Communication terminal, base transceiver station, and communication system

Abstract

To provide an excellent communication service by achieving latency reduction in positioning.SOLUTION: A communication system includes a communication terminal, a base-station apparatus including a TRP (TransmissionReceptionPoint) that performs radio communication with the communication terminal, and an LMF node, and a communication terminal UE receives information on a location of the TRP from the LMF node. The information about the location of the TRP includes information about accuracy of the location of the TRP.SELECTED DRAWING: Figure 28

Description

[Technical Field]

[0001] The present disclosure relates to wireless communication technology. [Background technology]

[0002] 3GPP (3rd Generation Partnership Project), a standardization organization for mobile communication systems, is considering a communication method called Long Term Evolution (LTE) for the wireless section and System Architecture Evolution (SAE) for the overall system configuration including the core network and radio access network (hereinafter collectively referred to as the network) (see, for example, Non-Patent Documents 1 to 5). This communication method is also called the 3.9G (3.9 Generation) system.

[0003] LTE uses OFDM (Orthogonal Frequency Division Multiplexing) for downlink and SC-FDMA (Single Carrier Frequency Division Multiple Access) for uplink as its access method. Unlike W-CDMA (Wideband Code Division Multiple Access), LTE does not include circuit switching and is only a packet communication method.

[0004] The decisions made by 3GPP regarding the frame configuration in the LTE system, as described in Non-Patent Document 1 (Chapter 5), will be explained using Figure 1. Figure 1 is an explanatory diagram showing the configuration of a radio frame used in an LTE communication system. In Figure 1, one radio frame is 10 ms. The radio frame is divided into 10 equally sized subframes. The subframe is divided into two equally sized slots. The first and sixth subframes of each radio frame include a downlink synchronization signal. The synchronization signals include a primary synchronization signal (P-SS) and a secondary synchronization signal (S-SS).

[0005] The decisions made by 3GPP regarding the channel configuration in the LTE system are described in Non-Patent Document 1 (Chapter 5). It is assumed that the same channel configuration as that of a non-CSG cell is used in a CSG (Closed Subscriber Group) cell.

[0006] The Physical Broadcast Channel (PBCH) is a channel for downlink transmission from a base station (hereinafter simply referred to as a "base station") to a communication terminal (hereinafter simply referred to as a "communication terminal") such as a mobile terminal (hereinafter simply referred to as a "mobile terminal"). A BCH transport block is mapped to four subframes in a 40 ms interval. There is no explicit signaling of the 40 ms timing.

[0007] The Physical Control Format Indicator Channel (PCFICH) is a channel for downlink transmission from a base station to a communication terminal. The PCFICH notifies the communication terminal of the number of Orthogonal Frequency Division Multiplexing (OFDM) symbols used for PDCCHs. The PCFICH is transmitted every subframe.

[0008] The Physical Downlink Control Channel (PDCCH) is a channel for downlink transmission from a base station to a communication terminal. The PDCCH reports resource allocation information for a Downlink Shared Channel (DL-SCH), which is one of the transport channels described below, resource allocation information for a Paging Channel (PCH), which is also one of the transport channels described below, and Hybrid Automatic Repeat reQuest (HARQ) information for the DL-SCH. The PDCCH carries an uplink scheduling grant. The PDCCH carries Acknowledgement (Ack) / Negative Acknowledgement (Nack), which are response signals to uplink transmissions. The PDCCH is also called an L1 / L2 control signal.

[0009] The Physical Downlink Shared Channel (PDSCH) is a channel for downlink transmission from a base station to a communication terminal. A Downlink Shared Channel (DL-SCH), which is a transport channel, and a PCH, which is also a transport channel, are mapped to the PDSCH.

[0010] A physical multicast channel (PMCH) is a channel for downlink transmission from a base station to communication terminals, and a multicast channel (MCH), which is a transport channel, is mapped to the PMCH.

[0011] The Physical Uplink Control Channel (PUCCH) is a channel for uplink transmission from a communication terminal to a base station. The PUCCH carries Ack / Nack, which are response signals to downlink transmissions. The PUCCH carries Channel State Information (CSI). The CSI consists of a Rank Indicator (RI), a Precoding Matrix Indicator (PMI), and a Channel Quality Indicator (CQI) report. The RI is information on the rank of the channel matrix in MIMO. The PMI is information on the precoding weight matrix used in MIMO. The CQI is quality information that indicates the quality of received data or the quality of the communication path. The PUCCH also carries a Scheduling Request (SR).

[0012] The Physical Uplink Shared Channel (PUSCH) is a channel for uplink transmission from a communication terminal to a base station. The Uplink Shared Channel (UL-SCH), which is one of the transport channels, is mapped to the PUSCH.

[0013] The Physical Hybrid ARQ Indicator Channel (PHICH) is a channel for downlink transmission from a base station to a communication terminal. The PHICH carries Ack / Nack, which are response signals to uplink transmission. The Physical Random Access Channel (PRACH) is a channel for uplink transmission from a communication terminal to a base station. The PRACH carries a random access preamble.

[0014] Downlink reference signals (RS) are symbols known in LTE communication systems. The following five types of downlink reference signals are defined: Cell-specific Reference Signal (CRS), MBSFN Reference Signal, UE-specific reference signal Demodulation Reference Signal (DM-RS), Positioning Reference Signal (PRS), and Channel State Information Reference Signal (CSI-RS). Measurement of the physical layer of a communication terminal includes measurement of the reference signal received power (RSRP).

[0015] Similarly, the uplink reference signal is a symbol known in LTE communication systems. Two types of uplink reference signals are defined: a data demodulation reference signal (DM-RS) and a sounding reference signal (SRS).

[0016] The transport channels described in Non-Patent Document 1 (Chapter 5) will be explained below. Among the downlink transport channels, a broadcast channel (BCH) is broadcast to the entire coverage of the base station (cell). The BCH is mapped to a physical broadcast channel (PBCH).

[0017] Retransmission control using HARQ (Hybrid ARQ) is applied to the Downlink Shared Channel (DL-SCH). DL-SCH can be broadcast to the entire coverage of a base station (cell). DL-SCH supports dynamic or semi-static resource allocation. Semi-static resource allocation is also called persistent scheduling. DL-SCH supports discontinuous reception (DRX) in communication terminals to reduce power consumption of communication terminals. DL-SCH is mapped to the Physical Downlink Shared Channel (PDSCH).

[0018] The Paging Channel (PCH) supports DRX in communication terminals to enable low power consumption in communication terminals. The PCH is required to broadcast to the entire coverage of the base station (cell). The PCH is mapped to physical resources such as the Physical Downlink Shared Channel (PDSCH) that can be dynamically used for traffic.

[0019] The Multicast Channel (MCH) is used for broadcasting to the entire coverage of a base station (cell). The MCH supports SFN combining of MBMS (Multimedia Broadcast Multicast Service) services (MTCH and MCCH) in multi-cell transmission. The MCH supports semi-static resource allocation. The MCH is mapped to the PMCH.

[0020] Among the uplink transport channels, the Uplink Shared Channel (UL-SCH) is subject to retransmission control using HARQ (Hybrid ARQ). The UL-SCH supports dynamic or semi-static resource allocation. The UL-SCH is mapped to the Physical Uplink Shared Channel (PUSCH).

[0021] The Random Access Channel (RACH) is limited to control information. The RACH is subject to collision risk. The RACH is mapped to the Physical Random Access Channel (PRACH).

[0022] We will explain HARQ. HARQ is a technology that improves the communication quality of a transmission channel by combining Automatic Repeat reQuest (ARQ) and Forward Error Correction. HARQ has the advantage that error correction works effectively through retransmission even on transmission channels where communication quality varies. In particular, by combining the reception results of the initial transmission and the retransmission when retransmitting, it is possible to achieve further quality improvement.

[0023] An example of a retransmission method will be explained below. If the receiving side is unable to decode the received data correctly, in other words, if a CRC (Cyclic Redundancy Check) error occurs (CRC=NG), the receiving side will send a "Nack" to the sending side. The sending side, having received the "Nack," will retransmit the data. If the receiving side is able to decode the received data correctly, in other words, if no CRC error occurs (CRC=OK), the receiving side will send an "Ack" to the sending side. The sending side, having received the "Ack," will send the next data.

[0024] The logical channels described in Non-Patent Document 1 (Chapter 6) will be explained below. The Broadcast Control Channel (BCCH) is a downlink channel for broadcast system control information. The BCCH, which is a logical channel, is mapped to the broadcast channel (BCH) or the downlink shared channel (DL-SCH), which are transport channels.

[0025] The Paging Control Channel (PCCH) is a downlink channel for transmitting paging information and changes to system information. The PCCH is used when the network does not know the cell location of the communication terminal. The PCCH, which is a logical channel, is mapped to the Paging Channel (PCH), which is a transport channel.

[0026] A Common Control Channel (CCCH) is a channel for transmission control information between a communication terminal and a base station. CCCH is used when a communication terminal does not have an RRC connection with the network. In the downlink direction, CCCH is mapped to a Downlink Shared Channel (DL-SCH), which is a transport channel. In the uplink direction, CCCH is mapped to an Uplink Shared Channel (UL-SCH), which is a transport channel.

[0027] The Multicast Control Channel (MCCH) is a downlink channel for point-to-multipoint transmission. The MCCH is used to transmit MBMS control information for one or several MTCHs from the network to communication terminals. The MCCH is used only by communication terminals receiving MBMS. The MCCH is mapped to the Multicast Channel (MCH), which is a transport channel.

[0028] A dedicated control channel (DCCH) is a channel that transmits dedicated control information between a communication terminal and a network on a one-to-one basis. The DCCH is used when the communication terminal is in an RRC connection. The DCCH is mapped to an uplink shared channel (UL-SCH) in the uplink and to a downlink shared channel (DL-SCH) in the downlink.

[0029] A Dedicated Traffic Channel (DTCH) is a one-to-one communication channel for transmitting user information to an individual communication terminal. DTCH exists in both uplink and downlink. In uplink, DTCH is mapped to an uplink shared channel (UL-SCH) and in downlink, it is mapped to a downlink shared channel (DL-SCH).

[0030] The Multicast Traffic Channel (MTCH) is a downlink channel for transmitting traffic data from the network to communication terminals. The MTCH is a channel used only by communication terminals receiving MBMS. The MTCH is mapped to the Multicast Channel (MCH).

[0031] CGI stands for Cell Global Identifier. ECGI stands for E-UTRAN Cell Global Identifier. Closed Subscriber Group (CSG) cells are introduced in LTE, LTE-A (Long Term Evolution Advanced) (described below), and UMTS (Universal Mobile Telecommunication System).

[0032] The location of a communication terminal is tracked in units of an area consisting of one or more cells. Location tracking is performed to track the location of the communication terminal even when it is in standby mode and to enable the communication terminal to be called, in other words, to allow the communication terminal to receive calls. The area used for tracking the location of this communication terminal is called a tracking area.

[0033] 3GPP is also working on the development of the Long Term Evolution Advanced (LTE-A) standard as Release 10 (see Non-Patent Documents 3 and 4). LTE-A is based on the LTE wireless communication system, and is configured by adding several new technologies to it.

[0034] In the LTE-A system, carrier aggregation (CA) is being considered, which aggregates two or more component carriers (CCs) (also called "aggregation") to support wider frequency bandwidths (transmission bandwidths) up to 100 MHz. CA is described in Non-Patent Document 1.

[0035] When CA is configured, the UE has only one RRC connection with the network (NW). In the RRC connection, one serving cell provides NAS mobility information and security input. This cell is called the primary cell (PCell). In the downlink, the carrier corresponding to the PCell is the downlink primary component carrier (DL PCC). In the uplink, the carrier corresponding to the PCell is the uplink primary component carrier (UL PCC).

[0036] Depending on the UE's capabilities, a secondary cell (SCell) is configured to form a serving cell set together with the PCell. In the downlink, the carrier corresponding to the SCell is the downlink secondary component carrier (DL SCC). In the uplink, the carrier corresponding to the SCell is the uplink secondary component carrier (UL SCC).

[0037] A set of serving cells, which includes one PCell and one or more SCells, is configured for one UE.

[0038] Furthermore, new technologies for LTE-A include wider bandwidth extension and Coordinated Multiple Point transmission and reception (CoMP) technology. CoMP, which is being considered for LTE-A by 3GPP, is described in Non-Patent Document 1.

[0039] Furthermore, in order to handle future massive traffic volumes, 3GPP is considering using small eNBs (hereinafter sometimes referred to as "small-scale base station devices") that configure small cells. For example, technologies are being considered that aim to increase communication capacity by installing a large number of small eNBs and configuring a large number of small cells to improve frequency utilization efficiency. Specifically, there is dual connectivity (abbreviated as DC), in which a UE connects to two eNBs to communicate. DC is described in Non-Patent Document 1.

[0040] Of the eNBs that perform dual connectivity (DC), one may be referred to as a "master eNB (abbreviated as MeNB)" and the other as a "secondary eNB (abbreviated as SeNB)."

[0041] Mobile network traffic volume is on the rise, and communication speeds are also increasing. Once LTE and LTE-A are fully operational, communication speeds are expected to increase even further.

[0042] Furthermore, in response to the increasing sophistication of mobile communications, fifth-generation (hereinafter sometimes referred to as "5G") wireless access systems are being considered, with the goal of launching services after 2020. For example, in Europe, an organization called METIS has compiled requirements for 5G (see Non-Patent Document 5).

[0043] The requirements for a 5G wireless access system are that it will have 1,000 times the system capacity, 100 times the data transmission speed, one-tenth (1 / 10) the data processing delay, and 100 times the number of simultaneous connections of communication terminals compared to an LTE system, while also achieving further reductions in power consumption and lower equipment costs.

[0044] To meet these demands, 3GPP is currently working on 5G standards as Release 15 (see Non-Patent Documents 6 to 18). 5G wireless access technology is called "New Radio Access Technology" ("New Radio" is abbreviated as "NR").

[0045] The NR system is being developed based on the LTE system and LTE-A system, but the following changes and additions have been made to the LTE system and LTE-A system.

[0046] The NR access method uses OFDM in the downlink direction and OFDM and DFT-s-OFDM (DFT-spread-OFDM) in the uplink direction.

[0047] NR allows the use of higher frequencies than LTE in order to improve transmission speeds and reduce processing delays.

[0048] In NR, cell coverage is ensured by forming a narrow beam-shaped transmission and reception range (beamforming) and changing the direction of the beam (beam sweeping).

[0049] The NR frame structure supports various subcarrier spacings, i.e., various numerologies. In NR, regardless of the numerology, one subframe is 1 millisecond and one slot consists of 14 symbols. The number of slots included in one subframe is one in a numerology with a subcarrier spacing of 15 kHz, but increases in proportion to the subcarrier spacing in other numerologies (see Non-Patent Document 13 (TS38.211 V16.2.0)).

[0050] In NR, downlink synchronization signals are transmitted from base stations as synchronization signal bursts (hereinafter sometimes referred to as SS bursts) at predetermined intervals for a predetermined duration. SS bursts consist of synchronization signal blocks (hereinafter sometimes referred to as SS blocks) for each beam of the base station. The base station transmits the SS blocks of each beam within the duration of the SS burst, changing the beam. SS blocks consist of P-SS, S-SS, and PBCH.

[0051] In NR, the influence of phase noise is reduced by adding a Phase Tracking Reference Signal (PTRS) as a downlink reference signal for NR. PTRS is also added to the uplink reference signal, just like in the downlink.

[0052] In NR, slot format indication (SFI) has been added to the information contained in the PDCCH in order to flexibly switch between DL and UL within a slot.

[0053] In addition, in NR, the base station pre-configures a portion of the carrier frequency band (hereinafter sometimes referred to as the Bandwidth Part (BWP)) for the UE, and the UE transmits and receives data to and from the base station using this BWP, thereby reducing power consumption in the UE.

[0054] 3GPP is considering the following DC forms: DC by LTE base stations and NR base stations connected to EPC, DC by NR base stations connected to a 5G core system, and DC by LTE base stations and NR base stations connected to a 5G core system (see Non-Patent Documents 12, 16, and 19).

[0055] Additionally, 3GPP is studying several new technologies, such as positioning technologies (see Non-Patent Documents 22 to 25 and 28). As a positioning technology, for example, a positioning method (Multi-Round Trip Time; Multi-RTT) that uses round-trip delay times between a UE and multiple base stations is being studied (see Non-Patent Document 25). [Prior art documents] [Non-patent literature]

[0056] [Non-Patent Document 1] 3GPP TS 36.300 V16.2.0 [Non-patent document 2] 3GPP S1-083461 [Non-patent document 3] 3GPP TR 36.814 V9.2.0 [Non-patent document 4] 3GPP TR 36.912 V16.0.0 [Non-patent document 5] "Scenarios, requirements and KPIs for 5G mobile and wireless system", ICT-317669-METIS / D1.1

Non-licensed Document 6

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Non-licensed literature 9

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Non-licensed Document 11

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Non-licensed Document 15

Non-licensed Document 16

Non-licensed Document 17

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Non-licensed Document 21

[0057] In Multi-RTT, a UE needs to transmit and receive positioning signals to and from multiple base stations. In order to transmit and receive positioning signals to and from neighboring base stations other than the serving base station, the UE requests the serving base station to change the measurement gap setting (a period during which transmission and reception with the serving base station is suspended and measurements are made with other base stations). The base station sets a measurement gap for the UE based on the measurement gap request. However, since the measurement gap request from the UE is made after positioning has started, it takes longer to perform UE positioning, resulting in increased latency in positioning.

[0058] In view of the above-mentioned problems, one of the objects of the present disclosure is to provide a good communication service by realizing a reduction in latency in positioning. [Means for solving the problem]

[0059] The communication system according to the present disclosure is a communication system comprising a communication terminal and a serving base station for the communication terminal, wherein the serving base station notifies the communication terminal, without a request from the communication terminal, of an instruction to set a measurement gap for the communication terminal to measure a positioning signal transmitted from at least one surrounding base station in order to measure the position of the communication terminal. The base station according to the present disclosure is a base station that operates as a serving base station for a communication terminal, and is characterized in that the base station notifies the communication terminal, without a request from the communication terminal, of an instruction to set a measurement gap for the communication terminal to measure a positioning signal transmitted from at least one surrounding base station in order to measure the position of the communication terminal. [Effects of the Invention]

[0060] According to the present disclosure, good communication can be provided.

