Switching operational modes in a communication link between a user equipment, UE, and a node

Abstract

A method performed by a User Equipment, UE, of switching operational modes in a communication link between said UE and a node, wherein said operational modes specify how said UE and said node communicate, said method comprising the steps of communicating, by said UE, with said node using a first operational mode; performing, by said UE, sensing for determining degradation of quality of said communication link between said UE and said node while using the first operational mode, and switching, by said UE, from said first operational mode to a second operational mode, different to said first operational mode, based on said determined degradation, for maintaining said communication link between said UE and said node.

Description

[0001] Title

[0002] Switching operational modes in a communication link between a User Equipment, UE, and a node.

[0003] Technical field

[0004] The present disclosure generally relates to the field of communication and, more specifically, to switching operational modes in a communication link between a User Equipment, UE, and a node.

[0005] Background

[0006] Radar, radio detection and ranging, is a widely deployed wireless sensing technology that uses radio waves to determine the distance (range), angle, or instantaneous linear velocity of objects. Other sensing technologies, including nonRadio Frequency sensors, are also used in other application areas such as, for example, cameras, accelerometers, gyroscopes, etc.

[0007] Integrated Sensing and Communication (ISAC) refers to the sensing capabilities provided by the same wireless communication system and infrastructure as the one used for communication. More specifically, ISAC technology uses communication signals for radar sensing purposes The term ISAC may interchangeably be called as harmonized communication and sensing (HCAS), joint communication and sensing (JCAS) etc.

[0008] The sensing can be used for a wide range of monitoring and detection applications such as for monitoring vehicles, traffic pattern, unmanned aerial vehicle (UAV), weather, pollution, real-time monitoring in smart cities, factories, homes, corporate environment, etc. The sensing can further be used for enhancing operation of intelligent and / or autonomous transportation, UAV, industrial automation, etc.

[0009] The communication and sensing may use the same or different waveforms. The sensing signals may have their own frame structure. Alternatively, they may also be based on existing signals (e.g., Synchronization Signal Block (SSB)) but in different time-frequency resources than used by the communication (e.g., cell defined SSB (CD-SSB)). The radio resources (e.g., RBs) used for communication and sensing can be configured or allocated using time division multiplexing (TDM) or frequency division multiplexing (FDM). In general, there can be different mechanisms for sharing the resources between communication and sensing operations such as, for example, shared spectrum, shared hardware, shared baseband / processing / memory resources, sharing of protocol stacks, etc. There can be loose or tight integration of sensing and communication depending on whether the existing 5G-NR architecture is used or not.

[0010] In 5G New Radio (NR), sidelink (SL) communications facilitate the direct information exchange between nearby UE devices over the PC5 interface. Specifically, since Rel-16, NR supports broadcast, groupcast, and unicast SL communications. When the communicating UEs are under network coverage, the gNB or eNB assigns and manages the SL radio resources for direct (i.e., device-to-device) communications. SL radio resources can be dedicated to sidelink communications, or they may be shared with resources used for uplink (UL) cellular communications. When the communication resources are assigned and managed for in-coverage SL communications by the network, the communication mode is referred to as Mode 1 SL communications.

[0011] In contrast, in Mode 2, UEs can autonomously select their time and frequency SL resources out of a predefined and preconfigured resource pool. Mode 2 can, thus, be used even when the UEs are out of coverage. In this mode, UEs can operate over the SL using a dynamic or a semi-persistent scheduling scheme. The dynamic scheme may select the used resources for each transport block separately, whereas in semi-persistent scheduling, the same resources are used for several subsequent transport blocks. The semi-persistent scheme can be enabled or disabled in a resource pool by pre- and re-configuring the SL resource pool by the network node.

[0012] Several resource allocation mechanisms for Mode 1 and Mode 2 communications have been studied by both the 3GPP and the academic and industrial research communities. Also, several supporting elements for synchronization, scheduling, power control, resource allocation, channel estimation, etc., have been standardized by the 3rdGeneration Partnership Project (3GPP). Specifically, the NR sidelink can be used for unicast, groupcast and broadcast at the physical layer and corresponding resource allocation schemes are implemented in the NR specifications. There currently exist certain challenge(s), however. For example, in mobile communication due to the relative motion between the UE and movable objects (e.g., vehicle, drone, human, animal, etc.), the objects can partially or fully obstruct a radio link used by the UE. For example, the communication link between the UE and its serving cell or between the UE and another UE (in SL operation) can be severely degraded or even blocked due to the intruding object(s).

[0013] In existing solutions, the impact of such intrusion / obstruction is implicitly detected by means of significant loss of the signal quality (e.g., Signal to Noise Ratio (SNR), Signal Interference to Noise Ratio (SINR), Reference Signal Received Quality (RSRQ), etc.) typically observed or estimated by the UE. The existing solution is to perform a cell change (e.g., handover, cell reselection, etc.) provided that the connection with the target cell can restore the communication. This implicit detection mechanism is inherently a reactive procedure. Therefore, one drawback of the classical mechanism is longer delay in detecting the radio link problem. Furthermore, cell change may cause significant interruption of several 10’s of ms. Both longer delay and long interruptions cause throughput loss and are not suitable for certain services (e.g., Extended Reality (XR), real time video) that persistently require high quality of service (QoS).

[0014] In mobile communication due to the relative motion between the UE and movable objects (e.g., vehicle, drone, human, animal etc), the objects can partially or fully obstruct a radio link used by the UE. For example, the communication link between the UE and its serving cell or between the UE and another UE (in SL operation) can be severely degraded or even blocked due to the intruding object(s). In existing solutions, the impact of such intrusion / obstruction is implicitly detected by means of significant loss of the signal quality (e.g., SNR, SINR, RSRQ etc) typically observed or estimated by the UE.

