Device and method for determination of timing information in wireless communication networks
By aligning transmission times of reference signals using AI/ML models to calculate timing-related information, the system addresses inaccuracies in UE positioning under NLOS conditions, improving positioning accuracy and reliability in complex environments.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- HUAWEI TECH CO LTD
- Filing Date
- 2024-11-08
- Publication Date
- 2026-05-15
AI Technical Summary
Existing wireless communication systems face challenges in accurately positioning user equipment (UE) under non-line-of-sight (NLOS) conditions due to signal reflections and diffractions, leading to inaccurate position estimates, and there is a lack of alignment in the processing of intermediate parameters across different network entities.
A mechanism is introduced to enhance positioning accuracy by aligning the transmission times of reference signals across different network entities, using AI/ML models to calculate timing-related information such as TOF, propagation delay, and RTOA, and ensuring consistent reporting of these values to improve positioning systems.
This approach improves the accuracy and reliability of UE positioning, especially in complex environments, by ensuring aligned timing information is shared across network entities, thereby enhancing the precision of location-based services.
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Figure CN2024130881_15052026_PF_FP_ABST
Abstract
Description
DEVICE AND METHOD FOR DETERMINATION OF TIMING INFORMATION IN WIRELESS COMMUNICATION NETWORKSTECHNICAL FIELD
[0001] The present disclosure relates to wireless communication systems, particularly in the context of new radio (NR) technologies. Specifically, it pertains to the application of artificial intelligence (AI) and machine learning (ML) techniques for enhancing the positioning accuracy of user equipment (UE) , particularly in scenarios involving non-line-of-sight (NLOS) conditions between transmission and reception points (TRPs) and the UE.BACKGROUND
[0002] Positioning of UE is crucial in modern wireless networks, particularly for applications that require high precision, such as navigation, autonomous systems, and location-based services. Traditional methods of positioning, such as time of arrival (TOA) , time difference of arrival (TDOA) , and angle of arrival (AOA) , rely on clear line-of-sight (LOS) between the UE and the TRPs. However, in complex urban or indoor environments, these signals often face obstructions, resulting in NLOS conditions that degrade positioning accuracy.
[0003] Under NLOS conditions, the performance of traditional positioning methods is significantly degraded due to signal reflections and diffractions, resulting in inaccurate position estimates. To overcome these limitations, the 3rd Generation Partnership Project (3GPP) has investigated the use of AI / ML techniques to enhance positioning in 5G NR systems. By analyzing channel measurements obtained through reference signals transmitted between a UE and one or more transmission points, AI / ML models can be trained to either directly estimate the UE's position or assist in determining intermediate parameters, such as time of flight (TOF) or LOS / NLOS conditions.
[0004] AI / ML-based positioning can be categorized into two approaches:
[0005] Direct AI / ML Positioning: In this method, AI / ML models are trained to directly infer the position of the UE using channel measurements, such as received signal strength and timing information, from multiple TRPs.
[0006] AI / ML-Assisted Positioning: Here, AI / ML models are trained to estimate intermediate parameters (e.g., TOF, TDOA, RTOA or LOS / NLOS indicators) that can then be used by conventional positioning algorithms to determine the UE’s location. The calculated intermediate parameters may need to be processed further before being sent to the location management function (LMF) , where the UE’s location can be determined.
[0007] Both approaches rely on channel measurements collected at either the UE or gNB, based on reference signals transmitted over the network. Uplink-based positioning uses Sounding Reference Signals (SRS) transmitted by the UE and received by the gNB, while downlink-based positioning relies on Positioning Reference Signals (PRS) transmitted by the gNB and received by the UE. The model training can take place at different nodes, including the UE, gNB, or an LMF. The positioning process can take place at the LMF.
[0008] Despite the potential of AI / ML techniques, their integration into existing positioning systems faces challenges, particularly that the further processing of the calculated intermediate parameters needs to be aligned across the UE, gNB and LMF. Without this alignment or common understanding on the reported values, the estimation of the UE location may be erroneous.SUMMARY
[0009] In view of the above challenges, an objective of this disclosure is to introduce a mechanism to enhance the accuracy and reliability of positioning systems in modern wireless networks, particularly addressing the critical issue of the common understanding on the reported values between the UE, gNB and / or LMF. One objective is to ensure the alignment of the transmission (Tx) times of reference signals across different network entities for determining a value to be reported based on the calculated timing value. By addressing such alignment issues inherent in the positioning process, the application aims to improve the overall accuracy of positioning systems, thus paving the way for more reliable and efficient location-based services in next-generation wireless communication networks.
[0010] These and other objectives are achieved by the solution of the present disclosure as provided in the independent claims. Advantageous implementations are further defined in the dependent claims.
[0011] A first aspect of the disclosure provides an entity for a wireless communication system, the entity being configured to: receive a first reference signal, determine timing information related to the first reference signal, based on one or more calculated timing values associated with the first reference signal and a designated transmit (Tx) time of the first reference signal, and provide the timing information related to the first reference signal to a network entity.
[0012] This disclosure accordingly proposes an entity or device that determines timing-related information by calculating values associated with a reference signal and a designated Tx time of the reference signal. For instance, the first reference signal can be transmitted by another entity and received by the entity, i.e., via multiple TRPs that belong to the gNB. The first reference signal can also be received by other gNBs, i.e., via multiple TRPs belonging to the other gNBs. The approach ensures aligned timing-related information based on the calculated timing values across different entities, enhancing the accuracy of the positioning. By providing this information to a network entity, such as an LMF, the system can optimize positioning performance, especially in scenarios involving measurements from multiple gNBs and / or UEs.
[0013] In an implementation form of the first aspect, the entity is further configured to receive a request from the network entity, wherein the request indicates the entity to provide the timing-related information associated with the first reference signal.
[0014] This disclosure allows for a flexible interaction between the network entity and the device, ensuring that timing-related information is provided upon request. This facilitates an on-demand exchange of data, ensuring that the network entity has access to the necessary information when needed for positioning calculations.
[0015] In an implementation form of the first aspect, the entity is further configured to receive the designated Tx time of the first reference signal from the network entity.