[0061] The objects, features, aspects, and advantages of the present disclosure will become more apparent from the following detailed description and the accompanying drawings. [Brief explanation of the drawings]

[0062] [Figure 1] FIG. 1 is an explanatory diagram showing the configuration of a radio frame used in an LTE communication system. [Figure 2] 1 is a block diagram showing the overall configuration of an LTE communication system 200 being discussed in 3GPP. [Figure 3] FIG. 2 is a block diagram showing the overall configuration of a communication system 210 conforming to the NR standard under discussion in 3GPP. [Figure 4] This is a diagram illustrating the configuration of DC using eNB and gNB connected to EPC. [Figure 5] This is a diagram of the DC configuration using gNB connected to the NG core. [Figure 6] This is a diagram illustrating the configuration of DC using eNB and gNB connected to the NG core. [Figure 7]This is a diagram illustrating the configuration of DC using eNB and gNB connected to the NG core. [Figure 8] FIG. 3 is a block diagram showing the configuration of a mobile terminal 202 shown in FIG. [Figure 9] FIG. 3 is a block diagram showing the configuration of a base station 203 shown in FIG. [Figure 10] FIG. 2 is a block diagram illustrating the configuration of an MME. [Figure 11] A block diagram showing the configuration of 5GC. [Figure 12] 1 is a flowchart showing an outline of operations from cell search to standby operation performed by a communication terminal (UE) in an LTE communication system. [Figure 13] FIG. 1 is a diagram illustrating an example of a cell configuration in an NR system. [Figure 14] FIG. 10 is a sequence diagram showing a first example of a positioning operation in the case where a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE, according to the first embodiment. [Figure 15] FIG. 10 is a sequence diagram showing a first example of a positioning operation in the case where a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE, according to the first embodiment. [Figure 16] FIG. 10 is a sequence diagram showing a second example of the positioning operation in the case where a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE, in accordance with the first embodiment. [Figure 17] FIG. 10 is a sequence diagram showing a second example of the positioning operation in the case where a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE, in accordance with the first embodiment. [Figure 18] FIG. 10 is a sequence diagram showing the operation of Multi-RTT when the serving base station has an LMF, according to the first embodiment. [Figure 19]FIG. 10 is a sequence diagram showing the operation of Multi-RTT when the serving base station has an LMF, according to the first embodiment. [Figure 20] FIG. 10 is a sequence diagram showing a positioning method in which a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE when the serving base station has an LMF, according to the first embodiment. [Figure 21] FIG. 10 is a sequence diagram showing a positioning method in which a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE when the serving base station has an LMF, according to the first embodiment. [Figure 22] FIG. 10 is a sequence diagram showing the operation of Multi-RTT when the UE has an LMF, according to the first embodiment. [Figure 23] FIG. 10 is a sequence diagram showing the operation of Multi-RTT when the UE has an LMF, according to the first embodiment. [Figure 24] FIG. 10 is a sequence diagram showing a positioning method in which a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE, in a case where the UE has an LMF, according to the first embodiment. [Figure 25] FIG. 10 is a sequence diagram showing a positioning method in which a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE, in a case where the UE has an LMF, according to the first embodiment. [Figure 26] FIG. 10 is a diagram showing an operation of a neighboring base station performing beam sweeping within the range of a beam used by a serving base station for communication with a UE, according to a first modification of the first embodiment. [Figure 27] FIG. 10 is a diagram illustrating an example in which a serving base station notifies, as information on a serving beam, an area that overlaps with the range of the serving beam among a plurality of predetermined areas, in accordance with a first modification of the first embodiment. [Figure 28]FIG. 11 is a sequence diagram showing an operation performed by a UE to calculate its own location in Multi-RTT according to the second embodiment. [Figure 29] FIG. 11 is a sequence diagram showing an operation performed by a UE to calculate its own location in Multi-RTT according to the second embodiment. [Figure 30] FIG. 11 is a sequence diagram showing an operation performed by a UE to calculate its position in Multi-RTT in a case where a base station has an LMF, according to the second embodiment. [Figure 31] FIG. 11 is a sequence diagram showing an operation performed by a UE to calculate its position in Multi-RTT in a case where a base station has an LMF, according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0063] Embodiment 1 Fig. 2 is a block diagram showing the overall configuration of an LTE communication system 200 being discussed in 3GPP. Fig. 2 will now be described. The radio access network is called E-UTRAN (Evolved Universal Terrestrial Radio Access Network) 201. A mobile terminal device (hereinafter referred to as "mobile terminal (User Equipment: UE)") 202, which is a communication terminal device, is capable of wireless communication with a base station device (hereinafter referred to as "base station (E-UTRAN NodeB: eNB)") 203, and transmits and receives signals via wireless communication.

[0064] Here, the term "communication terminal device" includes not only mobile terminal devices such as mobile cell phone terminal devices, but also stationary devices such as sensors. In the following description, the term "communication terminal device" may be simply referred to as a "communication terminal."

[0065] If control protocols for mobile terminals 202, such as RRC (Radio Resource Control), and user planes (hereinafter sometimes referred to as U-Planes), such as PDCP (Packet Data Convergence Protocol), RLC (Radio Link Control), MAC (Medium Access Control), and PHY (Physical layer), terminate at base stations 203, E-UTRAN is composed of one or more base stations 203.

[0066] The control protocol RRC (Radio Resource Control) between the mobile terminal 202 and the base station 203 performs broadcasting, paging, RRC connection management, etc. The states of the base station 203 and the mobile terminal 202 in RRC include RRC_IDLE and RRC_CONNECTED.

[0067] In RRC_IDLE, PLMN (Public Land Mobile Network) selection, system information (SI) broadcast, paging, cell reselection, mobility, etc. are performed. In RRC_CONNECTED, the mobile terminal has an RRC connection and can transmit and receive data with the network. In addition, in RRC_CONNECTED, handover (HO), measurement of neighbor cells, etc. are performed.

[0068] The base station 203 is configured by one or more eNBs 207. A system configured by the core network EPC (Evolved Packet Core) and the radio access network E-UTRAN 201 is called an EPS (Evolved Packet System). The core network EPC and the radio access network E-UTRAN 201 are sometimes collectively referred to as a "network."

[0069] The eNB 207 is connected to a Mobility Management Entity (MME), or a Serving Gateway (S-GW), or an MME / S-GW unit (hereinafter sometimes referred to as an "MME unit") 204 including an MME and an S-GW via an S1 interface, and control information is communicated between the eNB 207 and the MME unit 204. Multiple MME units 204 may be connected to one eNB 207. The eNBs 207 are connected to each other via an X2 interface, and control information is communicated between the eNBs 207.

[0070] The MME unit 204 is an upper device, specifically an upper node, and controls the connection between the eNB 207, which is a base station, and the mobile terminal (UE) 202. The MME unit 204 constitutes the EPC, which is a core network. The base station 203 constitutes the E-UTRAN 201.

[0071] Base station 203 may configure one cell or multiple cells. Each cell has a predetermined range as coverage, which is the range within which communication with mobile terminal 202 is possible, and performs wireless communication with mobile terminal 202 within the coverage. When one base station 203 configures multiple cells, each cell is configured to be able to communicate with mobile terminal 202.

[0072] Figure 3 is a block diagram showing the overall configuration of a 5G communication system 210 being discussed in 3GPP. The following describes Figure 3. The radio access network is referred to as a Next Generation Radio Access Network (NG-RAN) 211. The UE 202 is capable of wireless communication with an NR base station device (hereinafter referred to as an "NR base station (NG-RAN NodeB: gNB)") 213, and transmits and receives signals via wireless communication. The core network is referred to as a 5G Core (5GC).

[0073] If control protocols for UE202, such as RRC (Radio Resource Control), and user plane (hereinafter sometimes referred to as U-Plane), such as SDAP (Service Data Adaptation Protocol), PDCP (Packet Data Convergence Protocol), RLC (Radio Link Control), MAC (Medium Access Control), and PHY (Physical layer), terminate at the NR base station 213, the NG-RAN is composed of one or more NR base stations 213.

[0074] The function of the control protocol RRC (Radio Resource Control) between the UE 202 and the NR base station 213 is the same as that of LTE. The states of the NR base station 213 and the UE 202 in the RRC include RRC_IDLE, RRC_CONNECTED, and RRC_INACTIVE.

[0075] RRC_IDLE and RRC_CONNECTED are the same as those in the LTE system. RRC_INACTIVE maintains the connection between the 5G core and the NR base station 213, and performs system information (SI), paging, cell reselection, mobility, and the like.

[0076] The gNB 217 is connected to an AMF / SMF / UPF unit (hereinafter sometimes referred to as the "5GC unit") 214, which includes an Access and Mobility Management Function (AMF), a Session Management Function (SMF), or a User Plane Function (UPF), or an AMF, SMF, and UPF, via an NG interface. Control information and / or user data are communicated between the gNB 217 and the 5GC unit 214. The NG interface is a collective term for the N2 interface between the gNB 217 and the AMF, the N3 interface between the gNB 217 and the UPF, the N11 interface between the AMF and the SMF, and the N4 interface between the UPF and the SMF. Multiple 5GC units 214 may be connected to one gNB 217. The gNBs 217 are connected to each other via an Xn interface, and control information and / or user data are communicated between the gNBs 217.

[0077] The NR base station 213 may configure one or more cells, similar to the base station 203. When one NR base station 213 configures multiple cells, each cell is configured to be able to communicate with the UE 202.

[0078] The gNB 217 may be divided into a central unit (hereinafter, sometimes referred to as a CU) 218 ​​and distributed units (hereinafter, sometimes referred to as DUs) 219. One CU 218 is configured in the gNB 217. One or more DUs 219 are configured in the gNB 217. The CU 218 is connected to the DU 219 via an F1 interface, and control information and / or user data is communicated between the CU 218 and the DU 219.

[0079] A 5G communication system may include a Unified Data Management (UDM) function and a Policy Control Function (PCF) described in Non-Patent Document 20 (3GPP TS23.501 V16.5.0). The UDM and / or PCF may be included in the 5GC unit in FIG. 3.

[0080] In a 5G communication system, a location management function (LMF) described in Non-Patent Document 22 (3GPP TS38.305 V16.0.0) may be provided.

[0081] A 5G communication system may include a Non-3GPP Interworking Function (N3IWF) described in Non-Patent Document 20 (3GPP TS23.501 V16.5.0). The N3IWF may terminate an Access Network (AN) between the UE and the N3IWF in non-3GPP access between the UE and the N3IWF.

[0082] Fig. 4 is a diagram showing a DC configuration by eNBs and gNBs connected to EPC. In Fig. 4, solid lines indicate U-Plane connections, and dashed lines indicate C-Plane connections. In Fig. 4, eNB223-1 serves as the master base station, and gNB224-2 serves as the secondary base station (this DC configuration may be referred to as EN-DC). Fig. 4 shows an example in which U-Plane connection between MME unit 204 and gNB224-2 is made via eNB223-1, but it may also be made directly between MME unit 204 and gNB224-2.

[0083] Figure 5 is a diagram showing the configuration of DC by a gNB connected to an NG core. In Figure 5, solid lines indicate U-Plane connections, and dashed lines indicate C-Plane connections. In Figure 5, gNB 224-1 is the master base station, and gNB 224-2 is the secondary base station (this DC configuration may be referred to as NR-DC). Figure 5 shows an example in which U-Plane connection between 5GC unit 214 and gNB 224-2 is made via gNB 224-1, but it may also be made directly between 5GC unit 214 and gNB 224-2.

[0084] Figure 6 is a diagram showing a DC configuration by eNB and gNB connected to the NG core. In Figure 6, solid lines indicate U-Plane connections, and dashed lines indicate C-Plane connections. In Figure 6, eNB226-1 is the master base station, and gNB224-2 is the secondary base station (this DC configuration may be referred to as NG-EN-DC). Figure 6 shows an example in which U-Plane connection between 5GC unit 214 and gNB224-2 is made via eNB226-1, but it may also be made directly between 5GC unit 214 and gNB224-2.

[0085] Figure 7 is a diagram showing another configuration of DC by eNB and gNB connected to the NG core. In Figure 7, solid lines indicate U-Plane connections, and dashed lines indicate C-Plane connections. In Figure 7, gNB224-1 is the master base station, and eNB226-2 is the secondary base station (this DC configuration may be referred to as NE-DC). Figure 7 shows an example in which U-Plane connection between 5GC unit 214 and eNB226-2 is made via gNB224-1, but it may also be made directly between 5GC unit 214 and eNB226-2.

[0086] FIG. 8 is a block diagram showing the configuration of mobile terminal 202 shown in FIG. 2. The transmission process of mobile terminal 202 shown in FIG. 8 will be described. First, control data from protocol processing unit 301 and user data from application unit 302 are stored in transmission data buffer unit 303. The data stored in transmission data buffer unit 303 is passed to encoder unit 304, where it is subjected to encoding processes such as error correction. Some data may be output directly from transmission data buffer unit 303 to modulation unit 305 without being encoded. The data encoded by encoder unit 304 is modulated by modulation unit 305. Precoding in MIMO may be performed by modulation unit 305. The modulated data is converted into a baseband signal, and then output to frequency conversion unit 306, where it is converted into a radio transmission frequency. Thereafter, a transmission signal is transmitted to base station 203 from antennas 307-1 to 307-4. Although FIG. 8 illustrates an example in which the number of antennas is four, the number of antennas is not limited to four.

[0087] Furthermore, the reception process of mobile terminal 202 is performed as follows. Radio signals from base station 203 are received by antennas 307-1 to 307-4. The received signals are converted from a radio reception frequency to a baseband signal by frequency conversion unit 306, and demodulated by demodulation unit 308. Demodulation unit 308 may also perform weight calculation and multiplication processing. The demodulated data is passed to decoder unit 309, where decoding processing such as error correction is performed. Of the decoded data, control data is passed to protocol processing unit 301, and user data is passed to application unit 302. A series of processes of mobile terminal 202 is controlled by control unit 310. Therefore, although control unit 310 is omitted in FIG. 8, it is connected to each unit 301 to 309. In FIG. 8, the number of antennas used by mobile terminal 202 for transmission and the number of antennas used for reception may be the same or different.

[0088] 2. The transmission process of the base station 203 shown in FIG. 9 will be described. The EPC communication unit 401 transmits and receives data between the base station 203 and the EPC (such as the MME unit 204). The 5GC communication unit 412 transmits and receives data between the base station 203 and the 5GC (such as the 5GC unit 214). The other base station communication unit 402 transmits and receives data with other base stations. The EPC communication unit 401, the 5GC communication unit 412, and the other base station communication unit 402 each exchange information with the protocol processing unit 403. The control data from the protocol processing unit 403, and the user data and control data from the EPC communication unit 401, the 5GC communication unit 412, and the other base station communication unit 402 are stored in the transmission data buffer unit 404.

[0089] The data stored in transmission data buffer unit 404 is passed to encoder unit 405, where it undergoes encoding processing such as error correction. Some data may be output directly from transmission data buffer unit 404 to modulation unit 406 without undergoing encoding processing. The encoded data is modulated by modulation unit 406. MIMO precoding may be performed by modulation unit 406. The modulated data is converted into a baseband signal, and then output to frequency conversion unit 407, where it is converted into a radio transmission frequency. Thereafter, a transmission signal is transmitted to one or more mobile terminals 202 from antennas 408-1 to 408-4. Although FIG. 9 illustrates an example in which the number of antennas is four, the number of antennas is not limited to four.

[0090] The reception process of the base station 203 is performed as follows: A radio signal from one or more mobile terminals 202 is received by an antenna 408. The received signal is converted from a radio reception frequency to a baseband signal by a frequency conversion unit 407, and demodulated by a demodulation unit 409. The demodulated data is passed to a decoder unit 410, where decoding processes such as error correction are performed. Of the decoded data, control data is passed to the protocol processing unit 403, the 5GC communication unit 412, the EPC communication unit 401, or the other base station communication unit 402, and user data is passed to the 5GC communication unit 412, the EPC communication unit 401, and the other base station communication unit 402. A series of processes of the base station 203 is controlled by a control unit 411. Therefore, although the control unit 411 is omitted in FIG. 9, it is connected to each unit 401 to 410. In FIG. 9, the number of antennas used for transmission by the base station 203 and the number of antennas used for reception may be the same or different.

[0091] 9 is a block diagram showing the configuration of base station 203, but base station 213 may have a similar configuration. In addition, in FIGS. 8 and 9, the number of antennas of mobile terminal 202 and the number of antennas of base station 203 may be the same or different.

[0092] 10 is a block diagram showing the configuration of an MME. FIG. 10 shows the configuration of an MME 204a included in the MME unit 204 shown in FIG. 2 described above. A PDN GW communication unit 501 transmits and receives data between the MME 204a and a PDN GW. A base station communication unit 502 transmits and receives data via the S1 interface between the MME 204a and a base station 203. If the data received from the PDN GW is user data, the user data is passed from the PDN GW communication unit 501 to the base station communication unit 502 via a user plane communication unit 503, and transmitted to one or more base stations 203. If the data received from the base station 203 is user data, the user data is passed from the base station communication unit 502 to the PDN GW communication unit 501 via the user plane communication unit 503, and transmitted to the PDN GW.

[0093] If the data received from the PDN GW is control data, the control data is passed from the PDN GW communication unit 501 to the control plane control unit 505. If the data received from the base station 203 is control data, the control data is passed from the base station communication unit 502 to the control plane control unit 505.

[0094] The control plane control unit 505 includes a NAS security unit 505-1, an SAE bearer control unit 505-2, an idle state mobility management unit 505-3, etc., and performs overall processing for the control plane (hereinafter sometimes referred to as the C-Plane). The NAS security unit 505-1 performs security for NAS (Non-Access Stratum) messages, etc. The SAE bearer control unit 505-2 performs management of SAE (System Architecture Evolution) bearers, etc. The idle state mobility management unit 505-3 performs mobility management in the idle state (also referred to as the LTE-IDLE state or simply idle), generation and control of paging signals in the idle state, addition, deletion, update, and search of tracking areas for one or more mobile terminals 202 under its control, tracking area list management, etc.

[0095] The MME 204a distributes paging signals to one or more base stations 203. The MME 204a also performs mobility control in an idle state. The MME 204a manages a tracking area list when the mobile terminal is in an idle state and an active state. The MME 204a initiates a paging protocol by transmitting a paging message to a cell belonging to a tracking area in which the UE is registered. The idle state mobility management unit 505-3 may manage the CSG, CSG ID, and whitelist of the eNB 207 connected to the MME 204a.

[0096] FIG. 11 is a block diagram showing the configuration of 5GC. FIG. 11 shows the configuration of the 5GC unit 214 shown in FIG. 3 described above. FIG. 11 shows a case where the 5GC unit 214 shown in FIG. 5 includes an AMF configuration, an SMF configuration, and a UPF configuration. The Data Network communication unit 521 transmits and receives data between the 5GC unit 214 and the Data Network. The base station communication unit 522 transmits and receives data via the S1 interface between the 5GC unit 214 and the base station 203, and / or the NG interface between the 5GC unit 214 and the base station 213. If the data received from the Data Network is user data, the user data is passed from the Data Network communication unit 521 to the base station communication unit 522 via the user plane communication unit 523, and transmitted to one or more base stations 203 and / or base stations 213. If the data received from base station 203 and / or base station 213 is user data, the user data is passed from base station communication unit 522 to data network communication unit 521 via user plane communication unit 523 and transmitted to the data network.

