Sensing state transitions in a user equipment

Abstract

A user equipment (200a) and a network node (300), a corresponding method, computer program and computer program product for handling state transitions between sensing states in the UE are disclosed. The UE is operable in sensing states comprises a sensing active state and a sensing passive state. The method performed by the UE comprises performing, in conjunction with performing a state transition between the sensing active state and the sensing passive state, at least one operational task pertaining to a sensing service for the UE. The at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE, current sensing state of the UE, and to which one or more RRC states the current sensing state is mapped.

Description

[0001] SENSING STATE TRANSITIONS IN A USER EQUIPMENT

[0002] TECHNICAL FIELD

[0003] Embodiments presented herein relate to methods, a user equipment, a network node, computer programs, and a computer program product for handling state transitions between sensing states in the user equipment.

[0004] BACKGROUND

[0005] Some wireless communication networks provide sensing services in diverse application areas, such as detection, ranging and tracking of vulnerable road users, automated guided vehicles, or unmanned aerial vehicles. Different scenarios for sensing performed in third-generation partnership project (3GPP) wireless cellular communication networks using New Radio (NR) signals and protocols are schematically illustrated in Fig. 1. The suffix “-s” is short for “sensing” and indicates that the transmitted (Tx) and received (Rx) signals are for sensing rather than for communication purposes. The sensed object can be an active (connected) object or a passive (unconnected) object). Active objects are equipped with a radio transceiver and connected to the 3GPP network. A user equipment (UE) in connected state is an example of an active object from a sensing point-of-view. Passive objects are not connected to the 3GPP network during the sensing process. Such objects may lack a radio transceiver or may be powered off and thereby not communicating with the 3 GPP network.

[0006] In Fig. 1(a) is illustrated an example of monostatic sensing of an object, as represented by UE 200a, which can be a passive object or an active object, where a network node 300 transmits sensing signals (SS) that are reflected by UE 200a and the reflected sensing signal (SSr) is measured by the network node 300.

[0007] In Fig. 1(b) is illustrated an example of bi-static sensing of an object, as represented by UE 200a, where in one example a UE 200b transmits sensing signals that are reflected by object and the reflected sensing signal is measured by the network node 300b. In another example a network node 300 transmits sensing signals that are reflected by object and the reflected sensing signal is measured by UE 200b.

[0008] In Fig. 1(c) is illustrated an example of multi-static sensing of an object, as represented by UE 200a, where in one example a UE 200b transmits sensing signals that are reflected by UE 200a and the reflected sensing signals are measured by multiple receiving nodes e.g. by network node 300b and by UE 200c. In another example a network node 300a transmits sensing signals that are reflected by UE 200a and the reflected sensing signals are measured by multiple receiving nodes e.g. by network node 300b and by UE 200c.

[0009] Sensing can help to improve the position estimation of both active and passive objects. For active objects, whose positions are estimated using cellular signals sensing can be used as a means to make the position estimation more precise, while for passive objects sensing can either be the sole available scheme for determining its position, or sensing data can be fused by data provided by other sensors, such as inertial measurement unit (IMU), onboard light detection and ranging (LIDAR) device, etc.

[0010] In 3GPP networks, the operation and functionality of the radio resource control (RRC) layer are governed by the current state of the RRC in the UE and in the network node, such as RRC_Connected state, RRC_Idle state and RRC_Inactive state. In Fig. 2 is illustrated RRC state transitions in a NR-type 3GPP network.

[0011] Upon power up 410a, the UE 200a is de-registered 420 and enters the RRC disconnected, or idle, state 425. Upon the UE 200a being registered (and connected) 430, the UE 200 then enters the RRC connected state 432. The UE 200a could then either again enter the RRC disconnected, or idle, state 525 or the RRC connected inactive state 434. Further details relating to these state transitions will be disclosed next. Specifically, NR-type 3GPP network, in connected state, radio resources are allocated to the UE and active communication can take place between the UE and the 3GPP network. In idle state, the radio resources are released so as to enable other UEs to communicate with the 3GPP network. The inactive state is applicable for devices that require “always on” connectivity and save radio resources at the same time. In inactive state, radio resources are not reserved for the UE, but the UE can quickly come back to connected state due to the UE and the network node saving access stratum and security configuration information. The RRC states are not defined for a UE that is powered off. That is, when the UE is powered off, the UE does not have RRC state association. At power up, while the UE is de-registered, the UE resides in idle (disconnected) state, while when the UE is registered, the UE can be either in connected state or inactive state. The UE and the network node can transition from connected state directly to idle (disconnected) state, but the UE must transition to connected state by an attach and registration procedure before the UE can be in any of the connected or inactive states. The state transitions between these states and the functionality in each of these states are specified in 3GPP specifications. Different state transition procedures are defined during mobility procedures such as handover, Public Land Mobile Network (PLMN) selection, cell (re-)selection, etc.

[0012] Existing technologies for sensing services cannot handle RRC state transitions, for example when a sensed object is transitioning from an active state to a passive state. Specifically, when a UE is in connected state, the 3GPP network can use various positioning methods to determine the position of the UE and track the UE, for example downlink / uplink (DL / UL) time-of-arrival measurements or time-difference- of-arrival measurements (DL-TDOA), DL / UL angle-of-departure (AOD) measurements or angle-of-arrival (AOA) measurements or non-3GPP based measurements. The latter is since the UE can report such measurement data to the network (e.g., referring to Global Navigation Satellite System (GNSS) positioning, GNSS real-time kinematic (RTK) positioning, onboard sensor measurements, etc.). However, when the UE is in disconnected state (after Detach or RRC Release, see Fig. 2) or powered off, the UE is regarded as a passive object from a sensing point-of- view, and the above listed positioning and tracking schemes are not applicable.

[0013] 3GPP Technical Report 22.837 V2.0.0 discloses use cases and potential requirements for enhancement of the 5G system to provide sensing services addressing different target verticals / applications, e.g. autonomous / assisted driving, V2X, UAVs, 3D map reconstruction, smart city, smart home, factories, healthcare, maritime sector.

[0014] Also, in certain scenarios, the UE may be passive from a sensing point-of-view in any RRC state, including the connected and inactive states, due to not actively participating in localization procedures. However, some applications in the UE might still require that the UE is sensed and tracked as a passive object.

[0015] One issue with existing technologies is that when the UE is transitioning from an active sensing state to a passive sensing state, existing technology does not provide a seamless positioning and tracking service. In several mission critical (MC) and safety-critical scenarios, losing track of a UE is an issue, since the 3GPP network cannot provide position information to applications that rely on accurate position or velocity information of objects.

[0016] SUMMARY

[0017] An object of embodiments herein is to address the above issues.

[0018] A particular object is to enable continuous tracking of a UE, even if the UE at least temporarily appears as a passive object from a sensing point-of-view.

[0019] A particular object is to enable the network node to keep track of sensing state transitions at the UE and thereby to keep track of the position of the UE even when the UE changes sensing state from sensing active to sensing passive

[0020] According to a first aspect there is presented a method for handling state transitions between sensing states in a UE. The UE is operable in sensing states comprises a sensing active state and a sensing passive state. The method is performed by the UE. The method comprises performing, in conjunction with performing a state transition between the sensing active state and the sensing passive state, at least one operational task pertaining to a sensing service for the UE. The at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE, current sensing state of the UE, and to which one or more RRC states the current sensing state is mapped.

[0021] According to a second aspect there is presented a UE for handling state transitions between sensing states in the UE. The UE is operable in sensing states comprises a sensing active state and a sensing passive state. The UE comprises processing circuitry. The processing circuitry is configured to cause the UE to perform, in conjunction with performing a state transition between the sensing active state and the sensing passive state, at least one operational task pertaining to a sensing service for the UE. The at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE, current sensing state of the UE, and to which one or more RRC states the current sensing state is mapped. According to a third aspect there is presented a UE for handling state transitions between sensing states in the UE. The UE is operable in sensing states comprises a sensing active state and a sensing passive state. The UE comprises a perform module configured to perform, in conjunction with performing a state transition between the sensing active state and the sensing passive state, at least one operational task pertaining to a sensing service for the UE. The at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE, current sensing state of the UE, and to which one or more RRC states the current sensing state is mapped.

[0022] According to a fourth aspect there is presented a computer program for handling state transitions between sensing states in a UE. The UE is operable in sensing states comprises a sensing active state and a sensing passive state. The computer program comprises computer code which, when run on processing circuitry of a UE, causes the UE to perform actions. One action comprises the UE to perform, in conjunction with performing a state transition between the sensing active state and the sensing passive state, at least one operational task pertaining to a sensing service for the UE. The at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE, current sensing state of the UE, and to which one or more RRC states the current sensing state is mapped.

[0023] According to a fifth aspect there is presented a method for handling state transitions between sensing states in a UE. The UE is operable in sensing states comprises a sensing active state and a sensing passive state. The method is performed by a network node. The method comprises performing, in conjunction with obtaining an indication that that the UE is performing a state transition between the sensing active state and the sensing passive state, at least one operational task pertaining to a sensing service for the UE. The at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE.

[0024] According to a sixth aspect there is presented a network node for handling state transitions between sensing states in a UE. The UE is operable in sensing states comprises a sensing active state and a sensing passive state. The network node comprises processing circuitry. The processing circuitry is configured to cause the network node to perform, in conjunction with obtaining an indication that that the UE is performing a state transition between the sensing active state and the sensing passive state, at least one operational task pertaining to a sensing service for the UE. The at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE.

