WO2024141840A1 - Apparatuses and methods for positioning - Google Patents

Abstract

Embodiments of the present disclosure disclose a method and apparatus for uplink transmission power control. A first apparatus obtains a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands. The first apparatus further obtains array characteristic information and a beam configuration of at least one of the second apparatus or the third apparatus. Based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration, the first apparatus determines angular information. Then, the first apparatus determines positioning information of at least one of the third apparatus or the second apparatus based on the angular information. Therefore, positioning may be performed utilizing power measurements of signals, thereby enabling accurate positioning and improving communication efficiency and communication performance.

Description

APPARATUSES AND METHODS FOR POSITIONING

CROSS-REFERENCE TO RELATED APPLICATION:

[0001] This application claims the benefit of FI National Application No. 20226190, filed December 30, 2022. The entire content of the above-referenced application is hereby incorporated by reference.

FIELD

[0002] Embodiments of the present disclosure generally relate to the field of communication, and in particular, to apparatuses, methods, devices, and a computer readable storage medium for positioning.

BACKGROUND

[0003] With the development of communication technology, many of the services, e.g., enhance mobile broadband (eMBB), massive machine type communications (mMTC), ultrareliable low latency communications (uRLLC), etc. are quite demanding on high bandwidth, low-latency and ultra-reliability. Compared to the earlier generations, the support for new use cases, especially concerning various mission-critical applications, increases the requirements for positioning performance. Besides positioning accuracy, for example, latency and continuity of the positioning solution are considered key performance indicators. Besides positioning, efficient and practically feasible estimation of user equipment (UE) orientation using 5th generation (5G) new radio (NR) signals, is one of the remaining challenges.

[0004] 3rd Generation Partnership Project (3GPP) has started Release 18 (R18) work on expanding and improving NR-based positioning. Several new approaches, such as carrier phase based positioning, positioning reference signal (PRS)Zsounding reference signal (SRS) bandwidth aggregation, positioning of UEs with reduced capabilities, low power high accuracy positioning, and sidelink positioning, are presented and discussed with relevant integrity aspects of mission critical use cases. To fulfil the given requirements, new efficient methods for positioning and corresponding positioning-related measurements are needed. Positioning solutions suitable specifically for indoor environments are developed for Bluetooth and WiFi systems, for example, SUMMARY

[0005] In general, example embodiments of the present disclosure provide apparatuses, methods, devices, a computer readable storage medium, and computer programs for positioning.

[0006] In a first aspect, there is provided a first apparatus. The first apparatus may comprise at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus at least to: obtain a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands; obtain array characteristic information and a beam configuration of at least one of the second apparatus or the third apparatus; determine angular information based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration; and determine positioning information of at least one of the third apparatus or the second apparatus based on the angular information.

[0007] In a second aspect, there is provided a second apparatus. The second apparatus may comprise at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the second apparatus at least to: initiate, with a third apparatus, a positioning session for at least one of the second apparatus or the third apparatus; transmit, to the third apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmit, to a first apparatus, array characteristic information and a beam configuration of the second apparatus based on determining that an array of the second apparatus is configured with at least two antenna elements.

[0008] In a third aspect, there is provided a third apparatus. The third apparatus may comprise at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the third apparatus at least to: initiate, with a second apparatus, a positioning session for at least one of the second apparatus or the third apparatus; receive, from the second apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmit, to a first apparatus, array characteristic information and a beam configuration of the third apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements.

[0009] In a fourth aspect, there is provided a method implemented at a first apparatus. The method may comprise obtaining a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands; obtaining array characteristic information and a beam configuration of at least one of the second apparatus or the third apparatus; determining angular information based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration; and determining positioning information of at least one of the third apparatus or the second apparatus based on the angular information.

[0010] In a fifth aspect, there is provided a method implemented at a second apparatus. The method may comprise initiating, with a third apparatus, a positioning session for at least one of the second apparatus or the third apparatus; transmitting, to the third apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmitting, to a first apparatus, array characteristic information and a beam configuration of the second apparatus based on determining that an array of the second apparatus is configured with at least two antenna elements.

[0011] In a sixth aspect, there is provided a method implemented at a third apparatus . The method may comprise initiating, with a second apparatus, a positioning session for at least one of the second apparatus or the third apparatus; receiving, from the second apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmitting, to a first apparatus, array characteristic information and a beam configuration of the third apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements.

[0012] In a seventh aspect, there is provided a first apparatus. The first apparatus may comprise means for obtaining a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands; means for obtaining array characteristic information and a beam configuration of at least one of the second apparatus or the third apparatus; means for determining angular information based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration; and means for determining positioning information of at least one of the third apparatus or the second apparatus based on the angular information.

[0013] In an eighth aspect, there is provided a second apparatus. The second apparatus may comprise means for initiating, with a third apparatus, a positioning session for at least one of the second apparatus or the third apparatus; means for transmitting, to the third apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and means for transmitting, to a first apparatus, array characteristic information and a beam configuration of the second apparatus based on determining that an array of the second apparatus is configured with at least two antenna elements.

[0014] In a ninth aspect, there is provided a third apparatus. The third apparatus may comprise means for initiating, with a second apparatus, a positioning session for at least one of the second apparatus or the third apparatus; means for receiving, from the second apparatus, at least one predetermined signal for the positioning session on at least two subbands; and means for transmitting, to a first apparatus, array characteristic information and a beam configuration of the third apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements.

[0015] In a tenth aspect, there is provided a non-transitory computer readable medium comprising program instructions for causing an apparatus to perform at least the method according to any of fourth to six aspects.

[0016] In an eleventh aspect, there is provided a computer program comprising instructions, which, when executed by an apparatus, cause the apparatus at least to: obtain a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands; obtain array characteristic information and a beam configuration of at least one of the second apparatus or the third apparatus; determine angular information based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration; and determine positioning information of at least one of the third apparatus or the second apparatus based on the angular information.

[0017] In a twelfth aspect, there is provided a computer program comprising instructions, which, when executed by an apparatus, cause the apparatus at least to: initiate, with a third apparatus, a positioning session for at least one of the second apparatus or the third apparatus; transmit, to the third apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmit, to a first apparatus, array characteristic information and a beam configuration of the second apparatus based on determining that an array of the second apparatus is configured with at least two antenna elements.

[0018] In a thirteenth aspect, there is provided a computer program comprising instructions, which, when executed by an apparatus, cause the apparatus at least to: initiate, with a second apparatus, a positioning session for at least one of the second apparatus or the third apparatus; receive, from the second apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmit, to a first apparatus, array characteristic information and a beam configuration of the third apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements.

[0019] In a fourteenth aspect, there is provided a first apparatus. The first apparatus comprises obtaining circuitry configured to obtain a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands; obtaining circuitry configured to obtain array characteristic information and a beam configuration of at least one of the second apparatus or the third apparatus; determining circuitry configured to determine angular information based on the measurement report comprising the channel information of the at least two subbands, the array characteristic information, and the beam configuration; and determining circuitry configured to determine positioning information of at least one of the third apparatus or the second apparatus based on the angular information.

[0020] In a fifteenth aspect, there is provided a second apparatus. The second apparatus comprises initiating circuitry configured to initiate, with a third apparatus, a positioning session for at least one of the second apparatus or the third apparatus; transmitting circuitry configured to transmit, to the third apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmitting circuitry configured to transmit, to a first apparatus, array characteristic information and a beam configuration of the second apparatus based on determining that an array of the second apparatus is configured with at least two antenna elements.

[0021] In a sixteenth aspect, there is provided a third apparatus. The third apparatus comprises initiating circuitry configured to initiate, with a second apparatus, a positioning session for at least one of the second apparatus or the third apparatus; receiving circuitry configured to receive, from the second apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmitting circuitry configured to transmit, to a first apparatus, array characteristic information and a beam configuration of the third apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements.