[0097] If the data received from the Data Network is control data, the control data is passed from the Data Network communication unit 521 to the session management unit 527 via the user plane communication unit 523. The session management unit 527 passes the control data to the control plane control unit 525. If the data received from the base station 203 and / or base station 213 is control data, the control data is passed from the base station communication unit 522 to the control plane control unit 525. The control plane control unit 525 passes the control data to the session management unit 527.

[0098] The control plane control unit 525 includes a NAS security unit 525-1, a PDU session control unit 525-2, an idle state mobility management unit 525-3, etc., and performs overall processing for the control plane (hereinafter sometimes referred to as the C-Plane). The NAS security unit 525-1 performs security for NAS (Non-Access Stratum) messages, etc. The PDU session control unit 525-2 performs management of PDU sessions between the mobile terminal 202 and the 5GC unit 214, etc. The idle state mobility management unit 525-3 performs mobility management in the idle state (also referred to as the RRC_IDLE state or simply idle), generation and control of paging signals in the idle state, addition, deletion, update, and search of tracking areas for one or more mobile terminals 202 under its control, tracking area list management, etc.

[0099] The 5GC unit 214 distributes paging signals to one or more base stations 203 and / or base station 213. The 5GC unit 214 also performs mobility control in an idle state. The 5GC unit 214 manages a tracking area list when the mobile terminal is in an idle state, an inactive state, or an active state. The 5GC unit 214 initiates a paging protocol by transmitting a paging message to a cell belonging to a tracking area in which the UE is registered.

[0100] Next, an example of a cell search method in a communication system is shown. Fig. 12 is a flowchart showing an outline of the process from cell search to standby operation performed by a communication terminal (UE) in an LTE communication system. When the communication terminal starts a cell search, in step ST601, it synchronizes slot timing and frame timing using a primary synchronization signal (P-SS) and a secondary synchronization signal (S-SS) transmitted from a surrounding base station.

[0101] P-SS and S-SS are collectively called the Synchronization Signal (SS). The Synchronization Signal (SS) is assigned a synchronization code that corresponds one-to-one to the PCI assigned to each cell. 504 different PCIs are being considered. These 504 different PCIs are used to achieve synchronization and to detect (identify) the PCI of the synchronized cell.

[0102] Next, in step ST602, for the synchronized cell, a cell-specific reference signal (CRS), which is a reference signal (RS) transmitted from the base station for each cell, is detected and the RS received power (Reference Signal Received Power: RSRP) is measured. The RS uses a code that has a one-to-one correspondence with the PCI. By correlating with this code, it is possible to separate the cell from other cells. By deriving the code for the RS of the cell from the PCI identified in step ST601, it is possible to detect the RS and measure the RS received power.

[0103] Next, in step ST603, the cell with the best RS reception quality, for example, the cell with the highest RS reception power, that is, the best cell, is selected from one or more cells detected up to step ST602.

[0104] Next, in step ST604, the PBCH of the best cell is received to obtain the BCCH, which is broadcast information. A MIB (Master Information Block), which includes cell configuration information, is mapped to the BCCH on the PBCH. Therefore, the MIB can be obtained by receiving the PBCH and obtaining the BCCH. Examples of MIB information include the DL (downlink) system bandwidth (also called transmission bandwidth configuration: dl-bandwidth), the number of transmitting antennas, and the SFN (System Frame Number).

[0105] Next, in step ST605, the DL-SCH of the cell is received based on the cell configuration information in the MIB, and SIB (System Information Block) 1 is obtained from the broadcast information BCCH. SIB 1 includes information on access to the cell, information on cell selection, and scheduling information for other SIBs (SIBk; k is an integer greater than or equal to 2). SIB 1 also includes a tracking area code (TAC).

[0106] Next, in step ST606, the communication terminal compares the TAC of the SIB1 received in step ST605 with the TAC portion of the tracking area identity (TAI) in the tracking area list that the communication terminal already holds. The tracking area list is also called a TAI list. The TAI is identification information for identifying a tracking area, and is composed of an MCC (Mobile Country Code), an MNC (Mobile Network Code), and a TAC (Tracking Area Code). The MCC is a country code. The MNC is a network code. The TAC is a tracking area code number.

[0107] If the comparison in step ST606 shows that the TAC received in step ST605 is the same as the TAC included in the tracking area list, the communication terminal enters standby mode in the cell. If the comparison shows that the TAC received in step ST605 is not included in the tracking area list, the communication terminal requests a core network (EPC) including an MME, etc., to change the tracking area in order to perform a Tracking Area Update (TAU) through the cell.

[0108] In the example shown in Fig. 12, an example of operations from cell search to standby in the LTE system is shown, but in the NR system, in addition to the best cell, the best beam may be selected in step ST603. Also, in the NR system, beam information, for example, a beam identifier, may be acquired in step ST604. Also, in the NR system, scheduling information of remaining minimum SI (RMSI) may be acquired in step ST604. In the NR system, RMSI may be received in step ST605.

[0109] An apparatus constituting a core network (hereinafter sometimes referred to as a "core network side apparatus") updates the tracking area list based on the identification number (e.g., UE-ID) of the communication terminal sent from the communication terminal together with a TAU request signal. The core network side apparatus transmits the updated tracking area list to the communication terminal. The communication terminal rewrites (updates) the TAC list held by the communication terminal based on the received tracking area list. Thereafter, the communication terminal enters standby operation in the cell.

[0110] The widespread use of smartphones and tablet devices has led to an explosive increase in cellular wireless communication traffic, raising concerns about a shortage of wireless resources worldwide. In response to this, efforts are being made to develop small cells and promote spatial separation in order to improve frequency utilization efficiency.

[0111] In a conventional cell configuration, a cell configured by an eNB has a relatively wide coverage area. Conventionally, a cell is configured so that a certain area is covered by the relatively wide coverage areas of multiple cells configured by multiple eNBs.

[0112] In the case of small cell configuration, a cell configured by an eNB has a narrower coverage area than a cell configured by a conventional eNB. Therefore, as in the past, a larger number of small cell configuration eNBs are required to cover a certain area compared to conventional eNBs.

[0113] In the following description, a cell with a relatively large coverage, such as a cell configured by a conventional eNB, is referred to as a "macro cell," and an eNB that configures the macro cell is referred to as a "macro eNB." Also, a cell with a relatively small coverage, such as a cell configured as a small cell, is referred to as a "small cell," and an eNB that configures the small cell is referred to as a "small eNB."

[0114] The macro eNB may be, for example, a "Wide Area Base Station" as described in Non-Patent Document 7.

[0115] The small eNB may be, for example, a low-power node, a local area node, a hotspot, etc. Also, the small eNB may be a pico eNB constituting a pico cell, a femto eNB constituting a femto cell, a HeNB, a remote radio head (RRH), a remote radio unit (RRU), a remote radio equipment (RRE), or a relay node (RN). Also, the small eNB may be a "local area base station" or a "home base station" as described in Non-Patent Document 7.

[0116] FIG. 13 shows an example of a cell configuration in NR. In an NR cell, narrow beams are formed and transmitted while changing direction. In the example shown in FIG. 13, at a certain time, base station 750 transmits and receives signals to and from a mobile terminal using beam 751-1. At another time, base station 750 transmits and receives signals to and from a mobile terminal using beam 751-2. In a similar manner, base station 750 transmits and receives signals to and from a mobile terminal using one or more of beams 751-3 to 751-8. In this way, base station 750 configures a wide-area cell.

[0117] 13 shows an example in which the number of beams used by the base station 750 is 8, but the number of beams may be different from 8. Also, in the example shown in FIG. 13, the number of beams used simultaneously by the base station 750 is 1, but it may be multiple.

[0118] 3GPP supports Side Link (SL) for D2D (Device to Device) communication and V2V (Vehicle to Vehicle) communication (see Non-Patent Document 1 and Non-Patent Document 16). SL is defined by the PC5 interface.

[0119] The physical channels used for SL (see Non-Patent Document 1) will be described below. A physical sidelink broadcast channel (PSBCH) carries information related to the system and synchronization, and is transmitted from a UE.

[0120] The physical sidelink discovery channel (PSDCH) carries sidelink discovery messages from the UE.

[0121] The physical sidelink control channel (PSCCH) carries control information from the UE for sidelink and V2X sidelink communications.

[0122] The physical sidelink shared channel (PSSCH) carries data from the UE for sidelink and V2X sidelink communications.

[0123] The physical sidelink feedback channel (PSFCH) carries HARQ feedback on the sidelink from UEs that receive a PSSCH transmission to the UE that transmitted the PSSCH.

[0124] The transport channel used for SL (see Non-Patent Document 1) will be described below. The sidelink broadcast channel (SL-BCH) has a predetermined transport format and is mapped to the PSBCH, which is a physical channel.

[0125] The Sidelink Discovery Channel (SL-DCH) has periodic broadcast transmissions of a fixed size and a predetermined format. The SL-DCH supports both UE autonomous resource selection and eNB-scheduled resource allocation. UE autonomous resource selection involves a collision risk, whereas when the UE is allocated dedicated resources by the eNB, there is no collision. The SL-DCH supports HARQ combining but not HARQ feedback. The SL-DCH is mapped to the PSDCH, a physical channel.

[0126] The Sidelink Shared Channel (SL-SCH) supports broadcast transmission. It supports both UE autonomous resource selection and eNB-scheduled resource allocation. While UE autonomous resource selection involves a collision risk, there is no collision when the UE is allocated dedicated resources by the eNB. The SL-SCH also supports HARQ combining but not HARQ feedback. The SL-SCH also supports dynamic link adaptation by varying transmit power, modulation, and coding. The SL-SCH is mapped to the PSSCH, a physical channel.

[0127] The logical channels used for SL (see Non-Patent Document 1) will be described. The Sidelink Broadcast Control Channel (SBCCH) is a sidelink channel for broadcasting sidelink system information from one UE to other UEs. The SBCCH is mapped to the SL-BCH, which is a transport channel.

[0128] The Sidelink Traffic Channel (STCH) is a point-to-multipoint traffic channel for transmitting user information from one UE to other UEs. The STCH is used only by UEs with sidelink communication capability and UEs with V2X sidelink communication capability. Point-to-point communication between two sidelink-capable UEs is also realized by the STCH. The STCH is mapped to the SL-SCH, a transport channel.

[0129] The Sidelink Control Channel (SCCH) is a control channel for transmitting control information from one UE to another UE. The SCCH is mapped to the SL-SCH, which is a transport channel.

[0130] 3GPP is considering supporting V2X communication in NR as well. The study of V2X communication in NR is being carried out based on the LTE system and LTE-A system, but the following changes and additions have been made from the LTE system and LTE-A system.

[0131] In LTE, SL communication was limited to broadcast. In NR, support for unicast and groupcast as SL communication in addition to broadcast is being considered (see Non-Patent Document 21 (TS23.287)).

[0132] For unicast and groupcast communications, support for HARQ feedback (Ack / Nack), CSI reporting, etc. is being considered.

[0133] In order to support unicast and groupcast in addition to broadcast in SL communication, support for PC5-S signaling is being considered (see Non-Patent Document 21 (TS23.287)). For example, PC5-S signaling is implemented to establish a link for implementing SL, i.e., PC5 communication. This link is implemented in the V2X layer and is also called a Layer 2 link.

[0134] Furthermore, support for RRC signaling in SL communication is being considered (see Non-Patent Document 21 (TS23.287)). RRC signaling in SL communication is also referred to as PC5 RRC signaling. For example, it has been proposed to notify UE capabilities between UEs performing PC5 communication, and to notify AS layer settings for V2X communication using PC5 communication.

[0135] The UE may request the serving base station to set or change a measurement gap. The request may be made, for example, during positioning using Multi-RTT. The serving base station may use the request to determine a measurement gap for the UE. The serving base station may instruct the UE to set a measurement gap. The UE may set a measurement gap using the instruction from the serving base station. The UE may use the set measurement gap to transmit and receive positioning signals between the serving base station and neighboring base stations.

[0136] In the above, the following problem occurs: A request to set or change the measurement gap is made after the start of positioning, in other words, after the LMF requests the UE to transmit or receive a positioning signal, which increases the latency in positioning.

[0137] A solution to the aforementioned problem is disclosed.

[0138] The serving base station may instruct the UE to set a measurement gap without waiting for a request from the UE. The UE may not request setting or changing the measurement gap. The UE may use the instruction to set a measurement gap.

[0139] The serving base station acquires information about positioning signals from neighboring base stations. The positioning signals may be, for example, PRSs. The information about the positioning signals may be, for example, information about time and / or frequency resources on which the positioning signals are transmitted. The serving base station may use the information to determine measurement gaps for the UE. For example, the serving base station may set measurement gaps so that the UE can receive positioning signals from all base stations used for positioning the UE. The serving base station may instruct the UE to set the determined measurement gaps. The UE may use the instruction to set measurement gaps. This, for example, eliminates the need for the UE to determine measurement gaps, thereby reducing the amount of processing in the UE.

[0140] The serving base station may obtain this information from the LMF. The LMF may notify the serving base station of information related to the positioning signals of neighboring base stations. For example, the NRPPa MEASUREMENT REQUEST disclosed in Non-Patent Document 22 (TS38.305 V16.0.0) may be used for the notification from the LMF to the serving base station. The LMF may include information related to the positioning signals of neighboring base stations in the notification to the serving base station. This may, for example, reduce the amount of signaling between the LMF and the serving base station.

[0141] As another example, new signaling (e.g., NRPPa MEASUREMENT REQUEST for serving gNB) may be provided for the notification, which makes it possible to distinguish between signaling for neighboring base stations and signaling for the serving base station, thereby avoiding complexity in the communication system.

[0142] As another example, the notification may use the NRPPa POSITIONING INFORMATION REQUEST disclosed in Non-Patent Document 22 (TS38.305), which allows the serving base station to quickly obtain information about the positioning signals of neighboring base stations.

[0143] As another example, the notification may be performed in the procedure of NRPPa DL PRS CONFIGURATION INFORMATION EXCHANGE disclosed in Non-Patent Document 22 (TS38.305). This allows, for example, the serving base station to more quickly obtain the information regarding the positioning signals of neighboring base stations. The notification may be made directly from the neighboring base station to the serving base station, or may be made from the neighboring base station to the serving base station via the LMF. The notification may be made from the LMF to the serving base station. The serving base station may request the notification from the neighboring base station. The request may be made directly from the serving base station to the neighboring base station, or may be made from the serving base station to the neighboring base station via the LMF. The request may be made from the LMF to the neighboring base station.

[0144] The following items (1) to (5) are disclosed as information relating to the positioning signals of the surrounding base stations.

[0145] (1) Information about surrounding base stations.

[0146] (2) Information regarding the type of positioning signal.

[0147] (3) Information regarding positioning signal settings.

[0148] (4) Information about the frame timing of surrounding base stations.

[0149] (5) A combination of (1) to (4) above.

[0150] The information related to (1) above may be, for example, the identifier of the base station or the identifier of the cell of the base station. The identifier of the cell may be, for example, a PCI or a global cell ID. The serving base station may use this information to identify the base station or cell used for UE positioning. This may, for example, reduce the complexity of the process of determining the measurement gap for the UE in the serving base station.

[0151] The information related to (2) above may be, for example, a PRS, an SS block, a CSI-RS, or a DM-RS. The serving base station may use this information to recognize the type of positioning signal used for UE positioning. This may, for example, reduce the complexity of the serving base station's process for determining the measurement gap for the UE.

[0152] The information regarding (3) above may be, for example, information regarding the time and / or frequency resources of the positioning signal. The information may include information regarding the slot, subframe, and / or frame in which the base station transmits the positioning signal. The serving base station may use the information to obtain information regarding the time and / or frequency resources of the positioning signals of neighboring base stations. This allows the serving base station to quickly determine the measurement gap for the UE, for example.

[0153] The information regarding (4) above may be, for example, information regarding the difference in frame timing between a neighboring base station and a serving base station. The information may be provided using, for example, a frame unit, a subframe unit, a slot unit, a symbol unit, a basic unit of time in NR (e.g., Tc described in Non-Patent Document 13 (TS38.211)), and / or a basic unit of time in LTE (e.g., Ts described in Non-Patent Document 13 (TS38.211)). As another example, the information may be information associating a specific frame, subframe, slot, and / or symbol in the neighboring base station with a time. The associated information may be, for example, the time at the beginning or end of a specific frame. The information may be combined with information on the frame number in the neighboring base station. This allows, for example, the serving base station to ascertain the timing of transmitting and receiving positioning signals to and from the neighboring base station.

[0154] 14 and 15 are sequences showing a first example of positioning operations when a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE. Figures 14 and 15 are connected at the boundary line BL1415. Figures 14 and 15 show the case of Multi-RTT. Figures 14 and 15 show an example in which an LMF notifies a serving base station of information about neighboring base stations. Figures 14 and 15 show an example in which the serving base station is a serving gNB / TRP and the neighboring base stations are neighboring gNB / TRPs. Figures 14 and 15 show an example in which a PRS is used as a downlink positioning signal and an SRS is used as an uplink positioning signal.

[0155] In step ST1401 shown in FIG. 14, information regarding PRS configuration is exchanged between the LMF, the serving base station, and the surrounding base stations. The LMF may request information regarding PRS configuration from the serving base station and / or the surrounding base station. The serving base station and / or the surrounding base station may notify the LMF of the information. For example, the request and / or the notification may use signaling of the NRPPa Message described in Non-Patent Document 22 (TS38.305). The notification from the serving base station and / or the surrounding base station to the LMF may include, for example, the information disclosed in Table 8.10.2.3-1 of Non-Patent Document 22 (TS38.305).

[0156] In step ST1403 shown in FIG. 14, information about positioning capabilities is exchanged between the LMF and the UE. The LMF may request information about positioning capabilities from the UE. The UE may notify the LMF of the information. For the request and / or the notification, for example, signaling of LPP Request Capabilities and / or LPP Provide Capabilities described in Section 7.1.2.1 of Non-Patent Document 29 (TS36.305) and Non-Patent Document 24 (TS37.355) may be used.

[0157] The notification from the LMF to the UE in ST1403 shown in FIG. 14 may include, for example, information on whether the UE can calculate its position. This makes it possible to reduce, for example, the latency of positioning. This information may be provided for each positioning method (for example, Multi-RTT, DL-TDOA (Downlink-Time Difference of Arrival)). This makes it possible, for example, to improve the flexibility of the communication system.

[0158] 14, the LMF requests information about uplink SRS from the serving base station. For this request, for example, signaling of NRPPa POSITIONING INFORMATION REQUEST disclosed in Non-Patent Document 22 (TS38.305) may be used.

[0159] In step ST1407 shown in FIG. 14, the serving base station may determine information regarding the SRS transmission resources of the UE. The above-mentioned SRS transmission resources may be, for example, frequency resources, time resources, information regarding code sequences, or a combination of the above-mentioned pieces of information. In step ST1409, the serving base station instructs the UE to configure the SRS transmission resources. For example, RRCReconfiguration signaling may be used for this instruction. The SRS transmission configured for the UE may be periodic SRS transmission, semi-persistent SRS transmission, or aperiodic SRS transmission. The UE may configure the SRS using this instruction.