[0015] The existing solution is to perform a cell change (e.g., handover, cell reselection etc) provided that the connection with the target cell can restore the communication. This implicit detection mechanism is inherently a reactive procedure. Therefore, one drawback of the classical mechanism is longer delay in detecting the radio link problem. Furthermore, cell change may cause significant interruption of several 1O’s of ms. Both longer delay and long interruptions cause throughput loss and are not suitable for certain services (e.g., XR, real time video) that persistently require high quality of service (QoS).

[0016] Summary

[0017] It would be advantageous to achieve a method for switching operational modes in a communication link between a User Equipment, UE, and a node. It would further be advantageous to achieve a corresponding User Equipment.

[0018] In a first aspect of the present disclosure, there is provided a method performed by a User Equipment, UE, of switching operational modes in a communication link between said UE and a node, wherein said operational modes specify how said UE and said node communicate. The method comprising the steps of: communicating, by said UE, with said node using a first operational mode; performing, by said UE, sensing for determining degradation of quality of said communication link between said UE and said node while using the first operational mode switching, by said UE, from said first operational mode to a second operational mode, different to said first operational mode, based on said determined degradation, for maintaining said communication link between said UE and said node.

[0019] The inventors have found that it may be beneficial to perform sensing for determining degradation of quality of the communication link between the UE and the node while using the operational mode.

[0020] Such determination may be an instantaneous determination, wherein the sensing indicates that the quality is instantaneously degraded. Such determination may also encompass an estimation wherein it is estimated, or predicted, that quality of the communication link is degraded.

[0021] Based on this determination, the UE switches from the first operation mode to the second operational mode to maintain the communication link between the UE and the node. User Equipment, UE, such as a smartphone, may employ various operational modes to connect with telecommunication networks and other devices. One of the most used operational mode is the direct or UE-to-Network, U2N, connection, where the UE communicates directly with the base station, for example gNB, to access cellular services. This is the typical mode for making calls, using mobile data, and running most apps.

[0022] Sidelink, SL, also known as UE-to-UE, U2U, communication, is another form of an operational mode and enables direct communication between UEs, independent of or in conjunction with the cellular network. Sidelink can be used for proximity-based services, public safety applications, and offloading network traffic, and it can also function even when cellular coverage is unavailable.

[0023] Relaying is an operation model which involves a UE acting as an intermediary to forward signals, extending network coverage. This can be either U2N relaying, where a UE relays communication for another UE to the gNB, or U2U / Sidelink relaying, where a UE relays sidelink communication between other UEs.

[0024] Another operational mode encompasses the use of a Wide Area Network, WAN, for connection to the telecommunication network.

[0025] In accordance with the present disclosure, operational modes specfy how the UE connects to the other node. These operational modes may dictate the path data takes (e.g., directly to a base station or through other devices) and, on top of that, may specify the type of communication protocol used, and the level of network involvement.

[0026] In an example, the step of performing said sensing comprises: performing, by said UE, said sensing using radio resources other than radio resources used for communication using said first operational mode.

[0027] The sensing may thus use a frequency spectrum different to a frequency spectrum used for communication using said first operational mode and / or may sense in time instances different to a time instances used for communication using said first operational mode.

[0028] In a second aspect of the present disclosure, there is provided a User Equipment, UE, arranged for switching operational modes in a communication link between said UE and a node, wherein said operational modes specify how said UE and said node communicate. The UE comprising processing circuitry arranged for: communicating with said node using a first operational mode; performing sensing for determining degradation of quality of said communication link between said UE and said node while using the first operational mode switching from said first operational mode to a second operational mode, different to said first operational mode, based on said determined degradation, for maintaining said communication link between said UE and said node.

[0029] It is noted that the advantages as explained with reference to the first aspect of the present disclosure, being the method for switching operational modes, are also applicable to the second aspect of the present disclosure, being the UE arranged for switching operational modes.

[0030] In a third aspect of the present disclosure, there is provided a computer program product comprising a computer readable medium having instructions stored thereon which, when executed by a User Equipment, UE, cause said UE to implement a method in accordance with any of the previous examples.

[0031] In the appended figures, similar components and / or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.

[0032] The above and other aspects of the disclosure will be apparent from and elucidated with reference to the examples described hereinafter.

[0033] Brief description of the drawings

[0034] Fig. 1 discloses different radar settings that can be deployed using cellular base station and UE;

[0035] Fig. 2 discloses a first example scenario where a UE1 is served by a first cell;

[0036] Fig. 3 discloses a second example scenario where a UE1 is served by a first cell; Fig. 4 discloses a third example scenario where UE1 is not served by Celli , i.e., UE1 is out of network coverage;

[0037] Fig. 5 discloses a fourth example scenario where UE1 is engaged in a Sidelink operation with UE2;

[0038] Fig. 6 discloses an example of UE1 switching its operational mode for communication procedure from WAN to SL to maintain communication with regard to Celli ;

[0039] Fig. 7 discloses an example of UE1 switching its operational mode for communication procedure from direct SL path to UE to UE (U2U) SL relay;

[0040] Fig. 8 discloses an example of a UE in accordance with the present disclosure.

[0041] Detailed description

[0042] It is noted that in the description of the figures, same reference numerals refer to the same or similar components performing a same or essentially similar function.

[0043] A more detailed description is made with reference to particular examples, some of which are illustrated in the appended drawings, such that the manner in which the features of the present disclosure may be understood in more detail. It is noted that the drawings only illustrate typical examples and are therefore not to be considered to limit the scope of the subject matter of the embodiments. The drawings are incorporated for facilitating an understanding of the disclosure and are thus not necessarily drawn to scale. Advantages of the subject matter as claimed will become apparent to those skilled in the art upon reading the description in conjunction with the accompanying drawings.

[0044] The ensuing description provides preferred exemplary embodiment(s) only, and is not intended to limit the scope, applicability or configuration of the disclosure. Rather, the ensuing description of the preferred exemplary embodiment(s) will provide those skilled in the art with an enabling description for implementing a preferred exemplary embodiment of the disclosure, it being understood that various changes may be made in the function and arrangement of elements, including combinations of features from different embodiments, without departing from the scope of the disclosure.

