Wireless device propagation delay compensation in RRC idle or inactive

Abstract

A method, system, and apparatus for wireless device (WD) propagation delay compensation in a radio resource control (RRC) idle or inactive state are disclosed. According to one aspect, a method in a WD includes, when in an RRC connected state, obtaining a propagation delay compensation (PDC) configuration from a network node, the PDC configuration including a PDC value. The method further comprises, when in an RRC inactive or RRC idle state: obtaining a time value signaled from the network node; determining whether the PDC value is valid; and using the PDC value to compensate for the time value signaled from the network node when the PDC value is determined to be valid.

Description

Technical Field

[0001] The present disclosure relates to wireless communications, and in particular to wireless device (WD) propagation delay compensation in a radio resource control (RRC) idle or inactive state. Background Art

[0002] The Third Generation Partnership Project (3GPP) has developed and is currently developing standards for fourth-generation (4G) (also known as Long Term Evolution (LTE)) and fifth-generation (5G) (also known as New Radio (NR)) wireless communication systems. Among other features, such systems provide broadband communication between network nodes (such as base stations) and mobile wireless devices (WDs), as well as communication between network nodes and between WDs. 3GPP is also currently developing standards for sixth-generation (6G) wireless communication networks. introduce

[0003] In 3GPP Technical Release 8, the Evolved Packet System (EPS) was specified. EPS is based on the Long Term Evolution (LTE) radio network and the Evolved Packet Core (EPC). It was originally intended to provide voice and mobile broadband (MBB) services, but has been continuously evolved to broaden its functionality. Since 3GPP Release 13, Narrowband Internet of Things (NB-IoT) and LTE-M (LTE Machine Communication) have been part of the LTE specification and provide connectivity with massive machine-type communication (mMTC) services.

[0004] The first release of the 5G System (5GS) was specified in 3GPP Release 15. This is a new generation of radio access technology (RAT) intended to serve use cases such as enhanced mobile broadband (eMBB), ultra-reliable and low-latency communications (URLLC), and mobile machine-type communications (mMTC). 5GS includes the New Radio (NR) access layer interface and the 5G Core network (5GC).

[0005] During 3GPP Releases 16 and 17, 3GPP addressed support for different new use cases, including support for Time-Sensitive Networking (TSN) and Small Data Transfer (SDT). Now, in 3GPP Release 18, 3GPP has begun working on enabling 5G systems to deliver Time as a Service (TaaS) with high reliability and accuracy. TSN propagation delay compensation

[0006] To support TSN, 5GNR supports broadcast and unicast signaling of Coordinated Universal Time (UTC). To compensate for the propagation delay between the base station and the WD in the Radio Resource Control (RRC) connected state, i.e., the signal flight time (ToF), 5GNR supports propagation delay estimation and compensation. For example, the WD can add the estimated propagation delay to the UTC signaled by the base station to generate an accurate estimate of the actual UTC when receiving the UTC signaled by the base station. Figure 1 2 is a diagram illustrating the principle of propagation delay compensation applied to 5G NR System Information Block 9 UTC signaling.

[0007] 3GPP Release 17 specifies two different methods for supporting propagation delay compensation (PDC): compensation based on timing advance (TA) and round-trip time (RTT). The TA-based method is based on the principle that the TA assigned to a device performing uplink (UL) communications is approximately equal to twice the RTT. Therefore, TA / 2 is used as an estimate of the base station-to-WD propagation delay.

[0008] In the RTT method, the radio base station (hereinafter referred to as the network node) and the WD reception and transmission timing are measured on the UL and downlink (DL) to determine the time difference when the network node receives the transmission and the time difference when the WD receives the transmission (for example, WD RxTxTimeDiff and Network Node RxTxTimeDiff in the 3GPP standard (such as, for example, 3GPP Technical Standard (TS) 38.215v17.0.0)) to estimate the propagation delay as (WDRxTxTimeDiff+Network Node RxTxTimeDiff) / 2. These measurements are based on, for example, tracking reference signals in the DL and sounding reference signals in the UL. The detection timing of these signals supports higher accuracy than TA, which allows the RTT-based method to be performed with higher precision than the TA-based PDC method. Small data transfer

[0009] NR supports power-efficient transmission of small data packets from the RRC inactive state. WDs are pre-configured with a TA value by the network and are allowed to use the TA when performing UL transmissions from the RRC inactive state. WDs may need to validate the TA value before using it. One validation criterion is to check that the Reference Signal Received Power (RSRP) has not changed by more than a configured threshold since receiving the TA configuration. A large change in RSRP is intended to indicate that the WD has moved to such an extent that the pre-configured TA value is outdated. Taas (Time as a Service)

[0010] Taas (Time as a Service) is specified in 3GPP Release 18, which is studied by 3GPP SA2 in the study on 5G timing resilience and time-sensitive communication (TSC) and ultra-reliable and low-latency communication (URLLC) enhancements. It is expected to distribute UTC through unicast and broadcast signaling based on 5GNR capabilities. Several members of 3GPP SA2 have considered that 5GNR System Information Block 9 (SIB9) UTC signaling will enable support for Taas for devices in RRC inactive or idle state.

[0011] Allocating time to devices in RRC Inactive or Idle state via SIB9 does not allow the devices to perform propagation delay compensation (PDC) in a uniform and predictable manner, since 3GPP Release 17 PDC is only supported for WDs in RRC Connected state. This means that the Taas for devices in RRC Inactive or Idle state will not be as reliable as the Taas for devices in RRC Connected state, which can correct the received UTC signaled by the network through one of the 3GPP Release 17 PDC methods. Summary of the Invention

[0012] Some embodiments advantageously provide methods, network nodes, and wireless devices for wireless device (WD) propagation delay compensation in a radio resource control (RRC) idle or inactive state.

[0013] Some embodiments provide support for PDC for WDs in RRC inactive or RRC idle states to enable more accurate time allocation. Some embodiments provide methods for pre-configuring WDs in RRC connected states to support subsequent PDCs from RRC inactive or idle states. Some embodiments provide methods for verifying PDCs before using them in RRC inactive or idle states.

[0014] One advantage of some embodiments is that better network control over the accuracy of allocation time of WDs is achieved in RRC inactive or idle states.

[0015] According to one aspect, a method in a wireless device (WD) configured to communicate with a network node is provided. The method includes, while in a radio resource control (RRC) connected state, obtaining a propagation delay compensation (PDC) configuration from the network node, the PDC configuration including a PDC value. The method also includes, while in an RRC inactive or RRC idle state: obtaining a time value signaled from the network node; determining whether the PDC value is valid; and, if the PDC value is determined to be valid, compensating the time value signaled from the network node using the PDC value.

[0016] According to this aspect, in some embodiments, the method includes, when the PDC value is determined to be invalid, entering an RRC connected state and obtaining a subsequent PDC configuration. In some embodiments, the method includes, when the PDC value is determined to be invalid, adjusting the PDC value while in an RRC idle state or an RRC inactive state. In some embodiments, adjusting the PDC value is based at least in part on: a change in the WD's position relative to the network node since the time the PDC value was obtained; a change in the time of receipt of a downlink signal; or a change in a time offset from a local prime time. In some embodiments, the time value received from the network node is Coordinated Universal Time (UTC) or Global Positioning System (GPS) time. In some embodiments, the method includes performing PDC based at least in part on the PDC value until the WD changes cells. In some embodiments, determining whether the PDC value is valid is based at least in part on a detected signal measurement change that is less than a first threshold. In some embodiments, the signal measurement is one of reference signal received power, reference signal received quality, signal-to-interference-plus-noise ratio, and signal-to-noise ratio. In some embodiments, the detected signal measurement change includes a change between a first sample of a signal measurement performed at a first time and a second sample of a signal measurement performed at a second time after the first time, the first time being the time the PDC value was obtained. In some embodiments, a PDC value is determined to be invalid when the absolute value of a detected signal measurement change exceeds a second threshold. In some embodiments, determining whether the PDC value is valid includes comparing a time difference between receiving the first signal and receiving the second signal with a third threshold. In some embodiments, the first signal is one of a synchronization signal, a physical broadcast channel, a tracking reference signal, and a positioning reference signal from the cell where the WD is residing. In some embodiments, the second signal is one of a synchronization signal, a physical broadcast channel, a tracking reference signal, and a positioning reference signal from a neighboring cell to the cell where the WD is residing. In some embodiments, determining whether the PDC value is valid includes determining a change in signal measurements over a series of times. In some embodiments, determining whether the PDC value is valid includes comparing a change in at least one of the WD's position and orientation with a fourth threshold. In some embodiments, determining whether the PDC value is valid includes comparing a PDC-compensated version of a time value signaled from a network node with a local primary time. In some embodiments, the local primary time is a global navigation satellite system time. In some embodiments, the PDC configuration includes at least one of a PDC method, permission to update the PDC value, a PDC verification method, and a time interval during which the WD is to apply the PDC configuration. In some embodiments, the PDC method is one of a timing advance-based method and a round-trip time-based method. In some embodiments, the round trip time based method comprises transmitting a sounding reference signal, SRS, in an RRC inactive state, and the WD is configured to receive the time difference value based on a measurement of the SRS by the network node.

[0017] According to another aspect, a wireless device (WD) configured to communicate with a network node is provided. The WD is configured to: when in a radio resource control (RRC) connected state, obtain a propagation delay compensation (PDC) configuration from the network node, the PDC configuration including a PDC value; and when in an RRC inactive or RRC idle state: obtain a time value signaled from the network node; determine whether the PDC value is valid; and when the PDC value is determined to be valid, use the PDC value to compensate for the time value signaled from the network node.