[0160] 14, the serving base station notifies the LMF of information related to the uplink SRS. For this notification, for example, signaling of NRPPa POSITIONING INFORMATION RESPONSE disclosed in Non-Patent Document 22 (TS38.305) may be used.

[0161] In step ST1413 shown in Fig. 14, the serving base station instructs the UE to activate SRS transmission. This instruction may be performed by RRC signaling, MAC signaling, or L1 / L2 signaling. The UE starts SRS transmission using this instruction.

[0162] In step ST1414 shown in FIG. 14, the LMF requests the serving base station to measure a positioning signal. The request may include information about neighboring base stations. For example, NRPPa signaling may be used for the request. For the NRPPa signaling, new signaling (for example, NRPPa MEASUREMENT REQUEST for serving gNB) may be used, or the NRPPa MEASUREMENT REQUEST disclosed in Non-Patent Document 22 (TS38.305 V16.0.0) may be used. Information about neighboring base stations may be included in the signaling of the NRPPa MEASUREMENT REQUEST.

[0163] In step ST1415 shown in Fig. 14, the LMF requests neighboring base stations to measure positioning signals. For example, NRPPa signaling may be used for this request. For example, NRPPa MEASUREMENT REQUEST disclosed in Non-Patent Document 22 (TS38.305 V16.0.0) may be used for this NRPPa signaling.

[0164] In Step ST1417 shown in Fig. 14, the serving base station instructs the UE to configure measurement gaps. The serving base station may determine the configuration of measurement gaps for the UE by using, for example, information about neighboring base stations acquired in Step ST1414. The UE configures measurement gaps for its own UE by using Step ST1417.

[0165] In step ST1419 shown in FIG. 14, the LMF notifies the UE of information used for positioning. The information may be, for example, information about the downlink PRS of the serving base station and / or neighboring base stations, information about frame timing, or a combination of the above. For example, LPP signaling may be used to notify the information. The LPP signaling may be, for example, LPP Provide Assistance Data disclosed in Non-Patent Document 22 (TS38.305 V16.0.0).

[0166] In step ST1421 shown in Fig. 14, the LMF requests the UE to perform positioning. For example, LPP signaling may be used for this request. For example, the LPP signaling may be LPP Request Location Information disclosed in Non-Patent Document 22 (TS38.305 V16.0.0). The UE uses this request to perform measurement processing of the PRS.

[0167] In Step ST1422 shown in Fig. 15, the UE performs reception processing of the PRS signal from the serving base station and / or the surrounding base station. In Step ST1423, the serving base station and / or the surrounding base station performs reception processing of the SRS signal from the UE.

[0168] 15, the UE notifies the LMF of information related to the reception result of the positioning signal. For example, LPP signaling may be used for this notification. The LPP signaling may be, for example, LPP Provide Location Information disclosed in Non-Patent Document 22 (TS38.305 V16.0.0).

[0169] In Step ST1427 shown in FIG. 15, the serving base station and / or neighboring base station notifies the LMF of information related to the reception result of the positioning signal. For example, NRPPa signaling may be used for this notification. For example, the NRPPa MEASUREMENT RESPONSE disclosed in Non-Patent Document 22 (TS38.305) may be used for this NRPPa signaling. In Step ST1429, the LMF calculates the position of the UE.

[0170] In Step ST1434 shown in FIG. 15, the UE requests the serving base station to change the measurement gap. The request may be a request to restore the measurement gap to the setting before positioning. RRC signaling, for example, RRC Location Measurement Indication disclosed in Non-Patent Document 22 (TS38.305), may be used for the request. The request may include information regarding the suspension of the measurement gap for positioning. In Step ST1435, the serving base station may instruct the UE to set the measurement gap. In Step ST1435, the same signaling as in Step ST1417 may be used.

[0171] 14 and 15 show an example in which the LMF notifies the serving base station of information about neighboring base stations in step ST1414, but the LMF may also notify the information in step ST1405. For example, the LMF may include the information about neighboring base stations in the signaling of an NRPPa POSITIONING INFORMATION REQUEST disclosed in Non-Patent Document 22 (TS38.305) and notify the serving base station. The LMF may transmit signaling similar to that in step ST1415 to the serving base station instead of the signaling in step ST1414. This makes it possible to avoid, for example, complexity related to communication signaling.

[0172] 14 and 15 show an example in which the LMF notifies the serving base station of information about neighboring base stations in step ST1414, but the information about neighboring base stations may be notified to the serving base station in step ST1401. In this case, the LMF may perform the processing of step ST1415 to the serving base station instead of the processing of step ST1414. This enables the serving base station to quickly obtain information about neighboring base stations, for example.

[0173] 14 and 15 show an example in which the serving base station instructs the UE to set a measurement gap in step ST1417, but step ST1417 may be performed after step ST1419 or after step ST1421. This allows, for example, transmission in step ST1419 and / or step ST1421 to be performed before the measurement gap is changed. As a result, it is possible to avoid complexity in the communication system.

[0174] 14 and 15 show the case where the serving base station calculates the measurement gap, but the LMF may also calculate the measurement gap. The LMF may notify the serving base station of information regarding the determined measurement gap. For the notification from the LMF to the serving base station, for example, signaling of NRPPa MEASUREMENT REQUEST for serving gNB may be used, or new signaling may be provided. This may, for example, reduce the amount of processing in the serving base station.

[0175] As another example of the serving base station acquiring information about the positioning signals of neighboring base stations, the serving base station may acquire the information from the neighboring base stations. The neighboring base stations may notify the serving base station of the information about the positioning signals of the neighboring base stations. The notification may be performed using an inter-base station interface, for example, an Xn interface. Alternatively, the notification may be performed via an AMF, for example, using an N2 interface. This may reduce the amount of processing in the LMF, for example.

[0176] Figures 16 and 17 show a sequence illustrating a second example of positioning operations when a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE. Figures 16 and 17 are connected at the position of boundary line BL1617. Figures 16 and 17 illustrate the case where Multi-RTT is performed. In Figures 16 and 17, the same steps as in Figures 14 and 15 are assigned the same step numbers, and common explanations will be omitted.

[0177] Steps ST1401 to ST1413 shown in FIG. 16 are the same as those in FIG.

[0178] 16, the LMF requests the serving base station and neighboring base stations to measure the positioning signal. For this request, the same signaling as in step ST1415 in FIG.

[0179] In step ST1516 shown in FIG. 16 , the neighboring base station notifies the serving base station of information related to its own base station. For example, Xn signaling may be provided for the notification. New Xn signaling may be provided (for example, gNB configuration notification). The serving base station may use the information to obtain information related to the neighboring base stations.

[0180] Steps ST1417 to ST1435 shown in FIGS. 16 and 17 are the same as those in FIGS.

[0181] A base station may have an LMF. The base station with the LMF may be, for example, a serving base station. The serving base station may derive the location of the UE using measurements from the UE and / or neighboring base stations.

[0182] Figures 18 and 19 are sequence diagrams showing the operation of Multi-RTT when the serving base station has an LMF. Figures 18 and 19 are connected at the position of boundary line BL1819. Figures 18 and 19 show an example in which a UE requests a base station to set measurement gaps for positioning, and the base station instructs the UE to set measurement gaps. In Figures 18 and 19, the same steps as in Figures 14 to 17 are assigned the same step numbers, and common explanations will be omitted.

[0183] In step ST1601 in FIG. 18, information related to PRS configuration is exchanged between the serving base station and the neighboring base station. Information related to the neighboring base stations may be exchanged, or the above-mentioned plurality of pieces of information may be exchanged. The serving base station may request the information from the neighboring base station. The neighboring base station may notify the serving base station of the information. For the request and / or the notification, for example, NRPPa Message signaling described in Non-Patent Document 22 (TS38.305) or Xn signaling may be used. The notification from the neighboring base station to the serving base station may include, for example, the information disclosed in Table 8.10.2.3-1 of Non-Patent Document 22 (TS38.305).

[0184] Step ST1403 in Fig. 18 is the same as that in Fig. 14. In Step ST1403 in Fig. 18, information on positioning capabilities may be exchanged between the serving base station and the UE. LPP signaling may be used for the signaling in Step ST1403 in Fig. 18, as with the signaling in Step ST1403 in Fig. 14. The LPP signaling in Step ST1403 in Fig. 18 may be notified over RRC signaling.

[0185] In Fig. 18, the process of step ST1405 in Fig. 14 may not be performed. Steps ST1407 and ST1409 in Fig. 18 are the same as those in Fig. 14.

[0186] In Fig. 18, the process of step ST1411 in Fig. 14 may not be performed. Step ST1413 in Fig. 16 is the same as in Fig. 14.

[0187] In Step ST1615 shown in Fig. 18, the serving base station requests the neighboring base stations to measure positioning signals. For this request, NRPPa signaling similar to that of Step ST1415 shown in Fig. 14 may be used. The signaling of Step ST1615 may be notified using, for example, the Xn interface.

[0188] In Step ST1619 shown in Fig. 18, the serving base station notifies the UE of information used for positioning. This information may be the same as that in Step ST1419 in Fig. 14, for example. The request may use the same signaling as that in Step ST1419 in Fig. 14. The LPP signaling in Step ST1619 may be notified over RRC signaling, for example.

[0189] In Step ST1621 shown in Fig. 18, the serving base station requests the UE to perform positioning. The request may be made using the same signaling as in Step ST1421 in Fig. 14. The LPP signaling in Step ST1621 may be notified by, for example, RRC signaling. The UE uses Step ST1621 to start receiving downlink positioning signals from the serving base station and / or neighboring base stations.

[0190] In Step ST1623 shown in FIG. 18, the UE requests the serving base station to change the measurement gap. For this request, RRC signaling, for example, RRC Location Measurement Indication disclosed in Non-Patent Document 22 (TS38.305), may be used. The request may include information regarding the start of the positioning measurement gap. In Step ST1625, the serving base station may instruct the UE to set the measurement gap. In Step ST1625, the same signaling as in Step ST1417 shown in FIG. 14 may be used.

[0191] In step ST1627 shown in Fig. 19, the peripheral base station notifies the serving base station of information related to the reception result of the positioning signal. The information included in the notification may be the same as that in step ST1427 in Fig. 15. For example, NRPPa signaling may be used for the notification. For example, the signaling may be notified using the Xn interface.

[0192] 19, the serving base station calculates the location of the UE. The serving base station may calculate the location of the UE by using the information in Step ST1425 and / or Step ST1629.

[0193] Steps ST1434 and ST1435 shown in FIG. 19 are the same as those in FIG.

[0194] The method disclosed in the first embodiment may be applied to a case where a base station has an LMF. For example, a serving base station may set a measurement gap for a UE without a measurement gap setting request from the UE.

[0195] Figures 20 and 21 show sequences of a positioning method in which a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE when the base station has an LMF. Figures 20 and 21 are connected at the position of a boundary line BL2021. Figures 20 and 21 show an example in which Multi-RTT is used. In Figures 20 and 21, the same steps as in Figures 14 to 19 are assigned the same step numbers, and common explanations will be omitted.

[0196] Steps ST1601 to ST1615 shown in FIG. 20 are the same as those in FIG.

[0197] In Step ST1717 shown in Fig. 20, the serving base station instructs the UE to set a measurement gap. This instruction may be the same as in Step ST1417 in Fig. 14.

[0198] Steps ST1619 to ST1435 shown in FIGS. 20 and 21 are the same as those in FIGS.

[0199] The UE may have an LMF. The UE may derive its location using measurements from its own UW and / or surrounding base stations.

[0200] The UE may request the serving base station and / or a neighboring base station to start transmitting and receiving the positioning signal. That is, the request to start transmitting and receiving the positioning signal may be initiated by the UE. The UE may make the request to the neighboring base station via the serving base station. The neighboring base station and / or the serving base station may use the request to start transmitting and receiving the positioning signal.

[0201] The UE may make the request at any timing of the UE, for example, at a timing when the processing load of the UE is small, which may reduce the processing load of the UE during positioning, for example.

[0202] The UE may also issue a measurement gap setting request to the serving base station at any timing of the UE, for example, at a timing when the processing load of the UE is low. This can provide, for example, the same effects as those described above.

[0203] Figures 22 and 23 are sequence diagrams showing the operation of Multi-RTT when the UE has an LMF. Figures 22 and 23 are connected at the position of boundary line BL2223. Figures 22 and 23 show an example in which the UE requests the base station to set measurement gaps for positioning, and the base station instructs the UE to set the measurement gaps. In Figures 22 and 23, the same steps as in Figures 14 to 21 are assigned the same step numbers, and common explanations will be omitted.

[0204] Step ST1401 in FIG. 22 is the same as that in FIG. 14. In Step ST1401 in FIG. 22, information regarding the configuration of PRSs is exchanged between the UE, the serving base station, and the neighboring base station. The UE may request information regarding the configuration of PRSs from the serving base station. The serving base station may notify the UE of the information. The serving base station may forward the request to the neighboring base station. The neighboring base station may notify the serving base station of the information. The serving base station may forward the information of the neighboring base station to the UE. The serving base station may notify the UE of the information of the neighboring base station by including it in a notification of the information from its own base station. For the request and / or the notification, for example, signaling of the NRPPa Message described in Non-Patent Document 22 (TS38.305) may be used. The NRPPa signaling may be transmitted using RRC signaling and / or Xn signaling. The notification from the serving base station and / or the neighboring base station may include the same information as in Step ST1401 in FIG. 14.

[0205] Step ST1403 in FIG. 22 is the same as in FIG.

[0206] Although an example of performing the process of step ST1403 has been described in FIG. 22, this step ST1403 may be omitted. The LMF unit included in the UE may acquire a capability related to positioning of the UE within the UE. This makes it possible to reduce signaling between the base station and the UE, for example.

[0207] In Step ST1805 in Fig. 22, the UE requests information about uplink SRS from the serving base station. For this request, the same signaling as in Step ST1405 in Fig. 14, for example, NRPPa signaling, may be used. The signaling in Step ST1805 may be transmitted using RRC signaling.

[0208] Although an example of performing the process of step ST1805 is described in FIG. 22, this step ST1805 may be omitted. The LMF unit included in the UE may acquire the SRS setting of the UE within the UE. This makes it possible to reduce, for example, signaling between the base station and the UE.

[0209] Steps ST1407 to ST1413 shown in FIG. 22 are the same as those in FIG.

[0210] In Step ST1814 shown in Fig. 22, the UE requests the serving base station to measure a positioning signal. The request may include information about neighboring base stations. For example, NRPPa signaling may be used for the request. The NRPPa signaling may be the same as, for example, Step ST1414 in Fig. 14. For example, the signaling of Step ST1814 may be transmitted to the serving base station using RRC signaling.

[0211] Step ST1615 shown in FIG. 22 is the same as that in FIG.

[0212] Steps ST1623 and ST1625 shown in FIG. 22 are the same as those in FIG.

[0213] Step ST1422 shown in Fig. 23 is the same as in Fig. 15. Steps ST1423 and ST1427 are the same as in Fig. 17.

[0214] In Step ST1827 shown in Fig. 23, the serving base station notifies the UE of information related to the reception result of the positioning signal. For this notification, the same signaling as in Step ST1427 shown in Fig. 15 (for example, NRPPa signaling) may be used. This signaling may be transmitted using, for example, RRC signaling. In Step ST1829, the UE calculates the position of its own UE.

[0215] Steps ST1434 and ST1435 shown in FIG. 18 are the same as those in FIG.

[0216] The method disclosed in the first embodiment may be applied to a case where the UE has an LMF. For example, the serving base station may set a measurement gap for the UE without a measurement gap setting request from the UE.

[0217] Figures 24 and 25 show a sequence diagram illustrating a positioning method in which a serving base station sets a measurement gap for a UE without waiting for a measurement gap change request from the UE when the UE has an LMF. Figures 24 and 25 are connected at the position of boundary line BL2425. Figures 24 and 25 show an example in which Multi-RTT is performed. In Figures 24 and 25, the same steps as in Figures 14 to 23 are assigned the same step numbers, and common explanations will be omitted.

[0218] Steps ST1401 to ST1805 shown in FIG. 24 are the same as those in FIG.

[0219] Steps ST1407 to ST1413 shown in Fig. 24 are the same as those in Fig. 14. Step ST1814 is the same as that in Fig. 22. Step ST1615 is the same as that in Fig. 18.

[0220] Step ST1625 shown in Fig. 24 is the same as that in Fig. 22. Step ST1625 shown in Fig. 24 may be performed even if step ST1623 in Fig. 22 is omitted.

[0221] Steps ST1422 to ST1435 shown in FIG. 25 are the same as those in FIG.

[0222] In the method disclosed in the first embodiment, signaling of a positioning signal transmission / reception start request for a UE to request a measurement gap may be provided. This signal may be provided separately from the positioning signal transmission / reception start request (e.g., step ST1814) for transmitting / receiving a positioning signal between the UE and a serving base station and / or a peripheral base station. Using this request, the serving base station and / or the peripheral base station may transmit / receive a positioning signal to / from the UE, or may only transmit a positioning signal to the UE. For example, by transmitting only a positioning signal to the UE, it is possible to reduce power consumption in the UE.

[0223] The UE may determine a measurement gap to request from the serving base station using the positioning signal reception result from the serving base station and / or surrounding base stations. The UE may request a measurement gap from the serving base station. The UE may stop transmitting and receiving positioning signals to and from the serving base station and / or surrounding base stations. The serving base station may use the request to determine a measurement gap setting for the UE or to stop transmitting and receiving positioning signals to and from the UE. The serving base station may request the surrounding base stations to stop transmitting and receiving positioning signals. This request may be made, for example, using a measurement gap request from the UE. The surrounding base stations may use the request to stop transmitting and receiving positioning signals to and from the UE. After changing the measurement gap, the UE may request the serving base station to start transmitting and receiving positioning signals. The serving base station may forward the request to the surrounding base stations. The UE, the serving base station, and / or surrounding base stations may use the request to resume transmitting and receiving positioning signals. This may, for example, reduce power consumption in the UE, the serving base station, and / or surrounding base stations.

[0224] According to the first embodiment, it is possible to quickly perform positioning using round trip time.

[0225] Variation 1 of Embodiment 1 During positioning, the serving base station may inform the LMF of the beam used for communication with the UE, and the LMF may use the information to determine the frequency and / or time resources of the downlink positioning signal.

[0226] However, in positioning using Multi-RTT, neighboring base stations also use beams to send and receive positioning signals. In this case, since the neighboring base stations do not know the UE's location, they sweep multiple beams to send and receive positioning signals. This causes a problem: it takes time to send and receive positioning signals between the neighboring base stations and the UE, which results in increased latency in positioning.

[0227] In this first modification of the first embodiment, a method for solving the above-mentioned problems will be disclosed.