[0045] Unless the context clearly requires otherwise, throughout the description and the embodiments, the words "comprise," "comprising," and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to." As used herein, the terms "connected," "coupled," or any variant thereof means any connection or coupling, either direct or indirect, between two or more elements; the coupling or connection between the elements can be physical, logical, electromagnetic, or a combination thereof. Additionally, the words "herein," "above," "below," and words of similar import, when used in this application, refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the Detailed Description using the singular or plural number may also include the plural or singular number respectively. The word "or," in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list.

[0046] These and other changes can be made to the technology in light of the following detailed description. While the description describes certain examples of the technology, and describes the best mode contemplated, no matter how detailed the description appears, the technology can be practiced in many ways. Details of the system may vary considerably in its specific implementation, while still being encompassed by the technology disclosed herein. As noted above, particular terminology used when describing certain features or aspects of the technology should not be taken to imply that the terminology is being redefined herein to be restricted to any specific characteristics, features, or aspects of the technology with which that terminology is associated. In general, the terms used in the following embodiments should not be construed to limit the technology to the specific examples disclosed in the specification, unless the Detailed Description section explicitly defines such terms. Accordingly, the actual scope of the technology encompasses not only the disclosed examples, but also all equivalent ways of practicing or implementing the technology under the embodiments. Some of the examples contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

[0047] As used herein, ‘node’ can be a network node or a UE. Examples of network nodes are NodeB, base station (BS), multi-standard radio (MSR) radio node such as MSR BS, eNodeB (eNB), gNodeB (gNB), Master eNB (MeNB), Secondary eNB (SeNB), integrated access backhaul (IAB) node, network controller, radio network controller (RNC), base station controller (BSC), relay, donor node controlling relay, base transceiver station (BTS), Central Unit (e.g. in a gNB), Distributed Unit (e.g. in a gNB), Baseband Unit, Centralized Baseband, C-RAN, access point (AP), transmission points, transmission nodes, Remote Radio Unit (RRU), Remote Radio Head (RRH), nodes in distributed antenna system (DAS), core network node (e.g. Mobile Switching Center (MSC), Mobility Management Entity (MME), etc.), Operations & Maintenance (O&M), Operations Support System (OSS), Self Organizing Network (SON), positioning node (e.g. E-SMLC), etc. The terms network node and radio network node are used interchangeably herein.

[0048] Another example of a node is user equipment (UE), which is a nonlimiting term and refers to any type of wireless device communicating with a network node and / or with another UE in a cellular or mobile communication system. Examples of UE are target device, device to device (D2D) UE, vehicular to vehicular (V2V), machine type UE, MTC UE or UE capable of machine to machine (M2M) communication, Personal Digital Assistant (PDA), Tablet, mobile terminals, smart phone, laptop embedded equipment (LEE), laptop mounted equipment (LME), Unified Serial Bus (USB) dongles, etc.

[0049] The term radio access technology (RAT), may refer to any RAT such as, for example, Universal Terrestrial Radio Access Network (UTRA), Evolved Universal Terrestrial Radio Access Network (E-UTRA), narrow band internet of things (NB-loT), WiFi, Bluetooth, next generation RAT, NR, 4G, 5G, 6G, etc. Any of the equipment denoted by the terms node, network node or radio network node may be capable of supporting a single or multiple RATs.

[0050] The term communication signal may comprise any type of signal or radio signal used for operation (e.g., transmission and / or reception) between a UE and a network node in any wireless communication operation e.g., cellular system such as 5G-NR etc.

[0051] The term sensing signal may comprise any type of signal or radio signal used for operation (e.g., transmission and / or reception) between a radio node and a sensing device or between a radio node and an object for the purpose of sensing etc. The sensing signal may also be called as radar signal. The radio node may be a UE or a network node such as a BS, access point, etc.

[0052] The term time resource used herein may correspond to any type of physical resource or radio resource expressed in terms of length of time. Examples of time resources are symbol, time slot, subframe, radio frame, transmission time interval (TTI), interleaving time, slot, sub-slot, mini-slot, system frame number (SFN) cycle, hyper-SFN (H-SFN) cycle, etc.

[0053] The term object of interest or simply object (01) can be the one which is associated with one or more of the following characteristics or properties:

[0054] An object, which is expected to be located in a certain region, which can be 1-dimensional, 2-dimensional or 3-dimensional space, particular place or location (e.g., building compound, portion of road, roundabout, side walk, etc.).

[0055] An object, which is expected to move in certain direction and / or with certain speed in certain region.

[0056] An object, which has certain physical characteristics (e.g., bike, vehicle, animal, human, etc.) and / or morphology spherical object (e.g., spherical, cubical, etc.).

[0057] According to certain examples, systems, methods and techniques are provided for proactively detecting and / or predicting communication link quality degradation and enabling the network and / or the UE to take suitable action in advance and thereby to reduce or even avoid delays and interruptions due to radio link failure or radio link degradation.

[0058] In an example scenario, a first UE (UE1) is configured to perform or may currently be performing an ICAS / JCAS operation.

[0059] According to an example, which is related to a method in UE1 , the UE1 is configured to perform a communication procedure using a first operational mode (0M1) and sensing procedure using 0M1 or a second operational mode (0M2). The UE determines the impact on the performance of the communication procedure based on the sensing procedure and changes the operation mode of the communication procedure from OM1 to OM2 based on the determined impact of the sensing procedure on the communication procedure. Therefore, OM1 and OM2 are operational modes before and after the mode switching actions respectively.