[0018] According to this aspect, in some embodiments, when a PDC value is determined to be invalid, an RRC connected state is entered and the next PDC configuration is acquired. In some embodiments, when the PDC value is determined to be invalid, the PDC value is adjusted while in an RRC idle state or an RRC inactive state. In some embodiments, the PDC value is adjusted based at least in part on: a change in the WD's position relative to the network node since the time the PDC value was obtained; a change in the time of receipt of a downlink signal; or a change in a time offset from a local prime time or a global navigation satellite system time. In some embodiments, the time value received from the network node is Coordinated Universal Time (UTC) or Global Positioning System (GPS) time. In some embodiments, the WD is configured to perform PDC based on the PDC value until the WD changes cells. In some embodiments, determining whether the PDC value is valid is based at least in part on a detected signal measurement change that is less than a first threshold. In some embodiments, the signal measurement is one of reference signal received power, reference signal received quality, signal to interference plus noise ratio, and signal to noise ratio. In some embodiments, the detected signal measurement change comprises a change between a first sample of a signal measurement performed at a first time and a second sample of a signal measurement performed at a second time after the first time, the first time being the time the PDC value was obtained. In some embodiments, a PDC value is determined to be invalid when the absolute value of a detected signal measurement change exceeds a second threshold. In some embodiments, determining whether the PDC value is valid includes comparing a time difference between receiving the first signal and receiving the second signal with a third threshold. In some embodiments, the first signal is one of a synchronization signal, a physical broadcast channel, a tracking reference signal, and a positioning reference signal from the cell where the WD is residing. In some embodiments, the second signal is one of a synchronization signal, a physical broadcast channel, a tracking reference signal, and a positioning reference signal from a neighboring cell to the cell where the WD is residing. In some embodiments, determining whether the PDC value is valid includes determining a change in signal measurements over a series of times. In some embodiments, determining whether the PDC value is valid includes comparing a change in at least one of the WD's position and orientation with a fourth threshold. In some embodiments, determining whether the PDC value is valid includes comparing a PDC-compensated version of a time value signaled by the network node with a local primary time. In some embodiments, the local primary time is a global navigation satellite system time. In some embodiments, the PDC configuration includes at least one of a PDC method, permission to update the PDC value, a PDC verification method, and a time interval during which the WD is to apply the PDC configuration. In some embodiments, the PDC method is one of a timing advance-based method and a round-trip time-based method. In some embodiments, the round trip time based method comprises transmitting a sounding reference signal, SRS, in an RRC inactive state, and the WD is configured to receive the time difference value based on a measurement of the SRS by the network node.

[0019] According to another aspect, a method in a network node configured to communicate with a wireless device (WD) is provided. The method includes providing a propagation delay compensation (PDC) configuration to the WD when the WD is in a radio resource control (RRC) connected state. The method also includes signaling a time value to the WD when the WD is in an RRC inactive state or an RRC idle state. The PDC configuration includes a PDC value to be used by the WD in the RRC inactive state or the RRC idle state to compensate for the time value when the WD determines that the PDC value is valid.

[0020] According to this aspect, in some embodiments, the time value transmitted by the network node is Coordinated Universal Time (UTC) or Global Positioning System (GPS) time. In some embodiments, the PDC configuration includes at least one of a PDC method, a permission to update the PDC value, a PDC verification method, and a time interval in which the WD is to apply the PDC configuration. In some embodiments, the PDC method is one of a timing advance-based method and a round-trip time-based method. In some embodiments, the method includes providing a subsequent PDC configuration when the WD determines that the PDC value is invalid. In some embodiments, the method includes signaling a first threshold to the WD to compare with a signal measurement or a change in signal measurement to determine whether the PDC value is valid. In some embodiments, the method includes configuring the WD to transmit a sounding reference signal (SRS) during an RRC inactive state. In some embodiments, the method includes configuring the WD to autonomously adjust the PDC value based at least in part on a time offset or a downlink signal reception time difference. In some embodiments, the method includes configuring the WD to stop executing PDC when the WD is changing cells.

[0021] According to yet another aspect, a network node configured to communicate with a wireless device (WD) is provided. The network node is configured to: provide a propagation delay compensation (PDC) configuration to the WD when the WD is in a radio resource control (RRC) connected state; and signal a time value to the WD when the WD is in an RRC inactive state or an RRC idle state. The PDC configuration includes a PDC value to be used by the WD in the RRC inactive state or the RRC idle state to compensate for the time value when the WD determines that the PDC value is valid.

[0022] According to this aspect, in some embodiments, the time value transmitted by the network node is Coordinated Universal Time (UTC) or Global Positioning System (GPS) time. In some embodiments, the PDC configuration includes at least one of a PDC method, permission to update the PDC value, a PDC verification method, and a time interval during which the WD is to apply the PDC configuration. In some embodiments, the PDC method is one of a timing advance-based method and a round-trip time-based method. In some embodiments, the network node is further configured to provide a subsequent PDC configuration when the WD determines that the PDC value is invalid. In some embodiments, the network node is configured to signal a first threshold to the WD for comparison with a signal measurement or a change in signal measurement to determine whether the PDC value is valid. In some embodiments, the network node is configured to configure the WD to transmit a sounding reference signal (SRS) during an RRC inactive state. In some embodiments, the network node is configured to configure the WD to autonomously adjust the PDC value based at least in part on a time offset or a downlink signal reception time difference. In some embodiments, the network node is configured to configure the WD to stop executing PDC when the WD is changing cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] A more complete understanding of the present embodiments and its attendant advantages and features will be more readily appreciated by reference to the following detailed description when considered in conjunction with the accompanying drawings, in which: Figure 1 is a timing diagram illustrating timing between a network node and a wireless device; Figure 2 is a schematic diagram illustrating an example network architecture of a communication system connected to a host computer via an intermediate network according to the principles of the present disclosure; Figure 3 is a block diagram of a host computer communicating with a wireless device via a network node over an at least partially wireless connection according to some embodiments of the present disclosure; Figure 4 is a flow chart illustrating an example method for executing a client application at a wireless device implemented in a communication system including a host computer, a network node, and a wireless device according to some embodiments of the present disclosure; Figure 5 is a flow chart illustrating an example method for receiving user data at a wireless device implemented in a communication system including a host computer, a network node, and a wireless device according to some embodiments of the present disclosure; Figure 6 is a flow chart illustrating an example method implemented in a communication system including a host computer, a network node, and a wireless device for receiving user data at a host computer from a wireless device according to some embodiments of the present disclosure; Figure 7is a flow chart illustrating an example method for receiving user data at a host computer implemented in a communication system including a host computer, a network node, and a wireless device according to some embodiments of the present disclosure; Figure 8 is a flow chart of an example process in a network node for wireless device (WD) propagation delay compensation in a radio resource control (RRC) idle or inactive state; Figure 9 is a flow chart of an example process in a wireless device for propagation delay compensation for a wireless device (WD) in a radio resource control (RRC) idle or inactive state; Figure 10 is a flow chart of an example process in a wireless device for wireless device (WD) propagation delay compensation in a radio resource control (RRC) idle or inactive state; and Figure 11 is a flow chart of an example process in a network node for wireless device (WD) propagation delay compensation in a radio resource control (RRC) idle or inactive state; Figure 12 is a flow chart of another example process in a wireless device for wireless device (WD) propagation delay compensation in a radio resource control (RRC) idle or inactive state. DETAILED DESCRIPTION

[0024] Before describing the exemplary embodiments in detail, it is noted that the embodiments reside primarily in a combination of apparatus components and processing steps related to propagation delay compensation for a wireless device (WD) in a radio resource control (RRC) idle or inactive state. Accordingly, in the accompanying drawings, components have been represented by conventional symbols where appropriate, and only those specific details relevant to understanding the embodiments are shown so as not to obscure the disclosure with details that will be apparent to one of ordinary skill in the art having the benefit of the description herein. Like reference numerals refer to like elements throughout the description.

[0025] As used herein, relational terms such as "first" and "second", "top" and "bottom", etc., may be used only to distinguish one entity or element from another entity or element, without necessarily requiring or implying any physical or logical relationship or order between such entities or elements. The terms used herein are for the purpose of describing specific embodiments only and are not intended to be limitations of the concepts described herein. Unless the context clearly indicates otherwise, as used herein, the singular forms "a", "an", and "said" are intended to include the plural forms as well. It will be further understood that when used herein, the terms "comprises", "comprising", "includes", and / or "including" specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0026] In the embodiments described herein, connection terms "in communication with..." and the like may be used to indicate that electrical or data communication may be achieved through, for example, physical contact, induction, electromagnetic radiation, radio signaling, infrared signaling, or optical signaling. Those skilled in the art will appreciate that the various components may interoperate and that modifications and variations are possible to achieve electrical and data communication.

[0027] In some embodiments described herein, the terms "coupled," "connected," and the like may be used herein to indicate connection (though not necessarily direct) and may include wired and / or wireless connections.

[0028] The term "network node" as used herein may be any type of network node included in a radio network, and the network node may further include any of the following: a base station (BS), a radio base station, a base transceiver station (BTS), a base station controller (BSC), a radio network controller (RNC), a gNodeB (gNB), an evolved NodeB (eNB or eNodeB), a NodeB, a multi-standard radio (MSR) radio node such as an MSRBS, a multi-cell / multicast coordination entity (MCE), an integrated access and backhaul (IAB) node, a relay node, a donor node that controls a relay, a radio access point (AP), a transmission point, a transmission node, a remote radio unit (RRU), a remote radio head (RRH), a core network node (e.g., a mobility management entity (MME), a self-organizing network (SON) node, a coordination node, a positioning node, an MDT node, etc.), an external node (e.g., a third-party node, a node outside the current network), a node in a distributed antenna system (DAS), a spectrum access system (SAS) node, an element management system (EMS), etc. The network node may also include test equipment. The term "radio node" as used herein may also be used to denote a wireless device (WD) such as a wireless device (WD) or a radio network node.

