointA), a measured PRS period (e.g., measPRSPeriodicity), a measured PRS offset (e.g., measPRSOffset), and / or a measured PRS length (e.g., measurementPRSLength). The PRS measurement information items of event 328 may be similar or identical to the PRS measurement information items of event 330.

[0068] Depending on the implementation, in response to or after receiving 330 the measurement activation message, the DU 174 sends 332 a measurement gap activation command to the UE 102 to activate at least one of the gap configurations. In some scenarios or implementations, if the CU 172 receives an RRC message (e.g., a LocationMeasuementIndication message) from the UE 102 requesting a measurement gap, the CU 172 sends 330 the measurement activation message to the DU 174 in response to or after receiving the RRC message. In other scenarios or implementations, the CU 172 sends 330 the measurement activation message to the DU 174 in response to or after receiving an LMF to BS message (e.g., the measurement preconfiguration message 308 required) other than the measurement activation message of event 328. In some implementations, the measurement gap activation command is a DL MAC control element (e.g., a positioning measurement gap activation / deactivation command MAC control element). In such implementations, the DU 174 generates a DL MAC PDU including a DL MAC Control element and a subheader of the DL MAC Control element, and transmits 332 the DL MAC PDU to the UE 102. In some implementations, the subheader includes a logical channel ID specific to the measurement gap activation command.

[0069] Alternatively, the UE 102 sends 329 a measurement gap activation request to the DU 174 to request activation of at least one of the gap configurations. In some implementations, in response to or after receiving 329 the measurement gap activation request, the DU 174 sends 332 a measurement gap activation command to the UE 102. In some implementations, the measurement gap activation request is a UL MAC control element (e.g., a positioning measurement gap activation / deactivation request MAC control element). In such implementations, the UE 102 generates a UL MAC PDU including the UL MAC control element and a subheader of the UL MAC control element, and sends 329 the UL MAC PDU to the DU 174. In some implementations, the subheader includes a logical channel ID specific to the UL MAC control element. In the measurement gap activation request, in some implementations, the UE 102 includes at least one gap ID indicating the gap configuration that the UE 102 requests activation. In other implementations, the UE 102 does not include a gap ID in the measurement gap activation request in order to request activation of all gap configurations. In still other implementations, the UE 102 includes a specific field (rather than all gap IDs) with a specific value in the measurement gap activation request in order to request activation of all gap configurations.

[0070] In some implementations, the DU 174 includes at least one gap ID in the measurement gap activation command indicating the gap configuration to be activated. In some implementations, the DU 174 determines (e.g., identifies, selects, or derives) at least one gap ID based on the TRP PRS information items and / or associations received at event 330. In some implementations, the DU 174 performs a table lookup to determine at least one gap ID based on the TRP PRS information items received at event 330. In some cases, such as receiving 329 the measurement gap activation request, the DU 174 sets the at least one gap ID in the measurement gap activation command to the value of the gap ID in the measurement gap activation request.

[0071] In some implementations, the DU 174 does not include a gap ID in the measurement gap activation command in order to activate all gap configurations. In further implementations, the UE 102 includes a specific field with a specific value in the measurement gap activation request (instead of including all gap IDs) to request activation of all gap configurations.

[0072] In some implementations, after sending a measurement gap activation command to the UE 102 or receiving a measurement gap activation request from the UE 102, the DU 174 sends 334 a DU to CU message to the CU 172, the DU to CU message including a measurement gap status indicating a status of the gap configuration (e.g., activated or deactivated). Thus, the CU 172 determines from the measurement gap status that the UE 102 activates at least one of the gap configurations and / or starts performing measurements on the PRS transmitted by the TRP. In some implementations, the CU 172 sends 336 a BS to LMF message including the measurement gap status to the LMF 168. Thus, the LMF 168 determines from the measurement gap status that the UE 102 activates the gap configuration and / or starts performing measurements on the PRS transmitted by the TRP.

[0073] Events 328, 330, 329, 332, 334, and 336 are Figure 3A The additional measurement gap activation process 396 is collectively referred to as the measurement gap activation process 396. In some implementations, similar to the measurement gap activation process 396, an additional measurement gap activation process is performed to activate the additional gap configuration or the additional measurement gap configuration process configured in the process 390A.

[0074] In response to or after receiving 332 the measurement gap activation command, the UE 102 activates 338 at least one gap configuration identified by at least one gap ID in the measurement gap activation command. After activating the gap configuration, the UE 102 performs 338 measurement on the PRS transmitted by the TRP using the gaps in the activated gap configuration. In some implementations, the UE 102 obtains measurement results from the measurement and sends 340 the measurement results to the LMF 168 via the base station 104 (i.e., the DU 174 and the CU 172). In some implementations, the UE 102 generates an LPP message (e.g., a ProvideLocationInformation message) including the measurement results and sends 340 the LPP message to the LMF 168 via the base station 104.