[0016] This feature ensures that the Tx time of the first reference signal assumed for the determination of the timing-related information is aligned with the network entity. The timing transfer improves the overall performance of positioning systems by reducing discrepancies between the entity and the network entity.
[0017] In an implementation form of the first aspect, the entity is further configured to determine the designated Tx time of the first reference signal, and indicate the designated Tx time of the first reference signal to the network entity.
[0018] This aspect allows the entity to autonomously determine the designated Tx time and communicate it to the network entity, enabling greater flexibility in scenarios where the network entity does not provide this information. This enhances the adaptability of the system in different network configurations.
[0019] In an implementation form of the first aspect, the one or more calculated timing values include a calculated TOF, a calculated propagation delay, or a calculated relative time of arrival (RTOA) .
[0020] The inclusion of TOF, propagation delay, and RTOA as calculated timing values enables precise measurements of signal propagation time, which is critical for determining the distance between the user equipment and the base station. This ensures accurate positioning, particularly in complex environments with multiple paths and signal reflections. Furthermore, a calculated value, i.e., calculated TOF, can also be referred to as inferred, predicted, virtual, non-measured, deduced, estimated, or derived value in this application. The one or more calculated timing value associated with the first reference signal can be obtained based on measurements of the first reference signal, e.g., based on measurements at one or more TRPs of a gNB. The calculated timing value can be obtained based on fingerprints of measurements of the first reference signal. The one or more calculated timing values can be associated with one or more TRPs.
[0021] In an implementation form of the first aspect, the entity is further configured to generate the one or more calculated timing values using a model trained to infer timing information related to the first reference signal.
[0022] By leveraging a model trained to infer one or more calculated timing values, the system benefits from enhanced precision and adaptability in various signal conditions. This allows for better handling of multipath propagation and other signal distortions, leading to more reliable timing measurements.
[0023] In an implementation form of the first aspect, the input of the model is based on measurements of the first reference signal.
[0024] For instance, if the entity is a gNB, the input measurements may include those being measured at one or more further entities (i.e., TRPs) that belong to the gNB.
[0025] In an implementation form of the first aspect, the timing information comprises: an uplink relative time of arrival (UL RTOA) , a downlink reference signal time difference (DL RSTD) , a round trip time (RTT) , or a Rx-Tx time difference.
[0026] The inclusion of various timing metrics allows the system to cover a wide range of measurement reports that can be sent from the entity to the network entity to support positioning based on uplink and downlink signals. This flexibility ensures that the entity can support a comprehensive set of positioning use cases, improving system performance in different environments. The timing information can comprise one or more UL RTOA values; or one or more DL RSTD values. The one or more UL RTOAs or the one or more DL RSTDs can be associated with one or more TRPs. The timing information can comprise one or more UE Rx-Tx time differences; or one or more gNB Rx-Tx time differences. The one or more UE Rx-Tx time differences or the one or more gNB Rx-Tx time differences can be associated with one or more TRPs.
[0027] In an implementation form of the first aspect, the entity is further configured to transmit a second reference signal, and determine the timing information based on a designated Tx time of the second reference signal.
[0028] By enabling the entity to transmit a second reference signal and further determine timing information based on its designated Tx time, this configuration improves bidirectional timing alignment. This leads to common understanding of the Tx time that should be considered at different entities, i.e., UE and gNB, which is especially beneficial for precise positioning measurements.
[0029] In an implementation form of the first aspect, the entity is further configured to receive the designated Tx time of the second reference signal from the network entity.
[0030] Allowing the entity to receive the designated Tx time of the second reference signal from the network entity enhances flexibility in the alignment of the Tx time across network devices. This allows the network entity to have a common understanding with multiple entities allowing to support positioning based on uplink and downlink signals. Consequently, positioning accuracy improves, even in challenging scenarios such as urban areas with dense infrastructure or indoor areas with dense multipath.
[0031] In an implementation form of the first aspect, the entity is further configured to: determine the designated Tx time of the second reference signal, and indicate the designated Tx time of the second reference signal to the network entity.
[0032] This configuration supports bidirectional coordination between the entity and the network entity, enabling dynamic adjustments to Tx times. Such an approach ensures seamless alignment of the assumed Tx timing between the network and device, further enhancing the reliability and precision of timing-based measurements.
[0033] In an implementation form of the first aspect, the first reference signal comprises a SRS or a PRS, and / or the second reference signal comprises a PRS or a SRS.
[0034] This feature ensures that the entity can handle both SRS and PRS, which are commonly used in positioning systems. By supporting both types of signals, the system enhances its versatility in a range of applications, based on uplink measurements and / or downlink measurements.
[0035] In an implementation form of the first aspect, the entity is one of the following: a base station, a TRP, a gNB, a position reference unit (PRU) , or a UE.
[0036] Possibly, the proposed entity may be implemented in a gNB, a TRP, a PRU, or a UE, which have the capability of receiving reference signals as part of their implementation of the relevant specification. Notably, this disclosure is applicable to various types of network devices, increasing its flexibility and utility in different wireless communication environments.
[0037] A second aspect of the disclosure provides a network entity in a wireless communication system, configured to obtain timing information related to a first reference signal from an entity, wherein the timing information is based on one or more calculated timing values associated with the first reference signal and a designated Tx time of the first reference signal.
[0038] This disclosure proposes a network entity that coordinates the collection of timing-related information from the entity. By obtaining this information, the network entity can make more accurate positioning calculations, leading to improved system-wide UE localization. With the reported timing information, the network entity may perform AI-based positioning with the provided timing-related information, or train a model for AI-based positioning. Possibly, the network entity may be the LMF. The network entity may obtain timing information from a plurality of entities. For instance, the LMF may request multiple gNB to obtain a calculated UL RTOA based on SRS sent by the UE.
[0039] In an implementation form of the second aspect, the network entity is further configured to send a request to the entity, wherein the request specifies that the entity to provide the timing information related to the first reference signal.
[0040] This feature enables the network entity to manage the timing information it receives, ensuring that data is only transmitted when required, thereby improving the efficiency of communication between the network entity and the device. Possibly, the network entity may send request to more than one entity, and request timing information from each of them.
[0041] In an implementation form of the second aspect, the network entity is further configured to provide the designated Tx time of the first reference signal to the entity or receive the designated Tx time of the first reference signal from the entity.