[0060] In an example, there is provided a method performed by a User Equipment, UE, of switching operational modes in a communication link between said UE and a node, wherein said operational modes specify how said UE and said node communicate

[0061] The method comprising the steps of: communicating, by said UE, with said node using a first operational mode; performing, by said UE, sensing for determining degradation of quality of said communication link between said UE and said node while using the first operational mode switching, by said UE, from said first operational mode to a second operational mode, different to said first operational mode, based on said determined degradation, for maintaining said communication link between said UE and said node.

[0062] An example scenario comprises of a first UE (UE1) engaged in an integrated communication and sensing operation in a wireless communication network.

[0063] In a particular example, UE1 is served by a first cell (Celli), which is managed or served by a first network node (NN1). UE1 is engaged or expected to be engaged in communication between itself and at least Celli by operating communication signal (CS) or more specifically WAN CS or Uu CS (WAN-CS). UE1 may further operate the CS between itself and one or more additional cells e.g., another serving cell, a neighbor cell, etc.

[0064] In another particular example, UE1 is engaged in directional communication with another UE, a second UE (UE2) over sidelink (SL).

[0065] In this case, UE1 operates a SL communication signal (SL-CS) between itself and UE2 over the SL.

[0066] As used herein, the term CS refers to any type of CS such as, for example, WAN-CS or Uu-CS and / or SL-CS. The term operating of the CS or operation of the CS may comprise UE1 receiving the CS from another node, a second node (Node2) and / or UE1 transmitting the CS to Node2. Examples of Node2 are Celli , UE2, etc. Examples of CS are physical signals (e.g., RS such as SSB, CSI-RS, SRS, DMRS, etc.), physical channel (e.g., data channel such as PDSCH / PUSCH, control channel such as PDCCH / PUCCH, broadcast channel such as PBCH, paging channels, etc.), etc. UE1 is further configured by a network node and / or autonomously to perform sensing operation. The sensing operation may comprise performing measurements on a sensing signal (SS) received and / or transmitted by UE1.

[0067] FIGURE 1 illustrates different radar settings that can be deployed using cellular base stations and user equipment (UE) devices. Typically, the goal is to detect and localize a passive (non-connected) object of interest, which is illustrated in FIGURE 1 by detecting an unconnected human user), without an active device using monostatic, bistatic, or multistatic sensing. The bistatic sensing can be realized by using two network nodes (e.g., eNB, gNB, base station, etc.), one network node, and a UE or two UE devices. Alternatively, multistatic sensing can also be realized by designating one or more transmitters (e.g., a network node, UE, etc.) and several sensing signal receiver nodes, as shown on the right side of FIGURE 1.

[0068] Non-limiting examples of sensing operations in which UE1 is involved and which are most relevant for this invention are described below with regard to FIGURES 2.

[0069] For example, FIGURE 2 illustrates a first example scenario where a UE1 is served by a first cell (Celli) for communication purpose using CS and is also configured to perform bi-static sensing by operating a sensing signal (SS) between itself and Celli to detect the object of interest (01) (e.g., vehicle, cycle, human, etc.). UE1 receives the sensing signal (SSr), which is the reflected part or reflected component or reflected path of the transmitted sensing signal (SSt) transmitted by Celli .

[0070] Here, the node is a base station in a telecommunication network, for example a gNB or an eNB. The step of performing said sensing comprises receiving, by said UE, a sensing signal, determining, by said UE, that a quality of said received sensing signal is degrading.

[0071] FIGURE 3 illustrates a second example scenario where UE1 served by Celli for communication purpose using CS and is also configured to perform a monostatic sensing operation by operating a SS between itself and an 01 (e.g., vehicle, cycle, human, etc.). UE1 receives the sensing signal (SSr), which is the reflected part or reflected component or reflected path of the transmitted sensing signal (SSt) transmitted by UE1

[0072] Here, the node is also a base station in the telecommunication network. The step of performing said sensing then comprises transmitting, by said UE, said sensing signal, wherein said received sensing signal is a reflection of said transmitted sensing signal, receiving, by said UE, a sensing signal, determining, by said UE, that a quality of said received sensing signal is degrading.

[0073] FIGURE 4 illustrates a third exemplary scenario where UE1 is not served by Celli , i.e., UE1 is out of network coverage, and is configured to perform bi-static sensing by operating SS between itself and UE2 for detecting 01 , according to certain embodiments. In the example scenario, the UE1 is engaged in a sidelink (SL) operation between itself and UE2 for performing both communication operation and sensing operation. UE1 receives SSr, which is the reflected part or reflected component or reflected path of SSt transmitted by UE2 on the SL in a bi-static sensing scenario. UE2 may or may not be served by Celli or by another cell i.e. For example, UE2 may be in-network coverage or out of network coverage.

[0074] Here, the node is a further UE. The step of performing said sensing comprises receiving, by said UE, a sensing signal, determining, by said UE, that a quality of said received sensing signal is degrading.

[0075] FIGURE 5 illustrates a fourth exemplary scenario where UE1 is engaged in a SL operation with UE2 for performing communication operation and is configured to perform a monostatic sensing by operating a SS between itself and 01 , according to certain embodiments. In this example scenario, UE1 receives SSr, which is the reflected part or reflected component or reflected path of SSt transmitted by UE1 on the SL in a mono-static sensing scenario. UE2 may be in-network coverage or out of network coverage.

[0076] Here, the node is also a further UE. The step of performing said sensing then comprises transmitting, by said UE, said sensing signal, wherein said received sensing signal is a reflection of said transmitted sensing signal, receiving, by said UE, a sensing signal, determining, by said UE, that a quality of said received sensing signal is degrading. In the above example scenarios described with regard to FIGURE 2, 3, 4, and 5, SSt may refer to a sensing signal (SS) transmitted by Celli or UE2 or by UE1 itself (in mono-static scenario) and SSr may refer to a sensing signal received or expected to be received by UE1. The SS may be a reference signal e.g., any physical signal, SSB, CSI-RS, PRS, etc.