[0025] According to a seventh aspect there is presented a network node for handling state transitions between sensing states in a UE. The UE is operable in sensing states comprises a sensing active state and a sensing passive state. The network node comprises a perform module configured to perform, in conjunction with obtaining an indication that that the UE is performing a state transition between the sensing active state and the sensing passive state, at least one operational task pertaining to a sensing service for the UE. The at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE.

[0026] According to an eighth aspect there is presented a computer program for handling state transitions between sensing states in a UE. The UE is operable in sensing states comprises a sensing active state and a sensing passive state. The computer program comprises computer code which, when run on processing circuitry of a network node, causes the network node to perform actions. One action comprises the network node to perform, in conjunction with obtaining an indication that that the UE is performing a state transition between the sensing active state and the sensing passive state, at least one operational task pertaining to a sensing service for the UE. The at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE.

[0027] According to a ninth aspect there is presented a computer program product comprising a computer program according to at least one of the fourth aspect and the eighth aspect and a computer readable storage medium on which the computer program is stored. The computer readable storage medium could be a non-transitory computer readable storage medium. Advantageously, these aspects enable tracking of the UE, even if the UE at least temporarily appears as a passive object from a sensing point-of-view.

[0028] Advantageously, these aspects enable the network node to keep track of sensing state transitions at the UE and thereby to keep track of the position of the UE even when the UE changes sensing state from sensing active to sensing passive.

[0029] Advantageously, these aspects enable the network node to control when and how a state transition from sending active to sensing passive should take place. This is useful for a variety of applications that critically rely on continuously positioning and tracking of both active and passive objects.

[0030] Advantageously, these aspects enable the network node to continue sensing and tracking the UE when the UE becomes passive, irrespectively of RRC state change. That is, these aspects are applicable when sensing state transition is caused by RRC change or powering off when sensing state change is due to some other action (e.g., human interaction or application layer request).

[0031] Other objectives, features and advantages of the enclosed embodiments will be apparent from the following detailed disclosure, from the attached dependent claims as well as from the drawings.

[0032] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a / an / the element, apparatus, component, means, module, step, etc." are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, module, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.

[0033] BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The inventive concept is now described, by way of example, with reference to the accompanying drawings, in which:

[0035] Fig. 1 is a schematic diagram illustrating positioning and tracking of a UE according to embodiments; Fig. 2 is a schematic illustration of RRC states according to an example;

[0036] Fig. 3 is a schematic illustration of positioning and tracking of a UE according to embodiments;

[0037] Figs. 4 and 5 are flowcharts of methods according to embodiments;

[0038] Figs. 6 and 7 are signaling diagrams of methods according to embodiments;

[0039] Fig. 8 is a schematic diagram showing functional units of a UE according to an embodiment;

[0040] Fig. 9 is a schematic diagram showing functional modules of a UE according to an embodiment;

[0041] Fig. 10 is a schematic diagram showing functional units of a network node according to an embodiment;

[0042] Fig. 11 is a schematic diagram showing functional modules of a network node according to an embodiment; and

[0043] Fig. 12 shows one example of a computer program product comprising computer readable means according to an embodiment.

[0044] Fig. 13 shows an example of a communication system 1300 in accordance with some embodiments.

[0045] Fig. 14 shows a communication diagram of a host 1402 communicating via a network node 1404 with a UE 1406 over a partially wireless connection in accordance with some embodiments.

[0046] DETAILED DESCRIPTION

[0047] The inventive concept will now be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments of the inventive concept are shown. This inventive concept may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. Like numbers refer to like elements throughout the description. Any step or feature illustrated by dashed lines should be regarded as optional.

[0048] The embodiments disclosed herein relate to techniques for handling state transitions between sensing states in a UE 200a. In order to obtain such techniques there is provided a UE 200a, a method performed by the UE 200a, a computer program product comprising code, for example in the form of a computer program, that when run on processing circuitry of the UE 200a, causes the UE 200a to perform the method. In order to obtain such techniques there is further provided a network node 300, a method performed by the network node 300, and a computer program product comprising code, for example in the form of a computer program, that when run on processing circuitry of the network node 300, causes the network node 300 to perform the method.

[0049] In some examples, a UE, which is in a sensing active (SA) state determines, based on one or more rules, that the UE is to transition from the SA state to a sensing passive (SP) state, performs one or more operational tasks before entering the SP state. Nonlimiting examples of theses operational tasks are: completing ongoing sensing measurements, informing the network node about the imminent sensing state transition, informing the network node about the current UE mobility state e.g., UE velocity, UE location, UE direction of motion etc.

[0050] In some examples, the UE 200a is configured to operate on sensing signals in the SA state but not in the SP state. In some examples, operating on the sensing signals comprises any, or any combination, of: transmitting the sensing signals, receiving the sensing signals, processing the sensing signals.

[0051] In some examples, the UE determines whether the UE should be sensed (e.g., by another UE 200b or the network node) while the UE is in the SP state and might therefore inform the network node regarding how the UE should be sensed while the UE is in the SP state.

[0052] In some examples, the UE autonomously determines the transition from the SA state to the SP state based on evaluating if the UE meets one or more conditions related to the SP state. In some examples, the UE and the network node jointly determine when a state transition from the SA state to the SP state is imminent to be performed and / or it should be performed. Based on this information, the UE assists the network node to keep track of the mobility state (e.g., position, velocity, acceleration, direction of motion etc.) of the UE as well as other sensed characteristics, when the UE becomes passive from a sensing point-of-view. This can be achieved by the UE and the network node continuously maintaining sensing context information that allows the UE and the network node to determine (i) when and how the UE should execute a sensing state change, and (2) what information should be exchanged between the UE and the NW during the sensing state transition. Examples of sensing context information will be provided below.

[0053] In some examples, the UE determines, based on one or more rules, that the UE is going to transition from the SP state to the SA state, transitions to the SA state and performs one or more operational tasks after entering the SA state. Non-limiting examples of theses operational tasks are: starting performing sensing measurements within certain time period, informing the network node that the UE has changed its sensing state to the SA state, informing the network node whether the UE can participate in the sensing procedure (e.g., can transmit and / or receive sensing signals) in the SA state, etc.

[0054] In some examples, the UE assists the network node to obtain the initial position of the UE for active sensing when the UE is transitioning from the SP state to the SA state by sending its sensing context information to the network node. Sending the sensing context information can be event triggered or periodic, including a trigger by a human user of the UE or an application program run in the UE. The UE in the SA state can operate (e.g., transmit and / or receive) sensing signals (SS; e.g., radar signals) while in the SP state the UE does not operate any SS.

[0055] Sensing context information is thus maintained at the UE and the network node. The sending context information holds information about the UEs sensing service status. Such sensing service status information might specify whether the UE needs / request to be positioned and / or tracked, whether the UE is expected to change sensing state, the currently available position and velocity of the UE, battery status and other UE capability information, and / or currently used positioning and tracking method (e.g., DL-TDOA, UL-AOA, RTK, etc.). Further, the UE might maintain and provide information about its size, material properties (e.g., reflection coefficient), that are useful for sensing purposes when the UE becomes passive from a sensing point-of- view.

[0056] The sensing context information can be exchanged between the UE and the network node when the UE is attaching to the network, when the UE is in RRC connected state, and / or when the UE is transitioning from RRC connected state to RRC inactive or RRC idle state (e.g., as part of RRC release). The network node can use the sensing context information when the UE is transitioning from the SA state to the SP state and vice versa. The network node can update the sensing context information when the UE transitions from the SP state to the SA state. Likewise, the UE can update the sensing context information as soon as the UE enters the RRC connected state. Further, sensing context information can be changed between the UE and the network node by a deliberate human user action requesting that the UE participates in active sensing but wishes the UE to be sensed as a passive object.

[0057] In some non-limiting examples, the sensing context information pertains to any, or any combination, of: indication of positioning and / or tracking of the UE 200a, indication of a change of sensing state, position and / or velocity of the UE 200a, positioning and / or tracking method supported by the UE 200a, UE capability information.

[0058] In some non-limiting examples, the sensing context information pertains to any, or any combination, of: size of the UE 200a, surface material properties of the UE 200a.

[0059] In some non-limiting examples, the sensing context information pertains to any, or any combination, of: identification of any UEs 200b in proximity of the UE 200a, information how the UE 200a has acquired the identification of any UEs 200b in proximity of the UE 200a.

[0060] In some non-limiting examples, the sensing context information further pertains to any, or any combination, of: security information of the UE 200a, such as an encryption key, or an identifier of the encryption key. Further examples of sensing context information and examples where different examples of the sensing context information is used will be disclosed below.

[0061] In Fig. 3 is illustrated an example of how the positioning and tracking of a UE 200a initially in the SA state can be maintained after an RRC state transition from RRC connected state to RRC idle state, causing a state transition to the SP state. Initially, in Fig. 3(a), the UE 200a is in the SA state and the RRC connected state. From a sensing point-of-view, the UE 200a therefore appears as an active object. Downlink positioning reference signals as transmitted from the network node 300 can then be measured on by the UE 200a, and the UE 200a can report the measurements back to the network node 300 in a positioning report. The UE position as well as sensing data can then be reported from the network node 300 to the core network 510. In this case the network node 300 may or may not configure another UE 200b to transmit a sensing signal for sensing the UE 200a whose position is tracked. A change of RRC state to the RRC idle state causes a state transition to the SP state. From a sensing point-of-view, the UE 200a therefore in Fig. 1(b) appears as a passive object. As a consequence, the UE 200a is no longer capable on measuring on any downlink positioning reference signals. In order to track the position of the UE 200a, the network node 300 therefore configures the other UE 200b to transmit a sensing signal for sensing the UE 200a whose position is tracked. This enables the network node 300 to report the object position (corresponding to the UE position) as well as sensing data for the UE 200a to the core network 510.

