EP4631308A1

EP4631308A1 - Method and apparatus for relay communication

Info

Publication number: EP4631308A1
Application number: EP23825403.1A
Authority: EP
Inventors: Zhang Zhang; Jan Christoffersson; Min Wang
Original assignee: Telefonaktiebolaget LM Ericsson AB
Current assignee: Telefonaktiebolaget LM Ericsson AB
Priority date: 2022-12-09
Filing date: 2023-12-08
Publication date: 2025-10-15
Also published as: WO2024121402A1

Abstract

Various embodiments of the present disclosure provide a method for relay communication. The method which may be performed by a first terminal device comprises determining pairing information of the first terminal device. The pairing information may be related to one or more devices which are relaying capable devices paired to the first terminal device. The one or more devices may include at least a second terminal device. In accordance with an exemplary embodiment, the method further comprises transmitting at least part of the pairing information of the first terminal device towards a network node.

Description

METHOD AND APPARATUS FOR RELAY COMMUNICATION

FIELD OF THE INVENTION

The present disclosure generally relates to communication networks, and more specifically, to a method and apparatus for relay communication.

BACKGROUND

This section introduces aspects that may facilitate a better understanding of the disclosure. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.

Communication service providers and network operators have been continually facing challenges to deliver value and convenience to consumers by, for example, providing compelling network services and performance. With the evolution of wireless communication, a requirement for supporting device-to-device (D2D) communication features in various applications is proposed. An extension for the D2D work may consist of supporting vehicle-to-everything (V2X) communication, which may include any combination of direct communications among vehicles, pedestrians and infrastructure. Wireless communication networks such as fourth generation (4G)/long term evolution (LTE) and fifth generation (5G)/new radio (NR) networks may be expected to use V2X services and support communication for V2X capable user equipment (UE).

SUMMARY

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

D2D communications (also referred to as sidelink (SL) communications or communications over PC5 interface) between neighboring devices are specified by the 3rd generation partnership project (3GPP) in Release-12 (Rel-12). Some enhancements of the SL are introduced in subsequent releases for vehicle-to-vehicle (V2V) or V2X communications. For a remote UE in the network (NW), e.g., a UE that may be out of cell coverage and may not be able to connect with a network node directly, a UE-to- NW relay UE (also called U2N relay for short) may provide the functionality to support connectivity to the NW for the remote UE. In this case, uplink/downlink (UL/DL) traffics of the remote UE may be forwarded by the U2N relay. In some cases, the remote UE may communicate with another UE via one or more UE-to-UE relay UEs (also called U2U relays for short), and various traffics of the remote UE may be forwarded by the one or more U2U relays.

Since multipath communication may bring an improvement on transmission reliability and network throughput, it may be an attractive option to apply multipath communication in a network, so that a remote UE may be connected to the network via one direct path and at least one indirect path. For example, an indirect path between a remote UE and a network may be established via a Layer 2 UE-to-NW relay or via another UE which may act as a relay UE. For the latter relaying scenario, the UE-UE inter-connection (also called inter UE connection in this document) is assumed to be ideal and the pairing relationship between the remote UE and the relay UE is preconfigured or static, therefore there is no need for the remote/relay UE to perform some operations such as link measurement and discovery. However, the network may still need to know information on the paired relay/remote UE to facilitate relaying configuration. Therefore, it may be desirable to implement exchange and report of information on the paired relay/remote UE in a more efficient way. Various exemplary embodiments of the present disclosure propose a solution for relay communication, which may enable a remote UE and a relay UE to properly exchange and report information of the paired remote/relay UE, e.g., when the inter UE connection is ideal and may use non-3GPP based technique.

It can be appreciated that the “remote UE” described in this document may refer to a UE that may communicate with a relay UE e.g., via PC5/SL interface, and/or communicate with a network node e.g., via Uu interface. As an example, the remote UE may be a 5G proximity-based services (ProSe) enabled UE that may communicate with a data network (DN) via a ProSe 5G UE-to-NW relay UE. As another example, the remote UE may be a 5G ProSe enabled UE that may communicate with another UE via a ProSe 5G UE-to-UE relay UE.

It can be appreciated that the “relay UE” described in this document may refer to the “UE-to-NW relay UE” in a UE-to-NW relay scenario or the “UE-to-UE relay UE” in a UE-to-UE relay scenario. As an example, the relay UE may be a 5G ProSe enabled UE that is capable of supporting connectivity to the NW and/or other UE(s) for the remote UE.

It can be appreciated that the “UE-to-Network relay UE” described in this document may also be referred to as “UE-to-NW relay UE”, “UE-to-Network relay” and “UE-to- NW relay”. Thus, the terms “UE-to-Network relay UE”, “UE-to-NW relay UE”, “UE- to-Network relay” and “UE-to-NW relay” may be used interchangeably in this document.

According to a first aspect of the present disclosure, there is provided a method performed by a first terminal device (e.g., a remote UE, etc.). The method comprises: determining pairing information of the first terminal device. The pairing information may be related to one or more devices which are relaying capable devices paired to the first terminal device. The one or more devices may include at least a second terminal device. In accordance with an exemplary embodiment, the method further comprises: transmitting at least part of the pairing information of the first terminal device towards a network node.

In accordance with an exemplary embodiment, the pairing information of the first terminal device may indicate one or more of: a number of the one or more devices; one or more identifiers of the one or more devices; and one or more serving cells of the one or more devices.

In accordance with an exemplary embodiment, the one or more identifiers of the one or more devices may include one or more of: one or more Uu identifiers of the one or more devices; one or more temporary identifiers of the one or more devices; and one or more local identifiers of the one or more devices.

In accordance with an exemplary embodiment, the one or more temporary identifiers and/or the one or more local identifiers of the one or more devices may be allocated by the first terminal device.

In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: informing an identifier of the first terminal device and/or an identifier of the second terminal device to the second terminal device.

In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: receiving information indicating an identifier of the second terminal device and/or a serving cell of the second terminal device from the second terminal device.

In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: receiving, from the network node, configuration information for enabling or disabling at least partial reporting of the pairing information of the first terminal device towards the network node.

In accordance with an exemplary embodiment, the configuration information may be based at least in part on one or more the following factors: a demand of the network node; a state of a connection between the first terminal device and the network node; a state of connections between the one or more devices and the network node; link quality over Uu interface of an indirect path configured to the first terminal device; and link quality over Uu interface between the one or more devices and the network node.

In accordance with an exemplary embodiment, the transmission of the at least part of the pairing information of the first terminal device towards the network node may be enabled or disabled based at least in part on one or more the following factors: configuration information from the network node; a change of information about the one or more devices; capabilities of the one or more devices to perform relaying to the network node for the first terminal device; and a result of cell selection or reselection of the one or more devices.

In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: receiving, from the second terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: transmitting, towards the network node, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: transmitting, to the second terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device.

In accordance with an exemplary embodiment, the set of the candidate cells may include one or more of: a serving cell of the first terminal device; and one or more cells indicated by the network node.

In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: receiving, from the second terminal device, information indicating whether the second terminal device selects a cell from the set of the candidate cells.

In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: transmitting, towards the network node, information indicating whether the second terminal device selects a cell from the set of the candidate cells.

In accordance with an exemplary embodiment, the method according to the first aspect of the present disclosure may further comprise: establishing an indirect path between the first terminal and the network node via a relay device. In an embodiment, the relay device may be selected from the one or more devices by the network node, according to the at least part of the pairing information of the first terminal device and/or information reported to the network node by at least one of the one or more devices paired to the first terminal device.

According to a second aspect of the present disclosure, there is provided an apparatus which may be implemented as a first terminal device. The apparatus may comprise one or more processors and one or more memories storing computer program codes. The one or more memories and the computer program codes may be configured to, with the one or more processors, cause the apparatus at least to perform any step of the method according to the first aspect of the present disclosure. According to a third aspect of the present disclosure, there is provided a computer- readable medium having computer program codes embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to the first aspect of the present disclosure.

According to a fourth aspect of the present disclosure, there is provided an apparatus which may be implemented as a first terminal device. In accordance with an exemplary embodiment, the first terminal device may be configured to perform any step of the method according to the first aspect of the present disclosure.

According to a fifth aspect of the present disclosure, there is provided a computer program or computer program product comprising program code to be executed by at least one processor of a first terminal device, whereby execution of the program code causes the first terminal device to perform any step of the method according to the first aspect of the present disclosure.

According to a sixth aspect of the present disclosure, there is provided a method performed by a second terminal device (e.g., a relay UE, etc.). The method comprises: determining pairing information of the second terminal device which is a relaying capable device paired to a first terminal device. The pairing information may indicate an identifier of the first terminal device and/or an identifier of the second terminal device. In accordance with an exemplary embodiment, the method according to the sixth aspect of the present disclosure further comprises: transmitting at least part of the pairing information of the second terminal device towards a network node.

In accordance with an exemplary embodiment, the method according to the sixth aspect of the present disclosure may further comprise: receiving the identifier of the first terminal device and/or the identifier of the second terminal device from the first terminal device. In accordance with an exemplary embodiment, the identifier of the first terminal device may be a Uu identifier, a temporary identifier or a local identifier of the first terminal device.

In accordance with an exemplary embodiment, the temporary identifier and/or the local identifier of the first terminal device may be allocated by the first terminal device or the network node.

In accordance with an exemplary embodiment, the identifier of the second terminal device may be a Uu identifier, a temporary identifier or a local identifier of the second terminal device.

In accordance with an exemplary embodiment, the temporary identifier and/or the local identifier of the second terminal device may be allocated by the first terminal device.

In accordance with an exemplary embodiment, the method according to the sixth aspect of the present disclosure may further comprise: transmitting information indicating the identifier of the second terminal device and/or a serving cell of the second terminal device to the first terminal device.

In accordance with an exemplary embodiment, the method according to the sixth aspect of the present disclosure may further comprise: determining whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, the method according to the sixth aspect of the present disclosure may further comprise: transmitting, to the first terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, when Uu link quality of the second terminal device is above a threshold configured by the network node, the second terminal device may determine that the second terminal device is capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, the method according to the sixth aspect of the present disclosure may further comprise: receiving, from the first terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device.

In accordance with an exemplary embodiment, the method according to the sixth aspect of the present disclosure may further comprise: determining whether to select a cell from the set of the candidate cells.

In accordance with an exemplary embodiment, the method according to the sixth aspect of the present disclosure may further comprise: transmitting, to the first terminal device, information indicating whether the second terminal device selects the cell from the set of the candidate cells.

In accordance with an exemplary embodiment, the method according to the sixth aspect of the present disclosure may further comprise: receiving a paging message from the network node. The paging message may instruct the second terminal device to report one or more Uu quality measurements of the second terminal device.

In accordance with an exemplary embodiment, the paging message may include one or more of: an identifier of the first terminal device; an identifier of the second terminal device; information indicating that the paging message is for Uu quality reporting only; and information about a list of cells for which Uu quality measurements need to be reported.

In accordance with an exemplary embodiment, the second terminal device may transmit one or more of the following information towards the network node in a small data transmission (SDT) procedure: the at least part of the pairing information of the second terminal device; and one or more Uu quality measurements of the second terminal device.

According to a seventh aspect of the present disclosure, there is provided an apparatus which may be implemented as a second terminal device. The apparatus may comprise one or more processors and one or more memories storing computer program codes. The one or more memories and the computer program codes may be configured to, with the one or more processors, cause the apparatus at least to perform any step of the method according to the sixth aspect of the present disclosure.

According to an eighth aspect of the present disclosure, there is provided a computer- readable medium having computer program codes embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to the sixth aspect of the present disclosure.

According to a ninth aspect of the present disclosure, there is provided an apparatus which may be implemented as a second terminal device. In accordance with an exemplary embodiment, the second terminal device may be configured to perform any step of the method according to the sixth aspect of the present disclosure.

According to a tenth aspect of the present disclosure, there is provided a computer program or computer program product comprising program code to be executed by at least one processor of a second terminal device, whereby execution of the program code causes the second terminal device to perform any step of the method according to the sixth aspect of the present disclosure. According to a eleventh aspect of the present disclosure, there is provided a method performed by a second terminal device (e.g., a relay UE, etc.). The method comprises: determining pairing information of the second terminal device which is a relaying capable device paired to a first terminal device. The pairing information may indicate an identifier of the first terminal device and/or an identifier of the second terminal device. In accordance with an exemplary embodiment, the method according to the eleventh aspect of the present disclosure further comprises: transmitting at least part of the pairing information of the second terminal device towards a network node.

In accordance with an exemplary embodiment, the method according to the eleventh aspect of the present disclosure may further comprise: receiving the identifier of the first terminal device and/or the identifier of the second terminal device from the first terminal device.

In accordance with an exemplary embodiment, the identifier of the first terminal device may be a Uu identifier, a temporary identifier or a local identifier of the first terminal device.

In accordance with an exemplary embodiment, the method according to the eleventh aspect of the present disclosure may further comprise: transmitting information indicating the identifier of the second terminal device and/or a serving cell of the second terminal device to the first terminal device.

In accordance with an exemplary embodiment, the method according to the eleventh aspect of the present disclosure may further comprise: determining whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, the method according to the eleventh aspect of the present disclosure may further comprise: transmitting, to the first terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, the method according to the eleventh aspect of the present disclosure may further comprise: receiving, from the first terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device.