[0029] In some embodiments, the non-limiting terms wireless device (WD) or user equipment (UE) are used interchangeably. A WD herein may be any type of wireless device, such as a wireless device (WD), capable of communicating with a network node or another WD via radio signals. A WD may also be a radio communication device, a target device, a device-to-device (D2D) WD, a machine-type WD, or a WD capable of machine-to-machine communication (M2M), a low-cost and / or low-complexity WD, a sensor equipped with a WD, a tablet computer, a mobile terminal, a smartphone, a laptop embedded device (LEE), a laptop mounted device (LME), a USB dongle, a customer premises equipment (CPE), an Internet of Things (IoT) device, or a narrowband IoT (NB-IOT) device, etc.

[0030] Furthermore, in some embodiments, the general term "radio network node" is used. It can be any kind of radio network node, which can include any of the following: base station, radio base station, base transceiver station, base station controller, network controller, RNC, evolved Node B (eNB), Node B, gNB, multi-cell / multicast coordination entity (MCE), IAB node, relay node, access point, radio access point, remote radio unit (RRU), remote radio head (RRH).

[0031] Note that while terminology from one particular wireless system, such as 3GPP LTE and / or New Radio (NR), may be used in the present disclosure, this should not be considered to limit the scope of the disclosure to only the aforementioned systems. Other wireless systems, including but not limited to Wideband Code Division Multiple Access (WCDMA), Worldwide Interoperability for Microwave Access (WiMax), Ultra Mobile Broadband (UMB), and Global System for Mobile Communications (GSM), may also benefit from utilizing the concepts encompassed within the present disclosure.

[0032] It is further noted that the functionality described herein as being performed by a wireless device or network node may be distributed across multiple wireless devices and / or network nodes. In other words, it is contemplated that the functionality of the network nodes and wireless devices described herein are not limited to being performed by a single physical device and may in fact be distributed among several physical devices.

[0033] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. It will be further understood that the terms used herein may be interpreted as having a meaning consistent with their meaning in the context of this specification and the relevant art, and that the terms used herein will not be interpreted in an idealized or overly formal sense unless explicitly defined as such herein.

[0034] Some embodiments provide wireless device (WD) propagation delay compensation in a radio resource control (RRC) idle or inactive state.

[0035] Turning now to the drawings, wherein like elements are referred to by like reference numerals, Figure 2, a schematic diagram of a communication system 10 (such as a 3GPP-type cellular network that can support standards such as LTE and / or NR (5G)) according to an embodiment is shown, the communication system including an access network 12 (such as a radio access network) and a core network 14. Access network 12 includes a plurality of network nodes 16a, 16b, 16c (collectively referred to as network nodes 16), such as NBs, eNBs, gNBs, or other types of wireless access points, each of which defines a corresponding coverage area 18a, 18b, 18c (collectively referred to as coverage area 18). Each network node 16a, 16b, 16c is connectable to core network 14 via a wired or wireless connection 20. A first wireless device (WD) 22a located in coverage area 18a is configured to wirelessly connect to or be paged by the corresponding network node 16a. A second WD 22b in coverage area 18b is wirelessly connectable to the corresponding network node 16b. Although multiple WDs 22a, 22b (collectively referred to as wireless devices 22) are shown in this example, the disclosed embodiments are equally applicable to situations where only a single WD is in the coverage area or where a single WD is connected to a corresponding network node 16. Note that although only two WDs 22 and three network nodes 16 are shown for convenience, the communication system may include many more WDs 22 and network nodes 16.

[0036] It is also contemplated that the WD 22 may be in simultaneous communication with more than one network node 16 and more than one type of network node 16, and / or may be configured to communicate solely with more than one network node 16 and more than one type of network node 16. For example, the WD 22 may have dual connectivity with a network node 16 that supports LTE and the same or different network node 16 that supports NR. As an example, the WD 22 may communicate with an eNB for LTE / E-UTRAN and a gNB for NR / NG-RAN.

[0037] The communication system 10 itself can be connected to a host computer 24, which can be implemented through the hardware and / or software of a stand-alone server, a cloud-enabled server, a distributed server, or as a processing resource in a server farm. The host computer 24 can be owned or controlled by a service provider, or can be operated by or on behalf of a service provider. The connections 26, 28 between the communication system 10 and the host computer 24 can extend directly from the core network 14 to the host computer 24, or can extend via an optional intermediate network 30. The intermediate network 30 can be a combination of one or more networks, including a public, private, or managed network. The intermediate network 30, if any, can be a backbone network or the Internet. In some embodiments, the intermediate network 30 may include two or more subnetworks (not shown).

[0038] Figure 2The communication system as a whole enables connectivity between one of the connected WDs 22a, 22b and the host computer 24. The connectivity can be described as an over-the-top (OTT) connection. The host computer 24 and the connected WDs 22a, 22b are configured to communicate data and / or signaling via the OTT connection using the access network 12, the core network 14, any intermediate networks 30, and any other possible infrastructure (not shown) as an intermediary. The OTT connection can be transparent in the sense that at least some of the participating communication devices through which the OTT connection passes are unaware of the routing of uplink and downlink communications. For example, the network node 16 may not or need not be informed of the past routing of incoming downlink communications with data originating from the host computer 24 to be forwarded (e.g., handed over) to the connected WD 22a. Similarly, the network node 16 does not need to know the future routing of outgoing uplink communications originating from the WD 22a toward the host computer 24.

[0039] The network node 16 is configured to include a PDC unit 32, which can be configured to determine a PDC value based at least in part on sounding reference signal measurements. In some embodiments, the PDC unit 32 can be configured to provide the PDC configuration to the WD 22. The wireless device 22 is configured to include a verification unit 34, which can be configured to verify the PDC value. In some embodiments, the verification is based at least in part on one of a comparison of a difference in sounding reference signal (SRS) measurements with a first threshold and a comparison of a difference in timing advance with a second threshold.

[0040] Now refer to Figure 3hereinafter is a description of an example implementation according to an embodiment of the WD 22, the network node 16 and the host computer 24 described in the above paragraphs. In the communication system 10, the host computer 24 includes hardware (HW) 38, which includes a communication interface 40, which is configured to establish and maintain a wired or wireless connection with the interface of different communication devices of the communication system 10. The host computer 24 also includes a processing circuit 42, which may have storage and / or processing capabilities. The processing circuit 42 may include a processor 44 and a memory 46. In particular, as an addition or alternative to a processor (such as a central processing unit) and a memory, the processing circuit 42 may include an integrated circuit for processing and / or control, such as one or more processors and / or processor cores and / or FPGAs (field programmable gate arrays) and / or ASICs (application-specific integrated circuits) suitable for executing instructions. The processor 44 may be configured to access (e.g., write to and / or read from) a memory 46, which may include any kind of volatile and / or non-volatile memory, such as a cache memory and / or buffer memory and / or RAM (Random Access Memory) and / or ROM (Read Only Memory) and / or optical memory and / or EPROM (Erasable Programmable Read Only Memory).

[0041] Processing circuitry 42 may be configured to control any of the methods and / or processes described herein and / or cause such methods and / or processes to be performed, for example, by host computer 24. Processor 44 corresponds to one or more processors 44 configured to perform the functions of host computer 24 described herein. Host computer 24 includes memory 46 configured to store data, programming software code, and / or other information described herein. In some embodiments, software 48 and / or host application 50 may include instructions that, when executed by processor 44 and / or processing circuitry 42, cause processor 44 and / or processing circuitry 42 to perform the processes described herein for host computer 24. The instructions may be software associated with host computer 24.

[0042] The software 48 may be executable by the processing circuitry 42. The software 48 includes a host application 50. The host application 50 may be operable to provide services to a remote user, such as a WD 22 connected via an OTT connection 52 terminated between the WD 22 and the host computer 24. In providing services to the remote user, the host application 50 may provide user data, which is transmitted using the OTT connection 52. "User data" may be data and information described herein as implementing the functionality described. In one embodiment, the host computer 24 may be configured to provide control and functionality to a service provider and may be operated by or on behalf of the service provider. The processing circuitry 42 of the host computer 24 may enable the host computer 24 to observe, monitor, control, transmit to and / or receive from the network node 16 and / or wireless device 22.

[0043] Communication system 10 also includes a network node 16, which is provided within communication system 10 and includes hardware 58 that enables it to communicate with host computer 24 and with WD 22. Hardware 58 may include a communication interface 60 for establishing and maintaining wired or wireless connections to interfaces with various communication devices of communication system 10, and a radio interface 62 for establishing and maintaining at least a wireless connection 64 with WD 22 located within coverage area 18 served by network node 16. Radio interface 62 may be formed as or include, for example, one or more RF transmitters, one or more RF receivers, and / or one or more RF transceivers. Communication interface 60 may be configured to facilitate a connection 66 to host computer 24. Connection 66 may be direct, or it may pass through core network 14 of communication system 10 and / or one or more intermediate networks 30 external to communication system 10.

[0044] In the illustrated embodiment, the hardware 58 of the network node 16 also includes processing circuitry 68. The processing circuitry 68 may include a processor 70 and a memory 72. In particular, in addition to or in lieu of a processor (such as a central processing unit) and a memory, the processing circuitry 68 may include an integrated circuit for processing and / or control, such as one or more processors and / or processor cores and / or an FPGA (field programmable gate array) and / or an ASIC (application-specific integrated circuit) suitable for executing instructions. The processor 70 may be configured to access (e.g., write to and / or read from) the memory 72, which may include any type of volatile and / or non-volatile memory, such as a cache memory and / or buffer memory and / or RAM (random access memory) and / or ROM (read-only memory) and / or optical memory and / or EPROM (erasable programmable read-only memory).