[0075] In some implementations, the CU configuration includes configuration parameters in a RadioBearerConfig information element (IE) and / or a MeasConfig IE (e.g., as defined in 3GPP specification 38.331 version 16.7.0 or higher). In some implementations, the CU configuration is or includes the RadioBearerConfig IE and / or the MeasConfig IE, and the second CU configuration is or includes the RadioBearerConfig IE and / or the MeasConfig IE. In some implementations, the DU configuration includes configuration parameters related to the operation of the RRC, RLC, MAC, and / or PHY protocol layers (e.g., RLC 206B, MAC 204B, and / or PHY 202B), which the UE 102 and the DU 174 use to communicate with each other when the UE 102 operates in a connected state. In some implementations, the DU configuration includes configuration parameters in a CellGroupConfig IE (e.g., as defined in 3GPP specification 38.331 version 16.7.0). In some implementations, the DU configuration is the CellGroupConfig IE.

[0076] In some implementations, if the DU 174 has not yet activated the gap configuration for the UE 102 (i.e., the DU 174 has not yet sent a measurement gap activation command to the UE 102 to activate the gap configuration), the DU 174 schedules a DL transmission or an UL transmission for the UE 102 in a time slot within the gap configured in the gap configuration. Since the UE 102 has not yet activated the gap configuration (i.e., the UE 102 has not yet received a measurement gap activation command from the DU 174 to activate the gap configuration), the UE 102 monitors the PDCCH in a time slot within the gap configured in the gap configuration. For example, the DU 174 generates DL control information (DCI) for the DL transmission, generates a CRC for the DCI, scrambles the CRC with the C-RNTI, and sends the DCI and the scrambled CRC on the PDCCH in a time slot within the measurement gap configured in the gap configuration. The UE 102 receives the DCI and the scrambled CRC on the PDCCH in the time slot.

[0077] If DU 174 has activated the gap configuration for UE 102 (i.e., DU 174 has sent a measurement gap activation command for activating the gap configuration to UE 102), DU 174 avoids scheduling DL transmissions or UL transmissions for UE 102 in time slots within the gaps configured in the gap configuration. Since UE 102 has activated the gap configuration (i.e., UE 102 has received a measurement gap activation command for activating the gap configuration from DU 174), UE 102 avoids monitoring the PDCCH in time slots within the gaps configured in the gap configuration.

[0078] Next reference Figure 3B , scenario 300B is substantially similar to scenario 300A, except that CU 172 sends 315 a UE context modification request message to DU 174 to request a gap configuration, and DU 174 sends 317 a UE context modification response message including the gap configuration in response. In scenario 300B, DU 174 refrains from sending a UE context modification required message including the gap configuration to CU 172. In some implementations, after sending 310 a measurement preconfiguration required message, CU 172 sends 315 a UE context modification request message to DU 174.

[0079] In some implementations, CU 172 includes in the UE context modification request message an indication instructing DU 174 to generate a gap configuration for positioning measurements. In response to the indication, DU 174 generates a gap configuration based on the TRP PRS information item and includes the gap configuration in the UE context modification response message. In other implementations, the UE context modification request message does not include the indication. In some such implementations, CU 172 sends the UE context modification request message immediately after sending 310 the measurement preconfiguration required message, so that DU 174 can associate the UE context modification request message with the measurement preconfiguration required message.

[0080] In some implementations, the DU 174 generates a measurement gap configuration IE (eg, MeasGapConfig IE) including a gap configuration (eg, GapConfig IE or GapConfig-r17 IE), and includes the measurement gap configuration in a UE Context Modification Response message.

[0081] Events 310, 312, 315, and 317 are Figure 3B Events 308, 310, 312, 315, 317, 318, 320, 322, 324, and 326 are collectively referred to as gap (pre) configuration process 392B. Figure 3B The process is collectively referred to as the measurement gap configuration process 390B.

[0082] Next reference Figure 3C , scenario 300C is substantially similar to scenarios 300A and 300B, except that DU 174 sends 313 a measurement preconfiguration confirm message including a gap configuration in response to the measurement preconfiguration required message of event 310. In scenario 300C, DU 174 refrains from sending a UE context modification required message including a gap configuration to CU 172.

[0083] In some implementations, the DU 174 generates a measurement gap configuration IE (eg, a MeasGapConfig IE) including a gap configuration (eg, a GapConfig IE or a GapConfig-r17 IE), and includes the measurement gap configuration in a MeasurementPreconfigurationConfirm message at event 313 .

[0084] Events 310 and 313 in Figure 3C Events 308, 310, 313, 318, and 394 are collectively referred to as the gap (pre) configuration process 392C. Figure 3C This is collectively referred to as the measurement gap configuration process 390C.

[0085] Next reference Figure 3D, scene 300D is substantially similar to scenes 300A to 300C. The differences between scene 300D and scenes 300A to 300C are discussed below.