[0042] This ensures that the network entity can either supply or receive the designated Tx time, allowing it to have a common understanding about the Tx time with the device and thereby reduce any timing mismatches that could affect positioning accuracy. Notably, the network entity may supply a consistent designated Tx time to all entities from which it has requested timing information, ensuring timing alignment across devices.
[0043] In an implementation form of the second aspect, the one or more calculated timing values include a calculated TOF or, a calculated propagation delay, or a calculated RTOA.
[0044] This aspect ensures that the timing information received by the network entity can be based on various timing metrics, including TOF and RTOA, allowing it to compute accurate position data from different types of timing information.
[0045] In an implementation form of the second aspect, the timing information comprises: an UL RTOA, a DL RSTD, a RTT, or a Rx-Tx time difference.
[0046] This ensures that the network entity can work with a wide variety of timing metrics, covering both uplink and downlink scenarios, which enhances its ability to obtain accurate positioning.
[0047] In an implementation form of the second aspect, the first reference signal comprises a SRS or a PRS, and / or the second reference signal comprises a PRS or a SRS.
[0048] This feature supports the use of common reference signals in positioning, enabling the system to flexibly adapt to different signaling types and links.
[0049] In an implementation form of the second aspect, the network entity is a LMF.
[0050] This identifies the network entity as an LMF, which is responsible for managing positioning services in the system. By specifying the LMF, the system can coordinate the collection and processing of timing-related data across multiple devices, ensuring efficient and accurate location estimation. This enhances the applicability of the system for positioning and location-based services, ensuring precise signal measurements for location determination in a wireless network.
[0051] A third aspect of the disclosure provides a method performed by an entity for a wireless communication system, wherein the method comprises: receiving a first reference signal, determining timing information related to the first reference signal based on one or more calculated timing values associated with the first reference signal and a designated Tx time of the first reference signal, and providing the timing information related to the first reference signal to a network entity.
[0052] Implementation forms of the method of the third aspect may correspond to the implementation forms of the entity of the first aspect described above. The method of the third aspect and its implementation forms achieve the same advantages and effects as described above for the entity of the first aspect and its implementation forms.
[0053] A fourth aspect of the disclosure provides a method performed by a network entity, wherein the method comprises obtaining timing information related to a first reference signal from an entity, wherein the timing information is determined based on one or more calculated timing values associated with the first reference signal and a designated Tx time of the first reference signal.
[0054] Implementation forms of the method of the fourth aspect may correspond to the implementation forms of the network entity of the second aspect described above. The method of the fourth aspect and its implementation forms achieve the same advantages and effects as described above for the network entity of the second aspect and its implementation forms.
[0055] A fifth aspect of the disclosure provides a computer program or computer program product comprising a program code for carrying out, when implemented on a processor, the method according to the third aspect and any implementation forms of the third aspect, or the fourth aspect and any implementation forms of the fourth aspect.
[0056] It has to be noted that all devices, elements, units and means described in the present application could be implemented in software or hardware elements or any kind of combination thereof. All steps that are performed by the various entities described in the present application as well as the functionalities described to be performed by the various entities are intended to mean that the respective entity is adapted to or configured to perform the respective steps and functionalities. Even if, in the following description of specific embodiments, a specific functionality or step to be performed by external entities is not reflected in the description of a specific detailed element of that entity that performs that specific step or functionality, it should be clear for a skilled person that these methods and functionalities can be implemented in respective software or hardware elements or any kind of combination thereof.BRIEF DESCRIPTION OF THE DRAWINGS
[0057] The above-described aspects and implementation forms of the present disclosure will be explained in the following description of specific embodiments in relation to the enclosed drawings, in which:
[0058] FIG. 1 shows an entity according to an embodiment of the disclosure;
[0059] FIG. 2 shows a network entity according to an embodiment of the disclosure;
[0060] FIG. 3 shows a timing determination and reporting procedure according to an embodiment of the disclosure;
[0061] FIG. 4 shows a timing determination and reporting procedure according to an embodiment of the disclosure;
[0062] FIG. 5 shows a timing determination and reporting procedure according to an embodiment of the disclosure;
[0063] FIG. 6 shows signaling exchanges among entities according to an embodiment of the disclosure;
[0064] FIG. 7 shows signaling exchanges among entities according to an embodiment of the disclosure;
[0065] FIG. 8 shows signaling exchanges among entities according to an embodiment of the disclosure;
[0066] FIG. 9 shows signaling exchanges among entities according to an embodiment of the disclosure;
[0067] FIG. 10 shows signaling exchanges among entities according to an embodiment of the disclosure;
[0068] FIG. 11 shows signaling exchanges among entities according to an embodiment of the disclosure;
[0069] FIG. 12 shows a method according to an embodiment of the disclosure;
[0070] FIG. 13 shows a method according to an embodiment of the disclosure;
[0071] FIG. 14 shows a method according to an embodiment of the disclosure; and
[0072] FIG. 15 shows a method according to an embodiment of the disclosure.DETAILED DESCRIPTION
[0073] To facilitate a clear understanding of the present application, it is essential to first outline the foundational concepts of legacy positioning calculations commonly used in wireless communication systems. This context will help illustrate how the proposed enhancements can effectively address existing limitations.
[0074] Legacy positioning methodologies, such as TOA, TDOA, and related metrics, play a crucial role in estimating the position of UE in wireless networks. These calculations rely on the accurate measurement of signal propagation times between the UE and the network infrastructure, particularly gNB. Below, we define several key metrics utilized in these positioning calculations:
[0075] Time of Flight (TOF) :
[0076] TOF is the time taken for a signal to travel from the UE to the gNB or from the gNB to the UE. It is also referred to as propagation delay. If the TOF / propagation delay corresponds to a direct path between the UE and the gNB, i.e., of a LOS path between the UE and the gNB, the TOF can be used to determine the distance between the UE and the gNB.
[0077] Time of Arrival (TOA) :
[0078] TOA is the time when a signal transmitted by a UE or gNB arrives or is received at the gNB or UE, respectively the basic equation for TOA can be expressed as:
[0079] TOA = Tx time + Propagation delay. The Tx time corresponds to the time when a signal is transmitted.
