Method and apparatus for positioning in wireless communication system

Abstract

The present disclosure relates to a method of performing measurements for positioning. The method may include performing a first type of measurement for positioning including carrier phase measurement (CPM); performing a second type of measurement for positioning different from the first type of measurement; and reporting both the first type of measurement and the second type of measurement, and wherein the number of time instances associated with the second type of measurement may be equal to or greater than the number of time instances of the first type of measurement.

Description

Technical Field

[0001] The present disclosure relates to wireless communication systems, and more particularly to methods and apparatus for a positioning process including measurements for positioning. Background Art

[0002] Wireless access systems have been widely deployed to provide various types of communication services such as voice or data. Generally, a wireless access system is a multiple access system that supports communication of multiple users by sharing available system resources (bandwidth, transmission power, etc.) among them. For example, multiple access systems include code division multiple access (CDMA) systems, frequency division multiple access (FDMA) systems, time division multiple access (TDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, and single carrier frequency division multiple access (SC-FDMA) systems. Summary of the invention

[0003] Technical issues

[0004] The object of the present disclosure is to provide a method and apparatus for performing a positioning process efficiently and accurately.

[0005] Those skilled in the art will understand that the objectives that can be achieved by the present disclosure are not limited to what has been 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 for performing measurements for positioning by a user equipment (UE) in a wireless communication system may include: performing a first type of measurement for positioning including a carrier phase measurement (CPM); performing a second type of measurement for positioning that is different from the first type of measurement; and reporting both the first type of measurement and the second type of measurement, wherein the number of time instances associated with the second type of measurement may be equal to or greater than the number of time instances of the first type of measurement.

[0008] Preferably, the first type of measurement may be performed based on a single time instance and the second type of measurement may be performed based on a plurality of time instances.

[0009] Preferably, a single result obtained from the second type of measurements may be correlated with a plurality of results obtained from the first type of measurements.

[0010] Preferably, the plurality of results obtained from the first type of measurement may have a plurality of time stamp values ​​that are different from each other.

[0011] Preferably, the UE may send a UE capability report comprising at least one of: first information on whether the UE supports a first type of measurement; and second information on a number of time instances supported by the UE for a second type of measurement.

[0012] Preferably, the UE may receive third information on the number of time instances related to the second type of measurement.

[0013] Preferably, the third information may comprise a minimum number of time instances related to the second type of measurements.

[0014] Preferably, the UE may send the number of time instances related to the second type of measurement that the UE prefers.

[0015] Preferably, the first type of measurement and the second type of measurement may be reported in a single measurement report.

[0016] Preferably, a single measurement report may comprise the number of time instances relating to the second type of measurements.

[0017] Preferably, the single measurement report may include timestamp information for the first type of measurement.

[0018] Preferably, the timestamp information for the first type of measurement may indicate a time instance when the first type of measurement is performed.

[0019] Preferably, the second type of measurement may include at least one of a downlink-reference signal time difference (DL-RSTD) measurement, an uplink-relative time of arrival (UL-RTOA) or a receive-transmit time difference measurement.

[0020] According to another aspect of the present disclosure, a non-transitory medium storing instructions may be provided, the instructions causing a processor to execute the method.

[0021] According to another aspect of the present disclosure, a device for performing a method of performing measurement for positioning may be provided.

[0022] Beneficial Effects

[0023] According to the present disclosure, a positioning process can be efficiently and accurately performed in a wireless communication system.

[0024] Those skilled in the art will recognize that the effects that can be achieved through the present disclosure are not limited to the contents that have been specifically described above, and other advantages of the present disclosure will be more clearly understood based on the following detailed description in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1Physical channels in a 3rd Generation Partnership Project (3GPP) system as an exemplary wireless communication system and a general signal transmission method using the same are illustrated.

[0026] Figure 2 Figure 1 illustrates the architecture of a 5G system applicable to positioning of a UE connected to an NG-RAN or an E-UTRAN;

[0027] Figure 3 Illustration of the observed time difference of arrival (OTDOA) positioning method;

[0028] Figure 4 Figure 1 shows integer ambiguity resolution for four different (right) sets of ToA for the BS.

[0029] Figure 5 The illustration shows the outlier discarding by observing the minimization of MSE;

[0030] Figure 6 The figure shows the performance improvement due to the correct processing of the subsequent series of PRS frames;

[0031] Figure 7 Figure 1 illustrates the message passing during CP positioning;

[0032] Figure 8 FIGURE 1 illustrates UE positioning measurement in an embodiment of the present disclosure;

[0033] Fig. 9 A method of performing measurements for positioning according to an embodiment of the present disclosure is illustrated;

[0034] Fig.10 An exemplary communication system to which the present disclosure is applied is illustrated.

[0035] Fig.11 An exemplary wireless device applicable to the present disclosure is shown. DETAILED DESCRIPTION

[0036] The following technologies can be used in various wireless access systems, such as code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA), etc. 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, Evolved UTRA (E-UTRA), etc. 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 (LTE-A) is an evolution of 3GPP LTE. 3GPP New Radio or New Radio Access Technology (NR) is an evolved version of 3GPP LTE / LTE-A.