In accordance with an exemplary embodiment, the method according to the eleventh aspect of the present disclosure may further comprise: determining whether to select a cell from the set of the candidate cells. In accordance with an exemplary embodiment, the method according to the eleventh aspect of the present disclosure may further comprise: transmitting, to the first terminal device, information indicating whether the second terminal device selects the cell from the set of the candidate cells.

In accordance with an exemplary embodiment, the method according to the eleventh aspect of the present disclosure may further comprise: receiving a paging message from the network node. The paging message may instruct the second terminal device to report one or more Uu quality measurements of the second terminal device.

According to a twelfth aspect of the present disclosure, there is provided an apparatus which may be implemented as a second terminal device. The apparatus may comprise one or more processors and one or more memories storing computer program codes. The one or more memories and the computer program codes may be configured to, with the one or more processors, cause the apparatus at least to perform any step of the method according to the sixth aspect of the present disclosure.

According to an thirteenth aspect of the present disclosure, there is provided a computer-readable medium having computer program codes embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to the sixth aspect of the present disclosure.

According to a fourteenth aspect of the present disclosure, there is provided an apparatus which may be implemented as a second terminal device. In accordance with an exemplary embodiment, the second terminal device may be configured to perform any step of the method according to the sixth aspect of the present disclosure.

According to a fifteenth aspect of the present disclosure, there is provided a computer program or computer program product comprising program code to be executed by at least one processor of a second terminal device, whereby execution of the program code causes the second terminal device to perform any step of the method according to the sixth aspect of the present disclosure.

According to an sixteenth aspect of the present disclosure, there is provided a method performed by a network node. The method comprises: transmitting, towards a first terminal device, configuration information for enabling or disabling at least partial reporting of pairing information of the first terminal device towards the network node. The pairing information of the first terminal device may be related to one or more devices which are relaying capable devices paired to the first terminal device. The one or more devices may include at least a second terminal device. In accordance with an exemplary embodiment, the method further comprises: receiving at least part of the pairing information which is reported by the first terminal device according to the configuration information.

In accordance with an exemplary embodiment, the pairing information of the first terminal device may indicate one or more of: a number of the one or more devices; one or more identifiers of the one or more devices; and one or more serving cells of the one or more devices. In accordance with an exemplary embodiment, the one or more identifiers of the one or more devices may include one or more of: one or more Uu identifiers of the one or more devices; one or more temporary identifiers of the one or more devices; and one or more local identifiers of the one or more devices.

In accordance with an exemplary embodiment, the configuration information may be determined by the network node based at least in part on one or more the following factors: a demand of the network node; a state of a connection between the first terminal device and the network node; a state of connections between the one or more devices and the network node; link quality over Uu interface of an indirect path configured to the first terminal device; and link quality over Uu interface between the one or more devices and the network node.

In accordance with an exemplary embodiment, the at least partial reporting of the pairing information of the first terminal device towards the network node may be enabled or disabled also based at least in part on one or more the following factors: a change of information about the one or more devices; capabilities of the one or more devices to perform relaying to the network node for the first terminal device; and a result of cell selection or reselection of the one or more devices.

In accordance with an exemplary embodiment, the method according to the sixteenth aspect of the present disclosure may further comprise: receiving at least part of pairing information of the second terminal device from the second terminal device. The pairing information of the second terminal device may indicate an identifier of the first terminal device and/or an identifier of the second terminal device.

In accordance with an exemplary embodiment, the method according to the sixteenth aspect of the present disclosure may further comprise: receiving, from the first terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device. In accordance with an exemplary embodiment, when Uu link quality of the second terminal device is above a threshold configured by the network node, the second terminal device may be capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, the method according to the sixteenth aspect of the present disclosure may further comprise: receiving, from the first terminal device, information indicating whether the second terminal device selects a cell from a set of the candidate cells available for cell selection or reselection by the second terminal device.

In accordance with an exemplary embodiment, the method according to the sixteenth aspect of the present disclosure may further comprise: transmitting a paging message towards one or more relay devices paired to one or more remote devices served by the network node. The paging message may instruct the one or more relay devices to report corresponding Uu quality measurements.

In accordance with an exemplary embodiment, the paging message may include one or more of: one or more identifiers of the one or more relay devices; one or more identifiers of the one or more remote devices; information indicating that the paging message is for Uu quality reporting only; and information about a list of cells for which Uu quality measurements need to be reported.

In accordance with an exemplary embodiment, the network node may receive one or more of the following information in an SDT procedure: at least part of pairing information of the second terminal device; and one or more Uu quality measurements of the second terminal device.

In accordance with an exemplary embodiment, the method according to the sixteenth aspect of the present disclosure may further comprise: determining which of the one or more devices paired to the first terminal device is to be selected as a relay device for the first terminal device, according to the at least part of the pairing information of the first terminal device and/or information reported to the network node by at least one of the one or more devices paired to the first terminal device.

In accordance with an exemplary embodiment, the method according to the sixteenth aspect of the present disclosure may further comprise: establishing an indirect path between the first terminal and the network node via the relay device selected for the first terminal device from the one or more devices by the network node.

According to a seventeenth aspect of the present disclosure, there is provided an apparatus which may be implemented as a network node. The apparatus may comprise one or more processors and one or more memories storing computer program codes. The one or more memories and the computer program codes may be configured to, with the one or more processors, cause the apparatus at least to perform any step of the method according to the eleventh aspect of the present disclosure.

According to a eighteenth aspect of the present disclosure, there is provided a computer-readable medium having computer program codes embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to the eleventh aspect of the present disclosure.

According to a nineteenth aspect of the present disclosure, there is provided an apparatus which may be implemented as a network node. In accordance with an exemplary embodiment, the network node may be configured to perform any step of the method according to the eleventh aspect of the present disclosure. According to a twentieth aspect of the present disclosure, there is provided a computer program or computer program product comprising program code to be executed by at least one processor of a network node, whereby execution of the program code causes the network node to perform any step of the method according to the eleventh aspect of the present disclosure.

According to various exemplary embodiments, pairing information of a terminal device (e.g., a paired relay/remote UE, etc.) may be exchanged and reported with reduced signaling over e.g., the Uu interface. Based on the reported pairing information, a network node (e.g., a base station, etc.) can (re)select a proper relay UE for a remote UE. Such full control on relay UE (re)selection by the network node can enhance system performance, especially for multipath relaying with ideal inter UE connection.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure itself, the preferable mode of use and further objectives are best understood by reference to the following detailed description of the embodiments when read in conjunction with the accompanying drawings, in which:

Fig.l is a diagram illustrating an exemplary signaling flow for information exchange according to an embodiment of the present disclosure;

Figs.2-5 are flowcharts illustrating various methods according to some embodiments of the present disclosure;

Fig.6 is a block diagram illustrating an apparatus according to an embodiment of the present disclosure;

Figs.7A-7C are block diagrams illustrating various apparatuses according to some embodiments of the present disclosure; Fig.8 shows an example of a communication system in accordance with some embodiments;

Fig.9 is a block diagram of a host, which may be an embodiment of the host of Fig.8, in accordance with various aspects described herein; and

Fig.10 shows a communication diagram of a host communicating via a network node with a UE over a partially wireless connection in accordance with some embodiments.

DETAILED DESCRIPTION

The embodiments of the present disclosure are described in detail with reference to the accompanying drawings. It should be understood that these embodiments are discussed only for the purpose of enabling those skilled persons in the art to better understand and thus implement the present disclosure, rather than suggesting any limitations on the scope of the present disclosure. Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present disclosure should be or are in any single embodiment of the disclosure. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present disclosure. Furthermore, the described features, advantages, and characteristics of the disclosure may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize that the disclosure may be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the disclosure.

As used herein, the term “communication network” refers to a network following any suitable communication standards, such as new radio (NR), long term evolution (LTE), LTE-Advanced, wideband code division multiple access (WCDMA), high-speed packet access (HSPA), and so on. Furthermore, the communications between a terminal device and a network node in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1G), the second generation (2G), 2.5G, 2.75G, the third generation (3G), 4G, 4.5G, 5G communication protocols, and/or any other protocols either currently known or to be developed in the future.

The term “network node” refers to a network device in a communication network via which a terminal device accesses to the network and receives services therefrom. The network node may refer to a base station (BS), an access point (AP), a multi - cell/multicast coordination entity (MCE), a controller or any other suitable device in a wireless communication network. The BS may be, for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), a next generation NodeB (gNodeB or gNB), a remote radio unit (RRU), a radio header (RH), a remote radio head (RRH), a relay, a low power node such as a femto, a pico, and so forth.

Yet further examples of the network node comprise multi-standard radio (MSR) radio equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, positioning nodes and/or the like. More generally, however, the network node may represent any suitable device (or group of devices) capable, configured, arranged, and/or operable to enable and/or provide a terminal device access to a wireless communication network or to provide some service to a terminal device that has accessed to the wireless communication network.

The term “terminal device” refers to any end device that can access a communication network and receive services therefrom. By way of example and not limitation, the terminal device may refer to a mobile terminal, a user equipment (UE), or other suitable devices. The UE may be, for example, a subscriber station, a portable subscriber station, a mobile station (MS) or an access terminal (AT). The terminal device may include, but not limited to, portable computers, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, a mobile phone, a cellular phone, a smart phone, a tablet, a wearable device, a personal digital assistant (PDA), a vehicle, and the like.

As yet another specific example, in an Internet of things (loT) scenario, a terminal device may also be called an loT device and represent a machine or other device that performs monitoring, sensing and/or measurements etc., and transmits the results of such monitoring, sensing and/or measurements etc. to another terminal device and/or a network equipment. The terminal device may in this case be a machine-to-machine (M2M) device, which may in a 3rd generation partnership project (3 GPP) context be referred to as a machine-type communication (MTC) device.

As one particular example, the terminal device may be a UE implementing the 3 GPP narrow band Internet of things (NB-IoT) standard. Particular examples of such machines or devices are sensors, metering devices such as power meters, industrial machinery, or home or personal appliances, e.g. refrigerators, televisions, personal wearables such as watches etc. In other scenarios, a terminal device may represent a vehicle or other equipment, for example, a medical instrument that is capable of monitoring, sensing and/or reporting etc. on its operational status or other functions associated with its operation.

As used herein, the terms “first”, “second” and so forth refer to different elements. The singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises”, “comprising”, “has”, “having”, “includes” and/or “including” as used herein, specify the presence of stated features, elements, and/or components and the like, but do not preclude the presence or addition of one or more other features, elements, components and/or combinations thereof. The term “based on” is to be read as “based at least in part on”. The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment”. The term “another embodiment” is to be read as “at least one other embodiment”. Other definitions, explicit and implicit, may be included below.

Wireless communication networks are widely deployed to provide various telecommunication services such as voice, video, data, messaging and broadcasts. To meet dramatically increasing network requirements on traffic capacity and data rates, one interesting option for communication technique development is to allow D2D communications to be implemented in a wireless communication network such as 4G/LTE or 5G/NR network. As used herein, D2D may be referred to in a broader sense to include communications between any types of UEs, and include V2X communications between a vehicle UE and any other type of UE. D2D and/or V2X may be a component of many existing wireless technologies when it comes to direct communication between wireless devices. D2D and/or V2X communications as an underlay to cellular networks may be proposed as an approach to take advantage of the proximity of devices.

3GPP specifies the LTE D2D technology, also known as sidelink (SL) or the PC5 interface, as part of Release 12 (Rel-12) of LTE. The target use cases were the proximity services (communication and discovery). Support of ProSe was enhanced during Rel-13 of LTE. In Rel-14, the LTE sidelink was extensively redesigned to support vehicular communications (commonly referred to as V2X or V2V). Support of LTE V2X related enhancements targeting the specific characteristics of vehicular communications was again enhanced during Rel-15. In LTE V2X only broadcast is supported over SL. From the point of view of the lowest radio layers, the LTE SL uses broadcast communication. That is, transmission from a UE targets any receiver that is in range.

In Rel-16, 3 GPP introduced the SL for 5G NR. The driving use cases were vehicular communications with more stringent requirements than those typically served using the LTE SL. To meet these requirements, the NR SL is capable of broadcast, groupcast, and unicast communications. In groupcast communication, the intended receivers of a message are typically a subset of the vehicles near the transmitter, whereas in unicast communication, there is a single intended receiver.

Both the LTE SL and the NR SL can operate with and without network coverage and with varying degrees of interaction between UEs and the NW (network), including support for standalone, network-less operation.

In 3GPP Rel-17, national security and public safety (NSPS) is considered to be one important use case, which can benefit from the already developed NR SL features in Rel-16. Therefore, 3 GPP may specify enhancements related to NSPS use case taking NR Rel-16 SL as a baseline. Besides, in some scenarios NSPS services need to operate with partial or without NW coverage, such as indoor firefighting, forest firefighting, earthquake rescue, sea rescue, etc., where the infrastructure is (partially) destroyed or not available, therefore, coverage extension is a crucial enabler for NSPS, for both NSPS services communicated between UEs and the cellular NW and that communicated between UEs over SL. In Rel.17, a SID on NR sidelink relay (as described in 3GPP RP-193253) was launched which aims to further explore coverage extension for sidelink-based communication, including both UE-to-NW relay for cellular coverage extension and UE-to-UE relay for sidelink coverage extension. When the work proceeded to normative phase, only UE-to-NW relay is considered (as described in 3GPP RP-210893).