[0045] Thus, network node 16 further includes software 74, which is stored internally, for example, in memory 72 or in external memory (e.g., a database, storage array, network storage device, etc.) accessible to network node 16 via an external connection. Software 74 may be executable by processing circuitry 68. Processing circuitry 68 may be configured to control any of the methods and / or processes described herein and / or cause such methods and / or processes to be performed, for example, by network node 16. Processor 70 corresponds to one or more processors 70 configured to perform the functions of network node 16 as described herein. Memory 72 is configured to store data, programming software code, and / or other information as described herein. In some embodiments, software 74 may include instructions that, when executed by processor 70 and / or processing circuitry 68, cause processor 70 and / or processing circuitry 68 to perform the processes described herein for network node 16. For example, processing circuitry 68 of network node 16 may include PDC unit 32 configured to determine a PDC value based at least in part on sounding reference signal measurements.

[0046] The communication system 10 also includes the already mentioned WD 22. The WD 22 may have hardware 80, which may include a radio interface 82 configured to establish and maintain a wireless connection 64 with a network node 16 serving the coverage area 18 in which the WD 22 is currently located. The radio interface 82 may be formed as or may include, for example, one or more RF transmitters, one or more RF receivers, and / or one or more RF transceivers.

[0047] The hardware 80 of the WD 22 also includes processing circuitry 84. The processing circuitry 84 may include a processor 86 and a memory 88. In particular, in addition to or in lieu of a processor (such as a central processing unit) and a memory, the processing circuitry 84 may include an integrated circuit for processing and / or control, such as one or more processors and / or processor cores and / or an FPGA (field programmable gate array) and / or an ASIC (application-specific integrated circuit) suitable for executing instructions. The processor 86 may be configured to access (e.g., write to and / or read from) the memory 88, which may include any type of volatile and / or non-volatile memory, such as a cache memory and / or buffer memory and / or RAM (random access memory) and / or ROM (read-only memory) and / or optical memory and / or EPROM (erasable programmable read-only memory).

[0048] Therefore, WD22 may also include software 90, which is stored in, for example, memory 88 at WD22 or in an external memory accessible by WD22 (e.g., a database, storage array, network storage device, etc.). The software 90 may be executable by the processing circuit 84. The software 90 may include a client application 92. The client application 92 may be operable to provide services to human or non-human users via WD 22 with the support of the host computer 24. In the host computer 24, the executing host application 50 may communicate with the executing client application 92 via the OTT connection 52 terminated at WD22 and the host computer 24. When providing services to users, the client application 92 may receive request data from the host application 50 and provide user data in response to the request data. The OTT connection 52 may transmit the request data and the user data. The client application 92 may interact with the user to generate the user data it provides.

[0049] The processing circuitry 84 may be configured to control any of the methods and / or processes described herein and / or cause such methods and / or processes to be performed, for example, by the WD 22. The processor 86 corresponds to one or more processors 86 configured to perform the functions of the WD 22 described herein. The WD 22 includes a memory 88 configured to store data, programming software code, and / or other information described herein. In some embodiments, the software 90 and / or client application 92 may include instructions that, when executed by the processor 86 and / or the processing circuitry 84, cause the processor 86 and / or the processing circuitry 84 to perform the processes described herein for the WD 22. For example, the processing circuitry 84 of the wireless device 22 may include a verification unit 34 configured to verify the PDC value based at least in part on a comparison of a difference in a sounding reference signal (SRS) measurement with a first threshold and a comparison of a difference in a timing advance with a second threshold.

[0050] In some embodiments, the internal workings of network node 16, WD 22, and host computer 24 may be as follows: Figure 3 As shown in , and independently, the surrounding network topology can be Figure 2 network topology.

[0051] Figure 3In FIG, OTT connection 52 has been abstractly drawn to illustrate communication between host computer 24 and wireless device 22 via network node 16, without explicitly mentioning any intermediary devices and the exact routing of messages through these devices. The network infrastructure can determine the routing, which it can configure to be hidden from WD 22 or the service provider operating host computer 24, or both. While OTT connection 52 is active, the network infrastructure can further make decisions by which it dynamically changes the routing (e.g., based on load balancing considerations or reconfiguration of the network).

[0052] The wireless connection 64 between the WD 22 and the network node 16 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments utilize the OTT connection 52 to improve the performance of the OTT service provided to the WD 22, in which the wireless connection 64 may form the final leg. More specifically, the teachings of some of these embodiments may improve data rates, latency, and / or power consumption, thereby providing benefits such as reduced user wait time, relaxed file size restrictions, better responsiveness, extended battery life, and the like.

[0053] In some embodiments, a measurement process may be provided to facilitate monitoring of data rates, latency, and other factors that may be improved upon by one or more embodiments. Optional network functionality may also be provided for reconfiguring the OTT connection 52 between the host computer 24 and the WD 22 in response to changes in measurement results. The measurement process and / or network functionality for reconfiguring the OTT connection 52 may be implemented by the software 48 of the host computer 24, the software 90 of the WD 22, or both. In embodiments, sensors (not shown) may be deployed in or associated with the communication device through which the OTT connection 52 passes; the sensors may participate in the measurement process by providing values of the monitored quantities exemplified above or other physical quantities from which the software 48, 90 can calculate or estimate the monitored quantities. Reconfiguration of the OTT connection 52 may include message formats, retransmission settings, preferred routing, and the like; reconfiguration need not affect the network node 16 and may be unknown or imperceptible to the network node 16. Some such processes and functionality may be known and implemented in the art. In some embodiments, the measurements may involve proprietary WD signaling that facilitates host computer 24 measurements of throughput, propagation time, latency, etc. In some embodiments, the measurements may be achieved as the software 48, 90 causes messages, particularly null or 'dummy' messages, to be transmitted using the OTT connection 52 while monitoring propagation time, errors, etc.

[0054] Thus, in some embodiments, host computer 24 includes processing circuitry 42 configured to provide user data and communication interface 40 configured to forward the user data to a cellular network for transmission to WD 22. In some embodiments, cellular network also includes a network node 16 having a radio interface 62. In some embodiments, network node 16 is configured and / or processing circuitry 68 of network node 16 is configured to perform the functions and / or methods described herein for preparing / initiating / maintaining / supporting / ending transmissions to WD 22 and / or preparing / terminating / maintaining / supporting / ending receipt of transmissions from WD 22.

[0055] In some embodiments, host computer 24 includes processing circuitry 42 and communication interface 40 configured to receive user data from transmissions from WD 22 to network node 16. In some embodiments, WD 22 is configured to perform the functions and / or methods described herein for preparing / initiating / maintaining / supporting / ending transmissions to network node 16 and / or preparing / terminating / maintaining / supporting / ending receipt of transmissions from network node 16.

[0056] Although Figure 2 and Figure 3 Various "units" (such as PDC unit 32 and verification unit 34) are shown as being within respective processors, but it is contemplated that these units may be implemented such that a portion of the unit is stored in corresponding memory within the processing circuitry. In other words, the units may be implemented by hardware or by a combination of hardware and software within the processing circuitry.

[0057] Figure 4 FIG. 1 is a diagram illustrating a method for transmitting a signal to a communication system (eg, such as Figure 2 and Figure 2 The communication system may include a host computer 24, a network node 16, and a WD 22, which may be a reference Figure 3Those host computers, network nodes, and WDs described above. In the first step of the method, the host computer 24 provides user data (block S100). In an optional sub-step of the first step, the host computer 24 provides the user data by executing a host application (e.g., such as the host application 50) (block S102). In the second step, the host computer 24 initiates a transfer carrying the user data to the WD 22 (block S104). In accordance with the teachings of the embodiments described throughout this disclosure, in an optional third step, the network node 16 transmits the user data to the WD 22 (block S106), the user data being carried in the transfer initiated by the host computer 24. In an optional fourth step, the WD 22 executes a client application (e.g., such as the client application 92) associated with the host application 50 executed by the host computer 24 (block S108).

[0058] Figure 5 FIG. 1 is a diagram illustrating a method for transmitting a signal to a communication system (eg, such as Figure 2 The communication system may include a host computer 24, a network node 16, and a WD 22, which may be a reference Figure 2 and Figure 3 Those host computers, network nodes, and WDs described above. In the first step of the method, host computer 24 provides user data (block S110). In an optional sub-step (not shown), host computer 24 provides the user data by executing a host application (e.g., such as host application 50). In a second step, host computer 24 initiates a transmission carrying the user data to WD 22 (block S112). According to the teachings of the embodiments described throughout this disclosure, the transmission can be delivered via network node 16. In an optional third step, WD 22 receives the user data carried in the transmission (block S114).

[0059] Figure 6 FIG. 1 is a diagram illustrating a method for transmitting a signal to a communication system (eg, such as Figure 2 The communication system may include a host computer 24, a network node 16, and a WD 22, which may be a reference Figure 2 and Figure 3Those host computers, network nodes, and WDs described above. In an optional first step of the method, WD 22 receives input data provided by host computer 24 (block S116). In an optional sub-step of the first step, WD 22 executes client application 92, which reacts to the received input data provided by host computer 24 and provides user data (block S118). Additionally or alternatively, in an optional second step, WD 22 provides user data (block S120). In an optional sub-step of the second step, WD 22 provides user data by executing a client application (e.g., such as client application 92) (block S122). In providing user data, the executed client application 92 may further consider user input received from the user. Regardless of the specific manner in which the user data is provided, WD 22 initiates the transmission of the user data to host computer 24 in an optional third sub-step (block S124). In accordance with the teachings of the embodiments described throughout this disclosure, in a fourth step of the method, host computer 24 receives the user data transmitted from WD 22 (block S126).