[0062] As above, the UE is configured to operate in one of the two sensing states (SA and SP) at a time from the sensing point-of-view. In the SA state the UE can operate SS while in the SP state the UE cannot operate on any SS. The term operating the SS or operation of the SS refers to the UE transmitting the SS for the purpose of sensing and / or the UE receiving the SS from another device (e.g., network node, another UE 200b etc.) for the purpose of sensing. Therefore, in the SA state the UE, by the virtue of operating the SS, can actively participate in the sensing procedure for sensing another device or object and / or for enabling another device (e.g., a network node, another UE 200b, etc.) to sense the UE itself. On the other hand, the UE in the SP state cannot participate in any type of the sensing procedure. However, the UE can still be sensed by another device (e.g., a network node, another UE 200b) when the UE is the SP state. There can be different variants, or operational scenarios (OS), of the sensing states. The variants, or OS, of the sensing states may or may not be related to, or depend on, the UE RRC states. Examples of the variants, or OS, related to the sensing states are provided next.

[0063] In a first exemplary operational scenario (OS #1), the UE can be in the SA state only when the UE is in any of the RRC states e.g., in RRC connected state, RRC inactive state or RRC idle state. Otherwise, the UE is considered to be in the SP state e.g., when the UE is detached / disconnected (e.g., powered off, in flight mode etc.). That is, in some examples, the SA state is mapped to the UE 200a being in any of the RRC states: disconnected / idle, RRC connected, RRC connected inactive, and the SP state is mapped to the UE 200a being powered off.

[0064] In a second exemplary operational scenario (OS #2), the UE can be in the SA state only when the UE is in a particular RRC state e.g., in a high activity RRC connected state or in a low activity RRC state, i.e., in any of the states RRC connected and RRC connected inactive. Otherwise, the UE is considered to be in the SP state. In one example, the UE is in an SA state provided that the UE is in a high activity RRC state; otherwise, the UE is in an SP state (i.e., if it is in low activity RRC state or is detached). That is, in some examples, the SA state is mapped to the UE 200a being in any of the RRC states: RRC connected, RRC connected inactive, and the SP state is mapped to the UE 200a being in the RRC state disconnected / idle or the UE 200a being powered off.

[0065] In a third exemplary operational scenario (OS #3), the UE can be in the SA state only when the UE is in a single one of the RRC state. The UE can be in the SP state regardless of whether the UE is in RRC state or not in any of the RRC state. That is, in some examples, the SA state is mapped to the UE 200a being in one of the RRC states: disconnected / idle, RRC connected, RRC connected inactive, and the SP state is mapped to the UE 200a being in any RRC state except this one of the RRC states or the UE 200a being powered off.

[0066] The UE may support one or multiple OS related to the sensing states depending on the UE capability, etc. Therefore, the UE can be configured to operate according to a certain OS provided that the UE supports that OS. Even a UE supporting multiple OS may still indicate via signaling message to a network node a preference for a certain OS in which the UE prefers to operate at certain time. The network node may also configure the UE via signaling message to operate in one of the OS supported by the UE.

[0067] When operating in OS #1 or in OS #2, the UE may or may not be configured to perform positioning measurements on positioning signals (e.g., PRS, SRS, GNSS etc.) when the UE is in any of the RRC states. This gives rise to two broad scenarios. This is described in the below examples.

[0068] In one example related to OS #1 and OS #2, consider a UE in RRC connected state or in RRC inactive state, that is configured with positioning measurements. For example, the position of the UE can be determined and tracked according to 3GPP procedures, since in the RRC connected and / or in inactive state, the UE can process the DL positioning reference signal (PRS) and / or the UL sounding reference signal (PRS) for performing one or more positioning measurements. For example, the UE can perform downlink time-of-arrival (DL-TOA) measurement or downlink time- difference-arrival (DL-TDOA) measurements (relative to a reference TOA measurement), PRS reference signal strength (PRS-RSRP), UE Rx-Tx time difference measurements, etc. The UE can also determine its own position by measuring GNSS and GNSS RTK signals or use hybrid positioning methods and report the positioning measurement results and / or its determined location to the network node (e.g., a location server) via the Long-Term Evolution (LTE) Positioning Protocol (LPP), which in turn may be transmitted using a physical uplink shared channel (PUSCH) and uplink radio bearers. Such a positioning report compiled by the UE may include information about the UE’s mobility state (e.g., velocity, direction of motion, etc.) and multiple positioning information over a predefined period of time, where each estimated position is associated with a timestamp. In addition to using downlink signals analyzed by the UE to determine its own position and mobility state (e.g., velocity, direction of motion, etc.), the network node may also use uplink TDOA and uplink AOA methods to refine the UE’s position and UE’s mobility state (e.g., velocity, direction of motion, etc.). For example, in any of these RRC states (e.g., RRC connected state or in RRC inactive state), the UE transmitted positioning related signals such as sounding reference signals (SRS) can be used by a network node (e.g., a serving base station of the UE) to perform network node positioning measurements e.g., gNB Rx-Tx time difference, uplink time of arrival of signals (UL RTOA), SRS- RSRP (reference signal received power), zenith AOA and / or azimuth AOA measurements etc.

[0069] When the position of the UE is determined using cellular signals and UE reporting over uplink radio bearers, the network node may also use sensing to further improve the position estimation. In one example, the UE may further be configured by the network node to, in the SA state, operate (e.g., receive and / or transmit) sensing signals to improve the position estimation of the UE. For example, in this case the UE may perform measurements on the sensing signals and send the measurements to the network node and / or the UE transmitted sensing signals are measured by the network node (e.g., the serving base station) or by another UE 200b to estimate the position of the UE. These sensing measurement results can be combined with the positioning measurements to improve the positioning determination of the UE. In another example, the network node may configure another UE 200b to transmit a sensing (radar) signal that is reflected and used by the network node to determine the Doppler spread caused by the UE for which the position is tracked, and thereby to estimate the mobility state, e.g., velocity, of the tracked UE.

[0070] The UE may perform RRC Suspend or RRC release procedures or it may power off either purposely or due to running out of battery or leaving the coverage area, etc. In another example, the UE may also intentionally decide not to transmit and / or receive sensing signals while still being in one of the RRC states e.g., in RRC connected state, inactive state or in idle state. When the UE leaves the RRC states (not in e.g., connected, inactive state etc.), the UE becomes passive from a sensing point-of-view, since the UE has no longer radio resources and cannot measure downlink signals, including the downlink PRS. In this case, the network node may configure another UE 200b to form and transmit appropriate sensing signals that can be used for bistatic sensing. Alternatively, the network node may also use mono-static sensing to detect, position and track the UE when the UE is in the SP state.

[0071] In some examples related to OS # i and OS #2 above, the UE is configured to, in the RRC connected state or in the RRC inactive state, not perform any positioning measurements. For example, this maybe because either the UE does not support positioning measurements and / or the network node does not support or process the positioning related signals e.g., PRS, SRS, etc. Yet another reason can be that currently the network node does not intend to operate positioning related signals for the UE e.g., due to high traffic load, to save power, etc. In this case the UE cannot determine its position using the positioning measurement procedures. The UE may however be configured to operate the SS when in the SA state. The UE performs the measurements on the SS received by the UE and / or by another UE 200b on the SS transmitted by the UE and / or by the network node (e.g., the serving base station) on the SS transmitted by the UE. These measurement results are used for determining and tracking the UE mobility state.

[0072] Reference is now made to Fig. 4 illustrating a method for handling state transitions between sensing states in a UE 200a as performed by the UE 200a according to an embodiment. As noted above, the UE 200a is operable in sensing states comprising a sensing active (SA) state and a sensing passive (SP) state.

[0073] S106: The UE 200a performs, in conjunction with performing a state transition between the SA state and the SP state, at least one operational task pertaining to a sensing service for the UE 200a. The at least one operational task is, from a set of operational tasks, selected according to: sensing context information that holds information about a sensing service status of the UE 200a, current sensing state of the UE 200a, and to which one or more RRC states the current sensing state is mapped.

[0074] Embodiments relating to further details of handling state transitions between sensing states in the UE 200a as performed by the UE 200a will now be disclosed with continued reference to Fig. 4.

[0075] Some examples of operational tasks have already been provided and further examples of operational tasks will be provided below. In this respect, the at least one operational task might comprise the UE 200a transmitting the sensing context information to the network node 300.

[0076] Examples of different operational scenarios, also referred to as mappings between sensing states and RRC states, have been disclosed above. In some aspects, the UE 200a indicates via some signaling message to the network node 300 a preference for a certain operational scenario, or mapping, according to which the UE 200a prefers to operate at a certain time. Hence, in some embodiments, the UE 200a is configured to perform (optional) action S102.

[0077] S102: The UE 200a indicates, to the network node 300, preference for a mapping between the sensing states and the RRC states.

[0078] In some aspects, the network node 300 configures the UE 200a via some signaling message to operate in one of the operational scenarios, or mappings, supported by the UE 200a. Hence, in some embodiments, the UE 200a is configured to perform (optional) action S104.

[0079] S104: The UE 200a receives, from the network node 300, information of which of the sensing states are mapped to which of the RRC states.