[0080] Uplink Relative Time of Arrival (UL RTOA) :
[0081] UL RTOA indicates the time difference between the time of arrival of a signal at a TRP and a predetermined reference time. It is used for determining the position of the UE by leveraging signals sent from the UE and received by multiple TRPs. The calculation is given by:
[0082] UL RTOA = TOA -UL RTOA Reference time.
[0083] Downlink Reference Signal Time Difference (DL RSTD) :
[0084] DL RSTD refers to the time difference between the arrival times of two positioning reference signals sent by different TRPs and received by the UE. This metric helps to triangulate the UE's position based on signals transmitted from multiple TRPs. The calculation for DL RSTD can be expressed as: DL RSTD = TOA -Reference time, where the Reference time can correspond to the time of arrival of a reference signal sent by a reference TRP.
[0085] gNB Rx-Tx Time Difference:
[0086] This metric measures the difference in time between when a gNB receives a reference signal, i.e., SRS, sent by the UE and when it transmits a reference signal, i.e., PRS. This value is critical for understanding the timing relationships necessary for accurate positioning calculations involving round trip time. The calculation is defined as:
[0087] gNB Rx-Tx time diff. = Rx time of SRS -Tx time of PRS.
[0088] Accurate determination of this difference is essential for maintaining alignment in positioning measurements.
[0089] UE Rx-Tx Time Difference:
[0090] Similar to the gNB Rx-Tx time difference, this measures the timing difference between when the UE receives a reference signal, i.e., PRS, from the gNB and when it transmits a reference signal, i.e., SRS. The equation is given by: UE Rx-Tx time diff. = Rx time of PRS -Tx time of SRS.
[0091] This metric is also crucial for understanding the timing relationships and improving positioning accuracy.
[0092] Round Trip Time (RTT) :
[0093] RTT represents the total time it takes for a signal to travel from the UE to the gNB and back again. The RTT corresponds to twice the propagation delay between the UE and the gNB. This measurement is derived from the UE Rx-Tx time difference and the gNB Rx-Tx time difference. The formula for RTT is as follows:
[0094] RTT = UE Rx-Tx time diff. + gNB Rx-Tx time diff.
[0095] Based on the RTT, the system can derive the one-way propagation delay, which is vital for accurate positioning.
[0096] Despite their effectiveness under ideal conditions, these legacy methods encounter significant challenges in NLOS environments, where signal obstructions can lead to inaccurate measurements due to reflections, diffractions, and multipath effects.
[0097] Recognizing the limitations inherent in these legacy methods, the present application proposes a structured approach that enhances the accuracy and reliability of positioning systems considering also the calculation of the timing information of a reference signal, e.g., based on a trained model. In particular, it is beneficial if the timing information corresponds to the timing information of a direct path between the UE and gNB, even if there is no existing LOS path between the gNB and UE. Specifically, it focuses on the specification and alignment of Tx times for reference signals-SRS and PRS-among various network components.
[0098] The present disclosure describes an entity and a network entity in a wireless communication system, as well as various methods and embodiments related to determining and providing timing-related information for positioning. The embodiments leverage reference signals such as SRS and PRS to calculate timing values, such as TOF and RTOA, for accurate positioning.
[0099] Illustrative embodiments of the entity, the network entity, and corresponding methods, are described with reference to the figures. Although this description provides a detailed example of possible implementations, it should be noted that the details are intended to be exemplary and in no way limit the scope of the application.
[0100] Moreover, an embodiment or example may refer to other embodiments or examples. For example, any description including but not limited to terminology, element, process, explanation, and / or technical advantage mentioned in one embodiment / example is applicable to the other embodiments or examples.
[0101] FIG. 1 shows an entity 100 adapted for measuring reference signals according to an embodiment of the disclosure.
[0102] The entity 100 may comprise processing circuitry (not shown) configured to perform, conduct, or initiate the various operations of the entity 100 described herein. The processing circuitry may comprise hardware and software. The hardware may comprise analog circuitry digital circuitry, or both analog and digital circuitry. The digital circuitry may comprise components such as application-specific integrated circuits (ASICs) , field-programmable arrays (FPGAs) , digital signal processors (DSPs) , or multi-purpose processors. The entity 100 may further comprise memory circuitry, which stores one or more instruction (s) that can be executed by the processor or by the processing circuitry, in particular under the control of the software. For instance, the memory circuitry may comprise a non-transitory storage medium storing executable software code which, when executed by the processor or the processing circuitry, causes the various operations of the entity 100 to be performed. In one embodiment, the processing circuitry comprises one or more processors and a non-transitory memory connected to the one or more processors. The non-transitory memory may carry executable program code which, when executed by the one or more processors, causes entity 100 to perform, conduct or initiate the operations or methods described herein.
[0103] The entity 100 is configured to receive a first reference signal 101. Possibly, the first reference signal 101 is transmitted by one or more network nodes in the wireless communication system. For instance, the first reference signal 101 may include a SRS sent by a PRU or UE. In another instance, the first reference signal 101 may include a PRS sent by a gNB or TRP.
[0104] The entity 100 is configured to determine timing information 102 related to the first reference signal 101, based on one or more calculated timing values associated with the first reference signal 101 and a designated transmit time of the first reference signal 101.
[0105] The entity 100 is further configured to provide the timing information 102 related to the first reference signal 101 to a network entity 200.
[0106] This disclosure accordingly proposes an entity or device that determines timing-related information by calculating values associated with a reference signal and a designated Tx time. In particular, the designated Tx time may be received from the network entity 200, or determined by the entity locally. The approach ensures a common understanding on the determined timing-related information at different entities, enhancing the accuracy of the positioning. By providing this information to the network entity 200, such as an LMF, the system can optimize positioning performance, especially in NLOS scenarios.