[0060] Figure 7 FIG. 1 is a diagram illustrating a method for transmitting a signal to a communication system (eg, such as Figure 2 The communication system may include a host computer 24, a network node 16, and a WD 22, which may be a reference Figure 2 and Figure 3 In an optional first step of the method, network node 16 receives user data from WD 22 in accordance with the teachings of the embodiments described throughout this disclosure (block S128). In an optional second step, network node 16 initiates a transmission of the received user data to host computer 24 (block S130). In a third step, host computer 24 receives the user data carried in the transmission initiated by network node 16 (block S132).

[0061] Figure 81 is a flow chart of an example process in a network node 16 for propagation delay compensation for a wireless device (WD) in a radio resource control (RRC) idle or inactive state. One or more blocks described herein may be performed by one or more elements of the network node 16, such as one or more of the processing circuitry 68 (including the PDC unit 32), the processor 70, the radio interface 62, and / or the communication interface 60. The network node 16 is configured to configure the WD 22 to support propagation delay compensation (PDC) in one of the radio resource control (RRC) idle state and the RRC inactive state (block S134). The process also includes receiving a sounding reference signal (SRS) measurement from the WD 22, the SRS being based on a PDC value (block S136). The process also includes determining a PDC value based at least in part on the sounding reference signal measurement (block S138).

[0062] In some embodiments, the process further includes transmitting a pre-compensated clock time to WD 22, the pre-compensated clock time being based at least in part on the PDC value. In some embodiments, the method further includes configuring WD 22 to autonomously adjust the PDC value based at least in part on the time offset. In some embodiments, the method further includes configuring WD 22 to cease performing PDC upon changing cells. In some embodiments, the method further includes configuring WD 22 to autonomously adjust the PDC value based at least in part on the time difference in receiving downlink signals.

[0063] Figure 9 is a flow chart of an example process in the wireless device 22 according to some embodiments of the present invention. One or more blocks described herein may be performed by one or more elements of the wireless device 22, such as by one or more of the processing circuit 84 (including the verification unit 34), the processor 86, the radio interface 82, and / or the communication interface 60. The wireless device 22 is configured to receive a propagation delay compensation (PDC) value from a network node (Block S140). The process also includes verifying the PDC value based at least in part on a comparison of a difference in a sounding reference signal (SRS) measurement with a first threshold and a comparison of a difference in timing advance with a second threshold (Block S142).

[0064] In some embodiments, the PDC value is further verified based on a change in the channel state estimate over time. In some embodiments, the PDC value is further verified based on one of the position and rotation of WD22. In some embodiments, the PDC value is further verified based on a local primary time source. In some embodiments, the PDC value is based on a difference between a time offset in one of a radio resource control (RRC) active state and an RRC inactive state and an RRC idle state.

[0065] Figure 10is a flow chart of an example process in the wireless device 22 according to some embodiments of the present invention. One or more blocks described herein may be performed by one or more elements of the wireless device 22, such as by one or more of the processing circuit 84 (including the verification unit 34), the processor 86, the radio interface 82, and / or the communication interface 60. The wireless device 22 is configured to, when in a radio resource control (RRC) connected state, obtain a propagation delay compensation (PDC) configuration from the network node 16, the PDC configuration including a PDC value (S144). The method also includes, when in an RRC inactive or RRC idle state (S146): obtaining a time value signaled from the network node 16 (S148); determining whether the PDC value is valid (S150); and, when the PDC value is determined to be valid, using the PDC value to compensate for the time value signaled from the network node 16 (S152).

[0066] In some embodiments, the method includes, when the PDC value is determined to be invalid, entering an RRC connected state and obtaining a subsequent PDC configuration. In some embodiments, the method includes, when the PDC value is determined to be invalid, adjusting the PDC value while in an RRC idle state or an RRC inactive state. In some embodiments, adjusting the PDC value is based at least in part on: a change in the WD's position relative to the network node since the time the PDC value was obtained; a change in the time of reception of a downlink signal; or a change in a time offset from a local prime time. In some embodiments, the time value received from the network node 16 is Coordinated Universal Time (UTC) or Global Positioning System (GPS) time. In some embodiments, the method includes performing PDC based at least in part on the PDC value until the WD 22 changes cells. In some embodiments, determining whether the PDC value is valid is based at least in part on a detected signal measurement change that is less than a first threshold. In some embodiments, the signal measurement is one of reference signal received power, reference signal received quality, signal-to-interference-plus-noise ratio, and signal-to-noise ratio. In some embodiments, the detected signal measurement change includes a change between a first sample of a signal measurement performed at a first time and a second sample of the signal measurement performed at a second time after the first time, the first time being the time the PDC value was obtained. In some embodiments, the PDC value is determined to be invalid when the absolute value of the detected signal measurement change exceeds a second threshold. In some embodiments, determining whether the PDC value is valid includes comparing a time difference between receiving the first signal and receiving the second signal with a third threshold. In some embodiments, the first signal is one of a synchronization signal, a physical broadcast channel, a tracking reference signal, and a positioning reference signal from the cell where WD 22 is camped. In some embodiments, the second signal is one of a synchronization signal, a physical broadcast channel, a tracking reference signal, and a positioning reference signal from a neighboring cell to the cell where WD 22 is camped. In some embodiments, determining whether the PDC value is valid includes determining a change in signal measurements over a series of times. In some embodiments, determining whether the PDC value is valid includes comparing a change in at least one of the position and orientation of WD 22 with a fourth threshold. In some embodiments, determining whether the PDC value is valid includes comparing a time value signaled from network node 16 with a local primary time. In some embodiments, the local primary time is a global navigation satellite system time. In some embodiments, the PDC configuration includes at least one of a PDC method, permission to update the PDC value, a PDC verification method, and a time interval during which the PDC configuration is to be applied by WD 22. In some embodiments, the PDC method is one of a timing advance-based method and a round trip time-based method. In some embodiments, the round trip time-based method includes transmitting a sounding reference signal (SRS) in an RRC inactive state, and the WD is configured to receive a time difference value based on a measurement of the SRS by a network node.

[0067] Figure 11 1 is a flow chart of an example process in a network node 16 for propagation delay compensation for a wireless device (WD) in a radio resource control (RRC) idle or inactive state. One or more blocks described herein may be executed by one or more elements of the network node 16, such as by one or more of the processing circuitry 68 (including the PDC unit 32), the processor 70, the radio interface 62, and / or the communication interface 60. The network node 16 is configured to provide a propagation delay compensation (PDC) configuration to the WD 22 when the WD 22 is in a radio resource control (RRC) connected state (S154). The method also includes signaling a time value to the WD 22 when the WD 22 is in an RRC inactive state or an RRC idle state (S156). The PDC configuration includes a PDC value to be used by the WD 22 in the RRC inactive state or the RRC idle state to compensate for the time value when the WD 22 determines that the PDC value is valid (S158).

[0068] According to this aspect, in some embodiments, the time value transmitted by network node 16 is Coordinated Universal Time (UTC) or Global Positioning System (GPS) time. In some embodiments, the PDC configuration includes at least one of a PDC method, permission to update the PDC value, a PDC verification method, and a time interval during which the PDC configuration is to be applied by WD 22. In some embodiments, the PDC method is one of a timing advance-based method and a round-trip time-based method. In some embodiments, the method includes transmitting a next PDC configuration when WD 22 determines that the PDC value is invalid. In some embodiments, the method includes signaling a first threshold to WD 22 for comparison with a signal measurement or a change in signal measurement to determine whether the PDC value is valid. In some embodiments, the method includes configuring WD 22 to transmit a sounding reference signal (SRS) during an RRC inactive state. In some embodiments, the method includes configuring WD 22 to autonomously adjust the PDC value based at least in part on a time offset or a downlink signal reception time difference. In some embodiments, the method includes configuring WD 22 to cease performing PDC when WD 22 is changing cells.

[0069] Having described the general process flow of the arrangements of the present disclosure, and having provided examples of hardware and software arrangements for implementing the processes and functions of the present disclosure, the following section provides details and examples of arrangements for wireless device (WD) propagation delay compensation in a radio resource control (RRC) idle or inactive state.

[0070] One or more network node 16 functions described below may be performed by one or more of processing circuitry 68, processor 70, PDC unit 32, etc. One or more wireless device 22 functions described below may be performed by one or more of processing circuitry 84, processor 86, verification unit 34. Configure WD to perform PDC in RRC inactive / idle state

[0071] In some embodiments, WD 22 in the RRC connected state is configured to perform PDC at a time signaled by the network in a subsequent RRC inactive or idle state (eg, from a Global Positioning System (GPS) or UTC).

[0072] Some embodiments provide for configuration of one or more of a PDC method (eg, TA-based or RTT-based), a PDC value, permission to update the PDC value, a PDC verification method, and a time interval at which the configuration is applied. PDC Verification

[0073] In some embodiments, WD 22 assumes that a pre-configured or previously stored PDC value is verified based on a detected difference ΔS in the measured signal value that is no greater than a configured threshold. This threshold can be based on an additional allowance and assigned incremental error margin when performing PDC in connected mode. The margin can be selected to allow the air interface budget to be within the allowed portion of the total time allocation budget.

[0074] Examples of measurements are RSRP, Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), and Signal to Noise Ratio (SNR).

[0075] Examples of measurement signals are Primary and Secondary Synchronization Signals (PSS, SSS), Physical Broadcast Channel (PBCH), Tracking Reference Signal (TRS) and Positioning Reference Signal (PRS).

[0076] The difference in the measured value S is defined as the difference between a first sample S1 of the value measured at a first time and a second sample S2 measured at a later second time. The first time may correspond to the time when the WD 22 in the RRC connected state is configured by the network node to perform PDC in a subsequent RRC inactive state or idle state. The second later time may correspond to the time when the WD 22 intends to apply PDC to the received UTC in the RRC inactive state or idle state.

