Positioning method in wireless communication system and apparatus therefor

Abstract

According to at least one example disclosed in this specification, a first device may transmit assistance data for NTN-based terminal positioning to a location management function (LMF) node based on obtaining timing advance (TA) information for a first link between a non-terrestrial node of a non-terrestrial network (NTN) and the first device, a time difference between an uplink reference signal and a downlink reference signal is measured through a first link between a non-terrestrial node and a first device, and a measurement report including information on the time difference is transmitted to an LMF node, the TA information including common TA information between the non-terrestrial node and a reference point (RP) set on the first link, and the reference point (RP) is set on the first link. And the first device may report the common TA information to the LMF node through the assistance data.

Description

Technical Field

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a positioning method and apparatus in a wireless communication system supporting a non-terrestrial network. Background Art

[0002] In general, wireless communication systems are developing to cover a wide range in various ways to provide communication services such as audio communication services, data communication services, etc. Wireless communication is a multiple access system that can support communication with multiple users by sharing available system resources (e.g., bandwidth, transmission power, etc.). For example, the multiple access system can be any of a code division multiple access (CDMA) system, a frequency division multiple access (FDMA) system, a time division multiple access (TDMA) system, an orthogonal frequency division multiple access (OFDMA) system, and a single carrier frequency division multiple access (SC-FDMA) system. Summary of the invention

[0003] Technical issues

[0004] The present disclosure is directed to providing a method and apparatus for performing user equipment (UE) positioning through transmission and reception of reference signals in a wireless communication system supporting a non-terrestrial network.

[0005] Those skilled in the art will understand that the objectives that can be achieved using the present disclosure are not limited to those specifically described above, and the above and other objectives that can be achieved by the present disclosure will be more clearly understood from the following detailed description.

[0006] Technical Solution

[0007] In one aspect of the present disclosure, a method is provided herein, performed by a first device in a wireless communication system including a non-terrestrial network (NTN). The method may include the following steps: obtaining timing advance (TA) information based on a first link between a non-terrestrial node for the NTN and the first device; sending auxiliary data for positioning of a user equipment (UE) based on the NTN to a location management function (LMF) node; measuring the time difference between an uplink reference signal and a downlink reference signal; and sending a measurement report including information about the time difference to the LMF node. The TA information may include common TA information between a reference point (RP) configured on the first link and the non-terrestrial node. The first device may report the common TA information to the LMF node via the auxiliary data.

[0008] The non-terrestrial node may be a satellite, and the first device may be a terrestrial base station.

[0009] The first link may be a feeder link between the satellite and a ground base station.

[0010] The time difference between the uplink reference signal and the downlink reference signal may be the time difference between the sounding reference signal (SRS) and the positioning reference signal (PRS) at the RP. The PRS may be sent by the first device to the UE via the non-terrestrial node, and the SRS may be received by the first device from the UE via the non-terrestrial node.

[0011] For NTN based UE positioning, information about the UE downlink timing error may be provided to the LMF node.

[0012] The information about the UE downlink timing error may include an estimate of the downlink timing offset related to the Doppler effect.

[0013] Information about UE downlink timing error may be measured by the target UE for NTN-based UE positioning.

[0014] The information about the UE downlink timing error may be related to a time period during which the target UE measures a time difference between an uplink reference signal and a downlink reference signal.

[0015] NTN-based UE positioning can be performed independently of the Global Navigation Satellite System (GNSS).

[0016] In another aspect of the present disclosure, a processor-readable recording medium is provided herein, on which a program for executing the above method is recorded.

[0017] In another aspect of the present disclosure, a first device configured to execute the above method is provided herein.

[0018] In another aspect of the present disclosure, a method performed by a second device in a wireless communication system including an NTN is provided herein. The method may include the following steps: obtaining TA information based on a second link between a non-terrestrial node for the NTN and the second device; receiving first assistance data for UE positioning based on the NTN from an LMF node; measuring a time difference between an uplink reference signal and a downlink reference signal; and sending a measurement report including information about the time difference and the second assistance data to the LMF node. The TA information may include UE-specific TA information. The second device may report the timing error measured by the second device to the LMF node through the second assistance data.

[0019] The second device may be a UE. The second device may be a processing device that controls the UE.

[0020] The non-terrestrial node may be a satellite and the second device may be a UE.

[0021] The second link may be a serving link between the satellite and the UE.

[0022] The timing error measured by the second device may be a UE downlink timing error measured by the UE.

[0023] The time difference between the UL reference signal and the DL reference signal may be a difference between a timing at which the second device receives a PRS from the base station through the non-terrestrial node and a timing at which the second device sends an SRS to the base station through the non-terrestrial node.

[0024] The information about the UE downlink timing error may include an estimate of the downlink timing offset related to the Doppler effect.

[0025] The information about the UE downlink timing error may be related to a time period during which the UE measures a time difference between a UL reference signal and a downlink reference signal.

[0026] NTN-based UE positioning can be performed independently of GNSS.

[0027] In another aspect of the present disclosure, a second device configured to execute the above method is provided herein.

[0028] Beneficial Effects

[0029] According to an embodiment of the present disclosure, even in a non-terrestrial network, the position of a user equipment (UE) can be estimated through the transmission and reception of a radio access technology dependent (RAT dependent) reference signal, thereby providing a verifiable and highly reliable positioning technology.

[0030] Those skilled in the art will appreciate that the effects that can be achieved using the present disclosure are not limited to those specifically described above, and other advantages of the present disclosure will be more clearly understood from the following detailed description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Physical channels used in a 3rd Generation Partnership Project (3GPP) system as an exemplary wireless communication system and a general signal transmission method using the same are shown.

[0032] Figure 2 Shows the radio frame structure.

[0033] Figure 3 A resource grid showing time slots.

[0034] Figure 4 An exemplary mapping of physical channels in time slots is shown.

[0035] Figure 5 An exemplary physical downlink shared channel (PDSCH) reception and acknowledgement / negative acknowledgement (ACK / NACK) transmission process is shown.

[0036] Figure 6An exemplary physical uplink shared channel (PUSCH) transmission process is shown.

[0037] Figure 7 An example of setting a positioning protocol is shown.

[0038] Figure 8 An example of OTDOA is shown.

[0039] Fig. 9 An example of multiple RTT is shown.

[0040] Fig.10 A scenario showing a non-terrestrial network that a user equipment (UE) can access.

[0041] Fig.11 is a diagram for explaining UE-specific Timing Advance (TA) and common TA in NTN.

[0042] Fig.12 It is a diagram for explaining TA in various NTN scenarios.

[0043] Fig.13 It is a diagram for explaining the types of cells supported by a satellite.

[0044] Fig.14 It is a diagram for explaining the scheduling offset parameter in NTN.

[0045] Fig.15 It is a diagram for explaining multi-round trip time (multi-RTT) measurement based on a single satellite.

[0046] Fig.16 2 is a diagram for explaining the operation of a system supporting NTN according to an embodiment.

[0047] Fig.17 The operation of the first device according to one embodiment is shown.

[0048] Fig.18 The operation of the second device according to one embodiment is shown.

[0049] Figures 19 to 22 An example of the communication system 1 and the wireless device applicable to the present disclosure is shown.

[0050] Fig.23 An NTN suitable for use in the present disclosure is shown.

[0051] Fig.24 A very small aperture terminal (VSAT) suitable for use in the present disclosure is shown. DETAILED DESCRIPTION

[0052] Embodiments of the present disclosure are applicable to various wireless access technologies such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), and single carrier frequency division multiple access (SC-FDMA). CDMA can be implemented as a radio technology such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA can be implemented as a radio technology such as Global System for Mobile Communications (GSM) / General Packet Radio Service (GPRS) / Enhanced Data Rates for GSM Evolution (EDGE). OFDMA can be implemented as a radio technology such as Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wireless Fidelity (Wi-Fi)), IEEE 802.16 (Worldwide Interoperability for Microwave Access (WiMAX)), IEEE 802.20, and Evolved UTRA (E-UTRA). UTRA is part of Universal Mobile Telecommunications System (UMTS). 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is a part of Evolved UMTS (E-UMTS) using E-UTRA, and LTE-Advanced (A) is an evolved version of 3GPP LTE. 3GPP NR (New Radio or New Radio Access Technology) is an evolved version of 3GPP LTE / LTE-A.

[0053] As more and more communication devices require greater communication capacity, enhanced mobile broadband communications relative to traditional radio access technologies (RATs) are needed. In addition, large-scale machine-type communications (MTC), which can provide various services anytime and anywhere by connecting multiple devices and objects, is another important issue to be considered in the next generation of communications. Discussions are also underway to design communication systems that take into account services / UEs that are sensitive to reliability and latency. Therefore, discussions are underway to introduce new radio access technologies that take into account enhanced mobile broadband communications (eMBB), massive MTC, and ultra-reliable low-latency communications (URLLC). In the embodiments of the present disclosure, for simplicity, this technology will be referred to as NR (new radio or new RAT).

[0054] For the sake of brevity, 3GPP NR is mainly described, but the technical concept of the present disclosure is not limited thereto.

[0055] For background information, definitions of terms, and abbreviations related to the present disclosure, the following documents are incorporated by reference.

[0056] -38.211: Physical channels and modulation

[0057] -38.212: Multiplexing and channel coding

[0058] -38.213: Physical layer procedures for control

[0059] -38.214: Physical layer procedures for data

[0060] -38.215: Physical layer measurements

[0061] -38.300: NR and NG-RAN general description

[0062] -38.304: User Equipment (UE) procedures in idle mode and RRC inactive state

[0063] -38.321: Medium Access Control (MAC) Protocol Specification

[0064] -38.331: Radio Resource Control (RRC) protocol specification

[0065] -37.213: Introduction of channel access procedures for unlicensed spectrum for NR-based access

[0066] -36.355: LTE positioning protocol

[0067] -37.355: LTE positioning protocol

[0068] Terms and abbreviations -5GC: 5G Core Network -5GS: 5G System -AoA: Angle of Arrival -AP: Access Point -CID: Cell ID

[0069] -E-CID: Enhanced Cell ID

[0070] -GNSS: Global Navigation Satellite System -GPS: Global Positioning System -LCS: Location Services -LMF: Location Management Function -LPP: LTE Positioning Protocol -MO-LR: Mobile Originated Location Request -MT-LR: Mobile Terminated Location Request -NRPPa: NR Positioning Protocol A

[0071] -OTDOA: Observed Time Difference of Arrival -PDU: Protocol Data Unit -PRS: Positioning Reference Signal -RRM: Radio Resource Management -RSSI: Received Signal Strength Indicator -RSTD: Reference Signal Time Difference -ToA: Time of Arrival -TP: Transmission Point -TRP: Transmit and Receive Point -UE: User Equipment -SS: Search Space -CSS: Common Search Space -USS: UE-Specific Search Space -PDCCH: Physical Downlink Control Channel -PDSCH: Physical Downlink Shared Channel -PUCCH: Physical Uplink Control Channel -PUSCH: Physical Uplink Shared Channel -DCI: Downlink Control Information -UCI: Uplink Control Information -SI: System Information -SIB: System Information Block -MIB: Master Information Block -RRC: Radio Resource Control -DRX: Discontinuous Reception

[0072] -RNTI: Radio Network Temporary Identifier

[0073] -CSI: Channel State Information

[0074] -PCell: Primary cell

[0075] -SCell: Secondary cell

[0076] -PSCell: Primary SCG (Secondary Cell Group) cell

[0077] -CA: Carrier Aggregation

[0078] -WUS: wake-up signal

[0079] -TX: Transmitter

[0080] -RX: Receiver

[0081] In a wireless communication system, a user equipment (UE) receives information from a base station (BS) through a downlink (DL) and transmits information to the BS through an uplink (UL). The information transmitted and received by the BS and the UE includes data and various control information, and includes various physical channels according to the type / purpose of the information transmitted and received by the UE and the BS.