[0077] In particular examples, UE1 may be configured to perform both communication operation and sensing operation on the same carrier frequency (e.g., F1) but different set of radio resources, which can be separated in time domain and / or in the frequency domain. UE1 is further configured by Celli or autonomously (e.g., in or out of network coverage) with sensing signal resources (e.g., reference signals) on a carrier frequency for performing radio link procedures for sensing operation such as, for example, link recovery procedure such as sensing beam selection, sensing beam failure detection, candidate sensing beam detection, etc.

[0078] The carrier frequency on which the UE is configured to receive signals (e.g., CS such as PDSCH, SSB, CSI-RS, etc. and SS) may belong to certain frequency range (FR). Examples of FR are frequency range #1 (FR1), frequency range #2 (FR2), frequency range #3 (FR3) etc. In one example, frequencies within FR2 are frequencies above a certain threshold such as, for example, 24 GHz or higher. In another example, the frequencies in FR2 may vary between 24 GHz to 52.6 GHz. In another example frequencies in FR2 may vary between 24 GHz to 71 GHz. Frequencies in FR1 are below the frequencies in FR2. In one example, frequencies in FR1 range between 410 MHz and 7125 MHz.

[0079] Method in UE1 of adapting communication operational mode based on impact of sensing

[0080] According to certain examples, a UE1 operating in any of the example scenarios described above uses sensing to detect if there is any degradation of the ongoing communication service and adapts the mode of operation for performing the communication procedure if the communication quality is determined to be degraded based on the sensing procedure.

[0081] More specifically, according to various particular embodiments, the UE1 may performs at least one of the following when adapting the mode of operation: determining the impact on the performance of the communication procedure based on the sensing procedure; adapting the mode of operation (or simply operational mode) for performing the communication procedure based on the impact determined by the sensing procedure on the performance of the communication procedure; and using the adapted operational mode for performing the communication procedure.

[0082] Examples of the operational modes are wireless access network (WAN) mode (which is also called as llu mode), sidelink (SL) mode, SL relay mode, WAN relay node etc. Examples of SL relay mode are UE to network (U2N) relay, UE to UE (U2U) SL relay, etc.

[0083] Examples of communication procedure or operation performed by UE1 are UE1 receiving a communication signal (CS) from Celli or from UE2, UE1 transmitting a CS to Celli or to UE2, etc.

[0084] The reception and / or the transmission of the SS may further comprise performing a sensing measurement on the SS. Examples of the sensing measurements are signal strength, signal quality, receive timing or time of arrival of the SS, difference between the reception and transmission timing of the SS, angle of arrival of the SS etc.

[0085] In a particular example, UE1 is configured by NN1 (e.g., via RRC) with a set of CS radio resources (e.g., PDSCH, PDCCH, PSSCH, PSCCH, RS such as SSB, CSI-RS etc.) for performing the communication procedure / operation on WAN or on SL interface (e.g., when UE1 and UE2 are engaged in SL communication). In this scenario, UE1 is further configured by NN1 (e.g., via RRC) with a set of SS radio resources (e.g., RS such as another SSB, CSI-RS, etc.) for performing the sensing procedure / operation on WAN or on SL interface.

[0086] In another particular example, UE1 autonomously determines a set of CS radio resources for performing the communication purpose / operation on SL (e.g., when UE1 and UE2 are engaged in SL communication using SL mode 2 operation). In one example, at least UE1 may be out of network coverage. In this scenario, UE1 also autonomously determines a set of SS radio resources for performing the sensing procedure / operation on WAN or on SL interface. The autonomous determination of the set of CS radio resources can also be based on pre-configured information such as, for example, stored on SIM / USIM / eSIM card, etc. A term second radio node (Node2) used herein after may refer to a network node (e.g. NN1) or a UE (e.g. UE2) with which UE1 is operating at least the CS for the communication procedure.

[0087] The above steps are described below with examples:

[0088] Determining impact on communication performance based on the sensing

[0089] In this step, UE1 uses sensing procedure to determine the performance of the ongoing communication procedure. In one example, the performance of the communication procedure can be degraded due to partial or full obstruction of the CS between UE1 and Node2 (e.g., Celli or UE2) caused by one or more objects (e.g., vehicle, drone, etc.). For example, the object (01) may obstruct the CS due to relative movement / motion of UE1 with regard to 01 . The obstruction may partially or fully block LOS path and / or one or more NLOS paths of the CS between UE1 and Node2. This in turn degrades the signal quality. The core idea is that UE1 uses the sensing procedure to proactively determine if one or more objects are impacting or going to impact the quality of the ongoing communication procedure.

[0090] In a particular example, UE1 is triggered to determine the impact of one or more objects using sensing procedure on the performance of the ongoing communication procedure based on or more of the following exemplary mechanisms:

[0091] In one example, UE1 periodically determines the impact on the communication performance using the sensing procedure. The periodicity can be autonomously determined by UE1 or it can be configured by Node2.

[0092] In another example, UE1 is triggered to determine the impact on the communication performance using the sensing procedure based on the characteristic of the object. Examples of one or more parameters defining characteristic of the object are physical properties (e.g. physical size of the object such as volume, surface area, morphology / shape of the object such as spherical, cubical, etc.), type of object (e.g. human, animal, vehicle, etc.). For example, UE1 starts determining the impact on the communication performance if the object is large enough (e.g. object’s 2-dimensional area is above certain threshold, object’s height is above certain threshold, etc.).

[0093] In another example, UE1 is triggered to determine the impact on the communication performance using the sensing procedure based on the mobility of the object. The mobility profile of the object e.g. direction of movement of the object, relative movement between the object and UE1 etc. For example, UE1 starts determining the impact on the communication performance if the object and / or UE1 starts moving or starts moving with speed above certain threshold. In another example, UE1 starts determining the impact on the communication performance if the object starts moving towards UE1.