[0086] In scenario 300D, events 304, 306, 390A / 390B / 390C, 396, 338, and 340 are Figure 3D388. In some implementations, after the positioning measurement process 388, the LMF 168 sends 342 an LMF to BS message to the CU 172, causing the CU 172 to deactivate at least one of the activated gap configurations. In some implementations, the LMF to BS message is a new NRPPa message (e.g., a Measurement Deactivation message). In other implementations, the LMF to BS message is an existing NRPPa message (e.g., a Measurement Suspension message). In response to or after receiving the LMF to BS message, the CU 172 sends 344 a CU to DU message to the DU 174, causing the DU 174 to deactivate at least one of the activated gap configurations. In response to or after receiving the CU to DU message, the DU 174 sends 348 a Measurement Gap Deactivation Command to the UE 102 to deactivate at least one of the activated gap configurations. In some implementations, the measurement gap deactivation command is a DL MAC control element (e.g., a positioning measurement gap activation / deactivation command MAC control element). In such implementations, the DU 174 generates a DL MAC PDU including a DL MAC control element and a subheader of the DL MAC control element, and sends 348 the DL MAC PDU to the UE 102. In some implementations, the subheader includes a logical channel ID specific to the measurement gap deactivation command. In other implementations, the subheader includes a logical channel ID that is the same as the subheader of the measurement gap activation command. In some such implementations, the measurement gap activation command and the measurement gap deactivation command use the same DL MAC control element format. In some implementations, the format includes a field indicating the number of gap configurations to be activated or deactivated. In some implementations, the format includes a single field having a first value or a second value indicating that the DL MAC control element format is a measurement gap activation command or a measurement gap deactivation command. The first value indicates that the DL MAC control element format is a measurement gap activation command. The second value indicates that the DL MAC control element format is a measurement gap deactivation command. In other implementations, the format includes a field for each gap configuration included in the DL MAC control element format. The first value of the field indicates "activation" of the gap configuration, and the second value indicates "deactivation" of the gap configuration. In some such implementations, the DL MAC control element format activates some gap configurations and deactivates other gap configurations.

[0087] In some implementations, CU 172 does not include information in the CU-to-DU message at event 344 that DU 174 can use to derive which gap configuration(s) to deactivate. In such implementations, DU 174 deactivates all activated gap configurations for UE 102 in response to the CU-to-DU message at event 344. In other implementations, CU 172 includes information (e.g., a PRS measurement information item) in the CU-to-DU message at event 344 that DU 174 can use to derive which gap configuration(s) to deactivate.

[0088] In some implementations, the CU to DU message of event 344 is a new F1AP message (e.g., a measurement deactivation message). In other implementations, the CU to DU message of event 344 is an existing F1AP message (e.g., a measurement preconfiguration termination message). In yet other implementations, the CU to DU message of event 344 is a measurement activation message, including a deactivation indication and / or not including a PRS measurement information item (e.g., a PRS-Measurements-Info-List-Item IE). In such implementations, the measurement activation message is considered a measurement deactivation message. In yet other implementations, the CU to DU message of event 344 is a measurement activation message, which includes a PRS measurement information item (e.g., a PRS-Measurements-Info-List-Item IE) and a deactivation indication for each of the PRS measurement information items.

[0089] Alternatively, the UE 102 sends 346 a measurement gap deactivation request to the DU 174 to request deactivation of at least one of the activated gap configurations. Depending on the implementation, in response to receiving 346 the measurement gap deactivation request or after receiving 346 the measurement gap deactivation request, the DU 174 sends 348 a measurement gap deactivation command to the UE 102. In some implementations, the measurement gap deactivation request is a UL MAC control element (e.g., a positioning measurement gap activation / deactivation request MAC control element). In such implementations, the UE 102 generates a UL MAC PDU including the UL MAC control element and a subheader of the UL MAC control element, and sends 346 a UL MAC PDU to the DU 174. In some implementations, in the measurement gap deactivation request, the UE 102 includes a gap ID indicating the activated gap configuration that the UE 102 requests to deactivate. In some implementations, the subheader includes a logical channel ID specific to the measurement gap deactivation request. In other implementations, the subheader includes a logical channel ID (e.g., which is the same as the subheader of the measurement gap activation request). In some such implementations, the measurement gap activation request and the measurement gap deactivation request use the same UL MAC control element format. In some implementations, the format includes a field indicating the number of gap configurations to be requested to be activated or deactivated. In some implementations, the format includes a single field having a first value or a second value indicating whether the UL MAC control element format is a measurement gap activation request or a measurement gap deactivation request. The first value indicates that the UL MAC control element format is a measurement gap activation request. The second value indicates that the UL MAC control element format is a measurement gap deactivation request. In other implementations, the format includes a field for each gap configuration included in the UL MAC control element format. The first value of the field indicates an "activation request" for the gap configuration, and the second value indicates a "deactivation request" for the gap configuration. In some such implementations, the DL MAC control element format requests activation of some gap configurations and deactivation of other gap configurations.

[0090] In some implementations, the DU 174 includes in the measurement gap deactivation command a gap ID indicating the gap configuration to be deactivated. In some implementations, the DU 174 determines the gap ID based on the PRS measurement information item (if included) included in the CU-to-DU message of event 344. In some implementations, the DU 174 performs (e.g., as for Figure 3A In some cases, such as when receiving 346 a measurement gap deactivation request, the DU 174 sets the gap ID in the measurement gap deactivation command to the value of the gap ID in the measurement gap deactivation request.