[0037] As more and more communication devices require greater communication capacity, the demand for enhanced mobile broadband communications relative to legacy radio access technologies (RATs) has emerged. Massive machine type communications (MTC), which can provide various services for multiple interconnected devices and things anytime and anywhere, is one of the important issues that need to be addressed in the next generation of communications. The design of communication systems that take into account services that are sensitive to reliability and latency is also under discussion. Therefore, the introduction of next-generation radio access technologies (RATs) for enhanced mobile broadband communications (eMBB), massive MTC (mMTC), and ultra-reliable and low-latency communications (URLLC) is under discussion. For convenience, this technology is referred to as NR or new RAT in this disclosure.

[0038] Although the following description is given in the context of a 3GPP communication system (e.g., NR) for the sake of clarity, the technical spirit of the present disclosure is not limited to the 3GPP communication system. For the background technology, terms and abbreviations used in the present disclosure, please refer to the technical specifications (e.g., 3GPP TS 38.211, 38.212, 38.213, 38.214, 38.300, 38.331, etc.) released before the present disclosure.

[0039] In a wireless access system, a user equipment (UE) receives information from a base station (BS) on DL and transmits information to the BS on UL. The information transmitted and received between the UE and the BS includes general data and various types of control information. There are many physical channels depending on the type / purpose of the information transmitted and received between the BS and the UE.

[0040] Figure 1 The figure illustrates physical channels in a 3GPP system and a general signal transmission method using the physical channels.

[0041] When the UE is powered on or enters a new cell, the UE performs an initial cell search (S11). The initial cell search involves the acquisition of synchronization with the BS. For this purpose, 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 synchronizes its timing with the BS and acquires information such as a cell identifier (ID) based on the PSS / SSS. In addition, the UE can acquire information broadcast in the cell by receiving the PBCH from the BS. During the initial cell search, the UE can also monitor the DL channel status by receiving a downlink reference signal (DL RS).

[0042] After the initial cell search, the UE may acquire more detailed system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) corresponding to the PDCCH (S12).

[0043] Subsequently, in order to complete the connection to the BS, the UE may perform a random access procedure with the BS (S13 to S16). Specifically, the UE may send a preamble on a physical random access channel (PRACH) (S13), and may receive a PDCCH and receive a random access response (RAR) for the preamble on a PDSCH corresponding to the PDCCH (S14). The UE may then send a physical uplink shared channel (PUSCH) by using the scheduling information in the RAR (S15), and perform a contention resolution procedure including receiving a PDCCH and a PDSCH signal corresponding to the PDCCH (S16).

[0044] When the random access procedure is performed in two steps, steps S13 and S15 may be performed as one step (wherein message A is transmitted by the UE), and steps S14 and S16 may be performed as one step (wherein message B is transmitted by the BS).

[0045] After the above process, in the general UL / DL signal transmission process, the UE may receive PDCCH and / or PDSCH from the BS (S17), and send a physical uplink shared channel (PUSCH) and / or a physical uplink control channel (PUCCH) to the BS (S18). The control information sent by the UE to the BS is generally referred to as uplink control information (UCI). UCI includes hybrid automatic repeat and request acknowledgment / negative acknowledgment (HARQ-ACK / NACK), scheduling request (SR), channel state information (CSI), etc. CSI includes channel quality indicator (CQI), precoding matrix index (PMI), rank indication (RI), etc. Typically, UCI is sent on the PUCCH. However, if control information and data should be sent at the same time, control information and data may be sent on the PUSCH. In addition, upon receiving a request / command from the network, the UE may send UCI on the PUSCH aperiodically.

[0046] The UE may perform a network access procedure to perform the described / proposed procedure and / or method. For example, the UE may receive and store system information and configuration information required to perform the described / proposed procedure and / or method during network (e.g., BS) access. The configuration information required for the present disclosure may be received via higher layer signaling (e.g., radio resource control (RRC) signaling, medium access control (MAC) signaling, etc.).

[0047] position

[0048] 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 by a client (e.g., an application) associated with the UE and reported to the client. Location information may also be requested by a client within or connected to a core network. Location information may be reported in a standard format such as a format for cell-based or geographic coordinates together with an estimated error of the UE's position and velocity and / or a positioning method used for positioning.

[0049] Figure 2 Illustration of the architecture of a 5G system applicable to positioning of UEs connected to NG-RAN or E-UTRAN.

[0050] refer to Figure 2, the AMF may receive a request for location services associated with a specific target UE from another entity such as a Gateway Mobile Location Center (GMLC), or the AMF itself decides to initiate location services on behalf of a specific target UE. The AMF then sends the request for location services to a Location Management Function (LMF). Upon receiving the request for location services, the LMF may process the request for location services and then return a processing result including the estimated position of the UE to the AMF. In the event that location services are requested by an entity other than the AMF, such as a GMLC, the AMF may send the processing result received from the LMF to this entity.

[0051] Next-generation evolved NB (ng-eNB) and gNB are network elements of NG-RAN that can provide measurements for positioning. ng-eNB and gNB can measure the radio signals for the target UE and send the measurement values ​​to the LMF. ng-eNB can control several TPs, such as remote radio heads, or PRS-only TPs to support the PRS-based beacon system for E-UTRA.