[0077] If the WD 22 detects a difference in the measured values ΔS=abs(S1-S2) that exceeds a threshold, the WD 22 considers the PDC to be outdated and invalid. Before continuing to perform PDC from the RRC inactive state or idle state, the WD 22 can obtain a new PDC configuration from the network / network node 16. The configured threshold can be set to an infinite value to allow the WD 22 to always perform PDC from the inactive state or idle state.

[0078] In some embodiments, the preconfigured PDC value is verified based on a difference ΔT of a first received signal time TA relative to a second received signal time TB, which second received signal time TB does not vary by more than a configured threshold.

[0079] Examples of the first received signal include a primary synchronization signal and a secondary synchronization signal (PSS, SSS), a physical broadcast channel (PBCH), a tracking reference signal (TRS), and a positioning reference signal (PRS) from the first cell where the WD 22 camps.

[0080] Examples of the second received signal include a primary synchronization signal and a secondary synchronization signal (PSS, SSS), a physical broadcast channel (PBCH), a tracking reference signal (TRS), and a positioning reference signal (PRS) from a second neighboring cell.

[0081] The change in the measured time difference dT is defined as the time difference ΔT1 between the first and second signals measured at a first time relative to the time difference ΔT2 between the first and second signals measured at a second time, i.e., dT = ΔT1 - ΔT2. The first measurement time may correspond to the time at which the WD 22 is configured by the network node 16 to perform PDC in a subsequent RRC inactive state or idle state. The second, later measurement time may correspond to the time at which the WD 22 intends to apply PDC to the received UTC in the RRC inactive state or idle state.

[0082] In some embodiments, the WD 22 may estimate the radio channel (e.g., based on received demodulation reference symbols (DMRS)) at multiple time instances and verify the PDC value based on detected changes in the estimated channel over time. For example, the channel may be represented as a tapped delay line (TDL), where each tap represents a received signal path. Changes in the timing, amplitude, or phase of the strongest channel tap and other taps in the TDL that exceed a threshold may be used as an indication that the WD 22 has moved. In some embodiments, this requires invalidating the pre-configured PDC value. Other ways to capture channel changes would be to detect changes in the center of gravity between channel estimates. (where P is the estimated total power, p i is the receiving time t iThe change in the center of gravity can be compared to a threshold. Some embodiments may employ a change in some function that defines how the distance between channels is measured. For example, if p 1,i and p 2,i is the channel power tap of the channel, and a function for different estimates of the channel at sampling time i can be defined, such as

[0083] In some embodiments, a pre-configured PDC value is validated based on a change in the device's position or rotation exceeding a threshold, thereby causing a channel change to the node that distributes the time information. The device's position change can be estimated based on an internal Global Navigation Satellite System (GNSS) receiver, for example, based on observed time differences of arrival from multiple base stations and an internal inertial measurement unit (IMU). The IMU can also be used to detect the rotation of the WD 22 using knowledge of the device's antenna characteristics to assess potential changes in channel conditions that could affect propagation delays.

[0084] In some embodiments, when the 5G system provides Time as a Service (Taas) as a backup to the primary time source, the pre-configured PDC value is verified by using another local primary time source (e.g., a local GNSS receiver). By comparing the time offset change from the primary source time reference of the 5G system time in RRC connected state (with updated PDC) and RRC inactive / idle state mode, the WD 22 can correlate the offset change from the primary source with the change in channel propagation delay.

[0085] Hereinafter, signaling and procedures of two methods of supporting propagation delay compensation (PDC): a TA-based method and an RTT-based method are described for WD22 in the RRC_INACTIVE state. TA-based approach in RRC_INACTIVE based on RSRP change verification

[0086] For the timing advance (TA) based method, a valid timing advance value can be obtained even if WD 22 is in RRC_INACTIVE state and there is little communication between WD 22 and the network node.

[0087] In some embodiments, a TA value obtained from an earlier procedure (e.g., from a Medium Access Control (MAC) timing advance command or from a random access procedure) is stored and may continue to be considered valid if certain conditions are met. These conditions indicate that the WD 22 has not moved too far from the location at which the stored TA value was estimated. Typical conditions include: (a) the channel measurement (e.g., RSRP, RSRQ, L1-RSRP) has not changed from the stored channel measurement by more than a predefined threshold; and (b) a timer set to track the freshness of the time alignment has not expired (i.e., the stored TA value is not too old).

[0088] In the following, Figure 12 Example MAC procedure in, where sync-RSRP-ChangeThreshold represents an RRC parameter that ensures that the channel measurement has not changed significantly compared to the channel conditions when the stored TA value was estimated; sync-TimeAlignmentTimer represents an RRC parameter that ensures that too much time has not passed since the time the TA value was estimated and stored.

[0089] The MAC entity can be configured as follows: 1> If WD 22 receives an indication to move from RRC_CONNECTED to RRC_INACTIVE: 2>Store the RSRP of the downlink path loss reference and the current RSRP value of the downlink path loss reference; 1> If a timing advance command MAC CE is received, or; 1> If a timing advance command or absolute timing advance command is received for a successfully completed random access procedure: 2> Update the stored downlink path loss reference using the current RSRP value of the downlink path loss reference.

[0090] When WD 22 is in RRC_INACTIVE, the MAC entity may be configured to consider the most recently stored TA to be valid if the following conditions are met: 1> The current RSRP value of the downlink path loss reference has not increased / decreased by more than the sync-RSRP-ChangeThreshold (if configured) compared to the stored downlink path loss reference RSRP value; and 1>sync-TimeAlignmentTimer is running.

[0091] If the most recently stored TA is verified as described above, WD 22 may use the verified TA value to derive a propagation delay compensation value to obtain synchronized clock time at WD 22 .

[0092] In the above process, it is assumed that WD22 is the entity that obtains the stored TA value and performs propagation delay compensation.

[0093] Alternatively, it is also possible that network node 16 verifies the stored TA value and performs pre-compensation of the 5GS clock using the stored TA, and then network node 16 sends the compensated clock time to WD 22. With the pre-compensation of the network node, WD 22 can directly receive and use the clock time, so WD 22 does not need to perform propagation delay compensation). RTT-based method in RRC_INACTIVE

[0094] For propagation delay compensation at WD: The network node 16 may configure the WD 22 to transmit periodic or semi-persistent positioning sounding reference signals (SRS) in the RRC_INACTIVE state. The network node 16 may then determine the network node RxTxTimDiff based on measurements of the positioning SRS. Next, as part of a small data transmission (SDT), the network node 16 may send the network node RxTxTimeDiff value to the WD 22 in the RRC inactive or idle state.

[0095] At the same time, WD 22 can measure the serving cell's positioning reference signal (PRS) to obtain WDRxTxTimeDiff. Using the network node RxTxTimeDiff value and the WDRxTxTimeDiff value, WD 22 can derive a propagation delay compensation value, thereby obtaining the synchronized clock time at WD 22.

[0096] For propagation delay compensation at network nodes: WD 22 can measure the serving cell's Positioning Reference Signal (PRS) to obtain WD RxTxTimeDiff. WD 22 in the RRC Inactive or Idle state then sends its estimated WD RxTxTimeDiff value to the network node as part of a Small Data Transfer (SDT).

[0097] When WD 22 is in RRC_INACTIVE mode, the network node can configure WD 22 to transmit periodic or semi-persistent positioning SRS. Network node 16 can determine network node RxTxTimDiff based on measurements of the positioning SRS. Using the network node RxTxTimeDiff value and the WD RxTxTimeDiff value, network node 16 can derive a propagation delay compensation value and pre-compensate the target WD 22 for 5 GS clock time. Network node 16 can then send the pre-compensated clock time to the target WD 22 in a dedicated message. WD 22 automatic PDC adjustment

[0098] In some embodiments, WD 22 is configured to autonomously adjust its pre-configured PDC value in the RRC idle or inactive state. Positioning-based methods

[0099] WD 22 can update the previous PDC value P1 based on the known change in position, distance d, relative to the network node 16 where WD 22 resides since the time PDC P1 was obtained. The new, updated PDC value P2 can be calculated as P2 = P1 + d / c, where c equals the speed of light. This can be done as WD 22 increases its distance from the resident network node providing the broadcast UTC. If the distance to the base station decreases, the new PDC is calculated as: P2 = P1 - d / c.

[0100] The distance d may be based on WD22 obtaining the base station position via higher layer signaling, and obtaining its own position by using GNSS. Downlink timing change method

[0101] In some embodiments, WD22 is configured to autonomously adjust to perform PDC based on the time difference of receiving the downlink signal. If the downlink signal drifts over time, WD22 can determine that WD22 has moved and the downlink propagation delay has changed. For example, if WD22 moves away from a network node, the downlink signal received from that node will arrive later (compared to when WD22 is not moving). WD22 can measure this change in downlink timing and estimate the DL propagation delay to calculate the downlink timing. If the DL timing is delayed by an increment D, WD22 can calculate the time as the time notified by the received law signal + D. Main time source reference method

[0102] In some embodiments, when the 5G system provides Time as a Service (Taas) as a backup to the primary time source, the WD 22 is configured to autonomously adjust the PDC based on changes in time offset from another local primary time source (e.g., a local GNSS receiver). By comparing the time offset change from the 5G system time in the RRC connected state (with updated PDC) to the RRC inactive / idle state toward the primary source time reference, the WD 22 can correlate the offset change from the primary source with changes in channel propagation delay and compensate for it. Cell reselection

[0103] In some embodiments, WD 22 can be configured to stop performing PDC when changing cells. If WD 22 is connected to a first cell and is determined to be performing PDC while idle / inactive, WD 22 can stop performing PDC when changing to a second cell. WD 22 can also consider the current time information invalid during cell reselection. WD 22 can reacquire a new PDC value when changing cells and then resume PDC.