[0107] Accordingly, FIG. 2 shows a network entity 200 according to an embodiment of the disclosure. The network entity 200 may comprise processing circuitry (not shown) configured to perform, conduct, or initiate the various operations of the network entity 200 described herein. The processing circuitry may comprise hardware and software. The hardware may comprise analog circuitry digital circuitry, or both analog and digital circuitry. The digital circuitry may comprise components such as ASICs, FPGAs, DSPs, or multi-purpose processors. The network entity 200 may further comprise memory circuitry, which stores one or more instruction (s) that can be executed by the processor or by the processing circuitry, in particular under the control of the software. For instance, the memory circuitry may comprise a non-transitory storage medium storing executable software code which, when executed by the processor or the processing circuitry, causes the various operations of the network entity 200 to be performed. In one embodiment, the processing circuitry comprises one or more processors and a non-transitory memory connected to the one or more processors. The non-transitory memory may carry executable program code which, when executed by the one or more processors, causes the network entity 200 to perform, conduct or initiate the operations or methods described herein.
[0108] The network entity 200 is configured to obtain timing information 102 related to a first reference signal 101 from an entity 100, wherein the timing information 102 is based on one or more calculated timing values associated with the first reference signal 101 and a designated Tx time of the first reference signal 101. Possibly, the entity 100 may be the entity 100 shown in FIG. 1.
[0109] This disclosure further proposes a device receiving timing information determined by the entity 100. With the reported timing information, the network entity 200 can perform positioning with the provided timing information. Possibly, the network entity 200 may be the LMF.
[0110] The following embodiments describe detailed scenarios where the entity 100 as shown in FIG. 1 interacts with a network entity 200 as shown in FIG. 2 in determining and reporting timing-related information for positioning purposes. In each case, the Tx time of the reference signal, such as a SRS or a PRS, used for determining the timing-related information may either be provided by the network entity 200, e.g., the LMF, or autonomously determined by the entity 100. In this embodiment and further embodiments of this disclosure, the Tx time of the reference signal, i.e., PRS or SRS, may be referred to as a designed Tx time of the reference signal.
[0111] FIG. 3 illustrates an embodiment where the entity 100, such as a gNB or TRP belonging to a gNB, performs channel measurements based on an SRS transmitted by a UE. These measurements are input into a model at the gNB, which has been trained to infer a calculated TOF of the direct path between the UE and the entity 100.
[0112] The Tx time of the SRS used in this process may either be provided by the network entity 200 (i.e., LMF) or determined autonomously by the gNB. The use of this Tx time, along with the calculated TOF and a UL RTOA reference time, enables the gNB to determine the UL RTOA. The UL RTOA is then sent to the network entity 200, which uses this information for UE positioning.
[0113] Optionally, rather than directly determining the TOF, the AI model at the gNB may be trained to infer an estimated or a calculated RTOA of the direct path between the UE and the gNB. The calculated RTOA is then processed to obtain the UL RTOA to be reported to the network entity. For example, based on the calculated RTOA, the gNB first derives an estimated TOF and then determines the UL RTOA, as illustrated by the dash block and dash lines of FIG. 3.
[0114] In an embodiment shown in FIG. 4, the entity 100 utilizes both SRS and PRS to calculate a time difference between the received and transmitted signals. The gNB performs channel measurements of the SRS transmitted by the UE and received by a TRP belonging to the gNB. These measurements are used as inputs to an AI model that calculates the TOF for the received SRS, i.e., the TOF of the direct path between the UE and the TRP.
[0115] The Tx times of both the SRS and PRS are essential for calculating the gNB Rx-Tx time difference based on a calculated TOF. These Tx times may either be provided by the network entity (LMF) or determined autonomously by the gNB. Once the Rx-Tx time difference is calculated, the gNB provides this information to the LMF for further positioning analysis.
[0116] In another variant of this embodiment, the measurements are performed by the UE instead of the gNB, i.e., the UE performs channel measurements of the PRS transmitted by a TRP belonging to the gNB, with the AI model at the UE inferring the TOF of the direct path between the UE and the TRP. The UE calculates the Rx-Tx time difference and sends it to the network entity. In this embodiment, the entity 100 is the UE.
[0117] Notably, for both variants, the AI model may be trained to infer a calculated RTOA of the direct path between the UE and the gNB, instead of to infer a calculated TOF. The calculated RTOA is then processed to obtain the gNB or UE Rx-Tx time difference to be reported to the network entity. For example, based on the calculated RTOA, the gNB or the UE first determines a calculated TOF, before determining the gNB or UE Rx-Tx time difference, as illustrated by the dash block and dash lines of FIG. 4.
[0118] In an embodiment shown in FIG. 5, the UE (the entity 100) performs channel measurements based on the PRS transmitted by a gNB or TRP belonging to a gNB. These channel measurements are taken as input to an AI model running on the UE, which has been trained to infer the calculated TOF of the direct path between the UE and the gNB / TRP. The model output can also be referred to as the calculated propagation delay along the direct path.
[0119] The UE is provided with the Tx time of the PRS, which is critical for determining the DL RSTD. The Tx time of the PRS can either be specified or indicated to the UE by the network entity, such as the LMF, ensuring that the timing used for calculations is aligned across the system.
[0120] Based on the calculated TOF, the designated Tx time of the PRS, and a reference time, the UE can calculate the DL RSTD. The reference time can correspond to the time of arrival of a PRS sent by another TRP, i.e., of reference TRP. This calculated DL RSTD is then reported back to the LMF, which uses this timing information for accurate positioning of the UE within the network.
[0121] In an alternative scenario within this embodiment, the calculated TOF may be derived from a RTOA, which is output by the AI model based on the PRS measurements, as illustrated by the dash block and dash lines of FIG. 5. The calculated RTOA can be processed further to obtain the DL RSTD to be reported to the network entity. For example, the calculated RTOA serves as an intermediate timing metric, allowing the TOF to be determined from the model’s output.
[0122] In the previous embodiments of this disclosure, the UE can be a PRU.
[0123] FIG. 6 shows signaling exchanges between entities according to an embodiment of this disclosure. In this embodiment, the network entity 200, e.g., the LMF, sends a request to the entity 100, e.g., the gNB, to calculate the UL RTOA based on the SRS transmitted by a PRU or UE. As part of the request, the LMF provides the gNB with the Tx time of the SRS that should be used for the calculation. In addition, the LMF can indicate the gNB to employ a calculated timing information of the SRS for the determination of the UL RTOA. The calculated timing information in this embodiment and further embodiments of this disclosure may be based on the model output of a model at the gNB.