[0022] It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Some example embodiments will now be described with reference to the accompanying drawings, in which:

[0024] Fig. 1 illustrates an example network environment in which example embodiments of the present disclosure may be implemented;

[0025] Fig. 2 illustrates a signaling chart illustrating an example process according to some embodiments of the present disclosure;

[0026] Fig. 3 illustrates an example of the beam power responses for different beamforming angles according to some embodiments of the present disclosure;

[0027] Fig. 4 illustrates an example angle estimation process according to some embodiments of the present disclosure;

[0028] Fig. 5 illustrates an example positioning process according to some embodiments of the present disclosure;

[0029] Fig. 6 illustrates another example positioning process according to some embodiments of the present disclosure;

[0030] Fig. 7 illustrates an example iterative Gauss-Newton process for a joint AOA and pathloss estimation according to some embodiments of the present disclosure;

[0031] Fig. 8 illustrates an example iterative Gauss-Newton process for a AOA and pathloss estimation separately according to some embodiments of the present disclosure;

[0032] Fig. 9 illustrates an example receive (RX) power spectrum with 3 separate carriers according to some embodiments of the present disclosure;

[0033] Fig. 10 illustrates an example function of beamforming angles in a single path scenario according to some embodiments of the present disclosure.

[0034] Fig. 11 illustrates likelihoods for the unknown parameters in a single path scenario according to some embodiments of the present disclosure.

[0035] Fig. 12 illustrates an example multipath scenario simulated in urban ray-tracing environment according to some embodiments of the present disclosure.

[0036] Fig. 13 illustrates an example function of beamforming angles in a multipath scenario according to some embodiments of the present disclosure.

[0037] Fig. 14 illustrates likelihoods for the unknown parameters in a multipath scenario according to some embodiments of the present disclosure.

[0038] Fig. 15 illustrates an example flowchart of a method implemented at a first apparatus according to some other embodiments of the present disclosure;

[0039] Fig. 16 illustrates an example flowchart of a method implemented at a second apparatus according to example embodiments of the present disclosure;

[0040] Fig. 17 illustrates an example flowchart of a method implemented at a third apparatus according to example embodiments of the present disclosure

[0041] Fig. 18 illustrates an example simplified block diagram of an apparatus that is suitable for implementing embodiments of the present disclosure; and

[0042] Fig. 19 illustrates an example block diagram of an example computer readable medium in accordance with some embodiments of the present disclosure.

[0043] Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

[0044] Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. The disclosure described herein may be implemented in various manners other than the ones described below.

[0045] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

[0046] References in the present disclosure to “one embodiment,” “an embodiment,” “an example embodiment,” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

[0047] It may be understood that although the terms “first” and “second” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the listed terms.

[0048] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “has”, “having”, “includes” and/or “including”, when used herein, specify the presence of stated features, elements, and/or components etc., but do not preclude the presence or addition of one or more other features, elements, components and/ or combinations thereof.

[0049] As used in this application, the term “circuitry” may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable):

(i) a combination of analog and/or digital hardware circuit(s) with software/firmware and (ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

(c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s) that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

[0050] This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0051] As used herein, the term “communication network” refers to a network following any suitable communication standards, such as long term evolution (LTE), LTE-advanced (LTE-A), wideband code division multiple access (WCDMA), high-speed packet access (HSPA), narrow band Internet of things (NB-IoT), Bluetooth, WI-FI, and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the third generation (3G), the fourth generation (4G), 4.5G, the fifth generation (5G) communication protocols, and/or beyond. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

[0052] As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP), for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), a NR NB (also referred to as a gNB), a remote radio unit (RRU), a radio header (RH), a remote radio head (RRH), a relay, a low power node such as a femto, a pico, and so forth, depending on the applied terminology and technology.

[0053] The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE), a subscriber station (SS), a portable subscriber station, a mobile station (MS), or an access terminal (AT). The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA), portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), USB dongles, smart devices, wireless customer-premises equipment (CPE), an Internet of things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. In the following description, the terms “terminal device”, “communication device”, “terminal”, “user equipment” and “UE” may be used interchangeably.

[0054] The term “transmitter”, “receiver”, and “operator” refer to any device that may be capable of wireless communication, and they are configured to communicate via wireless data communication links, and cooperate with a suitably configured RF antenna arrangement that can support a particular wireless communication protocol and modulation scheme. In some embodiments, the transmitter and the receiver are configured to support industry standards such as the Long Term Evolution (LTE) and emerging 5G standards, and the like. In the present disclosure, the “operator” further refers to any device that may be capable of performing position estimation. Transmitter, receiver, and operator may be contained in terminals or base stations separately, they may also be co-located in terminals or base stations. It is understood, however, that the present disclosure is not necessarily limited in application to a particular standard and associated protocols. Rather, the transmitter, receiver, and operator may be configured to support alternate, or additional, wireless data communication protocols, including future standards or variations thereof.

[0055] The term “AOA” refers to angle of arrival. AoA technology is may be used for indoor positioning. In addition, it may be used, for example, in 5G networks, e.g., in network nodes. The AoA technology is based on receivers and transmitters. For example, a device with a linear array of multiple antennas acts as a receiver and another device with a single antenna acts as a transmitter, assuming that radio waves behave as planar wave surfaces rather than spherical. If the transmitter sending the sine wave through the air is located on a normal line perpendicular to the array lines, then each antenna in the array will receive the same phase of the input signal. If the transmitter is not at the normal, the receiving antenna will measure the phase difference between the channels and use the phase difference information to estimate the angle of arrival.

[0056] The term “AOD” refers to angle of departure. For the AoD technology, the basic principle of measuring the phase difference is the same, but the roles of the devices are reversed. In AoD, the receiver can use a single antenna, while the transmitter uses multiple antennas. The transmitter switches the transmitting antennas sequentially, so that the receiving side understands the structure of the antenna array and switches the sequence.

[0057] AOA or AOD estimation is traditionally performed based on transmitting or receiving signals with an antenna array. Depending on the array implementation, the angle estimator can have access to different types of measurements. For example, in a fully digital antenna array, the array can be considered a sensor array, where each antenna element is able to process samples individually though separate digital signal processing chains. This enables utilization of traditional high accuracy angle estimation methods, such as MUSIC and ESPRIT. However, when considering mobile networks and devices with non-dedicated sensor arrays (e.g., gNBs and UEs), the number of parallel digital chains is, in practice, limited due to increased complexity and cost. Therefore, in many cases the arrays are based on hybrid implementation, including both digital and analog functionality. With analog antenna arrays, often referred to as phased arrays, a single sample summed over all elements with predefined phase shifts, is obtained at the time. This enables efficient antenna array implementation with good directivity and beamforming gain, but it limits the view of angles to the given beamforming direction after the desired beamformer has been applied. As a result, beam sweeping is required to scan the environment for obtaining information from different angles. [0058] AOD estimation and AOA estimation using beam sweeping is based on transmitting or receiving signals with different time -multiplexed beams. This type of procedure requires lots of time, and thus increases the estimation latency and system overhead, and reduces power efficiency. Typically, angle estimation using beam sweeping is based on beam-wise power measurements (i.e., one power measurement per beam) without the need of complexvalued measurements and associated phase information. This makes beam sweeping based angle estimation methods less subject to phase noise and other synchronization related errors compared to digital arrays. With beam sweeping, an angle estimate can be determined as the angle of the highest power beam or as a weighted mean of angles over multiple beam-wise power measurements (interpolation between beam angles). As a result, the angle estimation performance is strongly dependent on the number of training beams, and especially the separation (resolution) of beam angles. Thus, for beam-sweeping based angle estimation, there is the evident trade-off between the estimation accuracy and the number of used training beams. Consequently, good angle estimation performance can be achieved at the expense of increased latency, increased system overhead, and increased power consumption.