[0094] In another example, UE1 determines the impact on the communication performance based on the sensing procedure when the communication quality is degraded. The communication quality can be determined, estimated or defined by UE1 based one or more performance metrics. Examples of such metric are: user throughput / bit rate, packet transmission delay, signal quality (e.g. SNR, SINR, etc.), BLER etc. The one or more performance metrics may further be estimated as average, maximum / peak, minimum / lowest, xth percentile, etc. For example, the communication quality is assumed to be degraded if the user throughput estimated over certain time period falls below certain threshold; otherwise the communication quality is assumed to be acceptable (not degraded). In another example, the communication quality is assumed to be degraded if the signal quality estimated over certain time period falls below certain threshold(not degraded); otherwise the communication quality is assumed to be acceptable. In another example, the communication quality is assumed to be degraded if the BLER estimated over certain time period is above certain threshold; otherwise the communication quality is assumed to be acceptable (not degraded).

[0095] According to other examples, UE1 uses at least one or more sensing measurements performed by UE1 on SS to determine the impact of one or more objects on the communication performance. This is explained with examples below:

[0096] In an example, UE1 determines the impact on the communication quality based on the approximate location of the object (01). The 01’s approximate geographical location is determined based on one or more measurements performed by UE1 on the SS such as, for example, round trip time (in case of mono-static sensing), angle of arrival (AoA) of the SS, etc. For example, if 01 is physically located close to UE2 (used for SL communication) then UE1 may assume that 01 is degrading or is going to degrade the SL communication quality. In another example, if 01 is physically located close to NN1 (used for WAN communication) then UE1 may assume that 01 is degrading or is going to degrade the WAN communication quality. The object, 01 and Node2 are assumed to be physically located close to each other if their physical position is within certain region or area, which can be 1 , 2 or 3-dimensional in Euclidean space.

[0097] In another example, UE1 determines the impact on the communication quality based on the approximate location of 01 and size of 01. For example, if 01 is physically located close to Node2 (e.g., NN1 or UE2) and 01 size (e.g. volume, surface area, height / length, etc.) is larger than certain threshold then UE1 assumes that 01 is degrading or is going to degrade the communication quality.

[0098] In another example, UE1 determines the impact on the communication quality based on at least the estimated / measured AoA of the SS received at UE1. The estimated AoA depends on the extent to which the SS transmitted by UE1 is reflected or deflected by 01. The impact on the communication quality based on the estimated AoA is described with examples below.

[0099] In one example, if the estimated AoA of the SS is within certain angular range in which UE1 also operates communication signals then UE1 determines that the communication quality is degraded or is going to be degraded by 01. The angular range may be expressed in terms of one or more of: a range of angles in azimuth plane and a range of angles in zenith / vertical plane. For example, UE1 may determine the angular range based on the power level of the paths of the OS received from Node2. For example, within the applicable angular range UE1 can receive paths of OS whose received power level relative to maximum received power level is larger than or equal to certain threshold e.g., -3 dB.

[0100] In another example, if the estimated AoA of the SS at least approximately corresponds to the same direction in which Node2 is physically located then UE1 determines that the communication quality is degraded or is going to be degraded by 01. It is assumed that UE1 has knowledge about the location of Node2 e.g. based on one or more UE1 autonomous determination, historical data, information received from Node2 etc. Since 01 is located in the same direction as that of Node2 with regard to UE1 , therefore the OS operating between UE1 and Node2 is significantly attenuated or deflected by 01.

[0101] In another example, UE1 further estimates the AoAc of the OS received from Node2 and compares it with the estimated AoAs of the received SS at UE1 . If the magnitude of the difference between AoAc and AoAs is within certain threshold then UE1 assumes that at least 01 is obstructing or is going to obstruct the CS and thereby degrading or is going to degrade the communication quality. Otherwise, UE1 assumes that at least 01 is not degrading or is not going to degrade the communication quality.

[0102] The above examples are used by UE1 to proactively determine the primary cause of the communication quality i.e. due to object’s obstruction. UE1 upon determining based on the sensing procedure (in above examples) that the communication quality is or is going to be degraded, may further explicitly estimate the performance of the communication quality using one or more metrics (e.g., user throughput / bit rate, signal quality, BLER, etc.) as described earlier. This is to ascertain whether the communication quality is actually degraded or is going to be degraded (e.g., gradual decline). For example, the communication quality is assumed to be degraded if the signal quality (e.g., SNR, SINR, etc.) of the CS is below certain threshold; otherwise the signal quality is assumed to be not degraded.

[0103] Adapting Communication Operational Mode Based On Impact Determined By Sensing In this step, UE1 adapts the operational mode for performing the communication procedure based on at least the impact on the communication performance determined by the sensing procedure (as described in the previous step). The adaptation of the operational mode comprises UE1 changing or switching the operational mode for performing the communication procedure. UE1 changes or switches the operational mode of the communication procedure if UE1 has determined based on the sensing procedure that the communication quality is degraded or is going to be degraded (e.g., below an acceptable limit / threshold as identified in the previous step).

[0104] According to certain examples, UE1 switches between the operational modes according to one or more rules upon determining based on the sensing procedure that the communication quality is degraded or is going to be degraded. The rules can be pre-defined or UE1 can be configured with the rules by receiving a message (e.g., DCI, MAC-CE, RRC messages etc.) from another node (e.g., Node2). The rules enable UE1 to determine the target operational mode to be used after the switching in different network configuration scenarios in which UE1 is operating.

[0105] In a particular example, the rules may further provide information about one or more parameters required by UE1 to switch to another operational modes. The information may comprise identifiers of the nodes / devices which can serve as relay and are available in the vicinity of UE1 such as, for example, UE ID, network node relay ID, etc. Another example of the information may comprise radio resources which UE1 can use to access or establish the connection with the nodes / devices which can serve as relay and are available in the vicinity of UE1 e.g., resource blocks, carrier frequency (e.g. ARFCN), RACH resources, etc. Some specific examples of the rules are described below with regard to FIGURES 6 and 7.