[0124] The PRU or UE transmits the SRS 101, which is received by the gNB (or a TRP belonging to the gNB) . The SRS 101 can be received by a TRP belonging to the gNB, and the gNB / TRP makes channel measurements of the SRS 101. The measured data is input into an AI model. This model is trained to infer calculated timing information of the SRS, such as the TOF or the propagation delay of the direct path between the UE / PRU and the TRP. The calculated timing information may also correspond to a calculated RTOA of the SRS.
[0125] Using the calculated timing information and the provided Tx time of the SRS 101, the gNB determines the UL RTOA, i.e., the timing information 102 as shown in FIG. 1 and FIG. 2. This UL RTOA is then sent to the LMF, which uses the timing information 102 to calculate the position of the UE.
[0126] FIG. 7 shows signaling exchanges between entities according to an embodiment of this disclosure. In the embodiment, the network entity 200, e.g., the LMF, again sends a request to the entity 100, e.g., the gNB, to calculate the UL RTOA based on the SRS 101 transmitted by the PRU or UE. In addition, the LMF can indicate the gNB to employ a calculated timing information of the SRS for the determination of the UL RTOA. The SRS 101 can be received by a TRP belonging to the gNB, and the gNB / TRP performs channel measurements of the SRS 101. Similar to the embodiment discussed in FIG. 6, these measurements are used as input to an AI model at the gNB, which infers timing information associated with the received SRS 101 such as TOF or RTOA of the direct path between the PRU / UE and the TRP.
[0127] In this case, however, the gNB autonomously determines the Tx time of the SRS, e.g., to minimize quantization error during the calculation of the timing information 102, i.e., the UL RTOA. Using this determined Tx time and the calculated timing information, the gNB calculates the UL RTOA and reports both the UL RTOA and the determined Tx time of the SRS to the LMF. The LMF uses the received UL RTOA and Tx time to position the UE with improved precision.
[0128] FIG. 8 shows signaling exchanges between entities according to an embodiment of this disclosure. In this example, the network entity 200, e.g., the LMF, requests the entity 100, e.g., the gNB, to calculate the gNB Rx-Tx time difference, i.e., the timing information 102. The LMF sends the Tx time of both the SRS and the PRS to the gNB for use in this calculation. In addition, the LMF can indicate the gNB to employ a calculated timing information of the SRS for the determination of the gNB Rx-Tx time difference.
[0129] A PRU or UE transmits the SRS 101, which is received by the gNB (or a TRP belonging to the gNB) . The gNB performs channel measurements of the SRS 101, which are processed by an AI model to infer timing information, such as the TOF or propagation delay of the direct path between the UE / PRU and the TRP. Additionally, the gNB sends a PRS 103, which can be measured at the PRU / UE.
[0130] The gNB calculates the gNB Rx-Tx time difference based on the provided Tx times of the SRS 101 and PRS 103, as well as the inferred timing information. The timing information 102, i.e., the calculated gNB Rx-Tx time difference, is then sent to the LMF, which can use this information for accurate positioning of the UE.
[0131] In a variant of this embodiment, the LMF does not provide the Tx times of the SRS 101 and PRS 103, allowing the gNB to determine these values autonomously. When the gNB sends the calculated gNB Rx-Tx time difference to the LMF, it also includes the determined Tx times of the SRS 101 and PRS 103.
[0132] FIG. 9 shows signaling exchanges between entities according to an embodiment of this disclosure. The network entity 200, e.g., the LMF, sends a request to a PRU or UE (entity 100) to calculate the DL RSTD. The LMF also provides the PRU or UE with the Tx time of the PRS 101 that will be used in the calculation. In addition, the LMF can indicate the UE to employ a calculated timing information of the PRS for the determination of the DL RSTD.
[0133] The PRS 101 is transmitted by two TRPs, with TRP 1 acting as the reference TRP for the PRU or UE. The PRU or UE measures the PRS 101 transmitted by TRP 2 and uses these measurements as input to an AI model, which infers the TOF of the direct path between the TRP and the PRU / UE. Using the calculated TOF, the provided Tx time of PRS, and a reference time based on the PRS received from TRP 1, the PRU or UE determines the timing information 102, e.g., the DL RSTD.
[0134] The DL RSTD is sent to the LMF, which uses this information to accurately position the UE within the network.
[0135] FIG. 10 shows signaling exchanges between entities according to an embodiment of this disclosure. The network entity 200, e.g., the LMF, again requests a DL RSTD calculation from the PRU or UE (entity 100) , but this time, the UE determines the Tx time of the PRS itself, rather than relying on the LMF as discussed in the embodiment referring to FIG. 9.
[0136] Two TRPs, TRP 1 and TRP 2, transmit PRSs 101. TRP 1 acts as the reference for the DL RSTD calculation. The PRU or UE measures the PRS transmitted by TRP 2 and inputs the measurements into an AI model to infer the TOF of the direct path between the TRP and the PRU / UE. Using the inferred TOF, the Tx time of the PRS 101 (determined by the UE) , and a reference time derived from the PRS received from TRP 1, the UE calculates the timing information 102, i.e., the DL RSTD.
[0137] The UE then sends the calculated DL RSTD to the LMF, along with the Tx time of the PRS it used in the calculation. The LMF uses this data to accurately determine the position of the UE.
[0138] FIG. 11 shows signaling exchanges between entities according to an embodiment of this disclosure. In this embodiment, the network entity 200, e.g., the LMF, sends a request to the entity 100, e.g., the PRU or UE, to calculate the UE Rx-Tx time difference. The LMF also provides the PRU or UE with the Tx times of both the SRS and PRS.
[0139] The PRU or UE transmits the SRS, which can be received by the gNB (or a TRP belonging to the gNB) . Simultaneously, the gNB sends a PRS 101, which is measured by the UE. The channel measurements are input into an AI model at the UE, which calculates the TOF of the direct path between the TRP and the PRU or UE. Using the calculated TOF and the provided Tx times of the SRS and PRS, the UE determines the timing information 102, i.e., the UE Rx-Tx time difference.
[0140] The UE sends this calculated Rx-Tx time difference to the LMF, which can use the information for positioning purposes.