[0082] Figure 1 Physical channels used in the 3GPP NR system and a general signal transmission method using the same are shown.

[0083] When the UE is powered on again from a power-off state or enters a new cell, in step S101, the UE performs an initial cell search process (e.g., establishes synchronization with the BS). To this end, the UE receives a synchronization signal block (SSB) from the BS. The SSB includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a physical broadcast channel (PBCH). The UE establishes synchronization with the BS based on the PSS / SSS and obtains information such as a cell identity (ID). The UE can obtain broadcast information in the cell based on the PBCH. The UE can receive a DL reference signal (RS) during the initial cell search process to monitor the DL channel status.

[0084] After the initial cell search, the UE may acquire more specific system information by receiving a physical downlink control channel (PDCCH) and receiving a physical downlink shared channel (PDSCH) based on information of the PDCCH in step S102.

[0085] The UE may perform a random access procedure to access the BS in steps S103 to S106. For random access, the UE may send a preamble to the BS on a physical random access channel (PRACH) (S103) and receive a response message to the preamble on a PDCCH and a PDSCH corresponding to the PDCCH (S104). In the case of contention-based random access, the UE may perform a contention resolution procedure by further sending a PRACH (S105) and receiving a PDCCH and a PDSCH corresponding to the PDCCH (S106).

[0086] After the foregoing process, the UE may receive PDCCH / PDSCH (S107) and send a physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) (S108) as a general downlink / uplink signal transmission process. The control information sent from the UE to the BS is called uplink control information (UCI). UCI includes hybrid automatic repeat and request confirmation / negative determination (HARQ-ACK / NACK), scheduling request (SR), channel state information (CSI), etc. CSI includes channel quality indicator (CQI), precoding matrix indicator (PMI), rank indicator (RI), etc. Although UCI is usually sent on PUCCH, UCI may be sent on PUSCH when control information and business data need to be sent simultaneously. In addition, UCI may be sent aperiodically via PUSCH according to the request / command of the network.

[0087] Figure 2 The radio frame structure is shown. In NR, uplink transmission and downlink transmission are configured in frames. Each radio frame has a length of 10ms and is divided into two 5ms half frames (HF). Each half frame is divided into five 1ms subframes (SF). A subframe is divided into one or more time slots, and the number of time slots in a subframe depends on the subcarrier spacing (SCS). Depending on the cyclic prefix (CP), each time slot includes 12 or 14 orthogonal frequency division multiplexing (OFDM) symbols. When a normal CP is used, each time slot includes 14 OFDM symbols. When an extended CP is used, each time slot includes 12 OFDM symbols.

[0088] Table 1 exemplarily shows that the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary according to the SCS when a normal CP is used.

[0089] [Table 1]

[0090] <![CDATA[SCS(15*2 u )]]> <![CDATA[N slot symb ]]> <![CDATA[N frame,u slot ]]> <![CDATA[N subframe,u slot ]]> 15KHz(u=0) 14 10 1 30KHz(u=1) 14 20 2 60KHz(u=2) 14 40 4 120KHz(u=3) 14 80 8 240KHz(u=4) 14 160 16

[0091] *N slot symb : The number of symbols in a time slot

[0092] *N frame,u slot : Number of time slots in a frame

[0093] *N subframe,u slot : Number of time slots in a subframe

[0094] Table 2 shows that the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary according to the SCS when the extended CP is used.

[0095] [Table 2]

[0096] <![CDATA[SCS(15*2 u )]]> <![CDATA[N slot symb ]]> <![CDATA[N frame,u slot ]]> <![CDATA[N subframe,u slot ]]> 60KHz(u=2) 12 40 4

[0097] The structure of the frame is only an example. The number of subframes, the number of time slots, and the number of symbols in a frame may vary.

[0098] In the NR system, OFDM parameter sets (e.g., SCS) may be configured differently for multiple cells aggregated for one UE. Therefore, the (absolute time) duration of a time resource (e.g., SF, time slot, or TTI) (referred to as a time unit (TU) for simplicity) consisting of the same number of symbols may be configured differently between aggregated cells. Here, the symbol may include an OFDM symbol (or CP-OFDM symbol) and an SC-FDMA symbol (or a discrete Fourier transform-spread-OFDM (DFT-s-OFDM) symbol).

[0099] Figure 3 A resource grid showing a time slot. A time slot includes multiple symbols in the time domain. For example, when a normal CP is used, a time slot includes 14 symbols. However, when an extended CP is used, a time slot includes 12 symbols. A carrier includes multiple subcarriers in the frequency domain. A resource block (RB) is defined as a plurality of consecutive subcarriers (e.g., 12 consecutive subcarriers) in the frequency domain. A bandwidth part (BWP) may be defined as a plurality of consecutive physical RBs (PRBs) in the frequency domain and corresponds to a single parameter set (e.g., SCS, CP length, etc.). A carrier may include up to N (e.g., five) BWPs. Data communication may be performed via enabled BWPs, and only one BWP may be enabled for a UE. In a resource grid, each element is referred to as a resource element (RE), and a complex symbol may be mapped to each RE.

[0100] Figure 4An example of mapping physical channels in a time slot is shown. In the NR system, a frame is characterized by a self-contained structure in which a DL control channel, DL or UL data, and a UL channel can all be included in one time slot. For example, the first N symbols of a time slot can be used to carry a DL channel (e.g., PDCCH) (hereinafter referred to as a DL control region), and the last M symbols of a time slot can be used to carry a UL channel (e.g., PUCCH) (hereinafter referred to as a UL control region). Each of N and M is an integer equal to or greater than 0. The resource region (hereinafter referred to as the data region) between the DL control region and the UL control region can be used to send DL data (e.g., PDSCH) or UL data (e.g., PUSCH). The guard period (GP) provides a time gap for switching from a transmit mode to a receive mode or from a receive mode to a transmit mode. Some symbols in a subframe when switching from DL to UL can be configured as GPs.

[0101] PDCCH transmits DCI. For example, PDCCH (i.e., DCI) may carry information about the transmission format and resource allocation of the DL shared channel (DL-SCH), resource allocation information of the uplink shared channel (UL-SCH), paging information about the paging channel (PCH), system information about DL-SCH, information about resource allocation of high-level control messages (e.g., RAR sent on PDSCH), transmit power control commands, information about the activation / release of the configured scheduling, etc. DCI includes a cyclic redundancy check (CRC). The CRC is masked using various identifiers (IDs) (e.g., radio network temporary identifier (RNTI)) according to the owner or purpose of the PDCCH. For example, if the PDCCH is used for a specific UE, the CRC is masked by the UE ID (e.g., cell-RNTI (C-RNTI)). If the PDCCH is used for a paging message, the CRC is masked by the paging-RNTI (P-RNTI). If the PDCCH is for system information (eg, system information block (SIB)), the CRC is masked by a system information RNTI (SI-RNTI). When the PDCCH is for RAR, the CRC is masked by a random access-RNTI (RA-RNTI).

[0102] Figure 5 An exemplary PDSCH reception and ACK / NACK transmission process is shown. Figure 5, the UE may detect the PDCCH in time slot #n. The PDCCH includes DL scheduling information (e.g., DCI format 1_0 or DCI format 1_1), and indicates the DL assignment to PDSCH offset K0 and PDSCH-HARQ-ACK report offset K1. After receiving the PDSCH in time slot #(n+K0) according to the scheduling information of time slot #n, the UE may send UCI on the PUCCH in time slot #(n+K1). The UCI may include a HARQ-ACK response to the PDSCH. In the case where the PDSCH is configured to carry up to one TB, the HARQ-ACK response may be configured in one bit. In the case where the PDSCH is configured to carry up to two TBs, if spatial bundling is not configured, the HARQ-ACK response may be configured in 2 bits, and if spatial bundling is configured, the HARQ-ACK response may be configured in 1 bit. When slot #(n+K1) is designated as HARQ-ACK transmission timing of a plurality of PDSCHs, UCI transmitted in slot #(n+K1) includes HARQ-ACK responses to the plurality of PDSCHs.

[0103] Figure 6 An exemplary PUSCH transmission process is shown. Figure 6 , the UE may detect the PDCCH in slot #n. The PDCCH includes DL scheduling information (e.g., DCI format 1_0 or 1_1). Then, the UE may send the PUSCH in slot #(n+K2) according to the scheduling information in slot #n. The PUSCH includes the UL-SCH TB.

[0104] position

[0105] Positioning may refer to determining the geographic location and / or velocity of a UE based on measurements of radio signals. Location information may be requested and reported by a client (e.g., an application) associated with the UE. Location information may also be requested by a client within or connected to the core network. Location information may be reported in a standard format (e.g., a format based on cells or geographic coordinates) together with an estimated error in the location and velocity of the UE and / or the positioning method used for positioning.

[0106] Figure 7 is a diagram illustrating an exemplary positioning protocol configuration for positioning a UE, to which various embodiments are applicable.

[0107] The LTE Positioning Protocol (LPP) can be used as a point-to-point protocol between a location server (E-SMLC and / or SLP and / or LMF) and a target device (UE and / or SET) for positioning the target device using location-related measurements obtained from one or more reference resources. The target device and the location server can exchange measurement and / or location information based on signal A and / or signal B via LPP.

[0108] NRPPa may be used for information exchange between reference sources (access nodes and / or BSs and / or TPs and / or NG-RAN nodes) and location servers.

[0109] The NRPPa protocol provides the following functions.

[0110] -E-CID position information transmission. This function allows the reference source to exchange position information with the LMF for E-CID positioning.

[0111] -OTDOA information transfer. This function allows the reference source to exchange information with the LMF for OTDOA positioning.

[0112] - Reporting of general error conditions. This feature allows reporting of general error conditions for which no function-specific error messages have been defined.