[0080] There could be different ways in which the UE 200a could determine that it is going to transition between the sensing states. In some aspects, the UE 200a determines that it is going to transition between sensing states based on a rule, which depends on the operational scenario in which the UE 200a is configured. Hence, in some embodiments, that the UE 200a is to perform the state transition between the SA state and the SP state is determined based on a rule that depends on which of the sensing states are mapped to which of the RRC states. In some aspects, the UE 200a determines that it is going to transition between sensing states either autonomously, based on a message received from the network node 300 while UE 200a was in the SA state, based on some pre-configuration, based on execution of an application program, etc. Hence, in some embodiments, that the UE 200a is to perform the state transition between the SA state and the SP state is determined autonomously, based on information received from a network node 300, based on configuration, or based on execution of an application program in the UE 200a.

[0081] Embodiments as performed by the UE 200a where the state transition is performed from the SA state to the SP state will be disclosed next.

[0082] It is here assumed that the UE as operating in the SA state determines, or is instructed, that the UE is to transition to the SP state and that the UE performs one or more operational tasks before transitioning to the SP state. Hence, in some embodiments, the at least one operational task is performed before the state transition is performed. The UE can determine that it is going to transition to the SP state based on a rule, which depends on the operational scenario (e.g., OS #1, OS #2 or OS #3) for which the UE is configured. The UE can determine that it is going to transition to the SP state autonomously and / or based on a message received from the network node and / or based on pre-configuration (e.g., such as by retrieving information from the Subscriber Identity Module (SIM), or by an application program etc.). This is described next with examples.

[0083] In one example, a UE configured in OS #1 or in OS #2 can autonomously determine when the UE is going to transition to the SP state. This is because the rule defines the conditions under which the UE operates in different sensing states. For example, if a UE configured in OS #1 is going to be disconnected immediately, then the UE can determine that it will soon change its sensing state from the SA state to the SP state.

[0084] In another example, a UE configured in OS #3 can autonomously determine when the UE is going to transition to the SP state. For example, a user intentionally inactivating the active sensing may prevent the UE from transmitting and / or receiving the SS. In this case, from the sensing point-of-view the UE is going to change its sensing state to the PS state.

[0085] In another example, a UE configured in OS #3 can determine based on a message received from a network node that the UE is going to transition to the SP state. The message may further indicate timing information related to a reference time (Tr) from when the UE should transition to the SP state. The Tr can be an absolute time, such as Coordinated Universal Time (UTC), cell or system time such as System Frame Number (SFN) number, subframe number, etc.

[0086] Examples of one or more operational tasks which the UE may perform before entering into the SP state are provided next.

[0087] One operational task concerns completing any ongoing measurements related to the sensing service (e.g., measurements on the sensing signal and / or positioning related signals, etc. before the UE enters into the SP state.

[0088] One operational task concerns completing any transmissions of sensing signals related to the sensing service to a network node 300 before the UE enters the SP state. For example, the UE may transmit all the sensing signals during a sensing transmission resource e.g., during some given number of time resources.

[0089] One operational task concerns informing the network node 300 of the imminent sensing state transition. In this the respect the UE might send a message including sensing context information to the network node before the UE enters the SP state.

[0090] One operational task concerns determining whether or not the UE 200a is to be sensed in the PS state, and informing the network node 300 accordingly.

[0091] One operational task concerns postponing transitioning from the SA state to the PS state.

[0092] Non-limiting examples of the sensing context information for the present embodiment are provided next.

[0093] One example of sensing context information is information related to the results of one or more measurements related to the sensing procedure.

[0094] One example of sensing context information is information related to the current mobility state of the UE, e.g., UE current location, UE current velocity, UE current direction of motion, etc.

[0095] One example of sensing context information is information that the UE is going to transition to the SP state. This information may further comprise timing information about the time (e.g., UTC time, cell or system time, etc.) as to when the UE will start the state transition to the SP state.

[0096] One example of sensing context information is information of one or more reasons for the UE transitioning to the SP state, e.g., based on meeting one or more predefined conditions related to the OS in which the UE is configured, triggered by the UE itself, that UE battery power is below some threshold value, etc.

[0097] One example of sensing context information is information of whether the UE intends to continue to be sensed while in the SP state.

[0098] One example of sensing context information is information of whether the UE will revert to, or resume, the SA state. This information may further comprise timing information about the time (e.g., UTC time, cell or system time, etc.) as to when the UE will start the state transition back to the SA state.

[0099] In any of the above exemplary operational tasks, the UE may further postpone the transitioning from the SA state to the SP state until at least the operational task is completed by the UE. The maximum time period over which the transition can be postponed can be autonomously determined by the UE, be pre-defined in the UE or configured by the network node.

[0100] Examples describing the transitioning mechanism from the SA state to the SP state will be disclosed next.

[0101] For example, in OS #1 or in OS #2, the UE and the network node performs a joint RRC and sensing state transition when the UE leaves the RRC connected state either to RRC inactive state, RRC idle state, or when the UE is powered off. The UE creates, continuously maintains, and reports / transmits the sensing context information to the network node. The reporting of the sensing context information can be requested by the network node, or it can be periodic, or event triggered or a hybrid of these schemes (e.g., event triggered periodic), etc.

[0102] Embodiments as performed by the UE 200a where the state transition is performed from the SP state to the SA state will be disclosed next.

[0103] It is here assumed that the UE as operating in the SP state determines, or is instructed, that the UE is to transition to the SA state and that the UE performs one or more operational tasks upon having entered the SA state. Hence, in some embodiments, the at least one operational task is performed after the state transition is performed. The UE can determine that it is going to transition to the SA state based on a rule, which depends on the operational scenario (e.g., OS #1, OS #2 or OS #3) for which the UE is configured. The UE can determine that it is going to transition to the SA state autonomously and / or based on a message received from the network node while the UE was in the SA state earlier and / or based on pre-configuration (e.g., such as by retrieving information from the SIM, or by an application program, etc.). This is described next with examples. In one example, a UE configured in OS #1 or in OS #2 can autonomously determine when the UE is going to transition to the SA state. For example, if a UE configured in OS#i has successfully selected a cell, then the UE can determine that it may soon change, or potentially change, its sensing state from the SP state to the SA state.

[0104] In another example, a UE configured in 0S#3 can autonomously determine when the UE is going to transition to the SA state. For example, having the active sensing intentionally activated (e.g., by a user) may allow the UE to start or resume the transmission and / or reception of the SS if the SS resources / pattern are preconfigured.

[0105] In another example, a UE configured in 0S#3 can determine based on a preconfigured information stored in the UE e.g., a message received from a network node while the UE was in the SA state. For example, the UE may have been preconfigured that the UE is going to transition to the SA state starting from certain reference time (Ts) or after staying in the SP state for certain time duration (Di). The parameters Ts and / or Di maybe pre-defined or configured by the network node. The Ts can be an absolute time, such as UTC, cell or system time, such as SFN number, subframe number, etc.

[0106] Examples of one or more operational tasks which the UE may perform upon entering the SA state are provided next.

[0107] One operational task concerns the UE starting to perform measurements related to the sensing service (e.g., measurements on the SS and / or positioning related signals, etc.) within certain time period (Ti) after the UE enters the SA state. For example, the UE may start the measurements on the SS if the SS receive pattern is pre-configured at the UE.

[0108] One operational task concerns the UE starting to transmit sensing signals related to the sensing service to the network node. The transmission of the sensing signals might start within certain time period (T2) after the UE enters the SA state. For example, the UE may start transmitting the SS if the SS transmit pattern is preconfigured at the UE. One operational task concerns informing the network node 300 of the sensing state transition. In this respect the UE might send a message to the network node including sensing context information to the network node upon the UE having entered the SA state.

[0109] One operational task concerns determining whether or not the UE 200a is capable of participating in the sensing service, and informing the network node 300 accordingly.

[0110] Non-limiting examples of the sensing context information for the present embodiment are provided next.

[0111] One example of sensing context information is information that the UE has transitioned to the SA state. This information may further comprise timing information about the time (e.g., UTC time, cell or system time, etc.) as to when the UE entered the SA state.

[0112] One example of sensing context information is information of one or more reasons for the UE transitioning to the SA state, e.g., based on meeting one or more predefined conditions related to the OS in which the UE is configured, triggered by the UE itself, UE battery power is above some threshold, an emergency or critical event being triggered, etc.

[0113] One example of sensing context information is information of whether the UE intends to be sensed while in the SA state. The UE may further inform whether the UE can actively participate in the sensing procedure e.g., whether the UE can transmit and / or receive SS for the purpose of sensing.

[0114] One example of sensing context information is information of whether the UE will revert to the SP state. This information may further comprise timing information about the time (e.g., UTC time, cell or system time, etc.) as to when the UE will, or might, revert to the SP state.

[0115] In any of the above examples, the UE may in response to having sent the sensing context information receive a configuration message from the network node e.g., containing information about the pattern of the SS transmission and / or reception. The UE may configure the one or patterns and start operating the SS signals according to the configured pattern within certain time period (T3). Reference is now made to Fig. 5 illustrating a method for handling state transitions between sensing states in the UE 200a as performed by the network node 300 according to an embodiment. As noted above, the UE 200a is operable in sensing states comprising a sensing active (SA) state and a sensing passive (SP) state.

[0116] S206: The network node 300 performs, in conjunction with obtaining an indication that that the UE 200a is performing a state transition between the SA state and the SP state, at least one operational task pertaining to a sensing service for the UE 200a. The at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE 200a.

[0117] Embodiments relating to further details of handling state transitions between sensing states in the UE 200a as performed by the network node 300 will now be disclosed with continued reference to Fig. 5.

