WO2023245607A1

WO2023245607A1 - Positioning configuration update

Info

Publication number: WO2023245607A1
Application number: PCT/CN2022/101062
Authority: WO
Inventors: Yan Meng; Tao Tao; Jianguo Liu; Nuan SONG
Original assignee: Nokia Shanghai Bell Co., Ltd.
Priority date: 2022-06-24
Filing date: 2022-06-24
Publication date: 2023-12-28

Abstract

Various example embodiments relate to methods and apparatuses for positioning configuration update. An apparatus may be configured to receive an indication of a deferred timer by which release of an RRC connection between a terminal device and a network device is deferred, send to the network device or a location server a request for positioning configuration update in response to the indication of the deferred timer, and switch to an RRC inactive or idle status when the positioning configuration update is received at the terminal device or the deferred timer expires.

Description

POSITIONING CONFIGURATION UPDATE

TECHNICAL FIELD

Various example embodiments described herein generally relate to communication technologies, and more particularly, to methods and apparatuses for updating positioning configuration for terminal devices in a wireless communication system.

BACKGROUND

Certain abbreviations that may be found in the description and/or in the figures are herewith defined as follows:

DL Downlink

DRX Discontinuous Reception

gNB next Generation Node-B

LMC Location Management Component

LMF Location Management Function

LPHAP Low Power High Accuracy Positioning

LPP LTE Positioning Protocol

NR New Radio

NRPPa NR Positioning Protocol A

PRS Positioning Reference Signal

QoS Quality of Service

RAN Random Access Network

RRC Radio Resource Control

SRS Sounding Reference Signal

TRP Transmission Reception Point

UE User Equipment

UL Uplink

Wireless communication systems have developed through various generations, and can support various types of service applications for terminal devices. For some applications, it may be useful to be able to obtain a position of a terminal device through a wireless communication system, so that a large number of position-based services (e.g., emergency calls, navigation assistance, asset tracking, etc. ) can be provided. In some scenarios and/or for certain categories of terminal device, it may be desirable to position a terminal device in a reduced power consumption state.

SUMMARY

A brief summary of exemplary embodiments is provided below to provide basic understanding of some aspects of various embodiments. It should be noted that this summary is not intended to identify key features of essential elements or define scopes of the embodiments, and its sole purpose is to introduce some concepts in a simplified form as a preamble for a more detailed description provided below.

In a first aspect, an example embodiment of a terminal device is provided. The terminal device may comprise at least one processor and at least one memory including computer program code. The at least one memory and the computer program code may be configured to, with the at least one processor, cause the terminal device at least to receive from a network device an indication of a deferred timer by which release of a radio resource control (RRC) connection between the terminal device and the network device is deferred, send to the network device or a location server a request for positioning configuration update in response to the indication of the deferred timer, and switch to an RRC inactive or idle status when the positioning configuration update is received at the terminal device or the deferred timer expires.

In a second aspect, an example embodiment of a network device is provided. The network device may comprise at least one processor and at least one memory including computer program code. The at least one memory and the computer program code may be configured to, with the at least one processor, cause the network device at least to decide to defer release of a radio resource control (RRC) connection between the network device and a terminal device, and send to the terminal device an indication of a deferred timer by which release of the RRC connection between the network device and the terminal device is deferred.

In a third aspect, an example embodiment of a location server is provided. The location server may comprise at least one processor and at least one memory including computer program code. The at least one memory and the computer program code may be configured to, with the at least one processor, cause the location server at least to receive from a terminal device or a network device a request of positioning configuration update for the terminal device. The request may comprise a response timer. The location server may send to the terminal device or the network device positioning configuration update for the terminal device before the response timer expires.

Example embodiments of methods, apparatus and computer program products are also provided. Such example embodiments generally correspond to the example embodiments in the above aspects and a repetitive description thereof is omitted here for convenience.

Other features and advantages of the example embodiments of the present disclosure will also be apparent from the following description of specific embodiments when read in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of example embodiments of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

Some example embodiments will now be described, by way of non-limiting examples, with reference to the accompanying drawings.

Fig. 1 is a schematic diagram illustrating a wireless communication network in which example embodiments of the present disclosure can be implemented.

Fig. 2 is a UE Radio Resource Control (RRC) state machine and state transitions in NR.

Fig. 3 is high-level message flow diagram illustrating a positioning configuration update process according to an example embodiment of the present disclosure.

Fig. 4 is a schematic message flow diagram illustrating a positioning assistance data configuration update process for DL positioning according to an example embodiment of the present disclosure.

Fig. 5 is a schematic message flow diagram illustrating an SRS configuration update process for UL positioning according to an example embodiment of the present disclosure.

Fig. 6 is a schematic flowchart illustrating a positioning configuration update method implemented at a terminal device according to an example embodiment of the present disclosure.

Fig. 7 is a schematic flowchart illustrating a positioning configuration update method implemented at a network device according to an example embodiment of the present disclosure.

Fig. 8 is a schematic flowchart illustrating a positioning configuration update method implemented at a location server according to an example embodiment of the present disclosure.

Fig. 9 is a schematic structure block diagram illustrating devices in a communication system in which example embodiments of the present disclosure can be implemented.

Throughout the drawings, same or similar reference numbers indicate same or similar elements. A repetitive description on the same elements would be omitted.

DETAILED DESCRIPTION

Herein below, some example embodiments are described in detail with reference to the accompanying drawings. The following description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known circuits, techniques and components are shown in block diagram form to avoid obscuring the described concepts and features.

As used herein, the term “terminal device” or “user equipment” (UE) refers to any entities or devices that can wirelessly communicate with the network devices or with each other. Examples of the terminal device can include a mobile phone, a mobile terminal (MT) , a mobile station (MS) , a subscriber station (SS) , a portable subscriber station (PSS) , an access terminal (AT) , a computer, a wearable device, an on-vehicle communication device, a machine type communication (MTC) device, a D2D communication device, a V2X communication device, a sensor and the like. The term “terminal device” can be used interchangeably with a UE, a user terminal, a mobile terminal, a mobile station, or a wireless device.

As used herein, the term “network device” refers to any suitable entities or devices that can provide cells or coverage, through which the terminal device can access the network or receive services. The network device may be commonly referred to as a base station. The term “base station” used herein can represent a node B (NodeB or NB) , an evolved node B (eNodeB or eNB) , or a gNB. The base station may be embodied as a macro base station, a relay node, or a low power node such as a pico base station or a femto base station. The base station may consist of several distributed network units, such as a central unit (CU) , one or more distributed units (DUs) , one or more remote radio heads (RRHs) or remote radio units (RRUs) . The number and functions of these distributed units depend on the selected split RAN architecture.

As used herein, the term “network function” (NF) refers to a processing function in a network, and defines a functional behavior and an interface. The network function may be implemented by using dedicated hardware, or may be implemented by running software on dedicated hardware, or may be implemented on a form of a virtual function on a common hardware platform. From a perspective of implementation, network functions may be classified into a physical network function and a virtual network function. From a perspective of use, network functions may be classified into a dedicated network function and a shared network function.