[0228] The LMF notifies neighboring base stations of information about the beam of the serving base station, which uses the information to transmit and receive positioning signals to and from the UE.

[0229] For example, the neighboring base station may perform beam sweeping within the range of the beam used by the serving base station for communication with the UE, and may transmit and receive positioning signals to and from the UE within the range.

[0230] The serving base station may perform beam sweeping of the beams used for positioning using information on the beams used for transmitting and receiving user data, which enables the serving base station to quickly perform positioning, for example.

[0231] The beam may be, for example, a beam used by a base station (e.g., a serving beam). The beam may be a beam for downlink transmission or a beam for uplink reception. For example, by using a beam for uplink reception, highly accurate positioning is possible even when the beam for downlink transmission and the beam for uplink reception do not match (beam correspondence is not achieved).

[0232] 26 is a diagram showing an operation in which a neighboring base station performs beam sweeping in the range of a beam used by a serving base station for communication with a UE. FIG. 26 shows an example in which a serving base station 2601 and a neighboring base station 2611 perform positioning of a UE 2605.

[0233] In the example shown in FIG. 26, serving base station 2601 is capable of using beams 2602, 2603, and 2604, and is assumed to communicate with UE 2605 using beam 2603.

[0234] 26, base station 2611 can use beams 2612, 2613, 2614, and 2615. Of these, beams 2613 and 2614 overlap with the range in which serving base station 2601 can communicate with UE 2605 using beam 2603. Therefore, base station 2611 performs positioning of UE 2605 using beams 2613 and 2614, which include the range in which communication is possible using beam 2603 from serving base station 2601. In other words, beams 2612 and 2615 are not used when base station 2611 performs positioning of UE 2605.

[0235] As another example, the serving base station may notify the base station performing positioning of information about the serving beam used for communication with the target UE, which may reduce the amount of processing in the LMF, for example.

[0236] The following (1) to (6) are disclosed as information regarding serving beams.

[0237] (1) Information about the location of the serving base station.

[0238] (2) Information about the direction of the center of the serving beam.

[0239] (3) Information about the beam's reach.

[0240] (4) Information about the beam width.

[0241] (5) Information about the serving beam's irradiation range.

[0242] (6) A combination of (1) to (5) above.

[0243] The information regarding (1) above may be, for example, the latitude, longitude, or altitude of the serving base station, or a combination of the above, which allows, for example, the base station performing positioning to determine the position of the serving base station with high accuracy.

[0244] As another example, the information related to (1) above may be information indicating in which region of a predefined region division the serving base station is located. The predefined region division may be, for example, one determined by a standard or one determined by the LMF. The region division may be performed using, for example, latitude and longitude, or altitude. The region divided by the region division may be, for example, triangular, rectangular, or hexagonal. This allows, for example, the serving base station to notify information about its own base station location in a small size.

[0245] As another example, the information regarding (1) above may be information regarding the difference in position between the serving base station and the base station performing positioning. The information regarding the difference may be, for example, a combination of the difference in the east-west direction, the difference in the north-south direction, and the difference in the altitude direction. Alternatively, the information regarding the difference may be, for example, a combination of the distance and azimuth angle between both base stations and the difference in altitude. Alternatively, the information regarding the difference may be, for example, a combination of the distance, azimuth angle, and elevation angle / depression angle between both base stations. This allows, for example, the serving base station to notify information regarding the position of its own base station in a small size, and the base station performing positioning to grasp the position of the serving base station with high accuracy.

[0246] The information regarding (2) above may be, for example, a combination of the azimuth angle of the center of the serving beam (e.g., information such as how many degrees clockwise from north) and the elevation angle / dip angle. Alternatively, the information regarding (2) above may be, for example, information on a vector described by horizontal components (e.g., a combination of north-south and east-west directions). The vector may also include an up-down component. This allows, for example, a base station performing positioning to determine the direction of the serving beam.

[0247] The information regarding (3) above may be, for example, the distance reached by the serving beam. The distance may be expressed in a predetermined unit (e.g., meters), or may be provided as information associating a predetermined parameter with the distance. This allows, for example, a base station performing positioning to estimate the range reached by the serving beam of the serving base station. As a result, the base station performing positioning can narrow down the range in which beam sweeping is performed. This allows the beam sweeping to be performed quickly.

[0248] The information regarding (4) above may be, for example, the half-width of the serving beam, which allows the base station performing positioning to estimate with high accuracy the coverage area of ​​the serving beam of the serving base station.

[0249] The information related to (5) above may be, for example, information indicating to which region in a predefined region division the communication range of the serving beam belongs. The predefined region division may be, for example, the same as the region division disclosed in (1) above. This allows, for example, the serving base station to notify information related to the communication range of the serving beam in a small size.

[0250] 27 is a diagram showing an example in which a serving base station notifies, as information about a serving beam, an area that overlaps with the range of the serving beam among a plurality of predetermined areas. In the example of FIG. 27, the communication area is divided into areas 2710 of a predetermined shape (here, a hexagon is exemplified), and the number of an area that overlaps with the range of the serving beam 2704 among the plurality of areas 2710 is used as information about the serving beam 2704.

[0251] In the example shown in FIG. 27 , a serving base station 2701 communicates with a UE 2705 using a serving beam 2704. The numbers of the areas in region 2710 that overlap with the range of the serving beam 2704 are 4, 7, 8, 12, 15, 16, and 19. The serving base station 2701 notifies the base station performing positioning of the numbers 4, 7, 8, 12, 15, 16, and 19 as the numbers of the areas 2710. Note that in the example shown in FIG. 27 , each of the areas 2710 numbered 4, 7, 8, 12, 15, 16, and 19 overlaps with a portion of the range of the serving beam (in other words, includes that portion). For example, depending on the size of the serving beam 2704 and region 2710 and the shape of region 2710, the entire range of the serving beam 2704 may be included in one region 2710.

[0252] The information about the serving beam may be notified using an interface between base stations (e.g., an Xn interface), via the AMF, or via the LMF. Beam sweeping of the beam used for positioning may be performed using information about the beam used for transmitting and receiving user data. This allows, for example, the serving base station to quickly perform positioning.

[0253] The base station performing positioning may use this information to derive the beam sweeping range of the beam that transmits the CSI-RS for positioning, for example, the base station may determine one or more beams that transmit the CSI-RS for positioning.

[0254] The base station performing the positioning may notify the UE performing the positioning of information about the positioning signal. The notification may be performed, for example, via the serving base station, the LMF, or the AMF. This allows, for example, the target UE to obtain information necessary for receiving the positioning signal, thereby enabling high-accuracy positioning in the communication system.

[0255] The information regarding the positioning signal may be, for example, the same as the information disclosed in Embodiment 1. The above-mentioned information may be provided for each beam used for transmitting and receiving the positioning signal.

[0256] Another solution is disclosed. A positioning signal may be transmitted from a base station used for positioning using an available beam at the base station. The available beam may be, for example, a beam that is not used in the base station for communication with a UE under its control. The positioning base station may notify the serving base station of information regarding the available beam at the base station. The serving base station may notify the UE of information regarding the available beam at the positioning base station. The UE may use the information to receive a positioning signal from the positioning base station. This, for example, makes it possible to shorten the beam sweeping time at the positioning base station and reduce interference from the positioning base station to a UE under its control.

[0257] Instead of the aforementioned empty beam, a beam with less interference may be used. The interference may be interference to a UE under the control of the beam, or interference received by a base station using the beam. The UE under the control of the beam may measure the interference power in the beam. The UE may report the measurement result of the interference power to the base station. The base station may use the report to determine the beam to be used for positioning. This may, for example, achieve the same effect as described above.

[0258] Another solution is disclosed. The UE may notify the serving base station of information regarding measurement results of neighboring base stations. The measurement results may include, for example, information regarding the beams of the neighboring base stations. The beam information may be, for example, a beam identifier of the CSI-RS, a beam identifier of the SS block, information regarding the reception quality (e.g., RSRQ, RSRP, SINR) of the beam, or a combination of the above. The serving base station may notify the neighboring base station of the beam-related information. The neighboring base station may use the information to determine the beam to be used for UE positioning. This may, for example, enable quick transmission and reception of positioning signals between the UE and the neighboring base station.

[0259] The above solutions may be combined. The base station performing positioning may perform beam sweeping in the range of the beam used by the serving base station for communication with the UE and in an available beam. This may further reduce the beam sweeping time in the positioning base station and reduce interference from the positioning base station to the UEs under its control.

[0260] The method disclosed in this first modification of the first embodiment may be used in handover, inter-DU switching, and / or inter-TRP switching. For example, the source base station may notify the destination base station of information on a serving beam to be used for connection with the UE. This information may be the same as the information disclosed in this first modification of the first embodiment. The source base station may use this information to determine a beam to be used for positioning of the UE. The same may be applied to inter-DU switching and / or inter-TRP switching. This makes it possible to quickly perform positioning after handover, for example.

[0261] According to this first modification of the first embodiment, the base station performing positioning can reduce the number of times it performs beam sweeping, thereby enabling the communication system to quickly perform positioning of the UE.

[0262] Variation 2 of Embodiment 1 In transmitting and receiving positioning signals between the base station and the UE, the base station and / or the UE may use beams, and the base station and / or the UE may transmit and receive positioning signals by sweeping beams within a range of multiple beams.

[0263] In the above, the following problem occurs: In transmitting and receiving a downlink positioning signal and an uplink positioning signal, the base station and / or the UE sweeps the beam, which takes time for the positioning signal to travel back and forth between the UE and the base station. As a result, the problem of increased latency in positioning occurs.

[0264] In this second modification of the first embodiment, a method for solving the above-mentioned problems will be disclosed.

[0265] The downlink positioning signal setting is associated with the uplink positioning signal setting. The downlink positioning signal may be, for example, a PRS. The uplink positioning signal may be, for example, an SRS.

[0266] The setting association may be, for example, association between the timing of an uplink positioning signal and a downlink positioning signal. The timing may be set, for example, on a frame-by-frame basis, a subframe-by-subframe basis, a slot-by-slot basis, or a symbol-by-symbol basis. For example, the UE may transmit an uplink positioning signal to the base station at a timing associated with the timing of receiving the downlink positioning signal from the base station. The base station may receive the uplink positioning signal from the UE at an uplink positioning signal reception timing associated with the transmission timing of the downlink positioning signal. The UE may transmit the uplink positioning signal using the same beam as used to receive the downlink positioning signal. The base station may receive the uplink positioning signal using the same beam as used to transmit the downlink positioning signal. This allows, for example, the base station to quickly obtain information about the positioning signal received by the UE.

[0267] As another example, the base station may transmit a downlink positioning signal to the UE at a timing associated with the timing of receiving an uplink positioning signal from the UE. The UE may receive the downlink positioning signal from the base station at a downlink positioning signal reception timing associated with the transmission timing of the uplink positioning signal. The base station may transmit the downlink positioning signal using the same beam as used to receive the uplink positioning signal. The UE may receive the downlink positioning signal using the same beam as used to transmit the uplink positioning signal. This allows the UE to quickly obtain information about the positioning signal received by the base station, for example.

[0268] The setting association may be, for example, association of the frequencies of the uplink positioning signal and the downlink positioning signal. The frequency association may be performed, for example, in units of RB or in units of RE. The frequency association may be, for example, such that the frequencies of the uplink positioning signal and the downlink positioning signal are the same, or such that the frequencies of the uplink positioning signal and the downlink positioning signal are shifted by a certain amount. Alternatively, other associations may be used as the frequency association. For example, the UE may transmit the uplink positioning signal to the base station using a frequency resource associated with the frequency resource of the downlink positioning signal from the base station. The base station may perform a receiving operation of the uplink positioning signal using a frequency resource associated with the frequency resource of the downlink positioning signal. The UE may perform a transmitting operation of the uplink positioning signal using the same beam as the beam used to receive the downlink positioning signal. This enables, for example, the base station to quickly acquire information about the positioning signal received by the UE.

[0269] As another example, the base station may transmit a downlink positioning signal to the UE using a frequency resource associated with the frequency resource of the uplink positioning signal from the UE. The UE may receive the downlink positioning signal from the base station using the frequency resource associated with the frequency resource of the uplink positioning signal. The base station may transmit the downlink positioning signal using the same beam as used to receive the uplink positioning signal. The UE may receive the downlink positioning signal using the same beam as used to transmit the uplink positioning signal. This allows the UE to quickly obtain information about the positioning signal received by the base station, for example.

[0270] The setting association may be, for example, a combination of the timing and frequency described above, which may, for example, avoid complexity in the communication system.

[0271] The base station may be a serving base station or a neighboring base station, which may enable, for example, quick transmission and reception of positioning signals between the base station and the UE, including the neighboring base station.

[0272] The base station notifies the UE of information regarding the configuration of the downlink positioning signal and / or the uplink positioning signal. For example, the configuration of the downlink positioning signal may include information regarding the configuration of the corresponding uplink signal.

[0273] The notification may be performed using, for example, LPP Provide Assistance data disclosed in Non-Patent Document 22 (TS38.305), which may reduce signaling between the base station and the UE, for example.

[0274] As another example, the configuration of an uplink positioning signal may include information about the configuration of the corresponding downlink signal. This notification may be performed, for example, using the UE SRS Configuration disclosed in Non-Patent Document 22 (TS38.305). This may reduce, for example, the signaling between the base station and the UE.

[0275] The notification from the serving base station to the UE may include information regarding a correspondence relationship between the settings of the downlink positioning signal and / or the uplink positioning signal in the neighboring base stations. The serving base station may request information regarding the correspondence relationship from the neighboring base stations. The neighboring base stations may notify the serving base station of the information regarding the correspondence relationship.

[0276] New signaling may be provided for use in the notification from the serving base station to the UE, and may be, for example, RRC signaling, MAC signaling, or L1 / L2 signaling, and may include, for example, LPP and / or NRPPa signaling.

[0277] New signaling may be provided for use in the request from the serving base station to the neighboring base stations. The signaling may be, for example, Xn signaling. The Xn signaling may include, for example, LPP and / or NRPPa signaling. As another example, the signaling used for the request may be included in the NRPPa DL PRS CONFIGURATION INFORMATION EXCHANGE procedure disclosed in Non-Patent Document 22 (TS38.305). This allows, for example, the serving base station to quickly send the request to the neighboring base stations.

[0278] New signaling may be provided for use in the notification from a neighboring base station to a serving base station. The signaling may be, for example, Xn signaling. The Xn signaling may include, for example, LPP and / or NRPPa signaling. As another example, the signaling used for the notification may be included in the gNB configuration notification disclosed in the first embodiment. This makes it possible, for example, to reduce the amount of signaling between base stations. As another example, the signaling used for the request may be included in the NRPPa DL PRS CONFIGURATION INFORMATION EXCHANGE procedure disclosed in Non-Patent Document 22 (TS38.305). This makes it possible, for example, for the neighboring base station to quickly transmit the notification to the serving base station.

[0279] In this second modification of the first embodiment, an SS block may be used for the downlink positioning signal, and a PRACH may be used for the uplink positioning signal. The serving base station and / or a neighboring base station may notify or broadcast information related to the time at a predetermined frame timing. The UE may measure a downlink propagation delay time using the notification, broadcast, and / or reception of the SS block. The serving base station and / or a neighboring base station may specify a PRACH transmission timing from the UE. The specification may be notified to the UE from the serving base station, or may be broadcast to the UE from the serving base station and / or a neighboring base station. The neighboring base station may notify the serving base station of information related to the specification. The serving base station and / or a neighboring base station may measure an uplink propagation delay time using the specification information and / or PRACH reception from the UE. This, for example, makes it possible to avoid complexity in the communication system.

[0280] The method disclosed in this second modification of the first embodiment may be applied to the case where the base station has an LMF, which makes it possible to reduce the positioning time, for example.

[0281] The method disclosed in this second modification of the first embodiment may be applied to a case where the UE has an LMF, which makes it possible to reduce the time from the start of positioning to the start of use of the positioning information by the UE, for example.

[0282] This modification 2 of the first embodiment makes it possible to shorten the time required for beam sweeping in positioning, thereby shortening the positioning time. Also, it makes it possible to reduce the number of symbols required for the positioning signal, thereby improving the communication rate.

[0283] Embodiment 2 In Multi-RTT, the location calculation may be performed by the UE, and the serving base station may notify the UE of information regarding the reception result of the positioning signal.

[0284] The above-mentioned problem arises as follows: The sequence for when the UE performs the position calculation is not disclosed. As a result, a problem occurs in that a positioning method in which the UE performs the position calculation cannot be realized.

[0285] In the second embodiment, a method for solving the above-mentioned problem will be disclosed.

[0286] The LMF notifies the UE of information about the location of the base station. The location information may be expressed in absolute coordinates such as latitude, longitude, and altitude, or in relative coordinates based on a predetermined point. The base station may be a serving base station or a neighboring base station.

[0287] The information about the location of the base station may include information about accuracy. The information about accuracy may be, for example, information about the accuracy of the location of the base station. The UE may use the information about accuracy to derive the accuracy of its own UE's location calculation. This allows, for example, the UE to more accurately derive the accuracy of its own UE's location calculation.

[0288] The notification from the LMF to the UE may include information about the transmission and reception results of the positioning signal. As another example, the notification from the LMF to the UE of information about the location of the base station and information about the transmission and reception results of the positioning signal may be performed at different times.

[0289] The following items (1) to (7) are disclosed as information relating to the results of transmission and reception of the positioning signal.

[0290] (1) Information regarding the time of reception of the upstream positioning signal.

[0291] (2) Information regarding the time of transmission of the downlink positioning signal.

[0292] (3) Information regarding the correspondence between downstream positioning signals and upstream positioning signals.

[0293] (4) Information regarding the reception quality of the uplink positioning signal.

[0294] (5) Information used to identify a base station, cell, DU, and / or TRP.

[0295] (6) Information regarding the accuracy of reception results.

[0296] (7) A combination of (1) to (6) above.

[0297] The information regarding (1) above may be information regarding the time when the base station receives the uplink positioning signal. As another example, the information regarding (1) above may be the difference between the time when the UE transmits the uplink positioning signal and the time when the base station receives the uplink positioning signal. The UE may derive the propagation delay of the uplink positioning signal using the information regarding (1) above. This allows the UE to calculate its own position using the uplink positioning signal, for example.

[0298] The information regarding (2) above may be information regarding the time when the base station transmits the downlink positioning signal. The UE may derive the propagation delay of the downlink positioning signal using the information regarding (2) above. This allows the UE to calculate its own position using the uplink positioning signal, for example.

[0299] The information regarding (3) above may be, for example, the information disclosed in Modification 2 of Embodiment 1. The UE may use this information to obtain information regarding the uplink positioning signal received by the base station. This allows the UE to avoid, for example, the complexity of calculating the round-trip propagation delay.

[0300] The information regarding (4) above may be, for example, information regarding the RSRP of the uplink positioning signal, information regarding the RSRQ, or information regarding the SINR. The UE may use this information to determine downlink measurement signal information to be used in calculating the location of the UE. This allows the UE to calculate the location of the UE using, for example, high-quality positioning signal measurement results. As a result, the accuracy of the location calculation of the UE can be improved.