[0118] Some examples of operational tasks have already been provided and further examples of operational tasks will be provided below. In this respect, the at least one operational task might comprise the network node 300 receiving an update to the sensing context information from the UE 200a.

[0119] There could be different ways in which the network node 200a receives the update to the sensing context information from the UE 200a. In this respect, in some examples, the indication that that the UE 200a is performing the state transition is obtained by any of: the network node 300 receiving information of the state transition from the UE 200a, the network node 300 triggering the UE 200a to perform the state transition, the network node 300 identifying absence of reception of sensing signals from the UE 200a, the network node 300 starting to receive sensing signals from the UE 200a.

[0120] As disclosed above, the UE 200a might indicate, via some signaling message, preference for a certain operational scenario, or mapping, according to which the UE 200a prefers to operate at a certain time. Hence, in some embodiments, the network node 300 is configured to perform (optional) action S202. S202: The network node 300 receives, from the UE 200a, preference for a mapping between the sensing states and the RRC states.

[0121] As further disclosed above, the network node 300 configures the UE 200a via some signaling message to operate in one of the operational scenarios, or mappings, supported by the UE 200a. Hence, in some embodiments, the network node 300 is configured to perform (optional) action S204.

[0122] S204: The network node 300 provides, towards the UE 200a, information of which of the sensing states are mapped to which of the RRC states.

[0123] Embodiments as performed by the network node 300 where, according to the indication, the state transition is performed from the SA state to the SP state will be disclosed next.

[0124] It is here assumed that the network node determines that the UE is going to transition from the SA state to the SP state during a certain period based on one or more rules and that the network node therefore performs one or more operational task. The network node may perform some of the operational tasks even before the UE enters the SP state. The network node may also perform some of the operational tasks after the UE has entered the SP state. The rules for determining that the UE is to transition from the SA state to the SP state are the same as described above with reference to the UE. For example, the transitioning can be determined based on predefined rules, e.g., a UE configured in 0S#2 is in RRC connected state and upon moving to RRC idle state the UE will change its sensing state from SA to SP. Examples of operational tasks are described below.

[0125] When the network node receives the message from the UE informing of the imminent sensing state change, the network node updates the current sensing context information associated with the UE. The network node also marks the sensing context information as the last reported sensing context information in RRC connected state.

[0126] Based on the sensing context information, the network node might decide: (1) if the UE needs to be tracked after leaving the RRC connected state, (2) whether bi-static or mono-static sensing should be used for positioning / tracking, and (3) the sensing signal configuration for tracking the UE. For example, if there is another particular UE- which is sensing capable - in the proximity of the UE, the network may select this particular UE for bi-static sensing. In view of this, examples of corresponding operational tasks as maybe performed by the network node 300 are provided next.

[0127] One operational task concerns determining whether or not the UE 200a is to be sensed in the PS state, and if so which type of sensing is to be used to sense the UE 200a, wherein the type of sensing pertains to bi-static sensing or mono-static sensing.

[0128] One operational task concerns configuring, for bi-static sensing, a UE 200b to transmit sensing signals for sensing the UE 200a.

[0129] One operational task concerns transmitting, for mono-static sensing, sensing signals for sensing the UE 200a.

[0130] In some examples, assume that the UE has requested to be sensed while in the SP state. In this case the network node can also configure another particular UE to transmit SS that allow the network node to perform bi-static sensing. For the selection of the particular UE, and for sensing signal configuration, the network node may use the sensing context information. For example, the initial UE position estimate helps the network node to instruct the other UE to direct the SS towards the UE whose position the network node wants to refine. Alternatively, the network node may use the sensing context information to configure its own sensing signal and perform mono-static sensing of the UE.

[0131] For the sensing signal configuration, the network node might use the current position and velocity of the UE to determine the characteristics of the sensing signal / beam, such as the transmit power (depending on the estimated distance between the other particular UE and the UE to be sensed), sensing beam direction (depending on the relative positions of the UEs) and sensing signal periodicity (depending on the velocity of the UE).

[0132] Embodiments as performed by the network node 300 where, according to the indication, the state transition is performed from the SP state to the SA state will be disclosed next. It is here assumed that the network node determines that the UE is going to transition from the SP state to the SA state during a certain period or has transitioned from the SP state to the SA state based on one or more rules and that the network node therefore performs one or more operational tasks. The network node may perform some of the operational tasks even before the UE enters the SA state. The network node may also perform some of the operational tasks after the UE has entered the SA state. The rules for determining that the UE is to transition from the SP state to the SA state are the same as described above with reference to the UE. For example, the transitioning can be determine based on pre-defined rules e.g., a UE configured in OS #2 is in RRC idle state and upon moving to RRC connected state the UE will change its sensing state from SP to SA. In another example, the network node stores the context of the UE while the UE is in the SP state. Examples of operational tasks are described next.

[0133] One operational task concerns configuring the UE 200a with a pattern of sensing resources for the UE 200a to operate on sensing signals.

[0134] One operational task concerns relieving a UE 200b from sensing the UE 200a.

[0135] One operational task concerns stop transmitting sensing signals for sensing the UE 200a.

[0136] In some examples, the network node configures the UE with the pattern of sensing resources for operating the sensing signals when the UE enters the SA state.

[0137] In some examples, the network node de-configures, or relieves, another UE 200b which was involved in bi-static or multi-static sensing for sensing the UE when the UE was in the SP state. The de-configuring, or relieving, of this another UE 200b may comprise requesting that this another does not transmit and / or receive the SS, thus stopping the bi-static or multi-static sensing.

[0138] One particular embodiment for handling state transitions between sensing states in a UE 200a based on at least some of the above disclosed embodiments will now be disclosed in detail with reference to the signaling diagram of Fig. 6.

[0139] S301: The UE is powered up and enters the RRC idle state. S302: The UE performs an RRC connection setup procedure with the network node. This includes several messages, such as RRC Setup Request and RRC Setup Complete. The RRC Setup Request and / or the RRC Setup Complete messages may include an information element that specifies that the RRC connection contains or will later contain a sensing context information. Sensing context information can be prepared by the UE even before entering RRC connected state.

[0140] S303: The UE resides in the RRC connected state.

[0141] S304: The network node transmits positioning reference signals that the UE measures on.

[0142] S305: The UE, for example based on the measurements but also on other sensing data, refines and enriches the sensing context information while the UE resides in the RRC connected state, for example by adding the current position and velocity of the UE to the sensing context information.

[0143] S306: The UE periodically, or based on certain events, transmits the sensing context information to the network node in a positioning report. The positioning report may also contain updates of the sensing context information, if any of the sensing context information elements have changed or if the network node instructs the UE. Events can be connected to handover events (e.g., measured RSRP falls below some threshold value, etc.).

[0144] S307: The network node forwards the positioning report to the core network 510.

[0145] S308: The network node (optionally) configures another UE 200b for bi-static sensing.

[0146] S309: The other UE and the network node performs bi-static sensing of the UE whose position is tracked.

[0147] S310: The network node updates its sensing context information of the UE whose position is tracked based on the bi-static sensing and transmits a refined positioning report to the core network 510. One particular embodiment for handling state transitions between sensing states in a UE 200a based on at least some of the above disclosed embodiments will now be disclosed in detail with reference to the signaling diagram of Fig. 7.

[0148] S401: The UE resides in the RRC idle state and prepares a state change from the SA state to the SP state.

[0149] S402: UE performs an RRC connection release procedure with the network node. This includes several messages, and also the sensing context information. The sensing context information can be prepared by the UE even before entering the RRC idle state.

[0150] When the UE actively prepares an RRC state transition, the UE can pro-actively signal the sensing context information to the network node. However, when the RRC state change is unplanned or abrupt, the network node still has the latest updated sensing context information due to the UE periodically (or when triggered by an event) reporting the sensing context information.

[0151] In the case of a planned RRC state transition, for example when the human user plans to power-off the UE, the UE indicates to the network node that an RRC state change is imminent, updates the sensing context information and sends the sensing context information to the network node before entering the RRC idle state, the RRC inactive state, or being powered off.

[0152] S403: The UE resides in the RRC idle state, the RRC inactive state, or is powered off. It is here assumed that the UE also has entered the SP state.

[0153] S404: The network node configures another UE 200b for bi-static sensing. Here, the network node might use the sensing context information to configure the bi-static sensing of the UE whose position is tracked.

[0154] S405: The other UE and the network node performs bi-static sensing of the UE whose position is tracked.

[0155] S406: The network node, based on the bi-static sensing, determines the position of the UE whose position is tracked and thereby updates the sensing context information of the UE whose position is tracked. S407: The network node transmits a positioning report to the core network 510.

[0156] Fig. 8 schematically illustrates, in terms of a number of functional units, the components of a UE 200a according to an embodiment. Processing circuitry 210 is provided using any combination of one or more of a suitable central processing unit (CPU), multiprocessor, microcontroller, digital signal processor (DSP), etc., capable of executing software instructions stored in a computer program product 1210a (as in Fig. 12), e.g. in the form of a storage medium 230. The processing circuitry 210 may further be provided as at least one application specific integrated circuit (ASIC), or field programmable gate array (FPGA).

[0157] Particularly, the processing circuitry 210 is configured to cause the UE 200a to perform a set of operations, or steps, as disclosed above. For example, the storage medium 230 may store the set of operations, and the processing circuitry 210 maybe configured to retrieve the set of operations from the storage medium 230 to cause the UE 200a to perform the set of operations. The set of operations maybe provided as a set of executable instructions. Thus the processing circuitry 210 is thereby arranged to execute methods as herein disclosed.

