Method performed by user equipment in wireless communication network and user equipment

Abstract

The present disclosure relates to a pre-5th-Generation (5G) or 5G communication system to be provided for supporting higher data rates beyond a 4th-Generation (4G) communication system such as Long Term Evolution (LTE). A method of determining a user equipment (UE) location is disclosed wherein the UE communicates with at least two base stations (gNBs) of a telecommunications network, comprising the steps of: determining at least one of: a) an angle of arrival, AoA, of a signal from the UE at each of the at least two gNBs; b) the angle of departure AoD of the signal from each of the at least two gNBs; c) AoA at the UE of a signal from each of the at least two gNBs; d) an AoD of a signal from the UE at each of the at least two gNBs; and determining a location of the UE based thereon.

Description

[0001] This application is a divisional application of the invention patent application with the application date of September 30, 2019, application number 201980064184.9, and invention name “Improvements in angle-based positioning and measurement in telecommunication systems”. Technical Field

[0002] The invention relates to an angle-based positioning and measurement system in a telecommunication system. Background Art

[0003] To meet the increased demand for wireless data services since the deployment of 4G communication systems, efforts have been made to develop improved 5G or pre-5G communication systems. Therefore, 5G or pre-5G communication systems are also referred to as "beyond 4G networks" or "post-Long Term Evolution (LTE) systems."

[0004] 5G communication systems are considered to be implemented on higher frequency (millimeter wave) bands, for example, the 60 GHz band, in order to achieve higher data rates. To reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and massive antenna technology are discussed in 5G communication systems.

[0005] In addition, in 5G communication systems, system network improvements are being developed based on advanced small cells, cloud radio access networks (RANs), ultra-dense networks, device-to-device (D2D) communication, wireless backhaul, mobile networks, cooperative communications, coordinated multi-point (CoMP), receiving-end interference cancellation, etc.

[0006] In 5G systems, hybrid frequency shift keying (FSK) and quadrature amplitude modulation (FQAM) and sliding window superposition coding (SWSC) have been developed as advanced coded modulation (ACM), and filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse coded multiple access (SCMA) as advanced access technologies.

[0007] The demand for mobile services is increasing rapidly and one of the fastest growing segments is location-based services (LBS), driven by two main needs: emergency services and commercial applications. In response to these needs, second-generation networks and third-generation networks (WCDMA, GSM, CDMA) have added support for several positioning technologies, which vary in accuracy and first fix time (TTFF) performance. 3GPP Release 9 for LTE defines support for positioning technologies: Extended Cell ID (ECID), Assisted Global Navigation Satellite System (A-GNSS), Observed Time Difference of Arrival (OTDOA) and a new positioning protocol, LTE Positioning Protocol (LPP). A new reference signal has been defined in LTE, namely the Positioning Reference Signal (PRS). Further, in Release 11, the Uplink Observed Time Difference of Arrival (UOTDA) has been adopted using SRS measurements. 3GPP Release 15 defines support for some positioning technologies independent of Radio Access Technology (RAT), such as Real Time Kinematic (RTK) GNSS, to improve the accuracy of LTE positioning. Summary of the invention

[0008] Solution

[0009] Embodiments of the present disclosure are intended to solve problems of the prior art, whether mentioned herein or not.

[0010] From the disclosure, there is provided an apparatus and method as described herein. Other features of the invention will be apparent from the following description.

[0011] According to the disclosure, a positioning method based on angle, and / or signal strength, and / or arrival time, and / or arrival time difference is provided. The embodiments utilize corresponding UE capability reporting and measurement procedures and metrics.

[0012] According to a first aspect of the disclosure, a method for determining a position of a user equipment UE is provided, wherein the UE communicates with at least two base stations (gNBs) of a telecommunication network, comprising the steps of: determining at least one of the following: a) an angle of arrival AoA of a signal from the UE at each of the at least two gNBs; b) an angle of departure AoD of a signal from each of the at least two gNBs; c) an AoA of a signal from each of the at least two gNBs at the UE; d) an AoD of a signal from the UE at each of the at least two gNBs; and determining the position of the UE based thereon.

[0013] In an embodiment, for option a) or option d), the signal is one of: a reference signal such as SRS, DMRS, PTRS and PRACH; or a data transmission.

[0014] In an embodiment, for option b) or option c), the signal is one of CSI-RS / TRS, DMRS, PTRS and SS.

[0015] In an embodiment, for option a), a first of the at least two gNBs transmits its AoA signal to a second of the at least two gNBs, such that the second of the at least two gNBs determines the location of the UE based on the AoA from the first of the at least two gNBs and its own AoA.

[0016] In an embodiment, for option b), the AoD of each of the at least two gNBs is determined based on the precoding matrix and each gNB sends its AoD together with its own location information to the UE, so that the UE determines its own position.

[0017] In an embodiment, for option c), if the at least two gNBs are equal to two gNBs, the UE additionally needs its own position.

[0018] In an embodiment, the UE obtains its own orientation through a sensor such as a gyroscope installed in the UE.

[0019] In an embodiment, for option c), if the at least two gNBs are equal to three gNBs, the UE does not need its own position to determine its position.

[0020] In an embodiment, for option d), AoD information associated with each of the at least two gNBs is sent from the UE to at least one of the at least two gNBs, enabling that gNB to determine the location of the UE.

[0021] In an embodiment, in the case where there are reflectors in the path between at least one gNB and the UE, one or more further parameters are utilized to determine the UE position.