[0106] In one example of the rule, UE1 performing communication using WAN with the serving cell (e.g. Celli) upon determining based on the sensing procedure that the communication quality is degraded or is going to be degraded, switches to a relay based operational mode. Examples of the relay based operational mode are network relay connected to the serving cell (e.g. Celli), UE relay connected to the serving cell (e.g. Celli) etc. This is explained below with a specific example illustrated in FIGURE 6.

[0107] FIGURE 6 illustrates UE1 switching its operational mode for communication procedure from WAN to SL to maintain communication with regard to Celli and to meet the target QoS, according to certain embodiments. Specifically, in the illustrated scenario of FIGURE 6, UE1 is performing bi-static sensing with regard to Celli to detect the object (01) based on the sensing signals (SS) and performing communication with regard to Celli based on the communication signals (CS). However, as shown in FIGURE 6(A), the obstruction caused by 01 severely attenuates the CS or even prevents the reception of the CS at UE1 . This in turn severely degrades or even blocks the ongoing communication between UE1 and Celli over the WAN link. As shown in FIGURE 6(B), based on one of the rules, UE1 establishes a UE to network (U2N) relay connection with regard to Celli via a third UE (UE3). UE3 is capable of U2N relay and is not obstructed by 01 in the directions with regard to Celli and UE1. Therefore, UE3 can relay the communication signals between Celli and UE1. This in turn allows UE1 to maintain the communication link with Celli without any service degradation. UE1 may obtain information about UE3 availability as U2N relay based on one or more of pre-configured information (e.g., by retrieving from SIM / USIM card), by receiving information from Celli via signaling, historical data / past statistics etc. The above description also applies to the scenario in which UE1 is performing mono-static sensing and performing communication with regard to Celli . The operations described in the example illustrated in FIGURE 6 also apply to the scenario in which UE1 is performing bi-static sensing and performing communication with regard to UE2.

[0108] The operations described in the illustrated in FIGURE 6 also apply to the scenario in which UE1 is performing mono-static or bi-static sensing, performing communication with regard to UE2 and switches to network node-based (fixed) relay to maintain communication with regard to Celli . In this case, UE3 can be replaced with the network node-based (fixed) relay.

[0109] In another example of the rule, UE1 performing communication using SL with another UE (e.g., UE2) upon determining based on the sensing procedure that the communication quality is degraded or is going to be degraded, switches to a UE relay based operational mode or network-based relay mode if this is possible / available. This is explained below with a specific example illustrated in FIGURE 7.

[0110] FIGURE 7 illustrates UE1 switching its operational mode for communication procedure from direct SL path to UE to UE (U2U) SL relay via UE4 to maintain communication with regard to UE2 and to meet the target QoS, according to certain embodiments. In FIGURE 7, UE1 is performing mono-static sensing to detect 01 based on SS and performing communication with regard to UE2 based on CS. However, as shown in FIGURE 7(A), the obstruction caused by 01 severely attenuates the CS or even prevents the reception of the CS at UE1 . This in turn severely degrades or even blocks the ongoing communication between UE1 and UE2 over the SL. As shown in FIGURE 7(B), based on one of the rules, UE1 establishes a UE to UE (U2U) relay connection with regard to UE2 via a fourth UE (UE4). UE4 is capable of U2U relay and is not obstructed by 01 in the directions with regard to UE1 and UE2. Therefore, UE4 can relay the communication signals between UE1 and UE2. This in turn allows UE1 to maintain the communication link with UE2 without any service degradation. UE1 may obtain information about UE4 availability as U2U relay based on one or more of pre-configured information (e.g., by retrieving from SIM / USIM card), by receiving information from another node (e.g., UE2, last serving cell, etc.) via signaling, historical data / past statistics, etc. The operations described in the example illustrated in FIGURE 7 also apply to the scenario in which UE1 is performing bi-static sensing and performing communication with regard to UE2.

[0111] The operations described in the example illustrated in FIGURE 7 also apply to the scenario in which UE1 is performing mono-static or bi-static sensing, performing communication with regard to UE2 and switches to network-based connection (e.g., Cell2) to maintain communication with regard to UE2 (if network connection is possible). In this case, UE4 can be replaced with the network node such as, for example, NN2 serving Cell2. For example, UE1 and UE2 may be out of network coverage on certain carrier frequency (e.g., F1) but can establish communication via Cell2 on another carrier frequency / band (e.g., F2).

[0112] Using Adapted Operational Mode for Performing Communication Procedure.

[0113] According to certain examples, after adapting the operational mode (e.g., switching to a new / target mode), UE1 starts performing communication procedure using the new operational mode. UE1 may continue using the new operational mode for the communication purpose until the communication session is completed or until the communication quality is again degraded below the acceptable limit. In the latter case, UE2 may again change its operational mode for maintaining the communication according to the same rules as described in the previous section.

[0114] Method In Network Node Configuring UE1 for Switching Operational Mode Based on Impact of Sensing

[0115] A method is provided by a NN1 serving or managing Celli , which in turn is serving UE1 operating in any of the scenarios described above. According to certain embodiments, for example, the method by the NN1 includes:

[0116] - configuring UE1 with information (e.g., via signaling message) about one or more rules for enabling UE1 to switch between operational modes when the communication quality is degraded as determined by UE1 based on the sensing procedure;

[0117] - Continuing operating CS with regard to UE1 using the target / new operational mode used by UE1 after UE1 has switched to the target / new operational mode. The information provided by NN1 to UE1 may further comprise identifiers of the operational modes which can be used by the UE, parameters related to the node such as node IDs (e.g., IDs of relay nodes such as U2U relay, U2N relay, fixed relay, cell, etc.), set of radio resources (e.g., RBs, RACH resources, etc.) for enabling UE1 to access / establish communication with the target node after the operational mode switching etc.