[0301] The information related to (5) above may be, for example, the identifiers of the base station, the cell, the DU, and / or the TRP, which allows, for example, the UE to quickly identify the base station related to the reception result.

[0302] The information related to (6) above may be, for example, time accuracy. The UE may use the information to calculate its own location. This allows the UE to derive the accuracy of its own location calculation, for example.

[0303] As an example of the above (7), the identifier disclosed in the above (5) may be used in combination with the information related to the above (1) to (4) and / or (6). One or more such combinations may be provided. The multiple combinations may be, for example, a list that associates identifiers of base stations, cells, DUs, and / or TRPs with transmission and reception results. This enables, for example, the UE to quickly process information related to the transmission and reception results of the positioning signal and improve the accuracy of the positioning results.

[0304] The UE may use a predetermined number of uplink positioning signal reception results in order of the reception quality of the uplink positioning signal to calculate the position of the UE itself. This allows the UE to calculate the position of the UE itself using, for example, high-quality positioning signal measurement results. As a result, the accuracy of the position calculation of the UE itself can be improved.

[0305] The predetermined number may be determined by a standard, or may be determined by a base station and notified to a UE, or may be determined by an AMF and notified to a UE via a serving base station, or may be determined by an LMF and notified to a UE via a serving base station.

[0306] As another example, the UE may use only the uplink positioning signal reception results for which the reception quality of the uplink positioning signal is equal to or higher than a predetermined threshold for calculating the position of the UE itself. This can achieve, for example, the same effects as those described above.

[0307] The predetermined threshold may be determined by a standard, or may be determined by a base station and notified to the UE, or may be determined by an AMF and notified to the UE via a serving base station, or may be determined by an LMF and notified to the UE via a serving base station.

[0308] As another example, the UE may use a predetermined number of uplink positioning signal reception results, in descending order of reception quality, of the measurement results in which the reception quality of the uplink positioning signal is equal to or higher than a predetermined threshold, for calculating the position of the UE itself. This allows the UE to calculate the position of the UE itself using measurement results of positioning signals with higher quality, for example. As a result, the accuracy of the position calculation of the UE itself can be further improved.

[0309] As another example, the UE may use the reception quality of the downlink positioning signal. The UE may acquire the reception quality of the downlink positioning signal from the reception result of the downlink positioning signal at the UE itself. The UE may use a combination of the reception quality of the uplink positioning signal and the reception quality of the downlink positioning signal. This allows the UE to calculate the location of the UE itself using, for example, high-quality measurement results for both uplink and downlink. As a result, the accuracy of the location calculation of the UE itself using Multi-RTT can be improved.

[0310] The combination of the reception quality of the uplink positioning signal and the reception quality of the downlink positioning signal may be, for example, the sum of the reception quality of the uplink positioning signal (e.g., RSRQ, RSRP, SINR) and the reception quality of the downlink positioning signal (e.g., RSRQ, RSRP, SINR). The value of the sum may be a value calculated using true values, or may be a value calculated using logarithmic values ​​(e.g., decibel values). For example, by using a value calculated using logarithmic values, the influence of the value of the worse quality of the uplink positioning signal or the downlink positioning signal becomes greater, thereby making it possible to use measurement results in which the reception quality of both the uplink and downlink positioning signals is ensured. As a result, it is possible to improve the accuracy of the position calculation of the UE using Multi-RTT.

[0311] As another example of a combination of the reception quality of the uplink positioning signal and the reception quality of the downlink positioning signal, the worse of the reception quality of the uplink positioning signal and the reception quality of the downlink positioning signal may be used. This allows, for example, measurement results that ensure the reception quality of both the uplink and downlink positioning signals to be used. As a result, it is possible to improve the accuracy of the location calculation of the UE using Multi-RTT.

[0312] As an example of using a combination of the reception quality of the uplink positioning signal and the reception quality of the downlink positioning signal, the UE may use the results of a predetermined number of combinations in order of the best combinations for calculating the position of the UE itself. This allows the UE to calculate the position of the UE itself using, for example, high-quality positioning signal measurement results. As a result, the accuracy of the position calculation of the UE itself can be improved.

[0313] The predetermined number may be determined by a standard, or may be determined by a base station and notified to a UE, or may be determined by an AMF and notified to a UE via a serving base station, or may be determined by an LMF and notified to a UE via a serving base station.

[0314] As another example, the UE may use only the uplink positioning signal reception results for which the reception quality of the combination is equal to or greater than a predetermined threshold for calculating the position of the UE itself. This can achieve, for example, the same effects as those described above.

[0315] The predetermined threshold may be determined by a standard, or may be determined by a base station and notified to the UE, or may be determined by an AMF and notified to the UE via a serving base station, or may be determined by an LMF and notified to the UE via a serving base station.

[0316] As another example, the UE may use a predetermined number of combinations of reception qualities in order of best reception quality from among the measurement results in which the reception quality of the combination is equal to or greater than a predetermined threshold for calculating the position of the UE itself. This allows the UE to calculate the position of the UE itself using measurement results of positioning signals with higher quality. As a result, the accuracy of the calculation of the position of the UE itself can be further improved.

[0317] When there are multiple measurement results using the same beam for the UE itself, the UE may use the measurement result with the best reception quality of the uplink and / or downlink positioning signal for calculating the position of the UE itself. This operation may be performed, for example, when the number of beams the UE has is greater than or equal to a predetermined number. Alternatively, this operation may be performed, for example, when the number of the UE itself included in the multiple measurement results for the UE is greater than or equal to a predetermined number. This allows the UE to use measurement results from various directions for calculating the position of the UE itself. As a result, the accuracy of positioning can be improved.

[0318] The LMF may notify the UE of information regarding the location of the base station before starting transmission and reception of a positioning signal. For example, the LMF may include the notification in a notification of information used for positioning (e.g., LPP Provide Assistance Data disclosed in Non-Patent Document 22 (TS38.305 V16.0.0)) and notify the UE. Alternatively, for example, the LMF may include the notification in a positioning request (e.g., LPP Request Location Information disclosed in Non-Patent Document 22 (TS38.305 V16.0.0)) and notify the UE. This allows, for example, the UE to quickly obtain the information, and as a result, to quickly perform processing related to positioning.

[0319] As another example, the LMF may notify the UE of information regarding the base station's location after completing transmission and reception of the positioning signal. For example, the LMF may notify the UE of the information by including it in a notification of the reception result of the positioning signal by the serving base station and / or surrounding base stations. When the base station is moving, the LMF may notify the UE of information regarding the base station's location after completing transmission and reception of the positioning signal. This makes it easier to ensure, for example, temporal consistency between the base station's location and the reception result of the positioning signal. As a result, it is possible to prevent deterioration of positioning accuracy.

[0320] The LMF may transmit information about the location of the base station to the UE using LPP signaling or NRPPa signaling, which may reduce complexity in the design of the communication system, for example.

[0321] As another example, the notification may be performed using NAS signaling, which may be used, for example, when the LMF is located in the CN, thereby avoiding complexity in the design of the communication system.

[0322] As another example, the notification may be performed using RRC signaling, for example, when the LMF is present in the serving base station, which may reduce complexity in the design of the communication system.

[0323] As another example, the notification may be performed using MAC signaling, for example, when an LMF is present in the serving base station, which allows the base station to quickly notify the notification.

[0324] As another example, the notification may be performed using L1 / L2 signaling, which may be used, for example, when an LMF is present in the serving base station, allowing the base station to notify the notification more quickly.

[0325] The procedure up to receiving the positioning signal may be the same as the procedure disclosed in embodiment 1. This makes it possible to avoid, for example, complexity in the communication system.

[0326] The UE may notify the LMF of its location information, which may allow the LMF to smoothly perform location control of subordinate devices, for example.

[0327] Figures 28 and 29 are sequence diagrams showing the operation of a UE when calculating its position in Multi-RTT. Figures 28 and 29 are connected at the position of boundary line BL2829. In Figures 28 and 29, the same steps as in Figures 14 to 19 are assigned the same step numbers, and common explanations will be omitted.

[0328] Steps ST1401 to ST1413 shown in FIG. 28 are the same as those in FIG.

[0329] Step ST1415 shown in FIG. 28 is the same as that in FIG.

[0330] In step ST1419 shown in FIG. 28, the LMF notifies the UE of information used for positioning.

[0331] Step ST1421 shown in FIG. 28 is the same as that in FIG.

[0332] Steps ST1623 and ST1625 shown in FIG. 28 are the same as those in FIG.

[0333] Steps ST1422 to ST1425 shown in FIG. 29 are the same as those in FIG.

[0334] In Step ST3027 shown in FIG. 29, the LMF notifies the UE of information related to the positioning signal reception results of the serving base station and / or neighboring base stations. For example, LPP signaling may be used for this notification. For example, the LPP signaling may be the LPP Provide Location Information disclosed in Non-Patent Document 22 (TS38.305 V16.0.0). Alternatively, new LPP signaling may be provided. In Step ST3029, the UE calculates the location of its own UE.

[0335] In step ST3031 shown in Fig. 29, the UE notifies the LMF of information relating to the location of the UE itself. This information may be, for example, the calculation result in step ST3029. This enables the LMF to smoothly control the locations of devices under its control, for example.

[0336] Steps ST1434 and ST1435 shown in FIG. 29 are the same as those in FIG.

[0337] The notification of the positioning result from the neighboring base station may not be performed via the LMF. For example, the neighboring base station may notify the serving base station of the positioning result. The serving base station may notify the UE of the positioning result. This may reduce the amount of signaling between the base station and the LMF, for example.

[0338] As an example in which the notification of the positioning result from the neighboring base station is not performed via the LMF, the information notified in Step ST1425 shown in FIG. 29 may be notified from the neighboring base station to the serving base station. The information notified in Step ST3027 shown in FIG. 29 may be notified from the serving base station to the UE. The information notified from the serving base station to the UE in Step ST3027 may include the information notified from the neighboring base station to the serving base station in Step ST1425. This makes it possible to reduce, for example, the amount of signaling between the base station and the LMF.

[0339] Another solution will be disclosed. The base station may notify the UE of information about the location of the base station. The notification may include information about the transmission and reception results of the positioning signal. The information about the reception results of the positioning signal that the base station notifies the UE of may include the above-mentioned (1) to (5) disclosed as the information about the transmission and reception results of the positioning signal that the LMF notifies the UE of.

[0340] The notification of the above information from the neighboring base station to the UE may be performed via the serving base station. The neighboring base station may notify the serving base station of the above information. The notification may be performed using an inter-base station interface, for example, an Xn interface. The serving base station may include the information notified from the neighboring base station in the notification to the UE. The UE may obtain the information from the serving base station and the neighboring base station using the notification. This makes it possible, for example, to quickly notify the UE of the information from the serving base station and / or the neighboring base station.

[0341] The method disclosed in the second embodiment may be applied when the base station has an LMF.

[0342] Figures 30 and 31 are sequence diagrams showing the operation of a UE calculating its position in Multi-RTT when the base station has an LMF. Figures 30 and 31 are connected at the position of boundary line BL3031. In Figures 30 and 31, the same steps as in Figures 28 and 29 are assigned the same step numbers, and common explanations will be omitted.

[0343] Steps ST1601 and ST1403 shown in FIG. 30 are the same as those in FIG.

[0344] Steps ST1407 to ST1413 shown in FIG. 30 are the same as those in FIG.

[0345] Step ST1615 shown in FIG. 30 is the same as that in FIG.

[0346] Steps ST1619 to ST1625 shown in FIG. 30 are the same as those in FIG.

[0347] Steps ST1422 and ST1423 shown in FIG. 31 are the same as those in FIG.

[0348] Step ST1627 shown in FIG. 31 is the same as that in FIG.

[0349] In Step ST3129 shown in FIG. 31 , the serving base station notifies the UE of information related to the positioning signal reception results at its own base station and / or neighboring base stations. For this notification, for example, LPP signaling may be used. For example, the LPP signaling may be the LPP Provide Location Information disclosed in Non-Patent Document 22 (TS38.305 V16.0.0), or new LPP signaling may be provided. In Step ST3029, the UE calculates the location of its own UE.

[0350] In Step ST3133 shown in FIG. 31 , the UE notifies the serving base station of information related to the location of the UE itself. This information may be, for example, the calculation result in Step ST3029. This enables, for example, the LMF of the serving base station to smoothly control the locations of devices under its control.

[0351] Steps ST1434 and ST1435 shown in FIG. 31 are the same as those in FIG.

[0352] The method disclosed in the second embodiment may be applied to the case where the UE has an LMF. The sequence showing the operation of the UE to calculate the location of the UE in Multi-RTT when the UE has an LMF may be the same as that shown in Figures 22 and 23.

[0353] In a communication system, multiple devices may have the LMF function. The device may be, for example, a UE, a base station, or a device in a core network. The function may be shared among the LMFs of multiple devices. For example, the LMF of a UE may perform position calculation, and the LMF of a device in the core network may manage the position calculation results (e.g., respond to positioning result inquiries from other devices). This may reduce delays related to positioning in the communication system, for example.

[0354] When multiple devices have the LMF function, for example, the LMF of the UE may take on part of the function of the LMF of the base station. For example, the LMF of the UE may perform the position calculation of the UE itself. This can achieve the same effect as described above.

[0355] When multiple devices have the LMF function, one LMF (hereinafter, sometimes referred to as LMF1) may inquire about the location information of the UE from the other LMF (hereinafter, sometimes referred to as LMF2). LMF1 may be, for example, an LMF provided in a base station and / or a core network. LMF2 may be, for example, an LMF provided in the UE. LMF2 may notify LMF1 of the location information. For example, LPP signaling or NRPPa signaling may be used for the inquiry and / or the notification of the location information. This makes it possible to avoid, for example, complexity in signaling between multiple LMFs.

[0356] The method disclosed in the first embodiment may be applied to the second embodiment. For example, the base station may instruct the UE to set a measurement gap without waiting for a measurement gap setting request from the UE. This may further reduce the latency of positioning, for example.

[0357] The method disclosed in Variation 1 of Embodiment 1 may be applied to Embodiment 2. For example, the serving base station may notify surrounding base stations of information regarding the beam used for communication with the UE. This makes it possible to further reduce the latency of positioning, for example.

[0358] The method disclosed in the second modification of the first embodiment may be applied to the second embodiment. For example, a correspondence relationship may be set between the downlink positioning signal and the uplink positioning signal. This makes it possible to further reduce the latency of positioning, for example.

[0359] According to the second embodiment, it is possible to reduce latency in positioning in which the UE calculates its position.

[0360] Embodiment 3 The procedure for handling conflicts between the positioning procedure and other processes is not defined, which may result in malfunctions between the UE and the base station.

[0361] In the third embodiment, a method for solving the above-mentioned problem will be disclosed.

[0362] Priorities (hereinafter sometimes referred to as positioning priorities) are assigned to positioning procedures.

[0363] The positioning priority may be associated with the value of the ToS field of the IP header (see Non-Patent Document 26 (IETF RFC791)). The IP header may be an IPv4 header or an IPv6 header. For example, a positioning procedure assigned a positioning priority higher than the value of the ToS field may be given higher priority than the transmission and reception of the IP packet.

[0364] As another example, the positioning priority may be associated with a priority assigned to each logical channel (see Non-Patent Document 27 (TS38.331)). For example, a positioning procedure assigned a positioning priority lower than the Priority value may be given higher priority than the transmission and reception of transport data on that logical channel. This, for example, makes it possible to avoid complex scheduling during the execution of the positioning procedure.

[0365] As another example, the positioning priority may be associated with a priority level (Priority Level) assigned to each QoS flow (see Non-Patent Document 20 (TS23.501), Section 5.7.3.3). For example, a positioning procedure assigned a positioning priority lower than the Priority Level value may be given higher priority than the transmission and reception of packets of the QoS flow. This, for example, makes it possible to avoid complexity in packet transmission and reception during the execution of the positioning procedure.

[0366] As another example, the positioning priority may be fixed among other processes, for example, the priority may be fixed in a standard, which may avoid complexity in the communication system.

[0367] The positioning priority values ​​may be statically defined in a standard, which may, for example, avoid complexity in the communication system.

[0368] As another example, the value of the positioning priority may be determined semi-statically or dynamically.

[0369] For example, the PCF may determine the positioning priority value. This makes it possible to uniformly perform priority control within the communication system, for example. As a result, it is possible to prevent malfunction of devices within the communication system. The PCF may notify the base station of the determined priority value. The notification may be performed via the AMF and / or the LMF. The base station may notify the UE of the priority value. As another example, the AMF may notify the UE of the priority value directly, for example, by using NAS signaling. As another example, the LMF may notify the UE of the priority value directly, for example, by using LPP and / or NRPPa signaling.

[0370] As another example, the SMF may determine the positioning priority value. The SMF may determine the positioning priority using information about the priorities of other QoS flows. This may, for example, reduce the amount of processing required for determining the positioning priority. The SMF may notify the base station of the determined priority value. The notification may be performed via the AMF and / or the LMF. The base station may notify the UE of the priority value. As another example, the AMF may notify the UE of the priority value directly, for example, using NAS signaling. As another example, the LMF may notify the UE of the priority value directly, for example, using LPP and / or NRPPa signaling.

[0371] As another example, the AMF may determine the positioning priority value. The AMF may determine the positioning priority using, for example, information about the network load. This makes it possible to prevent network congestion due to positioning, for example. The AMF may notify the base station of the determined priority value. The base station may notify the UE of the priority value. As another example, the AMF may notify the UE of the priority value directly, for example, by using NAS signaling. As another example, the AMF may notify the LMF of the priority value. The LMF may notify the UE of the priority value via the base station, or may notify the UE directly, for example, by using LPP and / or NRPPa signaling.

[0372] As another example, the LMF may determine the value of the positioning priority. This allows, for example, a communication system to flexibly determine the positioning priority according to the requirements for positioning. The LMF may notify the priority value to the AMF or to the base station. The base station may notify the priority to the UE. The LMF may notify the priority to the UE. The notification from the LMF to the UE may be performed via the base station or directly, for example, using LPP and / or NRPPa signaling.

[0373] As another example, the UE may determine the value of the positioning priority. The UE may notify the determined value to the base station, the AMF, or the LMF. This enables flexible priority control according to the status of the UE to be positioned, for example.

[0374] As another example, the UE may request a base station, an AMF, or an LMF to determine a positioning priority value. The request may include information about the priority value requested by the UE. The base station, the AMF, and / or the LMF may use the request to determine a positioning priority value. The base station, the AMF, and / or the LMF may notify the UE of the determined priority value. This may, for example, achieve the same effect as described above.