[0052] The LMF is connected to an Enhanced Serving Mobile Location Center (E-SMLC), which enables the LMF to access E-UTRAN. For example, the E-SMLC can enable the LMF to support OTDOA, which is one of the positioning methods of E-UTRAN, using DL measurements obtained by the target UE through signals sent by eNBs and / or PRS-only TPs in E-UTRAN.

[0053] The LMF may be connected to a SUPL Location Platform (SLP). The LMF may support and manage different location services for the target UE. The LMF may interact with a serving ng-eNB or serving gNB for the target UE in order to obtain location measurements for the UE. For positioning of the target UE, the LMF may determine positioning methods based on the location service (LCS) client type, required quality of service (QoS), UE positioning capabilities, gNB positioning capabilities, and ng-eNB positioning capabilities, and then apply these positioning methods to the serving gNB and / or serving ng-eNB. The LMF may determine additional information such as the location estimate accuracy and velocity of the target UE. The SLP is the secure user plane location (SUPL) entity responsible for positioning over the user plane.

[0054] The UE can measure its position using the DL RS sent by the NG-RAN and the E-UTRAN. The DL RS sent by the NG-RAN and the E-UTRAN to the UE may include SS / PBCH blocks, CSI-RS and / or PRS. Which DL RS is used to measure the position of the UE may conform to the configuration of the LMF / E-SMLC / ng-eNB / E-UTRAN, etc. The position of the UE may be measured using different global navigation satellite systems (GNSS), ground beacon systems (TBS), WLAN access points, Bluetooth beacons, and sensors (e.g., air pressure sensors) installed in the UE through a RAT-independent scheme. The UE may also include an LCS application or access the LCS application through communication with a network accessed thereby or through another application included therein. The LCS application may include measurement and calculation functions required to determine the position of the UE. For example, the UE may include an independent positioning function, such as a global positioning system (GPS), and report its position, independent of NG-RAN transmission. This independently obtained positioning information may be used as auxiliary information for positioning information obtained from the network.

[0055] 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 of the positioning methods may be used for UE positioning, two or more positioning methods may be used for UE positioning.

[0056] Figure 3 is a diagram illustrating the observed time difference of arrival (OTDOA) positioning method;

[0057] The OTDOA positioning method uses the time measured by the UE for DL ​​signals received 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 signal. The UE's position can be determined based on such measurement results and the geographic coordinates of neighboring TPs.

[0058] A UE connected to a gNB may request a measurement gap to perform OTDOA measurements from a TP. If the UE does not know the SFN of at least one TP in the OTDOA assistance data, the UE may use the autonomous gap to obtain the SFN of the OTDOA reference cell before requesting a measurement gap for performing reference signal time difference (RSTD) measurements.

[0059] 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 closest to the subframe received from the measurement cell. The reference cell may be selected by the UE.

[0060] For accurate OTDOA measurement, it is necessary to measure the time of arrival (ToA) of signals received from three or more geographically distributed TPs or BSs. For example, the ToA for each of TP 1, TP 2, and TP 3 can be measured, and the RSTD for TP 1 and TP 2, the RSTD for TP 2 and TP 3, and the RSTD for TP 3 and TP 1 can be calculated based on the three ToA values. A geometric hyperbola is determined based on the calculated RSTD values, and the point where the curves of the hyperbola intersect can be estimated as the UE's position. In this case, accuracy and / or uncertainty for each ToA measurement may occur, and the estimated position of the UE may be referred to as a specific range based on the measurement uncertainty.

[0061] Carrier Phase Positioning (CPP)

[0062] The following documents are incorporated by reference:

[0063] [1] Intel, “Revised SID for Extended and Improved NR Positioning Research,” RP-213588, Electronic Conference, December 6-17, 2021

[0064] [2] RAN1 Chair’s Notes, RAN1 #109-e, electronic meeting, May 9-20, 2022

[0065] [3] LGE, “Discussion on OFDM-based carrier phase measurement in NR”, R1-2207710, Toulouse, France, August 22-26, 2022

[0066] [4] Han Dun, Christian CJM Tiberius, and Gerard JM Janssen, “Localization in Multipath Channels Using OFDM Signals with Carrier Phase Tracking,” IEEE Access, vol. 8, pp. 13011-13028, January 2020

[0067] 5G NR continues its expansion towards enriching its functionality with new areas and use cases. Positioning, location management functionality is a very useful addition to any communication system and its development is still continuing within the specification. Starting from the simplest cell / sector based location in 2G / 3G systems, the positioning accuracy has increased significantly in the LTE version. The scalable architecture of 5G allows setting more challenging tasks for positioning and considering scenarios that may require millimeter-level accuracy. One of the examples of such scenarios / use models is an indoor factory, where 5G-NR based sensors may help to track the movement of containers and parts. Robotics and manufacturing applications require extremely precise positioning that cannot be achieved through traditional means.

[0068] Using traditional correlation-based positioning methods places minimal requirements on the TX and RX RF chains and transceiver synchronization / interoperation. For such methods, accuracy depends heavily on the signal bandwidth and is therefore limited by the amount of available resources.