Fig. 1 illustrates a simplified schematic diagram of a cellular communication network 100 in which example embodiments of the present disclosure can be implemented. The cellular communication network 100 may be implemented as a multiple access system capable of supporting communication with multiple users sharing available system resources. The cellular communication network 100 may employ one or more channel access schemes such as Time Division Multiple Access (TDMA) , Code Division Multiple Access (CDMA) , Time Division Synchronous Code Division Multiple Access (TD-SCDMA) , Frequency Division Multiple Access (FDMA) , Orthogonal Frequency Division Multiple Access (OFDMA) , Single Carrier Frequency Division Multiple Access (SC-FDMA) and the like. These multiple access schemes may be formulated in 4G Long Term Evolution (LTE) , 5G New Radio (NR) , or beyond 5G radio standards. For convenience of description, Fig. 1 shows the cellular communication network 100 as a 5G NR network including a plurality of 5G base stations “gNB” , but it would be appreciated that example embodiments disclosed herein can also be implemented in a 4G LTE network or a beyond 5G network.

Referring to Fig. 1, the communication network 100 may include a user equipment (UE) 110 and a plurality of base stations (shown as gNBs) 120a, 120b, 120c. The plurality of

base stations

120a, 120b, 120c, collectively referred to as base stations 120, may form a so-called radio access network (RAN) and provide network access to a plurality of UEs. For example, the UE 110 may camp in a cell supported by the base station 120a and establish a radio resource control (RRC) connection with the base station 120a. The UE 110 may communicate with the base station 120a on uplink and downlink channels. The base station 120a may be referred to as a serving base station for the UE 110, and the

base stations

120b, 120c may be referred to as neighbor base stations.

In some example embodiments, the communication network 100 may employ a multiple transmission reception point (mTRP) architecture where the UE 110 can transmit data to and receive data from one or more transmission reception points (TRPs) . The TRPs may be associated with one or more base stations 120 and/or one more cells. The term “cell” used herein may refer to a particular geographic coverage area served by a base station and/or a subsystem of the base station serving the coverage area, depending on the context in which the term is used. It would be appreciated that when the description herein indicates that a “cell” performs functions, a base station serving the cell would perform the functions. Example embodiments described herein are not limited to any particular deployment of the TRPs or a particular relationship between the TRPs and the base stations/cells. It would also be appreciated that throughout the present disclosure, the term “base station” may also comprise a TRP, and operations performed at a base station may be performed at least partially at a TRP.

With continuous reference to Fig. 1, the communication network 100 may further comprise a location server 130 to manage positioning of UEs connected to the network 100. The location server 130 may be a physical or logical entity which may be implemented as a local location management component (LMC) in a base station or as a location management function (LMF) within a core network. The base stations 120 may connect to the core network through so called backhaul connections.

Positioning methods can be classified as “uplink” (UL) positioning, “downlink” (DL) positioning, and “uplink and downlink” (UL-DL) positioning. A UL positioning method makes use of UL positioning reference signals (PRSs) transmitted by the UE 110 to the serving base station 120a and one or more neighbor base stations such as the

base station

120b, 120c. The

base station

120a, 120b, and 120c may obtain position measurements based on the UL PRSs and then send a measurement report to the location server 130 for determination of the position of the UE 110. A DL positioning method makes use of DL PRSs transmitted by one or

more base stations

120a, 120b, 120c. The DL PRSs are obtained by the UE 110 to estimate its position. Alternatively, the UE 110 may send a measurement report based on the DL PRSs to the location server 130 to determine the position of the UE 110. A UL-DL positioning method makes use of both UL PRSs transmitted by the UE 110 and DL PRSs received by the UE 110. Throughout the present disclosure, the terms “positioning reference signal” and “PRS” may refer to any uplink or downlink positioning reference signal which can be used to perform positioning measurements. For example, UL PRS may include the sounding reference signal (SRS) , physical random-access channel (PRACH) , UL demodulation reference signal (DMRS) , UL phase tracking reference signal (PTRS) , and any other positioning reference signal for UL positioning defined in 3GPP specifications, and DL PRS may include the synchronization signal block (SSB) , the cell-specific reference signal (CRS) , the tracking reference signal (TRS) , and any other positioning reference signal for DL positioning defined in 3GPP specifications.

A wide variety of cellular network-based positioning methods are supported for NR, including but not limited to Downlink Time Difference of Arrival (DL-TDOA) , Uplink Time Difference of Arrival (UL-TDOA) , Downlink Angle of Departure (DL-AoD) , Uplink Angle of Arrival (UL-AoA) , and Multi-cell Round Trip Time (Multi-RTT) . Taking the DL-TDOA as an example, the UE 110 may measure arrival time of the PRSs from the base stations 120 and calculate DL-TDOA by for example subtracting the arrival time of the PRSs from the

neighbor base stations

120b, 120c from the arrival time of the PRS from the serving base station 120a. Here the serving base station 120a is regarded as a reference base station in the positioning procedure. The DL-TDOA measurement, also known as Reference Signal Time Difference (RSTD) measurement, may be sent in a PRS measurement report to the location server 130 where the DL-TDOA is converted into a distance difference between a first distance from the UE 110 to the serving base station 120a and a second distance from the UE 110 to the respective

neighbor base stations

120b, 120c. Since the location server 130 knows positions of the base stations 120 (or positions of physical antennas of the base stations) , the location server 130 can calculate a hyperbola from a distance difference between the serving base station and a neighbor base station, and an intersecting point of two or more such hyperbolas can be determined as a position of the UE 110. Here the DL-TDOA method is described as an example, and it would be appreciated that example embodiments discussed herein are not limited to the DL-TDOA positioning method.

To assist positioning operations in NR, the location server 130 and/or the base station 120 may provide positioning configurations to the UE 110 for DL or UL positioning procedure. For example, the positioning configuration involved in both DL and UL positioning may include capability and/or location information request used by the location server 130 to request the capability and/or location measurements of the UE 110 to support various positioning methods. In addition, the positioning configuration for DL positioning may include PRS configuration, measurement and report configuration, and/or other positioning assistance data applicable to the DL positioning method. For UL positioning, the positioning configuration may include SRS configuration (e.g., positioning SRS resource set list) , and positioning SRS activation or deactivation signaling. Hereinafter, for purpose of discussion, the positioning configuration for DL positioning is also referred to as positioning assistance data, while the positioning configuration for UL positioning is also referred to as SRS configuration.

In a 5G NR network, the UE 110 may be considered to be in different RRC modes or statuses relative to the network. Fig. 2 illustrates a UE RRC state machine and state transitions in NR. The UE 110 may have only one RRC status in NR at one time. As illustrated, the UE 110 can be in RRC_CONNECTED status, RRC_INACTIVE status, or RRC_IDLE status. When the UE 110 is in the RRC connected status, it can communicate with the base station 120 using the typical NR physical channels (e.g., a physical uplink shared channel (PUSCH) , a physical downlink shared channel (PDSCH) ) to perform data transmission or reception. In order to enable a low power consumption, the UE 110 may be transitioned to RRC_INACTIVE status or RRC_IDLE status. When the UE 110 is in the RRC_IDLE status, it is only monitoring the network for paging and system information. When the UE 110 is in the RRC_INACITIVE status, the UE 110’s RRC connection to the network is suspended and can be quickly resumed.

As illustrated in Fig. 2, the UE 110 may transition to the RRC_IDLE status from the RRC_CONNECTED status when the RRC connection is released by the base station 120. The UE 110 may transition from the RRC_IDLE status back to the RRC_CONNECTED status by establishing an RRC connection. In addition, from the RRC_CONNECTED status, the UE 110 may transition to the RRC_INACTIVE status when receiving an RRC release with suspend message from the base station 120. From the RRC_INACTIVE status, the UE 110 may transition back to the RRC_CONNECTED status by resuming the RRC connection.