[0091] In some implementations, after or in response to sending 348 the measurement gap deactivation command to the UE 102, the DU 174 sends 350 a DU to CU message to the CU 172, the DU to CU message including a measurement gap status indicating that the gap configuration of the UE 102 is deactivated. Thus, the CU 172 determines from the measurement gap status that the UE 102 deactivates the gap configuration and / or stops performing measurements on the PRS sent by the TRP. In some implementations, the DU to CU message of event 350 is an existing F1AP message (e.g., as defined in 3GPP specification 38.473). In other implementations, the DU to CU message is a new F1AP message (e.g., a measurement status message or a measurement gap status message). In some cases where some gap configurations of the UE 102 are still activated, the measurement gap status includes the state of the gap configuration (i.e., activated).

[0092] In some implementations, CU 172 sends 352 a BS-to-LMF message including the measurement gap status to LMF 168. Thus, LMF 168 determines from the measurement gap status that UE 102 deactivates the gap configuration and / or stops performing measurements on the PRS sent by the TRP. In some implementations, the BS-to-LMF message of event 352 is an existing NRPPa message (e.g., as defined in 3GPP specification 38.455). In other implementations, the BS-to-LMF message is a new NRPPa message (e.g., a measurement status message or a measurement gap status message).

[0093] Events 342, 344, 346, 348, 350, and 3752 Figure 3D This is collectively referred to as the measurement gap deactivation process 398.

[0094] Later, depending on the implementation, the LMF 168, the CU 172, and / or the DU 174 perform 395 a measurement gap activation procedure with the UE 102 to activate the deactivated gap configuration. In some implementations, in response to the measurement gap activation procedure 395, the UE 102 activates 339 the gap configuration identified by the gap ID in the measurement gap activation command in the procedure 395. After activating the gap configuration, the UE 102 performs 339 measurement on the PRS sent by the TRP using the gaps in the activated gap configuration. In some implementations, the UE 102 obtains a measurement result from the measurement and sends 341 the measurement result to the LMF 168 via the base station 104 (i.e., the DU 174 and the CU 172). In some implementations, the UE 102 generates an LPP message (e.g., a ProvideLocationInformation message) including the measurement result and sends 341 the LPP message to the LMF 168 via the base station 104.

[0095] Next reference Figure 3E , scene 300E is substantially similar to scenes 300A to 300D. The differences between scene 300E and scenes 300A to 300D are discussed below.

[0096] In some implementations, after the positioning measurement process 388, the LMF 168 sends 343 an LMF to BS message to the CU 172, causing the CU 172 to release the gap configuration. In some implementations, the LMF to BS message is an existing NRPPa message (e.g., as defined in 3GPP specification 38.455). For example, the LMF to BS message is a measurement preconfiguration required message, a measurement abort message, or an error indication (Error Indication) message. In other implementations, the LMF to BS message is a new NRPPa message. For example, the LMF to BS message is a measurement deactivation message, a measurement preconfiguration release required (MeasurementPreconfiguration Release Required) message, or a measurement preconfiguration release request (MeasurementPreconfiguration Release Request) message.

[0097] In response to receiving 343 to the LMF to BS message or after receiving 343 to the LMF to BS message, CU 172 sends 345 CU to DU message to DU 174, thereby causing DU 174 to release at least one of the gap configurations. In response to receiving 345 to the CU to DU message or after receiving 345 to the CU to DU message, DU 174 releases at least one of the gap configurations of UE 102. In other implementations, the CU to DU message is an existing F1AP message (e.g., as defined in 3GPP specification 38.473). For example, the CU to DU message is a positioning measurement abort message, a measurement preconfiguration request message, or a UE context modification request message. In other implementations, the CU to DU message is a new F1AP message (e.g., a measurement deactivation message, a measurement preconfiguration release request message, or a measurement preconfiguration release request message). Depending on the implementation, DU 174 sends 347 DU to CU message to CU 172 in response to the CU to DU message. In some implementations, the DU-to-CU message of event 347 is an existing F1AP message (eg, a Measurement Preconfiguration Confirm message or a UE Context Modification Response message).

[0098] In response to or after receiving the LMF to BS message, CU 172 generates an RRC reconfiguration message (e.g., RRCReconfiguration message) that releases the gap configuration, and sends 321 a CU to DU message (e.g., DL RRC messaging message) including the RRC reconfiguration message to DU 174. DU 174 then sends 323 the RRC reconfiguration message to UE 102. In response to or after receiving 323 the RRC reconfiguration message, UE 102 releases the gap configuration.

[0099] In some implementations, the RRC reconfiguration message includes gap release information for releasing the gap configuration, the gap release information including a gap ID of at least one of the gap configurations. For example, the gap release information is a gap release list IE. In such implementations, the UE 102 identifies at least one of the gap configurations according to the gap ID, and releases the identified gap configuration in response to the RRC reconfiguration message or the gap release information. In some implementations, the CU 172 generates the gap release information and includes the gap release information in a CU-to-DU message of event 345. In such implementations, the DU 174 identifies the gap configuration according to the gap ID, and releases the identified gap configuration in response to the CU-to-DU message or the gap release information.