[0158] The storage medium 230 may also comprise persistent storage, which, for example, can be any single one or combination of magnetic memory, optical memory, solid state memory or even remotely mounted memory.

[0159] The UE 200a may further comprise a communications (comm.) interface 220 for communications with other entities, functions, nodes, and devices. As such the communications interface 220 may comprise one or more transmitters and receivers, comprising analogue and digital components.

[0160] The processing circuitry 210 controls the general operation of the UE 200a e.g. by sending data and control signals to the communications interface 220 and the storage medium 230, by receiving data and reports from the communications interface 220, and by retrieving data and instructions from the storage medium 230. Other components, as well as the related functionality, of the UE 200a are omitted in order not to obscure the concepts presented herein. Fig. 9 schematically illustrates, in terms of a number of functional modules, the components of a UE 200a according to an embodiment. The UE 200a of Fig. 9 comprises a perform module 210c configured to perform step S106. The UE 200a of Fig. 9 may further comprise a number of optional functional modules, such as any of an indicate module 210a configured to perform step S102 and a receive module 210b configured to perform step S104. In general terms, each functional module 210a: 210c may be implemented in hardware or in software. Preferably, one or more or all functional modules 210a: 210c may be implemented by the processing circuitry 210, possibly in cooperation with the communications interface 220 and / or the storage medium 230. The processing circuitry 210 may thus be arranged to from the storage medium 230 fetch instructions as provided by a functional module 210a: 210c and to execute these instructions, thereby performing any steps of the UE 200a as disclosed herein.

[0161] Fig. 10 schematically illustrates, in terms of a number of functional units, the components of a network node 300 according to an embodiment. Processing circuitry 310 is provided using any combination of one or more of a suitable central processing unit (CPU), multiprocessor, microcontroller, digital signal processor (DSP), etc., capable of executing software instructions stored in a computer program product 1210b (as in Fig. 12), e.g. in the form of a storage medium 330. The processing circuitry 310 may further be provided as at least one application specific integrated circuit (ASIC), or field programmable gate array (FPGA).

[0162] Particularly, the processing circuitry 310 is configured to cause the network node 300 to perform a set of operations, or steps, as disclosed above. For example, the storage medium 330 may store the set of operations, and the processing circuitry 310 maybe configured to retrieve the set of operations from the storage medium 330 to cause the network node 300 to perform the set of operations. The set of operations maybe provided as a set of executable instructions. Thus the processing circuitry 310 is thereby arranged to execute methods as herein disclosed.

[0163] The storage medium 330 may also comprise persistent storage, which, for example, can be any single one or combination of magnetic memory, optical memory, solid state memory or even remotely mounted memory. The network node 300 may further comprise a communications interface 320 for communications with other functions, nods, entities, and devices. As such the communications interface 320 may comprise one or more transmitters and receivers, comprising analogue and digital components.

[0164] The processing circuitry 310 controls the general operation of the network node 300 e.g. by sending data and control signals to the communications interface 320 and the storage medium 330, by receiving data and reports from the communications interface 320, and by retrieving data and instructions from the storage medium 330. Other components, as well as the related functionality, of the network node 300 are omitted in order not to obscure the concepts presented herein.

[0165] Fig. 11 schematically illustrates, in terms of a number of functional modules, the components of a network node 300 according to an embodiment. The network node 300 of Fig. 11 comprises a perform module 310c configured to perform step S206. The network node 300 of Fig. 11 may further comprise a number of optional functional modules, such as any of a receive module 310a configured to perform step S202 and a provide module 310b configured to perform step S204. In general terms, each functional module 3ioa:3ioc maybe implemented in hardware or in software. Preferably, one or more or all functional modules 3ioa:3ioc maybe implemented by the processing circuitry 310, possibly in cooperation with the communications interface 320 and / or the storage medium 330. The processing circuitry 310 may thus be arranged to from the storage medium 330 fetch instructions as provided by a functional module 3ioa:3ioc and to execute these instructions, thereby performing any steps of the network node 300 as disclosed herein.

[0166] The network node 300 maybe provided as a standalone device or as a part of at least one further device. For example, the network node 300 maybe provided in a node of the radio access network or in a node of the core network 510. Alternatively, functionality of the network node 300 may be distributed between at least two devices, or nodes. These at least two nodes, or devices, may either be part of the same network part (such as a radio access network or the core network 510) or may be spread between at least two such network parts. In general terms, instructions that are required to be performed in real time maybe performed in a device, or node, operatively closer to the cell than instructions that are not required to be performed in real time. Thus, a first portion of the instructions performed by the network node 300 maybe executed in a first device, and a second portion of the instructions performed by the network node 300 may be executed in a second device; the herein disclosed embodiments are not limited to any particular number of devices on which the instructions performed by the network node 300 may be executed. Hence, the methods according to the herein disclosed embodiments are suitable to be performed by a network node 300 residing in a cloud computational environment. Therefore, although a single processing circuitrysio is illustrated in Fig. 10 the processing circuitry 310 maybe distributed among a plurality of devices, or nodes. The same applies to the functional modules 3ioa:3ioc of Fig. 11 and the computer program 1220b of Fig. 12.

[0167] Fig. 12 shows one example of a computer program product 1210a, 1210b comprising computer readable means 1230. On this computer readable means 1230, a computer program 1220a can be stored, which computer program 1220a can cause the processing circuitry 210 and thereto operatively coupled entities and devices, such as the communications interface 220 and the storage medium 230, to execute methods according to embodiments described herein. The computer program 1220a and / or computer program product 1210a may thus provide means for performing any steps of the UE 200a as herein disclosed. On this computer readable means 1230, a computer program 1220b can be stored, which computer program 1220b can cause the processing circuitry 310 and thereto operatively coupled entities and devices, such as the communications interface 320 and the storage medium 330, to execute methods according to embodiments described herein. The computer program 1220b and / or computer program product 1210b may thus provide means for performing any steps of the network node 300 as herein disclosed.

[0168] In the example of Fig. 12, the computer program product 1210a, 1210b is illustrated as an optical disc, such as a CD (compact disc) or a DVD (digital versatile disc) or a Blu-Ray disc. The computer program product 1210a, 1210b could also be embodied as a memory, such as a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), or an electrically erasable programmable read-only memory (EEPROM) and more particularly as a non-volatile storage medium of a device in an external memory such as a USB (Universal Serial Bus) memory or a Flash memory, such as a compact Flash memory. Thus, while the computer program 1220a, 1220b is here schematically shown as a track on the depicted optical disk, the computer program 1220a, 1220b can be stored in anyway which is suitable for the computer program product 1210a, 1210b.

[0169] Fig. 13 shows an example of a communication system 1300 in accordance with some embodiments. In the example, the communication system 1300 includes a telecommunication network 1302 that includes an access network 1304, such as a radio access network (RAN), and a core network 1306, which includes one or more core network nodes 1308. The access network 1304 includes one or more access network nodes, such as network nodes 1310a and 1310b (one or more of which may be generally referred to as network nodes 1310), or any other similar 3rd Generation Partnership Project (3GPP) access nodes or non-3GPP access points. Moreover, as will be appreciated by those of skill in the art, a network node is not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that network nodes include disaggregated implementations or portions thereof. For example, in some embodiments, the telecommunication network 1302 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network 1302 that supports an ORAN specification (e.g., a specification published by the 0-RAN Alliance, or any similar organization) and may operate alone or together with other nodes to implement one or more functionalities of any node in the telecommunication network 1302, including one or more network nodes 1310 and / or core network nodes 1308.

[0170] Examples of an ORAN network node include an open radio unit (0-RU), an open distributed unit (0-DU), an open central unit (O-CU), including an O-CU control plane (O-CU-CP) or an O-CU user plane (O-CU-UP), a RAN intelligent controller (near-real time or non-real time) hosting software or software plug-ins, such as a near-real time control application (e.g., xApp) or a non-real time control application (e.g., rApp), or any combination thereof (the adjective “open” designating support of an ORAN specification). The network node may support a specification by, for example, supporting an interface defined by the ORAN specification, such as an Al, Fl, Wi, El, E2, X2, Xn interface, an open fronthaul user plane interface, or an open fronthaul management plane interface. Moreover, an ORAN access node may be a logical node in a physical node. Furthermore, an ORAN network node may be implemented in a virtualization environment (described further below) in which one or more network functions are virtualized. For example, the virtualization environment may include an O-Cloud computing platform orchestrated by a Service Management and Orchestration Framework via an 0-2 interface defined by the O- RAN Alliance or comparable technologies. The network nodes 1310 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 1312a, 1312b, 1312c, and I3i2d (one or more of which maybe generally referred to as UEs 1312) to the core network 1306 over one or more wireless connections.

[0171] Example wireless communications over a wireless connection include transmitting and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 1300 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that may facilitate or participate in the communication of data and / or signals whether via wired or wireless connections. The communication system 1300 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0172] The UEs 1312 maybe any of a wide variety of communication devices, including wireless devices arranged, configured, and / or operable to communicate wirelessly with the network nodes 1310 and other communication devices. Similarly, the network nodes 1310 are arranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs 1312 and / or with other network nodes or equipment in the telecommunication network 1302 to enable and / or provide network access, such as wireless network access, and / or to perform other functions, such as administration in the telecommunication network 1302.

[0173] In the depicted example, the core network 1306 connects the network nodes 1310 to one or more hosts, such as host 1316. These connections maybe direct or indirect via one or more intermediary networks or devices. In other examples, network nodes maybe directly coupled to hosts. The core network 1306 includes one more core network nodes (e.g., core network node 1308) that are structured with hardware and software components. Features of these components maybe substantially similar to those described with respect to the UEs, network nodes, and / or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 1308. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-concealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and / or a User Plane Function (UPF).