As discussed above, in order to perform the positioning method, the UE 110 needs to receive positioning configuration from the location server 130 via the base station 120. Therefore, the UE 110 may need to update the positioning configuration in time. This poses problems when the UE 110 is in an RRC inactive or idle status. Until Rel. 16, the RRC idle or inactive status does not support any data transmission/reception. Therefore, the UE 110 has to establish or resume the RRC connection for any DL and UL data. Connection establishment and subsequently release to idle/inactive status happens for each data transmission however small and infrequent the data packets are. This means that, when a packet (e.g., the updating positioning configuration) arrives for the UE 110 in RRC idle or inactive status, as an example, the network will initiate the paging procedure for the UE 110, and then the UE 110 will start a random access (RA) procedure to establish or resume connection before data transfer. This would result in unnecessary power consumption and signaling overhead.

Although some basic functions for positioning UEs in RRC inactive status have been defined in Rel. 17, there are still certain problems need to be resolved to improve efficiency of positioning for UEs in the RRC inactive or idle status. For example, the positioning configuration may be different for RRC connected status and RRC inactive/idle status due to energy consumption constraints. Taking DL positioning as an example, it is expected for the UE 110 in RRC inactive/idle status to report positioning measurements less frequently than in RRC connected status. However, the location server 130 (e.g., an LMF) is not able to adjust positioning assistance data in time, since the UE 110’s RRC status may be invisible at the LMF. In addition, as positioning requirement (e.g., positioning quality of service (QoS) ) and positioning performance (e.g., latency) is unknown at the serving base station 120a, the serving base station 120a has no idea whether positioning configuration provided in RRC release or RRC suspend message is appropriate or not. If the configuration information is not appropriate, the location sever 130 or the UE 110 may trigger positioning configuration update after the UE 110 has transitioned to the RRC inactive/idle status. As described above, this additional positioning configuration update will trigger operations such as paging, random access, PDSCH reception, which lead to additional power consumption for the UE 110. This is clearly against the original intention of power saving in the RRC inactive/idle status.

Therefore, it is desirable to provide an efficient mechanism to update the positioning configuration for a terminal device to be used in an RRC inactive/idle status.

Hereinafter, example embodiments of methods and apparatuses supporting positioning configuration update would be described in detail with reference to the drawings. In the example embodiments, the positioning configuration update is implemented before the terminal device enters the RRC inactive or idle status. The network device may assist the location server to update the positioning configuration to be used for the terminal device in the RRC inactive or idle status. The example embodiments can support seamless positioning configuration update for UL and DL positioning in case of RRC status transition. There is no need to update the positioning configuration after the terminal device moves to the RRC inactive or idle status. Thus, low power consumption can be achieved at the terminal device, and signaling overhead and positioning latency can be reduced.

Fig. 3 is a high-level message flow diagram illustrating a positioning configuration update process according to an example embodiment. It would be appreciated that the positioning configuration update process may refer to a process to determine an initial positioning configuration to be used in an RRC inactive/idle status or a process to update the positioning configuration when the initial positioning configuration has been determined. The term “update” should be interpreted in a similar way throughout the present disclosure. The process shown in Fig. 3 may be performed by a base station, a location server and a user equipment. For example, the UE 110, the serving base station 120a and the location server 130 in the communication network 100 described above with reference to Fig. 1 may be configured to perform the positioning configuration update process. The UE 110, the serving base stations 120a and the location server 130 each may include a plurality of components, modules, means or elements to perform operations discussed below, and the components, modules, means and elements may be implemented in various manners including but not limited to for example software, hardware, firmware or any combination thereof to perform the operations.

Referring to Fig. 3, assuming the UE 110 is initially in a connected state with the serving base station 120a and the location server 130 (e.g. an LMF) . In some instances, the serving base station 120a may determine to trigger the UE 110 to enter RRC inactive or idle status for power consumption. At an operation 210, instead of sending the RRC release or RRC release with suspend message immediately, the serving base station 120a may decide to defer release of an RRC connection between the serving base station 120a and the UE 110. For example, the serving base station 120a may defer the RRC release or suspend indication to the UE 110 for a period of time to implement the positioning configuration update. When the time period expires, the UE 110 may transition to the RRC inactive or idle status.

Within the deferred time window, a proactive positioning configuration update procedure 220 can be performed before the UE 110 transitions to the RRC inactive or idle status. For example, the serving base station 120a may initiate the positioning configuration update when it determines that the previous positioning configuration is not appropriate for the RRC inactive or idle status or the UE 110 still needs to maintain the positioning session active. Alternatively, the base station 120a may directly trigger the positioning configuration update for the UE 110 so as to avoid updating the positioning configuration information after the UE 110 transitions to the inactive or idle status.

As illustrated in Fig. 3, the proactive positioning configuration update procedure can be performed by sending a request to the location server 130 at an operation 222. In an example embodiment, the base station 120a may send a request for positioning configuration update to the location server 130. Alternatively, the base station 120a may inform the UE 110 it would enter RRC inactive or idle status and indicates the UE 110 certain assisted information, such as a deferred timer indicating when to transition to RRC inactive/idle status, DRX configuration used for RRC inactive or idle status, cause for the defer, or the like. Then the UE 110 may decide to send a request for positioning configuration update to the base station 120a or the location server 130.

In an example embodiment, the request for positioning configuration update may include a request for positioning assistance data update for DL positioning, and/or a request for sounding reference signal (SRS) configuration update for UL positioning. As discussed above, the network may use a UL, DL, or UL-DL positioning method to position the UE 110. Depending on the used positioning method, the UE 110 or the base station 120a may send a respective request to the location server 130.

In an example embodiment, the request may include some information associated with the UE 110 and/or the positioning configuration update to facilitate the location server 130 to determine the positioning configuration update timely and appropriately. For example, the request may include at least one of cause for sending the request, suggestion for one or more parameters of the positioning configuration, a response timer before which the location server 130 needs to provide the positioning configuration update, and DRX configuration for the UE 110 to use in the RRC inactive or idle status.

In response to receiving the request, the location server 130 may determine the new positioning configuration to be used in RRC inactive or idle status at least based on the request information from the UE 110 or the base station 120a. Then, at an operation 224, the location server 130 may send the determined positioning configuration update to the UE 110, for example, before the response timer expires. Alternatively or additionally, in case where the positioning configuration update is for UL positioning, e.g., the reference signal is SRS for positioning purposes, it is better for the base station 120a to determine the SRS configuration. Thus, in an example embodiment, the location server 130 may determine and send a suggested SRS configuration to the base station 120a. Based on the received suggestion from the location server 130, the base station 120a may determine the SRS configuration update to be used for UL positioning, and send the SRS configuration update to the UE 110.

At an operation 230, the base station 120a may send an RRC release or release with suspend message to indicate the UE 110 to enter RRC inactive/idle status after the positioning configuration update has been determined or after the deferred timer expires. Then at 240, the UE 110 may switch to the RRC inactive or idle status when receiving the message. For example, if an RRC release message is received, the UE 110 may release the access stratum (AS) context and switch to RRC idle status. In case where an RRC release with suspend message is received, the UE 110 moves to RRC inactive status in which the AS context is maintained in the UE 110.

It would be understood that although the RRC release or release with suspend message is sent at the operation 230 after the proactive positioning configuration update procedure 220, the RRC release or release with suspend message may also be sent in another time. For example, when the base station 120a determines to defer the release of RRC connection at the operation 210, it may immediately indicate the UE 110 to release RRC connection and also configure a deferred timer to the UE 110. In this case, the UE 110 may also switch to the RRC inactive or idle status when it receives the positioning configuration update or the deferred timer expires.

Here Fig. 3 shows only a high-level process for the positioning configuration update, and details of the operations in the process will be discussed below.