[0069] In this case, sub-centimeter and millimeter positioning accuracy can only be achieved at higher FR2 frequencies when more bandwidth can be allocated for positioning purposes. However, for FR1 frequencies below 6 GHz, the total bandwidth and positioning accuracy using baseband correlation and CIR estimation methods are limited.

[0070] One of the promising methods for high-precision positioning is carrier phase positioning (CPP) based on carrier phase measurement (CPM). For such methods, the accuracy depends mainly on the carrier phase frequency, which can be much larger than the signal BW.

[0071] However, the ability to estimate and track the signal carrier phase places stringent requirements on the stability of the generator and the necessity to perform TX / RX chain calibration and synchronization. Various differential and double differential approaches can be used to address the aforementioned difficulties.

[0072] Even in the case of perfect TX and RX phase synchronization, there is a fundamental problem of phase periodicity - exact knowledge of the signal phase only gives us the fractional part of the wavelength range measurement, while the integer part cannot be obtained from phase measurements alone. This is a well-known integer ambiguity resolution (IAR) problem. Integer ambiguity resolution has been successfully implemented in GPS systems and is also being considered for CPM positioning in OFDM systems [4]. Typical solutions that help resolve integer ambiguities in modern positioning communication systems include:

[0073] - Use several (three or more) carriers

[0074] - Use of several reference points (satellites) for double-difference and TDoA positioning; and / or

[0075] -Use a constant signal that allows object tracking

[0076] For carrier phase positioning systems based on the 5G NR framework, using only multiple carriers for positioning is highly undesirable and is therefore not considered. At the same time, packet-based network services, with multiple users sending data as the primary task and positioning as a secondary feature, do not enable a constant flow of dedicated positioning signals. Due to service priorities and system load, regular distance estimate updates may not be available for 5G NR systems.

[0077] Therefore, for 5G NR CPP, we have to come up with a method that allows reliable IAR based on a single carrier in packet-based mode, based on single or multiple subsequent observations (multiple samples / instances).

[0078] Consider the ToA geometry as the TRP coordinates TRP from a subset of M base stations m xyz Some functions of and the measured distance between the selected UE and the mth TRP.

[0079] [Equation 1]

[0080]

[0081] Equation 1 can be used to obtain a coarse ToA position estimate by employing a suboptimal set of stations, as described in the previous section.

[0082] With carrier phase distance measurements, there can be a high accuracy estimate of the fractional wavelength portion of the measured distance. The carrier phase estimate of the total distance will consist of the integer N and the fractional portion Δ, as shown in Equation 2.

[0083] [Equation 2]

[0084]

[0085] Using the baseline coarse distance measure, an initial guess about the integer ambiguity can be expressed as Equation 3.

[0086] [Equation 3]

[0087]

[0088] However, this initial guess may differ from the actual value N by an amount defined by the accuracy of the underlying distance measurement algorithm. For simplicity, a 95-99% confidence interval for the distance estimate d can be considered, which can be expressed in wavelengths. For example, for a good estimate of 100 MHz, the distance value may be within three wavelengths (N=3) of the initial rough guess. Denoting this integer error value as K, the setting can be as follows:

[0089] [Equation 4]

[0090]

[0091] With such a preparation, a point cloud in 3D space can be obtained, which corresponds to the solution of equation 1 for all possible N values:

[0092] [Equation 5]

[0093]

[0094] Since, for each TRP and corresponding distance measurement d, the search should be performed independently, the total number of points in the point cloud should be equal to (2K+1)M.

[0095] Equation 5 provides a point cloud for each possible integer number of wavelengths per measured distance. The true position lies among them, but a single point cloud is not sufficient to resolve the ambiguity. Considering single-group measurements and the impossibility of using different time observations, other sets of BSs can be used to generate other point clouds. Finding the common point of all clouds can provide a solution to the integer ambiguities (see Figure 4 ). Additionally, other constraints and cost functions can be employed to select real points in the cloud.

[0096] The simulation results show that for a typical CPP test scenario, an indoor factory (InF) ​​may give a reliable IAR only for a relatively large signal bandwidth (around 100MHz) with a single observation approach. In the case of such a BW, the initial rough guess is already quite accurate and the IAR algorithm works fine.

[0097] However, for smaller signal BW, around 20-50MHz, a single measurement is not sufficient to achieve the target accuracy and even 90% reliability of IAR cannot be achieved. Therefore, multiple observation processing should be involved and multiple subsequent PRS should be sent.

[0098] The processing of multiple observations may include the following steps:

[0099] - Increase the accuracy of the coarse baseband estimate (Equation 1)

[0100] - Increase IAR resolution accuracy by discarding IAR outliers using MSE minimization techniques (see Figure 5 )

[0101] The application of these two techniques can significantly increase the IAR reliability of smaller BW signals.

[0102] Figure 6 The simulation results in show the performance improvement due to the correct processing of subsequent series of PRS frames with a period of 10ms.

[0103] It can be seen that for (a) 20 MHz, the correct IAR probability is doubled, while for (b) 50 MHz, the important 90% CDF level percentile can be achieved by the proposed processing.

[0104] According to an embodiment of the present disclosure, a method for combining multiple observations may be provided for carrier phase positioning in a 5G NR system.