[0113] Positioning methods supported in NG-RAN may include GNSS, OTDOA, E-CID, air pressure sensor positioning, WLAN positioning, Bluetooth positioning, TBS, uplink time difference of arrival (UTDOA), etc. Although any one positioning method may be used for UE positioning, two or more positioning methods may be used for UE positioning.

[0114] OTDOA (Observed Time Difference of Arrival)

[0115] Figure 8 is a diagram illustrating an observed time difference of arrival (OTDOA) positioning method to which various embodiments are applicable.

[0116] The OTDOA positioning method uses the time measured for DL ​​signals received by the UE from multiple TPs including eNB, ng-eNB, and PRS-only TPs. The UE uses the location assistance data received from the location server to measure the time of the received DL signals. The location of the UE can be determined based on such measurement results and the geographic coordinates of neighboring TPs.

[0117] A UE connected to a gNB may request a measurement gap from a TP to perform OTDOA measurements. If the UE does not know the SFN of at least one TP in the OTDOA assistance data, the UE may use autonomous gaps to obtain the SFN of the OTDOA reference cell before requesting a measurement gap for performing reference signal time difference (RSTD) measurements.

[0118] Here, RSTD may be defined as the minimum relative time difference between two subframe boundaries received from the reference cell and the measurement cell. That is, RSTD may be calculated as the relative time difference between the start time of the subframe received from the measurement cell and the start time of the subframe from the reference cell that is closest to the subframe received from the measurement cell. The reference cell may be selected by the UE.

[0119] For accurate OTDOA measurement, it is necessary to measure the time of arrival (ToA) of signals received from three or more TPs or BSs distributed geographically. For example, the ToA of each of TP 1, TP 2, and TP 3 can be measured, and the RSTD of TP 1 and TP 2, the RSTD of TP 2 and TP 3, and the RSTD of TP 3 and TP 1 are calculated based on the three ToA values. A geometric hyperbola is determined based on the calculated RSTD values, and the intersection of the curves of the hyperbola can be estimated as the position of the UE. In this case, the accuracy and / or uncertainty of each ToA measurement may occur, and according to the measurement uncertainty, the estimated position of the UE can be referred to as a specific range.

[0120] For example, the RSTD of two TPs may be calculated based on the following Equation 1.

[0121] [Formula 1]

[0122]

[0123] In equation 1, c is the speed of light, {x t ,y t} are the (unknown) coordinates of the target UE, {x i ,y i} are the (known) coordinates of the TP, and {x1, y1} are the coordinates of the reference TP (or another TP). i -T1) is the transmission time offset between the two TPs, called the “real time difference” (RTD), n i and n1 is the UE ToA measurement error value.

[0124] E-CID (Enhanced Cell ID)

[0125] In the cell ID (CID) positioning method, the location of the UE can be measured based on the geographic information of the UE's serving ng-eNB, serving gNB and / or serving cell. For example, the geographic information of the serving ng-eNB, serving gNB and / or serving cell can be obtained through paging, registration, etc.

[0126] In addition to the CID positioning method, the E-CID positioning method may also use additional UE measurements and / or NG-RAN radio resources to improve the UE position estimate. Although the E-CID positioning method may partially utilize the same measurement method as the measurement control system on the RRC protocol, additional measurements only for UE position measurement are generally not performed. In other words, additional measurement configurations or measurement control messages may not be provided for UE position measurement. The UE is not expected to request additional measurement operations only for position measurement, and the UE may report measurement values ​​obtained by a generally measurable method.

[0127] For example, the serving gNB may use the E-UTRA measurements provided by the UE to implement the E-CID positioning method.

[0128] For example, the measurement elements that can be used for E-CID positioning may be as follows.

[0129] -UE measurements: E-UTRA Reference Signal Received Power (RSRP), E-UTRA Reference Signal Received Quality (RSRQ), UE E-UTRA Receive (Rx)-Transmit (Tx) Time Difference, GERAN / WLAN Reference Signal Strength Indicator (RSSI), UTRAN Common Pilot Channel (CPICH) Received Signal Code Power (RSCP) and / or UTRAN CPICH Ec / Io

[0130] -E-UTRAN measurements: ng-eNB Rx-Tx time difference, timing advance (T ADV ) and / or AoA

[0131] Here, T ADV It can be divided into type 1 and type 2 as follows.

[0132] T ADV Type 1 = (ng-eNB Rx-Tx time difference) + (UE E-UTRA Rx-Tx time difference)

[0133] T ADV Type 2 = ng-eNB Rx-Tx time difference

[0134] AoA can be used to measure the direction of the UE. AoA is defined as the estimated counterclockwise angle of the UE relative to the eNB / TP. In this case, the geographic reference direction may be north. The eNB / TP may use UL signals such as SRS and / or DMRS to perform AoA measurements. The measurement accuracy of AoA increases as the arrangement of the antenna array increases. When the antenna array is arranged at the same interval, the signals received at adjacent antenna elements may have a constant phase rotation.

[0135] UTDOA (Uplink Time Difference of Arrival)

[0136] UTDOA is a method of determining the location of a UE by estimating the arrival time of an SRS. When calculating the estimated SRS arrival time, the serving cell can be used as a reference cell to estimate the location of the UE by the arrival time difference with another cell (or base station / TP). To implement UTDOA, the E-SMLC may indicate the serving cell of the target UE in order to instruct the target UE to send an SRS. In addition, the E-SMLC may provide configurations such as periodic / aperiodic SRS, bandwidth, and frequency / group / sequence hopping.

[0137] Multiple RTT (Round Trip Time)

[0138] Fig. 9 is a diagram illustrating an exemplary multiple round trip time (multi-RTT) positioning method to which various embodiments are applicable.

[0139] Reference Fig. 9 (a) shows an exemplary RTT process, in which the initiating device and the responding device perform ToA measurement, and the responding device provides the ToA measurement to the initiating device for RTT measurement (calculation). The initiating device can be a TRP and / or a UE, and the responding device can be a UE and / or a TRP.

[0140] The initiating device may send an RTT measurement request, and the responding device may receive the RTT measurement request (1301).

[0141] The initiating device may send an RTT measurement signal at t0, and the responding device may obtain a ToA measurement at t1 (1303).

[0142] The responding device may send an RTT measurement signal at t2, and the initiating device may obtain a ToA measurement at t3 (1305).

[0143] The responding device may send information about [t2-t1], and the initiating device may receive the information and calculate the RTT through Equation 2 (1307). The information (1305) may be sent and received based on a separate signal or in an RTT measurement signal.

[0144] [Formula 2]

[0145] RTT = t3-t0-[t2-t1]

[0146] Reference Fig. 9 (b), RTT may correspond to double ranging between two devices. Positioning estimation may be performed from the corresponding information, and multi-point positioning may be used for positioning estimation. d1, d2, and d3 may be determined based on the measured RTT, and the location of the target device may be determined as the intersection of the circumferences of circles with radii d1, d2, and d3 centered at BS1, BS2, and BS3 (or TRP), respectively.

[0147] NTN (Non-Terrestrial Network)

[0148] A non-terrestrial network (NTN) refers to a network or network segment that is configured to use radio resources in a satellite or unmanned aerial system (UAS) platform.

[0149] In order to ensure wider coverage or provide wireless communication services in places where it is not easy to install wireless communication BS, non-terrestrial network (NR NTN) or LTE NTN services have been considered. NR or LTE services, which are existing terrestrial network (TN) services, provide wireless communication services to UEs by installing corresponding BSs on the ground, but NTN services provide wireless communication services to UEs by installing BSs on the ground where artificial satellites (geostationary orbit, low earth orbit, medium earth orbit, etc.), airplanes, unmanned aircraft, drones, etc. are not, rather than installing BSs on the ground. Scenarios such as HAPS (high altitude platform) and ATG (air-to-ground) may be included.

[0150] For (Rel-17 / 18) NTN services, frequency division duplex (FDD) is mainly considered (however, this does not mean that time division duplex (TDD) is completely excluded). It is assumed that the UE has GNSS capability.

[0151] Fig.10 An exemplary scenario of an NTN that a UE can access is shown. Specifically, Fig.10 (a) shows the NTN scenario based on transparent payload, Fig.10 (b) shows a NTN scenario based on a regenerative payload. The transparent payload plays a role such as RF filtering, frequency conversion and amplification. Therefore, the waveform signal in the transmission payload is not changed. On the other hand, the regenerative payload plays a role such as RF filtering, frequency conversion and amplification as well as demodulation / decoding, switching and / or routing, coding / modulation. Therefore, all or some BS functions can be considered to be installed on the satellite.

[0152] NTN can generally be characterized by the following factors.

[0153] - One or more satellite gateways for connecting the NTN to the public data network:

[0154] Geostationary orbit (GEO) satellites may be provided from one or more satellite gateways located within the satellite's target coverage area (e.g., regional or even continental coverage). UEs within a cell may be assumed to be served by only one satellite gateway;

[0155] Non-GEO satellites may be continuously served by one or more satellite gateways. The system may ensure service and feeder link continuity of the serving satellite gateway for a period of time sufficient for mobility anchoring and handover.

[0156] -Feeder link or wireless link between satellite gateway and satellite (or UAS platform)

[0157] -Service link or wireless link between UE and satellite (or UAS platform)

[0158] - A satellite (or UAS platform) for implementing one of a transparent or regenerative (including onboard processing) payload. A satellite (or UAS platform) may typically generate multiple beams in a service area having boundaries defined by the field of view of the satellite (or UAS platform). The coverage of the beams may typically be elliptical. The field of view of the satellite (or UAS platform) may be determined based on the onboard antenna diagram and the minimum elevation angle.

[0159] Transparent Payload: RF filtering and frequency conversion and amplification. Therefore, the waveform signal is repeated unchanged by the payload.

[0160] Regenerative payload: demodulation / decoding, switching and / or routing, coding / modulation, and RF filtering and frequency conversion and amplification. This is effectively equivalent to having all or some of the functionality of a BS (e.g., gNB) on a satellite (or UAS platform).

[0161] - Inter-satellite Link (ISL) in case of satellite constellation. For this purpose, satellites need to regenerate payload. ISL can operate at RF frequency or broadband.

[0162] -The UE can be served by a satellite (or UAS platform) within the target service area.

[0163] Table 3 below shows examples of satellite (or UAS platform) types.

[0164] [Table 3]

[0165]

[0166] generally,

[0167] -GEO satellites and UAS can be used to provide continental, regional or local services.

[0168] - Low Earth Orbit (LEO) and Medium Earth Orbit (MEO) groups can be used to provide services in both the Northern and Southern Hemispheres. In some cases, the constellation can also provide global coverage including the polar regions. For the latter, appropriate orbital inclination, sufficient generated beams and inter-satellite links may be required.

[0169] Highly elliptical orbit (HEO) satellite systems may also be considered.

[0170] Hereinafter, a wireless communication system in NTN including the following six reference scenarios will be described.