[0022] In an embodiment, one or more further parameters relate to signal strength such that path loss can be determined in conjunction with signals transmitted between the UE and at least one gNB.

[0023] In an embodiment, the one or more further parameters relate to a timing advance or a round trip time RTT.

[0024] In an embodiment, more than one of options a) to d) is used to determine the UE location.

[0025] In an embodiment, certain parameters used to determine the UE's position are specific to the particular RAT in use, and certain other parameters are independent of the particular RAT in use.

[0026] In an embodiment, the UE signals a capability report to the network including information about the UE's capability to perform angle-based positioning.

[0027] According to a second aspect of the disclosure, there is provided a UE communicating with at least two gNBs, operable to determine its position based on one or more of an angle of departure AoD of a signal from each of the at least two gNBs or an angle of arrival AoA of a signal from each of the at least two gNBs at the UE.

[0028] According to a third aspect of the disclosure, there is provided a gNB communicating with a UE, operable to determine a location of the UE based on an angle of arrival AoA of a signal from the UE at the gNB or at least one other gNB or an angle of departure AoD of a signal from the UE at the gNB or at least one other gNB.

[0029] According to a fourth aspect of the disclosure, there is provided a method performed by a user equipment (UE) in a wireless communication network, the method comprising: receiving information about an angle of departure (AoD) positioning method, the information comprising direction information about each of a plurality of nodes and position information about each of the plurality of nodes; receiving downlink reference signals from the plurality of nodes; determining the position of the UE based on the information about the AoD positioning method and a reference signal received power (RSRP) measurement of the downlink reference signal; and sending information about the position of the UE and confidence information related to accuracy to a location server, wherein the direction information comprises information about an angle associated with a reference direction that is geographically north.

[0030] According to a fifth aspect of the disclosure, a user equipment (UE) in wireless communication is provided, comprising: at least one transceiver; and at least one processor, coupled to the at least one transceiver, and configured to: receive information about an angle of departure (AoD) positioning method, the information comprising direction information about each of a plurality of nodes and position information about each of the plurality of nodes, receive downlink reference signals of a plurality of nodes from the plurality of nodes, determine the position of the UE based on the information about the AoD positioning method and a reference signal received power (RSRP) measurement of the downlink reference signal, and send information about the position of the UE and confidence information related to accuracy to a location server, wherein the direction information comprises information about an angle associated with a reference direction that is geographically north.

[0031] For network-based angle-based positioning, the disclosed embodiments utilize AoA-based and AoD-based positioning schemes used within the NR framework.

[0032] The disclosed embodiments utilize UE-based angle-based positioning, where the UE position is used for positioning.

[0033] The disclosed embodiments utilize hybrid positioning, combining angles and other measurements, where not only line of sight (LOS) but also non-LOS (NLOS) is supported.

[0034] In the disclosed embodiments, positioning may be based on UE capabilities, for example, the number of antenna elements on the UE side.

[0035] In the disclosed embodiment, measurement metrics are defined for NR angle-based positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] While certain preferred embodiments of the disclosure have been shown and described, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the scope of the invention.

[0037] For a better understanding of the invention, and to show how embodiments of the invention may be effected, reference will be made, by way of example only, to the accompanying schematic drawings, in which:

[0038] Figure 1 A wireless communication system according to an embodiment is illustrated;

[0039] Figure 2 A base station in a wireless communication system according to an embodiment is illustrated;

[0040] Figure 3 A terminal in a wireless communication system according to an embodiment is illustrated;

[0041] Figure 4 A communication unit in a wireless communication system according to an embodiment is illustrated;

[0042] Figure 5 shows AoA / AoD based positioning according to an embodiment of the invention;

[0043] Figure 6 The figure shows the positioning based on AoA / AoD at the UE side according to an embodiment of the invention;

[0044] Figure 7 The effect of UE orientation on positioning is shown;

[0045] Figure 8 A flow chart according to an embodiment of the disclosure is shown;

[0046] Fig. 9 shows AoA / AoD based positioning according to an embodiment of the invention; and

[0047] Fig.10 An arrangement for positioning using two reflectors according to a disclosed embodiment is shown. DETAILED DESCRIPTION

[0048] The terms used in the present disclosure are used to describe a particular embodiment and are not intended to limit the present disclosure. Unless clearly different from the context or unless otherwise clearly indicated, a singular expression may include a plural expression. Further, unless otherwise defined, all terms used herein, including technical and scientific terms, may have the same meaning as the meaning generally understood by those skilled in the art to which the present disclosure belongs. Among the terms used in the present disclosure, the terms defined in a general dictionary may be interpreted as having the same or similar meaning as the context of the relevant technology, and, unless clearly defined in the present disclosure, it should not be ideally or excessively interpreted as a formal meaning. In some cases, even when terms are defined in the present disclosure, these terms should not be interpreted as excluding embodiments.

[0049] In various embodiments to be described below, hardware methods may be described as examples. However, it will be understood that various embodiments may include techniques using both hardware and software, and various embodiments do not exclude software-based methods.

[0050] Various embodiments provide an apparatus and method for selecting a beam in a wireless communication system. More specifically, the present disclosure describes a technique for selecting a common beam for multiple carriers in a wireless communication system.