[0105] Meanwhile, the existing 5G standard already has a mechanism for subsequent PRS transmissions with a given number of repetitions (dl-PRS-ResourceRepetitionFactor-r16) and duration between repetitions (dl-PRS-ResourceTimeGap-r16) information elements. Here, the repetition mechanism included in the existing 5G standard is introduced to improve SINR and accuracy in extremely poor channel conditions and long distances. However, this repetition mechanism is usually not triggered for typical good cases when CPP is possible.

[0106] Therefore, in order to ensure PRS repetition transmission even at good SNR, the TRP must be informed of the CPP related functions (LMF, Location Management Function) of the network. Therefore, specific messages regarding repetition sequence handling should be introduced in CPP related messaging (see Figure 7 ).

[0107] (1) Notes

[0108] As mentioned above,

[0109] - Using multiple observations can improve TDoA / ToA performance

[0110] - Higher TDoA / ToA accuracy can be expected as more observations are used.

[0111] - Improved TDoA / ToA accuracy can help increase integer value estimates

[0112] - Therefore, CPP accuracy can be significantly improved, especially for smaller BW sizes.

[0113] - In contrast, it is difficult to improve phase measurement accuracy by averaging multiple observations because of phase variations due to UE mobility

[0114] - Therefore, a single observation should be used to measure the phase value

[0115] (2) Background

[0116] In the existing 5G standards:

[0117] - Up to 4 observations can be used for TDoA / ToA measurements

[0118] - A "timestamp" can be reported together with the positioning measurement (eg, TDoA / ToA) to inform the LMF about the time when the UE performed the positioning measurement.

[0119] - The timestamp is the frame / slot index where the UE measured the PRS. Even if multiple observations are used for measurement, a single timestamp is reported and it depends on the selected UE

[0120] -Assistance data can be used to assist LMF / gNB / UE in positioning related operations. For example, LMF can use it to recommend to the UE an appropriate number of observations for positioning measurements.

[0121] - Capability signaling can be used to inform the gNB / LMF of the capabilities of a specific UE operation. Based on the reported UE capabilities, the LMF / gNB can determine which functions the UE can utilize and their associated restrictions (e.g., the number of observations the UE can be used for measurements)

[0122] (3) Proposal

[0123] Consider (1) remarks and (2) background (given that (1) enhances existing 5G standards):

[0124] - When the UE reports CPM together with OPM (other positioning measurements) (e.g., DL-RSTD, UL-RTOA, or UE / TRP Rx-Tx time difference), M ≥ 1 samples (instances) can be used for OPM and N = 1 samples (instances) can be used for CPM.

[0125] - The UE may report to the LMF / gNB the UE's capability to support CPP and is expected to be configured with N=1 by default.

[0126] -The UE may report to the LMF / gNB the UE's capability to support measurements based on measuring M samples (or instances) of the DL-PRS resource set.

[0127] -LMF can indicate to the UE / gNB the minimum M value required for OPM measurement

[0128] - The UE may provide assistance data containing the preferred M value to the LMF

[0129] -LMF can provide assistance data including M value suggestions to UE / gNB

[0130] -The UE / gNB may report the actual M value used to measure OPM together with the positioning measurement in the positioning measurement report.

[0131] - When the UE reports CPM together with OPM, a timestamp can be reported in the same measurement report, where the timestamp represents the time instance at which the UE measures the CPM.

[0132] In NR Release 18 positioning, support for UE reporting CPM (carrier phase measurement) as well as OPM (other positioning measurements; for example, RSTD, RTOA or Rx-Tx time difference) is considered for CPP (carrier phase based positioning).

[0133] As described above, OPM can be used to resolve integer ambiguity problems and the precise UE position can be estimated via CPM.

[0134] Based on the evaluation results, it is observed that the higher the OPM accuracy, the higher the CPP accuracy.

[0135] Furthermore, as more samples are used in the measurement, higher OPM accuracy can be achieved.

[0136] In NR positioning, OPM is obtained using M = 4 samples as the baseline method.

[0137] In most positioning measurements, multiple samples usually guarantee high accuracy (e.g., time-domain based positioning methods)

[0138] In contrast, since the phase varies due to UE mobility, it is difficult to improve the phase measurement accuracy by averaging multiple observations.

[0139] Furthermore, in order to perform the double-differentiation technique that helps to eliminate the TX / RX initial phase error component, the location server may need to have accurate knowledge about the time instance at which the CPM is performed.

[0140] Therefore, a CPM measurement with M=4 samples, e.g., averaging the estimated phase value over 4 time instances, may not be appropriate in a CPM report.

[0141] From these perspectives, the positioning measurement report method and its related processes are proposed as follows:

[0142] When the Rx node reports CPM together with OPM (e.g., DL-RSTD, UL-RTOA, or UE / TRP Rx-Tx time difference), M ≥ 1 samples (instances) are used for OPM and N = 1 samples (instances) are used for CPM.

[0143] - For example, the UE may report a DL-RSTD measurement obtained by averaging 4 samples with different time instances and a CPM obtained by 1 sample of the time instance.

[0144] - For example, the UE may report the Rx-Tx time difference measurement obtained by averaging 4 samples with different time instances and the CPM obtained by 1 sample of the time instance.