[0171] -Circular track and nominal station holding platform

[0172] -Maximum Round Trip Delay (RTD) constraint

[0173] - Highest Doppler constraint

[0174] - Transparent or regenerative payload

[0175] - One case with ISL and one case without ISL. In case of inter-satellite link, regeneration of the payload may be required.

[0176] - Fixed or steerable beams resulting in mobile or fixed coverage on the ground.

[0177] Six reference scenarios are considered in Tables 4 and 5.

[0178] [Table 4]

[0179]

[0180] [Table 5]

[0181]

[0182]

[0183] Reference 1: Each satellite can use beamforming technology to steer the beam to a fixed point on the earth. This can be applied to the time corresponding to the visibility of the satellite. Reference 2: The maximum delay variation in the beam (UE is fixed on the ground) can be calculated based on the minimum elevation angle (Min Elevation angle) of both the gateway and the UE.

[0184] Reference 3: The maximum differential delay in a beam can be calculated based on the diameter of the maximum beam coverage at the lowest point (at nadir).

[0185] Reference 4: The speed of light used to calculate delay can be 299,792,458 m / s.

[0186] Reference 5: The size of the GEO maximum beam coverage can be determined based on current GEO high throughput system technology under the assumption that there are spot beams at the edge of the coverage (low altitude).

[0187] Reference 6: The maximum differential delay at the cell level may be calculated taking into account the beam-level delay of the maximum beam size. When the beam size is small or medium, the cell may include two or more beams. However, the cumulative differential delay of all beams in the cell cannot exceed the maximum differential delay at the cell level in Table 10.

[0188] The NTN related descriptions of this specification are applicable to NTN GEO scenarios as well as any non-geostationary orbit (NGSO) scenarios with circular orbits having an altitude equal to or greater than 600 km.

[0189] Fig.11 is a diagram for explaining UE-specific Timing Advance (TA) and common TA in NTN.

[0190] In NTN, the distance between the satellite and the UE changes due to the movement of the satellite, regardless of the movement of the UE. To overcome this problem, the UE can determine the position of the UE based on GNSS and calculate the UE-specific TA as the round trip delay (RTD) between the UE and the satellite based on the satellite orbit information provided by the BS.

[0191] Common TA may refer to the RTD between the gNB on the ground (i.e., the reference point) and the satellite. Here, the reference point may mean where the DL and UL frame boundaries match. Common TA may be defined as what the BS indicates to the UE. If the reference point is on the satellite, the common TA may not be indicated. If the reference point is at the gNB on the ground, the common TA may be used to compensate for the RTD between the gNB and the satellite.

[0192] like Fig.11 As shown in FIG. 1 , in Rel-17 NTN, the UE can autonomously calculate the TA based on the UE's GNSS capability and the information provided by the BS (e.g., ephemeris information), which is called the UE-specific TA. The TA calculated based on the public TA parameters provided by the BS can be called the public TA. Table 6 shows the final TA defined in TS 38.211 based on this.

[0193] [Table 6]

[0194]

[0195] Fig.12 is a diagram for explaining TA in each of a regeneration payload-based NTN scenario and a transparent payload-based NTN scenario.

[0196] Fig.12 (a) shows an NTN scenario based on regenerated payload. The common TA (Tcom) (common to all UEs) can be calculated as 2D0 (distance between satellite and reference signal) / c, and the UE-specific differential TA (TUEx) of the xth UE (UEx) can be calculated as 2(D1x-D0) / c. The total TA (Tfull) can be calculated as Tcom+TUEx. Here, D1x is the distance between the satellite and UEx, and c is the speed of light.

[0197] Fig.12 (b) shows an NTN scenario based on transparent payload. The common TA (Tcom) (common to all UEs) can be calculated as 2(D01+D02) / c, and the UE-specific differential TA (TUEx) of the xth UE (UEx) can be calculated as 2(D1x-D0) / c. The total TA (Tfull) can be calculated as Tcom+TUEx. Here, D01 is the distance between the satellite and the reference point, and D02 is the distance between the satellite and the BS located on the ground.

[0198] Fig.13 It is a diagram used to illustrate the cell types supported by the satellite.

[0199] Reference Fig.13 According to the supported cell types, cells can be divided into (a) earth-fixed beam / cell and (b) mobile cell. Earth-fixed cell (a) means that the cell is maintained in a specific position on the earth's surface permanently or for a specific service duration based on the beam steering capability of the satellite. Earth mobile cell (b) means that the cell is continuously moving on the earth's surface based on a fixed beam served by a satellite (rather than using the beam steering capability of the satellite).

[0200] The frequency bands considered for NR NTN services are as follows: For bands below 6 GHz, the 2 GHz band is being considered (L band: 1 to 2 GHz, S band: 2 to 4 GHz); For bands above 6 GHz, the DL 20 GHz band and the UL 30 GHz band (Ka band: 26.5 to 40 GHz) are being considered. In particular, the NTN bands supported in Rel-17 are as follows.

[0201] -S band (n256): UL 1980-2010MHz / DL 2170-2200MHz

[0202] -L band (n255): UL 1626.5-1660.5MHz / DL 1525-1559MHz

[0203] Fig.14 : is a diagram for explaining the scheduling offsets K_offset and K_mac in NTN. In order to efficiently operate NTN with very long RTT, scheduling offsets: K_offset and K_mac are introduced.

[0204] Reference Fig.14 , K_offset represents the offset value indicating the RTT of the UL time synchronization reference point (RP). K_offset is the sum of the service link RTT and the common TA (if indicated).

[0205] In addition, k_mac represents an offset value indicating the RTT between the RP and the gNB.

[0206] In Rel-17, two ephemeris formats are supported, and their contents are as follows.

[0207] 1) Position and velocity state vector ephemeris format: 132 bits (<17 bytes)

[0208] - The field size of position (x, y, z) (m) is 78 bits

[0209] - The field size of speed (vx, vy, vz) (m / s) is 54 bits

[0210] 2) Orbital parameter ephemeris format: 164 bits (<21 bytes)

[0211] - The semi-major axis "α" (m) is 33 bits

[0212] - Eccentricity "e" is 20 bits

[0213] - 28 bits for the argument of anomaly "ω" (rad)

[0214] - Longitude of ascending node "Ω" (rad) is 28 bits

[0215] - Tilt angle "i" (rad) is 27 bits

[0216] - Mean anomaly "M" (rad) at epoch time is 28 bits

[0217] In satellite-based communications, circular polarization is primarily used to enhance the straightness of radio waves. In Rel-17, system information (or SIB) signaling was introduced to inform UEs of the polarization information used by the satellite. The polarization types included in the signaling are linear, right-hand circular polarization (RHCP), and left-hand circular polarization (LHCP).

[0218] Multi-RTT based positioning method for NTN

[0219] Hereinafter, embodiments of RAT-dependent positioning techniques (eg, multi-RTT, DL / UL-TDOA, etc.) in NTN will be described.

[0220] As a positioning technology in NTN, in addition to GNSS (GPS) based positioning, RAT dependent positioning technology is being considered. The main purpose of RAT dependent positioning technology is to prevent malicious manipulation of UE GNSS information.

[0221] In NTN, the UE location verified by the network (network verified UE location) may be determined by RAT dependent positioning techniques. Table 7 is an excerpt of the following specifications TS23.501 and TS23.502 related to the network verified UE location.

[0222] [Table 7]

[0223]

[0224]

[0225] This network (NW) verification procedure may be considered for the following use cases: lawful interception, emergency calls, public warning systems, charging and billing, i.e., in case of changes in national / regional laws and / or regulations. To perform the NW verification procedure, the NW may consider RAT-based positioning in addition to the UE's GNSS-based location information. In a recent standards meeting, an agreement was reached on NW verification of UE location as shown in Table 8.

[0226] [Table 8]

[0227]

[0228]

[0229] As shown in Table 8, multi-RTT and / or TDOA are considered as RAT-dependent positioning techniques.

[0230] Refer to above Fig. 9 In the described multi-RTT technique for TN, UL SRS and DLPRS for positioning may be used. The location server may provide DL PRS configuration to the UE, and the BS may configure SRS to the UE. Specifically, the UE may receive DLPRS from the BS and send UL SRS to the BS. The UE measures and reports UE RX-TX time difference measurement for multiple pairs of TRP / BS. From the perspective of the UE, the UE RX-TX time difference measurement refers to the time difference from PRS reception to SRS transmission. The BS measures and reports gNB RX-TX time difference measurement for multiple pairs of TRP / BS. From the perspective of the BS, the gNB RX-TX time difference measurement refers to the time difference from PRS transmission to SRS reception. The gNB RX-TX time difference measurement is greater than the UE RX-TX time difference measurement, and the distance between the UE and the corresponding BS may be calculated from the time difference between the gNB RX-TX time difference measurement and the UE RX-TX time difference measurement. That is, the RTT may be calculated based on the difference between the UE Rx-Tx time difference and the gNB Rx-Tx time difference. Assuming that the UL and DL propagation delays are the same, a value equivalent to half of the UL and DL propagation delays can be regarded as a common propagation delay applied to both DL and UL, because gNB Rx-Tx time difference-UE Rx-Tx time difference=UL propagation delay+DL propagation delay is satisfied. Although the multi-RTT technique has the advantage of being robust to synchronization errors, the multi-RTT technique requires a relatively long delay time and has a structure that is not conducive to obtaining multiple measurements.

[0231] Fig.15 is a diagram for explaining multi-RTT measurement based on a single satellite.

[0232] Specifically, Fig.15An example of applying the technology of measuring multiple RTTs based on multiple BSs to NTN based on a single satellite is shown. A single satellite measures multiple RTTs via multiple timings, and a location server (eg, LMF) calculates information about the UE location based on the multiple RTTs.

[0233] In an embodiment of the present disclosure, a method for efficiently applying the multi-RTT technology based on a single satellite is proposed.

[0234] Proposal 1

[0235] The BS / TRP may signal the LMF with information about the error and / or delay of the RTT calculation. The error / delay information may include some or all of the following.

[0236] - Satellite processing time (e.g., processing time required to amplify and retransmit or decode and retransmit)

[0237] - K_mac value and / or K_mac error range

[0238] - Public TA and / or public TA error range

[0239] -Delay time between gateway and BS

[0240] - Information about the UE's mobility error (reported by the UE)

[0241] - Mobility information about NTN platforms (e.g., ephemeris information and / or satellite velocity information)

[0242] - Beam information about the NTN platform (e.g., SSB ID, CSI-RS ID, PRS ID, RSRP / SINR information about it, beam width / aiming information, TCI status information)

[0243] For example, the mobility information may be related to information about the position of a satellite at a specific time stamp (eg, information corrected based on a reference value) or information measured by the UE at a corresponding time.

