WO2023161431A1

WO2023161431A1 - Signaling and mechanisms for ue- or network-triggered mobility in multi-hop user-to-network (u2n) sidelink scenarios

Info

Publication number: WO2023161431A1
Application number: PCT/EP2023/054708
Authority: WO
Inventors: Adrián Lahuerta LAVIEJA; Jingya Li; Min Wang; Antonino ORSINO
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2022-02-25
Filing date: 2023-02-24
Publication date: 2023-08-31

Abstract

According to an aspect, there is provided a method for selecting at least one relay wireless device to provide an indirect connection path between a network node and a first wireless device via the at least one selected relay wireless device. The method comprises obtaining (502; 802) information relating to a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices. The plurality of direct communication links provide at least one candidate indirect connection path between the network node and the first wireless device. The method also comprises selecting (504; 804) at least one of the one or more candidate relay wireless devices to provide the indirect connection path between the network node and the first wireless device, wherein the selection is based on path information relating to the at least one candidate indirect connection paths that is determined from the obtained information.

Description

Signaling and Mechanisms for UE- or Network-Triggered Mobility in Multi-Hop User-to-Network (U2N) Sidelink Scenarios

TECHNICAL FIELD

This disclosure relates to mobility in multi-hop User-to-network (U2N) sidelink scenarios.

BACKGROUND

Sidelink transmissions in NR

Sidelink (SL) transmissions over New Radio (NR) are specified for Release (Rel.) 16. These are enhancements of the ProSe (PROximity-based SErvices) specified for Long Term Evolution (LTE). Four new enhancements are particularly introduced to NR sidelink transmissions as follows:

• Support for unicast and groupcast transmissions are added in NR sidelink. For unicast and groupcast, the physical sidelink feedback channel (PSFCH) is introduced for a receiver User Equipment (UE) to reply the decoding status to a transmitter UE.

• Grant-free transmissions, which are adopted in NR uplink transmissions, are also provided in NR sidelink transmissions, to improve the latency performance.

• To alleviate resource collisions among different sidelink transmissions launched by different UEs, it enhances channel sensing and resource selection procedures, which also lead to a new design of Physical Sidelink Common Control Channel (PSCCH).

• To achieve a high connection density, congestion control and thus the Quality of Service (QoS) management is supported in NR sidelink transmissions.

To enable the above enhancements, new physical channels and reference signals are introduced in NR (previously available in LTE):

• PSSCH (Physical Sidelink Shared Channel, the SL version of the Physical Downlink Shared Channel (PDSCH)): The PSSCH is transmitted by a sidelink transmitter UE, which conveys sidelink transmission data, system information blocks (SIBs) for radio resource control (RRC) configuration, and a part of the sidelink control information (SCI).

• PSFCH (Physical Sidelink Feedback Channel, the SL version of Physical Uplink Control Channel (PUCCH)): The PSFCH is transmitted by a sidelink receiver UE for unicast and groupcast, which conveys 1 -bit information over 1 resource block (RB) for the Hybrid Automatic Repeat Request (HARQ) acknowledgement (ACK) and the negative ACK (NACK). In addition, channel state information (CSI) is carried in the medium access control (MAC) control element (CE) over the PSSCH instead of the PSFCH.

• PSCCH (Physical Sidelink Common Control Channel, the SL version of Physical Downlink Control Channel (PDCCH)): When the traffic to be sent to a receiver UE arrives at a transmitter UE, a transmitter UE should first send the PSCCH, which conveys a part of SCI (Sidelink Control information, SL version of Downlink Control Information (DCI)) to be decoded by any UE for the channel sensing purpose, including the reserved time-frequency resources for transmissions, demodulation reference signal (DMRS) pattern and antenna port, etc.

• Sidelink Primary/Secondary Synchronization Signal (S-PSS/S-SSS): Similar to downlink (DL) transmissions in NR, in sidelink transmissions, primary and secondary synchronization signals (called S-PSS and S-SSS, respectively) are supported. Through detecting the S-PSS and S-SSS, a UE is able to identify the sidelink synchronization identity (SSID) from the UE sending the S-PSS/S-SSS. Through detecting the S- PSS/S-SSS, a UE is therefore able to know the characteristics of the UE transmitting the S-PSS/S-SSS. A series of processes of acquiring timing and frequency synchronization together with SSIDs of UEs is called initial cell search. Note that the UE sending the S-PSS/S-SSS may not be necessarily involved in sidelink transmissions, and a node (UE/eNB/gNB) sending the S-PSS/S-SSS is called a synchronization source. There are 2 S-PSS sequences and 336 S-SSS sequences forming a total of 672 SSIDs in a cell.

• Physical Sidelink Broadcast Channel (PSBCH): The PSBCH is transmitted along with the S-PSS/S-SSS as a synchronization signal/PSBCH block (SSB). The SSB has the same numerology as PSCCH/PSSCH on that carrier, and an SSB should be transmitted within the bandwidth of the configured bandwidth part (BWP). The PSBCH conveys information related to synchronization, such as the direct frame number (DFN), indication of the slot and symbol level time resources for sidelink transmissions, in-coverage indicator, etc. The SSB is transmitted periodically at every 160 ms.

• DMRS, phase tracking reference signal (PT-RS), channel state information reference signal (CSI-RS): These physical reference signals supported by NR downlink/uplink transmissions are also adopted by sidelink transmissions. Similarly, the PT-RS is only applicable for Frequency Range 2 (FR2) transmission.

Another new feature is the two-stage sidelink control information (SCI). This is a version of the DCI for SL. Unlike the DCI, only part (the first stage) of the SCI is sent on the PSCCH. This part is used for channel sensing purposes (including the reserved time-frequency resources for transmissions, demodulation reference signal (DMRS) pattern and antenna port, etc.) and can be read by all UEs while the remaining (second stage) scheduling and control information such as a 8-bit source identity (ID) and a 16-bit destination ID, New Data Indicator (NDI), Redundancy Version (RV) and HARQ process ID is sent on the PSSCH to be decoded by the receiver UE.

Similar as for ProSe in LTE, NR sidelink transmissions have the following two modes of resource allocations:

• Mode 1 : Sidelink resources are scheduled by a gNB.

• Mode 2: The UE autonomously selects sidelink resources from a (pre-)configured sidelink resource pool(s) based on the channel sensing mechanism.

For the in-coverage UE, a gNB can be configured to adopt Mode 1 or Mode 2. For the out-of-coverage UE, only Mode 2 can be adopted.

As in LTE, scheduling over the sidelink in NR is done in different ways for Mode 1 and Mode 2.

Mode 1 supports the following two kinds of grants: Dynamic grant: When the traffic to be sent over sidelink arrives at a transmitter UE, this UE should launch the four-message exchange procedure to request sidelink resources from a gNB (Scheduling Request (SR) on uplink (UL), grant, Buffer Status Reporting (BSR) on UL, grant for data on SL sent to UE). During the resource request procedure, a gNB may allocate a sidelink radio network temporary identifier (SL-RNTI) to the transmitter UE. If this sidelink resource request is granted by a gNB, then a gNB indicates the resource allocation for the PSCCH and the PSSCH in the downlink control information (DCI) conveyed by PDCCH with cyclic redundancy check (CRC) scrambled with the SL-RNTI. When a transmitter UE receives such a DCI, a transmitter UE can obtain the grant only if the scrambled CRC of DCI can be successfully solved by the assigned SL-RNTI. A transmitter UE then indicates the time-frequency resources and the transmission scheme of the allocated PSSCH in the PSCCH, and launches the PSCCH and the PSSCH on the allocated resources for sidelink transmissions. When a grant is obtained from a gNB, a transmitter UE can only transmit a single transport block (TB). As a result, this kind of grant is suitable for traffic with a loose latency requirement.

Configured grant: For the traffic with a strict latency requirement, performing the four-message exchange procedure to request sidelink resources may induce unacceptable latency. In this case, prior to the traffic arrival, a transmitter UE may perform the four-message exchange procedure and request a set of resources. If a grant can be obtained from a gNB, then the requested resources are reserved in a periodic manner. Upon traffic arriving at a transmitter UE, this UE can launch the PSCCH and the PSSCH on the upcoming resource occasion. In fact, this kind of grant is also known as grant-free transmissions.

In both dynamic grant and configured grant, a sidelink receiver UE cannot receive the DCI (since it is addressed to the transmitter UE), and therefore a receiver UE should perform blind decoding to identify the presence of PSCCH and find the resources for the PSSCH through the SCI.

When a transmitter UE launches the PSCCH, CRC is also inserted in the SCI without any scrambling.

In the Mode 2 resource allocation, when traffic arrives at a transmitter UE, this transmitter UE should autonomously select resources for the PSCCH and the PSSCH. To further minimize the latency of the feedback HARQ ACK/NACK transmissions and subsequently retransmissions, a transmitter UE may also reserve resources for PSCCH/PSSCH for retransmissions. To further enhance the probability of successful TB decoding at one shot and thus suppress the probability to perform retransmissions, a transmitter UE may repeat the TB transmission along with the initial TB transmission. This mechanism is also known as blind retransmission. As a result, when traffic arrives at a transmitter UE, then this transmitter UE should select resources for the following transmissions:

1) The PSSCH associated with the PSCCH for initial transmission and blind retransmissions.