[0104] In some embodiments, WD 22 may measure a time offset when receiving the time from the first cell and the time from the second cell, and use the offset to compensate for the PDC associated with the first cell, and use the compensated PDC when receiving the time from the second cell. Such an approach may be conditional on the time error between cells (between cell antenna reference points) being below a threshold, and therefore the time difference being primarily related to the radio frequency (RF) propagation delay difference.

[0105] A node may be hosting multiple cells. In this scenario, timing information received from one cell of the node may be applicable when WD 22 is currently camping on another cell supported by the same node. Therefore, when WD 22 is in a second cell but not a third cell, WD 22 may determine that timing information from the first cell can be applied. The network may indicate the cell(s) to which WD 22 may move if the timing information received from the first cell is deemed valid. This may be indicated, for example, in the configuration.

[0106] Some embodiments may include one or more of the following: Embodiment A1. A network node configured to communicate with a wireless device (WD), the network node being configured to and / or comprising a radio interface and / or comprising a processing circuit configured to: Configuring the WD to support propagation delay compensation (PDC) in one of the radio resource control (RRC) idle state and the RRC inactive state receiving a sounding reference signal (SRS) measurement from a WD, the SRS being based at least in part on a PDC value; and A PDC value is determined based at least in part on the sounding reference signal measurements.

[0107] Embodiment A2. The network node of Embodiment A1, wherein the network node, radio interface, and / or processing circuitry is further configured to transmit a pre-compensated clock time to the WD, the pre-compensated clock time being based at least in part on the PDC value.

[0108] Embodiment A3. The network node of any of embodiments A1 and A2, wherein the network node, radio interface, and / or processing circuitry is further configured to configure the WD to autonomously adjust the PDC value based at least in part on the time offset.

[0109] Embodiment A4. The network node of any one of embodiments A1-A3, wherein the network node, radio interface, and / or processing circuitry is further configured to configure the WD to stop performing PDC when changing cells.

[0110] Embodiment A5. The network node of any of embodiments A1-A4, wherein the network node, radio interface, and / or processing circuitry is further configured to configure the WD to autonomously adjust the PDC value based at least in part on a reception time difference of a downlink signal.

[0111] Embodiment B1. A method implemented in a network node, the method comprising: The WD is configured to support propagation delay compensation (PDC) in one of a radio resource control (RRC) idle state and an RRC inactive state. receiving a sounding reference signal (SRS) measurement from a WD, the SRS being based at least in part on a PDC value; and A PDC value is determined based at least in part on the sounding reference signal measurements.

[0112] Embodiment B2. The method of embodiment B1, further comprising transmitting a pre-compensated clock time to the WD, the pre-compensated clock time being based at least in part on the PDC value.

[0113] Embodiment B3. The method of any of embodiments B1 and B2, further comprising configuring the WD to autonomously adjust the PDC value based at least in part on the time offset.

[0114] Embodiment B4. The method of any one of embodiments B1-B3, further comprising configuring the WD to stop performing PDC when changing cells.

[0115] Embodiment B5. The method of any one of embodiments B1-B4, further comprising configuring the WD to autonomously adjust the PDC value based at least in part on a reception time difference of the downlink signal.

[0116] Embodiment C1. A wireless device (WD) configured to communicate with a network node, the WD configured to and / or including a radio interface and / or processing circuitry configured to: receiving a propagation delay compensation (PDC) value from a network node; and The PDC value is validated based at least in part on one of a comparison of a difference in sounding reference signal (SRS) measurements to a first threshold and a comparison of a difference in timing advance to a second threshold.

[0117] Embodiment C2. The WD of embodiment C1, wherein the verification of the PDC value is further based on changes in the channel state estimate over time.

[0118] Embodiment C3. The WD according to any one of embodiments C1 and C2, wherein the verification of the PDC value is further based on one of the position and rotation of the WD.

[0119] Embodiment C4. The WD of any one of embodiments C1-C3, wherein the validation of the PDC value is further based on a local primary time source.

[0120] Embodiment C5. The WD of any one of embodiments C1-C3, wherein the PDC value is based on a difference between a time offset in a radio resource control (RRC) active state and one of an RRC inactive state and an RRC idle state.

[0121] Embodiment D1. A method implemented in a wireless device (WD), the method comprising: receiving a propagation delay compensation (PDC) value from a network node; and The PDC value is validated based at least in part on one of a comparison of a difference in sounding reference signal (SRS) measurements to a first threshold and a comparison of a difference in timing advance to a second threshold.

[0122] Embodiment D2. The method of embodiment D1, wherein the verification of the PDC value is further based on changes in the channel state estimate over time.

[0123] Embodiment D3. The method of any one of embodiments D1 and D2, wherein the verification of the PDC value is further based on one of the position and the rotation of the WD.

[0124] Embodiment D4. The method of any of embodiments D1-D3, wherein the verification of the PDC value is further based on a local primary time source.

[0125] Embodiment D5. The method of any one of embodiments D1-D3, wherein the PDC value is based on a difference between a time offset in a radio resource control (RRC) active state and one of an RRC inactive state and an RRC idle state.

[0126] As will be appreciated by those skilled in the art, the concepts described herein can be embodied as methods, data processing systems, computer program products, and / or computer storage media storing executable computer programs. Thus, the concepts described herein can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining all software and hardware aspects, generally referred to herein as "circuits" or "modules." Any process, step, action, and / or functionality described herein can be performed by a corresponding module and / or can be associated with a corresponding module, which can be implemented using software and / or firmware and / or hardware. Furthermore, the disclosure can take the form of a computer program product on a tangible computer-usable storage medium having computer program code embodied in the medium that can be executed by a computer. Any suitable tangible computer-readable medium can be utilized, including a hard disk, CD-ROM, electronic storage device, optical storage device, or magnetic storage device.

[0127] Some embodiments are described herein with reference to flowchart illustrations and / or block diagrams of methods, systems, and computer program products. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer (thereby creating a special-purpose computer), a processor of a special-purpose computer, or other programmable data processing device to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing device create components for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0128] These computer program instructions that can direct a computer or other programmable data processing device to operate in a specific manner may also be stored in a computer-readable memory or storage medium, so that the instructions stored in the computer-readable memory produce an article of manufacture including instruction components that implement the functions / actions specified in one or more boxes of the flowchart and / or block diagram.

[0129] The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, such that the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions / actions specified in one or more boxes of the flowchart and / or block diagram.

[0130] It is to be understood that the functions / actions annotated in the blocks may not occur in the order annotated in the operational instructions. For example, depending on the functionality / actions involved, two blocks shown in succession may actually be executed substantially simultaneously, or the blocks may sometimes be executed in the reverse order. Although some of the figures include arrows on communication paths to illustrate the primary direction of communication, it is to be understood that communication may occur in the opposite direction of the depicted arrows.

[0131] You can use Python, In one embodiment, the computer program code for performing the operation of the concept described herein can be written in an object-oriented programming language such as C or C++. However, the computer program code for performing the disclosed operation can also be written in a conventional procedural programming language such as the "C" programming language. The program code can be performed completely on the user's computer, partially on the user's computer, performed as an independent software package, partially on the user's computer and partially on a remote computer, or performed completely on the remote computer. In the latter scenario, the remote computer can be connected to the user's computer through a local area network (LAN) or a wide area network (WAN), or (for example, utilizing an Internet service provider to pass through the Internet) can be made to be connected to an external computer.

[0132] Many different embodiments have been disclosed herein in conjunction with the above description and figures. It will be understood that literally describing and illustrating every combination and subcombination of these embodiments would be unduly repetitive and obscure. Therefore, all embodiments may be combined in any manner and / or combination, and this specification, including the figures, should be construed as constituting a complete written description of all combinations and subcombinations of the embodiments described herein, as well as the manner and process of making and using them, and this specification, including the figures, should support claims to any such combination or subcombination.

[0133] Abbreviations that may be used in the preceding description include: 3GPP Third Generation Partnership Project 5GS 5G system NR New Radio PDC Propagation Delay Compensation RRC Radio Resource Control SDT Small Data Transfer Taas Time as a Service TSN Time-Sensitive Networking UTC Coordinated Universal Time

[0134] Those skilled in the art will appreciate that the embodiments described herein are not limited to what has been particularly shown and described hereinabove. In addition, unless otherwise indicated above, it should be noted that none of the figures in the accompanying drawings are drawn to scale. Various modifications and variations are possible in light of the above teachings without departing from the scope of the appended claims.

Claims

1. A method in a wireless device WD (22) configured to communicate with a network node (16), the method comprising: while in a Radio Resource Control, RRC, connected state, obtaining (S144) a propagation delay compensation, PDC, configuration from said network node (16), said PDC configuration comprising a PDC value; and When in RRC inactive or RRC idle state (S146): obtaining (S148) a time value signaled from said network node (16); determining (S150) whether the PDC value is valid; and When the PDC value is determined to be valid (S152), the time value signaled from the network node (16) is compensated using the PDC value.

2. The method of claim 1, further comprising: When the PDC value is determined to be invalid, the RRC connected state is entered and subsequent PDC configuration is acquired.

3. The method of claim 1 , further comprising: When the PDC value is determined to be invalid, the PDC value is adjusted in the RRC idle state or the RRC inactive state.

4. The method according to claim 3, wherein: Adjusting the PDC value is based at least in part on: a change in position of the WD relative to the network node since the time when the PDC value was obtained; Variation in the reception time of the downlink signal; or A change in time offset from local prime time.