[0059] Therefore, according to embodiments of the present disclosure, there is provided a solution for positioning. In this solution, a first apparatus obtains a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands. The first apparatus further obtains array characteristic information and a beam configuration of at least one of the second apparatus or the third apparatus. Based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration, the first apparatus determines angular information. Then, the first apparatus determines positioning information of at least one of the third apparatus or the second apparatus based on the angular information. Therefore, positioning may be performed utilizing power measurements of signals. The phase noise the phase information may be ignored, and errors due to synchronization may be mitigated, thereby enabling accurate positioning and improving communication efficiency and communication performance.

[0060] Example embodiments of the present disclosure for beam alignment will be described below with reference to Figs. 1 to 19.

[0061] Fig. 1 illustrates an example network environment 100 in which example embodiments of the present disclosure may be implemented. The environment 100, which may be a part of a communication network, comprises terminal devices, network devices. As illustrated in Fig. 1, the communication network 100 may comprise a positioning server 110, a terminal device 120, and a network device 130. The network device 130 can manage a cell 101. The terminal device 120 and the network device 120 can communicate with each other in the coverage of the cell 101. The positioning server 110, the terminal device 120 and the network device 120 can communicate with each other, too.

[0062] In this disclosure, the first apparatus is used to refer to the device calculating the position, the second apparatus is used to refer to the device transmitting the signal, and the third device is used to refer to the device receiving the signal. The first apparatus may be a terminal device, a network device or a positioning server. The second apparatus may be a terminal device or a network device. The third apparatus may be a terminal device or a network device. These examples are described for the purpose of illustration and the disclosure is not limited to this.

[0063] It is to be understood that the number of positioning servers, network devices and terminal devices is for the purpose of illustration without suggesting any limitations. The system 100 may include any suitable number of network devices and terminal devices adapted for implementing embodiments of the present disclosure. Although not shown, it would be appreciated that one or more terminal devices may be located in the environment 100.

[0064] Communications in the network environment 100 may be implemented according to any proper communication protocol(s), comprising, but not limited to, the third generation (3G), the fourth generation (4G), the fifth generation (5G) or beyond, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: multiple-input multiple-output (MIMO), orthogonal frequency division multiplexing (OFDM), time division multiplexing (TDM), frequency division multiplexing (FDM), code division multiplexing (CDM), Bluetooth, ZigBee, and machine type communication (MTC), enhanced mobile broadband (eMBB), massive machine type communication (mMTC), ultra-reliable low latency communication (URLLC), carrier aggregation (CA), dual connection (DC), and new radio unlicensed (NR-U) technologies.

[0065] Fig. 2 illustrates a signaling chart illustrating an example process 200 according to some embodiments of the present disclosure. There are a first apparatus 201, a second apparatus 202 and a third apparatus 203 in Fig. 2. The first apparatus 201 may be corresponding to the positioning server 110 of Fig. 1, the second apparatus 202 may be a terminal device 120 of Fig. 1, and the third apparatus 203 may be a network device 130 of Fig. 1.

[0066] In some embodiments, the first apparatus, the third apparatus and the second apparatus may comprise at least one terminal device and at least one network device.

[0067] In some embodiments, the first apparatus may be co-located with one of the third apparatus and the second apparatus. In some embodiments, the first apparatus and the third apparatus may be the same apparatus or different apparatuses. It would be appreciated that although the example process 200 has been described referring to the network environment 100 of FIG. 1, this process flow 200 may be likewise applied to other similar communication scenarios.

[0068] As shown in Fig. 2, the second apparatus 202 initiates 207 a positioning session 212 with the third apparatus 203. The positioning session 212 is used for the second apparatus 202, the third apparatus 203, or both of them. Then the second apparatus 202 transmits 209 at least one predetermined signal 214 for the positioning session 212 on at least two sub-bands to the third apparatus 203. On another side of the communications, the third apparatus 203 initiates 205 a positioning session 212 with the second apparatus 202, and then the third apparatus 203 receives 211 at least one predetermined signal 214 for the positioning session 212 on at least two sub-bands from the second apparatus 202.

[0069] In some embodiments, the second apparatus 202 may perform 209 data transmission 214 with the third apparatus 203 during the positioning session 212. The second apparatus 202 may transmit a reference signal 218 to the third apparatus 203 via a physical uplink shared channel (PUSCH), a physical uplink control channel (PUCCH), a physical downlink shared channel (PDSCH) or a physical downlink control channel (PDCCH). In an example, the reference signal 218 may be a demodulation reference signal (DMRS).

[0070] In some embodiments, the third apparatus 303 may transmit 221 a schedule indication 220 indicating that scheduling additional reference signals on other frequencies or component carriers to the second apparatus. After receiving 223 the schedule indication from the third apparatus 303, the second apparatus 202 may transmit 225 the additional reference signals 222 to the third apparatus 203 in the same beam of the data transmission. Then the third apparatus 203 may receive 227 the additional reference signals 222 from the second apparatus 202.

[0071] In some embodiments, the second apparatus 202 may transmit a change indication 229 when the beam of the second apparatus to be change to the third apparatus 203. After receiving 231 the change indication, the third apparatus 203 may change the beam.

[0072] On yet another side of the communications, the first apparatus 201 obtains 233 a measurement report comprising channel information for at least one predetermined signal transmitted from the second apparatus 202. to the third apparatus 203 on at least two subbands.

[0073] In some embodiments, the measurement report may comprise a power measurement of the at least one predetermined signal of the at least two sub-bands for one or more beam; an amplitude measurement of the at least one predetermined signal of the at least two sub-bands for the one or more beam; a signal noise ratio (SNR) of the at least two sub-bands; or a signal to interference plus noise ratio (SINR) of the at least two sub-bands, or any combination of the above-mentioned items.

[0074] In some embodiments, the measurement report is determined in the first apparatus, the second apparatus, or the third apparatus, and the measurement report is transmitted between two different apparatuses.

[0075] Based on determining that an array of the second apparatus 202 is configured with at least two antenna elements, the second apparatus 202 transmits 235 array characteristic information and a beam configuration 226 of the second apparatus 202 to the first apparatus 201. Based on determining that an array of the third apparatus 203 is configured with at least two antenna elements, the third apparatus 203 transmits 239 array characteristic information and a beam configuration 228 of the third apparatus 203 to the first apparatus 201.

[0076] In some embodiments, the array characteristic information may comprise the number of antenna elements of the array; an antenna separation distance of the array; or information on an array gain function.

[0077] In some embodiments, the beam configuration may comprise beam direction and center frequency of one or more beam.

[0078] After receiving 237/241 the array characteristic information and a beam configuration of the second apparatus 202 and the third apparatus 203, the first apparatus 201 determines 243 angular information based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration.

[0079] In some embodiments, the angular information may comprise at least one of the following: path loss or an angle.

[0080] In some embodiments, the first apparatus 201 may determine the angular information by obtaining the angular information using an estimation model based on the measurement report, the array characteristic information, and the beam configuration.

[0081] In some embodiments, in obtaining the angular information using the estimation model, the first apparatus 201 may obtain a function of array gain based on the array characteristic information and beam configuration. In addition, the first apparatus 201 can obtain an error function between the array gain function and the power measurements of the at least one predetermined signal for one or more beam. Then, first apparatus 201 may determine the path loss and the angle by minimizing the error function.

[0082] In some embodiments, based on determining that the second beam is closer to the estimated angle than the first beam, the first apparatus 201 may determine 245 a beam switch by the third apparatus 203 from a first beam to a second beam. Then the first apparatus 201 may transmit 247 a switch indication 234 to the third apparatus 203. The switch indication 234 indicating the third apparatus 203 to perform the beam switch. After receiving witch indication 234 from the first apparatus 201, the third apparatus 203 may perform the beam switch from a first beam to a second beam based on the switch indication, wherein the second beam is closer to the estimated angle than the first beam.

[0083] Coming back to Fig. 2, the first apparatus 201 determines 251 positioning information of at least one of the third apparatus or the second apparatus based on the angular information.