2) The PSSCH associated with the PSCCH for retransmissions.

Since each transmitter UE in sidelink transmissions should autonomously select resources for above transmissions, how to prevent different transmitter UEs from selecting the same resources turns out to be a critical issue in Mode 2. A particular resource selection procedure is therefore imposed to Mode 2 based on channel sensing. The channel sensing algorithm involves measuring Reference Signal Received Power (RSRP) on different subchannels and requires knowledge of the different UEs power levels of DMRS on the PSSCH or the DMRS on the PSCCH depending on the configuration. This information is known only after receiver SCI launched by (all) other UEs. The sensing and selection algorithm is rather complex.

Layer 2 (L2) UE-to-Network (U2N) relay

In 3GPP TR 23.752 v17.0.0 "Study on system enhancement for Proximity based Services (ProSe) in the 5^th Generation (5G) System (5GS)” clause 6.7, the layer-2 based UE-to-Network (U2N) relay is described.

General information: In this clause, the protocol architecture supporting a L2 UE-to-Network Relay UE is provided.

The L2 UE-to-Network Relay UE provides forwarding functionality that can relay any type of traffic over the PC5 link.

The L2 UE-to-Network Relay UE provides the functionality to support connectivity to the 5GS for Remote UEs. A UE is considered to be a Remote UE if it has successfully established a PC5 link to the L2 UE-to-Network Relay UE. A Remote UE can be located within NG-RAN coverage or outside of NG-RAN coverage.

Fig. 1 illustrates the protocol stack for the user plane transport, related to a PDU [Protocol Data Unit] Session, including a Layer 2 UE-to-Network Relay UE. The PDU layer corresponds to the PDU carried between the Remote UE and the Data Network (DN) over the PDU session. It is important to note that the two endpoints of the PDCP [Packet Data Convergence Protocol] link are the Remote UE and the gNB. The relay function is performed below PDCP. This means that data security is ensured between the Remote UE and the gNB without exposing raw data at the UE-to-Network Relay UE. Fig. 1 corresponds to Figure A.2.1-1 : User Plane Stack for L2 UE-to-Network Relay UE in 3GPP TR 23.752.

The adaptation relay layer within the UE-to-Network Relay UE can differentiate between signalling radio bearers (SRBs) and data radio bearers (DRBs) for a particular Remote UE. The adaption relay layer is also responsible for mapping PC5 traffic to one or more DRBs of the Uu. The definition of the adaptation relay layer is under the responsibility of RAN WG2 in 3GPP.

Fig. 2 illustrates the protocol stack of the Non-Access Stratum (NAS) connection for the Remote UE to the NAS- Mobility Management (NAS-MM) and NAS-Session Management (NAS-SM) components. The NAS messages are transparently transferred between the Remote UE and 5G access network 5G-AN over the Layer 2 UE-to-Network Relay UE using:

PDCP end-to-end connection where the role of the UE-to-Network Relay UE is to relay the PDUs over the signalling radio bear without any modifications.

N2 connection between the 5G-AN and AMF over N2.

N3 connection AMF and SMF over N11 .

The role of the UE-to-Network Relay UE is to relay the PDUs from the signalling radio bearer without any modifications. Fig. 2 is a copy of Figure A.2.2-1 : Control Plane for L2 UE-to-Network Relay UE in 3GPP TR 23.752.

Relay establishment procedure: The Remote UE needs to establish its own PDU sessions/DRBs with the network before user plane data transmission.

PC5-RRC aspects of Rel-16 NR Vehicle-to-everything (V2X) PC5 unicast link establishment procedures can be reused to setup a secure unicast link between Remote UE and Relay UE for L2 UE-to-Network relaying before the Remote UE establishes a Uu RRC connection with the network via Relay UE.

For both in-coverage and out-of-coverage cases, when the Remote UE initiates the first RRC message for its connection establishment with gNB, the PC5 L2 configuration for the transmission between the Remote UE and the UE-to-Network Relay UE can be based on the RLC/MAC configuration defined in specifications.

The establishment of Uu SRB1/SRB2 and DRB of the Remote UE is subject to legacy Uu configuration procedures for L2 UE-to-Network Relay.

Fig. 3 illustrates a high level connection establishment procedure that applies to L2 UE-to-Network Relay. Fig. 3 is a copy of Figure 16.12.5.1-1 : Procedure for L2 U2N remote UE connection establishment in 3GPP TS 38.300 V17.3.0.

Step 1. The Remote and Relay UE perform the discovery procedure, and establish a PC5-RRC connection using the legacy Rel-16 procedure as a baseline.

Step 2. The Remote UE sends the first RRC message (i.e. , RRCSetupRequest) for its connection establishment with gNB via the Relay UE, using a default L2 configuration on PC5. The gNB responds with an RRCSetup message to Remote UE. The RRCSetup delivery to the Remote UE uses the default configuration on PC5. If the relay UE had not started in RRC_CONNECTED, it would need to do its own connection establishment as part of this step. The details for Relay UE to forward the RRCSetupRequestl RRCSetup message for Remote UE at this step can be discussed in Wl phase.

Step 3. The gNB and Relay UE perform relaying channel setup procedure over Uu. According to the configuration from gNB, the Relay/Remote UE establishes an RLC channel for relaying of SRB1 towards the Remote UE over PC5. This step prepares the relaying channel for SRB1 .

Step 4. Remote UE SRB1 message (e.g. an RRCSetupComplete message) is sent to the gNB via the Relay UE using SRB1 relaying channel over PC5. Then the Remote UE is RRC connected over Uu.

Step 5. The Remote UE and gNB establish security following legacy procedure and the security messages are forwarded through the Relay UE.

Step 6. The gNB sets up additional RLC channels between the gNB and Relay UE for traffic relaying. According to the configuration from gNB, the Relay/Remote UE sets up additional RLC channels between the Remote UE and Relay UE for traffic relaying. The gNB sends an RRCReconfiguration to the Remote UE via the Relay UE, to set up the relaying SRB2/DRBs. The Remote UE sends an RRCReconfigurationComplete to the gNB via the Relay UE as a response. Besides the connection establishment procedure, for L2 UE-to-Network relay:

The RRC reconfiguration and RRC connection release procedures can reuse the legacy RRC procedure, with the message content/configuration design left to Wl phase.

The RRC connection re-establishment and RRC connection resume procedures can reuse the legacy RRC procedure as baseline, by considering the above connection establishment procedure of L2 UE-to- Network Relay to handle the relay specific part, with the message content/configuration design left to Wl phase.

SUMMARY

There currently exist certain challenge(s). As explained in the above section "L2 UE-to-Network relay”, in the current NR standard, a remote UE performs sidelink discovery and sidelink relay establishment procedures when one of the following conditions is met:

• based on the quality of the existing PC5 links in terms of metrics (e.g., SL-RSRP or SL discovery RSRP - SD-RSRP) for the remote UE which is out of coverage from any gNB. Any PC5 link in the measurement contains only one hop.

• based on the quality of the Uu link between the remote UE and a gNB in terms of metrics e.g., RSRP, Reference Signal Received Quality (RSRQ), Received Signal Strength Indicator (RSSI), Signal to Interference Noise Ratio (SINR), Signal to Interference Ratio (SIR), etc for the remote UE which has network coverage to a gNB.

In a multi-hop sidelink relaying-assisted network, there may be cases where the direct link between a remote UE and a relay UE is good, but the rest of the wireless links between the relay UE and its destination node (another relay UE or a gNB) is bad. In these cases, the existing sidelink discovery and relay establishment procedure can result in a bad end-to-end (E2E) wireless path selection for the remote UE since the procedure only considers per hop metrics, and thereby reducing the success rate and increasing the latency of its sidelink relay establishment.

This is because the network may be only aware of what is happening in the direct Uu link towards the remote UE but may not be aware of the quality of the link(s) between the remote UE and one (or more) relay UE(s). The current framework, standardized during Rel-17, implies that measurements are performed by the UE per-hop, and thus there is no estimation of the overall quality of the relay UE that includes the PC5 and Uu hops.

Also, according to the agreements in Rel-17, a remote UE performs cell/relay selection and reselection and sidelink discovery only based on the channel quality over the PC5 link with the relay UE. This is not particularly efficient since the remote UE is not aware of what the channel quality is over a Uu link of a relay UE towards the network. In fact, even if the remote UE performs several sidelink procedures to establish a better and stable sidelink relay connection towards the network, the remote UE may incur in several reconfigurations, handovers, and path switches due to the fact that the Uu link between the relay UE and the network may not as good as the PC5 link between the remote UE and the relay UE. Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges. These solutions can be divided into two alternative solutions, a network-triggered solution and a UE-triggered solution, which can be implemented independently of each other.