Fig. 4 is schematic message flow diagram illustrating a positioning assistance data configuration update process for DL positioning according to an example embodiment of the present disclosure. The process shown in Fig. 4 may be performed by for example the UE 110, the serving base station 120a of the UE 110, and the location server 130.

In some cases, the serving base station 120a may determine to trigger the UE 110 to enter RRC inactive or idle status in order to reduce power consumption. The determination may be, for example, based on a buffer status for the UE 110. If the buffer status indicates that there is no or only small data transmission or reception at the UE 110 for a relatively long period, the serving base station 120a may make the decision to initiate a transition from RRC connected status to RRC inactive or idle status for the purpose of power saving.

Referring to Fig. 4, when the serving base station 120a determines to put the UE 110 into RRC inactive or idle status. At an operation 210, the base station 120a may decide to defer release of the RRC connection between the base station 120a and the UE 110. For example, the base station 120a would not immediately indicate the UE 110 to release RRC connection. Rather, the base station 120a may trigger a positioning configuration update procedure to update the positioning assistance data for the UE 110, which will be described in more detail below.

In an example embodiment, before the base station 120a triggers the positioning configuration update procedure, it may, at an operation 212, determine if the positioning configuration update for DL positioning is needed. For example, the determination may be based on capability and/or current positioning configuration of the UE 110. The capability information may include, but not limited to, at least one of device category, power status, and power saving mode of the UE 110, and information indicative of whether positioning service is involved. In an example, the UE 110 may report some of the capability information (e.g., device category, power status, and power saving mode) to the base station 120a in advance or in response to receiving a request from the base station 120a. Then, the base station 120a may make a determination if the positioning assistance data for DL positioning needs to be updated.

By way of example, the base station 120a may realize that the UE 110 not only needs to maintain the positioning session active in order to support a position based service, but also needs to save power if the remaining battery of the UE 110 is low or the UE 110 is a low power UE, such as an asset tracking device, a Low Power High Accuracy Positioning (LPHAP) UE, or the like, then the base station 120a may make the decision to trigger the positioning assistance data update.

In some example embodiments, the operation 212 may be omitted. In other words, the base station 120a may directly trigger the positioning assistance data update for the UE 110 so as to avoid updating the positioning configuration information after the UE 110 transitions to the inactive or idle status.

When the positioning assistance data update procedure is initiated, at an operation 214, the base station 120a may send an indication of a deferred timer to the UE 110. The indication may indicate that release of the RRC connection between the base station 120a and the UE 110 is deferred, and the UE 110 will transition to RRC inactive or idle status after the timer expires. In an example, the base station may send the indication of the deferred timer via RRC signaling, e.g., an RRC reconfiguration message. In this case, the base station 120a may also set a timer (e.g., equal to the deferred timer) to wait for a reply form the UE 110 which may indicate success reception or completion of the positioning assistance data update. When the base station 120a receives the reply or the timer expires, it may instruct the UE 110 to enter an RRC inactive or idle status. Alternatively, the indication of the deferred timer may be sent together with the RRC release or release with suspend message. In other words, the UE 110 may receive the indication of the deferred timer in the RRC release or release with suspend message. In response to the RRC message, the UE 110 will really release the RRC connection when the positioning assistance data is received or the deferred timer expires.

In an example embodiment, at the operation 214, the base station 120a may also inform the UE 110 of other assisted information together with the deferred timer indication via RRC signaling. For example, the assisted information may include an indication of cause for defer (e.g., positioning configuration update) , and/or discontinuous reception (DRX) configuration for the UE 110 to use in the RRC inactive or idle status. It would be understood that, the DRX configuration may be sent at other times or included in other messages. For example, the UE 110 may receive from the base station 120a the DRX configuration in the RRC release or release with suspend message.

As discussed above, there are two options for sending the request of positioning configuration update. In a first option, the base station 120a may be responsible for sending the request. In an example, at an operation 310a, the base station 120a may initiated a request to the location server 130 for the positioning assistance data update. For example, the base station 120a may send request to the location server 130 via NRPPa signaling.

The request may include various information associated with the positioning assistance data update. For example, the information may include at least the cause for sending the request (i.e., the RRC status transition of the UE 110) , the DRX configuration for the UE 110 to use in the RRC inactive or idle status, and a response timer that sets the time interval before which the location server 130 needs to provide the positioning assistance data update. The response timer may be determined according to the deferred timer that defines a duration by which release of an RRC connection between the UE 110 and the base station 120a is deferred, as discussed above. For example, the response timer may expire before the deferred timer.

The request information may further include suggestion for one or more parameters of the positioning assistance data update. By way of example, the location server 130 may consider the above DRX configuration when determining the DL PRS configuration and measurement report configuration, e.g., in order that the DL PRS reception period and the measurement period may be aligned with the on-duration period indicated by the DRX configuration for the power saving. As another example, power consumption may be taken into account to determine the positioning assistance data update. For example, it is preferable to configure a long measurement report period, so the frequency of the measurement report can be reduced.

As another option, the UE 110 may be responsible for sending the request of positioning assistance data update. For example, at an operation 310b, in response to receiving an indication (e.g., at 214) that it would enter the RRC inactive or idle status, and a deferred timer is set for the purpose of positioning assistance data update, the UE 110 may decide whether to trigger the request for positioning assistance data update. Similar to the operation 212, the UE 110 may make the decision based on capability and/or current positioning assistance data. The capability information may include, but not limited to, at least one of device category, power status, and power saving mode of the UE 110, and information indicative of whether positioning service is involved. The current positioning assistance data may include, but not limited to, current PRS configuration, measurement report configuration, and the like.

By way of example, if the UE 110 is a low power UE (e.g., an asset tracking device, or an LPHAP UE) , and it realizes that the remaining battery is low, a determination can be made to trigger the request for updating positioning assistance data. As another example, if most of the PRS configuration fall out of the DRX on-duration, the UE 110 may make the decision to trigger the positioning assistance data update.

When the request for positioning assistance data is triggered, at an operation 312b, the UE 110 may send the request to the location server 130, e.g., via LPP signaling. Alternatively, the UE 110 may send the request to the base station 120a via RRC signaling, then the base station 120a forwards the request to the location sever 130 via NRPPa signaling.

In an example, the request may include at least the cause for sending the request, the DRX configuration for the UE 110 to use in the RRC inactive or idle status, suggestions for one or more parameters of the positioning assistance data update, and a response timer before which the location server 130 needs to provide the positioning assistance data update. The details of the request information may be analogous to the description made with reference to the operation 310a, and a redundant description thereof is omitted here.

In response to receiving the request at

operation

310a or 312b, the location server 130 may, at an operation 320, determine the positioning assistance data update based at least on the request information received from the base station 120a or the UE 110. For example, the location server 130 may accept the suggestions from the base station 120a or the UE 110 to be the positioning assistance data update directly. In another example, the location server 130 may determine the positioning assistance data update on its own, using the request information, as well as other information such as positioning requirement (e.g., QoS) , positioning performance (e.g., positioning latency) . Then, at an operation 330, the location server 130 may send the determined positioning assistance data update to the UE 110, for example, before the response timer expires. The configuration update may be sent to the UE 110 via LPP signaling. Alternatively, the location server 130 may send the configuration update to the base station 120a via NRPPa signaling, then the base station 120a forwards the configuration update to the UE 110 via RRC signaling.