[0051] The terms indicating a signal, the terms indicating a propagation characteristic (e.g., directivity) of a signal, the terms indicating control information, the terms indicating a network entity, and the terms indicating a component of a device used in the following description are for explanation. Therefore, the present disclosure is not limited to the terms to be described, and other terms having technically the same or similar meanings may be used.

[0052] In this disclosure, in order to determine whether a specific condition is satisfied or achieved, expressions such as "greater than" or "less than" are used by way of example, and expressions such as "greater than or equal to" or "less than or equal to" are also applicable and are not excluded. For example, a condition defined as "greater than or equal to" can be replaced with "greater than" (or vice versa), a condition defined as "less than or equal to" can be replaced with "less than" (or vice versa), etc.

[0053] The present disclosure provides various embodiments using terminology used in some communication standards by way of example. The various embodiments can be easily used in or can be applied to other communication systems.

[0054] Figure 1 A wireless communication system according to an embodiment is illustrated. Figure 1 Base station 110, terminal 120, and terminal 130 are depicted as some nodes using radio channels in a wireless communication system. Figure 1A single base station is depicted, but another base station that is the same as or similar to base station 110 may be further included.

[0055] The base station 110 is a network infrastructure that provides wireless access to the terminal 120 and the terminal 130. The base station 110 has a coverage area defined as a geographical area based on a signal transmission distance. The base station 110 may be referred to as an access point (AP), an eNodeB (eNB), a fifth generation node (5G node), a next generation nodeB (gNB), a wireless point, a transmission / reception point (TRP), or other terms having technically equivalent meanings.

[0056] Each of the terminal 120 and the terminal 130 is used by a user and communicates with the base station 110 through a radio (or wireless) channel. In some cases, at least one of the terminal 120 and the terminal 130 may work without user participation. That is, at least one of the terminal 120 and the terminal 130 may perform machine type communication (MTC) and may not be carried by the user. Each of the terminal 120 and the terminal 130 may be referred to as a user equipment (UE), a mobile station, a subscriber station, a remote terminal, a wireless terminal, a user device, or other terms having technically equivalent meanings.

[0057] The base station 110, the terminal 120, and the terminal 130 can send and receive radio signals (e.g., wireless signals) in a millimeter wave (mmWave) band (e.g., 28 GHz, 30 GHz, 38 GHz, 60 GHz). In order to improve the channel gain, the base station 110, the terminal 120, and the terminal 130 can perform (or execute) beamforming. In this article, beamforming may include transmit beamforming / transmission beamforming and receive beamforming / receive beamforming. That is, the base station 110, the terminal 120, and the terminal 130 can apply directionality to the transmitted signal or the received signal. To this end, the base station 110 and the terminal 120 and the terminal 130 can select the service beams 112, 113, 121, and 131 through a beam search or beam management process. After the service beams 112 , 113 , 121 , and 131 are selected, communication may be performed using quasi-co-located (QCL) resources and resources for transmitting the service beams 112 , 113 , 121 , and 131 .

[0058] If large-scale properties of a channel carrying symbols on the first antenna port can be inferred from a channel carrying symbols on the second antenna port, the first antenna port and the second antenna port can be referred to as QCLs. For example, the large-scale properties may include at least one of delay spread, Doppler spread, Doppler shift, average gain, average delay, and spatial reception parameters.

[0059] Figure 2 A base station 110 in a wireless communication system according to an embodiment is illustrated. Figure 2 The configuration of the base station 110 is depicted. In the following description, it will be understood that terms such as "module", "unit", "part" or "-or-er" indicate a unit for processing at least one function or operation and can be implemented using hardware, software, or a combination of hardware and software.

[0060] refer to Figure 2 The base station 110 includes a wireless communication unit 210 (e.g., a wireless communicator or a wireless communication interface), a backhaul communication unit 220 (e.g., a backhaul communicator or a backhaul communication interface), a storage unit 230 (e.g., a memory), and a control unit 240 (e.g., at least one processing device).

[0061] The wireless communication unit 210 can send and receive signals through a radio (or wireless) channel. For example, the wireless communication unit 210 performs a conversion function between a baseband signal and a bit string (or bit stream) according to the physical layer standard of the system. As a further example, when data is sent, the wireless communication unit 210 generates complex symbols by encoding and modulating the transmission bit string (or transmission bit stream). Similarly, when data is received, the wireless communication unit 210 recovers the reception bit string (or reception bit stream) by demodulating and decoding the baseband signal.

[0062] In addition, the wireless communication unit 210 up-converts the baseband signal to a radio frequency (RF) band signal, transmits the RF band signal via the antenna, and down-converts the RF band signal received via the antenna to a baseband signal. To this end, the wireless communication unit 210 may include at least one of a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a digital-to-analog converter (DAC), an analog-to-digital converter (ADC), etc. In addition, the wireless communication unit 210 may include or utilize multiple transmit / transmission and receive / reception paths. Further, the wireless communication unit 210 may include at least one antenna array including multiple antenna elements.

[0063] In terms of hardware, the wireless communication unit 210 may include a digital unit and an analog unit, and the analog unit may include multiple subunits according to operating power and operating frequency. The digital unit may include at least one processor (eg, a digital signal processor (DSP)).

[0064] As described above, the wireless communication unit 210 transmits and receives signals. Therefore, all or part of the wireless communication unit 210 may be referred to as a transmitter, a receiver, or a transceiver. Hereinafter, transmission and reception through a radio (or wireless) channel may include the above-mentioned processing of the wireless communication unit 210.