[0145] - For example, the gNB may report UL-RTOA measurements obtained by averaging 4 samples with different time instances and CPM obtained with 1 sample of the time instance.

[0146] - For example, the gNB may report the Rx-Tx time difference measurement obtained by averaging 4 samples with different time instances and the CPM obtained by 1 sample of the time instance.

[0147] The Rx node may report multiple positioning measurement pairs in the positioning measurement report, and each positioning measurement pair includes a single OPM for a TRP (or RS resource) and a single associated CPM

[0148] The Rx node may report multiple positioning measurement pairs in the positioning measurement report, and each positioning measurement pair includes a single OPM for a TRP (or RS resource) and multiple associated CPMs.

[0149] - Measure each CPM within a positioning measurement pair at different time instances

[0150] When the Rx node reports CPM together with OPM, a timestamp can be reported in each positioning measurement pair, wherein the timestamp indicates a time instance when the Rx node measures CPM.

[0151] - When a positioning measurement pair contains a single CPM, report a single timestamp for the CPM

[0152] -When a positioning measurement pair contains multiple CPMs, the timestamp corresponding to each CPM can be reported

[0153] To support the proposed method, the UE may report the capabilities supported by the CPP.

[0154] To support the proposed method, the UE may report the supported capability of the size of M, where M is the number of samples that can support OPM. To obtain higher accuracy than the traditional method, M>4 may be supported.

[0155] To support the proposed method, the location server can configure the Rx node with an M value. In this case, the Rx node uses M sample observations to measure OPM, while the Rx node uses one sample observation to measure CPM.

[0156] To support the proposed method, the location server can configure the minimum M value that the Rx node should consider as the minimum value. In this case, the Rx node uses M or more sample observations to measure OPM, while the Rx node uses one sample observation to measure CPM.

[0157] In addition to the capability report, the UE may also request a preferred M value from the location server via assistance data.

[0158] In addition to configuration, the location server can also make M value recommendations to the gNB / UE via assistance data.

[0159] If M is determined by the Rx node, the Rx node may be required to report the M value used for the measurement in the report.

[0160] The proposed method is able to improve the CPP accuracy performance.

[0161] The proposed method may be beneficial when the BW size used for positioning reference signals is limited. For example, when the proposed method is applied, the CPP accuracy of RedCap UEs can be improved (ie, a maximum of 20 MHz is allowed in FR1 range).

[0162] Figure 8 An example of the proposed method is shown.

[0163] Figure 8 (a) shows an example when a positioning measurement pair includes a single OPM and a single associated CPM for a TRP (or RS resource). In this example, 4 time instances are used to measure the OPM and one time instance is used for the associated CPM. In addition, the timestamp of the positioning measurement pair is determined by the time instance of the CPM.

[0164] Figure 8 (b) shows an example when a positioning measurement pair includes a single OPM and multiple associated CPMs for a TRP (or RS resource). In this example, 4 time instances are used to measure the OPM, and one time instance is used for each associated CPM. In addition, the time instance of each CPM is used to determine each timestamp.

[0165] Fig. 9 A method of performing measurement for positioning according to an embodiment of the present disclosure is illustrated.

[0166] refer to Fig. 9 , the UE may perform different types of measurements for positioning (905). For example, the UE may perform a first type of measurement for positioning including a carrier phase measurement (CPM) and a second type of measurement for positioning different from the first type of measurement. Preferably, the number of time instances associated with the second type of measurement may be equal to or greater than the number of the first type of measurement.

[0167] The UE may report different types of measurements for positioning (910). For example, the UE may report both first type measurements and second type measurements.

[0168] Preferably, the first type of measurement may be performed based on a single time instance and the second type of measurement may be performed based on a plurality of time instances.

[0169] Preferably, a single result obtained from the second type of measurement may be associated with multiple results obtained from the first type of measurement. Preferably, the multiple results obtained from the first type of measurement may have multiple timestamp values ​​that are different from each other (e.g., Figure 8 (b)).

[0170] Preferably, the UE may send a UE capability report, the UE capability report comprising at least one of: first information on whether the UE supports the first type of measurement; and second information on the number of time instances supported by the UE for the second type of measurement.

[0171] Preferably, the UE may receive third information on the number of time instances related to the second type of measurement.

[0172] Preferably, the third information may comprise a minimum number of time instances related to the second type of measurements.

[0173] Preferably, the UE may send the number of time instances related to the second type of measurement that the UE prefers.

[0174] Preferably, the first type of measurements and the second type of measurements may be included in a single measurement report.

[0175] Preferably, a single measurement report may comprise the number of time instances relating to the second type of measurements.

[0176] Preferably, the single measurement report may include timestamp information for the first type of measurement.

[0177] Preferably, the timestamp information for the first type of measurement may indicate a time instance when the first type of measurement is performed.

[0178] Preferably, the second type of measurement may include at least one of a downlink reference signal time difference (DL-RSTD) measurement, an uplink relative time of arrival (UL-RTOA) or a receive-transmit time difference measurement.

[0179] According to another aspect of the present disclosure, a non-transitory medium storing instructions for causing a processor to execute the method may be provided.

[0180] According to another aspect of the present disclosure, a device for performing a method of performing measurement for positioning may be provided.