[0141] In an alternative version of this embodiment, the LMF does not provide the Tx times of the SRS and PRS. Instead, the UE determines these values independently and reports them along with the calculated Rx-Tx time difference to the LMF.
[0142] According to a further embodiment, the specified or indicated Tx time of the SRS in the above embodiments may be equal to T0+tSRS, where T0 is the nominal beginning time of subframe number 0 and tSRS= (10nf+nsf) ×10-3, with nf being the system frame number and nsf being the subframe number of the SRS.
[0143] According to a further embodiments, the specified or indicated Tx time of the PRS in the above embodiments may be equal to T0+tPRS, where T0 is the nominal beginning time of subframe number 0 and tPRS= (10nf+nsf) ×10-3, with nf being the system frame number and nsf being the subframe number of the PRS.
[0144] Another important aspect of this disclosure is that the LMF may request one or more gNBs to calculate the UL RTOA based on one or more SRSs sent by the PRU or UE. The one or more SRSs can be beamformed and transmitted at different times. The LMF can indicate a common Tx time of the one or more SRS that the one or more gNBs must use to calculate the UL RTOA.
[0145] Each gNB determines the UL RTOA using the calculated TOF, based on measurements of the one or more beamformed SRS sent by the PRU or UE, and the indicated common Tx time.
[0146] Another important aspect of this disclosure is that the Tx time of the reference signal may be indicated to the LMF only during the inference phase, i.e., the Tx time of the reference signal does not need to be indicated when the gNB or UE is training the model for inferring the timing value associated with the reference signal.
[0147] FIG. 12 presents an embodiment of the idea with one or more TRPs belonging to one gNB and where a UE transmits SRS which can be received at the one or more TRPs of the gNB. The UE could be a PRU. The gNB computes the calculated timing value of the direct path between the UE and the one or more TRPs, i.e., based on the channel measurements from the one or more TRPs and with a model trained to infer the calculated timing values. The model can consist of one model having as input the channel measurements of the one or more TRPs or the model can consist of one or more models, where each model has as model input the channel measurements of one TRP. The timing values can comprise a TOF or RTOA of the direct path between a TRP and the UE. The one or more timing values associated with the one or more TRPs are further processed by considering a Tx time of the SRS, in order to obtain the timing information of the one or more TRPs which can be sent to the LMF. The timing information can comprise a UL RTOA or DL RSTD.
[0148] FIG. 13 shows a method how the Tx time of SRS can be determined at the gNB. With one or more TRPs belonging to one gNB, a UE transmits SRS which can be received at the one or more TRPs of the gNB. The UE can be a PRU. Based on measurements of the SRS transmitted by the UE and received by the one or more TRPs of the gNB, the gNB determines which TRPs have a LOS to the UE. The gNB computes the calculated TOF of the direct path between the UE and the one or more TRPs, i.e., based on the channel measurements from the one or more TRPs and with a model trained to infer the calculated TOFs. For the TRPs which have been identified to have a LOS to the UE, the gNB measures the TOA of the SRS at the identified TRPs. With the calculated TOF and the measured TOAs of the TRPs with a LOS to the UE, the gNB can determine a Tx time of the SRS. For example, a Tx time of SRS can be determined by subtracting the calculated TOF from the measured TOA of one TRP. In this way, an average Tx time can be computed based on the calculated TOF and the measured TOAs of the TRPs with a LOS to the UE. The Tx time of SRS, along with the calculated TOFs associated with the one or more TRPs, can be used to determine the UL RTOA of the one or more TRPs to be sent to the LMF.
[0149] FIG. 14 shows a method 1400 according to an embodiment of the disclosure. In a particular embodiment, the method 1400 is performed by an entity 100 shown in FIG. 1 or 2, or one of FIG. 6 to FIG. 11. The method 1400 comprises a step 1401 of receiving a first reference signal 101, and a step 1402 of determining timing information 102 related to the first reference signal 101 based on one or more calculated timing values associated with the first reference signal 101 and a designated transmit time of the first reference signal 101.
[0150] The method 1400 further comprises a step 1403 of providing the timing information 102 related to the first reference signal 101 to a network entity 200. Finally, the entity 100 reports the timing information 102 to the network entity 200, such as the LMF or another network component. Possibly, the network entity 200 may be the network entity 200 shown in FIG. 1 or 2, or one of FIG. 6 to FIG. 11.
[0151] FIG. 15 shows a method 1500 according to an embodiment of the disclosure. In a particular embodiment, the method 1500 is performed by a network entity 200 shown in FIG. 1 or 2, or one of FIG. 6 to FIG. 11. The method 1500 comprises a step 1501 of obtaining timing information 102 related to a first reference signal 101 from an entity 100, wherein the timing information 102 is determined based on one or more calculated timing values associated with the first reference signal 101 and a designated transmit time of the first reference signal 101. Possibly, the entity 100 may be the entity 100 shown in FIG. 1 or 2, or one of FIG. 6 to FIG. 11.
[0152] To summarize, embodiments of this disclosure proposes the alignment of Tx time specifications for reference signals in various timing calculation, thereby supporting precise positioning across network entities and minimizing timing discrepancies in dynamic environments. The present disclosure focuses on gNBs, TRPs, PRUs, and UEs, aiming to achieve efficient alignment of the presumed Tx time of reference signals for accurate calculation of timing information. By aligning the presumed Tx time across network elements, the disclosure ensures common understanding of the Tx time of reference signals, enhancing the accuracy of calculated timing metrics for reference signals used in positioning and communication.
[0153] The present disclosure has been described in conjunction with various embodiments as examples as well as implementations. However, other variations can be understood and effected by those persons skilled in the art and practicing the claimed embodiments of the disclosure, from the studies of the drawings, this disclosure, and the independent claims. In the claims as well as in the description the word “comprising” does not exclude other elements or steps and the indefinite article “a” or “an” does not exclude a plurality. A single element or other unit may fulfill the functions of several entities or items recited in the claims. The mere fact that certain measures are recited in the mutually different dependent claims does not indicate that a combination of these measures cannot be used in an advantageous implementation.