[0065] The backhaul communication unit 220 provides an interface for communicating with other nodes in the network. That is, the backhaul communication unit 220 converts a bit string sent from the base station 110 to another node, for example, to another access node, another base station, an upper node, or a core network, into a physical signal, and converts a physical signal received from another node into a bit string.

[0066] The storage unit 230 stores data such as basic programs, applications, configuration information, settings, etc. for operating the base station. The storage unit 230 may include a volatile memory, a nonvolatile memory, or a combination of a volatile memory and a nonvolatile memory. The storage unit 230 provides the stored data in response to a request from the control unit 240.

[0067] The control unit 240 controls the general operation of the base station. For example, the control unit 240 sends and receives signals through the wireless communication unit 210 or the backhaul communication unit 220. Moreover, the control unit 240 records data to the storage unit 230 and reads data from the storage unit 230. The control unit 240 can perform the functions of the protocol stack required by a specific communication standard or included in a specific communication standard. According to another embodiment, the protocol stack can be included in the wireless communication unit 210 and / or implemented via the wireless communication unit 210. To this end, the control unit 240 may include at least one processor.

[0068] According to an embodiment, the control unit 240 may determine at least one beam for communicating with a terminal (e.g., terminal 120). For example, the control unit 240 may determine a transmit (transmit / transmission) beam of the base station 110 based on feedback from the terminal. Further, the control unit 240 may determine at least one of a receive (receive / reception) beam of the base station 110 and a transmit beam of the terminal using a signal sent from the terminal 110. Additionally, the control unit 240 may send information indicating the determined transmit beam of the terminal to the terminal. For example, according to one or more embodiments, the control unit 240 may control the base station 110 to implement the operations described below.

[0069] Figure 3 The terminal 120 in the wireless communication system according to the embodiment is illustrated. In the following description, it will be understood that terms such as "module", "unit", "part" or "device" indicate a unit for processing at least one function or operation and can be implemented using hardware, software, or a combination of hardware and software.

[0070] refer to Figure 3 , the terminal 120 includes a communication unit 310 (e.g., a communicator or a communication interface), a storage unit 320 (e.g., a memory), and a control unit 330 (e.g., at least one processor). As an example, the terminal 120 can be a cellular phone or other device that communicates through a cellular network (e.g., a 5G or pre-5G network).

[0071] The communication unit 310 can send and receive signals through a radio channel. For example, the wireless communication unit 310 performs a conversion function between a baseband signal and a bit string according to the physical layer standard of the system. As a further example, when data is sent, the communication unit 310 generates a complex symbol by encoding and modulating the transmission bit string. Similarly, when data is received, the wireless communication unit 210 recovers the received bit string by demodulating and decoding the baseband signal. In addition, the communication unit 310 up-converts the baseband signal to an RF band signal, transmits the RF band signal via an antenna, and down-converts the RF band signal received via the antenna to a baseband signal. For example, the wireless communication unit 210 may include at least one of a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, etc.

[0072] Moreover, the communication unit 310 may include or utilize multiple transmit and receive paths. Further, the communication unit 310 may include at least one antenna array including multiple antenna elements. In terms of hardware, the communication unit 310 may include digital circuits and analog circuits (e.g., RF integrated circuits (RFIC)). In this article, the digital circuits and analog circuits may be implemented as a single package. Moreover, the communication unit 310 may include multiple RF chains. Further, the communication unit 310 may perform beamforming.

[0073] As described above, the communication unit 310 transmits and receives signals. Therefore, all or part of the communication unit 310 may be referred to as a transmitter, a receiver, or a transceiver. Hereinafter, transmission and reception through a radio channel may include the above-mentioned processing of the communication unit 310.

[0074] The storage unit 320 stores data such as basic programs, applications, configuration information, settings, etc. for operating the base station. The storage unit 320 may include a volatile memory, a nonvolatile memory, or a combination of a volatile memory and a nonvolatile memory. The storage unit 320 provides the stored data in response to a request from the control unit 330.

[0075] The control unit 330 controls the general operation of the terminal. For example, the control unit 330 sends and receives signals through the communication unit 310. Moreover, the control unit 330 records data to the storage unit 320 and reads data from the storage unit 320. The control unit 330 can perform the functions of the protocol stack required by a specific communication standard or included in a specific communication standard. To this end, the control unit 330 may include at least one processor or microprocessor, or may be a part of a processor. The communication unit 310 and a part of the control unit 330 may be referred to as a communication processor (CP).

[0076] According to an embodiment, the control unit 330 may determine at least one beam for communicating with a base station (e.g., the base station 110). The control unit 330 may determine at least one of a receiving beam of the terminal 120 and a transmitting beam of the base station using a signal transmitted from the base station. Further, the control unit 330 may send information indicating the determined transmitting beam of the base station to the base station. For example, the control unit 330 may determine the transmitting beam of the base station based on a request from the base station. Further, for example, according to one or more embodiments, the control unit 330 may control the terminal to implement the operations described below.

[0077] Figure 4 The communication unit 210 or the communication unit 310 in the wireless communication system according to the embodiment is illustrated. Figure 4 Depicted Figure 2 The wireless communication unit 210 or Figure 3More specifically, Figure 4 Depicted as Figure 2 The wireless communication unit 210 or Figure 3 A component of a portion of the communication unit 310 for performing beamforming.