Network-triggered solution

New behaviours and signalling for a remote UE are disclosed. A remote UE can perform a sidelink discovery procedure and/or a sidelink relay establishment procedure following instructions from a network node which are transmitted to the remote UE via one or several relay UEs. For this, the remote UE can provide the network node with measurement reports which are transmitted to the network node via one or several relay UEs.

New behaviours and signalling for a relay UE are also disclosed. A relay UE can provide information to a network node, a remote UE, or to another relay UE, to assist a remote UE in performing a sidelink discovery procedure and/or a sidelink relay establishment procedure. The relay UE can provide both the network node (or to the relay nodes/UEs between the relay node/UE and the network node if any) with sidelink-related information and the remote UE (or to the relay nodes between the relay node and the remote UE if any) with instructions from the network node.

New behaviours and signalling for a network node (e.g. gNB or eNB) are also disclosed. A network node can receive and decode sidelink-related information from a relay UE to assist a remote UE in performing a sidelink discovery procedure and/or a sidelink relay establishment procedure. The network node can, based upon the information received via relay UEs, decide which relay node the remote UE shall connect to. The decision can be based on current or predicted information about the quality, performance, and/or configuration of the end-to-end (E2E) wireless sidelink link between the network node and the remote UE via relay UEs (at least one).

Thus, the disclosure of the network-triggered solution provides new behaviours and signalling from a network node and from a relay UE to assist a remote UE in performing sidelink discovery and/or sidelink relay establishment procedures. The provided new behaviour/signalling captures the information about the end-to-end wireless link between the network node and the remote UE. The decision can be made by the network node and transmitted to the remote UE via one or more relay UEs.

Certain embodiments of the network-triggered solution may provide one or more of the following technical advantage(s). The proposed solution enables a remote UE to use a good end-to-end wireless path when instructed by the network node to perform discovery or relay establishment procedures to establish a sidelink relay connection.

UE-triggered solution

New behaviours and signalling for a relay UE are disclosed. A relay UE can provide information for assisting a remote UE to perform a sidelink discovery procedure and a relay establishment procedure in a sidelink-relaying- assisted network. The information can contain current or predicted information about the quality, performance, and/or configuration of the end-to-end wireless link that the relay UE is associated to. New behaviours and signalling for a remote UE are also disclosed. The remote UE can perform a sidelink discovery procedure and a relay establishment procedure considering the quality/performance/configuration of all the candidate end-to-end wireless links, utilizing the new behaviours and signalling information received from candidate relay UE(s). This means that the remote UE can consider the qual ity/performance/configuration of each individual link that would be present if a multi-hop sidelink relay connection is established.

New behaviours and signalling for a network node are also disclosed. The network node can provide information for assisting a remote UE to perform a sidelink discovery procedure and a relay establishment procedure in a sidelink-relaying-assisted network. The information can contain current or predicted information about the quality, performance, and/or configuration of end-to-end wireless links between the remote UE and the network node involving one or more relay UEs.

Thus, the proposed solution involves new or modified signalling from relay UEs. The signalling can include information to assist a remote UE to obtain/derive at least one end-to-end wireless-link-quality metric that is used for its decision making within the discovery and relay establishment procedures. Consequently, new behaviours are expected at the remote UE side: the remote UE needs to know where to find the information, process it, and decide which network node to select.

Certain embodiments may provide one or more of the following technical advantage(s). The proposed solution enables a remote UE to select a good end-to-end wireless path when performing discovery and relay establishment procedures to establish a sidelink relay connection.

Compared to the existing procedures, the proposed network-triggered and UE-triggered solutions can help avoid a remote UE selecting a 'bad' end-to-end wireless path from the beginning, by dealing with the issue in a more proactive way. It can also reduce the latency and unnecessary signalling overhead if a remote UE anyway needs to be redirected/handed over to another access node and/or relay UE due to intermediate link quality issues.

More generally, the present disclosure provides the following aspects.

According to a first aspect, there is provided a method for selecting at least one relay wireless device to provide an indirect connection path between a network node and a first wireless device via the at least one selected relay wireless device. The method comprises obtaining information relating to a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices, wherein the plurality of direct communication links provide at least one candidate indirect connection path between the network node and the first wireless device; and selecting at least one of the one or more candidate relay wireless devices to provide the indirect connection path between the network node and the first wireless device, wherein the selection is based on path information relating to the at least one candidate indirect connection paths that is determined from the obtained information. According to a second aspect, there is provided a method performed by a wireless device. The method comprises obtaining path information relating to at least one candidate indirect connection path between a network node and a first wireless device via one or more relay wireless devices. Each candidate indirect connection path comprises a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices. The method further comprises providing the obtained information to the network node or the first wireless device.

According to a third aspect, there is provided a computer program product comprising a computer readable medium having computer readable code embodied therein, the computer readable code being configured such that, on execution by a suitable computer or processor, the computer or processor is caused to perform the method according to the first aspect, the second aspect, or any embodiments thereof.

According to a fourth aspect, there is provided a wireless device configured to perform the method according to the first aspect, the second aspect, or any embodiments thereof.

According to a fifth aspect, there is provided a wireless device comprising a processor and a memory, said memory containing instructions executable by said processor whereby said wireless device is operative to perform the method according to the first aspect, the second aspect, or any embodiments thereof.

According to a sixth aspect, there is provided a network node configured to perform the method according to the first aspect, the second aspect, or any embodiments thereof.

According to a seventh aspect, there is provided a network node comprising a processor and a memory, said memory containing instructions executable by said processor whereby said network node is operative to perform the method according to the first aspect, the second aspect, or any embodiments thereof.

BRI EF DESCRIPTION OF THE DRAWINGS

Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings, in which:

Fig. 1 is a copy of Figure A.2.1-1 : User Plane Stack for L2 UE-to-Network Relay UE in 3GPP TR 23.752;

Fig. 2 is a copy of Figure A.2.2-1 : Control Plane for L2 UE-to-Network Relay UE in 3GPP TR 23.752;

Fig. 3 is a diagram illustrating a procedure for remote UE connection establishment;

Fig. 4 a network in which UE-to-network sidelink multi-hop can be used to enable a remote UE to communicate with a network;

Fig. 5 is a flow chart illustrating a method performed by a network node according to an embodiment of the network-triggered solutions;

Fig. 6 is a flow chart illustrating a method performed by a first wireless device/remote UE according to an embodiment of the network-triggered solutions;

Fig. 7 is a flow chart illustrating a method performed by a first relay wireless device/relay UE according to an embodiment of the network-triggered solutions; Fig. 8 is a flow chart illustrating a method performed by a first wireless device/remote UE according to an embodiment of the UE-triggered solutions;

Fig. 9 is a flow chart illustrating a method performed by a second wireless device/relay UE according to an embodiment of the UE-triggered solutions;

Fig. 10 is a flow chart illustrating a method performed by a network node according to an embodiment of the UE-triggered solutions;

Fig. 11 shows an example of a communication system in accordance with some embodiments;

Fig. 12 shows a UE in accordance with some embodiments;

Fig. 13 shows a network node in accordance with some embodiments;

Fig. 14 is a block diagram illustrating a virtualization environment in which functions implemented by some embodiments may be virtualized; and

Fig. 15 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

Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

Although the embodiments are described herein in the context of the radio access technology (RAT) being NR, i.e. a remote UE and a relay UE use NR communication techniques, it will be appreciated that the embodiments are also applicable to single- or multi-hop relay scenarios where the link between a remote UE and a relay UE, and/or the link between two relay UEs, and/or the link between a relay UE and the base station may be based on LTE sidelink, NR sidelink, or a subsequent generation (e.g. 6^th Generation - 6G) sidelink. This can mean that the Uu connection between a relay UE and a base station (eNB or gNB as appropriate) may be LTE Uu or NR Uu. The connection between relay UEs and/or the connection between a remote UE and a relay UE is also not limited to sidelink (e.g. NR sidelink or LTE sidelink). Any short-range communication technology such as WiFi, Zigbee or Bluetooth, etc. could be used instead. The disclosed embodiments can also be applied to a relay scenario where the relay UE is configured with multiple connections to the RAN (i.e. the number of connections is equal to or larger than two), e.g. using dual connectivity (DC), carrier aggregation (CA), etc.

As used herein, the term "Remote UE” or "RM UE” refers to the that is able to transmit/receive packets from/to the gNB via an intermediate mobile terminal (the UE-to-NW relay UE) that is referred to herein as the "Relay UE” or "RL UE”. The term "candidate relay UE” or "candidate RL UE” is generally used herein to refer to a UE that could be used as a relay UE by the remote UE and network node.

The link or radio link over which the signals are transmitted between at least two UEs for device-to-device (D2D) operation is called herein as the sidelink (SL). The signals transmitted between the UEs for D2D operation are referred to herein as SL signals. Any of the terms "D2D link”, "V2X link”, "prose link”, "peer-to-peer (P2P) link”, "PC5 link” etc. can be used interchangeably with SL. The SL signals may also interchangeably be referred to as "V2X signals”, "D2D signals”, "prose signals”, "PC5 signals”, "peer-to-peer signals”, etc. More generally, the terms "communication link” and "direct communication link” are used herein to refer to a sidelink, D2D link, or a conventional direct connection between a UE and a network node (base station, e.g. an eNB or gNB).