[0100] In response to the RRC reconfiguration message, UE 102 sends 325 an RRC reconfiguration complete message (e.g., an RRCReconfigurationComplete message) to DU 174, which in turn sends 327 a DU to CU message (e.g., an UL RRC messaging message) including the RRC reconfiguration complete message to CU 172. In some implementations, after receiving 327 the DU to CU message of event 327, CU 172 sends 353 a BS to LMF message to LMF 168 in response to the LMF to BS message of event 343. Alternatively, CU 172 sends 353 the BS to LMF message before receiving the DU to CU message of event 327.

[0101] In some implementations, CU 172 autonomously determines to release at least one of the gap configurations without receiving an LMF to BS message as event 343. In such implementations, CU 172 sends 345 a CU to DU message and / or sends 321 an RRC reconfiguration message to DU 174 in response to the determination.

[0102] In some implementations, later, LMF 168 , CU 172 , and / or DU 174 perform 389 a positioning measurement process with UE 102 , similar to process 388 .

[0103] In some implementations, after performing 388 the positioning measurement procedure and before receiving 343 a LMF to BS message or sending 345 a CU to DU message, the LMF 168, CU 172, and / or DU 174 performs 398 a measurement gap deactivation procedure.

[0104] Next reference Figure 3F , scenario 300F is substantially similar to scenarios 300A to 300E. The differences between scenario 300F and scenarios 300A to 300E are discussed below.

[0105] In scenario 300F, after or in response to receiving 345 the CU to DU message, DU 174 sends 354 a UE context modification required message including gap release information indicating release of the gap configuration. In response, CU 172 sends 356 a UE context modification confirmation message to DU 174. In some implementations, CU 172 includes the gap release information received from DU 174 in the RRC reconfiguration message. In some such implementations, CU 172 does not include the gap release information in the CU to DU message at event 345.

[0106] Next, refer to FIG. 4A to FIG. 8 Several example methods that can be implemented in a DU of a BS or a CU of a BS are discussed. Each of these methods can be implemented using processing hardware, such as one or more processors, to execute instructions stored on a non-transitory computer-readable medium, such as a computer memory.

[0107] First reference Figure 4A , method 400A is a method for configuring a measurement gap of a UE (eg, UE 102) and is implemented in a DU (eg, DU 174).

[0108] Method 400A begins at block 402, where a DU communicates with a UE and a CU (e.g., CU 172). At block 404, the DU receives a first CU-to-DU message from the CU requesting configuration of a measurement gap for the UE (e.g., event 310). At block 406, the DU sends a first DU-to-CU message to the CU in response to the first CU-to-DU message (e.g., event 312). In some implementations, the DU sends the first DU-to-CU message to the CU to confirm the successful configuration of the measurement gap. At block 408, the DU sends a second DU-to-CU message to the CU in response to the first CU-to-DU message (e.g., event 314), where M is an integer and greater than zero, including gap configurations 1, ..., M of the UE. At block 410, the DU receives a second CU-to-DU message from the CU in response to the second DU-to-CU message (e.g., event 316). At block 412, the DU sends a measurement gap activation command to the UE to activate at least one of the one or more gap configurations (e.g., event 332).

[0109] In some implementations, the first CU to DU message includes TRP PRS information items 1, ..., N, where N is an integer and greater than zero. In some implementations, the first CU to DU message does not include measurement object information (e.g., MeasObjectToAddModList IE or MeasObjectToAddMod IE). In some implementations, the DU generates a measurement gap configuration (e.g., MeasGapConfig IE) including gap configurations 1, ..., M (e.g., GapConfig IE or GapConfig-r17 IE 1, ..., M) and includes the measurement gap configuration in the second DU to CU message. In some implementations, the DU generates a gap configuration for positioning measurement (e.g., the UE uses the gaps in gap configurations 1, ..., M to measure PRS).

[0110] In some implementations, the DU assigns gap IDs 1, ..., M to gap configurations 1, ..., M, respectively. In some implementations, the DU includes gap IDs 1, ..., M in gap configurations 1, ..., M, respectively. In other implementations, the DU includes gap IDs 1, ..., M in measurement gap configurations and gap configurations 1, ..., M. In some implementations, the DU associates gap IDs 1, ..., M with TRP PRS information items 1, ..., N. In some implementations, the DU associates a specific one of the gap IDs with a specific one of the TRP PRS information items. In other implementations, the DU 174 associates a specific one of the gap IDs with some of the TRP PRS information items. In some implementations, the DU creates a table to store associations between gap IDs and TRP PRS information items.

[0111] In the measurement gap activation command, the DU includes at least gap IDs 1, ..., M. Each of the at least one gap ID identifies a specific one of at least one gap configuration of gap configurations 1, ..., M.

[0112] Figure 4B 4 is a flow chart of an example method 400B that is similar to method 400A, except that method 400B includes blocks 409 and 411 instead of blocks 408 and 410. At block 409, the DU receives a second CU-to-DU message from the CU requesting configuration of measurement gaps for the UE (e.g., event 315). At block 411, the DU sends a second DU-to-CU message including gap configurations 1, ..., M of the UE to the CU in response to the second CU-to-DU message (e.g., event 317).

[0113] Figure 4C is a flow chart of an example method 400C that is similar to method 400A, except that method 400C includes block 407 instead of blocks 406, 408, and 410. At block 407, the DU sends a first DU-to-CU message including gap configurations 1, ..., M of the UE to the CU in response to the first CU-to-DU message to confirm successful configuration of the measurement gap (e.g., event 313).