[0084] In an example, the inventors consider a uniform linear array (ULA) antenna with phase -shifters (i.e., analog array) without loss of generality, and provide an example of a numerical analysis to 2D scenario with a single observable angle (azimuth or elevation). A signal is received using the ULA, which configured with a single beam pointing at angle p. Under these conditions, while assuming observing a single line of sight (LOS) path, it can be shown that the power spectral density of the received signal is given as:

[0085] where /is the frequency, is the AOA, is the path loss of the line of sight (LOS) path, and M is the number of antenna elements in the array. Furthermore,

[0086] where dant is the antenna separation distance of the ULA, c is the speed of light, and fc is a center frequency used to generate the beamformer (i.e., ULA phase-shifts for the used beam).

[0087] Fig. 3 illustrates an example of the beam power responses for different beamforming angles for AOA of 20 degrees according to some embodiments of the present disclosure. The power spectral density G(f, (j>, r/) of the received signal with A/=32 ULA is illustrated for different beamforming angles with a fixed AOA of /=20 deg. The assumed center frequency for the beamformer design is fc = 60 GHz. The figure shows that pointing the beam in different directions results in a frequency shift of the power spectral density.

[0088] Regarding the desired AOA estimation procedure, the unknown parameters are the AOA and path loss r/. These can be jointly estimated, for example, as:

{<; ., ?)} -- ar

[0089] where Y(k) is the measured signal at subcarrier k. The above equations can be essentially considered a non-linear least squares (LS) problem and the minimum can be found, for example, by using Gauss-Newton method.

[0090] Similarly, considering observations over multiple beams with beam indices b, the corresponding measured signal for beam b at subcarrier k can be defined as Yb(k), and the power spectral density of the received signal for beam b as Gb(f, (f> r/). In order to estimate the angle and the related path loss parameter r/ using multiple beams, the above-described non-linear LS problem becomes

[0091] Fig. 4 illustrates an example angle estimation process 400 according to some embodiments of the present disclosure. At block 410, for one or multiple beams index b. the operator obtains received power measurements

f_rom a set of subcarriers with subcarrier index k. At block 420, assuming known antenna array structure (i.e., number of antenna elements positions), the operator defines the analytic power spectral density for the bth beam as Gb(f r/). At block 430, the operator estimates the angle (AOD/AOA) and the related path loss parameter r/ by minimizing the least squares error over all beams as

.In some embodiments, an array of the third apparatus 203 may be configured with at least two antenna elements, then the first apparatus 201 may determine the positioning information of at least one of the second apparatus 202 or the third apparatus 203 with angle of arrival (AOA) estimation.

[0092] In some embodiments, an array of the second apparatus 202 is configured with at least two antenna elements, then the first apparatus 201 may determine the positioning information of at least one of the second apparatus 202 or the third apparatus 203 with angle of departure (AOD) estimation.

[0093] In some embodiments, beam gains, or the array gain function, of the at least two sub-bands for the at least one predetermined signal may be different.

[0094] In the current standard, angle estimation is specified only for the network side through the UL-AOA and DL-AOD methods. As discussed above, the proposed method enables also DL-AOA and UL-AOD with feasible UE side array configurations. In addition, UE-assisted and network-assisted methods for DL-AOA and UL-AOD can be configured accordingly.

[0095] In order to perform the proposed AOA or AOD estimation, the following information may be used: reference signal, including its time and frequency allocation array characteristics, such as array configuration, including the element geometry or array gain - beam configuration, including a beam direction ( ) and the considered center frequency (fc)

[0096] In Table 1, a brief summary of the example information and related signalling is described for different NR-based AOA positioning scenarios (UE-based, network-based, UE-assisted and network-assisted).

TABLE 1: Summary of different NR-based AOA positioning scenarios with examples of example information at the UE and network, as well as related signaling between the UE and network.

[0098] For illustrative purposes, Fig. 5 illustrates an example signaling process 500 according to some embodiments of the present disclosure. For the purpose of discussion, the signaling process 500 will be described with reference to FIG. 1. It would be appreciated that although the process flow 500 has been described referring to the network environment 100 of FIG. 1, this signaling process 500 may be likewise applied to other similar communication scenarios.

[0099] As one example, the main steps of a dedicated UL-AOA-based positioning procedure using the proposed angle estimation method is shown in Fig. 5. The steps focus on the radio access network (RAN), i.e., UE and gNB side, and neglect the core network functions and related signalling, for example, regarding LMF. The main steps of UL-AOA- based positioning procedure include:

[00100] A UE 501 may request 510 for localization to a LMF 503, a transmission and receiving point (TRP)/gNB 502 may also request 512 for localization to the LMF 503. Then the UE 501, the TRP/gNB 502 and the LMF 503 may start 514 a positioning session. The UE capabilities, assistance data, initial location may be communicated in the positioning session. At this point, if not yet available, a communication link between the network and UE is established. Therefore, the feasible beams/directions to be used for the upcoming AOA estimation may be communicated.

[00101] Then the TRP/gNB 502 informs the UE 501 regarding the transmission of SRS. The TRP/gNB 502 may transmit 516 an indication of used SRS resource allocations, for example, time resource and frequency resource. The TRP/gNB 502 may also request for 518 possible other transmission configuration, e.g., related to the UE-side beam configuration.

[00102] After that, the gNB or a set of gNBs (and/or related TRPs) 502 may receive 520 the uplink (UL) signals. The UL signals are received using at least 1 beam, but multiple beams can be used by properly scheduling the UE transmission. From the received signals, subcarrier-wise power measurements on the active reference signal subcarriers are obtained 522. the TRP/gNB 502 may transmit 524 power measurements to the LMF 503 via NR positioning protocol annex (NRPPa). Then the LMF 503 may estimate the location of the UE 501 or the TRP/gNB 502, then transmit the location to them.

[00103] Fig. 6 illustrates another example signaling process according to some embodiments of the present disclosure. For the purpose of discussion, the signaling process 600 will be described with reference to FIG. 1. It would be appreciated that although the process flow 600 has been described referring to the network environment 100 of FIG. 1, this signaling process 600 may be likewise applied to other similar communication scenarios.

[00104] As another example, we the main steps of the proposed method for network-side angle estimation using UL reference signals (such as DMRS) of an ongoing communications link in PUSCH/PUCCH are present in Fig. 6. Compared to the dedicated UL-AOA-based positioning scenario discussed above, here the angle estimation method does not require any dedicated positioning -associated beams, but the one used for the ongoing communications. Therefore, the method does not use any additional reference signals, which consequently minimizes the system overhead, energy consumption, and latency. In addition, the proposed AOA estimation can be used to steer the beam in time, and thus potentially avoid conventional beam training for the communications signal. This type of beam tracking is feasible, if the transmission intervals occur within the beam coverage, so that the SNR is enough to provide beamwidth level angle estimation accuracy. The main steps of the PUSCH/PUCCH (DMRS) associated AOA estimation include: [00105] Communications link between the UE 601, the TRP/gNB 602 and the LMF 603 is active. Transmissions occur in PUSCH and/or PDSCH during the session. The UE 601 has 610 an active connection with the network data transfer occurs in PUSCH and/or PDSCH, and PDSCH-related HARQ ACKS sent over PUCCH.

[00106] The UE 601 may request for localization to the TRP/gNB 602, and the TRP/gNB 602 may transmit 614 the request to the LMF 603. During the data transmission, the UE and the TRP/gNB 602 and the LMF 603 may start positioning session, and communicate UE capabilities, assistance data, initial location during the positioning session.

[00107] The TRP/gNB 602 performs PDSCH transmission with DMRS. In case of PDSCH- oriented transmission, the network can use the DMRS found in UL HARQ messages transmitted via PUCCH. With PUSCH-oriented transmission, the DMRS may be found as part of the scheduled user data resources. The UE 601 may perform 620 PUSCH/PUCCH transmission with DMRS at least for a single received beam. Then the TRP/gNB 602 obtains subcarrier-wise power measurements and estimation of AOA. The TRP/gNB 602 transmits a measurement report via NRPPa. The LMF 603 performs 623 estimation of the location. Then the LMF 603 transmits 628 indication of location information to the TRP/gNB 602, or transmits 630 indication of location information to the UE 601. The TRP/gNB 602 makes 632 a decision on beam-switiching based on the estimated AOA and currently used beam.