Further, while specific embodiments described herein target sidelink relay scenarios, the methods and solutions described herein can also be applied, without any loss of meaning, to normal sidelink operation where two UEs are involved in sidelink operation, with or without the involvement on the network.

As noted above, the term "direct communication link” is used herein to represent a direct connection from a remote UE to a gNB (e.g. via a NR air interface), or a single 'hop' between two UEs. The term "indirect connection path” (also referred to as the "end-to-end path” or "multi-hop path”) is used herein to represent an indirect connection between a remote UE and a gNB via one or more intermediate nodes - the relay UE(s). As such, an indirect communication path between a remote UE and a network node is the comprised of two or more communication links, involving one or more relay UEs.

Fig. 4 illustrates a network in which UE-to-network sidelink multi-hop can be used to enable a remote UE to communicate with a network.

Fig. 4 shows an Access Node (AN), e.g. a gNB or eNB, that has a fiber connection to the core network (not shown). The AN controls a cell that provides network coverage for UEs. Four UEs are shown, with two of those UEs being within the cell coverage of the AN. One of the UEs (labelled Remote UE) outside the coverage of the cell wants to connect to the AN. The Remote UE performing discovery and relay establishment finds Candidate Relay UE2 (which is also outside the coverage of the cell), and Candidate Relay UE3 (which is inside the coverage of the cell) as potential relay UEs. Relay UE3 would be part of a UE-to-network scenario, and Relay UE2 would be part of a UE-to-UE sidelink multi-hop scenario. According to the new behaviours and signalling proposed herein, Relay UE2 and Relay UE3 inform the remote UE of the quality of the sidelink links. The remote UE may acquire such information during the discovery procedure or any other procedure performed before the sidelink relay establishment, and based on these link-quality parameters, it may select a suitable relay UE, e.g., Relay UE3.

Network-triggered solution

The following description and the flow charts in Figs. 5-7 relate to the network-triggered solution.

From a network standpoint, new behaviours and signalling need to be considered such that a remote UE is both: 1) configured to perform measurements (e.g. periodically) on the sidelink links and configured to report the results back to the network, and 2) provided with network-decided information related to the sidelink link and relay UE that the remote UE shall select. In deciding which sidelink link that the remote UE shall select, the network takes into account the end-to-end multi-hop sidelink link quality/performance in the link between the network node to the remote UE via one or several relay UEs in the multi-hop sidelink scenario such that the remote UE selects the best end-to-end path. As used herein, the link quality /performance information may include or comprise measurements of one or more link quality and/or performance parameters.

From a relay UE standpoint, new behaviours and signalling need to be considered such that the network node and the remote UE exchange the required information, e.g. so that the network node receives information about the quality or performance of the multi-hop sidelink link(s) between the remote UE and the network node such that the network node is able to make a decision based on the end-to-end path quality between the remote UE and the network node. The decision is related to which relay UE the remote UE should connect to.

According to some embodiments, a remote UE can receive configuration instructions from the network either directly from the network and stored by the UE for future use, or via relay UE(s). Furthermore, the remote UE may perform periodic measurements according to the configuration information received and report the results back to the network, either directly or via relay UE(s).

The quality or performance metric for the full end-to-end path can be determined by combining the per-link information for the direct communication links in the indirect connection path. Thus, in some embodiments the end- to-end perspective is achieved by combining current or predicted per-link quality /performance information of: 1) the Uu link between the gNB and the first (if more than one) relay UE, 2) all the PC5 links between relay UEs (if there is more than one relay UE in the indirect connection path) and the candidate relay UE, and 3) the PC5 link between the candidate relay UE and the remote UE.

The quality or performance metric for the full end-to-end path can be determined by any node that has the required information available for the links in the end-to-end path. In some embodiments the remote UE determines the quality or performance metric for the full end-to-end path and sends it to the network node either directly if a Uu communication link is established between the network node and the remote UE or via one or more relay UEs. In other embodiments, one of the relay UEs may determine the quality or performance metric for the full end-to-end path and then send this to the network node (optionally via one or more relay UEs). In other embodiments, the network node obtains the required information and determines the quality or performance metric for the full end-to- end path.

Per-link information can be expressed in terms of one or more quality or performance indicators, e.g., an RSRP value, an RSRQ value, a Signal to Noise Ratio (SNR) value, a SINR, a latency value, a capacity value (e.g. that captures or relates to both SNR and bandwidth), a congestion value, an energy status value, etc.

A quality or performance metric can be determined for the full end-to-end path by combining the per-link information for the direct communication links in the indirect connection path. The quality/performance metrics can be based on any of, e.g., a minimum value, a maximum value, a mean value, a weighted average value, a harmonic mean value, etc. of the per-link information.

Finally, the relay UE may share the above-mentioned information (the per-link information or the full path information) with the network node using either a set of per-link quality/performance indicators or a metric capturing the performance of the multi-hop sidelink link from network to the candidate relay UE. For example, in the scenario depicted in Fig. 4, in the case of candidate relay UE2, candidate relay UE2 is connected to the core network via a PC5 link between candidate relay UE2 and candidate relay UE1, and a Uu link between candidate relay UE1 and the AN/network node. Hence, the remote UE can share information (e.g. measurements) related to the PC5 link (between the remote UE and relay UE2) with relay UE2. Then, relay UE2 can share this information, together with information related to the PC5 link between relay UE2 and relay UE1, with relay UE1. Finally, relay UE1 can share all this information, plus information related to the Uu link between relay UE1 and the network node with the network node. In this way, the network node has information available for the end-to-end multi-hop sidelink path with the remote UE via relay UE1 and relay UE2.

In the scenario depicted in Fig. 4, the remote UE may also share information related to the PC5 link between remote UE and relay UE3 with relay UE3. Then, relay UE3 can share this information, plus information about the Uu link between relay UE3 and relay UE2, with the network node. In this way, the network node has information available for the end-to-end multi-hop sidelink path with the remote UE via relay UE3.

Now that the network node has information related to both candidate multi-hop sidelink paths, the network node can make a decision using an end-to-end criteria for which (candidate) relay UE in the example, i.e., relay UE2 or relay UE3, the remote UE should connect to. Once it has been decided, the network node transmits the decision/instructions to the remote UE using at least one of the multi-hop sidelink paths available.

For network nodes, relay UEs, and remote UEs to carry out the described procedures and methods, new behaviours and signalling are required by all the members involved.

In an embodiment, new behaviours and signalling from a network node can be provided for 1) configuring a remote UE to measure and report sidelink-related measurement results back to the network either directly or via relay UE(s), and 2) instructing the remote UE which relay UE the remote UE shall connect to.

In some embodiments, information (e.g. measurements) transmitted from the remote UE may be transmitted to the network node, either by the remote UE (if the remote UE is in coverage of the network node), or by a relay UE, both in in-coverage and out-of-coverage cases. The same applies for signalling from the network node to the remote UE (for example when signalling the decision from the network node on which relay UE(s) the remote UE is to use).

In an embodiment, new behaviours and signalling from a network node can be provided for configuring a relay UE to measure and report sidelink-related measurement results back to the network node, either directly or via other relay UE(s). The signalling can include information related to individual direct communication links between UEs, and/or related to the end-to-end performance/quality of a multi-hop sidelink path.

In an embodiment, new behaviours and signalling from a network node can be provided for instructing either the remote UE and/or relay UE to perform end-to-end or per-link measurements.

In some embodiments, the network node may instruct the remote UE and/or the relay UE to collect all the per-link measurements and obtain the end-to-end measurements from those per-link measurements and send them to the network node. a. In an example, only one of them (I ,e. , either the remote UE or the relay UE) will do the reporting, since their SL measurement results may be similar as they are close to each other. This approach avoids both the remote UE and relay UE reporting the same end-to-end measurements, thereby reducing unnecessary signalling overhead. b. In an example, both of them will do the reporting to the network node. In this way, the network node (e.g. gNB) may combine the information (measurement results) from both UEs to give better accuracy. Alternatively, the network node/gNB may select best measurement results from both UEs.

In an embodiment, new behaviours and signalling from a relay UE can be provided to receive and/or to decode instructions from the network node and proceed as instructed, e.g., measuring direct communication link quality/performance and reporting back to the network node, transmitting sidelink link decision information to remote UE(s) either directly or via other relay UE(s) that are part of the indirect connection path, if any.

In an embodiment, new behaviours and signalling from a remote UE can be provided to receive and/or decode instructions from the network node and proceed as instructed, e.g., measuring direct communication link quality/performance and reporting back to the network node either directly or via relay UE(s), and to connect to a relay UE that has been determined or decided by the network node.