[0114] In some implementations, the DU generates a measurement gap configuration (eg, a MeasGapConfig IE) including gap configurations 1, ..., M (eg, a GapConfig IE or a GapConfig-r17 IE 1, ..., M) and includes the measurement gap configuration in a first DU to CU message.

[0115] In previous figures (e.g., FIG. 3A to FIG. 3F The examples and implementations described in ) can be applied to FIG. 4A to FIG. 4C .

[0116] New reference Figure 5A , method 500A is a method for configuring a measurement gap of a UE (eg, UE 102) and is implemented in a CU (eg, CU 172).

[0117] Method 500A begins at block 502, where a CU communicates with a UE and a DU (e.g., DU 174). At block 504, the CU sends a first CU-to-DU message to the DU requesting configuration of a measurement gap for the UE (e.g., event 310). At block 506, the CU receives a first DU-to-CU message from the DU in response to the first CU-to-DU message (e.g., event 312). In some implementations, the first DU-to-CU message confirms the successful configuration of the measurement gap. At block 508, the CU receives a second DU-to-CU message from the DU including gap configurations 1, ..., M after sending the first CU-to-DU message (e.g., event 314), where M is an integer and greater than zero. At block 510, the CU sends a second CU-to-DU message to the DU in response to the second DU-to-CU message (e.g., event 316). At block 512, the CU sends a message including gap configurations 1, ..., M to the UE via the DU (e.g., events 320, 322). At block 514, the CU sends a third CU-to-DU message to the DU to command the DU to activate at least one of gap configurations 1, ..., M (e.g., event 330). At block 516, the CU receives one or more measurement results from the UE via the DU (e.g., event 340).

[0118] In some implementations, the first CU to DU message includes TRP PRS information items 1, ..., N, where N is an integer and greater than zero. In some implementations, the first CU to DU message does not include measurement object information (e.g., MeasObjectToAddModList IE or MeasObjectToAddMod IE). In some implementations, the second DU to CU message includes a measurement gap configuration (e.g., MeasGapConfig IE), which includes gap configurations 1, ..., M (e.g., GapConfig IE or GapConfig-r17 IE 1, ..., M).

[0119] Figure 5B 5 is a flow chart of an example method 500B that is similar to method 500A, except that method 500B includes blocks 509 and 511 instead of blocks 508 and 510. At block 509, the CU sends a second CU-to-DU message to the DU after sending the first CU-to-DU message (e.g., event 315). At block 511, the CU receives a second DU-to-CU message including gap configurations 1, ..., M from the DU in response to the second CU-to-DU message (e.g., event 317).

[0120] Figure 5Cis a flow diagram of an example method 500C that is similar to method 500A, except that method 500C includes block 507 instead of blocks 506, 508, and 510. At block 507, the CU receives a first DU-to-CU message including gap configurations 1, ..., M of the UE from the DU in response to the first CU-to-DU message (e.g., event 313). In some implementations, the first DU-to-CU message confirms successful configuration of the measurement gap.

[0121] In previous figures (e.g., FIG. 3A to FIG. 4C The examples and implementations described in ) can be applied to FIG. 5A to FIG. 5C .

[0122] Next reference Figure 6 , method 600 is a method for configuring a measurement gap of a UE (eg, UE 102) and is implemented in a CU (eg, CU 172).

[0123] Method 600 begins at block 602, where the CU communicates with a UE (e.g., DU 174) via a DU. At block 604, the CU determines a measurement gap configured for the UE. At block 606, the CU determines whether the measurement gap is used for positioning measurement. If the measurement gap is used for positioning measurement, the process proceeds to block 608. At block 608, the CU sends a first CU-to-DU message to the DU in response to the determination (e.g., event 310). At block 610, the CU receives a first DU-to-CU message including a first measurement gap configuration (e.g., MeasGapConfig IE) from the DU (e.g., events 314, 317, 313). At block 612, the CU sends a first message including the first measurement gap configuration to the UE via the DU (e.g., events 320, 322). Otherwise, if the measurement gap is not used for positioning measurement, the process proceeds to block 614. At block 614, for the determination, the CU sends a second CU-to-DU message to the DU. At block 616, the CU receives a second DU-to-CU message including a second measurement gap configuration (eg, MeasGapConfig IE) from the DU. At block 618, the CU sends a second message including the second measurement gap configuration to the UE via the DU.

[0124] In some implementations, the first CU to DU message includes a TRP PRS information item, and the second CU to DU message does not include the TRP PRS information item. In some implementations, the second CU to DU message includes measurement object information (e.g., MeasObjectToAddModList IE or MeasObjectToAddMod IE), and the first CU to DU message does not include the measurement object information.

[0125] In some implementations, the second CU to DU message and the second DU to CU message are a UE context modification request message and a UE context modification response message. In some implementations, the second CU to DU message and the second DU to CU message are a UE context modification request message and a UE context modification required message. In such implementations, the CU receives a UE context modification response message from the DU in response to the UE context modification request message, and the CU sends a UE context modification confirmation message to the DU in response to the UE context modification required message.