[00108] During the process, additional training data can be allocated for improving the performance. The TRP/gNB 602 transmits allocation for additional reference signals (e.g., SRS) on the same or different component carriers. The UE 601 UE might need to change its transmission beam, and transmits 636 an indication of the changed transmission beam.

[00109] In some examples, the gNB estimates the AOA using the subcarrier-wise power measurements and known characteristics of the receive array and related beam configurations. If the estimated AOA is closer to the direction of some other beam than the current beam, gNB can change the receive beam and continue from step 2. Otherwise, gNB can keep the current beam and continue from step 2.

[00110] During the session, the following triggering events might occur,

[00111] - For improving angle estimation accuracy, or resolving uncertain situations, gNB can schedule additional reference signals on other frequencies or component carriers. Based on the scheduling, UE includes additional frequency multiplexed reference signals in the data transmission (in the same or other component carriers). Transmission of all reference signals is performed using the same (analog) beam than with the data transmission

[00112] - UE needs to change its transmit beam. Depending on the earlier defined session configuration, UE might require to signal the beam change to the gNB.

[00113] One clear benefit of the proposed method is that it does not utilize phase information, but the amplitude or power of the received signals. Thus, the method is not subject to specific synchronization errors or phase noise, which can be substantially challenging especially at high carrier frequencies. In addition, because focusing on the power measurements, within a coherence time of a channel it is possible to combine measurements from different time instants and different component carriers without tight synchronization requirements. This makes the proposed method particularly suitable for carrier aggregation schemes, and thus for the new PRS/SRS bandwidth aggregation. In addition, the proposed method does not require contiguous allocation of subcarriers, or component carriers, so it is flexible for exploiting scattered frequency resources.

[00114] The proposed method can be used to estimate the AOA or AOD for both downlink (DL) and uplink (UL) signals. In practice, in many cases the assumed small UE array sizes limit the angle estimation accuracy at the UE. However, the proposed method enables improved accuracy over conventional analog-array-based angle estimation methods and offers a considerable alternative to high-cost digital arrays. In the proposed method, a poor performance of analog arrays with small number of array elements can be compensated by increasing the measurement bandwidth. This enables angle estimation also at the UE side, which would be advantageous, for example, to UE orientation estimation.

[00115] In order to discuss the influence of the number of beams on the positioning results, observations are performed on different numbers of beams in different scenarios. These will be discussed separately.

[00116] Example numerical results for a single beam observation

[00117] In order to illustrate the proposed method numerically, a LOS scenario (no multipath) is considered. In the LOS scenario, a ULA with M=16 antenna elements receives a signal using a single beam, pointing at [3=31.95 deg. The used carrier frequency is fc = 30 GHz, and there are 1000 observed subcarriers separated by 960kHz, which results in about 1 GHz bandwidth. The SNR is defined as 15 dB without the beam gain.

[00118] Fig. 7 illustrates an example iterative Gauss-Newton process for a joint AOA and pathloss estimation according to some embodiments of the present disclosure. As shown in Fig. 7, the x-axis refers to AOA, and the y-axis refers to normalized pathloss values. The circle refers to an initial value, the cross refers to a final value, and the line from the circle towards the cross refers to an iteration path. The black box indicates the truth value. The light contour indicates the square error, similar to a likelihood function, for a pair of AOA and normalized pathloss values. The true AOA and path loss values are about 26 degrees and 0.15 respectively. Despite of initializing the Gauss-newton process with considerably different parameter values compared to the true values, iterative estimation process results in a final estimate, located approximately at the true value.

[00119] Fig. 8 illustrates an example iterative Gauss-Newton process for a AOA and pathloss estimation separately according to some embodiments of the present disclosure. The x-axis refers to iteration number, the y-axis of top graph refers to path loss, y-axis of bottom graph refers to AOA It can be seen that both estimates converge consistently towards the true parameter values. It should be noted that the illustrated Gauss-Newton process is only one of the numerous possible methods to solve the given problem. By considering different variants of the Gauss-Newton algorithm, it is possible to affect the outcome. For example, the converge rate can be directly influenced by tuning a specific step-size parameter.

[00120] Example numerical results for a multiple beam observation

[00121] Similar to the above-presented single beam scenario, a LOS channel (no multipath) using the same ULA with M=16 antenna elements is considered. Instead of contiguous frequency allocation, the inventors assume 3 separate frequency allocations (similar to carrier aggregation) where the bandwidth of each allocation is about 12 MHz. For all frequency bands the subcarrier spacing is defined as 120kHz, and every 4th subcarrier contains a reference or pilot symbol used for the estimation. The SNR without the beam gain is determined roughly as 3 dB. An illustration of the received signal spectrum for the highest power beam is shown in Fig. 9, where also the used frequency allocation consisting of the 3 used frequency bands (each having about 12 MHz bandwidth) are clearly visible.

[00122] Fig. 10 illustrates an example function of beamforming angles for single path scenario according to some embodiments of the present disclosure. The x-axis refers to beam power, and the y-axis refers to azimuth. The true angle is shown with a dashed vertical line. For illustration purposes, in Fig. 10 the received signal power is presented for each beam (average power over all reference subcarriers). It should be emphasized that the proposed method may require only observing subcarrier powers of a single beam, and thus does not necessarily need beam sweeping over multiple beam angles. In Fig. 10 it is seen that the received beam powers are the largest for the two beams whose angles (31.95 degrees and 37.74 degrees) are closest to the true AOA (34.08 degrees). Now, instead of considering the highest power beam, the estimation is performed with the 2-3 highest power beams.

[00123] Assuming high SNR with beamforming gain, the distribution of noisy subcarrierwise power measurements can be approximated as Gaussian. When performing estimation with multiple beams, different beams have different SNRs, which can be taken into account in the estimation process. Assuming Gaussian distributed measurements, the overall likelihood can be given as a weighted sum over the square errors of different beams, where the weights are determined by the beam-wise SNRs.

[00124] Based on this, the AOA estimation results considering 1, 2 or 3 highest power beams is shown in Figure 11, where the approximate likelihoods are determined separately for each number of measured beams. The left x-axis refers to angle, the right x-axis refers to path loss scaling factor, and the y-axis refers to likelihoods. The true values are shown with the black vertical dashed lines. It can be seen that the likelihood is more accurate when using 2 or 3 beams compared to a single beam. However, it should be emphasized that the performance of the single beam approach is also very good, especially when recalling that there is no need to use a time-consuming beam sweeping procedure. Nonetheless, there is basically no difference between using 2 or 3 beams, which is reasonable, as the 3rd highest beam has significantly lower SNR compared to the two highest power beams, as seen earlier in Fig.10.

[00125] Example numerical results for a multiple beam observation in multipath scenario

[00126] In the above numerical examples, the single path channel (LOS) without effects of multipath propagation is considered. In the following, the proposed method is applied to a multipath channel using otherwise exactly the same simulation parameters than in the abovepresented numerical results for the multiple beam observation. The simulated channel is based on ray-tracing multipath profde in urban environment, as shown in Figure 12. The color of the path indicates the level of path power. The transmitter and receiver are in an open area with LOS connection. Multipath are observed through reflections, scattering and diffraction from the ground and surrounding buildings. In total 25 highest power paths are considered in the channel model.

[00127] Figure 13 presents the observed beam powers assuming a beam sweeping procedure. The x-axis refers to beam power, and the y-axis refers to azimuth. The LOS angle is shown with a dashed vertical line. It should be noticed that beam sweeping is not needed, but the beam powers are just shown for illustration purposes. Similar to the single-path case shown earlier in Figure 10, the two highest beam powers are found around the LOS path (in the above-presented single path case this was the only path in the model). However, due to multipath propagation, significant beam powers can be observed also in other paths with different AO A.