The following embodiments relate to the manners in which a network node can communicate a measurement configuration to the relay UEs and/or the remote UE, and/or communicate a decision on which relay UE(s) to use for an indirect connection path. Thus, when the network node transmits the configuration and/or decision directly to the remote UE, it may be transmitted in messages such as system information (SI) messages, , e.g., in a SI block (SIB), or a Master Information Block (MIB).

In other embodiments, the configuration and/or decision can be transmitted by the network node using RRC signalling. In other embodiments, the configuration and/or decision can be transmitted by the network node using a MAC CE. In yet other embodiments, the configuration and/or decision can be transmitted by the network node using a control PDU of the adaptation layer (only in case of sidelink relay). In yet other embodiments, the configuration and/or decision can be transmitted by a PHY layer signalling (e.g., DCI on PDCCH).

In embodiments where the configuration and/or decision is transmitted by the network node to the remote UE via one or more relay UEs, the network node may transmit this information in, messages such as SI message e.g., in a SIB or MIB.

In embodiments where the configuration and/or decision is transmitted by the network node to the remote UE via one or more relay UEs, the network node may transmit this information to the relay UE using any of RRC signalling, a MAC CE, a control PDU of the adaptation layer (only in case of sidelink relay), and PHY (physical) layer signalling (e.g., DCI).

In embodiments where the information is transmitted by the network node to the remote UE via one or more relay UEs, after the relay UE has read/decoded this information, the relay UE can forward this information to the remote UE in, e.g., a discovery message used as part of a sidelink discovery procedure, or in one or more SIB messages. Alternatively, the relay UE can forward this information to the remote UE in a dedicated manner, for example using any of a PC5-RRC message, a MAC CE, a control PDU of the adaptation layer, or PHY layer signalling (e.g., SCI).

In embodiments where the information is transmitted by the network node to the remote UE via multiple relay UEs, the relay UEs can exchange this information with each other (until reaching the relay UE that will connect to the remote UE) using SI messages, e.g., one or more SIBs.

In some embodiments, information related to the end-to-end performance/quality of a multi-hop sidelink relay link, or information related to the performance/quality of the individual direct communication links in the end-to-end path is transmitted either from the remote UE directly to the network node or via one or more relay UE(s), or from relay UE(s) to the network node via one or more other relay UE(s). The transmitted performance/quality information can involve at least one value of the following parameters: a. RSRP, RSRQ, SNR, and/or SINR value(s) indicating the quality of the wireless backhaul links (e.g. the Uu communication links) that are used for connecting the candidate relay node to the core network. b. A latency indicator, e.g., a quantized value of latency, a congestion indicator. c. A capacity indicator (e.g. capturing or relating to SNR and bandwidth). d. A priority indicator, to indicate the priority level of the associated end-to-end multi-hop sidelink path, e.g., whether the traffic over this end-to-end multi-hop sidelink path will be treated with higher priority compared to other paths. e. An energy status indicator, to indicate the current energy conditions of the relay UEs involved in this end-to-end multi-hop sidelink path. For instance, if one of the relay UEs involved in the end-to-end path is about to run out of power (e.g. it has a low battery), a flag can be sent to the remote UE so that it will not select this path in case it has large traffic demands or critical data to be sent.

In some embodiments, any of the above parameter values comprised in the information transmitted to the network node may be shared with the network node either per link, i.e., one parameter value/indicator per link for each direct communication link between the candidate relay UE and the network node, or using a quality/performance metric for the full multi-hop sidelink path.

In embodiments, any of the above parameter values comprised in the information transmitted to the network node can be any of a minimum value of the parameter for the link or end-to-end path, a maximum value of the parameter for the link or end-to-end path, a mean value of the parameter for the link or end-to-end path, a weighted average value of the parameter for the link or end-to-end path, and a harmonic mean value of the parameter for the link or end-to-end path.

In some embodiments, if any of the above parameter values relate to individual direct communication links, the network node may perform a calculation or derivation using the received parameter values to decide which candidate relay UE the remote UE should connect to. The calculation or derivation by the network node can comprise determining any of a minimum value, a maximum value, a mean value, a weighted average value, a harmonic mean value.

In some embodiments, any of the above parameter values can be expressed using a linear scale or (if applicable) a logarithmic scale.

In some embodiments, the multi-hop sidelink quality/performance metric that the network node uses to decide which relay UE the remote UE should connect to can be any of, e.g., a minimum value, a maximum value, a mean value, a weighted average value, a harmonic mean value.

In some embodiments, the multi-hop sidelink quality/performance metric calculated by the network node can be expressed in terms of linear values or (if applicable) logarithmic values.

In some embodiments of the techniques described herein, the remote UE may perform an initial relay selection based on the PC5 link of the discovery message in the sidelink discovery procedure to find a suitable relay to connect to. Then the remote UE can perform a relay UE reselection that considers (or follows) the decision from the network node indicating a relay UE to use. According to the techniques described herein, the network node's decision will be based on the end-to-end performance of the multi-hop sidelink path, i.e. , the Uu link and all the PC5 links.

In some embodiments, if the remote UE has not received a specific instruction regarding the procedures above, the remote UE can proceed according to a default behaviour.

In some embodiments, the remote UE and/or relay UE(s) can be configured by the network with one or multiple measurement configurations. The measurement configurations may comprise any of: a. At least one measurement configuration that provides the relay UE or remote UE with a configuration regarding how to measure direct communication links and/or indirect connection paths in terms of at least one multi-hop/E2E metric; b. At least one measurement configuration provides the relay UE or remote UE with a configuration regarding how to measure direct communication links and/or indirect connection paths in terms of one or multiple per-hop (per-link) metrics, and to derive multi-hop measurements based on per-hop measurements. In some embodiments, on reception of one or multiple measurement configurations, the relay UE and/or remote UE performs measurements of links and/or paths, including serving paths and non-serving paths. The measurement can be in terms of at least one of the following metrics: one or multiple multi-hop/E2E metrics, and one or multiple per-hop metrics (from which multi-hop/E2E measurements are derived from the per-hop measurements).

In some embodiments, the relay UE and/or remote UE performs measurements periodically, in response to an event (i.e. event triggered), or on reception of a request message from the gNB or from another UE.

In some embodiments, the network node may explicitly indicate to the remote UE and/or relay UE if they need to report directly the end-to-end path measurement/metric or per-link measurement(s). In case the network node indicates that the remote UE and/or relay UE should report only the per-link measurements, the computation to obtain the end-to-end measurement/metric is at the network side.

Fig. 5 is a flow chart illustrating another method according to various embodiments performed by a network node/base station/eN B/g NB. The network node is for selecting at least one relay wireless device to provide an indirect connection path between the network node and a first wireless device via the at least one selected relay wireless device. The method may be performed by a network node (e.g. the network node 1110 or network node 1300 as described later with reference to Fig. 11 and 13 respectively). The network node may perform the method in response to executing suitably formulated computer readable code. The computer readable code may be embodied or stored on a computer readable medium, such as a memory chip, optical disc, or other storage medium. The computer readable medium may be part of a computer program product.

The method begins at step 502 with the network node obtaining information relating to a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices. The plurality of direct communication links provide at least one candidate indirect connection path between the network node and the first wireless device.

In step 504, the network node selects at least one of the one or more candidate relay wireless devices to provide the indirect connection path between the network node and the first wireless device. The selection is based on path information relating to the at least one candidate indirect connection paths that is determined from the obtained information.

In step 506, the network node provides an indication of the at least one selected relay wireless device to the first wireless device.

Fig. 6 is a flow chart illustrating a method according to various embodiments performed by a first wireless device/remote UE. The method may be performed by a UE or wireless device (e.g. the UE 1112 or UE 1200 as described later with reference to Figs. 11 and 12 respectively). The first wireless device may perform the method in response to executing suitably formulated computer readable code. The computer readable code may be embodied or stored on a computer readable medium, such as a memory chip, optical disc, or other storage medium. The computer readable medium may be part of a computer program product.

The method begins at step 602 with the first wireless device obtaining path information relating to at least one candidate indirect connection path between a network node and the first wireless device via one or more relay wireless devices. Each candidate indirect connection path comprises a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices.

In step 604 the first wireless device provides the obtained information to the network node.

Fig. 7 is a flow chart illustrating another method according to various embodiments performed by a first relay wireless device/relay UE. The first relay wireless device is capable of providing an indirect connection path between a network node and a first wireless device. The method may be performed by a UE or wireless device (e.g. the UE 11 12 or UE 1200 as described later with reference to Figs. 11 and 12 respectively). The second wireless device may perform the method in response to executing suitably formulated computer readable code. The computer readable code may be embodied or stored on a computer readable medium, such as a memory chip, optical disc, or other storage medium. The computer readable medium may be part of a computer program product.

The method begins at step 702 with the relay wireless device obtaining path information relating to at least one candidate indirect connection path between the network node and the first wireless device via one or more relay wireless devices. Each candidate indirect connection path comprises a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices; and

At step 704 the relay wireless device provides the obtained information to the network node.

UE-triggered solution

The following description and the flow charts in Figs. 8-10 relate to the UE-triggered solution.