[0118] FIGURE 8 shows a UE QQ200 in accordance with some embodiments.

[0119] As used herein, a UE refers to a device capable, configured, arranged and / or operable to communicate wirelessly with network nodes and / or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless cameras, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehiclemounted or vehicle embedded / integrated wireless device, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3GPP), including a narrow band internet of things (NB-loT) UE, a machine type communication (MTC) UE, and / or an enhanced MTC (eMTC) UE.

[0120] The UE may be arranged for switching operational modes in a communication link between said UE and a node, wherein said operational modes specify how said UE and said node communicate, said UE comprising processing circuitry arranged for: communicating with said node using a first operational mode; performing sensing for determining degradation of quality of said communication link between said UE and said node while using the first operational mode switching from said first operational mode to a second operational mode, different to said first operational mode, based on said determined degradation, for maintaining said communication link between said UE and said node

[0121] The UE may support device-to-device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to- infrastructure (V2I), or vehicle-to-everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and / or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).

[0122] The UE QQ200 includes processing circuitry QQ202 that is operatively coupled via a bus QQ204 to an input / output interface QQ206, a power source QQ208, a memory QQ210, a communication interface QQ212, and / or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in FIGURE 9. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

[0123] The processing circuitry QQ202 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory QQ210. The processing circuitry QQ202 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general-purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry QQ202 may include multiple central processing units (CPUs).

[0124] In the description above, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of implementations of the disclosed technology. It will be apparent, however, to one skilled in the art that embodiments of the disclosed technology may be practiced without some of these specific details. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope thereof.

Claims

CLAIMS1. A method performed by a User Equipment, UE, of switching operational modes in a communication link between said UE and a node, wherein said operational modes specify how said UE and said node communicate, said method comprising the steps of: communicating, by said UE, with said node using a first operational mode; performing, by said UE, sensing for determining degradation of quality of said communication link between said UE and said node while using the first operational mode switching, by said UE, from said first operational mode to a second operational mode, different to said first operational mode, based on said determined degradation, for maintaining said communication link between said UE and said node.

2. A method in accordance with claim 1 , wherein said operational modes are any of: direct sidelink, SLUE-to-Network, U2N,Wide Area Network, WAN, UE-to-Network, U2N, relay, or UE-to-UE, U2U, Sidelink relay.

3. A method in accordance with any of the previous claims, wherein said step of performing said sensing comprises: performing, by said UE, said sensing using radio resources other than radio resources used for communication using said first operational mode.

4. A method in accordance with claim 3, wherein said step of performing said sensing comprises any of:performing, by said UE, said sensing using a frequency spectrum different to a frequency spectrum used for communication using said first operational mode performing, by said UE, said sensing in time instances different to a time instances used for communication using said first operational mode.

5. A method in accordance with any of the previous claims, wherein said step of performing said sensing comprises: receiving, by said UE, a sensing signal; determining, by said UE, that a quality of said received sensing signal is degrading.

6. A method in accordance with claim 5, wherein said step of performing said sensing further comprises: transmitting, by said UE, said sensing signal, wherein said received sensing signal is a reflection of said transmitted sensing signal.

7. A method in accordance with any of the previous claims, wherein said node is a base station in a telecommunication network.

8. A method in accordance with any of the claims 1 - 6, wherein said node is a further User Equipment, UE.

9. A method in accordance with any of the previous claims, wherein said step of performing said sensing is performed using any of: periodically; triggered by an event.

10. A method in accordance with any of the previous claims, wherein said step of performing said sensing comprises: estimating, by said UE, that said quality of said communication link falls below a predefined threshold.

11. A User Equipment, UE, arranged for switching operational modes in a communication link between said UE and a node, wherein said operational modes specify how said UE and said node communicate, said UE comprising processing circuitry arranged for: communicating with said node using a first operational mode; performing sensing for determining degradation of quality of said communication link between said UE and said node while using the first operational mode switching from said first operational mode to a second operational mode, different to said first operational mode, based on said determined degradation, for maintaining said communication link between said UE and said node.

12. A UE in accordance with clam 11 , wherein said operational modes are any of: direct sidelink, SLUE-to-Network, U2N,Wide Area Network, WAN, UE-to-Network, U2N, relay, or UE-to-UE, U2U, Sidelink relay.

13. A UE in accordance with any of the claims 11 - 12, wherein said processing circuitry is further arranged for: performing, by said UE, said sensing using radio resources other than radio resources used for communication using said first operational mode.

14. A UE in accordance with claim 13, wherein said processing circuitry is further arranged for any of: performing said sensing using a frequency spectrum different to a frequency spectrum used for communication using said first operational mode performing said sensing in time instances different to a time instances used for communication using said first operational mode.

15. A UE in accordance with any of the claims 11 - 14, wherein said processing circuitry is further arranged for: receiving, by said UE, a sensing signal; determining, by said UE, that a quality of said received sensing signal is degrading.

16. A UE in accordance with any of the claims 11 - 15, wherein said processing circuitry is further arranged for: transmitting said sensing signal, wherein said received sensing signal is a reflection of said transmitted sensing signal.

17. A UE in accordance with any of the claims 11 - 16, wherein said node is a base station in a telecommunication network.

18. A UE in accordance with any of the claims 11 - 17, wherein said node is a further User Equipment, UE.

19. A UE in accordance with any of the claims 11 - 18, wherein said processing circuitry is further arranged for performing said sensing using any of: periodically; triggered by an event.

20. A UE in accordance with any of the claims 11 - 19, wherein said processing circuitry is further arranged for performing said sensing comprising: estimating, by said UE, that said quality of said communication link falls below a predefined threshold.

21. A computer program product comprising a computer readable medium having instructions stored thereon which, when executed by a User Equipment, UE, cause said UE to implement a method in accordance with any of the claims 1 - 10.

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