At an operation 340, the base station 120a may send an RRC release or release with suspend message to the UE 110. For example, when the UE 110 receive or complete the positioning assistance data update, it may send an indication indicative of the reception or completion of the positioning assistance data update to the base station 120a, for example, before the deferred timer expires. Then, the base station 120a may generate and send the RRC release or release with suspend message. On the other hand, when the deferred timer expires without reception of the indication, the base station 120a may also generate and send the RRC release or release with suspend message to the UE 110. At an operation 240, the UE 110 may switch from the RRC connected status to one of the RRC inactive or idle status when receiving the RRC release or release with suspend message.

Fig. 5 is a schematic message flow diagram illustrating an SRS configuration update process for UL positioning according to an example embodiment of the present disclosure. The process shown in Fig. 5 may be performed by for example the UE 110, the serving base station 120a of the UE 110, and the location server 130.

Referring to Fig. 5, at the beginning of the process, the serving base station 120a may decide to defer release of the RRC connection between the base station 120a and the UE 110 at the operation 210 so that an SRS configuration update procedure can be performed. This operation has been described above with respect to Fig. 4 and a reductant description is omitted here.

In an example embodiment, before the base station 120a triggers the SRS configuration update procedure, it may, at an operation 213, determine if the configuration update for UL positioning is needed. The determination may be based on capability and/or current positioning configuration of the UE 110. By way of example, if the base station 120a finds out that the UE 110 is a positioning UE (e.g., an LPHAP UE) , and the previous SRS configuration is not associated with the RRC inactive or idle status, it may be determined that the positioning configuration needs to be updated. As another example, the base station 120a may realize that the UE 110 not only needs to maintain the positioning session active, but also needs to save power if the remaining battery of the UE 110 is low or the UE 110 is a low power UE (e.g., asset tracking device) , then the base station 120a may make the decision to trigger the SRS configuration update.

When the SRS configuration update procedure is initiated, at an operation 214, the base station 120a may send an indication of a deferred timer to the UE 110. The indication may indicate that release of the RRC connection between the base station 120a and the UE 110 is deferred, and the UE 110 will transition to RRC inactive or idle status after the timer expires. In an example, the base station may send the indication of the deferred timer via RRC signaling, e.g., an RRC reconfiguration message. In this case, the base station 120a may also set a timer that is equal to the deferred timer, and before the timer expires, determine the SRS configuration update. When the configuration update is determined before the timer expires, the base station 120a may instruct the UE 110 to enter the RRC inactive or idle status. Alternatively, the indication of the deferred timer may be sent together with the RRC release or release with suspend message. In response to the RRC message, the UE 110 will really release the RRC connection when the SRS configuration is received or the deferred timer expires.

In an example embodiment, at the operation 214, the base station 120a may also inform the UE 110 of other assisted information together with the deferred timer indication. For example, the assisted information may include an indication of cause for defer, and/or discontinuous reception (DRX) configuration for the UE 110 to use in the RRC inactive or idle status.

Similar to the positioning assistance data update procedure as described with reference to Fig. 4, there are two options for sending the request of SRS configuration update. In a first option, the base station 120a may be responsible for sending the request. For example, at an operation 410a, the base station 120a may initiated a request to the location server 130 for the SRS configuration update. For example, the base station 120a may send the request to the location server 130 via NRPPa signaling.

The request may include various information associated with the SRS configuration update. For example, the information may include at least the cause for sending the request (i.e., the RRC status transition of the UE 110) , the DRX configuration for the UE 110 to use in the RRC inactive or idle status, and a response timer that sets the time interval before which the location server 130 needs to provide the SRS configuration update. The response timer may be determined according to the deferred timer discussed above with reference to operation 214. For example, the response timer may expire before the deferred timer.

The request information may further include suggestion for one or more parameters of the SRS configuration update. By way of example, the location server 130 may consider the above DRX configuration when determining the SRS configuration, e.g., in a way that the SRS transmission period may be aligned with the on-duration period indicated by the DRX configuration. As another example, it is preferable to configure reduced SRS transmission opportunities and/or resources (e.g., reduced transmission frequency, reduced bandwidth, and reduced subframe, etc. ) for the SRS configuration update, so the power consumption can be reduced.

In response to receiving the request, the location server 130 may determine a suggested SRS configuration for the UE 110, for example, based on the request information, as well as other information such as QoS requirement for the positioning service. Then, at an operation 412a, the location server 30 may send the determined suggested SRS configuration to the base station 120a via NRPPa signaling.

At an operation 414a, the base station 120a may determine the SRS configuration update based at least on the received suggested SRS configuration from the location server 130. In an example embodiment, the base station 120a may determine the SRS resources to be allocated for positioning the UE 110, and associated SRS configuration parameters by using the DRX configuration, and the suggested SRS configuration. For example, the determined SRS configuration update may be aligned with the DRX configuration for the purpose of power saving.

Then the base station 120a may send the determined SRS configuration update including the SRS resources and associated SRS configuration parameters to the UE 110 and the location server 130. For example, at an operation 416a, the base station 120a may send the SRS configuration update to the location server 130 through an Uplink Positioning Information Update message using NRPPa protocol.

As another option, the UE 110 may be responsible for sending the request of SRS configuration update. For example, at an operation 410b, in response to receiving an indication (e.g., at 214) that it would enter the RRC inactive or idle status, and a deferred timer is set for the purpose of SRS configuration update, the UE 110 may decide whether to trigger the request for SRS configuration update. Similar to the operation 213, the UE 110 may make the decision based on capability and/or current SRS configuration. The capability information may include, but not limited to, at least one of device category, power status, and power saving mode of the UE 110, and information indicative of whether positioning service is involved. The current SRS configuration may include, but not limited to, SRS configuration parameters, and the like.

By way of example, if the UE 110 is a low power UE (e.g., an asset tracking device, or an LPHAP UE) , and it realizes that the remaining battery is low, a determination can be made to trigger the request for updating SRS configuration. As another example, if most of the current SRS configuration fall out of the DRX on-duration, the UE 110 may make the decision to trigger the SRS configuration update.

When the request for SRS configuration update is triggered, at an operation 412b, the UE 110 may send the request to the location server 130, e.g., via LPP signaling. Alternatively, the UE 110 may send the request to the base station 120a via RRC signaling, then the base station 120a forwards the request to the location sever 130 via NRPPa signaling.

In response to receiving the request from the UE 110, the location server 130 may assist the base station 120a to determine the SRS configuration update for the UE 110. For example, through operations 414b, 416b, 418b, the location server 130 may determine and send a suggested SRS configuration to the base station 120a, which may then determine the SRS configuration update based at least on the suggested SRS configuration from the location server 130 and send the SRS configuration update to the location server 130. The operations 414b, 416b, 418b are analogous to operations 412a, 414a, 416a described above and a reductant description is omitted here.

As discussed above, the base station 120a may send the determined SRS configuration update to the UE 110. For example, at an operation 430, the SRS configuration update may be carried in an RRC release or release with suspend message indicating the UE 110 to enter the RRC inactive or idle status. On the other hand, when the deferred timer expires before the SRS configuration update is determined, the base station 120a may also generate and send the RRC release or release with suspend message to the UE 110. At an operation 240, the UE 110 may switch from the RRC connected status to one of the RRC inactive or idle status when receiving the RRC message.

Fig. 6 shows a flowchart of an example method 500 for positioning configuration update in accordance with an example embodiment of the present disclosure. The method 500 can be implemented at a terminal device e.g. the UE 110 discussed above. It would be understood that steps illustrated in dashed-line blocks represent optional steps and they can be omitted in some example embodiments. In some example embodiments, the method 500 may further include one or more steps that are performed at the UE 110 as described above with respect to Figs. 4-5. It would also be understood that details of some steps in the procedure 500 have been discussed above with respect to Figs. 4-5 and the procedure 500 will be described here in a simple manner.