From a relay UE standpoint, new behaviours and signalling need to be considered such that the remote UE is provided with link quality/performance information of the links between the remote UE and the network node via the relay UE. As used herein, the link quality/performance information may include or comprise measurements of one or more link quality and/or performance parameters. The goal is that the remote UE achieves the best possible end-to-end multi-hop sidelink quality/performance by connecting to the best candidate relay UE(s). In case there are one or several relay UEs between the remote UE and the network node, these relay UEs share their Uu or PC5 (as applicable) link information with the next relay UE such that the candidate/serving relay UE can provide the remote UE with information about the end-to-end performance of the given multi-hop sidelink link.

From a remote UE standpoint, new behaviours and signalling need to be considered such that the remote UE selects the best candidate relay UE when establishing a sidelink link or switching a sidelink link. For that, the remote UE must receive and/or decode the information related to the end-to-end quality/performance of the given sidelink link and make a decision about which one to select. In some embodiments the decision can result from applying or determining a quality/performance metric from the received information.

From a network node standpoint, new behaviour and signalling needs to be considered such that the network informs the remote UE and/or relay UE if these UEs should provide end-to-end or per-link measurements.

The end-to-end path perspective is achieved by combining current and/or predicted per-link quality/performance information of: 1) the direct communication link (e.g. the Uu link) between the network node (e.g. gNB) and the first (if more than one) relay UE, 2) all the direct communication links (e.g. the PC5 links) between relay UEs (if there is more than one relay UE in the indirect connection path) and a candidate relay UE, and 3) the direct communication link (e.g. PC5 link) between the candidate relay UE and the remote UE.

Per-link information can be expressed in terms of one or more quality or performance indicators, e.g., an RSRP value, an RSRQ value, a signal to noise ratio (SNR) value, an SINR, a latency value, a capacity value (e.g. that captures or relates to both SNR and bandwidth), a congestion value, an energy status value, etc. A quality or performance metric can be determined for the full end-to-end path by combining the per-link information for the direct communication links in the indirect connection path. The quality/performance metrics can be based on any of, e.g., a minimum value, a maximum value, a mean value, a weighted average value, a harmonic mean value, etc. of the per-link information. The quality or performance metric for the full end-to-end path can be determined by any node that has the required information available for the links in the end-to-end path. In some embodiments the remote UE determines the quality or performance metric for the full end-to-end path. In other embodiments one of the relay UEs may determine the quality or performance metric for the full end-to-end path and then send this to the remote UE. In other embodiments the network node determines the quality or performance metric for the full end-to-end path and sends this to the remote UE, either directly if a Uu communication link is established between the network node and the remote UE, or via one or more relay UEs.

The relay UE may share the above-mentioned information (the per-link information or the full path information) with the remote UE using either a set of per-link quality/performance indicators or a metric capturing the performance of the multi-hop sidelink link from network to the candidate relay UE.

For example, in the scenario depicted in Fig. 4, in the case of candidate relay UE2, candidate relay UE2 is connected to the core network via a PC5 link between candidate relay UE2 and candidate relay UE1, and a Uu link between candidate relay UE1 and the AN/network node. Hence, candidate relay UE2 can share information (e.g. measurements) related to the quality/performance of these two links with the remote UE. On the other hand, in the case of the alternative indirect communication path via candidate relay UE 3, candidate relay UE3 is connected to the core network via a Uu link between candidate relay 3 and AN. Hence, candidate relay UE3 can share information related to the quality/performance of this Uu link with the remote UE. In the case of both candidate relay UE2 and candidate relay UE3, the information can be shared in their respective discovery messages which shall be received by the remote UE when performing the sidelink discovery procedure.

The following sets out a variety of exemplary embodiments of the techniques described herein.

In an embodiment, new signalling from relay UE(s) is provided for assisting a remote UE in selecting and connecting to a candidate relay UE. The signalling can include information related to the end-to-end performance/quality of a multi-hop sidelink relay link, or information related to the performance/quality of the individual direct communication links in the end-to-end path.

In some embodiments, the information may be transmitted to the remote UE, either by a network node (if the remote UE is in coverage), or by a relay UE. The relay UE can be used to transmit this information regardless of whether the remote UE is in coverage of the network node or out-of-coverage.

In embodiments where the information is transmitted by the relay UE, the information may either have been defined, measured or obtained by the relay UE itself, or may have been defined, measured or obtained by the network node, sent to the relay UE, and then retransmitted by the relay UE to the remote UE.

Following the above embodiments, the information may also be transmitted between relay UEs in the event that there is at least one other relay UE between the candidate relay UE and the network node. In an embodiment, the relay UE may decide itself to indicate to the remote UE on whether end-to-end measurements or per-link measurements should be collected, and then report the decision on which measurements to perform to the network or to the remote UE, so that the recipient of the measurements is aware of what the measurements represent.

In a sub-embodiment, if the relay UE decides by itself that end-to-end measurements should be performed and then reported to the network or remote UE, the relay UE sends a signalling to the network also to inform about this decision.

In embodiments where the information is transmitted by the network node directly to the remote UE (e.g. via a Uu connection between the network node and the remote UE), it may be transmitted in messages such as system information (SI) messages, e.g. in a SI block (SIB), or a Master Information Block (MIB).

In other embodiments where the information is transmitted by the network node directly to the remote UE, the information may be transmitted by the network node using RRC signalling. Another alternative for transmitting the information directly from the network node is to transmit the information using a MAC CE. Yet another alternative for transmitting the information directly from the network node is to transmit the information using a control PDU of the adaptation layer (only in case of sidelink relay). Yet another alternative for transmitting the information directly from the network node is to transmit the information using PHY (physical) layer signalling (e.g., DCI).

In embodiments where the information is transmitted by the network node to the remote UE via one or more relay UEs, the network node may transmit this information to the relay UE in messages such as SI messages, e.g. in a SIB or MIB.

In other embodiments where the information is transmitted by the network node to the remote UE via one or more relay UEs, the information may be transmitted to the relay UE by the network node using any of: RRC signalling, a MAC CE, a control PDU of the adaptation layer (only in case of sidelink relay), and PHY (physical) layer signalling (e.g., DCI).

In embodiments where the information is transmitted by the network node to the remote UE via multiple relay UEs, the relay UEs can exchange this information with each other (until reaching the relay UE that will connect to the remote UE) using SI messages, e.g. one or more SIBs.

In some embodiments, the information related to the end-to-end performance/quality of a multi-hop sidelink relay link, or information related to the performance/quality of the individual direct communication links in the end- to-end path, can involve or comprise at least one value of the following parameters: c. RSRP, RSRQ, SNR and/or SINR value(s) indicating the quality of the wireless backhaul links (e.g. the Uu communication links) that are used for connecting the candidate relay node to the core network. d. A latency indicator, e.g., a quantized value of latency, a congestion indicator. e. A capacity indicator (e.g. capturing or relating to SNR and bandwidth). f. A priority indicator, to indicate the priority level of the associated end-to-end multi-hop sidelink path, e.g., whether the traffic over this end-to-end multi-hop sidelink path will be treated with higher priority compared to other paths. g. An energy status indicator, to indicate the current energy conditions of the relay UEs involved in this end-to-end multi-hop sidelink path. For instance, if one of the relay UEs involved in the end-to-end path is about to run out of power (e.g., it has a low battery), a flag can be sent to the remote UE so that it will not select this path in case it has large traffic demands or critical data to be sent.

In some embodiments, any of the above parameter values comprised in the information transmitted to the remote UE can be any of a minimum value of the parameter for the link or end-to-end path, a maximum value of the parameter for the link or end-to-end path, a mean value of the parameter for the link or end-to-end path, a weighted average value of the parameter for the link or end-to-end path, and a harmonic mean value of the parameter for the link or end-to-end path.

In some embodiments, if any of the above parameter values relate to individual direct communication links, the remote UE may perform a calculation or derivation using the received parameter values to decide which candidate relay UE to connect to. The calculation or derivation can comprise determining any of a minimum value, a maximum value, a mean value, a weighted average value, and a harmonic mean value.

In some embodiments, the node transmitting the information to the remote UE, i.e., the network node or the relay UE, may specifically instruct the remote UE about: a. which of the above types of parameter should be used, i.e., RSRP, latency, energy status, etc.; b. which metric of the ones set out above should be used, i.e., a minimum value, a mean value, etc.; c. which scale of the ones set out above should be used, i.e., linear or logarithmic.

In some embodiments, if the remote UE has not received a specific instruction regarding the above procedures (i.e. which type of parameter, which metric, which scale, etc.), the remote UE proceeds according to a default behaviour.