5. The method according to any one of claims 1 to 4, wherein The time value signaled from the network node (16) is Coordinated Universal Time UTC or Global Positioning System GPS time.

6. The method of any of claims 1-5, further comprising performing PDC based at least in part on the PDC value until the WD (22) changes cells.

7. The method according to any one of claims 1 to 6, wherein Determining whether the PDC value is valid is based at least in part on a detected signal measurement change being less than a first threshold.

8. The method of claim 7, wherein: The signal measurement is one of a reference signal received power, a reference signal received quality, a signal to interference plus noise ratio, and a signal to noise ratio.

9. The method of claim 7, wherein: The detected change in signal measurement includes a change between a first sample of the signal measurement performed at a first time and a second sample of the signal measurement performed at a second time after the first time, the first time being when the PDC value is obtained.

10. The method of claim 7, wherein: When the absolute value of the detected signal measurement change exceeds a second threshold, the PDC value is determined to be invalid.

11. The method according to any one of claims 1 to 10, wherein Determining whether the PDC value is valid includes comparing a time difference between receiving the first signal and receiving the second signal to a third threshold.

12. The method of claim 11, wherein: The first signal is one of a synchronization signal, a physical broadcast channel, a tracking reference signal, and a positioning reference signal from a cell where the WD (22) resides.

13. The method according to any one of claims 10 to 12, wherein: The second signal is one of a synchronization signal, a physical broadcast channel, a tracking reference signal, and a positioning reference signal from a neighboring cell to the cell where the WD (22) resides.

14. The method according to any one of claims 1 to 13, wherein Determining whether the PDC value is valid includes determining a change in signal measurements over a series of times.

15. The method according to any one of claims 1 to 14, wherein Determining whether the PDC value is valid includes comparing a change in at least one of a position and an orientation of the WD (22) to a fourth threshold.

16. The method according to any one of claims 1 to 15, wherein Determining whether the PDC value is valid includes comparing a PDC compensated version of the time value signaled from the network node (16) to a local primary time.

17. The method of claim 16, wherein: The local primary time is the Global Navigation Satellite System time.

18. The method according to any one of claims 1 to 17, wherein The PDC configuration includes at least one of a PDC method, permission to update the PDC value, a PDC verification method, and a time interval during which the PDC configuration is to be applied by the WD (22).

19. The method of claim 18, wherein: The PDC method is one of a timing advance-based method and a round trip time-based method.

20. The method of claim 19, wherein: The round trip time based method comprises transmitting a sounding reference signal (SRS) in an RRC inactive state, and wherein the time difference value is received based on a measurement of the SRS by the network node.

21. A wireless device WD (22) configured to communicate with a network node (16), the WD (22) being configured to: while in a radio resource control (RRC) connected state, obtaining a propagation delay compensation (PDC) configuration from the network node (16), the PDC configuration comprising a PDC value; and When in RRC Inactive or RRC Idle state: obtaining a time value signaled from the network node (16); determining whether the PDC value is valid; and When the PDC value is determined to be valid, the time value signaled from the network node (16) is compensated using the PDC value.

22. The WD (22) according to claim 2, wherein When the PDC value is determined to be invalid, the RRC connected state is entered and subsequent PDC configuration is acquired.

23. The WD (22) according to claim 21, wherein When the PDC value is determined to be invalid, the PDC value is adjusted in the RRC idle state or the RRC inactive state.

24. The WD (22) of claim 23, wherein: Adjusting the PDC value is based at least in part on: a change in position of the WD relative to the network node since the time when the PDC value was obtained; Variation in the reception time of the downlink signal; or A change in time offset from local prime time.

25. The WD (22) according to any one of claims 21 to 24, wherein The time value received from the network node (16) is Coordinated Universal Time UTC or Global Positioning System GPS time.

26. The WD (22) according to any one of claims 21 to 25, wherein The WD (22) is configured to perform PDC based at least in part on the PDC value until the WD (22) changes cells.

27. The WD (22) according to any one of claims 21 to 26, wherein Determining whether the PDC value is valid is based at least in part on a detected signal measurement change being less than a first threshold.

28. The WD (22) of claim 27, wherein: The signal measurement is one of a reference signal received power, a reference signal received quality, a signal to interference plus noise ratio, and a signal to noise ratio.

29. The WD (22) of claim 27, wherein: The detected change in signal measurement includes a change between a first sample of the signal measurement performed at a first time and a second sample of the signal measurement performed at a second time after the first time, the first time being when the PDC value is obtained.

30. The WD (22) of claim 27, wherein: When the absolute value of the detected signal measurement change exceeds a second threshold, the PDC value is determined to be invalid.

31. The WD (22) of any one of claims 21 to 30, wherein Determining whether the PDC value is valid includes comparing a time difference between receiving the first signal and receiving the second signal to a third threshold.

32. The WD (22) of claim 31, wherein The first signal is one of a synchronization signal, a physical broadcast channel, a tracking reference signal, and a positioning reference signal from a cell where the WD (22) resides.

33. The WD (22) of any one of claims 31 , wherein The second signal is one of a synchronization signal, a physical broadcast channel, a tracking reference signal, and a positioning reference signal from a neighboring cell to the cell where the WD (22) resides.

34. The WD (22) of any one of claims 21 to 33, wherein Determining whether the PDC value is valid includes determining a change in signal measurements over a series of times.

35. The WD (22) of any one of claims 21 to 34, wherein Determining whether the PDC value is valid includes comparing a change in at least one of a position and an orientation of the WD (22) to a fourth threshold.

36. The WD (22) of any one of claims 21 to 35, wherein Determining whether the PDC value is valid includes comparing a PDC compensated version of the time value signaled by the network node (16) to a local primary time.

37. The WD (22) of claim 36, wherein The local primary time is the Global Navigation Satellite System time.

38. The WD (22) of any one of claims 21 to 37, wherein The PDC configuration includes at least one of a PDC method, permission to update the PDC value, a PDC verification method, and a time interval during which the PDC configuration is to be applied by the WD (22).

39. The WD (22) of claim 38, wherein The PDC method is one of a timing advance-based method and a round trip time-based method.

40. The WD (22) of claim 39, wherein The round trip time based method includes transmitting a sounding reference signal (SRS) in an RRC inactive state, and the WD is configured to receive a time difference value based on a measurement of the SRS by the network node.

41. A method in a network node (16) configured to communicate with a wireless device WD (22), the method comprising: providing a propagation delay compensation PDC configuration to the WD (22) when the WD (22) is in a radio resource control RRC connected state (S154); as well as When the WD (22) is in an RRC inactive state or an RRC idle state (S156), signaling a time value to the WD (22); The PDC configuration includes a PDC value to be used by the WD (22) in the RRC inactive state or the RRC idle state to compensate for the time value when the PDC value is determined to be valid by the WD (22) (S158).

42. The method of claim 41, wherein The time value transmitted by the network node (16) is Coordinated Universal Time UTC or Global Positioning System GPS time.

43. The method of any one of claims 41 and 42, wherein The PDC configuration includes at least one of a PDC method, permission to update the PDC value, a PDC verification method, and a time interval during which the PDC configuration is to be applied by the WD (22).

44. The method of claim 43, wherein The PDC method is one of a timing advance-based method and a round trip time-based method.

45. The method of any one of claims 41-44, further comprising providing subsequent PDC configuration when the WD (22) determines that the PDC value is invalid.

46. The method of any one of claims 41-45, further comprising signaling a first threshold to the WD (22) to compare with a signal measurement or a change in signal measurement to determine whether the PDC value is valid.

47. The method of any of claims 41-45, further comprising configuring the WD (22) to transmit a sounding reference signal (SRS) during the RRC inactive state.

48. The method of any of claims 41-47, further comprising configuring the WD (22) to autonomously adjust the PDC value based at least in part on a time offset or a downlink signal reception time difference.

49. The method of any one of claims 41-48, further comprising configuring the WD (22) to stop performing PDC when the WD (22) is changing cells.

50. A network node (16) configured to communicate with a wireless device WD (22), the network node (16) being configured to: providing a propagation delay compensation (PDC) configuration to the WD (22) when the WD (22) is in a radio resource control (RRC) connected state; and signaling a time value to the WD (22) when the WD (22) is in an RRC inactive state or an RRC idle state; The PDC configuration includes a PDC value to be used by the WD (22) in the RRC inactive state or the RRC idle state to compensate for the time value when the PDC value is determined by the WD (22) to be valid.

51. The network node (16) of claim 50, wherein: The time value transmitted by the network node (16) is Coordinated Universal Time UTC or Global Positioning System GPS time.

52. The network node (16) of any one of claims 50 and 51, wherein The PDC configuration includes at least one of a PDC method, permission to update the PDC value, a PDC verification method, and a time interval during which the PDC configuration is to be applied by the WD (22).

53. The network node (16) of claim 52, wherein: The PDC method is one of a timing advance-based method and a round trip time-based method.

54. The network node (16) according to any one of claims 50 to 53, wherein: The network node (16) is further configured to provide subsequent PDC configuration when the WD (22) determines that the PDC value is invalid.

55. The network node (16) according to any one of claims 50 to 54, wherein The network node (16) is configured to signal a first threshold to the WD (22) to compare with a signal measurement or a change in signal measurement to determine whether the PDC value is valid.

56. The network node (16) according to any one of claims 50 to 54, wherein The network node (16) is configured to configure the WD (22) to transmit a sounding reference signal (SRS) during the RRC inactive state.

57. The network node (16) according to any one of claims 50 to 56, wherein The network node (16) is configured to configure the WD (22) to autonomously adjust the PDC value based at least in part on a time offset or a downlink signal reception time difference.

58. The network node (16) according to any one of claims 50 to 57, wherein The network node (16) is configured to configure the WD (22) to stop performing PDC when the WD (22) is changing cells.

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