[0181] Fig.10 The diagram illustrates a communication system 1 that can be applied to the present disclosure.

[0182] refer to Fig.10 , the communication system 1 applied to the present disclosure includes a wireless device, a BS, and a network. The wireless device is a device that performs communication using a radio access technology (RAT) (e.g., 5G NR (or new RAT) or LTE), also 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 IoT device 100f, 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 vehicle-to-vehicle (V2V) communication. Here, the vehicle may include an unmanned aerial vehicle (UAV) (e.g., a drone). The XR device may include an augmented reality (AR) / virtual reality (VR) / mixed reality (MR) device, and may be implemented in the following forms: a head mounted device (HMD), a head up display (HUD) installed in a vehicle, a television (TV), a smartphone, a computer, a wearable device, a home appliance, a digital signage, a vehicle, a robot, and the like. Handheld devices may include smart phones, smart tablets, wearable devices (e.g., smart watches or smart glasses), and computers (e.g., laptops). Home appliances may include televisions, refrigerators, washing machines, etc. IoT devices may include sensors, smart meters, etc. For example, the BS and the network may be implemented as wireless devices, and a specific wireless device 200a may operate as a BS / network node for other wireless devices.

[0183] The wireless devices 100a to 100f may be connected to the network 300 via the BS 200. 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., sidelink communication) with each other without intervention of the BS / network. For example, the vehicles 100b-1 and 100b-2 may perform direct communication (e.g., 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.

[0184] Wireless communication / connection 150a, 150b, and 150c may be established between wireless devices 100a to 100f / BS 200 and between BSs 200. Here, wireless communication / connection may be established through various RATs (e.g., 5G NR) such as UL / DL communication 150a, sidelink communication 150b (or D2D communication), or inter-BS communication 150c (e.g., relay or integrated access backhaul (IAB)). Wireless signals may be sent and received between wireless devices, between wireless devices and BSs, and between BSs through wireless communication / connection 150a, 150b, and 150c. For example, signals may be sent and received on various physical channels through wireless communication / connection 150a, 150b, and 150c. To this end, at least a portion of various configuration information configuration processes, various signal processing processes (e.g., channel coding / decoding, modulation / demodulation, and resource mapping / demapping) and resource allocation processes for sending / receiving wireless signals may be performed based on various proposals of the present disclosure.

[0185] Fig.11 The diagram illustrates a wireless device suitable for use with the present disclosure.

[0186] refer to Fig.11 , the first wireless device 100 and the second wireless device 200 may transmit wireless signals via various RATs (eg, LTE and NR). {The first wireless device 100 and the second wireless device 200} may correspond to Fig.10 {wireless device 100x and BS 200} and / or {wireless device 100x and wireless device 100x}.

[0187] The first wireless device 100 may include one or more processors 102 and one or more memories 104, and may 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 operational 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 send a wireless signal including the first information / signals through the transceiver 106. The processor 102 may receive a wireless 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 a plurality of pieces of information related to the operation of the processor 102. For example, the memory 104 may store software codes including instructions for executing part or all of the processes controlled by the processor 102 or for executing the description, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document. 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 wireless signals through one or more antennas 108. Each of the transceivers 106 may include a transmitter and / or a receiver. The transceiver 106 may be used interchangeably with a radio frequency (RF) unit. In the present disclosure, a wireless device may be a communication modem / circuit / chip.

[0188] The second wireless device 200 may include one or more processors 202 and one or more memories 204, and may 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 send a wireless signal including the third information / signals through the transceiver 206. The processor 202 may receive a wireless signal including fourth information / signals through the transceiver 106, and then store the information obtained by processing the fourth information / signals in the memory 204. The memory 204 may be connected to the processor 202, and store various information related to the operation of the processor 202. For example, the memory 204 may store software code including instructions 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. 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 wireless signals through one or more antennas 208. Each of the transceivers 206 may include a transmitter and / or a receiver. The transceiver 206 may be used interchangeably with an RF unit. In the present disclosure, a wireless device may be a communication modem / circuit / chip.

[0189] Now, 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 physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), RRC, and service data adaptation protocol (SDAP)). The 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 flow charts disclosed in this document. The 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 flow charts disclosed in this document and provide the messages, control information, data, or information to one or more transceivers 106 and 206. The 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 flow charts disclosed in this document and provide the generated signal to the one or more transceivers 106 and 206. The one or more processors 102 and 202 may receive a signal (e.g., a baseband signal) from the 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 flow charts disclosed in this document.

[0190] The one or more processors 102 and 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. The one or more processors 102 and 202 may be implemented by hardware, firmware, software, or a combination thereof. For 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 the one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operational flowcharts 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 flowcharts disclosed in this document may be included in one or more processors 102 and 202, or may be stored in one or more memories 104 and 204 and executed by one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in this document may be implemented using firmware or software in the form of code, instructions, and / or instruction sets.

[0191] 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 to include read-only memory (ROM), random access memory (RAM), electrically erasable programmable read-only memory (EPROM), flash memory, hard disk drive, registers, cache memory, computer-readable storage media, and / or combinations 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 via various technologies such as wired or wireless connections.