[0154] Furthermore, any method according to embodiments of the disclosure may be implemented in a computer program, having code means, which when run by processing means causes the processing means to execute the steps of the method. The computer program is included in a computer-readable medium of a computer program product. The computer-readable medium may comprise essentially any memory, such as a ROM (Read-Only Memory) , a PROM (Programmable Read-Only Memory) , an EPROM (Erasable PROM) , a Flash memory, an EEPROM (Electrically Erasable PROM) , or a hard disk drive.
[0155] Moreover, it is realized by the skilled person that embodiments of the entity 100 or the network entity 200, comprise the necessary communication capabilities in the form of e.g., functions, means, units, elements, etc., for performing the solution. Examples of other such means, units, elements, and functions are processors, memory, buffers, control logic, encoders, decoders, rate matchers, de-rate matchers, mapping units, multipliers, decision units, selecting units, switches, interleavers, de-interleavers, modulators, demodulators, inputs, outputs, antennas, amplifiers, receiver units, transmitter units, DSPs, trellis-coded modulation (TCM) encoder, TCM decoder, power supply units, power feeders, communication interfaces, communication protocols, etc. which are suitably arranged together for performing the solution.
[0156] Especially, the processor (s) of the entity 100 or the network entity 200 may comprise, e.g., one or more instances of a CPU, a processing unit, a processing circuit, a processor, an ASIC, a microprocessor, or other processing logic that may interpret and execute instructions. The expression “processor” may thus represent a processing circuitry comprising a plurality of processing circuits, such as, e.g., any, some, or all of the ones mentioned above. The processing circuitry may further perform data processing functions for inputting, outputting, and processing of data comprising data buffering and device control functions, such as call processing control, user interface control, or the like.
Claims
1.An entity (100) for a wireless communication system, the entity (100) being configured to:receive a first reference signal (101) , determine timing information (102) related to the first reference signal (101) , based on one or more calculated timing values associated with the first reference signal (101) and a designated transmit time of the first reference signal (101) , andprovide the timing information (102) related to the first reference signal (101) to a network entity (200) .2.The entity (100) according to claim 1, configured to:receive a request from the network entity (200) , wherein the request indicates the entity (100) to provide the timing information (102) related to the first reference signal (101) .3.The entity (100) according to claim 1 or 2, configured to:receive the designated transmit time of the first reference signal (101) from the network entity (200) .4.The entity (100) according to claim 1 or 2, configured to:determine the designated transmit time of the first reference signal (101) , andindicate the designated transmit time of the first reference signal (101) to the network entity (200) .5.The entity (100) according to any preceding claims, wherein the one or more calculated timing values comprise: a calculated time of flight, TOF, a calculated propagation delay or a calculated relative time of arrival, RTOA.6.The entity (100) according to any preceding claims, configured to:generate the one or more calculated timing values using a model trained to infer timing information (102) related to the first reference signal (101) .7.The entity (100) according to claim 6, whereinthe input of the model is based on measurements of the first reference signal (101) .8.The entity (100) according to any preceding claims, wherein the timing information (102) comprises: an uplink relative time of arrival, UL RTOA, a downlink reference signal time difference, DL RSTD, a round trip time, RTT, or a receive-transmit time difference.9.The entity (100) according to any preceding claims, further configured totransmit a second reference signal (103) , and determine the timing information (102) based on a designated transmit time of the second reference signal (103) .10.The entity (100) according to claim 9, configured to:receive the designated transmit time of the second reference signal (103) from the network entity (200) .11.The entity (100) according to claim 9, configured to:determine the designated transmit time of the second reference signal (103) , andindicate the designated transmit time of the second reference signal (103) to the network entity (200) .12.The entity (100) according to any preceding claims, wherein the first reference signal (101) comprises a sounding reference signal, SRS, or a positioning reference signal, PRS, and / or the second reference signal (103) comprises a PRS or a SRS.13.The entity (100) according to any preceding claims, wherein the entity (100) is one of the following: a base station, a transmit receive point, a gNB, a position reference unit, or a user equipment.14.A network entity (200) in a wireless communication system, the network entity (200) being configured to:obtain timing information (102) related to a first reference signal (101) from an entity, wherein the timing information (102) is based on one or more calculated timing values associated with the first reference signal (101) and a designated transmit time of the first reference signal (101) .15.The network entity (200) according to claim 14, configured to:send a request to the entity (100) , wherein the request indicates the entity (100) to provide the timing information (102) related to the first reference signal (101) .16.The network entity (200) according to claim 14 or 15, configured to:provide the designated transmit time of the first reference signal (101) to the entity (100) , orreceive the designated transmit time of the first reference signal (101) from the entity (100) .17.The network entity (200) according to any preceding claims, wherein the one or more calculated timing values comprises:a calculated time of flight, TOF, a calculated propagation delay or a calculated relative time of arrival, RTOA.18.The network entity (200) according to any preceding claims, wherein the timing information (102) comprises: an uplink relative time of arrival, UL RTOA, a downlink reference signal time difference, DL RSTD, a round trip time, RTT, or a receive-transmit time difference.19.The network entity (200) according to any preceding claims, configured to:provide a designated transmit time of a second reference signal (103) to the entity (100) , orreceive the designated transmit time of the second reference signal (103) from the entity (100) .20.The network entity (200) according to any preceding claims, wherein the first reference signal (101) comprises a sounding reference signal, SRS, or a positioning reference signal, PRS, and / or the second reference signal (103) comprises a PRS or a SRS.21.The network entity (200) according to any preceding claims, wherein the network entity (200) is a location management function.22.A method (1400) performed by an entity (100) for a wireless communication system, the method (1400) comprising:receiving (1401) a first reference signal (101) , determining (1402) timing information (102) related to the first reference signal (101) based on one or more calculated timing values associated with the first reference signal (101) and a designated transmit time of the first reference signal (101) , andproviding (1403) the timing information (102) related to the first reference signal (101) to a network entity (200) .23.A method (1500) performed by a network entity (200) , the method comprising:obtaining (1501) timing information (102) related to a first reference signal (101) from an entity (100) , wherein the timing information (102) is determined based on one or more calculated timing values associated with the first reference signal (101) and a designated transmit time of the first reference signal (101) .24.A computer program product comprising computer readable code instructions which, when run in a computer will cause the computer to perform the method (1400, 1500) according to claim 22 or 23.