[0375] The UE may prioritize transmission and reception of data with a higher priority than the positioning priority over transmission and reception of the positioning signal. For example, the UE may not receive the downlink positioning signal at a timing that overlaps with transmission and reception of data with a higher priority than the positioning priority (hereinafter, sometimes referred to as high-priority data). The UE may resume reception of the downlink positioning signal after completing transmission and reception of the high-priority data.

[0376] Preemption may be used in the transmission and reception of high-priority data in a UE. For example, the UE may transmit and receive high-priority data when it receives a preemption notification from a base station. This may, for example, reduce complexity in the communication system.

[0377] As another example, the UE may receive the downlink positioning signal at a timing that overlaps with the transmission and reception of the high-priority data. For example, if the UE has multiple beams, it may receive the high-priority data and the downlink positioning signal simultaneously. As another example, if the UE has multiple transceivers, it may transmit the high-priority data and receive the downlink positioning signal simultaneously.

[0378] As another example, the UE may not transmit an uplink positioning signal at a timing that overlaps with transmission and reception of data with a priority higher than the positioning priority (hereinafter, sometimes referred to as high-priority data). The UE may resume transmission of the uplink positioning signal after completing transmission and reception of the high-priority data. The UE may not retransmit the uplink positioning signal that could not be transmitted at the overlapping timing after completing transmission and reception of the high-priority data. For example, the UE may transmit the uplink positioning signal at the next transmission timing assigned to the uplink positioning signal. This, for example, makes it possible to avoid complexity in the communication system. As another example, the UE may retransmit the uplink positioning signal that could not be transmitted at the overlapping timing after completing transmission and reception of the high-priority data. This, for example, makes it possible for the UE to quickly transmit the uplink positioning signal.

[0379] As another example, the UE may transmit an uplink positioning signal at a timing that overlaps with the transmission and reception of high priority data. For example, when the UE has multiple beams, the UE may transmit high priority data and the uplink positioning signal simultaneously. As another example, when the UE has multiple transceivers, the UE may receive and / or transmit high priority data and the uplink positioning signal simultaneously.

[0380] The UE may reduce the transmission power of the uplink positioning signal when the transmission and reception of the high-priority data overlap, which may reduce interference from the UE, for example.

[0381] As another example, the UE may stop transmission power when transmitting an uplink positioning signal at a timing that overlaps with transmission and reception of high-priority data, which may make it possible to avoid, for example, complexity in transmission control in the UE.

[0382] The above method may also be applied when high priority data is transmitted and received using semi-persistent scheduling, which may, for example, reduce the complexity of the transmission and reception process in the UE.

[0383] The timing (e.g., period and offset for the period) of semi-persistent scheduling used for transmitting and receiving high priority data may be configured so as not to overlap with the timing (e.g., period and offset for the period) of transmitting and receiving positioning signals. The UE may expect that the timing (e.g., period and offset for the period) of semi-persistent scheduling used for transmitting and receiving high priority data will not overlap with the timing (e.g., period and offset for the period) of transmitting and receiving positioning signals. This, for example, can prevent the UE from being unable to transmit and receive positioning signals due to overlap between the timing of semi-persistent scheduling and the timing of transmitting and receiving positioning signals.

[0384] The above method may also be applied when high priority data is transmitted and received using a configured grant, which may, for example, avoid complexity in the transmission and reception process in the UE.

[0385] The timing (e.g., period and offset for the period) of the configured grant used for transmitting and receiving high priority data may be configured so as not to overlap with the timing (e.g., period and offset for the period) of transmitting and receiving positioning signals. The UE may expect that the timing (e.g., period and offset for the period) of the configured grant used for transmitting and receiving high priority data will not overlap with the timing (e.g., period and offset for the period) of transmitting and receiving positioning signals. This may, for example, prevent the UE from being unable to transmit or receive positioning signals due to an overlap between the timing of the configured grant and the timing of transmitting or receiving positioning signals.

[0386] The above method may also be applied when the timing of data transmission / reception using dynamic scheduling overlaps with the timing of transmission / reception of positioning signals. For example, data transmission / reception using dynamic scheduling may be given a higher priority than the transmission / reception of positioning signals. This may, for example, reduce the complexity of UE processing.

[0387] The UE may not transmit or receive data with a priority lower than the positioning priority (hereinafter, sometimes referred to as low-priority data). The UE may prioritize transmission and reception of positioning signals over transmission and reception of low-priority data. For example, the UE may receive a downlink positioning signal at a timing that overlaps with transmission and reception of low-priority data. The UE may transmit or receive low-priority data after completing reception of the downlink positioning signal. As another example, the UE may transmit an uplink positioning signal at a timing that overlaps with transmission and reception of low-priority data. The UE may transmit or receive low-priority data after completing reception of the uplink positioning signal.

[0388] Retransmission may be used to receive the low-priority data that could not be received in the above-described manner. The retransmission may be, for example, HARQ retransmission. For example, the UE may receive the low-priority downlink data that could not be received by HARQ retransmission. The UE may not send a HARQ response to the downlink data that could not be received. The base station may use the absence of a HARQ response from the UE to send a HARQ retransmission to the UE. This may, for example, avoid the complexity of receiving low-priority data.

[0389] Retransmission may be used to transmit the low-priority data that could not be transmitted in the above-described manner. The retransmission may be, for example, HARQ retransmission. For example, the UE may transmit the low-priority uplink data that could not be transmitted by HARQ retransmission. The base station may notify the UE of an uplink grant for retransmitting the uplink data that the UE could not transmit. The UE may use the grant to retransmit the uplink data that could not be transmitted. This may, for example, avoid complexity in transmitting low-priority data.

[0390] As another example, the UE may perform transmission and reception of low priority data at a timing that overlaps with reception of the downlink positioning signal. For example, when the UE has multiple beams, it may simultaneously perform reception of the downlink positioning signal and transmission and reception of the low priority data. As another example, when the UE has multiple transceivers, it may simultaneously perform reception of the downlink positioning signal and transmission and reception of the low priority data. This, for example, can improve the efficiency of the communication system.

[0391] As another example, the UE may transmit and receive low-priority data at a timing that overlaps with the transmission of the uplink positioning signal. For example, when the UE has multiple beams, the UE may transmit the uplink positioning signal and transmit and receive low-priority data simultaneously. As another example, when the UE has multiple transceivers, the UE may transmit the uplink positioning signal and transmit and receive low-priority data simultaneously. This, for example, can improve the efficiency of the communication system.

[0392] The UE may transmit low-priority data at a timing that overlaps with the transmission of the uplink positioning signal, with reduced transmission power, which can reduce interference from the UE at the base station, for example.

[0393] As another example, the UE may stop transmission power when transmitting low-priority data at a timing that overlaps with the transmission of the uplink positioning signal, which may, for example, avoid complexity in transmission control in the UE.

[0394] The above method may also be applied when semi-persistent scheduling is used to transmit and receive low priority data, which may, for example, reduce the complexity of the transmission and reception process in the UE.

[0395] The timing (e.g., period and offset for the period) of semi-persistent scheduling used for transmitting and receiving low priority data may be configured so as not to overlap with the timing (e.g., period and offset for the period) of transmitting and receiving positioning signals. The UE may expect that the timing (e.g., period and offset for the period) of semi-persistent scheduling used for transmitting and receiving low priority data will not overlap with the timing (e.g., period and offset for the period) of transmitting and receiving positioning signals. This, for example, can prevent the UE from being unable to transmit and receive low priority data due to overlap between the timing of semi-persistent scheduling and the timing of transmitting and receiving positioning signals.

[0396] The above method may also be applied when low priority data is transmitted and received using a configured grant, which may, for example, avoid complexity in the transmission and reception process in the UE.

[0397] The timing (e.g., period and offset for the period) of the configured grant used for transmitting and receiving low priority data may be configured so as not to overlap with the timing (e.g., period and offset for the period) of transmitting and receiving positioning signals. The UE may expect that the timing (e.g., period and offset for the period) of the configured grant used for transmitting and receiving low priority data will not overlap with the timing (e.g., period and offset for the period) of transmitting and receiving positioning signals. This may, for example, prevent the UE from being unable to transmit and receive low priority data due to an overlap between the configured grant and the timing of transmitting and receiving positioning signals.

[0398] The serving base station may acquire information about semi-persistent scheduling and / or configured grants of the neighboring base stations from the neighboring base stations. The semi-persistent scheduling and / or configured grants of the neighboring base stations may be used for transmission and reception with other UEs. This makes it possible to prevent, for example, transmission and reception of positioning signals with the UE from being interrupted by the semi-persistent scheduling and / or configured grants of the neighboring base stations.

[0399] The serving base station may request information about semi-persistent scheduling and / or configured grants from neighboring base stations. The request may be made via the LMF or directly from the serving base station to the neighboring base stations. For example, the serving base station may make the request over the base station-to-base station interface.

[0400] The neighboring base station may notify the serving base station of information regarding the semi-persistent scheduling and / or configured grants at the base station. The notification may be made via the LMF or directly from the neighboring base station to the serving base station. For example, the serving base station may make the request over the base station-to-base station interface.

[0401] The following (1) to (5) are disclosed as examples of information regarding semi-persistent scheduling and / or configured grants in neighboring base stations.

[0402] (1) Information regarding the direction of transmission.

[0403] (2) Information regarding semi-persistent scheduling and / or established grant types.

[0404] (3) Information regarding the timing of allocation.

[0405] (4) Information regarding communication priority.

[0406] (5) A combination of (1) to (4) above.

[0407] The information related to (1) above may be, for example, information indicating uplink or downlink. Using the information related to (1) above, the serving base station may, for example, configure the UE to stop transmitting uplink positioning signals at the timing of downlink transmission at a neighboring base station. This makes it possible to prevent interference with other UEs that communicate with the neighboring base station.

[0408] The information regarding (2) above may be information regarding the distinction between semi-persistent scheduling and configured grants. The base station may use the information regarding the distinction to determine whether uplink or downlink communication is being performed in the neighboring base station. This may provide, for example, the same effect as described above.

[0409] As another example, the information related to (2) above may include information about the type of configured grant. For example, the information may be the type disclosed in Section 5.3.1 of Non-Patent Document 16 (TS38.300). The serving base station may use the information to determine whether to transmit or receive a UE positioning signal. For example, when the configured grant is configured using only RRC signaling, the serving base station may be configured not to transmit or receive a UE positioning signal. Furthermore, when the configured grant is configured using RRC signaling and DCI, the serving base station may be configured to transmit or receive a UE positioning signal. This may improve, for example, the efficiency of transmission and reception in a communication system.

[0410] The information regarding (3) above may include information regarding the period of semi-persistent scheduling and / or configured grants of neighboring base stations. The information regarding (3) above may include information regarding an offset to the period, i.e., information regarding allocation timing within a certain period. The information regarding (3) above may include information regarding the length allocated to transmitting and receiving positioning signals, such as the number of subframes, the number of slots, and / or the symbol length. The information regarding (3) above may be a combination of multiple of the above. The serving base station may use this information to determine the timing of transmitting and receiving positioning signals in the UE. This may, for example, allow the timing of transmitting and receiving positioning signals to avoid the timing of semi-persistent scheduling and / or configured grants of neighboring base stations.

[0411] The information regarding (4) above may be, for example, information regarding the highest priority of communications that can be transmitted and received in the semi-persistent scheduling and / or configured grants of the neighboring base station.The serving base station may use the information regarding (4) above to configure the UE not to transmit and receive positioning signals for positioning with a positioning priority lower than the semi-persistent scheduling and / or configured grants of the neighboring base station.This makes it possible to prevent interruptions of high-priority communications with the neighboring base station, for example.

[0412] The method disclosed in the third embodiment may be applied to positioning in which the UE calculates the position, i.e., UE-based positioning. This makes it possible to reduce the latency in UE-based positioning while ensuring the latency of high-priority communications, for example.

[0413] The method disclosed in the third embodiment may be applied to positioning in which the LMF performs the position calculation, i.e., UE-assisted positioning. This makes it possible to reduce the latency in UE-assisted positioning while ensuring the latency of high-priority communications, for example.

[0414] Different positioning priorities may be assigned between UE-based positioning and UE-assisted positioning. For example, UE-based positioning may be assigned a higher priority than UE-assisted positioning. This may enable, for example, UE-based positioning to be performed quickly in a communication system, thereby reducing latency in UE-based positioning.

[0415] According to the third embodiment, it is possible to prevent inconsistencies in operations relating to the positioning procedure between the base station and the UE, thereby improving the robustness of the communication system.

[0416] Embodiment 4 A UE in DRX (Discontinuous Reception) may not transmit or receive positioning signals. As another example, a UE in DRX may transmit or receive positioning signals. The UE may transmit or receive positioning signals during an active time of DRX.

[0417] However, no method has been disclosed for meeting the same requirements during DRX as when DRX is not in effect, which causes a problem that the requirements for positioning cannot be met during DRX.

[0418] In the fourth embodiment, a method for solving the above-mentioned problems will be disclosed.

[0419] Time and / or frequency resources for positioning are designated in advance. The resources may include a period outside the active time of DRX. The UE may transmit and receive positioning signals even during the period outside the active time of DRX.

[0420] The resources may be in a narrower frequency range than during normal communication, which can, for example, reduce the power consumption of the UE.

[0421] For example, time and / or frequency resources for positioning (hereinafter, may be referred to as positioning resources) may be configured in advance, and the configuration may be performed in the same manner as for a configured grant, for example.

[0422] The positioning resources may be configured by the LMF. The LMF may request information on DRX configuration from the serving base station. The serving base station may notify the LMF of the information. The LMF may use the information to determine the positioning resources. For example, the LMF may configure the positioning resources so that they are included in the DRX active time (or On duration time) configured by the serving base station. This makes it possible to prevent, for example, an increase in power consumption in the UE.

[0423] The LMF may notify the serving base station, neighboring base stations, or UE of the determined positioning resource configuration. The LMF may notify the UE of the configuration via the serving base station. The LMF may notify the neighboring base stations directly or via the serving base station. The serving base station may notify the UE of the configuration via RRC signaling, MAC signaling, or L1 / L2 signaling. Alternatively, the serving base station may notify the UE of the configuration by directly transferring NAS signaling to the UE, or by directly transferring LPP and / or NRPPa signaling to the UE.

[0424] The UE, the serving base station, and / or the surrounding base stations use the resources to transmit and receive positioning signals.

[0425] Semi-persistent scheduling and / or configured grants for transmitting and receiving positioning results may be provided, and may be transmitted outside of DRX active times, which may allow for, for example, fast positioning while reducing power consumption.

[0426] Whether or not a UE can transmit or receive data outside the DRX active period may be configurable, which, for example, enables flexible operation of a communication system.

[0427] The setting may be performed by a base station. The base station may notify the UE of the setting. For example, RRC signaling may be used to notify the setting. This allows, for example, the base station to transmit more information to the UE. As another example, MAC signaling may be used to notify the setting. This allows, for example, the base station to quickly transmit the information to the UE. As another example, L1 / L2 signaling may be used to notify the setting. This allows, for example, the base station to more quickly transmit the information to the UE.

[0428] The base station may notify the LMF of the configuration. The notification from the base station to the LMF may be, for example, via an inter-base station interface or via an interface between the LMF and the base station. The notification may be, for example, via LPP and / or NRPPa signaling. The LMF may use the information to estimate the positioning latency of the UE. This may, for example, enable efficient positioning operation in the communication system.

[0429] As another example, the setting may be performed by the UE. The UE may perform the setting using, for example, the remaining battery level of the UE itself. For example, the UE may disable transmission and reception of positioning signals outside the DRX active time when the remaining battery level is lower than a predetermined threshold. When the remaining battery level is equal to or greater than the predetermined threshold, the UE may enable transmission and reception of positioning signals outside the DRX active time. This enables flexible positioning control according to, for example, the status of the UE (for example, the remaining battery level).

[0430] The UE may notify the base station of the setting. For example, RRC signaling may be used for the setting from the UE to the base station. This allows, for example, the UE to transmit a large amount of information to the base station. As another example, MAC signaling may be used for the notification of the setting. This allows, for example, the UE to transmit the information to the base station quickly. As another example, L1 / L2 signaling may be used for the notification of the setting. This allows, for example, the UE to transmit the information to the base station even more quickly. The base station may notify the LMF of the setting. The notification of the setting from the base station to the LMF may be performed in the same manner as described above.

[0431] As another example, the setting may be performed by the LMF. The LMF may determine the setting using, for example, the positioning priority of each UE (see embodiment 3). For example, a UE with a high positioning priority may be configured to be able to transmit and receive outside the DRX active time. A UE with a low positioning priority may be configured to be unable to transmit and receive outside the DRX active time. The LMF may notify the UE of the setting. For example, NAS signaling, or LPP and / or NRPPa signaling may be used for the notification. The notification from the LMF to the UE may be performed via the base station.

[0432] As another example, the setting may be performed by the AMF. The AMF may perform the setting using, for example, information regarding the load status of the communication network. For example, the AMF may configure a UE connected to a network with a heavy load in the communication network to disable UE transmission and reception outside the DRX active time. For a UE connected to a network with a light load in the communication network, the AMF may configure a UE to enable UE transmission and reception outside the DRX active time. The AMF may notify the UE of the setting. For example, NAS signaling may be used for the notification. The NAS signaling may include LPP and / or NRPPa signaling. As another example, the notification from the AMF to the UE may be performed via a base station.

[0433] According to the fourth embodiment, low-latency positioning is possible even for UEs in DRX.

[0434] Embodiment 5. A base station handover may be performed during the positioning procedure. For example, the source base station may notify the AMF of the measurement results of the positioning signal. The AMF may transfer the information to an LRF (Location Retrieval Function) (see Non-Patent Document 20 (TS23.501)). The UE may notify the target base station of information related to the positioning result. The target base station may transfer the information to the LRF. The above-mentioned operation may be performed, for example, when the LRF does not change before and after the UE handover.

[0435] As another example, the AMF may forward the information notified from the source base station to the LMF. The target base station may forward the information notified from the UE to the LMF. The above operation may be performed, for example, when the LMF does not change before and after the UE handover.

[0436] However, the present invention does not disclose how to handle handover during a positioning procedure when a base station has an LMF, which may result in a problem that a positioning procedure cannot be performed and / or a handover cannot be completed successfully when a base station has an LMF.

[0437] In the fifth embodiment, a method for solving the above-mentioned problems will be disclosed.

[0438] Positioning is continued between the UE and the source base station. The UE may transmit and receive positioning signals to and from the source base station. The UE may notify the source base station of information related to the reception result of the positioning signals. The source base station may use the information to calculate the position of the UE. After receiving a notification of the reception result of the positioning signals from the UE, the source base station may perform handover of the UE.

[0439] For example, the signaling of the handover request, the handover request acknowledgement, and / or the handover rejection between the source base station and the destination base station may be performed after the source base station receives the positioning signal reception result notification from the UE. After receiving the handover request acknowledgement from the destination base station, the source base station may instruct the UE to perform a handover. The UE may use the instruction to perform a handover from the source base station to the destination base station. This allows, for example, the handover process to be performed quickly after the positioning signal reception result is received.