The concept of Layer-2 based UE-to-NW relay is described in 3GPP technical report (TR) 23.752 V2.0.0. In accordance with an exemplary embodiment, a L2 UE-to-NW relay UE may provide forwarding functionality that can relay any type of traffic over the PC5 link. For example, the L2 UE-to-NW relay UE may provide the functionality to support connectivity to the 5G system (5GS) for remote UEs.

In 3 GPP Rel-17, only path switching between direct path and indirect path is supported for Layer 2 UE-to-NW relay. During indirect to direct path switch, a serving relay worse than a threshold may be one event to trigger the measurement report sent by a remote UE, during direct to indirect path switch, a candidate relay better than a threshold may be one event to trigger the measurement report sent by the remote UE, and the measurement report may include the L2 identifier (ID) and the serving cell ID of the candidate relay(s). The measurement on the candidate relay may be based on quality measured over a discovery message.

A relay UE may be allowed to perform UE-to-NW relay discovery message transmission in case:

• its Uu reference signal received power (RSRP) to the serving cell is above a configured minimum threshold by a hysteresis and below a configured maximum threshold by a hysteresis; or

• only minimum threshold is provided and its Uu RSRP to the serving cell is above the minimum threshold by a hysteresis; or

• only maximum threshold is provided and its Uu RSRP to the serving cell is below the maximum threshold by a hysteresis.

A remote UE may be allowed to perform UE-to-NW relay discovery message transmission if its Uu RSRP to the serving cell is below a configured minimum threshold by a hysteresis or it is out of coverage.

In 3GPP Rel-18, a new WID on NR sidelink relay enhancements was launched (as described in 3GPP RP-213585). The objective is to specify solutions that are needed to enhance NR sidelink relay, including both UE-to-NW relay and UE-to-UE relay. For UE-to-NW relay, one objective is to study the benefit and potential solutions for multi-path support to enhance reliability and throughput (e.g., by switching among or utilizing the multiple paths simultaneously) in the following scenarios:

• A UE is connected to the same gNB using one direct path and one indirect path via (i) Layer 2 UE-to-NW relay, or (ii) via another UE (where the UE- UE inter-connection is assumed to be ideal), where the solutions for (i) are to be reused for (ii) without precluding the possibility of excluding a part of the solutions which is unnecessary for the operation for (ii).

For multipath relaying scenario (ii) (i.e., the UE-UE inter-connection is ideal), the following agreements have been made by 3 GPP RAN2:

• The relation between remote UE and relay UE in scenario (ii) is preconfigured or static and how the relation is pre-configured or static is out of the 3 GPP scope.

• The relay UE is restricted to serve only one remote UE in scenario (ii).

• The following cases are to be supported for scenario (ii):

The remote UE configured only on the direct path adds the indirect path under the same gNB.

The remote UE configured with multi-path releases the indirect path.

• Support primary cell (PCell) on the direct path only when the UE is in multi-path operation, for both scenario (i) and scenario (ii).

• RAN2 understand that UE identification in L2 protocol data unit (PDU) over non-3GPP (ideal) link is not in 3GPP scope in scenario (ii).

For multipath relaying scenario (ii), the UE-UE inter-connection is ideal and the pairing relationship is pre-configured or static, therefore, there may be no need for the remote UE to measure and report the quality of the UE-UE link and also no need for the remote UE or the relay UE to perform a discovery procedure to find the neighbor UEs with ideal inter UE connection. However, the remote/relay UE may still need to inform the gNB of the information on the paired relay/remote UE to assist the gNB to decide whether to add or change the indirect path. One or more of the following issues may need to be addressed correspondingly:

• When the pairing information needs to be informed to the gNB (if it may not be triggered by an event based on quality of the UE-UE link as in 3 GPP Rel-17)?

• Which UE may need to inform the pairing information to the gNB?

• What ID the remote UE may need to use for the paired relay UE over the Uu interface (In Rel-17, the L2 ID is used but this may not be used for the non-3GPP ideal link)?

Various exemplary embodiments of the present disclosure propose solutions for exchange and report of information on paired relay and remote UEs with an ideal inter UE connection. In accordance with an exemplary embodiment, the information about the paired relay UE(s) may include the number of the paired relay UE(s) and optionally the relay UE ID which may be allocated by the remote UE. A gNB may enable/ disable the remote UE to report (certain part of) the information of the paired relay UE(s). The remote UE may only report (certain part of) the information of the paired relay UE(s) when one or more of the paired relay UE(s) inform a change of serving cell. In accordance with another exemplary embodiment, both the remote UE and the relay UE may report information of the paired peer UE(s) to the gNB. The gNB can determine whether/how to set up the (multipath) relaying based on the reported information. In accordance with an exemplary embodiment, a relay UE may inform the paired remote UE of whether the relay UE can perform (multipath) relaying for the remote UE, and optionally the remote UE may further inform this to the gNB. In accordance with an exemplary embodiment, a remote UE may inform the paired relay UE(s) of a set of candidate cell(s) that the paired relay UE(s) may need to (re)select when in radio resource control (RRC) idle/inactive. The gNB may page the relay UE(s) in RRC idle/inactive to report Uu quality measurement using e.g., SDT.

Many advantages may be achieved by applying the proposed solutions. For example, information about the paired relay/remote UE may be only reported to a gNB when needed, which can avoid unnecessary signaling over the Uu interface. In addition, a relay UE can be identified properly over the Uu interface and the gNB may have full control on relay UE (re)selection, which can provide better performance for (multipath) relaying with ideal inter UE connection.

It can be appreciated that some exemplary embodiments are described with assumption that the UE to UE inter-connection is ideal, however, most of the embodiments are in general applicable to any kind of direct communications between UEs involving D2D communications such as LTE SL, NR SL and non-3GPP D2D communications, as long as the UE to UE inter-connection is ideal.

In various exemplary embodiments, the UE-to-NW relay UE is denoted as relay UE. Further, the term “direct path” is used in order to describe a direct connection between a UE and the network that is operated over the Uu interface. Also, the term “indirect path” is used in order to describe a connection between a UE and the network via a middle node which is called “relay UE” in this document. The UE is also called “remote UE” in these two terms without any loss of meaning. It can be realized that the remote UE can be configured with both direct path and indirect path, unless otherwise declared.

It can be appreciated that exemplary embodiments are described in the scenario where the relay UE and the remote UE operates with the same radio access technology (RAT) over the Uu interface, e.g., NR, LTE, and so on. However, all the embodiments may apply without loss of meaning to any combination of RATs over the Uu interface between the relay UE and the remote UE.

In a first embodiment, a remote UE may send one or more of the following information about one or multiple paired relay UE(s) (denoted as the paired relay UE information hereafter) to the NW (e.g., its serving gNB, etc.):

• The number of the paired relay UE(s).

• ID(s) of the paired relay UE(s). o Each paired relay UE may have a corresponding ID which may be any one of the below forms:

■ Any Uu ID including cell-radio network temporary identifier (C- RNTI), inactive-radio network temporary identifier (I-RNTI), resume ID, paging-radio network temporary identifier (P-RNTI) etc. A Uu ID may be only applicable to the relay UE in specific RRC state. C-RNTI may be only applicable to the relay UE which is in RRC INACTIVE or RRC CONNECTED, while I-RNTI or resume ID may only be applicable to the relay UE which is in RRC INACTIVE.

■ Temporary or local ID. A temporary or local ID may be applied if the relay UE concerns that its privacy may be affected due to disclosing its Uu ID to the remote UE. o The temporary or local ID may be allocated by the remote UE for each paired relay UE. The format/size of the ID may be configured by the gNB or up to the remote UE implementation. The ID may only be allocated when the number of paired relay UE(s) is more than one. In case the ID is not allocated, the remote UE may indicate an ID with empty field or a specific (pre)configured value to the NW. The remote UE may also inform the allocated ID to the corresponding paired relay UE. o For each paired relay UE, in case a Uu ID is applied for the paired relay UE, the relay UE may inform the Uu ID to the remote UE via the ideal inter UE connection. The relay UE may send its Uu ID proactively or based on a request from the remote UE.

• The serving cell(s) of the paired relay UE(s). o Each paired relay UE may have at least one serving cell. o The remote UE may obtain this information from the paired relay UE over the UE to UE interface. The relay UE may only inform the cell information to the paired remote UE when it is in RRC idle/inactive and (re)select a serving cell.

The remote UE may send the paired relay UE information by RRC signaling to the NW, e.g., to its serving gNB.

In a second embodiment, a gNB may enable/disable a remote UE to report (certain part of) the paired relay UE information.

• For instance, the remote UE may first only report the number of paired relay UE(s) when it (re)establishes the RRC connection to the gNB or is requested by the gNB to do so.

• The gNB may disable the remote UE to report (the other part of) the paired relay UE information when all (or most of) the relay UE(s) paired to the remote UE is in RRC connected (and being served by the gNB), otherwise the report is enabled.

• Besides, in case the remote UE is already configured with an indirect path, the gNB may enable/disable the remote UE to report (the other part of) the paired relay UE information when e.g., the Uu quality of the paired relay UE of the configured indirect path is worse/better than a certain level.

• When the report is enabled, the remote UE may only report (the other part of) the paired relay UE information when one or more of the paired relay UE(s) have indicated a change of serving cell. The paired relay UE(s) may only inform serving cell change when they are in RRC idle/inactive. The remote UE may only report (the other part of) the paired relay UE information containing (at least) information of the paired relay UE(s) that have indicated a serving cell change since the last time the information is reported.

In a third embodiment, a relay UE may send one or more of the following information to the NW (e.g., its serving gNB):

• The ID of the relay UE as described in the first embodiment, such information may only be needed when a temporary or local ID is applied for the relay UE. When this ID has not been allocated by the remote UE (e.g., in case the remote UE is only paired with one relay UE), the relay UE may indicate an ID with empty field or a specific (pre)configured value to the NW.

An ID of the paired remote UE. The relay UE may obtain this ID from the paired remote UE over the UE to UE interface. The ID may be one of the followings: o An ID of the remote UE used over Uu interface, e.g., C-RNTI, I-RNTI, resume ID, P-RNTI, etc. As an option, the I-RNTI may be used since it is unique in more than the cell serving the remote UE. A Uu ID may be only applicable to the remote UE in specific RRC state. For example, C-RNTI may be only applicable to the remote UE which is in RRC CONNECTED, while I-RNTI or resume ID is only applicable to the remote UE which is in RRC INACTIVE. o A temporary or local ID which maps to an Uu ID of the remote UE. The mapping relationship can be stored by the remote UE’s gNB. The temporary or local ID may be allocated by either the remote UE itself or the remote UE’s gNB and shared between the remote UE and its serving gNB. The temporary or local ID may be updated when e.g., after a certain time period and/or the remote UE switches the serving cell.

In accordance with an exemplary embodiment, the relay UE may only send such information when in RRC connected and when the paired remote UE has informed its ID. The paired remote UE may only inform its ID to the relay UE when the ID is updated.

The relay UE may send the paired relay UE information by RRC signaling to the NW, e.g., to its serving gNB.

In another option, a relay UE in RRC INACTIVE may report the above information using small data transmissions (SDT). In this case, the relay UE may not be required to go to RRC CONNECTED. As an additional option, the reported information may further contain the Uu quality measurement (e.g., RSRP) of the cell where the relay UE is camping on.

In a fourth embodiment, based on the information sent by remote UE(s) and/or relay UE(s), a gNB can identify one or more of the following information:

• The relay UE(s) that are paired to a remote UE.

• Whether the relay UE(s) and the paired remote UE are all served by cell(s) belonging to the same gNB.

• Whether the relay UE(s) are in RRC connected (which may be checked by the remote UE’s gNB), the remote UE’s gNB may only check the RRC status of the paired relay UE(s) which are served by itself.

Then for a remote UE, the gNB can determine whether any of the paired relay UE(s) may be used to set up (multipath) relaying for the remote UE, and if there exist multiple such relay UEs, which relay UE to select, e.g., the gNB may prioritize the relay UE in RRC connected and/or with good Uu quality in terms of metrics including RSRP, reference signal received quality (RSRQ), received signal strength indicator (RSSI), etc.

In a fifth embodiment, a gNB may configure a Uu threshold for a relay UE above which the relay UE may be allowed to perform (multipath) relaying for the paired remote UE. Such threshold may only be configured for the relay UE in RRC idle/inactive. The relay UE (in RRC idle/inactive) may inform the paired remote UE over the UE to UE interface whether it can perform (multipath) relaying for the remote UE and the remote UE may further inform this to the gNB. In an embodiment, the remote UE may only send (the other part of) the paired relay UE information about the paired relay UE(s) that can perform (multipath) relaying for it to the gNB.

In a sixth embodiment, a remote UE may inform a set of candidate cell(s) that the pair relay UE(s) may need to (re)select when in RRC idle/inactive. Such cell(s) may be any of the following:

• The cell that currently serves the remote UE.

• A set of cell(s) indicated by the gNB of the remote UE, the gNB may indicate a set of cell(s) owned by itself to the remote UE. The set of cell(s) may include a neighbor cell of the cell that currently serves the remote UE. In an embodiment, the gNB may indicate a set of cell(s) owned by itself and having good Uu quality to the remote UE in terms of metrics including RSRP, RSRQ, RSSI, etc.