In various embodiments, the remote UE reads/decodes received multi-hop sidelink-related information and uses this information, together with information received in sidelink discovery messages as part of a sidelink discovery procedure to perform relay UE selection (or relay UE reselection if the remote UE already has an established indirect connection path with the network node). In particular, the remote UE can perform relay UE (reflection by considering the quality or performance of the end-to-end multi-hop sidelink path. In some embodiments, the multi-hop sidelink quality or performance metric that the remote UE uses to combine individual direct communication link information can be any of a minimum value, a maximum value, a mean value, a weighted average value, and a harmonic mean value. In some embodiments, the multi-hop sidelink quality or performance metric calculated by the remote UE can comprise one or more linear values or (if applicable) one or more logarithmic values.

In some embodiments, the remote UE performs an initial relay selection based on the PC5 link of the discovery message to find a suitable relay to connect to, and then performs a relay UE reselection that considers all the links between the remote UE and the network nodes, i.e., the Uu link and all the PC5 links. Thus, In these embodiments the remote UE performs the initial relay selection in a conventional manner, and then uses the techniques described herein to select a better relay UE/connection path to use.

In alternative embodiments, the remote UE performs relay selection by first evaluating the suitability of the PC5 link of each direct communication link from the remote UE to candidate relay UEs, e.g., by applying sidelink- related criteria. Then, for a relay UE with a suitable PC5 link, the remote UE can further evaluate the suitability of the end-to-end multi-hop path including both the PC5 and Uu links (i.e. the Uu link from the 'suitable' relay UE to the network node). In the end, the remote UE connects to the first candidate relay UE that provides an end-to-end path that meets an end-to-end path suitability requirement.

In another embodiment, the remote UE performs relay reselection by first evaluating the suitability of the PC5 link with each relay UE, e.g., by applying a sidelink-related criteria. For the candidate relay UE(s) with suitable PC5 links, the remote UE further ranks or orders them based on multi-hop sidelink path quality or performance determined using information of the PC5 link(s) and Uu link. In the end, the remote UE selects (and connects to) the candidate relay UE with the highest rank (or order) value.

In some embodiments, the criterion/threshold mentioned above that is to be satisfied in order for a remote UE to connect to a candidate relay UE can relate to the end-to-end path, or relate only to the PC5 link between the candidate relay UE and the remote UE, where applicable. In some embodiments, the selection criterion/threshold can be signalled to the remote UE by either the network node or the candidate relay UE(s). In some embodiments, if the remote UE has not been specifically instructed by either the network node or the candidate relay UE about the selection criterion/threshold, the remote UE may use a preconfigured or a stored value.

In some embodiments, the remote UE and/or candidate relay UEs may be configured by the (or another) relay UE or by the network node with one or multiple measurement configurations. The measurement configurations may comprise any of: a. at least one measurement configuration that provides the relay UE or remote UE with a configuration regarding how to measure direct communication links and/or indirect connection paths in terms of at least one multi-hop/E2E metric; b. at least one measurement configuration that provides the relay UE or remote UE with a configuration regarding how to measure direct communication links and/or indirect connection paths in terms of one or multiple per-hop (per-link) metrics, and to derive multi-hop measurements based on per-hop measurements. In some embodiments, on reception of one or multiple measurement configurations, the relay UE and/or remote UE performs measurements of links and/or paths, including serving paths and non-serving paths. The measurements can be in terms of at least one of the following metrics: one or multiple multi-hop/E2E metrics, and one or multiple per-hop metrics (from which multi-hop/E2E measurements are derived from the per-hop measurements).

In some embodiments, the relay UE and/or remote UE can perform measurements periodically, in response to an event (i.e. event triggered), or on reception of a request message from the gNB or from another UE.

As noted above, Fig. 4 depicts an example scenario featuring several SL U2N relays. The following section describes how a remote UE can select a candidate relay UE to connect to according to the techniques described herein.

The remote UE in Fig. 4 is not within the coverage area of the network node (AN). If the remote UE was in the coverage area of AN, the following examples could also or alternatively be entirely managed by AN. That is, the information about all the candidate relay UEs and their corresponding E2E quality/performance indicators could be transmitted by the AN directly to the remote UE. The following examples are based on the remote UE being out- of-network-coverage.

In the case of candidate relay UE2, relay UE2 transmits information about the multi-hop sidelink link from relay UE2 to AN, i.e. information related to relay UE2's PC5 link to relay UE1, and relay UETs Uu link to AN. The information can be sent to the remote UE either per-link or in the form of a composite value, e.g., a mean of the perlink values. The information can be expressed in terms of, e.g., RSRP values, latency values, or other quality/performance metrics. The information can also be expressed either in linear or logarithmic scales. The remote UE may then use the information in relay UE2's discovery message to derive or obtain the end-to-end value for the indirect connection path via relay UE2 and relay UE1, for example for comparison to information for other candidate relay UEs or indirect connection paths and, in some embodiments, to compare against a threshold or criterion.

In the case of candidate relay UE3, relay UE3 transmits information about the link from relay UE3 to AN, i.e., information related to its Uu link to AN, and the way in which this is done, and the form that this information takes, are similar to the ones explained above for candidate relay UE2. The remote UE may then use the information in relay UE3's discovery message to derive or obtain the end-to-end value for the indirect connection path via relay UE3, for example for comparison to information for other candidate relay UEs or indirect connection paths and, in some embodiments, to compare against a threshold or criterion. In the event that the remote UE does not receive specific instructions of which metric, indicator, or scale to use from relay UE2 or from relay UE3, it may proceed using preconfigured or default behaviours.

Once the remote UE has obtained end-to-end performance/quality metrics from relay UE2 and relay UE3, the remote UE selects the one among them offering the better predicted or expected performance. Once it has selected one of the candidate relay UEs, the remote UE compares the candidate relay UE performance/quality metric with an end-to-end path performance criterion or threshold to ultimately decide whether it may connect to the selected candidate relay UE or not.

In an embodiment, among multiple possible indirect connection paths, the remote UE selects an indirect connection path comprising one or multiple relay UEs which gives the strongest or best end-to-end performance/quality in terms of one or multiple metrics as described in any of the above embodiments.

In an embodiment, among multiple possible connection paths comprising at least one indirect connection path and a direct connection path to the network, the remote UE selects the path which gives the best or strongest performance/quality in terms of one or multiple metrics as described in any of the above embodiments. In the event that a direct connection path is compared to an indirect connection path, the remote UE may compare the performance/quality of the one hop in the direct path to the end-to-end performance/quality of the indirect connection path.

The remote UE may perform the above procedures in a variety of mobility scenarios. For example, a remote UE can perform the above as described in any one of the above embodiments when the remote UE initiates a RRC connection setup procedure towards a gNB via a selected path. Another or alternative scenario in which these techniques can be used is where the remote UE initiates a RRC connection reestablishment procedure towards a gNB via a selected path. Another or alternative scenario in which these techniques can be used is where the remote UE initiates a mobility procedure when in RRC I NACTIVE, e.g., RRC Resume. Another or alternative scenario in which these techniques can be used is where the remote UE initiates relay UE selection and reselection in or out of network coverage.

Fig. 8 is a flow chart illustrating a method according to various embodiments performed by a first wireless device/remote UE. The method is for selecting one or more relay wireless devices to provide an indirect connection path between a network node and the first wireless device via the selected one or more relay wireless devices. The method may be performed by a UE or wireless device (e.g. the UE 1112 or UE 1200 as described later with reference to Figs. 11 and 12 respectively). The first wireless device may perform the method in response to executing suitably formulated computer readable code. The computer readable code may be embodied or stored on a computer readable medium, such as a memory chip, optical disc, or other storage medium. The computer readable medium may be part of a computer program product.

The method begins at step 802 with the first wireless device obtaining information relating to a plurality of direct communication links between any of: the network node, the first wireless device and one or more candidate relay wireless devices. The plurality of direct communication links provide at least one candidate indirect connection path between the network node and the first wireless device.

In step 804 the first wireless device selects at least one of the one or more candidate relay wireless devices to provide the indirect connection path between the network node and the first wireless device. The selection is based on path information relating to the at least one candidate indirect connection paths that is determined from the obtained information.

Fig. 9 is a flow chart illustrating a method according to various embodiments performed by a second wireless device/relay UE. The first relay wireless device is configurable to operate as a relay wireless device in an indirect connection path between a network node and a first wireless device. The method may be performed by a UE or wireless device (e.g. the UE 1112 or UE 1200 as described later with reference to Figs. 11 and 12 respectively). The second wireless device may perform the method in response to executing suitably formulated computer readable code. The computer readable code may be embodied or stored on a computer readable medium, such as a memory chip, optical disc, or other storage medium. The computer readable medium may be part of a computer program product.

The method begins at step 902 in which the second wireless device obtains path information relating to at least one candidate indirect connection path between the first wireless device and the network node via one or more relay wireless devices. Each candidate indirect connection path comprises a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices.

In step 904 the second wireless device provides the obtained information to the first wireless device.

Fig. 10 is a flow chart illustrating a method according to various embodiments performed by a network node/base station/eNB/gNB. The network node network node is configurable to communicate with a first wireless device via an indirect connection path via one or more relay devices. The method may be performed by a network node (e.g. the network node 11 10 or network node 1300 as described later with reference to Fig. 11 and 13 respectively). The network node may perform the method in response to executing suitably formulated computer readable code. The computer readable code may be embodied or stored on a computer readable medium, such as a memory chip, optical disc, or other storage medium. The computer readable medium may be part of a computer program product.