[0244] In NTN, unlike TN, the links are divided into a feeder link between the RP and the satellite and a service link between the satellite and the UE. The RP is controlled based on the K_mac value of the BS so that the RP is located at a distance from the gateway that is equivalent to the difference between the UL and DL frame boundaries. Therefore, potential sources of error or timing delay during RTT calculation may include processing delays (e.g., amplify and forward or decode and forward) that occur when the satellite receives and transmits signals, errors in configuring the K_mac value between the gateway and the RP, and delays between the BS and the gNB. Although the BS is able to calculate the above error values ​​separately and send them to the LMF, the BS may send these error values ​​as a single representative error term / delay time to the LMF. For example, the BS may send a representative value of the feeder link delay to the LMF. Therefore, in NTN, the following steps are required for multi-RTT calculation: The RTT between the satellite and the UE may be calculated by subtracting twice the delay caused between the gateway and the RP (K_mac) and / or between the RP and the satellite (feeder link delay (or common TA)) from the gNB Rx-Tx time difference - UE Rx-Tx time difference. For more accurate calculations, each parameter value and / or delay value may be reported based on a specific measurement time. This is because in the case of LEO satellites, the satellites move at very high speeds, which may result in delay differences between UL and DL. For this purpose, the BS may also send time information related to each measurement or parameter value to the LMF. In multi-RTT operation, multiple measurements may be performed in the time domain. For example, the BS may send the following measurements to the LMF: Fig.15 The gNB Rx-Tx time difference and UE Rx-Tx time difference at time points t0, t1, and t2 are shown, along with the information listed in Proposal 1. The LMF then performs multi-RTT calculation based on the gNB Rx-Tx time difference, UE Rx-Tx time difference, and the information listed in Proposal 1. Subsequently, the LMF performs NW verification on the UE position obtained from the multi-RTT calculation.

[0245] Proposal 1-1

[0246] The UE may provide error information / delay information of RTT calculation to the LMF. The error information / delay information signaled by the UE may include some or all of the following.

[0247] -UE GNSS error range

[0248] -UE-specific TA calculated by the UE

[0249] - Timing error value at the UE side (e.g., measured DL timing drift / offset due to Doppler effect)

[0250] - Mobility information about the UE (e.g., speed, direction, travel time, etc.)

[0251] -Beam information about the UE (e.g., SRS ID, transmission power information, beam width / aiming information, etc.)

[0252] In Proposal 1-1, it is proposed to report the UE-specific TA value corresponding to the RTT between the UE and the satellite directly to the LMF. In this scenario, the UE-specific TA value calculated based on GNSS needs to obtain the trust of the NW. Therefore, the multi-RTT technology based on this method can be applied after the NW verifies the UE location information. In other words, it is proposed to calculate the RTT according to Proposal 1 in the initial access step or the step in which the UE first verifies the UE location information to the NW, and then calculate the RTT based on the UE-specific TA and / or timing error in subsequent steps. The BS can forward the value reported by the UE to the LMF (after recalculating / correcting the value). In the above proposal, UE mobility information is also provided to the LMF in order to reduce the error that may occur while the UE moves at the moment of measuring the RTT. Similar to Proposal 1, the UE can include the listed information in a single representative delay or timing error value on the UE side, and then report the single value to the LMF / BS.

[0253] In Proposal 1 and Proposal 1-1, assuming that ephemeris information is also reported to the LMF so that the LMF can obtain information about the satellite position, the parameter set (e.g., TACommon, TACommonDrift, and TACommonDriftVariation) used to calculate the common TA may also be signaled to the LMF. In addition, the BS or NW may indicate / configure a threshold as an error determination criterion to evaluate the error information in the above Proposal 1 and Proposal 1-1. The threshold may be configured only for the representative values ​​described in Proposal 1 and Proposal 1-1 above. Then, the UE / BS may report a value to the LMF based on the threshold only when there is an error.

[0254] In NTN, mobility information may be information about the position of a satellite at a specific time stamp (which may be information corrected based on a reference value) and reported together with information measured by the UE at the corresponding time.

[0255] In the beam information, the beam width can be fixed or changed by steering. From the perspective of the NTN, the direction in global coordinates can change, assuming a fixed position. In addition, from the perspective of the NTN, the satellite can change the beam pointing direction to ensure that the beam is sent to the same location on the ground.

[0256] Proposal 2

[0257] For multi-RTT operation based on a single satellite, the BS can instruct the UE to periodically / semi-periodically measure the UE Rx-Tx time difference results and report to the LMF. In addition, the BS can provide the LMF with information about which measurements are used to perform multi-RTT operation.

[0258] The purpose of the above-mentioned Proposal 2 is as follows. The UE needs to measure multiple UE Rx-Tx time differences based on a single satellite and report the multiple UE Rx-Tx time differences to the LMF, but due to the long RTT caused by the nature of NTN, it may be cumbersome for the BS to trigger the measurement and reporting of the UE Rx-Tx time difference at a specific time point. To solve this problem, the BS periodically / semi-periodically triggers the measurement and / or reporting of the UE Rx-Tx time difference. The BS may inform the LMF which measurements to use at a specific time point, or this information may rely on the gNB Tx-Rx time difference reported by the BS. In order to measure the UE Rx-Tx time difference, one or more measurement windows may be configured. Before the measurement window is valid, the UE may measure the UE Rx-Tx time difference according to a periodicity / offset predetermined or determined by the BS and report it to the LMF. Alternatively, the UE may consider the validity duration (window) configured by the NTN cell as a virtual measurement window to perform measurements, or the UE may only consider the values ​​within the specified window to be valid.

[0259] In the above proposal, for more flexible measurement, different IDs may be assigned to the DL-PRS and / or SRS used for positioning to measure the Rx-Tx time difference of each UE. In this case, multiple SRSs may be used for UL transmission based on different spatial relationships. In addition, a measurement window may be configured for each ID. Even for the same BWP / CC, the measurement window may be configured to overlap. The number of configurable windows may depend on the UE capability.

[0260] When the same ID is assigned to PRS and / or SRS for positioning for multiple measurements, the UE may report the maximum number of measurements that the UE can perform per ID as UE capabilities. The BS may instruct the UE to perform measurements based on the UE capabilities. In this case, the UE may accumulate multiple measurement values and report the accumulated measurement values to the LMF at once. These values may include DL-PRS / SRS ID for positioning, PRS RSRP, UE Rx-Tx time difference, etc. To reduce the payload, these values may be reported as differences based on a specific reference value (e.g., the first measurement value (T0 in Figure A)). When measuring the UE Rx-Tx time difference using one DL-PRS ID and / or SRS ID, there may be a timing overlap between PRS reception and SRS transmission. Therefore, in the case of using the same ID, the BS allocates resources to the UE to exclude the above scenario. When there is a timing overlap between PRS reception and SRS transmission, for example, when the next PRS is received before SRS transmission, if the UE capabilities are high, i.e., if the UE has sufficient processing time and / or sufficient buffer capacity, the UE may receive the PRS. However, if the processing time or buffer capacity is insufficient, the UE may not attempt PRS reception. For this reason, the UE may report information about the memory / buffer state of the UE to the BS. Alternatively, measurement gaps may be configured between measurement events (e.g., t0, t1, t2 in Figure A) to allow the UE to perform new measurements based on the DL-PRS transmitted after the measurement gap.

[0261] For UE Rx-Tx time difference measurement, as shown in Table 9, the following operations are defined in the NR specification.

[0262] [Table 9]

[0263]

[0264] In other words, the UE reports the time information about the measurement as a timestamp. In the case of cumulative reporting based on a single PRS ID, the timestamp information may contain multiple pieces of information. For example, when the UE reports N measurements, one PRS ID may be included together with N SFNs and / or N slot numbers. In another example, one PRS ID, one SFN, one slot number, and the time differences (in milliseconds / slots / symbols) between N-1 measurements may be reported to the LMF / BS. If multiple PRS IDs are used, the timestamp information may be reported to the LMF / BS as N independent pieces of information. Alternatively, these two methods may be combined as follows: M reports (where M < N) may be provided for N measurements. In this case, the M reports are associated with M PRS IDs.

[0265] In the above proposals, the term "NTN platform" may refer to satellites such as GEO satellites, MEO satellites, and LEO satellites, or mobile objects such as HAPs, unmanned aerial vehicles (UAVs), drones, and airplanes.

[0266] The term "base station (BS)" may cover objects involved in data transmission and reception with a UE. For example, a BS may be a concept including one or more transmission points (TPs), one or more transmission and reception points (TRPs), etc. The TP and / or TRP may include a panel, a transmission and reception unit, etc. of the BS. In addition, the term "TRP" may be replaced with a panel, an antenna array, a cell (e.g., a macro cell / small cell / micro cell, etc.), a TP, a BS (gNB, etc.), etc. As described above, the TRP may be distinguished based on information about a CORESET group (or CORESET pool) (e.g., an index, an ID). For example, when a UE is configured to transmit and receive with multiple TRPs (or cells), it may mean that multiple CORESET groups (or CORESET pools) are configured for one UE. The configuration of such a CORESET group (or CORESET pool) may be performed through high-layer signaling (e.g., RRC signaling, etc.).

[0267] Although the proposed methods can be implemented independently, some of the proposed methods can be combined (or merged) for implementation. In addition, it may be specified that information on whether to apply the proposed method (or information on rules related to the proposed method) needs to be sent from the BS to the UE in a predefined signal (e.g., a physical layer signal, a high layer signal, etc.). For example, the high layer may include at least one of the following functional layers: MAC, RLC, PDCP, RRC, and SDAP.

[0268] As an implementation example, regarding the UL transmission of the UE, the UE may receive NTN-related configuration information, UL data-related information, and / or UL channel-related information. Thereafter, the UE may receive DCI / control information regarding the transmission of UL data and / or UL channels. The DCI / control information may include scheduling information for the transmission of UL data / UL channels. The UE may transmit UL data / UL channels based on the scheduling information. The UE may perform the transmission of UL data / UL channels until the UE transmits all configured / indicated UL data / UL channels. When the UE transmits all UL data / UL channels, the UE may terminate the UL transmission process.

[0269] As an implementation example, regarding the DL reception of the UE, the UE may receive NTN-related configuration information, DL data-related information and / or DL ​​channel-related information. Thereafter, the UE may receive DCI / control information regarding the reception of the DL data and / or DL ​​channel. The DCI / control information may include scheduling information for the DL data / DL channel. The UE may receive the DL data / DL channel based on the scheduling information. The UE may perform reception of the DL data / DL channel until the UE receives all configured / indicated DL data / DL channels. When the UE receives all DL data / DL channels, the UE may determine whether feedback information for the received DL data / DL channels is required. If necessary, the UE may send HARQ-ACK feedback. If not required, the UE may terminate the reception process without sending HARQ-ACK feedback.

[0270] As an implementation example, regarding UL reception of the BS, the BS may send (to the UE) NTN-related configuration information, UL data-related information, and / or UL channel-related information. Thereafter, the BS may send (to the UE) DCI / control information regarding the transmission of UL data and / or UL channels. The DCI / control information may include scheduling information for the transmission of UL data / UL channels. The BS may receive (from the UE) UL data / UL channels sent based on the scheduling information. The BS may perform reception of UL data / UL channels until the BS receives all configured / indicated UL data / UL channels. When the BS receives all UL data / UL channels, the BS may terminate the UL reception process.