In accordance with an exemplary embodiment, the paired relay UE(s) in RRC idle/inactive may then prioritize (re)selection of cell(s) belonging to the informed set of candidate cell(s), and may inform the remote UE whether it has (re)selected a cell belonging to the informed set of candidate cell(s). The remote UE may further inform this to the gNB. In an embodiment, the remote UE may only send (the other part of) the paired relay UE information about the paired relay UE(s) that have (re)selected a cell belonging to the informed set of candidate cell(s).

In a seventh embodiment, the gNB serving one or more remote UE(s) may page the relay UE(s) paired to the remote UE(s) to report its Uu measurements such as RSRP. The gNB may only send such paging when (some of) the paired relay UE(s) are in RRC idle/inactive. The gNB may only page the paired relay UE(s) in the cells where the paired relay UE(s) are camping (the gNB can know the cell information from the remote UE as described in the first embodiment).

In accordance with an exemplary embodiment, the paging message may include one or more of the following information:

• The ID of the relay UE(s): in this case, only the relevant relay UE(s) may response to the paging message.

• The ID of the remote UE(s): in this case, only the relay UE(s) paired to the remote UE(s) may response to the paging message.

• An indication to indicate that it is for Uu quality report only, i.e., it may not require the relevant relay UEs to perform other actions such as entering RRC connected for traffic transmission.

• A list of cells for which the Uu measurement may need to be reported. It may be (pre)configured that the Uu measurements of the cell where the relay UE is camping may need to be reported even the cell is not included in the list or the list is empty.

In one option of this embodiment, the SDT procedure may be used to convey the Uu measurements of the cell where the relay UE is camping and possibly of the cells indicated in the paging message. In this case, the relay UE may remain in RRC inactive. In another option, the relay UE may transit to RRC connected according to legacy procedures to report the Uu measurement.

Fig.l is a diagram illustrating an exemplary signaling flow for information exchange according to an embodiment of the present disclosure. As shown in Fig.l, information exchange may occur between UEs (e.g., between a remote UE and a relay UE1, and between the remote UE and a relay UE 2) and between a UE and a gNB (e.g., between the remote UE and the gNB, between the relay UE1 and the gNB, and between the relay UE2 and the gNB). According to the signaling flow shown in Fig.l, the remote UE may send (certain part of) pairing relay UE information (e.g., the number of the paired relay UE(s), etc.) to the gNB, and inform its ID and the paired relay UE’s ID to the corresponding relay UE. The remote UE may send the (certain part of) the pairing relay UE information by RRC signaling to the gNB. The ID for the paired relay UE may be allocated by the remote UE. Alternatively, the ID for the paired relay UE could be allocated by the relay UE (UE1/UE2) itself or by the gNB. The relay UE (UE1/UE2) may inform its serving cell ID to the remote UE. In some cases, the relay UE (UE1/UE2) could also inform its ID to the remote UE. The gNB may enable informing of (the other part of) the pairing relay UE information by the remote UE. Then the remote UE may send (the other part of) the pairing relay UE information to the gNB which may optionally receive information of the paired remote UE from the relay UE1/UE2. Based on the information reported by the remote UE and/or the relay UE1/UE2, the gNB can determine which relay UE to select for the remote UE, and (re)configure the indirect path for the remote UE via the selected relay UE.

It can be appreciated that Fig.l is only an example, some signaling messages are optional, e.g., the message indicating the number of the paired relay UEs, or the message indicating the serving cell ID, or the message indicating (the other part of) the information of the paired relay UE, etc. The signaling order of messages may vary, e.g., the relay UE may inform its serving cell ID to the paired remote UE before the remote UE informs its own ID and the ID for the relay UE to the relay UE, the relay UE may inform information of the paired remote UE before the remote UE informs (the other part of) the information of the paired relay UE to the gNB, etc.

It is noted that some embodiments of the present disclosure are mainly described in relation to 4G/LTE or 5G/NR specifications being used as non-limiting examples for certain exemplary network configurations and system deployments. As such, the description of exemplary embodiments given herein specifically refers to terminology which is directly related thereto. Such terminology is only used in the context of the presented non-limiting examples and embodiments, and does naturally not limit the present disclosure in any way. Rather, any other system configuration or radio technologies may equally be utilized as long as exemplary embodiments described herein are applicable.

Fig.2 is a flowchart illustrating a method 200 according to some embodiments of the present disclosure. The method 200 illustrated in Fig.2 may be performed by a first terminal device (e.g., a remote UE, etc.) or an apparatus communicatively coupled to the first terminal device. In accordance with an exemplary embodiment, the first terminal device may be configured to support D2D communication with other devices. In an exemplary embodiment, the first terminal device may be configured to communicate with a network node (e.g., a base station such as gNB, etc.) directly or via a relay.

According to the exemplary method 200 illustrated in Fig.2, the first terminal device may determine pairing information of the first terminal device, as shown in block 202. The pairing information of the first terminal device may be related to one or more devices which are relaying capable devices paired to the first terminal device. The one or more devices may include at least a second terminal device. In accordance with an exemplary embodiment, the first terminal device may transmit at least part of the pairing information of the first terminal device towards a network node, as shown in block 204. The first terminal device may transmit the at least part of the pairing information by RRC signaling.

In accordance with an exemplary embodiment, the one or more identifiers of the one or more devices may include one or more of: one or more Uu identifiers of the one or more devices; one or more temporary identifiers of the one or more devices; and one or more local identifiers of the one or more devices. In an embodiment, the one or more temporary identifiers and/or the one or more local identifiers of the one or more devices may be allocated by the first terminal device.

In accordance with an exemplary embodiment, the first terminal device may inform an identifier of the first terminal device and/or an identifier of the second terminal device to the second terminal device. In accordance with another exemplary embodiment, the first terminal device may receive information indicating an identifier of the second terminal device and/or a serving cell of the second terminal device from the second terminal device.

In accordance with an exemplary embodiment, the first terminal device may receive, from the network node, configuration information for enabling or disabling at least partial reporting of the pairing information of the first terminal device towards the network node. In an embodiment, the configuration information may be based at least in part on one or more the following factors:

• a demand of the network node;

• a state of a connection between the first terminal device and the network node;

• a state of connections between the one or more devices and the network node;

• link quality over Uu interface of an indirect path configured to the first terminal device; and

• link quality over Uu interface between the one or more devices and the network node.

In accordance with an exemplary embodiment, the transmission of the at least part of the pairing information of the first terminal device towards the network node may be enabled or disabled based at least in part on one or more the following factors:

• configuration information from the network node;

• a change of information about the one or more devices;

• capabilities of the one or more devices to perform relaying to the network node for the first terminal device; and

• a result of cell selection or reselection of the one or more devices.

In accordance with an exemplary embodiment, the first terminal device may receive, from the second terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device. In accordance with another exemplary embodiment, the first terminal device may transmit, towards the network node, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, the first terminal device may transmit, to the second terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device. In an embodiment, the set of the candidate cells may include one or more of: a serving cell of the first terminal device; and one or more cells indicated by the network node.

In accordance with an exemplary embodiment, the first terminal device may receive, from the second terminal device, information indicating whether the second terminal device selects a cell from the set of the candidate cells. In accordance with another exemplary embodiment, the first terminal device may transmit, towards the network node, information indicating whether the second terminal device selects a cell from the set of the candidate cells.

In accordance with an exemplary embodiment, the first terminal device may establish an indirect path between the first terminal and the network node via a relay device. In an embodiment, the relay device may be selected from the one or more devices by the network node, according to the at least part of the pairing information of the first terminal device and/or information reported to the network node by at least one of the one or more devices paired to the first terminal device.

Fig.3 is a flowchart illustrating a method 300 according to some embodiments of the present disclosure. The method 300 illustrated in Fig.3 may be performed by a second terminal device (e.g., a relay UE, etc.) or an apparatus communicatively coupled to the second terminal device. In accordance with an exemplary embodiment, the second terminal device may be configured to support D2D communication with other devices. In an exemplary embodiment, the second terminal device may be configured to communicate with a network node (e.g., a base station such as gNB, etc.) directly or via a relay. In another exemplary embodiment, the second terminal device may be configured to act as a relay UE for one or more other UEs.

According to the exemplary method 300 illustrated in Fig.3, the second terminal device which is a relaying capable device paired to a first terminal device (e.g., the first terminal device as described with respect to Fig.2), may determine pairing information of the second terminal device, as shown in block 302. The pairing information of the second terminal device may indicate an identifier of the second terminal device. In accordance with an exemplary embodiment, the second terminal device may transmit information indicating the identifier of the second terminal device to the first terminal device, as shown in block 304.

In accordance with an exemplary embodiment, the second terminal device may obtain the identifier of the second terminal device from a network node, e.g., a network node associated with a serving cell of the second terminal device.

In accordance with an exemplary embodiment, the identifier of the second terminal device may be a Uu identifier, a temporary identifier or a local identifier of the second terminal device. In an embodiment, the temporary identifier and/or the local identifier of the second terminal device may be allocated by the first terminal device. The temporary identifier may of the second terminal device may be a C-RNTI, an I-RNTI, or a P-RNTI.

In accordance with an exemplary embodiment, the second terminal device may transmit information indicating a serving cell of the second terminal device to the first terminal device.

In accordance with an exemplary embodiment, the second terminal device may determine whether the second terminal device is capable of performing relaying to the network node for the first terminal device. In an embodiment, when Uu link quality of the second terminal device is above a threshold configured by the network node, the second terminal device may determine that the second terminal device is capable of performing relaying to the network node for the first terminal device. In accordance with another exemplary embodiment, the second terminal device may transmit, to the first terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, the second terminal device may receive, from the first terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device. In an embodiment, the set of the candidate cells may include one or more of: a serving cell of the first terminal device; and one or more cells indicated by a network node, e.g., a network node associated with a serving cell of the second terminal device.. In accordance with an exemplary embodiment, the second terminal device may determine whether to select a cell from the set of the candidate cells. In accordance with another exemplary embodiment, the second terminal device may transmit, to the first terminal device, information indicating whether the second terminal device selects the cell from the set of the candidate cells.

In accordance with an exemplary embodiment, the second terminal device may receive a paging message from the network node. The paging message may instruct the second terminal device to report one or more Uu quality measurements of the second terminal device. In an embodiment, the paging message may include one or more of:

• an identifier of the first terminal device;

• an identifier of the second terminal device;

• information indicating that the paging message is for Uu quality reporting only; and

• information about a list of cells for which Uu quality measurements need to be reported.

In accordance with an exemplary embodiment, the second terminal device may transmit one or more of the following information towards a network node in an SDT procedure: the at least part of the pairing information of the second terminal device; and one or more Uu quality measurements of the second terminal device. The network node may be a network node associated with a serving cell of the second terminal device.

Fig.4 is a flowchart illustrating a method 400 according to some embodiments of the present disclosure. The method 400 illustrated in Fig.4 may be performed by a second terminal device (e.g., a relay UE, etc.) or an apparatus communicatively coupled to the second terminal device. In accordance with an exemplary embodiment, the second terminal device may be configured to support D2D communication with other devices. In an exemplary embodiment, the second terminal device may be configured to communicate with a network node (e.g., a base station such as gNB, etc.) directly or via a relay. In another exemplary embodiment, the second terminal device may be configured to act as a relay UE for one or more other UEs.

According to the exemplary method 400 illustrated in Fig.4, the second terminal device which is a relaying capable device paired to a first terminal device (e.g., the first terminal device as described with respect to Fig.2), may determine pairing information of the second terminal device, as shown in block 402. The pairing information of the second terminal device may indicate an identifier of the first terminal device and/or an identifier of the second terminal device. In accordance with an exemplary embodiment, the second terminal device may transmit at least part of the pairing information of the second terminal device towards a network node, as shown in block 404. The second terminal device may transmit the at least part of the pairing information by RRC signaling.

In accordance with an exemplary embodiment, the second terminal device may receive the identifier of the first terminal device and/or the identifier of the second terminal device from the first terminal device.

In accordance with an exemplary embodiment, the identifier of the first terminal device may be a Uu identifier, a temporary identifier or a local identifier of the first terminal device. The temporary identifier of the first terminal device may be a C-RNTI, an I- RNTI, or a P-RNTI. In an embodiment, the temporary identifier and/or the local identifier of the first terminal device may be allocated by the first terminal device or the network node.

In accordance with an exemplary embodiment, the identifier of the second terminal device may be a Uu identifier, a temporary identifier or a local identifier of the second terminal device. The temporary identifier of the second terminal device may be a C- RNTI, an I-RNTI, or a P-RNTI. In an embodiment, the temporary identifier and/or the local identifier of the second terminal device may be allocated by the first terminal device.

In accordance with an exemplary embodiment, the second terminal device may transmit information indicating the identifier of the second terminal device and/or a serving cell of the second terminal device to the first terminal device.

In accordance with an exemplary embodiment, the second terminal device may receive, from the first terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device. In an embodiment, the set of the candidate cells may include one or more of: a serving cell of the first terminal device; and one or more cells indicated by the network node.

In accordance with an exemplary embodiment, the second terminal device may determine whether to select a cell from the set of the candidate cells. In accordance with another exemplary embodiment, the second terminal device may transmit, to the first terminal device, information indicating whether the second terminal device selects the cell from the set of the candidate cells.

• an identifier of the first terminal device;

• an identifier of the second terminal device;

In accordance with an exemplary embodiment, the second terminal device may transmit one or more of the following information towards the network node in an SDT procedure: the at least part of the pairing information of the second terminal device; and one or more Uu quality measurements of the second terminal device.