[00128] Fig. 14 illustrates likelihoods for the unknown parameters in a multipath scenario according to some embodiments of the present disclosure. The left x-axis refers to angle, the right x-axis refers to path loss scaling factor, and the y-axis refers to likelihoods. The true values, representing the LOS path, are shown with the black vertical dashed lines. In Fig. 14, the approximate likelihoods are determined separately for each number of measured beams in the multipath scenario. Compared to the earlier presented single path scenario, there is some incremental error in the estimation accuracy. However, as long as the AOA of the estimated path (here the LOS path) is the dominant path, the AOA estimation accuracy is not severely corrupted. In order to manage multipath propagation, the proposed method can be extended to estimate the AOAs of different multipaths for improved performance.

[00129] In this way, the proposed method provides a new technical effect that it may enable, e.g. , in contrast to beam sweeping -based solutions, AoD and AoA estimation by using power measurements based a single analog beam (while being applicable also with multiple beams), and meeting the requirements of low latency, low overhead and high power efficiency. In addition, the proposed method is based purely on power measurements, errors due to synchronization and phase noise are not decisive. Especially essential in carrier aggregation of reference signals (bandwidth aggregation of PRS/SRS). The proposed method may also be generalized to all phased-arrays that use phase -coherency between antenna elements to steer the beam pattern. Moreover, the proposed method provides procedure and signaling schemes for the following: Dedicated beam training schemes and related procedures and signaling; angles estimation during data transmissions (PUSCH/PUCCH) with related procedures and signaling; and carrier aggregation aspects.

[00130] Fig. 15 illustrates an example flowchart of a method 1500 implemented at a first apparatus 110 according to some other embodiments of the present disclosure. For the purpose of discussion, the method 1500 will be described from the perspective of the first apparatus 110 with reference to Fig. 1. It is to be understood that method 1500 may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

[00131] At block 1510, the first apparatus 110 obtains a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands.

[00132] At block 1520, the first apparatus 110 obtains array characteristic information and a beam configuration of the second apparatus or the third apparatus.

[00133] At block 1530, the first apparatus 110 determines angular information based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration.

[00134] At block 1540, the first apparatus 110 determines positioning information of the third apparatus or the second apparatus based on the angular information.

[00135] In some embodiments, the measurement report may comprise: a power measurement of the at least one predetermined signal of the at least two sub-bands for one or more beam; an amplitude measurement of the at least one predetermined signal of the at least two sub-bands for the one or more beam; a signal noise ratio (SNR) of the at least two sub-bands; or a signal to interference plus noise ratio (SINR) of the at least two sub-bands.

[00136] In some embodiments, the array characteristic information may comprise: the number of antenna elements of the array; an antenna separation distance of the array; or information on an array gain function. In some embodiments, the beam configuration may comprise beam direction and center frequency of one or more beam. In some embodiments, the angular information may comprise: path loss or an angle.

[00137] In some embodiments, the first apparatus may determine the angular information by obtaining the angular information using an estimation model based on the measurement report, the array characteristic information, and the beam configuration.

[00138] In some embodiments, the first apparatus may obtain the angular information using the estimation model by: obtaining a function of array gain based on the array characteristic information and beam configuration; obtaining an error function between the array gain function and the power measurements of the at least one predetermined signal for one or more beam; and determining the path loss and the angle by minimizing the error function.

[00139] In some embodiments, in determining the positioning information of the third apparatus or the second apparatus by the first apparatus may determining the positioning information with angle of arrival (AOA) estimation based on determining that an array of the third apparatus is configured with at least two antenna elements. The first apparatus may also determine the positioning information with angle of departure (AOD) estimation based on determining that an array of the second apparatus is configured with at least two antenna elements.

[00140] In some embodiments, the first apparatus may determine a beam switch by the third apparatus from a first beam to a second beam based on determining that the second beam is closer to the estimated angle than the first beam; and transmit, to the third apparatus, a switch indication indicating the third apparatus to perform the beam switch.

[00141] In some embodiments, the measurement report may be determined in the first apparatus, the second apparatus or the third apparatus, and the measurement report may be transmitted between two different apparatuses.

[00142] In some embodiments, the first apparatus may be co-located with the third apparatus or the second apparatus, or the first apparatus and the third apparatus are the same apparatus or different apparatuses.

[00143] In some embodiments, the first apparatus, the third apparatus and the second apparatus may comprise at least one terminal device and at least one network device.

[00144] In some embodiments, beam gains, or the array gain function, of the at least two sub-bands for the at least one predetermined signal may be different.

[00145] Fig. 16 illustrates an example flowchart of a method 1600 implemented at a second apparatus 120 according to some other embodiments of the present disclosure. For the purpose of discussion, the method 1600 will be described from the perspective of the first apparatus 110 with reference to Fig. 1. It is to be understood that method 1600 may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard. [00146] At block 1610, the second apparatus 120 initiates, with a third apparatus, a positioning session for the second apparatus or the third apparatus.

[00147] At block 1620, the second apparatus 120 transmits, to the third apparatus, at least one predetermined signal for the positioning session on at least two sub-bands

[00148] At block 1630, the second apparatus 120 transmits, to a first apparatus, array characteristic information and a beam configuration of the second apparatus based on determining that an array of the second apparatus is configured with at least two antenna elements.

[00149] In some embodiments, the array characteristic information may comprise one or more of: the number of antenna elements of the array; an antenna separation distance of the array; or information on an array gain function. In some embodiments, the beam configuration may comprise beam direction and center frequency of one or more beam.

[00150] In some embodiments, the second apparatus 120 may perform data transmission with the third apparatus during the positioning session; transmit a reference signal to the third apparatus. In some embodiments, the second apparatus 120 may receive, from the third apparatus, a schedule indication indicating that scheduling additional reference signals on other frequencies or component carriers; and transmit, to the third apparatus, the additional reference signals in the same beam of the data transmission. In some embodiments, the second apparatus 120 may transmit, to the third apparatus, a change indication when the beam of the second apparatus to be change.

[00151] In some embodiments, beam gains, or the array gain function, of the at least two sub-bands for the at least one predetermined signal may be different.

[00152] Fig. 17 illustrates an example flowchart of a method 1700 implemented at a third apparatus 130 according to some other embodiments of the present disclosure. For the purpose of discussion, the method 1700 will be described from the perspective of the third apparatus 130 with reference to Fig. 1. It is to be understood that method 1700 may further include additional blocks not shown and/or omit some shown blocks, and the scope of the present disclosure is not limited in this regard.

[00153] At block 1710, the third apparatus 130 initiates, with a second apparatus, a positioning session for the second apparatus or the third apparatus.

[00154] At block 1720, the third apparatus 130 receives, from the second apparatus, at least one predetermined signal for the positioning session on at least two sub-bands

[00155] At block 1730, the third apparatus 130 transmits, to a first apparatus, array characteristic information and a beam configuration of the third apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements.

[00156] In some embodiments, the third apparatus 130 may transmit the array characteristic information and the beam configuration of the third apparatus to the first apparatus 110 based on determining that an array of the third apparatus is configured with at least two antenna elements.

[00157] In some embodiments, the array characteristic information may comprise: the number of antenna elements of the array; an antenna separation distance of the array; or information on an array gain function. In some embodiments, the beam configuration may comprise beam direction and center frequency of one or more beam.

[00158] In some embodiments, the third apparatus 130 may perform data transmission with the second apparatus during the positioning session; and receive, from the second apparatus, a reference signal.

[00159] In some embodiments, the third apparatus 130 may receive, from the first apparatus, a switch indication indicating the third apparatus to perform a beam switch; and perform the beam switch from a first beam to a second beam based on the switch indication, wherein the second beam is closer to the estimated angle than the first beam.

[00160] In some embodiments, the third apparatus 130 may transmit, to the second apparatus, a schedule indication indicating that scheduling additional reference signals on other frequencies or component carriers; and receive, from the second apparatus, the additional reference signals in the same beam of the data transmission.