[0192] One or more transceivers 106 and 206 can send user data, control information and / or wireless 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 can receive user data, control information and / or wireless 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 can be connected to one or more processors 102 and 202, and send and receive wireless signals. For example, one or more processors 102 and 202 can perform control so that one or more transceivers 106 and 206 can send user data, control information or wireless signals to one or more other devices. One or more processors 102 and 202 can perform control so that one or more transceivers 106 and 206 can receive user data, control information or wireless 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 wireless 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 wireless signals / channels, etc. from RF band signals to baseband signals so as to process received user data, control information and wireless signals / channels using one or more processors 102 and 202. One or more transceivers 106 and 206 may convert user data, control information, wireless signals / channels processed using one or more processors 102 and 202 from baseband signals to RF band signals. To this end, one or more transceivers 106 and 206 may include (analog) oscillators and / or filters.

[0193] The embodiments of the present disclosure described above are combinations of elements and features of the present disclosure. Unless otherwise stated, these elements or features may be considered as optional. Each element or feature may be practiced without being combined with other elements or features. In addition, the embodiments of the present disclosure may be constructed by combining a part of elements and / or features. The order of operations described in the embodiments of the present disclosure may be rearranged. Some constructions of any one embodiment may be included in another embodiment and may be replaced by the corresponding construction of another embodiment. It is obvious to those skilled in the art that claims that are not explicitly cited to each other in the attached claims may be presented as embodiments of the present disclosure in combination, or may be included as new claims by subsequent amendments after the application has been submitted.

[0194] The embodiments of the present disclosure have been described above in a manner focusing on the signal transmission and reception relationship between the UE and the BS. The signal transmission and reception relationship is extended to perform signal transmission and reception between the UE and the relay or between the BS and the relay in the same or similar manner. Specific operations described as being performed by the BS may be performed by upper nodes of the BS. That is, it is obvious that in a network consisting of multiple network nodes including the BS, various operations performed for communicating with the UE may be performed by the BS or network nodes other than the BS. The term BS may be replaced by the terms fixed station, Node B, enhanced Node B (eNodeB or eNB), access point, etc. In addition, the term UE may be replaced by the terms terminal, mobile station (MS), mobile subscriber station (MSS), etc.

[0195] Those skilled in the art will appreciate that the present disclosure can be performed in other specific ways different from those set forth herein without departing from the spirit and essential characteristics of the present disclosure. Therefore, the above embodiments are to be interpreted in all respects as illustrative and not restrictive. The scope of the present disclosure shall 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 range of the appended claims are intended to be included therein.

[0196] Industrial Applicability

[0197] The present disclosure may be used in a UE, a BS, or other devices in a mobile communication system.

Claims

1. A method for performing measurements for positioning by a user equipment (UE) in a wireless communication system, the method comprising: performing a first type of measurement for positioning including carrier phase measurements (CPM); performing a second type of measurements for positioning different from the first type of measurements; and reporting both the first type of measurement and the second type of measurement, The number of time instances related to the second type of measurement is equal to or greater than the number of time instances related to the first type of measurement.

2. The method according to claim 1, wherein: a single result obtained from the second type of measurements is associated with a plurality of results obtained from the first type of measurements, and The multiple results obtained from the first type of measurement have multiple timestamp values ​​that are different from each other.

3. The method according to claim 1, wherein: The first type of measurement is performed once for the single time instance, and the second type of measurement is performed multiple times for the multiple time instances.

4. The method according to claim 1, further comprising: A UE capability report is sent, the UE capability report comprising at least one of first information on whether the UE supports the first type of measurement and second information on a number of time instances for the second type of measurement supported by the UE.

5. The method according to claim 1, further comprising: Third information regarding a number of time instances related to the second type of measurements is received.

6. The method according to claim 5, wherein: The third information comprises a minimum number of time instances related to the second type of measurement.

7. The method according to claim 1, further comprising: The number of UE preferred time instances related to the second type of measurement is sent.

8. The method according to claim 1, wherein: The first type of measurements and the second type of measurements are reported by a single measurement report.

9. The method according to claim 8, wherein: The single measurement report comprises a number of time instances relating to the second type of measurements.

10. The method according to claim 8, wherein: The single measurement report includes timestamp information for the first type of measurement.

11. The method according to claim 10, wherein: The timestamp information for the first type of measurement indicates a time instance when the first type of measurement was performed.

12. The method according to claim 1, wherein: The second type of measurement includes at least one of a downlink reference signal time difference (DL-RSTD) measurement, an uplink relative time of arrival (UL-RTOA), or a receive-transmit time difference measurement.

13. A non-transitory medium storing instructions for causing a processor to execute the method of claim 1.

14. A device for wireless communication, the device comprising: a memory configured to store instructions; as well as a processor configured to perform operations by executing the instructions, The operations performed by the processor include: performing a first type of measurement for positioning including carrier phase measurements (CPM); performing a second type of measurements for positioning different from the first type of measurements; and reporting both the first type of measurement and the second type of measurement, The number of time instances related to the second type of measurement is equal to or greater than the number of time instances related to the first type of measurement.

15. The apparatus according to claim 14, further comprising: Transceiver, The device is a user equipment (UE) operating in a wireless communication system.

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