It can be appreciated that the first terminal device as described with respect to Fig.2 may also be configured to perform the method 300 as described with respect to Fig.3 and/or the method as described with respect to Fig.4, according to different application scenarios and service requirements. Similarly, it can be appreciated that the second terminal device as described with respect to Fig.3 or with respect to Fig.4 may also be configured to perform the method 200 as described with respect to Fig.2, according to different application scenarios and service requirements.

Fig.5 is a flowchart illustrating a method 400 according to some embodiments of the present disclosure. The method 400 illustrated in Fig.5 may be performed by a network node (e.g., a gNB, an AP, etc.) or an apparatus communicatively coupled to the network node. In accordance with an exemplary embodiment, the network node may be configured to support cellular coverage extension with D2D communication. In an exemplary embodiment, the network node may be configured to communicate with a terminal device such as a UE, e.g., directly or via a relay.

According to the exemplary method 400 illustrated in Fig.5, the network node may transmit, towards a first terminal device (e.g., the first terminal device as described with respect to Fig.2), configuration information for enabling or disabling at least partial reporting of pairing information of the first terminal device towards the network node, as shown in block 502. The pairing information of the first terminal device may be related to one or more devices which are relaying capable devices paired to the first terminal device. The one or more devices may include at least a second terminal device (e.g., the second terminal device as described with respect to Fig.3 or Fig.4). In accordance with an exemplary embodiment, the network node may receive at least part of the pairing information which is reported by the first terminal device according to the configuration information, as shown in block 504.

In accordance with an exemplary embodiment, the network node may receive at least part of pairing information of the second terminal device from the second terminal device. The pairing information of the second terminal device may indicate an identifier of the first terminal device and/or an identifier of the second terminal device.

In accordance with an exemplary embodiment, the network node may receive, from the first terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device. In an embodiment, when Uu link quality of the second terminal device is above a threshold configured by the network node, the second terminal device may be capable of performing relaying to the network node for the first terminal device.

In accordance with an exemplary embodiment, the network node may receive, from the first terminal device, information indicating whether the second terminal device selects a cell from a set of the candidate cells available for cell selection or reselection by the second terminal device. In an exemplary embodiment, the set of the candidate cells may include one or more of: a serving cell of the first terminal device; and one or more cells indicated by the network node.

In accordance with an exemplary embodiment, the network node may transmit a paging message towards one or more relay devices paired to one or more remote devices served by the network node. The paging message may instruct the one or more relay devices to report corresponding Uu quality measurements. In an embodiment, the paging message may include one or more of:

• one or more identifiers of the one or more relay devices;

• one or more identifiers of the one or more remote devices;

In accordance with an exemplary embodiment, the network node may determine which of the one or more devices paired to the first terminal device is to be selected as a relay device for the first terminal device, according to the at least part of the pairing information of the first terminal device and/or information reported to the network node by at least one of the one or more devices paired to the first terminal device.

In accordance with an exemplary embodiment, the network node may establish an indirect path between the first terminal and the network node via the relay device selected for the first terminal device from the one or more devices by the network node. The various blocks shown in Figs.2-5 may be viewed as method steps, and/or as operations that result from operation of computer program code, and/or as a plurality of coupled logic circuit elements constructed to carry out the associated function(s). The schematic flow chart diagrams described above are generally set forth as logical flow chart diagrams. As such, the depicted order and labeled steps are indicative of specific embodiments of the presented methods. Other steps and methods may be conceived that are equivalent in function, logic, or effect to one or more steps, or portions thereof, of the illustrated methods. Additionally, the order in which a particular method occurs may or may not strictly adhere to the order of the corresponding steps shown.

Fig.6 is a block diagram illustrating an apparatus 600 according to various embodiments of the present disclosure. As shown in Fig.6, the apparatus 600 may comprise one or more processors such as processor 601 and one or more memories such as memory 602 storing computer program codes 603. The memory 602 may be non-transitory machine/processor/computer readable storage medium. In accordance with some exemplary embodiments, the apparatus 600 may be implemented as an integrated circuit chip or module that can be plugged or installed into a first terminal device as described with respect to Fig.2, a second terminal device as described with respect to Fig.3 or Fig.4, or a network node as described with respect to Fig.5. In such cases, the apparatus 500 may be implemented as a first terminal device as described with respect to Fig.2, a second terminal device as described with respect to Fig.3 or Fig.4, or a network node as described with respect to Fig.5.

In some implementations, the one or more memories 602 and the computer program codes 603 may be configured to, with the one or more processors 601, cause the apparatus 600 at least to perform any operation of the method as described in connection with Fig.2. In other implementations, the one or more memories 602 and the computer program codes 603 may be configured to, with the one or more processors 601, cause the apparatus 600 at least to perform any operation of the method as described in connection with Fig.3 or the method as described in connection with Fig.4. In other implementations, the one or more memories 602 and the computer program codes 603 may be configured to, with the one or more processors 601, cause the apparatus 600 at least to perform any operation of the method as described in connection with Fig.5. Alternatively or additionally, the one or more memories 602 and the computer program codes 603 may be configured to, with the one or more processors 601, cause the apparatus 600 at least to perform more or less operations to implement the proposed methods according to the exemplary embodiments of the present disclosure.

Fig.7A is a block diagram illustrating a first terminal device 710 according to some embodiments of the present disclosure. As shown in Fig.7 A, the first terminal device 710 may comprise a determining unit 711 and a transmitting unit 712. The determining unit 711 may be operable to carry out the operation in block 202, and the transmitting unit 712 may be operable to carry out the operation in block 204. Optionally, the determining unit 711 and/or the transmitting unit 712 may be operable to carry out more or less operations to implement the proposed methods according to the exemplary embodiments of the present disclosure. It can be appreciated that the first terminal device 710 may also comprise one or more other units alternative or additional to the determining unit 711 and/or the transmitting unit 712, so that the first terminal device 710 may be configured to implement the proposed methods according to the exemplary embodiments of the present disclosure.

Fig.7B is a block diagram illustrating a second terminal device 720 according to some embodiments of the present disclosure. As shown in Fig.7B, the second terminal device 720 may comprise a determining unit 721 and a transmitting unit 722. The determining unit 721 may be operable to carry out the operation in block 302 or the operation in block 402, and the transmitting unit 722 may be operable to carry out the operation in block 304 or the operation in block 404. Optionally, the determining unit 721 and/or the transmitting unit 722 may be operable to carry out more or less operations to implement the proposed methods according to the exemplary embodiments of the present disclosure. It can be appreciated that the second terminal device 720 may also comprise one or more other units alternative or additional to the determining unit 721 and/or the transmitting unit 722, so that the second terminal device 720 may be configured to implement the proposed methods according to the exemplary embodiments of the present disclosure.

Fig.7C is a block diagram illustrating a network node 730 according to some embodiments of the present disclosure. As shown in Fig.7C, the network node 730 may comprise a transmitting unit 731 and a receiving unit 732. The transmitting unit 731 may be operable to carry out the operation in block 502, and the receiving unit 732 may be operable to carry out the operation in block 504. Optionally, the transmitting unit 731 and/or the receiving unit 732 may be operable to carry out more or less operations to implement the proposed methods according to the exemplary embodiments of the present disclosure. It can be appreciated that the network node 730 may also comprise one or more other units alternative or additional to the transmitting unit 731 and/or the receiving unit 732, so that the network node 730 may be configured to implement the proposed methods according to the exemplary embodiments of the present disclosure.

Fig.8 shows an example of a communication system 800 in accordance with some embodiments.

In the example, the communication system 800 includes a telecommunication network 802 that includes an access network 804, such as a radio access network (RAN), and a core network 806, which includes one or more core network nodes 808. The access network 804 includes one or more access network nodes, such as network nodes 810A and 81 OB (one or more of which may be generally referred to as network nodes 810), or any other similar 3rd Generation Partnership Project (3 GPP) access node or non- 3GPP access point. The network nodes 810 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 812A, 812B, 812C, and 812D (one or more of which may be generally referred to as UEs 812) to the core network 806 over one or more wireless connections.

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 800 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 800 may include and/or interface with any type of communication, telecommunication, data, cellular, radio network, and/or other similar type of system.

The UEs 812 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and/or operable to communicate wirelessly with the network nodes 810 and other communication devices. Similarly, the network nodes 810 are arranged, capable, configured, and/or operable to communicate directly or indirectly with the UEs 812 and/or with other network nodes or equipment in the telecommunication network 802 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 802.

In the depicted example, the core network 806 connects the network nodes 810 to one or more hosts, such as host 816. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 806 includes one more core network nodes (e.g., core network node 808) that are structured with hardware and software components. Features of these components may be 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 808. 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).

The host 816 may be under the ownership or control of a service provider other than an operator or provider of the access network 804 and/or the telecommunication network 802, and may be operated by the service provider or on behalf of the service provider. The host 816 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.

As a whole, the communication system 800 of Fig.8 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be 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 802 is a cellular network that implements 3 GPP standardized features. Accordingly, the telecommunications network 802 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 802. For example, the telecommunications network 802 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.

In some examples, the UEs 812 are configured to transmit and/or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 804 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 804. Additionally, a UE may be configured for operating in single- or multi-RAT or multistandard 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).

In the example, the hub 814 communicates with the access network 804 to facilitate indirect communication between one or more UEs (e.g., UE 812C and/or 812D) and network nodes (e.g., network node 810B). In some examples, the hub 814 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 814 may be a broadband router enabling access to the core network 806 for the UEs. As another example, the hub 814 may be 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 810, or by executable code, script, process, or other instructions in the hub 814. As another example, the hub 814 may be 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 814 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 814 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 814 then provides to the UE either directly, after performing local processing, and/or after adding additional local content. In still another example, the hub 814 acts as a proxy server or orchestrator for the UEs, in particular in if one or more of the UEs are low energy loT devices.

The hub 814 may have a constant/persistent or intermittent connection to the network node 81 OB. The hub 814 may also allow for a different communication scheme and/or schedule between the hub 814 and UEs (e.g., UE 812C and/or 812D), and between the hub 814 and the core network 806. In other examples, the hub 814 is connected to the core network 806 and/or one or more UEs via a wired connection. Moreover, the hub 814 may be configured to connect to an M2M service provider over the access network 804 and/or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 810 while still connected via the hub 814 via a wired or wireless connection. In some embodiments, the hub 814 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 81 OB. In other embodiments, the hub 814 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 81 OB, but which is additionally capable of operating as a communication start and/or end point for certain data channels.

Fig.9 is a block diagram of a host 900, which may be an embodiment of the host 816 of Fig.8, in accordance with various aspects described herein. As used herein, the host 900 may be or comprise various combinations hardware and/or software, including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm. The host 900 may provide one or more services to one or more UEs.

The host 900 includes processing circuitry 902 that is operatively coupled via a bus 904 to an input/output interface 906, a network interface 908, a power source 910, and a memory 912. Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such as Figs.6A-6C, such that the descriptions thereof are generally applicable to the corresponding components of host 900.

The memory 912 may include one or more computer programs including one or more host application programs 914 and data 916, which may include user data, e.g., data generated by a UE for the host 900 or data generated by the host 900 for a UE. Embodiments of the host 900 may utilize only a subset or all of the components shown. The host application programs 914 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), MPEG, VP9) and audio codecs (e.g., FLAC, Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers, wearable display systems, heads-up display systems). The host application programs 914 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network. Accordingly, the host 900 may select and/or indicate a different host for over-the-top services for a UE. The host application programs 914 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (MPEG-DASH), etc.

Fig.10 shows a communication diagram of a host 1002 communicating via a network node 1004 with a UE 1006 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as a UE 812A of Fig.8), network node (such as network node 810A of Fig.8), and host (such as host 816 of Fig.8 and/or host 900 of Fig.9) discussed in the preceding paragraphs will now be described with reference to Fig.10.

Like host 900, embodiments of host 1002 include hardware, such as a communication interface, processing circuitry, and memory. The host 1002 also includes software, which is stored in or accessible by the host 1002 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 1006 connecting via an over-the-top (OTT) connection 1050 extending between the UE 1006 and host 1002. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 1050.

The network node 1004 includes hardware enabling it to communicate with the host 1002 and UE 1006. The connection 1060 may be direct or pass through a core network (like core network 806 of Fig.8) and/or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network may be a backbone network or the Internet.

The UE 1006 includes hardware and software, which is stored in or accessible by UE 1006 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 1006 with the support of the host 1002. In the host 1002, an executing host application may communicate with the executing client application via the OTT connection 1050 terminating at the UE 1006 and host 1002. 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 1050 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 1050.

The OTT connection 1050 may extend via a connection 1060 between the host 1002 and the network node 1004 and via a wireless connection 1070 between the network node 1004 and the UE 1006 to provide the connection between the host 1002 and the UE 1006. The connection 1060 and wireless connection 1070, over which the OTT connection 1050 may be provided, have been drawn abstractly to illustrate the communication between the host 1002 and the UE 1006 via the network node 1004, without explicit reference to any intermediary devices and the precise routing of messages via these devices. For example, the UE1006 could correspond to the remote UE of any of the embodiments illustrated above and be connected to the network node 1004 via a relay UE selected in accordance with the principles of the embodiments illustrated above.