[0078] refer to Figure 4 The wireless communication unit 210 or the communication unit 310 includes an encoder and modulator 402 , a digital beamformer 404 , a plurality of transmit / transmission paths 406 - 1 to 406 -N, and an analog beamformer 408 .

[0079] The encoder and modulator 402 performs channel coding. In order to perform channel coding, at least one of a low density parity check (LDPC) code, a convolutional code, and a polarization code may be used. The encoder and modulator 402 generates modulation symbols through constellation mapping.

[0080] The digital beamformer 404 performs beamforming on a digital signal (e.g., a modulation symbol). To this end, the digital beamformer 404 may multiply or apply a beamforming weight to the modulation symbol. In this document, the beamforming weight is used to change the level and phase of the signal and may be referred to as a precoding matrix or precoder. The digital beamformer 404 outputs the digital beamformed modulation symbol to a plurality of transmission paths 406-1 to 406-N. In this case, according to a multiple-input multiple-output (MIMO) transmission scheme, the modulation symbols may be multiplexed or the same modulation symbol may be fed to a plurality of transmission paths 406-1 to 406-N.

[0081] Transmitting paths 406-1 to 406-N convert digital beamforming digital signals into analog signals. To this end, each of the transmitting paths 406-1 to 406-N may include an inverse fast Fourier transform (IFFT) operator, a cyclic prefix (CP) adder or inserter, a DAC, and an up-converter. The CP adder is used for orthogonal frequency division multiplexing (OFDM), and if another physical layer scheme (e.g., filter bank multi-carrier (FBMC)) is applied, it can be excluded. That is, transmitting paths 406-1 to 406-N provide independent signal processing for multiple streams generated by digital beamforming. It is noteworthy that, depending on the implementation, some components of the transmitting paths 406-1 to 406-N may be shared.

[0082] The analog beamformer 408 performs beamforming on the analog signal. To this end, the analog beamformer 408 can multiply the beamforming weights with the modulation symbols or apply them to the modulation symbols. In this article, the beamforming weights are used to change the level and phase of the signal. More specifically, the analog beamformer can be configured differently according to the connection structure between the transmission paths 406-1 to 406-N and the antennas. For example, each of the transmission paths 406-1 to 406-N can be connected to an antenna, or the transmission paths 406-1 to 406-N can be connected to an antenna array. Further, the transmission paths 406-1 to 406-N can be adaptively connected to an antenna array, or can be connected to two or more antenna arrays.

[0083] In addition to the positioning techniques of the prior art, new positioning techniques that exploit NR characteristics such as wider bandwidth and a large number of antenna elements can also be utilized to achieve high positioning accuracy. The measurement accuracy of the angle of arrival (AoA) is proportional to the number of antenna elements on the receiver side. In this sense, NR base stations (gNBs) with more antenna elements are expected to provide higher accuracy. Further, more complex UEs with improved hardware can be supported in the fifth generation (5G), which makes it possible to perform AoA measurements on the UE side that are generally not present in the prior art, mainly due to limited computing power and available facilities. In essence, in an embodiment of the present disclosure, depending on UE capabilities, signal reciprocity, etc., AoA measurements can occur on both sides of the communication link (e.g., UE or gNB), and the UE position can be potentially calculated on both sides. In addition, such measurements can be combined with other radio access technology (RAT)-dependent measurements such as arrival time difference, or even with RAT-independent measurement techniques such as gyroscopes to further improve positioning accuracy or reduce positioning latency.

[0084] Here, it is assumed that the base station (BS) location and the orientation of its antenna array are known at both the BS and the UE via signaling.

[0085] Case 1

[0086] like Figure 5As shown, AoA can be measured at more than one gNB to locate the UE. It is assumed that the horizontal antenna array orientations at two gNBs - θ1 and θ2 (respective angles of arrival) - can be measured at each gNB based on signals sent from the UE. Such signals can be reference signals or data transmissions such as SRS, DMRS, PTRS and PRACH. The two gNBs need to exchange their AoA information so that the position of the UE can be calculated. Alternatively, one or more gNBs can inform the other gNB(s) that one gNB is responsible for calculating the position of the UE. A method for designating a gNB responsible for the calculation can be provided.

[0087] In such a case, at least two gNBs are required, while more gNBs can improve positioning accuracy. It should also be noted that it is not necessary to measure AoA at the gNB, but a logical or physical node can be defined and co-located with the gNB for AoA measurements, similar to the Location Measurement Unit (LMU) in LTE. This approach is network-based.

[0088] Condition 2

[0089] Another method is a UE-based positioning method based on the Angle of Departure (AoD) from the gNB. Since the beam pattern and direction are determined by the precoding matrix known to the gNB, the AoD is known to the gNB and, therefore, the AoD can be derived from such information. The gNB can send the AoD, its own position and antenna array orientation information along with its reference signal or data transmission to the UE via an upper layer protocol, such as LPP. Once the UE receives such information, it can calculate its own position and send its position back to the network. The reference signal used by the gNB for this purpose can be CSI-RS / TRS, DMRS, PTRS or SS. It should be noted that the UE needs to identify from which gNB the reference signal was received.

[0090] Case 3

[0091] AoA can also be measured at the UE using multiple antenna elements implemented for 5G user terminals. Figure 6 As shown in Figure 1, since the UE can move and rotate, the UE may not know the orientation of its own antenna array. is unknown to the UE and assuming the UE position is (x, y), there are three unknown quantities in total x and y. For each gNB transmission, an equation can be obtained as follows. To solve all three unknowns, three equations are required, so this method requires at least three gNBs. The reference signal used for such AoA measurement can be CSI-RS / TRS, DMRS, SS or PTRS.