[0126] In some implementations, the second message is an RRC reconfiguration message.In some such implementations, in response to the RRC reconfiguration message, the CU receives an RRC reconfiguration complete message from the UE via the DU.

[0127] In previous figures (e.g., FIG. 3A to FIG. 5C The examples and implementations described in ) can be applied to Figure 6 .

[0128] Next reference Fig. 7A , method 700A is a method for configuring a measurement gap of a UE (eg, UE 102) and is implemented in a CU (eg, CU 172).

[0129] Method 700A starts at block 702, where the flow performs at least one of methods 500A, 500B, or 500C. At block 704, the CU sends a first CU-to-DU message to the DU for releasing the gap configuration of the UE (e.g., event 345). At block 706, the CU receives a first DU-to-CU message from the DU in response to the first CU-to-DU message (e.g., event 347). At block 708, the CU receives a second DU-to-CU message from the DU including gap release information for releasing at least one of gap configurations 1, ..., M after sending the first CU-to-DU message (e.g., event 354). At block 710, the CU sends a second CU-to-DU message to the DU in response to the second DU-to-CU message (e.g., event 356). At block 712, the CU sends an RRC message including gap release information to the UE via the DU (e.g., events 321, 323). At block 714, the CU receives an RRC completion message from the UE via the DU (e.g., events 325, 327).

[0130] In some implementations, the gap release information includes a gap ID identifying at least one gap configuration. Each of the gap IDs identifies a specific one of the gap configurations. In some implementations, the DU identifies the released gap configuration based on the first CU to DU message. In some implementations, the first CU to DU message does not include measurement object information (e.g., MeasObjectToAddModList IE or MeasObjectToAddMod IE).

[0131] In some implementations, the CU receives a gap ID from the DU at block 702 (e.g., method 500A, 500B, or 500C). In some implementations, the CU includes the gap ID of at least one gap configuration in the first CU-to-DU message. Thus, the DU can identify at least one gap configuration based on the gap ID and release the at least one gap configuration accordingly. Alternatively, the CU does not include the gap ID in the first CU-to-DU message.

[0132] In some implementations, the CU sends a first TRP PRS information item to the DU at block 702. In some implementations, the CU includes zero TRP PRS information items in the first CU to DU message (i.e., the CU does not include the TRP PRS information item in the first CU to DU message). In some implementations, the CU includes zero TRP PRS information items to indicate or request the release of all gap configurations. When zero TRP PRS information items are received in the first CU to DU message, after receiving zero TRP PRS information items in the first CU to DU message, or in response to receiving zero TRP PRS information items in the first CU to DU message, the DU releases all gap configurations. In some implementations, when zero TRP PRS information items are received in the first CU to DU message, after receiving zero TRP PRS information items in the first CU to DU message, or in response to receiving zero TRP PRS information items in the first CU to DU message, the DU generates gap release information including gap IDs of all gap configurations.

[0133] In other implementations, the CU sends a first CU-to-DU message to the DU to indicate that positioning measurements are not required or configured. In such implementations, the DU releases all gap configurations upon, after, or in response to receiving the first CU-to-DU message. In some implementations, the DU generates gap release information including gap IDs of all gap configurations upon, after, or in response to receiving the first CU-to-DU message.

[0134] In other implementations, the CU includes the second TRPPRS message item in the first TRP PRS information item in the first CU to DU message. In some such implementations, the DU identifies the released gap configuration based on the second TRP PRS information item and the first TRP PRS information item. For example, the released gap configuration is associated with a TRPPRS information item that is not included in the second TRP PRS information item. In some implementations, the DU generates gap release information including a gap ID of the released gap configuration after identifying the released gap configuration.

[0135] In some implementations, the CU sends a first CU-to-DU message to the DU in response to receiving the LMF-to-BS message. For example, the LMF-to-BS message is Figure 3E or Figure 3F In other implementations, the CU sends the first CU-to-DU message to the DU in response to receiving the third DU-to-CU message from the DU. For example, the third DU-to-CU message is Figure 3D For another example, the third DU-to-CU message is a Positioning Measurement Failure Indication message.

[0136] Figure 7B is a flow chart of an example method 700B that is similar to the method 700A, except that the method 700B includes block 709 instead of blocks 708 and 710. At block 709, the CU generates gap release information for releasing at least one measurement gap configuration after sending the first CU-to-DU message.

[0137] In previous figures (e.g., Figures 3A to 6 The examples and implementations described in ) can be applied to Fig. 7A and Figure 7B .

[0138] Next reference Figure 8 , method 800 is a method for configuring a measurement gap of a UE (eg, UE 102) and is implemented in a DU (eg, DU 174).

[0139] Method 800 begins at block 802, where the process performs at least one of 400A, 400B, or 400C. At block 804, the DU receives a first CU-to-DU message from the DU for releasing the gap configuration of the UE (e.g., event 345). At block 806, the DU sends a first DU-to-CU message to the DU in response to the first CU-to-DU message (e.g., event 347). At block 808, the DU sends a second DU-to-CU message to the CU in response to the first CU-to-DU message (e.g., event 354) including gap release information for releasing at least one of gap configurations 1, ..., M. At block 810, the DU receives a second CU-to-DU message from the CU in response to the second DU-to-CU message (e.g., event 356). At block 812, the DU receives an RRC message from the CU including a gap release indication (e.g., event 321). At block 814, the DU sends an RRC message to the UE (e.g., event 323).