[0271] As an implementation example, regarding the DL transmission of the BS, the BS may send NTN-related configuration information, DL data-related information and / or DL ​​channel-related information (to the UE). Thereafter, the BS may send DCI / control information about the reception of DL data and / or DL ​​channels (to the UE). The DCI / control information may include scheduling information for the DL data / DL channels. The BS may send DL data / DL channels (to the UE) based on the scheduling information. The BS may perform the transmission of DL data / DL channels until the BS sends all configured / indicated DL data / DL channels. When the BS sends all DL data / DL channels, the BS may determine whether it is necessary to receive feedback information for the DL data / DL channels. If necessary, the BS may receive HARQ-ACK feedback. If not required, the BS may terminate the DL transmission process without receiving HARQ-ACK feedback.

[0272] As an implementation example, the UE may be configured with a default HARQ operation mode in a step prior to RRC connection / configuration. For example, if the cell to which the UE has accessed is indicated as an NTN cell via PBCH (MIB) or SIB, the UE may perceive that the default mode is set to HARQ disabled. For example, one of a HARQ disabled configuration or a HARQ enabled configuration may be indicated as the default operation mode via PBCH (MIB) or SIB (e.g., when the cell is indicated as an NTN cell).

[0273] As an implementation example, the UE may report information about UE capabilities related to the proposed method to the BS. For example, the UE capability information may include information about the number of times a channel (e.g., PDSCH) supported / recommended by the UE is repeated, information about the slot aggregation level, and / or information about the number of supported HARQ processes. For example, the UE capability information may be reported periodically / semi-persistently / aperiodically. The BS may configure / indicate the following operations considering the UE capability.

[0274] Fig.16 2 is a diagram for explaining the operation of a system supporting NTN according to an embodiment.

[0275] exist Fig.16 In this paper, we consider UE positioning that does not rely on GNSS signals (B). GNSS signals (B) are Figure 7 In the structure shown, RAT independent signals transmitted by satellites are not considered. In other words, RAT independent signals such as GNSS signals (B) are not considered to avoid blurring the main points of the description. In addition, Figure 7 The radio signal (A) sent by the reference source BS (gNB) is a RAT dependent signal. Figure 7 The reference source BS (gNB) is shown to send a radio signal (A) directly to the target device (i.e., UE). Fig.16 In the , signal transmission and reception between UE and gNB can be performed through NTN (satellite).

[0276] Reference Fig.16 , the LMF (e.g., location server) may exchange assistance data for positioning with the UE and / or BS (1605). The LMF may send the assistance data to the UE based on the LPP protocol. The BS may send the assistance data to the LMF based on the NRPPa protocol. As described above, the assistance data sent by the BS to the LMF may include public TA information.

[0277] The BS may provide the UE with a PRS configuration (1610) and transmit the PRS based on the PRS configuration (1615). The UE may transmit an SRS for positioning after receiving the PRS (1620). The PRS / SRS transmission / reception between the UE and the BS may be performed through NTN (satellite).

[0278] The UE may report measurement information including the UE Rx-Tx time difference based on PRS / SRS to the LMF through the LPP protocol (1625). The information sent by the UE to the LMF may include information about the DL timing drift. For example, the DL timing drift may be incorporated as part of the auxiliary data sent by the UE to the LMF. The DL timing drift is a value measured by the UE. Specifically, the UE may estimate the DL timing offset caused by Doppler on the service link associated with the UE Rx-Tx time difference measurement period.

[0279] The BS may also measure the gNB Rx-Tx time difference based on PRS / SRS and report the gNB Rx-Tx time difference to the LMF through the NRPPa protocol (1630). The gNB Rx-Tx time difference may be the gNB Rx-Tx time difference at the UL synchronization RP.

[0280] The LMF may calculate the UE's location based on measurement reports obtained from the UE and the BS (1630), and then provide the calculated UE location to the AMF (1635).

[0281] The AMF may verify the UE location received from the LMF (1640).

[0282] Fig.17 2 is a diagram for explaining the operation of the first device according to the embodiment.

[0283] Reference Fig.17 The first device may obtain TA information based on a first link between the non-terrestrial node of the NTN and the first device (A05). The TA information may include common TA information between the RP configured on the first link and the non-terrestrial node.

[0284] The first device may transmit assistance data for NTN-based UE positioning to the LMF node (A10). The first device may report common TA information to the LMF node through the assistance data.

[0285] The first device may measure a time difference between a UL reference signal and a DL reference signal (A15).

[0286] The first device may send a measurement report including information about the time difference to the LMF node (A20).

[0287] The non-terrestrial node may be a satellite and the first device may be a terrestrial BS.

[0288] The first link may be a feeder link between the satellite and the terrestrial BS.

[0289] The time difference between the UL reference signal and the DL reference signal (e.g., the gNB Rx-Tx time difference of NTN) can be the time difference between the PRS sent by the first device to the UE through the non-terrestrial node and the SRS received by the first device from the UE through the non-terrestrial node at the RP.

[0290] For NTN based UE positioning, information about the UE DL timing error may be provided to the LMF node.

[0291] The information about the UE DL timing error may include an estimate of the DL timing offset related to the Doppler effect.

[0292] Information about UE DL timing error may be measured by the target UE for NTN based UE positioning.

[0293] The information about the UE DL timing error may be related to a period of time during which the target UE measures a time difference between a UL reference signal and a DL reference signal.

[0294] NTN-based UE positioning can be performed independently of GNSS.

[0295] Fig.18 is a diagram for explaining the operation of the second device according to one embodiment.

[0296] Reference Fig.18 The second device may obtain TA information based on a second link between the non-terrestrial node of the NTN and the second device (B05). The TA information may include UE-specific TA information.

[0297] The second device may receive first assistance data for NTN-based UE positioning from the LMF node (B10).

[0298] The second device may measure a time difference between the UL reference signal and the DL reference signal (B15).

[0299] The second device may send a measurement report including information about the time difference and second assistance data to the LMF node (B20). The second device may report the timing error measured by the second device to the LMF node through the second assistance data.

[0300] The second device may be a UE. The second device may be a processing device that controls the UE.

[0301] The non-terrestrial node may be a satellite and the second device may be a UE.

[0302] The second link may be a serving link between the satellite and the UE.

[0303] The timing error measured by the second device may be a UE DL timing error measured by the UE.

[0304] The time difference between the UL reference signal and the DL reference signal (eg, UE Rx-Tx time difference of NTN) may be a difference between a timing at which the second device receives a PRS from the BS through a non-terrestrial node and a timing at which the second device sends an SRS to the BS through the non-terrestrial node.

[0305] The information about the UE DL timing error may include an estimate of the DL timing offset related to the Doppler effect.

[0306] The information about the UE DL timing error may be related to a period of time during which the UE measures a time difference between a UL reference signal and a DL reference signal.

[0307] NTN-based UE positioning can be performed independently of GNSS.

[0308] Fig.19 A communication system 1 applied to the present disclosure is shown.

[0309] Reference Fig.19 , the communication system 1 applied to the present disclosure includes a wireless device, a base station (BS), and a network. Herein, a wireless device refers to a device that performs communication using a radio access technology (RAT) (e.g., 5G new RAT (NR) or long term evolution (LTE)), and may be referred to as a communication / radio / 5G device. The wireless device may include, but is not limited to, a robot 100a, vehicles 100b-1 and 100b-2, an extended reality (XR) device 100c, a handheld device 100d, a home appliance 100e, an Internet of Things (IoT) device 100f, and an artificial intelligence (AI) device / server 400. For example, a vehicle may include a vehicle with a wireless communication function, an autonomous driving vehicle, and a vehicle capable of performing communication between vehicles. Herein, a vehicle may include an unmanned aerial vehicle (UAV) (e.g., a drone). XR devices may include augmented reality (AR) / virtual reality (VR) / mixed reality (MR) devices, and may be implemented in the form of a head mounted device (HMD), a head up display (HUD) installed in a vehicle, a television, a smart phone, a computer, a wearable device, a home appliance device, a digital sign, a vehicle, a robot, etc. Handheld devices may include smart phones, smart boards, wearable devices (e.g., smart watches or smart glasses), and computers (e.g., notebooks). Home appliances may include TVs, refrigerators, and washing machines. IoT devices may include sensors and smart meters. For example, a BS and a network may be implemented as wireless devices, and a specific wireless device 200a may operate as a BS / network node relative to other wireless devices.

[0310] The wireless devices 100a to 100f may be connected to the network 300 via the BS 200. The AI ​​technology may be applied to the wireless devices 100a to 100f, and the wireless devices 100a to 100f may be connected to the AI ​​server 400 via the network 300. The network 300 may be configured using a 3G network, a 4G (e.g., LTE) network, or a 5G (e.g., NR) network. Although the wireless devices 100a to 100f may communicate with each other via the BS 200 / network 300, the wireless devices 100a to 100f may perform direct communication (e.g., side link communication) with each other without passing through the BS / network. For example, vehicles 100b-1 and 100b-2 may perform direct communication (e.g., vehicle-to-vehicle (V2V) / vehicle-to-everything (V2X) communication). An IoT device (e.g., a sensor) may perform direct communication with other IoT devices (e.g., a sensor) or other wireless devices 100a to 100f.

[0311] Wireless communication / connection 150a, 150b or 150c may be established between wireless devices 100a to 100f / BS200 or BS200 / BS200. Herein, wireless communication / connection may be established through various RATs (e.g., 5G NR) such as uplink / downlink communication 150a, sidelink communication 150b (or D2D communication) or inter-BS communication (e.g., relay, integrated access backhaul (IAB)). The wireless device and the BS / wireless device may send / receive radio signals to / from each other through wireless communication / connection 150a and 150b. For example, wireless communication / connection 150a and 150b may send / receive signals through various physical channels. To this end, at least a portion of various configuration information for configuring processes for sending / receiving radio signals, various signal processing processes (e.g., channel coding / decoding, modulation / demodulation, and resource mapping / demapping), and resource allocation processes may be performed based on various proposals of the present disclosure.

[0312] Fig. 20 A wireless device suitable for use with the present disclosure is shown.

[0313] Reference Fig. 20 , the first wireless device 100 and the second wireless device 200 may transmit radio signals via various RATs (e.g., LTE and NR). Herein, {the first wireless device 100 and the second wireless device 200} may correspond to Fig.19 {wireless device 100x and BS 200} and / or {wireless device 100x and wireless device 100x}.