[0092]

[0093] In order to determine the AoD from the gNB, the UE needs a reference direction, e.g., North. Essentially, if the UE orientation is unknown, the UE does not know which direction the reference direction is and thus the AoD information is useless.

[0094] like Figure 7 As shown, it should be noted that in the UE 700 position, the coordinate system is rotated Therefore, for the first gNB 10, we can formulate the equation

[0095]

[0096] Then for the second gNB 20, we can form another equation

[0097]

[0098] If we have a third gNB, we can also form a third equation. Using the three equations, we can solve for the three unknown variables x, y and here, is not measured but considered as an unknown variable.

[0099] Therefore, there is no need to measure

[0100] In another example, Can be measured by a gyroscope, which is commonly installed in many mobile devices and can be used to measure This is Figure 7 It is illustrated in the right part of , which shows two gNBs 30, 40 and UE 710.

[0101] In this case, three gNBs are not required and measuring AoD from two gNBs 30, 40 is sufficient.

[0102] As described in detail later, the UE orientation can be measured by a gyroscope in the UE.

[0103] Figure 8A flow chart associated with the technique described above is shown. The flow starts at S10. At S20, it is determined whether the UE includes an installed gyroscope that can be used to determine the UE's position. If such a gyroscope is installed, then at step S30, the UE's position is measured using the gyroscope. Then at step S40, AoD is measured from at least two gNBs, and at step S60, the UE is positioned based on these measurements.

[0104] At step S20, if a gyroscope is not installed, then at step S50, AoD is measured from at least three gNBs, and at step S60, the UE is positioned based on these measurements.

[0105] Case 4

[0106] Another method is a network-based positioning method based on the AoD from the UE. The UE can send the AoD along with its reference signal or data transmission to the gNB via an upper layer protocol, such as LPP, and once the gNBs get such information, they can calculate the UE position. Alternatively, one or more gNBs can inform other gNB(s) that one gNB is responsible for calculating the UE's position. A method for designating one gNB responsible for the calculation can be provided.

[0107] The reference signal used for such purpose can be SRS, DMRS, PTRS or PRACH. Multiple transmissions are required and they can occur simultaneously via multiple beams or in TDM mode. In the latter case, the gNBs are required to exchange AoD information so that the UE's position can be calculated.

[0108] Angle-based positioning requires beamforming. However, even if positioning occurs when the RRC is connected so that the UE is covered, the UE is still moving so that the UE may move out of coverage and lose the RRC connection. It is more preferable to have a wider beam to ensure that the UE is in coverage in an emergency. Beam width adaptation for positioning configured by upper layer signaling should be supported, and the adaptation criteria can be UE speed, urgency level of the positioning request, priority of the positioning request, etc.

[0109] It is usually assumed that only narrow beams are used for angle-based positioning. Therefore, positioning measurements are based on assumed beam centers. There may be some ambiguity, but positioning is accurate enough if multiple gNBs are used.

[0110] In the above mentioned angle based positioning embodiment, a line of sight (LOS) link is assumed. However, there is not always a LOS link between the gNB and the UE. In this case, other measurements are needed for positioning.

[0111] Case 1: Angle + Signal Strength (RSRP / RSRQ / SINR)

[0112] like Fig. 9 As shown, when considering a non-LOS (NLOS) link between gNB1 900 and UE 920, in addition to the UE 920 position, the reflector 910 (e.g., a building or other structure) position is also unknown. There are a total of 5 unknown values, including the UE position (x, y), the reflector position (x1, y1), and the UE orientation. If AoA or AoD is measured only on one side (i.e., at the gNB 900 or at the UE 920), it is obviously impossible to form sufficient equations to solve to locate the UE 220.

[0113] Here, signal strength and such information along with path loss information in terms of RSRP, RSRQ or SINR can be used to estimate the path length of the signal traveling from the gNB to the UE or vice versa. In the absence of channel reciprocity, it is necessary to know the AoD on the network side, the AoA on the UE side, and the signal strength on the UE side to form three equations for each NLOS path. With an additional NLOS path, there are two more unknown variables for the new reflector, but more than three equations can be formed. Assuming an NLOS path L, L needs to satisfy the following conditions:

[0114] 5+2*(L-1)<=3*L

[0115] And the minimum L is 3, which means at least 3 NLOS paths are needed to locate the UE.

[0116] When channel reciprocity is maintained, instead of measuring AoA on one side and AoD on the other side, AoA / AoD can be measured on both sides and then such information is shared to the other side via upper layer signaling, e.g., LPP, to locate the UE. In order to have at least 3 NLOS paths, the following two options can be considered:

[0117] Simultaneous multi-beam or wide beam with simultaneous multiple NLOS paths;

[0118] TDM beams.

[0119] For the first option, the reference signals that can be used for DL ​​can be CSI-RS / TRS, DMRS, SS, PTRS and the reference signals that can be used for UL can be SRS, DMRS, PTRS and PRACH. If multi-beams are used, the beam index should be indicated so that there is a one-to-one mapping between the beams and the respective AoA / AoD pair values ​​in SDM mode for the first option or in TDM mode for the second option. If wide beams with simultaneous multiple NLOS paths are used, the AoA / AoD values ​​can be sorted and paired with each other.