As an example of transmitting data via the OTT connection 1050, in step 1008, the host 1002 provides user data, which may be performed by executing a host application. In some embodiments, the user data is associated with a particular human user interacting with the UE 1006. In other embodiments, the user data is associated with a UE 1006 that shares data with the host 1002 without explicit human interaction. In step 1010, the host 1002 initiates a transmission carrying the user data towards the UE 1006. The host 1002 may initiate the transmission responsive to a request transmitted by the UE 1006. The request may be caused by human interaction with the UE 1006 or by operation of the client application executing on the UE 1006. The transmission may pass via the network node 1004, in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 1012, the network node 1004 transmits to the UE 1006 the user data that was carried in the transmission that the host 1002 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 1014, the UE 1006 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 1006 associated with the host application executed by the host 1002.

In some examples, the UE 1006 executes a client application which provides user data to the host 1002. The user data may be provided in reaction or response to the data received from the host 1002. Accordingly, in step 1016, the UE 1006 may provide user data, which may be 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 1006. Regardless of the specific manner in which the user data was provided, the UE 1006 initiates, in step 1018, transmission of the user data towards the host 1002 via the network node 1004. In step 1020, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 1004 receives user data from the UE 1006 and initiates transmission of the received user data towards the host 1002. In step 1022, the host 1002 receives the user data carried in the transmission initiated by the UE 1006.

One or more of the various embodiments improve the performance of OTT services provided to the UE 1006 using the OTT connection 1050, in which the wireless connection 1070 forms the last segment. More precisely, the teachings of these embodiments may improve the traffic performance such as data rate, latency and power consumption, and thereby provide benefits such as lower complexity, reduced user waiting time, relaxed restriction on file size, improved content resolution, better responsiveness, extended battery lifetime, etc.

In an example scenario, factory status information may be collected and analyzed by the host 1002. As another example, the host 1002 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 1002 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, the host 1002 may store surveillance video uploaded by a UE. As another example, the host 1002 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 1002 may be 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.

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 1050 between the host 1002 and UE 1006, 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 1002 and/or UE 1006. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 1050 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 1050 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not directly alter the operation of the network node 1004. Such procedures and functionalities may be 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 1002. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 1050 while monitoring propagation times, errors, etc.

According to some exemplary embodiments, there is provided a host configured to operate in a communication system to provide an over-the-top (OTT) service. The host may comprise: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a network node in a cellular network for transmission to a user equipment (UE). The network node may have a communication interface and processing circuitry, and the processing circuitry of the network node may be configured to perform operations of the exemplary method 500 as described with respect to Fig.5 to transmit the user data from the host to the UE. In an embodiment, the processing circuitry of the host may be configured to execute a host application that provides the user data, and the UE may comprise processing circuitry configured to execute a client application associated with the host application to receive the transmission of user data from the host.

According to some exemplary embodiments, there is provided a method implemented in a host configured to operate in a communication system that further includes a network node and a user equipment (UE). The method may comprise: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node. The network node may perform operations of the exemplary method 500 as described with respect to Fig.5 to transmit the user data from the host to the UE. In an embodiment, the method may further comprise: at the network node, transmitting the user data provided by the host for the UE. In another embodiment, the user data may be provided at the host by executing a host application that interacts with a client application executing on the UE, the client application being associated with the host application.

According to some exemplary embodiments, there is provided a communication system configured to provide an over-the-top service. The communication system may comprise a host comprising: processing circuitry configured to provide user data for a user equipment (UE), the user data being associated with the over-the-top service; and a network interface configured to initiate transmission of the user data toward a cellular network node for transmission to the UE. The network node may have a communication interface and processing circuitry, and the processing circuitry of the network node may be configured to perform operations of the exemplary method 500 as described with respect to Fig.5 to transmit the user data from the host to the UE. In an embodiment, the communication system may further comprise the network node and/or the user equipment. In another embodiment, the processing circuitry of the host may be configured to execute a host application, thereby providing the user data; and the host application may be configured to interact with a client application executing on the UE, the client application being associated with the host application.

According to some exemplary embodiments, there is provided a host configured to operate in a communication system to provide an over-the-top (OTT) service. The host may comprise: processing circuitry configured to initiate receipt of user data; and a network interface configured to receive the user data from a network node in a cellular network. The network node may have a communication interface and processing circuitry, and the processing circuitry of the network node may be configured to perform operations of the exemplary method 500 as described with respect to Fig.5 to receive the user data from the UE for the host. In an embodiment, the processing circuitry of the host may be configured to execute a host application, thereby providing the user data; and the host application may be configured to interact with a client application executing on the UE, the client application being associated with the host application. In another embodiment, the initiating receipt of the user data may comprise requesting the user data.

According to some exemplary embodiments, there is provided a method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE). The method may comprise: at the host, initiating receipt of user data from the UE, the user data originating from a transmission which the network node has received from the UE. The network node may perform operations of the exemplary method 500 as described with respect to Fig.5 to receive the user data from the UE for the host. In an embodiment, the method may further comprise: at the network node, transmitting the received user data to the host.

According to some exemplary embodiments, there is provided a host configured to operate in a communication system to provide an over-the-top (OTT) service. The host may comprise: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE). The UE may comprise a communication interface and processing circuitry, and the communication interface and processing circuitry of the UE may be configured to perform operations of the exemplary method 200 as described with respect to Fig.2 or the exemplary method 300 as described with respect to Fig.3 or the exemplary method 400 as described with respect to Fig.4 to receive the user data from the host. In an embodiment, the cellular network may further include a network node configured to communicate with the UE to transmit the user data to the UE from the host. In another embodiment, the processing circuitry of the host may be configured to execute a host application, thereby providing the user data; and the host application may be configured to interact with a client application executing on the UE, the client application being associated with the host application.

According to some exemplary embodiments, there is provided a method implemented by a host operating in a communication system that further includes a network node and a user equipment (UE). The method may comprise: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node. The UE may perform operations of the exemplary method 200 as described with respect to Fig.2 or the exemplary method 300 as described with respect to Fig.3 or the exemplary method 400 as described with respect to Fig.4 to receive the user data from the host. In an embodiment, the method may further comprise: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE. In another embodiment, the method may further comprise: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application. The user data may be provided by the client application in response to the input data from the host application.

According to some exemplary embodiments, there is provided a host configured to operate in a communication system to provide an over-the-top (OTT) service. The host may comprise: processing circuitry configured to utilize user data; and a network interface configured to receipt of transmission of the user data to a cellular network for transmission to a user equipment (UE). The UE may comprise a communication interface and processing circuitry, and the communication interface and processing circuitry of the UE may be configured to perform operations of the exemplary method 200 as described with respect to Fig.2 or the exemplary method 300 as described with respect to Fig.3 or the exemplary method 400 as described with respect to Fig.4 to transmit the user data to the host. In an embodiment, the cellular network may further include a network node configured to communicate with the UE to transmit the user data from the UE to the host. In another embodiment, the processing circuitry of the host may be configured to execute a host application, thereby providing the user data, and the host application may be configured to interact with a client application executing on the UE, the client application being associated with the host application.

According to some exemplary embodiments, there is provided a method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE). The method may comprise: at the host, receiving user data transmitted to the host via the network node by the UE. The UE may perform operations of the exemplary method 200 as described with respect to Fig.2 or the exemplary method 300 as described with respect to Fig.3 or the exemplary method 400 as described with respect to Fig.4 to transmit the user data to the host. In an embodiment, the method may further comprise: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE. In another embodiment, the method may further comprise: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application. The user data may be provided by the client application in response to the input data from the host application.

In general, the various exemplary embodiments may be implemented in hardware or special purpose chips, circuits, software, logic or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the disclosure is not limited thereto. While various aspects of the exemplary embodiments of this disclosure may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

As such, it should be appreciated that at least some aspects of the exemplary embodiments of the disclosure may be practiced in various components such as integrated circuit chips and modules. It should thus be appreciated that the exemplary embodiments of this disclosure may be realized in an apparatus that is embodied as an integrated circuit, where the integrated circuit may comprise circuitry (as well as possibly firmware) for embodying at least one or more of a data processor, a digital signal processor, baseband circuitry and radio frequency circuitry that are configurable so as to operate in accordance with the exemplary embodiments of this disclosure.

It should be appreciated that at least some aspects of the exemplary embodiments of the disclosure may be embodied in computer-executable instructions, such as in one or more program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types when executed by a processor in a computer or other device. The computer executable instructions may be stored on a computer readable medium such as a hard disk, optical disk, removable storage media, solid state memory, random access memory (RAM), etc. As will be appreciated by one of skill in the art, the function of the program modules may be combined or distributed as desired in various embodiments. In addition, the function may be embodied in whole or partly in firmware or hardware equivalents such as integrated circuits, field programmable gate arrays (FPGA), and the like.

The present disclosure includes any novel feature or combination of features disclosed herein either explicitly or any generalization thereof. Various modifications and adaptations to the foregoing exemplary embodiments of this disclosure may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings. However, any and all modifications will still fall within the scope of the non-limiting and exemplary embodiments of this disclosure.

In view of the above, example embodiments of the present disclosure include the following:

Example embodiment 1 :

A method (200) performed by a first terminal device, comprising: determining (202) pairing information of the first terminal device, wherein the pairing information is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and transmitting (204) at least part of the pairing information of the first terminal device towards a network node.

Example embodiment 2:

The method according to example embodiment 1 , wherein the pairing information of the first terminal device indicates one or more of: a number of the one or more devices; one or more identifiers of the one or more devices; and one or more serving cells of the one or more devices.

Example embodiment 3 :

The method according to example embodiment 2, wherein the one or more identifiers of the one or more devices include one or more of: one or more Uu identifiers of the one or more devices; one or more temporary identifiers of the one or more devices; and one or more local identifiers of the one or more devices.

Example embodiment 4:

The method according to example embodiment 3, wherein the one or more temporary identifiers and/or the one or more local identifiers of the one or more devices are allocated by the first terminal device.

Example embodiment 5 :

The method according to example embodiment 3 or 4, wherein the one or more temporary identifiers comprise a cell-radio network temporary identifier, C-RNTI, an inactive-radio network temporary identifier, I-RNTI, and/or a paging-radio network temporary identifier, P-RNTI.

Example embodiment 6: The method according to any of example embodiments 1-5, further comprising: informing an identifier of the first terminal device and/or an identifier of the second terminal device to the second terminal device.

Example embodiment 7 :

The method according to any of example embodiments 1-6, further comprising: receiving information indicating an identifier of the second terminal device and/or a serving cell of the second terminal device from the second terminal device.

Example embodiment 8:

The method according to any of example embodiments 1-7, further comprising: receiving, from the network node, configuration information for enabling or disabling at least partial reporting of the pairing information of the first terminal device towards the network node.

Example embodiment 9:

The method according to example embodiment 8, wherein the configuration information is based at least in part on one or more the following factors: a demand of the network node; a state of a connection between the first terminal device and the network node; a state of connections between the one or more devices and the network node; link quality over Uu interface of an indirect path configured to the first terminal device; and link quality over Uu interface between the one or more devices and the network node.

Example embodiment 10:

The method according to any of example embodiments 1-9, wherein the transmission of the at least part of the pairing information of the first terminal device towards the network node is enabled or disabled based at least in part on one or more the following factors: configuration information from the network node; a change of information about the one or more devices; capabilities of the one or more devices to perform relaying to the network node for the first terminal device; and a result of cell selection or reselection of the one or more devices.

Example embodiment 11 :

The method according to any of example embodiments 1-10, further comprising: receiving, from the second terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device. Example embodiment 12:

The method according to any of example embodiments 1-11, further comprising: transmitting, towards the network node, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

Example embodiment 13:

The method according to any of example embodiments 1-12, further comprising: transmitting, to the second terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device.

Example embodiment 14:

The method according to example embodiment 13, wherein the set of the candidate cells include one or more of: a serving cell of the first terminal device; and one or more cells indicated by the network node.

Example embodiment 15 :

The method according to example embodiment 13 or 14, further comprising: receiving, from the second terminal device, information indicating whether the second terminal device selects a cell from the set of the candidate cells. Example embodiment 16:

The method according to any of example embodiments 13-15, further comprising: transmitting, towards the network node, information indicating whether the second terminal device selects a cell from the set of the candidate cells.

Example embodiment 17:

The method according to any of example embodiments 1-16, further comprising: establishing an indirect path between the first terminal and the network node via a relay device, wherein the relay device is selected from the one or more devices by the network node according to the at least part of the pairing information of the first terminal device and/or information reported to the network node by at least one of the one or more devices paired to the first terminal device.

Example embodiment 18:

A first terminal device (500), comprising: one or more processors (501); and one or more memories (502) comprising computer program codes (503), the one or more memories (502) and the computer program codes (503) configured to, with the one or more processors (501), cause the first terminal device (500) at least to: determine pairing information of the first terminal device, wherein the pairing information is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and transmit at least part of the pairing information of the first terminal device towards a network node.

Example embodiment 19:

The first terminal device according to example embodiment 18, wherein the one or more memories and the computer program codes are configured to, with the one or more processors, cause the first terminal device to perform the method according to any one of example embodiments 2-17.

Example embodiment 20:

A first terminal device, the first terminal device being configured to: determine pairing information of the first terminal device, wherein the pairing information is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and transmit at least part of the pairing information of the first terminal device towards a network node.