[0174] The host 1316 maybe under the ownership or control of a service provider other than an operator or provider of the access network 1304 and / or the telecommunication network 1302, and maybe operated by the service provider or on behalf of the service provider. The host 1316 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio / video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.

[0175] As a whole, the communication system 1300 of Fig. 13 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system maybe configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and / or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and / or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z- Wave, Near Field Communication (NFC) ZigBee, LiFi, and / or any low-power wide- area network (LPWAN) standards such as LoRa and Sigfox. In some examples, the telecommunication network 1302 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 1302 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 1302. For example, the telecommunications network 1302 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and / or Massive Machine Type Communication (mMTC) / Massive loT services to yet further UEs. The UEs 1312 may comprise the UE 200a and / or the UE 200b. The network nodes 1310 may comprise the network node 300. The UEs 1312 maybe configured to perform the steps S102, S104, S106 or any of the steps of the method performed by the UE 200a. The network nodes 1310 maybe configured to perform S202, S204, S206 or any of the steps of the method performed by the network node 300.

[0176] In some examples, the UEs 1312 are configured to transmit and / or receive information without direct human interaction. For instance, a UE maybe designed to transmit information to the access network 1304 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 1304. Additionally, a UE maybe configured for operating in single- or multi- RAT or multi-standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi -radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC).

[0177] In the example, the hub 1314 communicates with the access network 1304 to facilitate indirect communication between one or more UEs (e.g., UE 1312c and / or I3i2d) and network nodes (e.g., network node 1310b). In some examples, the hub 1314 maybe a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 1314 maybe a broadband router enabling access to the core network 1306 for the UEs. As another example, the hub 1314 maybe a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 1310, or by executable code, script, process, or other instructions in the hub 1314. As another example, the hub 1314 maybe a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 1314 maybe a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 1314 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 1314 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub 1314 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy loT devices.

[0178] The hub 1314 may have a constant / persistent or intermittent connection to the network node 1310b. The hub 1314 may also allow for a different communication scheme and / or schedule between the hub 1314 and UEs (e.g., UE 1312c and / or I3i2d), and between the hub 1314 and the core network 1306. In other examples, the hub 1314 is connected to the core network 1306 and / or one or more UEs via a wired connection. Moreover, the hub 1314 maybe configured to connect to an M2M service provider over the access network 1304 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 1310 while still connected via the hub 1314 via a wired or wireless connection. In some embodiments, the hub 1314 may be a dedicated hub - that is, a hub whose primary function is to route communications to / from the UEs from / to the network node 1310b. In other embodiments, the hub 1314 maybe a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 1310b, but which is additionally capable of operating as a communication start and / or end point for certain data channels.

[0179] Fig. 14 shows a communication diagram of a host 1402 communicating via a network node 1404 with a UE 1406 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as a UE 1312a of Fig. 13 and / or UE 200 of Fig. 8), network node (such as network node 1310a of Fig. 13 and / or network node 300 of Fig. 10), and host (such as host 1316 of Fig. 13) discussed in the preceding paragraphs will now be described with reference to Fig. 14.

[0180] Embodiments of host 1402 include hardware, such as a communication interface, processing circuitry, and memory. The host 1402 also includes software, which is stored in or accessible by the host 1402 and executable by the processing circuitry. The software includes a host application that may be operable to provide a service to a remote user, such as the UE 1406 connecting via an over-the-top (OTT) connection 1450 extending between the UE 1406 and host 1402. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 1450.

[0181] The network node 1404 includes hardware enabling it to communicate with the host 1402 and UE 1406. The connection 1460 maybe direct or pass through a core network (like core network 1306 of Fig. 13) and / or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network maybe a backbone network or the Internet.

[0182] The UE 1406 includes hardware and software, which is stored in or accessible by UE 1406 and executable by the UE’s processing circuitry. The software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via UE 1406 with the support of the host 1402. In the host 1402, an executing host application may communicate with the executing client application via the OTT connection 1450 terminating at the UE 1406 and host 1402. In providing the service to the user, the UE's client application may receive request data from the host's host application and provide user data in response to the request data. The OTT connection 1450 may transfer both the request data and the user data. The UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection 1450.

[0183] The OTT connection 1450 may extend via a connection 1460 between the host 1402 and the network node 1404 and via a wireless connection 1470 between the network node 1404 and the UE 1406 to provide the connection between the host 1402 and the UE 1406. The connection 1460 and wireless connection 1470, over which the OTT connection 1450 may be provided, have been drawn abstractly to illustrate the communication between the host 1402 and the UE 1406 via the network node 1404, without explicit reference to any intermediary devices and the precise routing of messages via these devices. As an example of transmitting data via the OTT connection 1450, in step 1408, the host 1402 provides user data, which maybe performed by executing a host application. In some embodiments, the user data is associated with a particular human user interacting with the UE 1406. In other embodiments, the user data is associated with a UE 1406 that shares data with the host 1402 without explicit human interaction. In step 1410, the host 1402 initiates a transmission carrying the user data towards the UE 1406. The host 1402 may initiate the transmission responsive to a request transmitted by the UE 1406. The request may be caused by human interaction with the UE 1406 or by operation of the client application executing on the UE 1406. The transmission may pass via the network node 1404, in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 1412, the network node 1404 transmits to the UE 1406 the user data that was carried in the transmission that the host 1402 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 1414, the UE 1406 receives the user data carried in the transmission, which maybe performed by a client application executed on the UE 1406 associated with the host application executed by the host 1402.

[0184] In some examples, the UE 1406 executes a client application which provides user data to the host 1402. The user data maybe provided in reaction or response to the data received from the host 1402. Accordingly, in step 1416, the UE 1406 may provide user data, which maybe performed by executing the client application. In providing the user data, the client application may further consider user input received from the user via an input / output interface of the UE 1406. Regardless of the specific manner in which the user data was provided, the UE 1406 initiates, in step 1418, transmission of the user data towards the host 1402 via the network node 1404. In step 1420, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 1404 receives user data from the UE 1406 and initiates transmission of the received user data towards the host 1402. In step 1422, the host 1402 receives the user data carried in the transmission initiated by the UE 1406.

[0185] One or more of the various embodiments improve the performance of OTT services provided to the UE 1406 using the OTT connection 1450, in which the wireless connection 1470 forms the last segment. More precisely, the teachings of these embodiments may improve the position estimation of a UE and improve tracking of a UE and thereby provide benefits such as keeping track of the UE even when the UE changes sensing state from sensing active state to sensing passive.

[0186] In an example scenario, factory status information maybe collected and analyzed by the host 1402. As another example, the host 1402 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 1402 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, the host 1402 may store surveillance video uploaded by a UE. As another example, the host 1402 may store or control access to media content such as video, audio, VR or AR which it can broadcast, multicast or unicast to UEs. As other examples, the host 1402 maybe used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing and / or transmitting data.

[0187] In some examples, a measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 1450 between the host 1402 and UE 1406, in response to variations in the measurement results. The measurement procedure and / or the network functionality for reconfiguring the OTT connection may be implemented in software and hardware of the host 1402 and / or UE 1406. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 1450 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 1450 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not directly alter the operation of the network node 1404. Such procedures and functionalities maybe known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency and the like, by the host 1402. The measurements maybe implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 1450 while monitoring propagation times, errors, etc.

[0188] The inventive concept has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the inventive concept, as defined by the appended patent claims.

Claims

CLAIMS1. A method for handling state transitions between sensing states in a user equipment, UE (200a), wherein the UE (200a) is operable in sensing states comprising a sensing active, SA, state and a sensing passive, SP, state, wherein the method is performed by the UE (200a), and wherein the method comprises: performing (S106), in conjunction with performing a state transition between the SA state and the SP state, at least one operational task pertaining to a sensing service for the UE (200a), wherein the at least one operational task is, from a set of operational tasks, selected according to: sensing context information that holds information about a sensing service status of the UE (200a), current sensing state of the UE (200a), and to which one or more radio resource control, RRC, states the current sensing state is mapped.

2. The method according to claim 1, wherein the at least one operational task comprises transmitting the sensing context information to a network node (300).

3. The method according to claim 1 or 2, wherein the UE (200a) is configured to operate on sensing signals in the SA state but not in the SP state.

4. The method according to claim 3, wherein operate on the sensing signals comprises any, or any combination, of: transmit the sensing signals; receive the sensing signals; and process the sensing signals.

5. The method according to any preceding claim, wherein the sensing context information pertains to any, or any combination, of: indication of positioning and / or tracking of the UE (200a); indication of a change of sensing state; position and / or velocity of the UE (200a); positioning and / or tracking method supported by the UE (200a); and UE capability information.

6. The method according to any preceding claim, wherein the sensing context information pertains to any, or any combination, of: size of the UE (200a); and surface material properties of the UE (200a).

7. The method according to any preceding claim, wherein the sensing context information pertains to any, or any combination, of: identification of any UEs (200b)in proximity of the UE (200a); and information how the UE (200a) has acquired the identification of any UEs (200b) in proximity of the UE (200a).

8. The method according to claim 5, 6, or 7, wherein the sensing context information further pertains to any, or any combination, of: security information of the UE (200a) such as an encryption key, or an identifier of the encryption key.

9. The method according to any preceding claim, wherein the SA state is mapped to the UE (200a) being in any of the RRC states: disconnected / idle, RRC connected, RRC connected inactive, and wherein the SP state is mapped to the UE (200a) being powered off.