[0120] For NLOS, it is necessary to know the position of the reflectors. Each reflector position brings two unknown variables. At the same time, as mentioned, equations can be formed based on the measurement results. If the number of equations is greater than the number of unknown variables, the unknown variables can be solved and this situation provides sufficient information.

[0121] The position of the obstacle should be known because it is needed to calculate the AoA and the length of the path that the signal propagates when there is an obstacle. The AoA and path length are changed from the LOS situation. This information can then be used to locate the UE.

[0122] It should be noted that the signal strength may vary based on the surface material, but it is possible to assume reflectivity and then take that into account when measuring the signal strength. This is not an ideal solution, but provides a perfect working technique in practice.

[0123] It should be noted that there may be multiple obstacles. However, the most common case is that the signal is reflected only once in any given path and this is the case considered here. If the signal is reflected by more than one obstacle in a given path, the UE may not be located by using embodiments of the present invention.

[0124] In the following cases, for simplicity, assume that is 0. If If it is non-zero, the previously mentioned methods can be used.

[0125] Fig.10 Shown is a case with two separated reflectors, such a signal from gNB1 1000 has been reflected from reflector 1 1010 separated from reflector 2 1015 and reaches UE 1020. The following definitions are used for the following:

[0126] gNB1 position (x0,y0) = (0,0)

[0127] Reflector1's position (x1, y1)

[0128] Reflector2 position (x2, y2)

[0129] UE location (x,y).

[0130] From these, the following equation can be formed:

[0131]

[0132] The length of the signal travel path = (x1^2+y1^2)^0.5+((x1-x)^2+(y1-y)^2)^0.5. Using the signal strength and path loss model, another equation can be defined.

[0133] Signal strength = path loss (the length of the path the signal travels)

[0134] Therefore, there are three equations in total. Using reflector 2, three equations can be formed in a similar manner, but with two unknown variables x2 and y2. Therefore, there are 6 unknown variables and 6 equations in total. Therefore, the unknown variables can be solved.

[0135] Case 2: Angle + Timing Advance / Round Trip Time (RTT)

[0136] The principle here is the same as in case 1 above, but the signal strength is replaced by the timing advance, which can be used to derive the RTT and distance between the gNB and the UE. With this information, the same approach as in case 1 can be used.

[0137] Case 3: Angle + arrival time difference

[0138] In this case, the arrival time difference can be combined with the angle-based positioning. For each additional NLOS link, the arrival time difference provides another equation in addition to AoA / AoD. Assuming an NLOS path L, L needs to satisfy the following condition:

[0139] 5+2*(L-1)<=2+3*(L-1)

[0140] Here L should be at least 4, which means that 4 paths are needed for positioning. For the measurement of arrival time difference, CSI-RS / TRS, SS and PRS can be considered in DL, while PRACH and DMRS can be considered for UL.

[0141] It should be noted that the required L-path can be from the same gNB or different gNBs. AoA / AoD information can be shared via upper layer signaling, such as LPP / LPPa. It should also be noted that LOS is a special case of NLOS, so there may be a LOS path in the L-path.

[0142] RAT-dependent positioning can also be combined with RAT-independent positioning methods to improve accuracy or reduce latency and complexity. In the previous case, the UE position is unknown. However, with the assistance of RAT-independent positioning techniques such as gyroscopes as described above, the UE position can be known. In this case, the number of unknown variables is reduced. For case 1, angle + signal strength (RSRP / RSRQ / SINR), the number of NLOS links required is reduced to 2, and for case 2, angle + arrival time difference, the number of NLOS links required is reduced to 3. The UE position information can be shared via upper layer signaling, such as LPP / LPPa.

[0143] The accuracy of the angle measurement and the time difference of arrival depends on the number of antenna elements and the bandwidth, respectively. The UE may have different capabilities to support a specific number of active antenna elements for a specific bandwidth. In this regard, the UE needs to report its capabilities to the gNB so that the gNB knows whether angle-based positioning can be performed on the UE side. If the UE reports back its maximum supported bandwidth, the gNB is also able to know the accuracy of the time difference measurement at the UE. Basically, the UE should report back its antenna and supported bandwidth related information to the gNB and the location server, and thus the location server is able to determine which positioning solution is the most suitable one.

[0144] When positioning reference signal is configured, it can be TDM and / or FDM from multiple transmission points (TPs). However, code division multiplexing (CDM) can also be supported to reduce signaling overhead. In this case, the time difference accuracy requirement is different from TDM and FDM and the UE should report whether it can support CDM for positioning reference signal.

[0145] Another issue is the confidence of the positioning that should be reported by the UE or gNB to the positioning server. The confidence reflects how accurate the positioning measurement is expected to be and it depends on multiple factors, such as the signal strength of the positioning signal (e.g., RSRP / RSRQ / SINR of the positioning reference signal) or the variation of the signal strength, the number of antenna elements (e.g., for angle-based measurements), and the number of nodes involved in the positioning measurement. These metrics can also be shared between the network and the UE with the positioning measurement results. The following options can be used to report such metrics.

[0146] • All metrics need to be reported by the entity doing the measurement. For network based methods, the UE makes the report, and for UE based methods, the network can report such metrics.

[0147] • A subset of these metrics is reported based on upper layer configuration and this subset can also be modified by upper layer configuration.

[0148] It should be noted that the metrics themselves can be reported at different timing granularities depending on the requirements. For example, signal strength reports require regular and relatively frequent reporting, but the number of nodes involved in positioning measurements can be much less frequent.