Example embodiment 21: The first terminal device according to claim 20, wherein the first terminal device is further configured to perform the method according to any one of Example embodiments 2-17.

Example embodiment 22:

A computer-readable medium having computer program codes (503) embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to any one of example embodiments 1-17.

Example embodiment 23 :

A computer program or computer program product comprising program code to be executed by at least one processor of a first terminal device, whereby execution of the program code causes the first terminal device to perform the method according to any one of example embodiments 1-17.

Example embodiment 24:

A method (300) performed by a second terminal device, comprising: determining (302) pairing information of the second terminal device which is a relaying capable device paired to a first terminal device, wherein the pairing information indicates an identifier of the second terminal device; and transmitting (402) information indicating the identifier of the second terminal device to the first terminal device. Example embodiment 25:

The method according to example embodiment 24, wherein the identifier of the second terminal device is a Uu identifier, a temporary identifier or a local identifier of the second terminal device.

Example embodiment 26:

The method according to example embodiment 25, wherein the temporary identifier of the second terminal device comprises a C-RNTI, an I-RNTI, and/or a P-RNTL

Example embodiment 27 :

The method according to any of example embodiments 24-26, further comprising: transmitting information indicating a serving cell of the second terminal device to the first terminal device.

Example embodiment 28:

The method according to any of example embodiments 24-27, further comprising: determining whether the second terminal device is capable of performing relaying to the network node for the first terminal device; and transmitting, to the first terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

Example embodiment 29:

The method according to example embodiment 28, wherein when Uu link quality of the second terminal device is above a threshold configured by the network node, the second terminal device determines that the second terminal device is capable of performing relaying to the network node for the first terminal device.

Example embodiment 30:

The method according to any of example embodiments 24-29, further comprising: receiving, from the first terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device.

Example embodiment 31 :

The method according to example embodiment 30, wherein the set of the candidate cells include one or more of: a serving cell of the first terminal device; and one or more cells indicated by a network node.

Example embodiment 32:

The method according to example embodiment 30 or 31, further comprising: determining whether to select a cell from the set of the candidate cells; transmitting, to the first terminal device, information indicating whether the second terminal device selects the cell from the set of the candidate cells.

Example embodiment 33:

The method according to any of example embodiments 24-32, further comprising: receiving a paging message from a network node, wherein the paging message instructs the second terminal device to report one or more Uu quality measurements of the second terminal device.

Example embodiment 34:

The method according to example embodiment 33, wherein the paging message includes one or more of: an identifier of the first terminal device; an identifier of the second terminal device; information indicating that the paging message is for Uu quality reporting only; and information about a list of cells for which Uu quality measurements need to be reported.

Example embodiment 35:

The method according to any of example embodiments 24-34, wherein the second terminal device transmits one or more of the following information towards the network node in a small data transmission, SDT, procedure: the at least part of the pairing information of the second terminal device; and one or more Uu quality measurements of the second terminal device.

Example embodiment 36:

A second terminal device (500), comprising: one or more processors (501); and one or more memories (502) comprising computer program codes (503), the one or more memories (502) and the computer program codes (503) configured to, with the one or more processors (501), cause the second terminal device (500) at least to: determine pairing information of the second terminal device which is a relaying capable device paired to a first terminal device, wherein the pairing information indicates an identifier of the second terminal device; and transmit information indicating the identifier of the second terminal device to the first terminal device.

Example embodiment 37:

The second terminal device according to example embodiment 36, wherein the one or more memories and the computer program codes are configured to, with the one or more processors, cause the second terminal device to perform the method according to any one of example embodiments 25-35. Example embodiment 38:

A second terminal device, the second terminal device being configured to: determine pairing information of the second terminal device which is a relaying capable device paired to a first terminal device, wherein the pairing information indicates an identifier of the second terminal device; and transmit information indicating the identifier of the second terminal device to the first terminal device.

Example embodiment 39:

The second terminal device according to claim 38, wherein the second terminal device is further configured to perform the method according to any one of example embodiments 25-35.

Example embodiment 40:

A computer-readable medium having computer program codes (503) embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to any one of example embodiments 24-35.

Example embodiment 41:

A computer program or computer program product comprising program code to be executed by at least one processor of a second terminal device, whereby execution of the program code causes the second terminal device to perform the method according to any one of claims 24-35.

Example embodiment 42:

A method (400) performed by a second terminal device, comprising: determining (402) pairing information of the second terminal device which is a relaying capable device paired to a first terminal device, wherein the pairing information indicates an identifier of the first terminal device and/or an identifier of the second terminal device; and transmitting (404) at least part of the pairing information of the second terminal device towards a network node.

Example embodiment 43

The method according to example embodiment 42, further comprising: receiving the identifier of the first terminal device and/or the identifier of the second terminal device from the first terminal device.

Example embodiment 44:

The method according to example embodiment 42 or 43, wherein the identifier of the first terminal device is a Uu identifier, a temporary identifier or a local identifier of the first terminal device. Example embodiment 45

The method according to example embodiment 44, wherein the temporary identifier and/or the local identifier of the first terminal device are allocated by the first terminal device or the network node.

Example embodiment 46:

The method according to example embodiment 44 or 45, wherein the temporary identifier of the first terminal device comprises a cell-radio network temporary identifier, C-RNTI, an inactive-radio network temporary identifier, I-RNTI, and/or a paging-radio network temporary identifier, P-RNTE

Example embodiment 47 :

The method according to any of example embodiments 42-46, wherein the identifier of the second terminal device is a Uu identifier, a temporary identifier or a local identifier of the second terminal device.

Example embodiment 48:

The method according to example embodiment 47, wherein the temporary identifier and/or the local identifier of the second terminal device are allocated by the first terminal device.

Example embodiment 49: The method according to example embodiment 47 or 48, wherein the temporary identifier of the second terminal device comprises a C-RNTI, an I-RNTI, and/or a P- RNTI.

Example embodiment 50:

The method according to any of example embodiments 42-49, further comprising: transmitting information indicating the identifier of the second terminal device and/or a serving cell of the second terminal device to the first terminal device.

Example embodiment 51 :

The method according to any of example embodiments 42-50, further comprising: determining whether the second terminal device is capable of performing relaying to the network node for the first terminal device; and transmitting, to the first terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

Example embodiment 52:

The method according to example embodiment 51 , wherein when Uu link quality of the second terminal device is above a threshold configured by the network node, the second terminal device determines that the second terminal device is capable of performing relaying to the network node for the first terminal device. Example embodiment 53:

The method according to any of example embodiments 42-52, further comprising: receiving, from the first terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device.

Example embodiment 54:

The method according to example embodiment 53, wherein the set of the candidate cells include one or more of: a serving cell of the first terminal device; and one or more cells indicated by the network node.

Example embodiment 55:

The method according to example embodiment 53 or 54, further comprising: determining whether to select a cell from the set of the candidate cells; transmitting, to the first terminal device, information indicating whether the second terminal device selects the cell from the set of the candidate cells.

Example embodiment 56:

The method according to any of example embodiments 42-55, further comprising: receiving a paging message from the network node, wherein the paging message instructs the second terminal device to report one or more Uu quality measurements of the second terminal device.

Example embodiment 57:

The method according to example embodiment 56, wherein the paging message includes one or more of: an identifier of the first terminal device; an identifier of the second terminal device; information indicating that the paging message is for Uu quality reporting only; and information about a list of cells for which Uu quality measurements need to be reported.

Example embodiment 58:

The method according to any of example embodiments 42-57, wherein the second terminal device transmits one or more of the following information towards the network node in a small data transmission, SDT, procedure: the at least part of the pairing information of the second terminal device; and one or more Uu quality measurements of the second terminal device.

Example embodiment 59:

A second terminal device (500), comprising: one or more processors (501); and one or more memories (502) comprising computer program codes (503), the one or more memories (502) and the computer program codes (503) configured to, with the one or more processors (501), cause the second terminal device (500) at least to: determine pairing information of the second terminal device which is a relaying capable device paired to a first terminal device, wherein the pairing information indicates an identifier of the first terminal device and/or an identifier of the second terminal device; and transmit at least part of the pairing information of the second terminal device towards a network node.

Example embodiment 60:

The second terminal device according to example embodiment 59, wherein the one or more memories and the computer program codes are configured to, with the one or more processors, cause the second terminal device to perform the method according to any one of claims 43-58.

Example embodiment 61:

A second terminal device, the second terminal device being configured to: determine pairing information of the second terminal device which is a relaying capable device paired to a first terminal device, wherein the pairing information indicates an identifier of the first terminal device and/or an identifier of the second terminal device; and transmit at least part of the pairing information of the second terminal device towards a network node.

Example embodiment 62:

The second terminal device according to example embodiment 61 , wherein the second terminal device is further configured to perform the method according to any one of example embodiments 43-58.

Example embodiment 63 :

A computer-readable medium having computer program codes (503) embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to any one of example embodiments 42-58.

Example embodiment 64:

A computer program or computer program product comprising program code to be executed by at least one processor of a second terminal device, whereby execution of the program code causes the second terminal device to perform the method according to any one of example embodiments 42-58.

Example embodiment 65: A method (400) performed by a network node, comprising: transmitting (402), towards a first terminal device, configuration information for enabling or disabling at least partial reporting of pairing information of the first terminal device towards the network node, wherein the pairing information of the first terminal device is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and receiving (404) at least part of the pairing information which is reported by the first terminal device according to the configuration information.

Example embodiment 66:

The method according to example embodiment 65, wherein the pairing information of the first terminal device indicates one or more of: a number of the one or more devices; one or more identifiers of the one or more devices; and one or more serving cells of the one or more devices.

Example embodiment 67 :

The method according to example embodiment 66, wherein the one or more identifiers of the one or more devices include one or more of: one or more Uu identifiers of the one or more devices; one or more temporary identifiers of the one or more devices; and one or more local identifiers of the one or more devices.

Example embodiment 68:

The method according to example embodiment 67, wherein the one or more temporary identifiers comprise a cell-radio network temporary identifier, C-RNTI, an inactiveradio network temporary identifier, I-RNTI, and/or a paging-radio network temporary identifier, P-RNTI.

Example embodiment 69:

The method according to any of example embodiments 65-68, wherein the configuration information is determined by the network node based at least in part on one or more the following factors: a demand of the network node; a state of a connection between the first terminal device and the network node; a state of connections between the one or more devices and the network node; link quality over Uu interface of an indirect path configured to the first terminal device; and link quality over Uu interface between the one or more devices and the network node.

Example embodiment 70:

The method according to any of example embodiments 65-69, wherein the at least partial reporting of the pairing information of the first terminal device towards the network node is enabled or disabled also based at least in part on one or more the following factors: a change of information about the one or more devices; capabilities of the one or more devices to perform relaying to the network node for the first terminal device; and a result of cell selection or reselection of the one or more devices.

Example embodiment 71 :

The method according to any of example embodiments 65-70, further comprising: receiving at least part of pairing information of the second terminal device from the second terminal device, wherein the pairing information of the second terminal device indicates an identifier of the first terminal device and/or an identifier of the second terminal device.

Example embodiment 72:

The method according to any of example embodiments 65-71, further comprising: receiving, from the first terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

Example embodiment 73: The method according to example embodiment 72, wherein when Uu link quality of the second terminal device is above a threshold configured by the network node, the second terminal device is capable of performing relaying to the network node for the first terminal device.

Example embodiment 74:

The method according to any of example embodiments 65-73, further comprising: receiving, from the first terminal device, information indicating whether the second terminal device selects a cell from a set of the candidate cells available for cell selection or reselection by the second terminal device.

Example embodiment 75:

The method according to example embodiment 74, wherein the set of the candidate cells include one or more of: a serving cell of the first terminal device; and one or more cells indicated by the network node.

Example embodiment 76:

The method according to any of example embodiments 65-75, further comprising: transmitting a paging message towards one or more relay devices paired to one or more remote devices served by the network node, wherein the paging message instructs the one or more relay devices to report corresponding Uu quality measurements. Example embodiment 77:

The method according to example embodiment 76, wherein the paging message includes one or more of: one or more identifiers of the one or more relay devices; one or more identifiers of the one or more remote devices; information indicating that the paging message is for Uu quality reporting only; and information about a list of cells for which Uu quality measurements need to be reported.

Example embodiment 78:

The method according to any of example embodiments 65-77, wherein the network node receives one or more of the following information in a small data transmission, SDT, procedure: at least part of pairing information of the second terminal device; and one or more Uu quality measurements of the second terminal device.

Example embodiment 79:

The method according to any of example embodiments 65-78, further comprising: determining which of the one or more devices paired to the first terminal device is to be selected as a relay device for the first terminal device, according to the at least part of the pairing information of the first terminal device and/or information reported to the network node by at least one of the one or more devices paired to the first terminal device.

Example embodiment 80:

The method according to example embodiment 79, further comprising: establishing an indirect path between the first terminal and the network node via the relay device selected for the first terminal device from the one or more devices by the network node.

Example embodiment 81:

A network node (500), comprising: one or more processors (501); and one or more memories (502) comprising computer program codes (503), the one or more memories (502) and the computer program codes (503) configured to, with the one or more processors (501), cause the network node (500) at least to: transmit, towards a first terminal device, configuration information for enabling or disabling at least partial reporting of pairing information of the first terminal device towards the network node, wherein the pairing information of the first terminal device is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and receive at least part of the pairing information which is reported by the first terminal device according to the configuration information.