At block 510, the terminal device may report capability of the terminal device to the network device. For example, the capability comprising at least one of device category, power status, and power saving mode of the terminal device.

At block 520, the terminal device may receive form the network device an indication of a deferred timer by which release of a radio resource control (RRC) connection between the terminal device and the network device is deferred. In some example embodiments, the indication of the deferred timer is received in an RRC release or release with suspend message. In some example embodiments, the indication of the deferred timer is received via RRC signaling.

At block 530, the terminal device may receive an indication of cause for defer and/or discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status from the network device. For example, the DRX configuration may be received together with the indication of the deferred timer via RRC signaling or in an RRC release or release with suspend message.

At block 540, the terminal device may decide to trigger the request for positioning configuration update based on capability and/or current positioning configuration of the terminal device, before sending the request for positioning configuration update.

At block 550, the terminal device may send to the network device or a location server, a request for positioning configuration update in response to the indication of the deferred timer. In some example embodiments, the request for positioning configuration update may comprise a request for positioning assistance data update for downlink positioning; and/or a request for sounding reference signal configuration update for uplink positioning. In some example embodiments, the request may include at least one of: cause for sending the request; suggestion for one or more parameters of the positioning configuration; a response timer before which the location server provides the positioning configuration update; and discontinuous reception (DRX) configuration for the terminal device to use in the RRC inactive or idle status.

At block 560, the terminal device may receive an RRC release or release with suspend message from the network device. For example, the terminal device may switch to the RRC inactive or idle status in response to the RRC release or release with suspend message.

At block 570, the terminal device may switch to an RRC inactive or idle status when the positioning configuration update or the RRC release or release with suspend message is received at the terminal device or the deferred timer expires.

Fig. 7 shows a flowchart of an example method 600 for positioning configuration update in accordance with an example embodiment of the present disclosure. The method 600 can be implemented at a network device e.g., the serving base station 120a discussed above. It would be understood that steps illustrated in dashed-line blocks represent optional steps and they can be omitted in some example embodiments. In some example embodiments, the method 600 may further include one or more steps that are performed at the base station 120a as described above with respect to Figs. 4-5. It would also be understood that details of some steps in the procedure 600 have been discussed above with respect to Figs. 4-5 and the procedure 600 will be described here in a simple manner.

At block 610, the network device may decide to defer release of a radio resource control (RRC) connection between the network device and a terminal device.

At block 620, the network device may send, to the terminal device, an indication of a deferred timer by which release of the RRC connection between the network device and the terminal device is deferred. In some example embodiments, the indication of the deferred timer is sent in an RRC release or release with suspend message. In some example embodiments, the indication of the deferred timer is sent via RRC signaling.

At block 630, the network device may send to the terminal device, an indication of cause for defer and/or discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status. For example, the DRX configuration may be sent together with the indication of the deferred timer via RRC signaling or in an RRC release or release with suspend message.

At block 640, the network device may determine if positioning configuration update is needed for the terminal device based on capability and/or current positioning configuration of the terminal device.

At block 650, the network device may send to a location server, a request of positioning configuration update for the terminal device. In some example embodiments, the request for positioning configuration update may comprise a request for positioning assistance data update for downlink positioning; and/or a request for sounding reference signal configuration update for uplink positioning. In some example embodiments, the request may include at least one of: cause for sending the request; suggestion for one or more parameters of the positioning configuration; a response timer before which the location server provides the positioning configuration update; and discontinuous reception (DRX) configuration for the terminal device to use in the RRC inactive or idle status.

At block 660, the network device may receive from the location server, a suggested sounding reference signal configuration for the terminal device.

At block 670, the network device may determine sounding reference signal configuration update for the terminal device at least partially based on the suggested sounding reference signal configuration.

At block 680, the network device may send, to the terminal device and the location server, the sounding reference signal configuration update for the terminal device.

At block 690, the network device may send an RRC release or release with suspend message to the terminal device when the deferred timer expires or when the network device has determined positioning configuration update for the terminal device.

Fig. 8 shows a flowchart of an example method 700 for positioning configuration update in accordance with an example embodiment of the present disclosure. The method 700 can be implemented at a location server e.g. the location server 130 discussed above. In some example embodiments, the method 700 may further include one or more steps that are performed at the location server 130 as described above with respect to Figs. 4-5. It would also be understood that details of some steps in the procedure 700 have been discussed above with respect to Figs. 4-5 and the procedure 700 will be described here in a simple manner.

At block 710, the location server may receive from a terminal device or a network device, a request of positioning configuration update for the terminal device, the request comprising a response timer.

In some example embodiments, the response timer expires before a deferred timer that defines a duration by which release of a radio resource control (RRC) connection between the terminal device and the network device is deferred.

In some example embodiments, the request may further includes at least one of: cause for sending the request, suggestion for one or more parameters of the positioning configuration, and discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status.

At block 720, the location server may send, to the terminal device or the network device, positioning configuration update for the terminal device before the response timer expires.

In some example embodiments, the request of positioning configuration update comprises a request of positioning assistance data update for downlink positioning, and the positioning configuration update comprises positioning assistance data update for the terminal device and is sent to the terminal device.

In some example embodiments, the request of positioning configuration update comprises a request of sounding reference signal (SRS) configuration update for uplink positioning, and the positioning configuration update comprises a suggested SRS configuration for the terminal device and is sent to the network device.

In some example embodiments, the method 700 may further receive, from the network device, an SRS configuration update for the terminal device to use in an RRC inactive or idle status.

Fig. 9 illustrates a block diagram of an example communication system 800 in which embodiments of the present disclosure can be implemented. As shown in Fig. 9, the communication system 800 may comprise a terminal device 810 which may be implemented as the UE 110 discussed above, a network device 820 which may be implemented as any one of the base stations 120 discussed above, and a network function node 830 which may be implemented as the location server 130 discussed above. In some example embodiments, alternatively, the location server 130 may be implemented as a component or part in the network device 820. Although Fig. 9 shows one network device 820, it would be appreciated that the communication system 800 may comprise a plurality of network devices 820 to position or assist positioning of the terminal device 810.

Referring to Fig. 9, the terminal device 810 may comprise one or more processors 811, one or more memories 812 and one or more transceivers 813 interconnected through one or more buses 814. The one or more buses 814 may be address, data, or control buses, and may include any interconnection mechanism such as series of lines on a motherboard or integrated circuit, fiber, optics or other optical communication equipment, and the like. Each of the one or more transceivers 813 may comprise a receiver and a transmitter, which are connected to one or more antennas 816. The terminal device 810 may wirelessly communicate with the network device 820 through the one or more antennas 816. The one or more memories 812 may include computer program code 815. The one or more memories 812 and the computer program code 815 may be configured to, when executed by the one or more processors 811, cause the terminal device 810 to perform operations and procedures relating to the UE 110 as described above.

The network device 820 may comprise one or more processors 821, one or more memories 822, one or more transceivers 823 and one or more network interfaces 827 interconnected through one or more buses 824. The one or more buses 824 may be address, data, or control buses, and may include any interconnection mechanism such as a series of lines on a motherboard or integrated circuit, fiber, optics or other optical communication equipment, and the like. Each of the one or more transceivers 823 may comprise a receiver and a transmitter, which are connected to one or more antennas 826. The network device 820 may operate as a base station for the terminal device 810 and wirelessly communicate with terminal device 810 through the one or more antennas 826. The one or more network interfaces 827 may provide wired or wireless communication links through which the network device 820 may communicate with other network devices, entities, elements or functions. The one or more memories 822 may include computer program code 825. The network device 820 may communicate with the network function node 830 via backhaul connections 828. The one or more memories 822 and the computer program code 825 may be configured to, when executed by the one or more processors 821, cause the network device 820 to perform operations and procedures relating to any one of the base stations 120.