[0440] The target base station may calculate the position of the UE. The source base station may transfer information regarding the positioning signal reception results to the target base station. The information may include the positioning signal reception results at the UE, the source base station, and / or the surrounding base stations, or may include information identifying the UE, the source base station, and / or the surrounding base stations, or may include a combination of the above information. The target base station may use the information to calculate the position of the UE. The source base station may include the information in a handover request and notify the target base station of the information. This may, for example, reduce the amount of signaling between base stations.

[0441] As another example, the signaling of the handover request, the handover request acknowledgement, and / or the handover rejection between the source base station and the target base station may be performed before receiving the positioning signal reception result notification from the UE. The handover instruction from the source base station to the UE may be performed after the positioning signal reception result notification from the UE to the source base station. This may enable, for example, a quick handover process after the UE position calculation. The UE may expect the handover instruction from the source base station to be transmitted after the positioning signal reception result notification to the source base station. This may, for example, avoid complexity related to positioning in the communication system.

[0442] The source base station may notify the destination base station of information related to the positioning of the UE. The destination base station may or may not use the information to perform positioning between the UE and the source base station. For example, the destination base station may use the information to perform positioning of the UE at the next positioning timing. This makes it possible to avoid complexity related to positioning in a communication system, for example. The source base station may notify the destination base station of the information by including it in a handover request. This makes it possible to reduce the amount of signaling between base stations, for example.

[0443] The following (1) to (11) are disclosed as examples of information related to UE positioning that is transmitted from the source base station to the destination base station.

[0444] (1) Information about the location of the UE.

[0445] (2) Information that identifies the UE.

[0446] (3) Information regarding the time of positioning.

[0447] (4) Information about the positioning cycle.

[0448] (5) Information regarding the priority of positioning.

[0449] (6) Information about positioning methods.

[0450] (7) Information about surrounding base stations.

[0451] (8) Information about your base station.

[0452] (9) Information about the base station's frame timing.

[0453] (10) Information about the UE measurement gap setting.

[0454] (11) A combination of (1) to (10) above.

[0455] The information related to (1) above may be, for example, a result of calculating the location of the UE derived by the source base station. The destination base station may use the information related to (1) above to control the UE after handover. This eliminates the need for the destination base station to recalculate the location of the UE. As a result, it is possible to prevent an increase in latency in positioning during handover.

[0456] The information related to (2) above may be, for example, a UE identifier. The identifier may be a UE-ID, or may be a Subscription Permanent Identifier (SUPI), Subscription Concealed Identifier (SUCI), Permanent Equipment Identifier (PEI), and / or 5G Globally Unique Temporary Identifier (5G-GUTI) disclosed in Non-Patent Document 20 (TS23.501). The target base station may use the information to recognize the UE to be positioned. This allows, for example, the target base station to quickly identify the UE to be positioned.

[0457] The information regarding (3) above may be, for example, information about the time when the source base station derived the location of the UE. The destination base station may use this information to derive the time when the next positioning of the UE should be performed. This makes it possible to prevent, for example, a gap in the timing of positioning the UE due to handover.

[0458] As another example, the information related to (3) above may be information about the time when the UE and / or the source base station acquired the positioning signal reception result. The destination base station may use this information to associate the UE's location with the time. This makes it possible to estimate the UE's location at a given time with high accuracy in a communication system, for example.

[0459] The information regarding (4) above may be notified, for example, in a system in which the UE requires periodic positioning. The target base station may use the information regarding (4) above to derive the next time to perform positioning of the UE. This makes it possible to prevent gaps in the timing of UE positioning due to handover, for example.

[0460] The information regarding (5) above may be, for example, the priority disclosed in embodiment 3. The target base station may use the information to perform priority control regarding transmission and reception of positioning signals. This allows, for example, the target base station to smoothly perform priority control regarding positioning of the UE.

[0461] The information regarding (6) above may be, for example, information indicating Multi-RTT or may be OTDOA (Observed Time Difference of Arrival). The information regarding Multi-RTT may be, for example, base station-led Multi-RTT (i.e., UE-assisted Multi-RTT) or UE-led Multi-RTT (i.e., UE-based Multi-RTT). The target base station may use this information to obtain information regarding the positioning method of the UE. This makes it possible, for example, to apply the same positioning method to the UE before and after handover. As a result, it is possible to quickly complete positioning before and after handover.

[0462] The information regarding (7) above may be, for example, information regarding an identifier of a neighboring base station (e.g., gNB-ID), a cell identifier (e.g., PCI, global cell ID), a DU identifier (e.g., DU-ID), a TRP identifier (e.g., TRP-ID), or a combination of the above information. The information regarding (7) above may include information regarding the locations of neighboring base stations, cells, DUs, and / or TRPs. The target base station may use this information to determine a base station to be used for positioning the UE. For example, the target base station may use the neighboring base stations used in positioning by the source base station as they are. This may reduce the latency of positioning, for example, during handover.

[0463] The information about (8) above may be, for example, information about the identifier of the own base station, the own cell, the own DU, and / or the own TRP, similar to the information about (7) above, or information about the location of the own base station, the own cell, the own DU, and / or the own TRP, or may be a plurality of the above.The destination base station may use this information to determine, for example, that the source base station is used as a neighboring base station for UE positioning.This, for example, can improve the flexibility of the positioning by the destination base station.

[0464] The information regarding (9) above may be, for example, information associating a specific frame, subframe, slot, and / or symbol in the source base station with a time. The associated information may be, for example, the time at the beginning or end of a specific frame. This information may be combined with information on the frame number in the source base station. The destination base station may use this information to derive the difference in frame timing between the destination base station and the source base station. This allows the destination base station to grasp, for example, the timing of transmitting and receiving a positioning signal in the source base station.

[0465] The information related to (10) above may be, for example, the measurement gap for transmitting and receiving a positioning signal in the UE, as disclosed in the first embodiment. The target base station may use this information to set the measurement gap between the target base station and the UE as is, or may change the measurement gap between the target base station and the UE. This enables, for example, quick measurement gap setting for the UE.

[0466] Another solution is disclosed. Part of the positioning procedure may be performed between the UE and the target base station. For example, a notification of the positioning signal reception result between the UE and the source base station may be performed between the UE and the target base station. This makes it possible to prevent communication loss between the UE and the NW due to, for example, deterioration of communication quality with the source base station during the positioning procedure.

[0467] For example, a handover request, a handover request acknowledgement, and / or a handover rejection signal between the source base station and the target base station may be transmitted before the transmission and reception of the positioning signal between the UE and the base station is completed. A handover instruction from the source base station to the UE may be transmitted after the transmission and reception of the positioning signal between the UE and the base station is completed. The aforementioned completion of the transmission and reception of the positioning signal may be, for example, the completion of the transmission and reception of the positioning signal at the serving base station and / or a neighboring base station. The aforementioned serving base station may be the source base station. The neighboring base station may notify the serving base station of the completion of the transmission and / or reception of the positioning signal. This allows, for example, the serving base station to know the completion of the transmission and reception of the positioning signal at the neighboring base station. The UE may expect the handover instruction from the source base station to be transmitted after the transmission of the uplink positioning signal from the UE itself, or before the notification of the downlink positioning signal reception result from the UE itself. This makes it possible to execute a handover before the communication quality between the UE and the source base station deteriorates, thereby improving the stability of the communication system.

[0468] The UE notifies the destination base station of information regarding the reception result of the positioning signal. The destination base station may forward the information to the source base station. The surrounding base station may notify the source base station of information regarding the reception result of the positioning signal at its own base station. The source base station may use the information to calculate the position of the UE. This, for example, eliminates the need for the source base station to notify the destination base station of information regarding positioning. As a result, it is possible to reduce the amount of signaling in the interface between base stations. The location calculation in the source base station may be performed, for example, when the destination base station does not have a positioning function. This makes it possible to continue positioning of the UE, for example, when the destination base station does not have a positioning function.

[0469] The source base station may inquire of the destination base station whether the destination base station has a positioning function, or may notify the destination base station of information indicating that a positioning procedure is being executed. The inquiry and / or the notification of the information may be included in, for example, a signaling of a handover request. The destination base station may notify the source base station whether the destination base station has a positioning function. The inquiry may be included in, for example, a signaling of a handover request acknowledgement, or may be included in a signaling of a handover reject. This, for example, eliminates the need to add new inter-base station signaling, thereby reducing complexity in the communication system.

[0470] The source base station may request the destination base station to transfer the reception result of the positioning signal. The request may be included in, for example, a signaling of a handover request. This may, for example, reduce the amount of signaling between base stations. As another example, a signaling different from that of the handover request may be used for the request. For example, a new signaling may be used. This may, for example, avoid the complexity of the signaling of the handover request.

[0471] As another example, the destination base station may calculate the position of the UE, and the source base station may notify the destination base station of information related to the positioning signal reception results. The source base station may notify the destination base station of information related to the positioning signal reception results at surrounding base stations, including the information. The surrounding base stations may notify the source base station of information related to the positioning signal reception results at their own base station. The source base station may notify the destination base station of information related to the UE positioning. The information may include the above-mentioned information (1) to (11) related to the UE positioning. The destination base station may use the information to calculate the position of the UE. This makes it possible to reduce the amount of processing at the source base station, for example.

[0472] As another example of a case where the destination base station calculates the position of the UE, the surrounding base station may notify the destination base station of information regarding the positioning signal reception result at the destination base station. The destination base station may establish an inter-base station interface with the surrounding base station. The source base station may notify the destination base station of information regarding the positioning signal reception result. The information regarding the positioning signal reception result may be, for example, only the positioning signal reception result received at the destination base station. The source base station may notify the destination base station of information regarding the positioning of the UE. The information may include the above-mentioned information (1) to (11) regarding the positioning of the UE. The destination base station may use the information to calculate the position of the UE or may establish an interface with the surrounding base station. This makes it possible to reduce the amount of processing at the source base station, for example.

[0473] Other solutions are disclosed. Positioning signals may be transmitted and received between the UE and the target base station. A positioning procedure may be performed between the UE and the target base station after handover. For example, a handover instruction from the source base station to the UE may be sent before a request from the LMF to the UE to start transmitting and receiving positioning signals. The UE may not transmit and receive positioning signals to and from the source base station. The source base station may abort the positioning procedure with the UE.

[0474] The source base station may notify the destination base station of information related to the positioning procedure. The information may be, for example, information indicating that the positioning procedure is being executed, or may include the above-mentioned information (1) to (11) related to the positioning of the UE. The information may be included in, for example, a handover request.

[0475] The target base station may use the information to perform a positioning procedure with the UE. For example, the target base station may perform positioning of the UE using the same settings used in the positioning by the source base station, or may perform positioning with the UE by partially changing the settings. As another example, the target base station may perform positioning with the UE using the surrounding base stations before handover as they are, or may perform positioning with the UE by partially changing, adding, or deleting the surrounding base stations. This makes it possible to reduce the latency of positioning during handover, for example.

[0476] The target base station may notify the source base station of the positioning settings at the target base station. The settings may be notified, for example, by being included in a handover request acknowledgement. The source base station may notify the UE of the settings. The settings may be included, for example, in a handover instruction to the UE. The UE may use the settings to transmit and receive positioning signals to and from the target base station. This may enable, for example, rapid positioning at the target base station.

[0477] If the target base station does not have a positioning function, handover may not be performed. For example, handover to the target base station may be canceled. The source base station may notify the target base station of information indicating that a positioning procedure is being executed. The information may be included in, for example, a handover request. The target base station may notify the source base station of a rejection of the handover request of the UE. For example, signaling of a handover request reject may be used for the notification. The notification of the rejection may include information regarding the reason. The reason may include information indicating that the target base station does not have a positioning function. The source base station may use the information not to perform handover to the target base station. This makes it possible, for example, to prevent the positioning function from being interrupted due to handover.

[0478] The source base station may perform handover processing to another base station, or may not perform handover.

[0479] As another example, if the target base station does not have positioning capabilities, the positioning procedure may be aborted and the source base station may perform a handover to the target base station.

[0480] The source base station and the target base station may coordinate whether to perform handover and / or whether to perform the positioning procedure. For example, the source base station may send a handover request multiple times to the target base station. The source base station may notify the target base station of information indicating that the positioning procedure is being performed. The information may be included in, for example, a handover request. The target base station may notify the source base station of a rejection of the handover request of the UE. For example, a handover request reject signaling may be used for the notification. The rejection notification may include information regarding the reason. The reason may include information indicating that the target base station does not have a positioning function. The source base station may use the information to decide to stop positioning the UE. The source base station may send a handover request to the target base station. The request may include, for example, information regarding the cancellation of the positioning procedure or information indicating that the UE positioning will not be performed. The target base station may use the notification to accept handover of the UE. The target base station may notify the source base station of a handover request acknowledgement. The source base station may instruct the UE to handover to the target base station. The source base station may include information on stopping positioning in the instruction. The UE may use the instruction to handover to the target base station. The UE may use the information to stop transmitting and receiving positioning signals. This may, for example, avoid complexity in the communication system.

[0481] As another example of the adjustment, the target base station may notify the source base station of information indicating that positioning will not be performed. The source base station may notify the target base station of information indicating that a positioning procedure is being executed. The information may be included in, for example, a handover request. The target base station may accept handover from the source base station. The target base station may notify a handover request acknowledgement. The notification may include information indicating that positioning will not be performed. The source base station may use the information to decide to stop the positioning process of the UE. The source base station may instruct the UE to hand over to the target base station. The source base station may include information regarding the stop of positioning in the instruction. The UE may use the instruction to hand over to the target base station. The UE may use the information to stop transmitting and receiving positioning signals. This, for example, makes it possible to reduce the amount of signaling between base stations.

[0482] As another example of the adjustment, the source base station may notify the destination base station of information regarding a policy on whether to permit handover. The policy information may be, for example, information indicating whether handover or positioning is to be prioritized. The source base station may notify the information by including the information in signaling of a handover request. The destination base station may use the information to determine whether to permit handover. For example, if the information indicates that handover is to be prioritized, the destination base station may accept the handover. As another example, if the information indicates that positioning is to be prioritized, the destination base station may reject the handover. This makes it possible to reduce signaling in the inter-base station interface, for example.

[0483] The solutions disclosed in the fifth embodiment may be used in combination. For example, positioning signal transmission and reception between the UE and the serving base station and / or the surrounding base station may be performed both before and after handover. For example, the source base station may instruct the UE to perform handover after a predetermined time has elapsed since starting transmission and reception of positioning signals between the UE and the source base station and / or the surrounding base station, after a predetermined time has elapsed since the source base station received a measurement report for handover from the UE, and / or after a predetermined time has elapsed since receiving a handover request acknowledgement from the target base station. The UE may perform handover to the target base station using the instruction. The UE may transmit and receive positioning signals with the target base station and / or the surrounding base station. The UE may notify the target base station of a positioning signal reception result. The notification may include, for example, a positioning signal transmission and reception result between the UE and the source base station and / or the surrounding base station. This makes it possible to prevent communication line disconnection due to deterioration in communication quality between the UE and the source base station due to a delay in handover, even if the UE that has received a handover instruction has not yet completed receiving downlink signals from the serving base station and / or surrounding base stations.

[0484] In the method disclosed in the fifth embodiment, the target base station may request the source base station to release the UE context after completing positioning. For example, after the source base station notifies the target base station of the result of UE location calculation, the target base station may request the source base station to release the UE context. This makes it possible to prevent the UE context from being released while the source base station is calculating the location using the UE context.

[0485] As another example, the source base station may release the UE context after the positioning is completed. The target base station may request the source base station to release the UE context before the positioning is completed. The source base station may suspend the release of the UE context until the positioning is completed. This allows, for example, the deletion of inter-base station signaling after the positioning is completed.

[0486] According to the fifth embodiment, it is possible to reduce the latency of positioning when a handover occurs during positioning.

[0487] In the present disclosure, the UE in which service data is generated is referred to as UE-TX. For example, if UE-TX is referred to as UE1 and UE-RX is referred to as UE2, when service data is generated in UE2 and the data is transmitted to UE1, it is advisable to apply the method of the present disclosure by treating UE2 as UE-TX and UE1 as UE-RX. Similar effects can be obtained.

[0488] The above-described embodiments and their modifications are merely examples, and the embodiments and their modifications can be freely combined. Furthermore, any of the components of the embodiments and their modifications can be modified or omitted as appropriate.

[0489] For example, in the above-described embodiments and their modifications, a subframe is an example of a time unit for communication in a fifth-generation base station communication system. It may also be a scheduling unit. In the above-described embodiments and their modifications, the processing described as being performed in subframe units may also be performed in TTI units, slot units, subslot units, or minislot units.

[0490] For example, the methods disclosed in the above-described embodiments and their modifications may be applied to services that use SL communication, not limited to V2X (Vehicle-to-everything) services, such as proximity-based services, public safety, communication between wearable devices, and communication between devices in factories.

[0491] For example, in each of the above-described embodiments and their modifications, the base station may be a cell, a DU, or a TRP (Transmission Reception Point).

[0492] Although the present disclosure has been described in detail, the above description is illustrative in all respects and is not restrictive. It is understood that countless variations not illustrated can be envisioned.

[0493] It should be noted that, within the scope of the present disclosure, the embodiments can be freely combined, modified, or omitted as appropriate.

Claims

1. A communication terminal device in a communication system, the communication system includes the communication terminal device, a base station device including a TRP (Transmission Reception Point) that performs wireless communication with the communication terminal device, and a Location Management Function (LMF) node; The communication terminal device is configured to receive information regarding the location of the TRP from the LMF node; The information regarding the location of the TRP includes information regarding the accuracy of the location of the TRP. Communications terminal equipment.

2. The communication terminal device receiving a downlink Positioning Reference Signal (PRS) from the TRP after receiving the information regarding the location of the TRP; calculating a position of the communication terminal device based on the measurement result of the downlink PRS; The communication terminal device according to claim 1.

3. the communications terminal is configured to determine the accuracy of the calculated position of the communications terminal; The communication terminal device according to claim 2.

4. The communication terminal device is configured to receive a Long Term Evolution Positioning Protocol (LPP) message containing the information on the location of the TRP using Radio Resource Control (RRC) or Non Access Stratum (NAS) signaling. The communication terminal device according to claim 1.

5. A base station device in a communication system, The communication system includes a communication terminal device, a base station device including a TRP (Transmission Reception Point) that performs wireless communication with the communication terminal device, and a Location Management Function (LMF) node; The base station device is configured to transmit information regarding the location of the TRP received from the LMF node to the communication terminal device via the TRP; The information regarding the location of the TRP includes information regarding the accuracy of the location of the TRP. Base station equipment.

6. A communication system comprising a communication terminal device, a base station device including a TRP (Transmission Reception Point) that performs wireless communication with the communication terminal device, and a Location Management Function (LMF) node, The communication terminal device is configured to receive information regarding the location of the TRP from the LMF node; The information regarding the location of the TRP includes information regarding the accuracy of the location of the TRP. Communication system.

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