Example embodiment 82:

The network node according to example embodiment 81, wherein the one or more memories and the computer program codes are configured to, with the one or more processors, cause the network node to perform the method according to any one of example embodiments 66-80.

Example embodiment 83 :

A network node, the network node being configured to: transmit, towards a first terminal device, configuration information for enabling or disabling at least partial reporting of pairing information of the first terminal device towards the network node, wherein the pairing information of the first terminal device is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and receive at least part of the pairing information which is reported by the first terminal device according to the configuration information.

Example embodiment 84:

The network node according to example embodiment 83, wherein the network node is further configured to perform the method according to any one of example embodiments 66-80.

Example embodiment 85:

A computer-readable medium having computer program codes (503) embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to any one of example embodiments 65-80.

Example embodiment 86:

A computer program or computer program product comprising program code to be executed by at least one processor of a network node, whereby execution of the program code causes the network node to perform the method according to any one of example embodiments 65-80.

Claims

1. A method (200) performed by a first terminal device, comprising: determining (202) pairing information of the first terminal device, wherein the pairing information is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and transmitting (204) at least part of the pairing information of the first terminal device towards a network node.

2. The method according to claim 1, wherein the pairing information of the first terminal device indicates one or more of: a number of the one or more devices; one or more identifiers of the one or more devices; and one or more serving cells of the one or more devices.

3. The method according to claim 2, wherein the one or more identifiers of the one or more devices include one or more of: one or more Uu identifiers of the one or more devices; one or more temporary identifiers of the one or more devices; and one or more local identifiers of the one or more devices.

4. The method according to claim 3, wherein the one or more temporary identifiers and/or the one or more local identifiers of the one or more devices are allocated by the first terminal device.

5. The method according to claim 3 or 4, wherein the one or more temporary identifiers comprise a cell-radio network temporary identifier, C-RNTI, an inactive- radio network temporary identifier, I-RNTI, and/or a paging-radio network temporary identifier, P-RNTI.

6. The method according to any of claims 1-5, further comprising: informing an identifier of the first terminal device and/or an identifier of the second terminal device to the second terminal device.

7. The method according to any of claims 1-6, further comprising: receiving information indicating an identifier of the second terminal device and/or a serving cell of the second terminal device from the second terminal device.

8. The method according to any of claims 1-7, further comprising: receiving, from the network node, configuration information for enabling or disabling at least partial reporting of the pairing information of the first terminal device towards the network node.

9. The method according to claim 8, wherein the configuration information is based at least in part on one or more the following factors: a demand of the network node; a state of a connection between the first terminal device and the network node; a state of connections between the one or more devices and the network node; link quality over Uu interface of an indirect path configured to the first terminal device; and link quality over Uu interface between the one or more devices and the network node.

10. The method according to any of claims 1-9, wherein the transmission of the at least part of the pairing information of the first terminal device towards the network node is enabled or disabled based at least in part on one or more the following factors: configuration information from the network node; a change of information about the one or more devices; capabilities of the one or more devices to perform relaying to the network node for the first terminal device; and a result of cell selection or reselection of the one or more devices.

11. The method according to any of claims 1-10, further comprising: receiving, from the second terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

12. The method according to any of claims 1-11, further comprising: transmitting, towards the network node, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

13. The method according to any of claims 1-12, further comprising: transmitting, to the second terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device.

14. The method according to claim 13, wherein the set of the candidate cells include one or more of: a serving cell of the first terminal device; and one or more cells indicated by the network node.

15. The method according to claim 13 or 14, further comprising: receiving, from the second terminal device, information indicating whether the second terminal device selects a cell from the set of the candidate cells.

16. The method according to any of claims 13-15, further comprising: transmitting, towards the network node, information indicating whether the second terminal device selects a cell from the set of the candidate cells.

17. The method according to any of claims 1-16, further comprising: establishing an indirect path between the first terminal and the network node via a relay device, wherein the relay device is selected from the one or more devices by the network node according to the at least part of the pairing information of the first terminal device and/or information reported to the network node by at least one of the one or more devices paired to the first terminal device.

18. A first terminal device (500), comprising: one or more processors (501); and one or more memories (502) comprising computer program codes (503), the one or more memories (502) and the computer program codes (503) configured to, with the one or more processors (501), cause the first terminal device (500) at least to: determine pairing information of the first terminal device, wherein the pairing information is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and transmit at least part of the pairing information of the first terminal device towards a network node.

19. The first terminal device according to claim 18, wherein the one or more memories and the computer program codes are configured to, with the one or more processors, cause the first terminal device to perform the method according to any one of claims 2-17.

20. A first terminal device, the first terminal device being configured to: determine pairing information of the first terminal device, wherein the pairing information is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and transmit at least part of the pairing information of the first terminal device towards a network node.

21. The first terminal device according to claim 20, wherein the first terminal device is further configured to perform the method according to any one of claims 2-17.

22. A computer-readable medium having computer program codes (503) embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to any one of claims 1-17.

23. A computer program or computer program product comprising program code to be executed by at least one processor of a first terminal device, whereby execution of the program code causes the first terminal device to perform the method according to any one of claims 1-17.

24. A method (300) performed by a second terminal device, comprising: determining (302) pairing information of the second terminal device which is a relaying capable device paired to a first terminal device, wherein the pairing information indicates an identifier of the second terminal device; and transmitting (302) information indicating the identifier of the second terminal device to the first terminal device.

25. The method according to claim 24, wherein the identifier of the second terminal device is a Uu identifier, a temporary identifier or a local identifier of the second terminal device.

26. The method according to claim 25, wherein the temporary identifier of the second terminal device comprises a C-RNTI, an I-RNTI, and/or a P-RNTI.

27. The method according to any of claims 24-26, further comprising: transmitting information indicating a serving cell of the second terminal device to the first terminal device.

28. The method according to any of claims 24-27, further comprising: determining whether the second terminal device is capable of performing relaying to the network node for the first terminal device; and transmitting, to the first terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

29. The method according to claim 28, wherein when Uu link quality of the second terminal device is above a threshold configured by the network node, the second terminal device determines that the second terminal device is capable of performing relaying to the network node for the first terminal device.

30. The method according to any of claims 24-29, further comprising: receiving, from the first terminal device, information indicating a set of candidate cells available for cell selection or reselection by the second terminal device.

31. The method according to claim 30, wherein the set of the candidate cells include one or more of: a serving cell of the first terminal device; and one or more cells indicated by a network node.

32. The method according to claim 30 or 31, further comprising: determining whether to select a cell from the set of the candidate cells; transmitting, to the first terminal device, information indicating whether the second terminal device selects the cell from the set of the candidate cells.

33. The method according to any of claims 24-32, further comprising: receiving a paging message from a network node, wherein the paging message instructs the second terminal device to report one or more Uu quality measurements of the second terminal device.

34. The method according to claim 33, wherein the paging message includes one or more of: an identifier of the first terminal device; an identifier of the second terminal device; information indicating that the paging message is for Uu quality reporting only; and information about a list of cells for which Uu quality measurements need to be reported.

35. The method according to any of claims 24-34, wherein the second terminal device transmits one or more of the following information towards the network node in a small data transmission, SDT, procedure: the at least part of the pairing information of the second terminal device; and one or more Uu quality measurements of the second terminal device.

36. A second terminal device (500), comprising: one or more processors (501); and one or more memories (502) comprising computer program codes (503), the one or more memories (502) and the computer program codes (503) configured to, with the one or more processors (501), cause the second terminal device (500) at least to: determine pairing information of the second terminal device which is a relaying capable device paired to a first terminal device, wherein the pairing information indicates an identifier of the second terminal device; and transmit information indicating the identifier of the second terminal device to the first terminal device.

37. The second terminal device according to claim 36, wherein the one or more memories and the computer program codes are configured to, with the one or more processors, cause the second terminal device to perform the method according to any one of claims 25-35.

38. A second terminal device, the second terminal device being configured to: determine pairing information of the second terminal device which is a relaying capable device paired to a first terminal device, wherein the pairing information indicates an identifier of the second terminal device; and transmit information indicating the identifier of the second terminal device to the first terminal device.

39. The second terminal device according to claim 38, wherein the second terminal device is further configured to perform the method according to any one of claims 25- 35.

40. A computer-readable medium having computer program codes (503) embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to any one of claims 24-35.

41. A computer program or computer program product comprising program code to be executed by at least one processor of a second terminal device, whereby execution of the program code causes the second terminal device to perform the method according to any one of claims 24-25.

42. A method (400) performed by a network node, comprising: transmitting (402), towards a first terminal device, configuration information for enabling or disabling at least partial reporting of pairing information of the first terminal device towards the network node, wherein the pairing information of the first terminal device is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and receiving (404) at least part of the pairing information which is reported by the first terminal device according to the configuration information.

43. The method according to claim 42, wherein the pairing information of the first terminal device indicates one or more of: a number of the one or more devices; one or more identifiers of the one or more devices; and one or more serving cells of the one or more devices.

44. The method according to claim 43, wherein the one or more identifiers of the one or more devices include one or more of: one or more Uu identifiers of the one or more devices; one or more temporary identifiers of the one or more devices; and one or more local identifiers of the one or more devices.

45. The method according to claim 44, wherein the one or more temporary identifiers comprise a cell-radio network temporary identifier, C-RNTI, an inactive-radio network temporary identifier, I-RNTI, and/or a paging-radio network temporary identifier, P- RNTI.

46. The method according to any of claims 42-45, wherein the configuration information is determined by the network node based at least in part on one or more the following factors: a demand of the network node; a state of a connection between the first terminal device and the network node; a state of connections between the one or more devices and the network node; link quality over Uu interface of an indirect path configured to the first terminal device; and link quality over Uu interface between the one or more devices and the network node.

47. The method according to any of claims 42-46, wherein the at least partial reporting of the pairing information of the first terminal device towards the network node is enabled or disabled also based at least in part on one or more the following factors: a change of information about the one or more devices; capabilities of the one or more devices to perform relaying to the network node for the first terminal device; and a result of cell selection or reselection of the one or more devices.

48. The method according to any of claims 42-47, further comprising: receiving at least part of pairing information of the second terminal device from the second terminal device, wherein the pairing information of the second terminal device indicates an identifier of the first terminal device and/or an identifier of the second terminal device.

49. The method according to any of claims 42-48, further comprising: receiving, from the first terminal device, information indicating whether the second terminal device is capable of performing relaying to the network node for the first terminal device.

50. The method according to claim 49, wherein when Uu link quality of the second terminal device is above a threshold configured by the network node, the second terminal device is capable of performing relaying to the network node for the first terminal device.

51. The method according to any of claims 42-50, further comprising: receiving, from the first terminal device, information indicating whether the second terminal device selects a cell from a set of the candidate cells available for cell selection or reselection by the second terminal device.

52. The method according to claim 51, wherein the set of the candidate cells include one or more of: a serving cell of the first terminal device; and one or more cells indicated by the network node.

53. The method according to any of claims 42-52, further comprising: transmitting a paging message towards one or more relay devices paired to one or more remote devices served by the network node, wherein the paging message instructs the one or more relay devices to report corresponding Uu quality measurements.

54. The method according to claim 53, wherein the paging message includes one or more of: one or more identifiers of the one or more relay devices; one or more identifiers of the one or more remote devices; information indicating that the paging message is for Uu quality reporting only; and information about a list of cells for which Uu quality measurements need to be reported.

55. The method according to any of claims 42-54, wherein the network node receives one or more of the following information in a small data transmission, SDT, procedure: at least part of pairing information of the second terminal device; and one or more Uu quality measurements of the second terminal device.

56. The method according to any of claims 42-55, further comprising: determining which of the one or more devices paired to the first terminal device is to be selected as a relay device for the first terminal device, according to the at least part of the pairing information of the first terminal device and/or information reported to the network node by at least one of the one or more devices paired to the first terminal device.

57. The method according to claim 56, further comprising: establishing an indirect path between the first terminal and the network node via the relay device selected for the first terminal device from the one or more devices by the network node.

58. A network node (500), comprising: one or more processors (501); and one or more memories (502) comprising computer program codes (503), the one or more memories (502) and the computer program codes (503) configured to, with the one or more processors (501), cause the network node (500) at least to: transmit, towards a first terminal device, configuration information for enabling or disabling at least partial reporting of pairing information of the first terminal device towards the network node, wherein the pairing information of the first terminal device is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and receive at least part of the pairing information which is reported by the first terminal device according to the configuration information.

59. The network node according to claim 58, wherein the one or more memories and the computer program codes are configured to, with the one or more processors, cause the network node to perform the method according to any one of claims 43-57.

60. A network node, the network node being configured to: transmit, towards a first terminal device, configuration information for enabling or disabling at least partial reporting of pairing information of the first terminal device towards the network node, wherein the pairing information of the first terminal device is related to one or more devices which are relaying capable devices paired to the first terminal device, and the one or more devices include at least a second terminal device; and receive at least part of the pairing information which is reported by the first terminal device according to the configuration information.

61. The network node according to claim 60, wherein the network node is further configured to perform the method according to any one of claims 43-57.

62. A computer-readable medium having computer program codes (503) embodied thereon which, when executed on a computer, cause the computer to perform any step of the method according to any one of claims 42-57.

63. A computer program or computer program product comprising program code to be executed by at least one processor of a network node, whereby execution of the program code causes the network node to perform the method according to any one of claims 42-57.