[00161] In some embodiments, the third apparatus 130 may receive, from the second apparatus 120, a change indication indicating the beam of the second apparatus to be change.

[00162] In some embodiments, an apparatus capable of performing any of the method 1500 (for example, the first apparatus 110) is provided. The apparatus may comprise means for performing the respective steps of the method 1500. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. [00163] In some embodiments, the apparatus comprises: means for obtaining, at a first apparatus, a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands; means for obtaining array characteristic information and a beam configuration of the second apparatus or the third apparatus; means for determining angular information based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration; and means for determining positioning information of the third apparatus or the second apparatus based on the angular information.

[00164] In some embodiments, the measurement report may comprise: a power measurement of the at least one predetermined signal of the at least two sub-bands for one or more beam; an amplitude measurement of the at least one predetermined signal of the at least two sub-bands for the one or more beam; a signal noise ratio (SNR) of the at least two sub-bands; or a signal to interference plus noise ratio (SINR) of the at least two sub-bands.

[00165] In some embodiments, the array characteristic information may comprise: the number of antenna elements of the array; an antenna separation distance of the array; or information on an array gain function. In some embodiments, the beam configuration may comprise beam direction and center frequency of one or more beam. In some embodiments, the angular information may comprise the following: path loss or an angle.

[00166] In some embodiments, means for determining the angular information may comprise: means for obtaining the angular information using an estimation model based on the measurement report, the array characteristic information, and the beam configuration.

[00167] In some embodiments, means for obtaining the angular information using the estimation model may comprise: means for obtaining a function of array gain based on the array characteristic information and beam configuration; means for obtaining an error function between the array gain function and the power measurements of the at least one predetermined signal for one or more beam; and means for determining the path loss and the angle by minimizing the error function.

[00168] In some embodiments, means for determining the positioning information of the third apparatus or the second apparatus may comprise: means for determining the positioning information with angle of arrival (AOA) estimation based on determining that an array of the third apparatus is configured with at least two antenna elements; or means for determining the positioning information with angle of departure (AOD) estimation based on determining that an array of the second apparatus is configured with at least two antenna elements.

[00169] In some embodiments, the apparatus may comprise: means for determining a beam switch by the third apparatus from a first beam to a second beam based on determining that the second beam is closer to the estimated angle than the first beam; and means for transmitting, to the third apparatus, a switch indication indicating the third apparatus to perform the beam switch.

[00170] In some embodiments, the measurement report may be determined in the first apparatus, the second apparatus or the third apparatus, and the measurement report may be transmitted between two different apparatuses.

[00171] In some embodiments, the first apparatus may be co-located with one of the third apparatus and the second apparatus, or the first apparatus and the third apparatus are the same apparatus or different apparatuses.

[00172] In some embodiments, the first apparatus, the third apparatus and the second apparatus may comprise at least one terminal device and at least one network device.

[00173] In some embodiments, beam gains, or the array gain function, of the at least two sub-bands for the at least one predetermined signal may be different.

[00174] In some embodiments, the apparatus further comprises means for performing other steps in some example embodiments of the method 1500. In some example embodiments, the means comprises at least one processor and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the apparatus.

[00175] In some embodiments, an apparatus capable of performing any of the method 1600 (for example, the second apparatus 120) is provided. The apparatus may comprise means for performing the respective steps of the method 1600. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

[00176] In some embodiments, the apparatus comprises: means for initiating, with a third apparatus, a positioning session for at least one of the second apparatus or the third apparatus; means for transmitting, to the third apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and means for transmitting, to a first apparatus, array characteristic information and a beam configuration of the second apparatus based on determining that an array of the second apparatus is configured with at least two antenna elements.

[00177] In some embodiments, the array characteristic information may comprise one or more of: the number of antenna elements of the array; an antenna separation distance of the array; or information on an array gain function. In some embodiments, the beam configuration may comprise beam direction and center frequency of one or more beam.

[00178] In some embodiments, the apparatus may comprise: means for performing data transmission with the third apparatus during the positioning session; means for transmitting a reference signal to the third apparatus; means for receiving, from the third apparatus, a schedule indication indicating that scheduling additional reference signals on other frequencies or component carriers; and means for transmitting, to the third apparatus, the additional reference signals in the same beam of the data transmission, means for transmitting, to the third apparatus, a change indication when the beam of the second apparatus to be change.

[00179] In some embodiments, beam gains, or the array gain function, of the at least two sub-bands for the at least one predetermined signal may be different.

[00180] In some embodiments, the apparatus further comprises means for performing other steps in some embodiments of the method 1600. In some embodiments, the means comprises at least one processor and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the apparatus.

[00181] In some embodiments, an apparatus capable of performing any of the method 1700 (for example, the third apparatus 130) is provided. The apparatus may comprise means for performing the respective steps of the method 1700. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module.

[00182] In some embodiments, the apparatus comprises: means for initiating, with a second apparatus, a positioning session for at least one of the second apparatus or the third apparatus; means for receiving, from the second apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and means for transmitting, to a first apparatus, array characteristic information and a beam configuration of the third apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements.

[00183] In some embodiments, the apparatus may comprise: means for transmitting at least one of the array characteristic information and the beam configuration of the third apparatus to the first apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements.

[00184] In some embodiments, the array characteristic information may comprise one or more of: the number of antenna elements of the array; an antenna separation distance of the array; or information on an array gain function. In some embodiments, the beam configuration may comprise beam direction and center frequency of one or more beam.

[00185] In some embodiments, the apparatus may comprise: means for performing data transmission with the second apparatus during the positioning session; and means for receiving, from the second apparatus, a reference signal.

[00186] In some embodiments, the apparatus may comprise: means for receiving, from the first apparatus, a switch indication indicating the third apparatus to perform a beam switch; and means for performing the beam switch from a first beam to a second beam based on the switch indication, wherein the second beam is closer to the estimated angle than the first beam.

[00187] In some embodiments, the apparatus may comprise: means for transmitting, to the second apparatus, a schedule indication indicating that scheduling additional reference signals on other frequencies or component carriers; and means for receiving, from the second apparatus, the additional reference signals in the same beam of the data transmission.

[00188] In some embodiments, the apparatus may comprise: means for receiving, from the second apparatus, a change indication indicating the beam of the second apparatus to be change.

[00189] In some embodiments, the apparatus further comprises means for performing other steps in some example embodiments of the method 1700. In some example embodiments, the means comprises at least one processor and at least one memory including computer program code, the at least one memory and computer program code configured to, with the at least one processor, cause the performance of the apparatus.

[00190] Fig. 18 is a simplified block diagram of a device 1800 that is suitable for implementing embodiments of the present disclosure. The device 1800 may be provided to implement the communication device, for example the first apparatus 110, the second apparatus 120, and the third apparatus 130 as shown in Fig. 1. As shown, the device 1800 includes one or more processors 1810, and one or more communication modules 1840 coupled to the processor 1810. The device 1800 may further include one or more memories 1820 coupled to the processor 1810. The device 1800 may further include one or more memory 1820 storing instructions coupled to the one or more processors 1810.

[00191] The communication module 1840 may be for bidirectional communications. The communication module 1840 has at least one antenna to facilitate communication. The communication interface may represent any interface that is necessary for communication with other network elements.

[00192] The processor 1810 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 1800 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

[00193] The communication module 1840 may include for example one or more transceivers. The one or more transceivers may be coupled with one or more antennas, to wirelessly transmit and receive communication signals. The one or more transceivers allow the communication device to communicate with other devices that may be wired and/or wireless. The transceiver may support one or more radio technologies. For example, the one or more transceivers may include a cellular subsystem, a WLAN subsystem, and/or a Bluetooth™ subsystem. In some examples, the one or more transceivers may include processors, controllers, radios, sockets, plugs, buffers, and like circuits/devices used for connecting to and communication on networks.