[0314] The first wireless device 100 may include one or more processors 102 and one or more memories 104, and further include one or more transceivers 106 and / or one or more antennas 108. The processor 102 may control the memory 104 and / or the transceiver 106, and may be configured to implement the description, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document. For example, the processor 102 may process the information in the memory 104 to generate first information / signals, and then transmit a radio signal including the first information / signals through the transceiver 106. The processor 102 may receive a radio signal including second information / signals through the transceiver 106, and then store information obtained by processing the second information / signals in the memory 104. The memory 104 may be connected to the processor 102, and may store various information related to the operation of the processor 102. For example, the memory 104 may store software codes including commands for executing part or all of the processes controlled by the processor 102 or for executing the description, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document. Herein, the processor 102 and the memory 104 may be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver 106 may be connected to the processor 102 and transmit and / or receive radio signals through one or more antennas 108. Each transceiver 106 may include a transmitter and / or a receiver. The transceiver 106 may be used interchangeably with a radio frequency (RF) unit. In an embodiment of the present disclosure, a wireless device may represent a communication modem / circuit / chip.

[0315] The second wireless device 200 may include one or more processors 202 and one or more memories 204, and further include one or more transceivers 206 and / or one or more antennas 208. The processor 202 may control the memory 204 and / or the transceiver 206, and may be configured to implement the description, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document. For example, the processor 202 may process the information in the memory 204 to generate third information / signals, and then transmit a radio signal including the third information / signals through the transceiver 206. The processor 202 may receive a radio signal including fourth information / signals through the transceiver 206, and then store information obtained by processing the fourth information / signals in the memory 204. The memory 204 may be connected to the processor 202, and may store various information related to the operation of the processor 202. For example, the memory 204 may store software codes including commands for executing part or all of the processes controlled by the processor 202 or for executing the description, functions, processes, proposals, methods, and / or operation flowcharts disclosed in this document. Herein, the processor 202 and the memory 204 may be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver 206 may be connected to the processor 202 and transmit and / or receive radio signals through one or more antennas 208. Each transceiver 206 may include a transmitter and / or a receiver. The transceiver 206 may be used interchangeably with an RF unit. In an embodiment of the present disclosure, a wireless device may represent a communication modem / circuit / chip.

[0316] In the following, the hardware elements of the wireless devices 100 and 200 will be described in more detail. One or more protocol layers may be implemented by (but not limited to) one or more processors 102 and 202. For example, one or more processors 102 and 202 may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, and SDAP). One or more processors 102 and 202 may generate one or more protocol data units (PDUs) and / or one or more service data units (SDUs) according to the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document. One or more processors 102 and 202 may generate messages, control information, data, or information according to the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document. One or more processors 102 and 202 may generate a signal (e.g., a baseband signal) including a PDU, SDU, message, control information, data, or information according to the description, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document, and provide the generated signal to one or more transceivers 106 and 206. One or more processors 102 and 202 may receive a signal (e.g., a baseband signal) from one or more transceivers 106 and 206 and obtain the PDU, SDU, message, control information, data, or information according to the description, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document.

[0317] One or more processors 102 and 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. One or more processors 102 and 202 may be implemented by hardware, firmware, software, or a combination thereof. As an example, one or more application specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field programmable gate arrays (FPGAs) may be included in one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operational flow charts disclosed in this document may be implemented using firmware or software, and the firmware or software may be configured to include modules, processes, or functions. Firmware or software configured to execute the descriptions, functions, processes, proposals, methods, and / or operational flow charts disclosed in this document may be included in one or more processors 102 and 202 or stored in one or more memories 104 and 204 to be driven by one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods and / or operational flow charts disclosed in this document may be implemented in the form of codes, commands and / or command sets using firmware or software.

[0318] One or more memories 104 and 204 may be connected to one or more processors 102 and 202 and store various types of data, signals, messages, information, programs, codes, instructions and / or commands. One or more memories 104 and 204 may be configured by read-only memory (ROM), random access memory (RAM), electrically erasable programmable read-only memory (EPROM), flash memory, hard disk drive, register, cache memory, computer-readable storage medium and / or a combination thereof. One or more memories 104 and 204 may be located inside and / or outside of one or more processors 102 and 202. One or more memories 104 and 204 may be connected to one or more processors 102 and 202 by various technologies such as wired or wireless connections.

[0319] One or more transceivers 106 and 206 may send user data, control information and / or radio signals / channels mentioned in the method and / or operation flow chart of this document to one or more other devices. One or more transceivers 106 and 206 may receive user data, control information and / or radio signals / channels mentioned in the description, function, process, proposal, method and / or operation flow chart disclosed in this document from one or more other devices. For example, one or more transceivers 106 and 206 may be connected to one or more processors 102 and 202 and send and receive radio signals. For example, one or more processors 102 and 202 may perform control so that one or more transceivers 106 and 206 may send user data, control information or radio signals to one or more other devices. One or more processors 102 and 202 may perform control so that one or more transceivers 106 and 206 may receive user data, control information or radio signals from one or more other devices. One or more transceivers 106 and 206 may be connected to one or more antennas 108 and 208, and one or more transceivers 106 and 206 may be configured to send and receive user data, control information and / or radio signals / channels mentioned in the description, functions, processes, proposals, methods and / or operation flow charts disclosed in this document through one or more antennas 108 and 208. In this document, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106 and 206 may convert received radio signals / channels, etc. from RF band signals to baseband signals so as to process received user data, control information, radio signals / channels, etc. using one or more processors 102 and 202. One or more transceivers 106 and 206 may convert user data, control information, radio signals / channels, etc. processed using one or more processors 102 and 202 from baseband signals to RF band signals. To this end, one or more of the transceivers 106 and 206 may include (analog) oscillators and / or filters.

[0320] Fig.21 Another example of a wireless device applicable to the present disclosure is shown. The wireless device can be used according to the usage / service (refer to Fig.19 ) are implemented in various forms.

[0321] Reference Fig.21 , the wireless devices 100 and 200 may correspond to Fig. 20The wireless devices 100 and 200 of the present invention may be configured by various elements, components, units / parts and / or modules. For example, each of the wireless devices 100 and 200 may include a communication unit 110, a control unit 120, a memory unit 130 and an additional component 140. The communication unit may include a communication circuit 112 and a transceiver 114. For example, the communication circuit 112 may include Fig. 20 One or more processors 102 and 202 and / or one or more memories 104 and 204. For example, the transceiver 114 may include Fig. 20 The control unit 120 is electrically connected to the communication unit 110, the memory 130, and the additional components 140, and controls the overall operation of the wireless device. For example, the control unit 120 may control the electrical / mechanical operation of the wireless device based on the program / code / command / information stored in the memory unit 130. The control unit 120 may send information stored in the memory unit 130 to the outside (e.g., other communication devices) via the communication unit 110 through a wireless / wired interface, or store information received from the outside (e.g., other communication devices) via the communication unit 110 in the memory unit 130 through a wireless / wired interface.

[0322] The additional components 140 may be configured differently depending on the type of wireless device. For example, the additional components 140 may include at least one of a power supply unit / battery, an input / output (I / O) unit, a drive unit, and a computing unit. The wireless device may be configured in the form of, but not limited to, a robot ( Fig.19 100a), vehicles ( Fig.19 100b-1 and 100b-2), XR devices ( Fig.19 100c), handheld device ( Fig.19 100d), household appliances ( Fig.19 100e), IoT devices ( Fig.19 100f), digital broadcasting terminal, holographic device, public safety device, MTC device, medical device, fintech device (or financial device), security device, climate / environmental device, AI server / device ( Fig.19 400), BS( Fig.19 200), network nodes, etc. The wireless device can be used in a mobile or fixed location according to the usage example / service.

[0323] exist Fig.21In the wireless devices 100 and 200, various elements, components, units / parts and / or modules in the wireless devices 100 and 200 may all be connected to each other through a wired interface, or at least a part thereof may be wirelessly connected through the communication unit 110. For example, in each of the wireless devices 100 and 200, the control unit 120 and the communication unit 110 may be wired, and the control unit 120 and the first unit (e.g., 130 and 140) may be wirelessly connected through the communication unit 110. The various elements, components, units / parts and / or modules within the wireless devices 100 and 200 may also include one or more elements. For example, the control unit 120 may be configured by a collection of one or more processors. As an example, the control unit 120 may be configured by a collection of a communication control processor, an application processor, an electronic control unit (ECU), a graphics processing unit and a memory control processor. As another example, the memory 130 may be configured by a random access memory (RAM), a dynamic RAM (DRAM), a read-only memory (ROM)), a flash memory, a volatile memory, a non-volatile memory and / or a combination thereof.

[0324] Fig. 22 A vehicle or an autonomous vehicle applied to the present disclosure is shown. The vehicle or the autonomous vehicle can be implemented by a mobile robot, a car, a train, a manned / unmanned aerial vehicle (AV), a ship, etc.

[0325] Reference Fig. 22 , the vehicle or autonomous driving vehicle 100 may include an antenna unit 108, a communication unit 110, a control unit 120, a drive unit 140a, a power supply unit 140b, a sensor unit 140c, and an autonomous driving unit 140d. The antenna unit 108 may be configured as a part of the communication unit 110. Blocks 110 / 130 / 140a to 140d correspond to Fig.21 Block 110 / 130 / 140.

[0326] The communication unit 110 may send and receive signals (e.g., data and control signals) to and from external devices such as other vehicles, BSs (e.g., gNBs and roadside units), and servers. The control unit 120 may perform various operations by controlling elements of the vehicle or autonomous vehicle 100. The control unit 120 may include an electronic control unit (ECU). The drive unit 140a may enable the vehicle or autonomous vehicle 100 to travel on a road. The drive unit 140a may include an engine, a motor, a power system, wheels, brakes, a steering device, etc. The power supply unit 140b may supply power to the vehicle or autonomous vehicle 100, and include a wired / wireless charging circuit, a battery, etc. The sensor unit 140c may obtain vehicle status, surrounding environment information, user information, etc. The sensor unit 140c may include an inertial measurement unit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor, a slope sensor, a weight sensor, a heading sensor, a position module, a vehicle forward / backward sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a depth sensor, an ultrasonic sensor, a lighting sensor, a pedal position sensor, etc. The autonomous driving unit 140d may implement a technology for maintaining a lane in which the vehicle is traveling, a technology for automatically adjusting a speed (e.g., adaptive cruise control), a technology for autonomously traveling along a determined path, a technology for traveling by automatically setting a path if a destination is set, and the like.

[0327] For example, the communication unit 110 may receive map data, traffic information data, etc. from an external server. The autonomous driving unit 140d may generate an autonomous driving path and a driving plan from the obtained data. The control unit 120 may control the drive unit 140a so that the vehicle or the autonomous driving vehicle 100 may move along the autonomous driving path according to the driving plan (e.g., speed / direction control). In the middle of autonomous driving, the communication unit 110 may aperiodically / periodically obtain the latest traffic information data from the external server and obtain surrounding traffic information data from neighboring vehicles. In the middle of autonomous driving, the sensor unit 140c may obtain vehicle status and / or surrounding environment information. The autonomous driving unit 140d may update the autonomous driving path and driving plan based on the newly obtained data / information. The communication unit 110 may transmit information about the vehicle position, autonomous driving path, and / or driving plan to an external server. The external server may predict traffic information data based on information collected from the vehicle or autonomous driving vehicle using AI technology, etc., and provide the predicted traffic information data to the vehicle or autonomous driving vehicle.