10. The method according to any of claims 1 to 8, wherein the SA state is mapped to the UE (200a) being in any of the RRC states: RRC connected, RRC connected inactive, and wherein the SP state is mapped to the UE (200a) being in the RRC state disconnected / idle or the UE (200a) being powered off.

11. The method according to any of claims 1 to 8, wherein the SA state is mapped to the UE (200a) being in one of the RRC states: disconnected / idle, RRC connected, RRC connected inactive, and wherein the SP state is mapped to the UE (200a) being in any RRC state except said one of the RRC states or the UE (200a) being powered off.

12. The method according to any preceding claim, wherein the method further comprises: indicating (S102), to a network node (300), preference for a mapping between the sensing states and the RRC states.

13. The method according to any preceding claim, wherein the method further comprises: receiving (S104), from a network node (300), information of which of the sensing states are mapped to which of the RRC states.

14. The method according to any preceding claim, wherein that the UE (200a) is to perform the state transition between the SA state and the SP state is determinedbased on a rule that depends on which of the sensing states are mapped to which of the RRC states.

15. The method according to any of claims 1 to 13, wherein that the UE (200a) is to perform the state transition between the SA state and the SP state is determined autonomously, based on information received from a network node (300), based on configuration, or based on execution of an application program in the UE (200a).

16. The method according to any preceding claim, wherein the state transition is performed from the SA state to the SP state.

17. The method according to claim 16, wherein the at least one operational task is performed before the state transition is performed.

18. The method according to claim 16 or 17, wherein the at least one operational task further comprises any, or any combination, of: completing any ongoing measurements related to the sensing service; completing any transmissions of sensing signals related to the sensing service to a network node (300); informing the network node (300) of the imminent sensing state transition; determining whether or not the UE (200a) is to be sensed in the PS state, and informing the network node (300) accordingly; and postponing transitioning from the SA state to the PS state.

19. The method according to any of claims 1 to 15, wherein the state transition is performed from the SP state to the SA state.

20. The method according to claim 19, wherein the at least one operational task is performed after the state transition is performed.

21. The method according to claim 19 or 20, wherein the at least one operational task further comprises any, or any combination, of: starting to perform measurements related to the sensing service; starting to transmit sensing signals related to the sensing service to a network node (300); informing the network node (300) of the sensing state transition; anddetermining whether or not the UE (200a) is capable of participating in the sensing service, and informing the network node (300) accordingly.

22. A method for handling state transitions between sensing states in a user equipment, UE (200a), wherein the UE (200a) is operable in sensing states comprising a sensing active, SA, state and a sensing passive, SP, state, wherein the method is performed by a network node (300), and wherein the method comprises: performing (S206), in conjunction with obtaining an indication that that the UE (200a) is performing a state transition between the SA state and the SP state, at least one operational task pertaining to a sensing service for the UE (200a), wherein the at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE (200a).

23. The method according to claim 22, wherein the at least one operational task comprises receiving an update to the sensing context information from the UE (200a).

24. The method according to claim 22 or 23, wherein the indication that that the UE (200a) is performing the state transition is obtained by any of: the network node (300) receiving information of the state transition from the UE (200a); the network node (300) triggering the UE (200a) to perform the state transition; the network node (300) identifying absence of reception of sensing signals from the UE (200a); and the network node (300) starting to receive sensing signals from the UE (200a).

25. The method according to any of claims 22 to 24, wherein the sensing context information pertains to any, or any combination, of: indication of positioning and / or tracking of the UE (200a); indication of a change of sensing state; position and / or velocity of the UE (200a); positioning and / or tracking method supported by the UE (200a); and UE capability information.

26. The method according to any of claims 22 to 25, wherein the sensing context information pertains to any, or any combination, of: size of the UE (200a); and surface material properties of the UE (200a).

27. The method according to any of claims 22 to 26, wherein the sensing context information pertains to any, or any combination, of: identification of any UEs (200b) in proximity of the UE (200a); and information how the UE (200a) has acquired the identification of any UEs (200b) in proximity of the UE (200a).

28. The method according to any of claims 25, 26, or 27, wherein the sensing context information further pertains to any, or any combination, of: security information of the UE (200a), such as an encryption key, or an identifier of the encryption key.

29. The method according to any of claims 22 to 28, wherein the UE (200a) further is operable in a set of radio resource control, RRC, states, and wherein the method further comprises: receiving (S202), from the UE (200a), preference for a mapping between the sensing states and the RRC states.

30. The method according to any of claims 22 to 29, wherein the UE (200a) further is operable in a set of radio resource control, RRC, states, and wherein the method further comprises: providing (S204), towards the UE (200a), information of which of the sensing states are mapped to which of the RRC states.

31. The method according to any of claims 22 to 30, wherein, according to the indication, the state transition is performed from the SA state to the SP state.

32. The method according to claim 31, wherein the at least one operational task further comprises any, or any combination, of: determining whether or not the UE (200a) is to be sensed in the PS state, and if so which type of sensing is to be used to sense the UE (200a), wherein the type of sensing pertains to bi-static sensing or mono-static sensing; configuring, for bi-static sensing, a UE (200b) to transmit sensing signals for sensing the UE (200a); and transmitting, for mono-static sensing, sensing signals for sensing the UE (200a).33- The method according to any of claims 22 to 30, wherein, according to the indication, the state transition is performed from the SP state to the SA state.

34. The method according to claim 33, wherein the at least one operational task further comprises any, or any combination, of: configuring the UE (200a) with a pattern of sensing resources for the UE (200a) to operate on sensing signals; relieving a UE (200b) from sensing the UE (200a); and stop transmitting sensing signals for sensing the UE (200a).

35. A user equipment, UE (200a) for handling state transitions between sensing states in the UE (200a), wherein the UE (200a) is operable in sensing states comprising a sensing active, SA, state and a sensing passive, SP, state, the UE (200a) comprising processing circuitry (210), the processing circuitry being configured to cause the UE (200a) to: perform, in conjunction with performing a state transition between the SA state and the SP state, at least one operational task pertaining to a sensing service for the UE (200a), wherein the at least one operational task is, from a set of operational tasks, selected according to: sensing context information that holds information about a sensing service status of the UE (200a), current sensing state of the UE (200a), and to which one or more radio resource control, RRC, states the current sensing state is mapped.

36. A user equipment, UE (200a) for handling state transitions between sensing states in the UE (200a), wherein the UE (200a) is operable in sensing states comprising a sensing active, SA, state and a sensing passive, SP, state, the UE (200a) comprising: a perform module (210c) configured to perform, in conjunction with performing a state transition between the SA state and the SP state, at least one operational task pertaining to a sensing service for the UE (200a), wherein the at least one operational task is, from a set of operational tasks, selected according to: sensing context information that holds information about a sensing service status of the UE (200a),current sensing state of the UE (200a), and to which one or more radio resource control, RRC, states the current sensing state is mapped.

37. The UE (200a) according to claim 35 or 36, further being configured to perform the method according to any of claims 2 to 21.

38. A network node (300) for handling state transitions between sensing states in a user equipment, UE (200a), wherein the UE (200a) is operable in sensing states comprising a sensing active, SA, state and a sensing passive, SP, state, the network node (300) comprising processing circuitry (310), the processing circuitry being configured to cause the network node (300) to: perform, in conjunction with obtaining an indication that that the UE (200a) is performing a state transition between the SA state and the SP state, at least one operational task pertaining to a sensing service for the UE (200a), wherein the at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE (200a).

39. A network node (300) for handling state transitions between sensing states in a user equipment, UE (200a), wherein the UE (200a) is operable in sensing states comprising a sensing active, SA, state and a sensing passive, SP, state, the network node (300) comprising: a perform module (310c) configured to perform, in conjunction with obtaining an indication that that the UE (200a) is performing a state transition between the SA state and the SP state, at least one operational task pertaining to a sensing service for the UE (200a), wherein the at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE (200a).

40. The network node (300) according to claim 38 or 39, further being configured to perform the method according to any of claims 23 to 34.

41. A computer program (1220a) for handling state transitions between sensing states in a user equipment, UE (200a), wherein the UE (200a) is operable in sensing states comprising a sensing active, SA, state and a sensing passive, SP, state, thecomputer program comprising computer code which, when run on processing circuitry (210) of the UE (200a), causes the UE (200a) to: perform (S106), in conjunction with performing a state transition between the SA state and the SP state, at least one operational task pertaining to a sensing service for the UE (200a), wherein the at least one operational task is, from a set of operational tasks, selected according to: sensing context information that holds information about a sensing service status of the UE (200a), current sensing state of the UE (200a), and to which one or more radio resource control, RRC, states the current sensing state is mapped.

42. A computer program (1220b) for handling state transitions between sensing states in a user equipment, UE (200a), wherein the UE (200a) is operable in sensing states comprising a sensing active, SA, state and a sensing passive, SP, state, the computer program comprising computer code which, when run on processing circuitry (310) of a network node (300), causes the network node (300) to: perform (S206), in conjunction with obtaining an indication that that the UE (200a) is performing a state transition between the SA state and the SP state, at least one operational task pertaining to a sensing service for the UE (200a), wherein the at least one operational task is, from a set of operational tasks, selected according to sensing context information that holds information about a sensing service status of the UE (200a).

43. A computer program product (1210a, 1210b) comprising a computer program (1220a, 1220b) according to at least one of claims 41 and 42, and a computer readable storage medium (1230) on which the computer program is stored.

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