[0149] As mentioned earlier, the following measurements are performed to support positioning in NR.

[0150] AoA

[0151] ·AoD

[0152] Arrival time

[0153] Arrival time difference

[0154] Signal strength

[0155] Signal strength measurement has been defined in NR using CSI-RS or SS and it can be easily extended to other reference signals for positioning. AoD can be obtained by analyzing the precoding matrix or measuring the AoD while maintaining channel reciprocity.

[0156] For AoA, the following measurements are defined.

[0157]

[0158] For the time difference of arrival (reference signal time difference (RSTD)), the following measurements need to be defined.

[0159]

[0160] For arrival time, the following measurements need to be defined.

[0161]

[0162]

[0163] Some techniques require joint measurements of angle and RSRP, angle and timing advance, and angle and time difference of arrival. Some joint measurements can be defined by combining the above definitions.

[0164] At least some of the example embodiments described herein can be constructed partially or entirely using dedicated hardware.Terms such as "component", "module" or "unit" used herein may include but are not limited to hardware devices, such as circuits, field programmable gate arrays (FPGA) or application specific integrated circuits (ASIC) in the form of separate or integrated components, which perform certain tasks or provide related functions.In some embodiments, the element described may be configured to reside on a tangible, persistent, addressable storage medium and may be configured to be executed on one or more processors.In some embodiments, these functional elements may include, for example, components, processes, functions, attributes, programs, subroutines, program code segments, drivers, firmware, microcodes, circuits, data, databases, data structures, tables, arrays and variables such as software components, object-oriented software components, class components and task components.Although example embodiments have been described with reference to components, modules and units discussed herein, such functional elements may be combined into fewer elements or separated into additional elements.Various combinations of optional features have been described herein, and it will be understood that the described features may be combined in any suitable combination. In particular, the features of any one exemplary embodiment may be appropriately combined with the features of any other embodiment, unless such combinations are mutually exclusive. Throughout the specification, the term "comprising" means including specified components but does not exclude the presence of other components.

[0165] Attention is directed to all papers and documents which are filed concurrently with or before this specification in connection with this application and which are open to the public with the present specification, and the contents of all these papers and documents are incorporated herein by reference.

[0166] All features disclosed in this specification (including any accompanying claims, abstract and drawings) and / or all steps of any method or process so disclosed may be combined in any combination, except combinations where at least some of these features and / or steps are mutually exclusive.

[0167] Unless otherwise expressly stated, each feature disclosed in this specification (including any attached claims, abstracts and drawings) may be replaced by alternative features having the same, equivalent or similar purpose. Therefore, unless otherwise expressly stated, each feature disclosed is only an example of a series of equivalent or similar features.

[0168] The invention is not limited to the details of the foregoing embodiments. The invention extends to any novel one or any novel combination of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one or any novel combination of the steps of any method or process disclosed in this specification.

Claims

1. A method performed by a user equipment (UE) in a wireless communication network, the method comprising: receiving information about an angle of departure (AoD) positioning method, the information including direction information about each of a plurality of nodes and position information about each of the plurality of nodes; receiving downlink reference signals from a plurality of nodes; determining a location of the UE based on the information about the AoD positioning method and a reference signal received power (RSRP) measurement of a downlink reference signal; as well as Sending the UE's location information and confidence information related to the accuracy to the location server, The direction information includes information on an angle associated with a reference direction that is geographically north.

2. The method according to claim 1, wherein: The location of the UE is further determined based on at least one sensor including a gyroscope.

3. The method according to claim 1, wherein: Multiple nodes are associated with the next generation nodeB (gNB).

4. The method according to claim 1, wherein: The information is received based on the Sidelink Positioning Protocol (SLPP).

5. The method according to claim 1, further comprising: sending capability information about the AoD positioning method to a location server used to determine the positioning method, The capability information includes information about the maximum supported bandwidth.

6. The method according to claim 1, wherein: The location of the UE is determined based on Radio Access Technology (RAT) dependent positioning using a downlink reference signal and RAT-independent positioning using a Global Positioning System (GPS).

7. A user equipment (UE) in wireless communication, comprising: at least one transceiver; as well as At least one processor, coupled to at least one transceiver, configured to: receiving information about an angle of departure (AoD) positioning method, the information including direction information about each of a plurality of nodes and location information about each of the plurality of nodes, receiving downlink reference signals of a plurality of nodes from a plurality of nodes, determining the position of the UE based on the information about the AoD positioning method and a reference signal received power (RSRP) measurement of a downlink reference signal, and Sending the UE's location information and confidence information related to the accuracy to the location server, The direction information includes information on an angle associated with a reference direction that is geographically north.

8. The UE according to claim 7, wherein: The location of the UE is further determined based on at least one sensor including a gyroscope.

9. The UE according to claim 7, wherein: Multiple nodes are associated with the next generation nodeB (gNB).

10. The UE according to claim 7, wherein: The information is received based on the Sidelink Positioning Protocol (SLPP).

11. The UE according to claim 7, wherein: The at least one processor is further configured to: sending capability information about the AoD positioning method to a location server used to determine the positioning method, The capability information includes information about the maximum supported bandwidth.

12. The UE according to claim 7, wherein: The location of the UE is determined based on Radio Access Technology (RAT) dependent positioning using a downlink reference signal and RAT-independent positioning using a Global Positioning System (GPS).

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