[0140] In previous figures (e.g., FIG. 3A to FIG. 7B The examples and implementations described in ) can be applied to Figure 8 .

[0141] The following description can be applied to the above description.

[0142] In general, the description of any one of the above figures may apply to another of the above figures. The above events or boxes may be optional or omitted. For example, an event or box with a dotted line in the figure may be optional or omitted. In some cases, an event or box with a solid line in the figure may still be optional, or may be omitted if the event or box is not required. In some implementations, "message" is used and "message" can be replaced with "information element (IE)", and vice versa. In some implementations, "IE" is used and "field" can be replaced with "IE", and vice versa. In some implementations, "configuration" can be replaced with "configurations" or "configuration parameters", and vice versa. In some implementations, "gap configuration" can be replaced with "preconfigured gap configuration".

[0143] The user device (e.g., UE 102) in which the technology of the present disclosure can be implemented can be any suitable device capable of wireless communication, such as a smart phone, a tablet computer, a laptop computer, a mobile game console, a point of sale (POS) terminal, a health monitoring device, a drone, a camera, a media streaming dongle or another personal media device, a wearable device such as a smart watch, a wireless hotspot, a femtocell or a broadband router. Further, in some cases, the user device can be embedded in an electronic system, such as a head unit or an advanced driver assistance system (ADAS) of a vehicle. Still further, the user device can be operated 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, a computer-readable memory, a user interface, one or more network interfaces, one or more sensors, etc.

[0144] Certain embodiments are described in the present disclosure as including logic or multiple components or modules. A module may be a software module (e.g., a code or machine-readable instruction stored on a non-temporary machine-readable medium) or a hardware module. A hardware module is a tangible unit that is capable of performing certain operations and may be configured or arranged in a particular manner. A hardware module may include a dedicated circuit system (circuitry) or logic that is permanently configured to perform certain operations (e.g., as a dedicated processor, such as a field programmable gate array (FPGA) or an application-specific integrated circuit (ASIC), a digital signal processor (DSP), etc.). A hardware module may also include programmable logic or circuit systems (e.g., as contained in a general-purpose processor or other programmable processor) that are temporarily configured by software to perform certain operations. The decision to implement a hardware module with a dedicated and permanently configured circuit system or with a temporarily configured circuit system (e.g., configured by software) may be driven by cost and time considerations.

[0145] When implemented in software, the techniques may be provided as part of an operating system, a library used by multiple applications, a specific software application, etc. The software may be executed by one or more general-purpose processors or one or more special-purpose processors.

Claims

1. A method for configuring reference signal measurements at a UE, the method being implemented in a central unit CU of a distributed base station further comprising a distributed unit DU, the method comprising: sending a first message including a request for configuring a measurement gap of the UE to the DU; receiving a second message including a measurement gap configuration from the DU; as well as The measurement gap configuration is provided to the UE for use with the reference signal measurement.

2. The method of claim 1, wherein: The measurement gap configuration includes: A preconfiguration indicator is used to indicate that the gap configuration is preconfigured.

3. The method according to claim 1 or 2, wherein: The measurement gap configuration includes: MeasGapConfig information element IE.

4. A method as claimed in any one of the preceding claims, wherein: The first message comprises a measurement-required pre-configuration message.

5. A method as claimed in any one of the preceding claims, wherein: The first message includes a measurement pre-configuration confirmation message.

6. The method according to any one of the preceding claims, further comprising: A measurement pre-configuration required message is received from a location management function LMF and before said sending said first message.

7. The method of claim 6, wherein: The measurement pre-configuration message includes the transmission reception point TRP positioning reference signal PRS information; and Sending the first message to the DU includes sending the TRP PRS information to the DU.

8. The method of any preceding claim, further comprising, after providing the measurement gap configuration to the UE: A request for activating the measurement gap configuration is sent to the DU.

9. The method of claim 8, wherein: The request includes positioning reference signal (PRS) measurement information.

10. The method according to claim 8 or 9, wherein: The request for activating the measurement gap configuration is a measurement activation message.

11. A method as claimed in any one of the preceding claims, wherein: Sending the first message includes sending one of a CU to DU message or an F1 Application Protocol F1AP message.

12. A method for configuring reference signal measurements at a UE, the method being implemented in a distributed unit DU of a distributed base station further comprising a central unit CU, the method comprising: receiving, from the CU, a first message including a request for configuring a measurement gap of the UE; as well as A second message including a measurement gap configuration is sent to the CU.

13. The method of claim 12, wherein: The request for configuring the measurement gap includes transmitting a reception point TRP positioning reference signal PRS information; the method further includes: The measurement gap configuration is generated using the TRP PRS information.

14. The method of claim 12 or 13, wherein: The measurement gap configuration includes a gap identifier ID.

15. A Radio Access Network, RAN, node comprising processing hardware and configured to implement the method according to any one of the preceding claims.

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