The network function node 830 may comprise one or more processors 831, one or more memories 832, and one or more network interfaces 837 interconnected through one or more buses 834. The one or more buses 834 may be address, data, or control buses, and may include any interconnection mechanism such as a series of lines on a motherboard or integrated circuit, fiber, optics or other optical communication equipment, and the like. The network function node 830 may operate as a core network function node and wired or wirelessly communicate with the network device 820 through one or more links. The one or more network interfaces 837 may provide wired or wireless communication links through which the network function node 830 may communicate with other network devices, entities, elements or functions. The one or more memories 832 may include computer program code 835. The one or more memories 832 and the computer program code 835 may be configured to, when executed by the one or more processors 831, cause the network function node 830 to perform operations and procedures relating to the location server 130 as described above.

The one or

more processors

811, 821 and 831 discussed above may be of any appropriate type that is suitable for the local technical network, and may include one or more of general purpose processors, special purpose processor, microprocessors, a digital signal processor (DSP) , one or more processors in a processor based multi-core processor architecture, as well as dedicated processors such as those developed based on Field Programmable Gate Array (FPGA) and Application Specific Integrated Circuit (ASIC) . The one or

more processors

811, 821 and 831 may be configured to control other elements of the UE/network device/network element and operate in cooperation with them to implement the procedures discussed above.

The one or

more memories

812, 822 and 832 may include at least one storage medium in various forms, such as a volatile memory and/or a non-volatile memory. The volatile memory may include but not limited to for example a random access memory (RAM) or a cache. The non-volatile memory may include but not limited to for example a read only memory (ROM) , a hard disk, a flash memory, and the like. Further, the one or

more memories

812, 822 and 832 may include but not limited to an electric, a magnetic, an optical, an electromagnetic, an infrared, or a semiconductor system, apparatus, or device or any combination of the above.

It would be understood that blocks in the drawings may be implemented in various manners, including software, hardware, firmware, or any combination thereof. In some embodiments, one or more blocks may be implemented using software and/or firmware, for example, machine-executable instructions stored in the storage medium. In addition to or instead of machine-executable instructions, parts or all of the blocks in the drawings may be implemented, at least in part, by one or more hardware logic components. For example, and without limitation, illustrative types of hardware logic components that can be used include Field-Programmable Gate Arrays (FPGAs) , Application-Specific Integrated Circuits (ASICs) , Application-Specific Standard Products (ASSPs) , System-on-Chip systems (SOCs) , Complex Programmable Logic Devices (CPLDs) , etc.

Some exemplary embodiments further provide computer program code or instructions which, when executed by one or more processors, may cause a device or apparatus to perform the procedures described above. The computer program code for carrying out procedures of the exemplary embodiments may be written in any combination of one or more programming languages. The computer program code may be provided to one or more processors or controllers of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program code, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

Some exemplary embodiments further provide a computer program product or a computer readable medium having the computer program code or instructions stored therein. The computer readable medium may be any tangible medium that may contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but is not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

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

Although the subject matter has been described in a language that is specific to structural features and/or method actions, it is to be understood the subject matter defined in the appended claims is not limited to the specific features or actions described above. On the contrary, the above-described specific features and actions are disclosed as an example of implementing the claims.

Claims

A terminal device comprising:

at least one processor; and

at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processor, cause the terminal device at least to:

receive, from a network device, an indication of a deferred timer by which release of a radio resource control (RRC) connection between the terminal device and the network device is deferred;

send, to the network device or a location server, a request for positioning configuration update in response to the indication of the deferred timer; and

switch to an RRC inactive or idle status when the positioning configuration update is received at the terminal device or the deferred timer expires.
The terminal device of claim 1, wherein the request for positioning configuration update comprises:

a request for positioning assistance data update for downlink positioning; and/or

a request for sounding reference signal configuration update for uplink positioning.
The terminal device of claim 1, wherein the request includes at least one of:

cause for sending the request;

suggestion for one or more parameters of the positioning configuration;

a response timer before which the location server provides the positioning configuration update; and

discontinuous reception (DRX) configuration for the terminal device to use in the RRC inactive or idle status.
The terminal device of claim 1, wherein the indication of the deferred timer is received in an RRC release or release with suspend message.
The terminal device of claim 1, wherein the indication of the deferred timer is received via RRC signaling, and

the at least one memory and the computer program code are further configured to, with the at least one processor, cause the terminal device at least to receive an RRC release or release with suspend message from the network device, the terminal device switching to the RRC inactive or idle status in response to the RRC release or release with suspend message.
The terminal device of claim 1, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the terminal device at least to:

receive discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status from the network device, the DRX configuration being received together with the indication of the deferred timer via RRC signaling or in an RRC release or release with suspend message.
The terminal device of claim 1, wherein the indication of the deferred time is received together with an indication of cause for defer, and

the at least one memory and the computer program code are further configured to, with the at least one processor, cause the terminal device at least to decide to trigger the request for positioning configuration update based on capability and/or current positioning configuration of the terminal device, before sending the request for positioning configuration update.
The terminal device of claim 1, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the terminal device at least to:

report capability of the terminal device to the network device, the capability comprising at least one of device category, power status, and power saving mode of the terminal device.
A network device comprising:

at least one processor; and

at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processor, cause the network device at least to:

decide to defer release of a radio resource control (RRC) connection between the network device and a terminal device; and

send, to the terminal device, an indication of a deferred timer by which release of the RRC connection between the network device and the terminal device is deferred.
The network device of claim 9, wherein the indication of the deferred time is sent together with an indication of cause for defer, and

the at least one memory and the computer program code are further configured to, with the at least one processor, cause the network device at least to determine if positioning configuration update is needed for the terminal device based on capability and/or current positioning configuration of the terminal device.
The network device of claim 9, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the network device at least to:

send, to a location server, a request of positioning configuration update for the terminal device.
The network device of claim 11, wherein the request of positioning configuration update comprises:

a request for positioning assistance data update for downlink positioning; and/or

a request for sounding reference signal configuration update for uplink positioning.
The network device of claim 11, wherein the request includes at least one of:

cause for sending the request;

suggestion for one or more parameters of the positioning configuration;

a response timer before which the location server provides the positioning configuration update; and

discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status.
The network device of any one of claims 9-13, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the network device at least to:

receive, from the location server, a suggested sounding reference signal configuration for the terminal device;

determine sounding reference signal configuration update for the terminal device at least partially based on the suggested sounding reference signal configuration; and

send, to the terminal device and the location server, the sounding reference signal configuration update for the terminal device.
The network device of claim 9, wherein the indication of the deferred timer is sent in an RRC release or release with suspend message.
The network device of claim 9, wherein the indication of the deferred timer is sent via RRC signaling, and

the at least one memory and the computer program code are further configured to, with the at least one processor, cause the network device at least to send an RRC release or release with suspend message to the terminal device when the deferred timer expires or when the network device has determined positioning configuration update for the terminal device.
The network device of claim 9, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the network device at least to:

send, to the terminal device, discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status, the DRX configuration being sent together with the indication of the deferred timer via RRC signaling or in an RRC release or release with suspend message.
A location server comprising:

at least one processor; and

at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processor, cause the location server at least to:

receive, from a terminal device or a network device, a request of positioning configuration update for the terminal device, the request comprising a response timer; and

send, to the terminal device or the network device, positioning configuration update for the terminal device before the response timer expires.
The location server of claim 18, wherein the response timer expires before a deferred timer that defines a duration by which release of a radio resource control (RRC) connection between the terminal device and the network device is deferred.
The location server of claim 18, wherein the request of positioning configuration update comprises a request of positioning assistance data update for downlink positioning, and the positioning configuration update comprises positioning assistance data update for the terminal device and is sent to the terminal device.
The location server of claim 18, wherein the request of positioning configuration update comprises a request of sounding reference signal (SRS) configuration update for uplink positioning, and the positioning configuration update comprises a suggested SRS configuration for the terminal device and is sent to the network device.
The location server of claim 21, wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the location server at least to:

receive, from the network device, an SRS configuration update for the terminal device to use in an RRC inactive or idle status.
The location server of claim 18, wherein the request further includes at least one of:

cause for sending the request;

suggestion for one or more parameters of the positioning configuration; and

discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status.
A method implemented at a terminal device, comprising:

receiving, from a network device, an indication of a deferred timer by which release of a radio resource control (RRC) connection between the terminal device and the network device is deferred;

sending, to the network device or a location server, a request for positioning configuration update in response to the indication of the deferred timer; and

switching to an RRC inactive or idle status when the positioning configuration update is received at the terminal device or the deferred timer expires.
The method of claim 24, wherein the request for positioning configuration update comprises:

a request for positioning assistance data update for downlink positioning; and/or

a request for sounding reference signal configuration update for uplink positioning.
The method of claim 24, wherein the request includes at least one of:

cause for sending the request;

suggestion for one or more parameters of the positioning configuration;

a response timer before which the location server provides the positioning configuration update; and

discontinuous reception (DRX) configuration for the terminal device to use in the RRC inactive or idle status.
The method of claim 24, wherein the indication of the deferred timer is received in an RRC release or release with suspend message.
The method of claim 24, wherein the indication of the deferred timer is received via RRC signaling, and the method further comprises:

receiving an RRC release or release with suspend message from the network device, the terminal device switching to the RRC inactive or idle status in response to the RRC release or release with suspend message.
The method of claim 24, further comprising:

receiving discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status from the network device, the DRX configuration being received together with the indication of the deferred timer via RRC signaling or in an RRC release or release with suspend message.
The method of claim 24, wherein the indication of the deferred time is received together with an indication of cause for defer, and the method further comprises:

deciding to trigger the request for positioning configuration update based on capability and/or current positioning configuration of the terminal device, before sending the request for positioning configuration update.
The method of claim 24, further comprising:

reporting capability of the terminal device to the network device, the capability comprising at least one of device category, power status, and power saving mode of the terminal device.
A method implemented at a network device, comprising:

deciding to defer release of a radio resource control (RRC) connection between the network device and a terminal device; and

sending, to the terminal device, an indication of a deferred timer by which release of the RRC connection between the network device and the terminal device is deferred.
The method of claim 32, wherein the indication of the deferred time is sent together with an indication of cause for defer, and the method further comprises:

determining if positioning configuration update is needed for the terminal device based on capability and/or current positioning configuration of the terminal device.
The method of claim 32, further comprising:

sending, to a location server, a request of positioning configuration update for the terminal device.
The method of claim 34, wherein the request of positioning configuration update comprises:

a request for positioning assistance data update for downlink positioning; and/or

a request for sounding reference signal configuration update for uplink positioning.
The method of claim 34, wherein the request includes at least one of:

cause for sending the request;

suggestion for one or more parameters of the positioning configuration;

a response timer before which the location server provides the positioning configuration update; and

discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status.
The method of any one of claims 32-36, further comprising:

receiving, from the location server, a suggested sounding reference signal configuration for the terminal device;

determining sounding reference signal configuration update for the terminal device at least partially based on the suggested sounding reference signal configuration; and

sending, to the terminal device and the location server, the sounding reference signal configuration update for the terminal device.
The method of claim 32, wherein the indication of the deferred timer is sent in an RRC release or release with suspend message.
The method of claim 32, wherein the indication of the deferred timer is sent via RRC signaling, and the method further comprises:

sending an RRC release or release with suspend message to the terminal device when the deferred timer expires or when the network device has determined positioning configuration update for the terminal device.
The method of claim 32, further comprising:

sending, to the terminal device, discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status, the DRX configuration being sent together with the indication of the deferred timer via RRC signaling or in an RRC release or release with suspend message.
A method implemented at a location server, comprising:

receiving, from a terminal device or a network device, a request of positioning configuration update for the terminal device, the request comprising a response timer; and

sending, to the terminal device or the network device, positioning configuration update for the terminal device before the response timer expires.
The method of claim 41, wherein the response timer expires before a deferred timer that defines a duration by which release of a radio resource control (RRC) connection between the terminal device and the network device is deferred.
The method of claim 41, wherein the request of positioning configuration update comprises a request of positioning assistance data update for downlink positioning, and the positioning configuration update comprises positioning assistance data update for the terminal device and is sent to the terminal device.
The method of claim 41, wherein the request of positioning configuration update comprises a request of sounding reference signal (SRS) configuration update for uplink positioning, and the positioning configuration update comprises a suggested SRS configuration for the terminal device and is sent to the network device.
The method of claim 44, further comprising:

receiving, from the network device, an SRS configuration update for the terminal device to use in an RRC inactive or idle status.
The method of claim 41, wherein the request further includes at least one of:

cause for sending the request;

suggestion for one or more parameters of the positioning configuration; and

discontinuous reception (DRX) configuration for the terminal device to use in an RRC inactive or idle status.
An apparatus comprising:

means for receiving, from a network device, an indication of a deferred timer by which release of a radio resource control (RRC) connection between the terminal device and the network device is deferred;

means for sending, to the network device or a location server, a request for positioning configuration update in response to the indication of the deferred timer; and

means for switching to an RRC inactive or idle status when the positioning configuration update is received at the terminal device or the deferred timer expires.
An apparatus comprising:

means for deciding to defer release of a radio resource control (RRC) connection between the network device and a terminal device; and

means for sending, to the terminal device, an indication of a deferred timer by which release of the RRC connection between the network device and the terminal device is deferred.
An apparatus comprising:

means for receiving, from a terminal device or a network device, a request of positioning configuration update for the terminal device, the request comprising a response timer; and

means for sending, to the terminal device or the network device, positioning configuration update for the terminal device before the response timer expires.
A computer program product embodied in at least one non-transitory computer readable medium comprising program instructions for causing an apparatus at least to:

receive, from a network device, an indication of a deferred timer by which release of a radio resource control (RRC) connection between the terminal device and the network device is deferred;

send, to the network device or a location server, a request for positioning configuration update in response to the indication of the deferred timer; and

switch to an RRC inactive or idle status when the positioning configuration update is received at the terminal device or the deferred timer expires.
A computer program product embodied in at least one non-transitory computer readable medium comprising program instructions for causing an apparatus at least to:

decide to defer release of a radio resource control (RRC) connection between the network device and a terminal device; and

send, to the terminal device, an indication of a deferred timer by which release of the RRC connection between the network device and the terminal device is deferred.
A computer program product embodied in at least one non-transitory computer readable medium comprising program instructions for causing an apparatus at least to:

receive, from a terminal device or a network device, a request of positioning configuration update for the terminal device, the request comprising a response timer; and

send, to the terminal device or the network device, positioning configuration update for the terminal device before the response timer expires.