[00194] The memory 1820 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a Read Only Memory (ROM) 1824, an electrically programmable read only memory (EPROM), a flash memory, a hard disk, a compact disc (CD), a digital video disk (DVD), and other magnetic storage and/or optical storage. Examples of the volatile memories include, but are not limited to, a random access memory (RAM) 1822 and other volatile memories that will not last in the power-down duration.

[00195] A computer program 1830 includes computer executable instructions that are executed by the associated processor 610. The program 1830 may be stored in the ROM 1824. The processor 1810 may perform any suitable actions and processing by loading the program 1830 into the RAM 1822.

[00196] The embodiments of the present disclosure may be implemented by means of the program 1830 so that the device 1800 may perform any process of the disclosure as discussed with reference to Figs. 2 to 15. The embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

[00197] In some embodiments, the program 1830 may be tangibly contained in a computer readable medium which may be included in the device 1800 (such as in the memory 1820) or other storage devices that are accessible by the device 1800. The device 1800 may load the program 1830 from the computer readable medium to the RAM 1822 for execution. The computer readable medium may include any types of tangible non-volatile storage, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and the like. Fig. 19 shows an example of the computer readable medium 1900 in form of CD or DVD. The computer readable medium has the program 1830 stored thereon.

[00198] Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

[00199] The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the method 1500, 1600 or 1700 as described above with reference to Fig.15, Fig.16 or Fig.17. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine -executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

[00200] Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

[00201] In the context of the present disclosure, the computer program codes or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable medium, and the like.

[00202] The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[00203] Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

[00204] Although the present disclosure has been described in languages specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

WHAT IS CLAIMED IS:

1. A first apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus at least to: obtain a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands; obtain array characteristic information and a beam configuration of at least one of the second apparatus or the third apparatus; determine angular information based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration; and determine positioning information of at least one of the third apparatus or the second apparatus based on the angular information.

2. The first apparatus of claim 1, wherein the measurement report comprises at least one of: a power measurement of the at least one predetermined signal of the at least two subbands for one or more beam; an amplitude measurement of the at least one predetermined signal of the at least two sub-bands for the one or more beam; a signal noise ratio (SNR) of the at least two sub-bands; or a signal to interference plus noise ratio (SINR) of the at least two sub-bands.

3. The first apparatus of claim 1, wherein: the array characteristic information comprises at least one of: the number of antenna elements of the array; an antenna separation distance of the array; or information on an array gain function; and the beam configuration comprises beam direction and center frequency of one or more beam; and the angular information comprises at least one of the following: path loss or an angle.

4. The first apparatus of any of claims 1-3, wherein the first apparatus is caused to determine the angular information by: obtaining the angular information using an estimation model based on the measurement report, the array characteristic information, and the beam configuration.

5. The first apparatus of claim 4, wherein the first apparatus is caused to obtain the angular information using the estimation model by: obtaining a function of array gain based on the array characteristic information and beam configuration; obtaining an error function between the array gain function and the power measurements of the at least one predetermined signal for one or more beam; and determining the path loss and the angle by minimizing the error function.

6. The first apparatus of any of claims 1-5, wherein the first apparatus is caused to determine the positioning information of at least one of the third apparatus or the second apparatus by at least one of: determining the positioning information with angle of arrival (AOA) estimation based on determining that an array of the third apparatus is configured with at least two antenna elements; or determining the positioning information with angle of departure (AOD) estimation based on determining that an array of the second apparatus is configured with at least two antenna elements.

7. The first apparatus of any of claims 1-6, wherein the first apparatus is further caused to: determine a beam switch by the third apparatus from a first beam to a second beam based on determining that the second beam is closer to the estimated angle than the first beam; and transmit, to the third apparatus, a switch indication indicating the third apparatus to perform the beam switch.

8. The first apparatus of any of claims 1-7, wherein: the measurement report is determined in at least one of the first apparatus, the second apparatus or the third apparatus, and the measurement report is transmitted between two different apparatuses.

9. The first apparatus of any of claims 1-8, wherein: the first apparatus is co-located with one of the third apparatus and the second apparatus, or the first apparatus and the third apparatus are the same apparatus or different apparatuses.

10. The first apparatus of any of claims 1-9, wherein the first apparatus, the third apparatus and the second apparatus comprise at least one terminal device and at least one network device.

11. The first apparatus of any of claims 1-10, wherein beam gains, or the array gain function, of the at least two sub-bands for the at least one predetermined signal are different.

12. A second apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the second apparatus at least to: initiate, with a third apparatus, a positioning session for at least one of the second apparatus or the third apparatus; transmit, to the third apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmit, to a first apparatus, array characteristic information and a beam configuration of the second apparatus based on determining that an array of the second apparatus is configured with at least two antenna elements.

13. The second apparatus of claim 12, wherein: the array characteristic information comprises one or more of: the number of antenna elements of the array; an antenna separation distance of the array; or information on an array gain function; and the beam configuration comprises beam direction and center frequency of one or more beam.

14. The second apparatus of claim 12, wherein the second apparatus is further caused to perform at least one of the following: perform data transmission with the third apparatus during the positioning session; transmit, to the third apparatus, a reference signal ; receive, from the third apparatus, a schedule indication indicating that scheduling additional reference signals on other frequencies or component carriers; and transmit, to the third apparatus, the additional reference signals in the same beam of the data transmission; or transmit, to the third apparatus, a change indication when the beam of the second apparatus to be change.

15. The second apparatus of any of claims 12-14, wherein beam gains, or the array gain function, of the at least two sub-bands for the at least one predetermined signal are different.

16. A third apparatus comprising : at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the third apparatus at least to: initiate, with a second apparatus, a positioning session for at least one of the second apparatus or the third apparatus; receive, from the second apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmit, to a first apparatus, array characteristic information and a beam configuration of the third apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements.

17. The third apparatus of claim 16, the third apparatus is caused to transmit at least one of the array characteristic information and the beam configuration of the third apparatus to the first apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements, wherein: the array characteristic information comprises at least one of: the number of antenna elements of the array; an antenna separation distance of the array; or information on an array gain function; and the beam configuration comprises beam direction and center frequency of one or more beam.

18. The third apparatus of claim 17, wherein the third apparatus is further caused to perform at least one of the following: perform data transmission with the second apparatus during the positioning session; and receive, from the second apparatus, a reference signal; or receive, from the first apparatus, a switch indication indicating the third apparatus to perform a beam switch; and perform the beam switch from a first beam to a second beam based on the switch indication, wherein the second beam is closer to the estimated angle than the first beam; or transmit, to the second apparatus, a schedule indication indicating that scheduling additional reference signals on other frequencies or component carriers; and receive, from the second apparatus, the additional reference signals in the same beam of the data transmission; or receive, from the second apparatus, a change indication indicating the beam of the second apparatus to be change.

19. A method comprising: obtaining, at a first apparatus, a measurement report comprising channel information for at least one predetermined signal transmitted from a second apparatus to a third apparatus on at least two sub-bands; obtaining array characteristic information and a beam configuration of at least one of the second apparatus or the third apparatus; determining angular information based on the measurement report comprising the channel information of the at least two sub-bands, the array characteristic information, and the beam configuration; and determining positioning information of at least one of the third apparatus or the second apparatus based on the angular information.

20. A method comprising: initiating, at a second apparatus with a third apparatus, a positioning session for at least one of the second apparatus or the third apparatus; transmitting, to the third apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmitting, to a first apparatus, array characteristic information and a beam configuration of the second apparatus based on determining that an array of the second apparatus is configured with at least two antenna elements.

21. A method comprising: initiating, at a third apparatus with a second apparatus, a positioning session for at least one of the second apparatus or the third apparatus; receiving, from the second apparatus, at least one predetermined signal for the positioning session on at least two sub-bands; and transmitting, to a first apparatus, array characteristic information and a beam configuration of the third apparatus based on determining that an array of the third apparatus is configured with at least two antenna elements.

22. A non-transitory computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to perform at least the method of any of claims 19-21.