[0328] Fig.23 NTN suitable for the present disclosure is shown. For example, Fig.19 The network 300 may be configured as an NTN. In addition, the NTN may be used in the above-mentioned devices to perform the operations described herein.

[0329] NTN refers to a wireless network configured with a device that is not fixed on the ground (e.g., a satellite). A representative example of NTN is a satellite network. Based on NTN, network services with extended coverage and high reliability can be realized. For example, NTN can be configured independently or in combination with an existing terrestrial network to create a wireless communication system.

[0330] The use cases that can be provided in the NTN-based communication system can be divided into three categories. The "Service Continuity" category can be used to provide network connectivity in geographic areas where 5G services cannot be accessed through the wireless communication coverage of the terrestrial network. For example, satellite connectivity can be used for UEs associated with pedestrian users, mobile ground platforms (e.g., cars, coaches, trucks, trains), aerial platforms (e.g., commercial or private jets), or UEs on offshore platforms (e.g., offshore vessels). In the "Service Ubiquity" category, when the terrestrial network is unavailable (e.g., due to disasters, destruction, economic conditions, etc.), satellite connectivity can be used for the following purposes: IoT, public safety-related emergency networks, home access, etc. The "Service Scalability" category covers services with wide coverage based on satellite networks.

[0331] Reference Fig.23 , the NTN may include one or more satellites 410, one or more NTN gateways 420 capable of communicating with the satellites, and one or more UEs (and / or BSs) 430 capable of receiving mobile satellite services from the satellites. Fig.23 In the present disclosure, for simplicity, the description focuses on NTNs including satellites, but the scope of the present disclosure is not limited thereto. Therefore, NTNs may include not only satellites, but also aerial vehicles (covering tethered UAS (TUA), lighter-than-air UAS (LTA), heavier-than-air UAS (HTA), and all UASs that typically operate at altitudes between 8km and 50km, including HAPs).

[0332] Satellite 410 is a spacecraft equipped with a bent pipe payload or a regenerative payload telecommunication transmitter, and may be located in LEO, MEO, or GEO. NTN gateway 420 is an earth station or gateway present on the surface of the earth, and may provide sufficient RF power / sensitivity to access the satellite. NTN gateway corresponds to a transmission network layer (TNL) node. One or more UE (and / or BS) 430 may be a wireless device (100a to 100f) and / or BS200. In addition, one or more UE (and / or BS) may be implemented as a device. Wireless devices 100a to 100f may be connected to NTN via BS200 and / or satellite 410.

[0333] NTN may have i) links between satellites and UEs, ii) links between satellites, iii) links between satellites and NTN gateways. A service link refers to a radio link between a satellite and a UE. If there are multiple satellites, there may be inter-satellite links (ISLs) between satellites. A feeder link refers to a radio link between an NTN gateway and a satellite (or UAS platform). The gateway may be connected to a data network and may communicate with a satellite via a feeder link. A UE may communicate with a satellite via a service link.

[0334] For NTN operation scenarios, two scenarios based on transparent payload and regenerated payload can be considered. Fig.23 (a) shows an exemplary scenario based on transparent payload. In the scenario based on transparent payload, the signal repeated by the payload remains unchanged. The satellite 410 repeats the NR-Uu radio interface from the feeder link to the service link (or vice versa), and the satellite radio interface (SRI) on the feeder link is NR-Uu. The NTN gateway 420 supports all functions required to send signals on the NR-Uu interface. In addition, different transparent satellites can be connected to the same gNB on the ground. Fig.23 (b) shows an exemplary scenario based on a regenerative payload. In a scenario based on a regenerative payload, the satellite 410 may perform some or all of the functions of a traditional BS (e.g., gNB). In other words, the satellite 410 may perform some or all of frequency conversion / demodulation / decoding / modulation. For the service link between the UE and the satellite, the NR-Uu radio interface is used, and for the feeder link between the NTN gateway and the satellite, the SRI is used. The SRI corresponds to the transmission link between the NTN gateway and the satellite.

[0335] UE 430 can be connected to the 5G core network (5GCN) through both NTN-based NG-RAN and traditional cellular NG-RAN. Alternatively, the UE can be connected to the 5GCN via two or more NTNs (e.g., LEO NTN, GEO NTN, etc.).

[0336] Fig.24 A very small aperture terminal (VSAT) suitable for use in the present disclosure is shown.

[0337] VSAT 450 may refer to an antenna / device capable of bidirectional communication with an antenna (board) less than 3 meters. For example, the VSAT may be fixedly located on the ground, or may be fixedly mounted on a vehicle / vessel. NTN may be configured with a VSAT. Fig.24 VSAT is based on mesh topology ( Fig.24 (a)) or star topology ( Fig.24(b)) is configured in the form of. In the case of a mesh topology, each VSAT may be configured to communicate directly with another VSAT. On the other hand, in the case of a star topology, multiple VSATs may be connected via a hub, and communication between VSATs may be performed via the hub. For example, VSAT 450 may operate as an NTN gateway 420 and / or BS. For example, VSAT 450 may operate as a BS and / or IAB node on an IAB link described later. For example, NTN gateway 420 may be connected to satellite 410, satellite 410 may be connected to VSAT 450, and VSAT 450 may be connected to UE 430 to provide services. In this case, VSAT 450 may communicate with satellite 430 as an IAB mobile terminal (IAB-MT), and may serve UE 430 as an IAB distribution unit (IAB-DU). In addition, satellite 410 may operate as a parent node.

[0338] The above-mentioned embodiments correspond to the combination of elements and features of the present disclosure in a prescribed form. And, unless explicitly mentioned, each element or feature may be regarded as selective. Each element or feature may be implemented in a form that is not combined with other elements or features. In addition, the embodiments of the present disclosure can be implemented by partially combining elements and / or features together. The order of operations described for each embodiment of the present disclosure may be modified. Some configurations or features of an embodiment may be included in another embodiment, or may replace the corresponding configuration or features of another embodiment. And, the embodiment may be configured by combining claims that do not have a clear reference relationship in the attached claims, or may be included as a new claim by modification after submitting the application.

[0339] Those skilled in the art will appreciate that the present disclosure may be implemented in other specific forms other than those described herein without departing from the spirit and essential characteristics of the present disclosure. Therefore, the above-described embodiments should be interpreted as being illustrative in all respects, rather than restrictive. The scope of the present disclosure should be determined by the appended claims and their legal equivalents, rather than by the above description, and all changes falling within the meaning and equivalent scope of the appended claims are intended to be covered therein.

[0340] Industrial Applicability

[0341] The present disclosure is applicable to UE, BS or other devices in a wireless mobile communication system.

Claims

1. A method performed by a first device in a wireless communication system including a non-terrestrial network NTN, the method comprising the following steps: obtaining timing advance (TA) information based on a first link between a non-terrestrial node for the NTN and the first device; Sending auxiliary data for positioning of user equipment UE based on NTN to the location management function LMF node; measuring a time difference between an uplink reference signal and a downlink reference signal; as well as sending a measurement report including information about the time difference to the LMF node, The TA information includes common TA information between the reference point RP configured on the first link and the non-ground node, and Wherein, the first device reports the public TA information to the LMF node through the auxiliary data.

2. The method according to claim 1, wherein: The non-ground node is a satellite, Wherein, the first device is a ground base station, and The first link is a feeder link between the satellite and the ground base station.

3. The method according to claim 1, wherein: The time difference between the uplink reference signal and the downlink reference signal is a time difference between a sounding reference signal SRS and a positioning reference signal PRS at the RP, The PRS is sent by the first device to the UE via the non-terrestrial node, and The SRS is received by the first device from the UE via the non-ground node.

4. The method according to claim 1, wherein: For the NTN based UE positioning, information about the UE downlink timing error is provided to the LMF node.

5. The method according to claim 4, wherein: The information about the UE downlink timing error includes an estimate of a downlink timing offset related to the Doppler effect.

6. The method according to claim 4, wherein: The information about the UE downlink timing error is measured by a target UE for the NTN based UE positioning.

7. The method according to claim 6, wherein: The information about the UE downlink timing error is related to a time period during which the target UE measures the time difference between the uplink reference signal and the downlink reference signal.

8. The method according to claim 1, wherein: The NTN-based UE positioning is performed independently of the Global Navigation Satellite System GNSS. 9 . A processor-readable recording medium having recorded thereon a program for executing the method according to claim 1 .

10. A method performed by a second device in a wireless communication system including a non-terrestrial network NTN, the method comprising the following steps: obtaining timing advance (TA) information based on a second link between a non-terrestrial node for the NTN and the second device; receiving first assistance data for positioning of a user equipment UE based on the NTN from a location management function LMF node; measuring a time difference between an uplink reference signal and a downlink reference signal; as well as sending a measurement report including information about the time difference and second assistance data to the LMF node, Wherein, the TA information includes UE-specific TA information, and The second device reports the timing error measured by the second device to the LMF node through the second assistance data.

11. The method according to claim 10, wherein: The non-ground node is a satellite, The second device is a UE, wherein the second link is a service link between the satellite and the UE, and The timing error measured by the second device is a downlink timing error measured by the UE.

12. A first device in a wireless communication system including a non-terrestrial network (NTN), the first device comprising: a memory storing instructions; as well as a processor configured to perform operations by executing the instructions, The operation of the processor includes: obtaining timing advance (TA) information based on a first link between a non-terrestrial node for the NTN and the first device; Sending auxiliary data for positioning of user equipment UE based on NTN to the location management function LMF node; measuring a time difference between an uplink reference signal and a downlink reference signal; and sending a measurement report including information about the time difference to the LMF node, The TA information includes common TA information between the reference point RP configured on the first link and the non-ground node, and Wherein, the first device reports the public TA information to the LMF node through the auxiliary data.

13. The first device of claim 11, further comprising a transceiver, wherein the first device is a ground base station.

14. A second device in a wireless communication system including a non-terrestrial network (NTN), the second device comprising: a memory storing instructions; as well as a processor configured to perform operations by executing the instructions, The operation of the processor includes: obtaining timing advance (TA) information based on a second link between a non-terrestrial node for the NTN and the second device; receiving first assistance data for positioning of a user equipment UE based on the NTN from a location management function LMF node; measuring a time difference between an uplink reference signal and a downlink reference signal; and sending a measurement report including information about the time difference and second assistance data to the LMF node, Wherein, the TA information includes UE-specific TA information, and The second device reports the timing error measured by the second device to the LMF node through the second assistance data.

15. The second device according to claim 14, further comprising a transceiver, wherein the second device is a UE.

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