The method begins at step 1002 with the network node obtaining path information relating to at least one candidate indirect connection path between the network node and the first wireless device via one or more candidate relay wireless devices. Each candidate indirect connection path comprises a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices

In step 1004 the network node provides the obtained information to the first wireless device.

Fig. 11 shows an example of a communication system 1100 in accordance with some embodiments.

In the example, the communication system 1100 includes a telecommunication network 1102 that includes an access network 1104, such as a radio access network (RAN), and a core network 1106, which includes one or more core network nodes 1108. The access network 1104 includes one or more access network nodes, such as access network nodes 1110a and 1110b (one or more of which may be generally referred to as access network nodes 1110), or any other similar 3^rd Generation Partnership Project (3GPP) access node or non-3GPP access point. The access network nodes 1110 facilitate direct or indirect connection of wireless devices (also referred to interchangeably herein as user equipment (UE)), such as by connecting UEs 1112a, 1112b, 1112c, and 1112d (one or more of which may be generally referred to as UEs 1112) to the core network 1106 over one or more wireless connections. The access network nodes 1110 may be, for example, access points (APs) (e.g. radio access points), base stations (BSs) (e.g. radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)).

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 1100 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 1100 may include and/or interface with any type of communication, telecommunication, data, cellular, radio network, and/or other similar type of system.

The wireless devices/UEs 1112 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 1110 and other communication devices. Similarly, the access network nodes 1110 are arranged, capable, configured, and/or operable to communicate directly or indirectly with the UEs 1112 and/or with other network nodes or equipment in the telecommunication network 1102 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 1102.

In the depicted example, the core network 1106 connects the access network nodes 1110 to one or more hosts, such as host 1116. 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 1106 includes one more core network nodes (e.g. core network node 1108) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the wireless devices/UEs, access network nodes, and/or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 1108. 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 1116 may be under the ownership or control of a service provider other than an operator or provider of the access network 1104 and/or the telecommunication network 1102, and may be operated by the service provider or on behalf of the service provider. The host 1116 may host a variety of applications to provide one or more services. Examples of such applications include the provision of live and/or pre-recorded audio/video content, data collection services, for example, 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 1100 of Fig. 11 enables connectivity between the wireless devices/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 1102 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 1102 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 1102. For example, the telecommunications network 1102 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)ZMassive Internet of Things (loT) services to yet further UEs.

In some examples, the UEs 1112 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 1104 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 1104. Additionally, a UE may be configured for operating in single- or multi-RAT or multi-standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC).

In the example illustrated in Fig. 11 , the hub 1114 communicates with the access network 1104 to facilitate indirect communication between one or more UEs (e.g. UE 1112c and/or 1112d) and access network nodes (e.g. access network node 1110b). In some examples, the hub 1114 may be a controller, router, a content source and analytics node, or any of the other communication devices described herein regarding UEs. For example, the hub 11 14 may be a broadband router enabling access to the core network 1106 for the UEs. As another example, the hub 11 14 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 1110, or by executable code, script, process, or other instructions in the hub 11 14. As another example, the hub 1114 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 1114 may be a content source. For example, for a UE that is a Virtual Reality (VR) headset, display, loudspeaker or other media delivery device, the hub 1114 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 1114 then provides to the UE either directly, after performing local processing, and/or after adding additional local content. In still another example, the hub 1114 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 1114 may have a constant/persistent or intermittent connection to the network node 1110b. The hub 11 14 may also allow for a different communication scheme and/or schedule between the hub 1114 and UEs (e.g. UE 11 12c and/or 1112d), and between the hub 1114 and the core network 1106. In other examples, the hub 1114 is connected to the core network 1106 and/or one or more UEs via a wired connection. Moreover, the hub 1114 may be configured to connect to a machine-to-machine (M2M) service provider over the access network 1104 and/or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 11 10 while still connected via the hub 1114 via a wired or wireless connection. In some embodiments, the hub 1114 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 1110b. In other embodiments, the hub 1114 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 1110b, but which is additionally capable of operating as a communication start and/or end point for certain data channels.

Fig. 12 shows a wireless device or UE 1200 in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged and/or operable to communicate wirelessly with network nodes and/or other UEs. Examples of a wireless device/UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless camera, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehicle-mounted or vehicle embedded/integrated wireless device, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3GPP), including a narrow band internet of things (NB-loT) UE, a machine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE.

A wireless device/UE may support device-to-device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle-to-everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and/or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g. a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g. a smart power meter). The UE 1200 includes processing circuitry 1202 that is operatively coupled via a bus 1204 to an input/output interface 1206, a power source 1208, a memory 1210, a communication interface 1212, and/or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Fig. 12. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

The processing circuitry 1202 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 1210. The processing circuitry 1202 may be implemented as one or more hardware- implemented state machines (e.g. in discrete logic, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general-purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 1202 may include multiple central processing units (CPUs). The processing circuitry 1202 may be operable to provide, either alone or in conjunction with other UE 1200 components, such as the memory 1210, to provide UE 1200 functionality. For example, the processing circuitry 1202 may be configured to cause the UE 1202 to perform the methods as described with reference to Figs. 5 and/or 6.

In the example, the input/output interface 1206 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and/or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE 1200. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g. a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device.

In some embodiments, the power source 1208 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g. an electricity outlet), photovoltaic device, or power cell, may be used. The power source 1208 may further include power circuitry for delivering power from the power source 1208 itself, and/or an external power source, to the various parts of the UE 1200 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 1208. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 1208 to make the power suitable for the respective components of the UE 1200 to which power is supplied. The memory 1210 may be or be configured to include memory such as random access memory (RAM), readonly memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 1210 includes one or more application programs 1214, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 1216. The memory 1210 may store, for use by the UE 1200, any of a variety of various operating systems or combinations of operating systems.

The memory 1210 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a Universal SIM (USIM) and/or Integrated SIM (ISIM), other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUlCC), integrated UICC (IUICC) or a removable UICC commonly known as ‘SIM card.' The memory 1210 may allow the UE 1200 to access instructions, application programs and the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied as or in the memory 1210, which may be or comprise a device-readable storage medium.

The processing circuitry 1202 may be configured to communicate with an access network or other network using the communication interface 1212. The communication interface 1212 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 1222. The communication interface 1212 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g. another UE or a network node in an access network). Each transceiver may include a transmitter 1218 and/or a receiver 1220 appropriate to provide network communications (e.g. optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 1218 and receiver 1220 may be coupled to one or more antennas (e.g. antenna 1222) and may share circuit components, software or firmware, or alternatively be implemented separately.

In some embodiments, communication functions of the communication interface 1212 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented in according to one or more communication protocols and/or standards, such as IEEE 802.11 , Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol/internet protocol (TCP/IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), Quick UDP Internet Connection (QUIC), Hypertext Transfer Protocol (HTTP), and so forth.

Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 1212, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g. once every 15 minutes if it reports the sensed temperature), random (e.g. to even out the load from reporting from several sensors), in response to a triggering event (e.g. when moisture is detected an alert is sent), in response to a request (e.g. a user initiated request), or a continuous stream (e.g. a live video feed of a patient).

As another example, a UE comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or controls a robotic arm performing a medical procedure according to the received input.

A UE, when in the form of an Internet of Things (loT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application and healthcare. Non-limiting examples of such an loT device are devices which are or which are embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door/window sensor, a flood/moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or Virtual Reality (VR), a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an loT device comprises circuitry and/or software in dependence on the intended application of the loT device in addition to other components as described in relation to the UE 1200 shown in Fig. 12.

As yet another specific example, in an loT scenario, a UE may represent a machine or other device that performs monitoring and/or measurements, and transmits the results of such monitoring and/or measurements to another UE and/or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-loT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation.

In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone's speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g. by controlling an actuator) to increase or decrease the drone's speed. The first and/or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators.

Fig. 13 shows a network node 1300 in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged and/or operable to communicate directly or indirectly with a UE and/or with other network nodes or equipment, in a telecommunication network. Examples of network nodes include, but are not limited to, access network nodes such as access points (APs) (e.g. radio access points), base stations (BSs) (e.g. radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)).

Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units and/or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).

Other examples of network nodes include multiple transmission point (multi-TRP) 5G access nodes, multistandard radio (MSR) equipment such as MSR base stations (BSs), network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi-cell/multicast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g. Evolved Serving Mobile Location Centers (E-SMLCs)), and/or Minimization of Drive Tests (MDTs).

The network node 1300 includes processing circuitry 1302, a memory 1304, a communication interface 1306, and a power source 1308, and/or any other component, or any combination thereof. The network node 1300 may be composed of multiple physically separate components (e.g. a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node 1300 comprises multiple separate components (e.g. BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network node 1300 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g. separate memory 1304 for different RATs) and some components may be reused (e.g. a same antenna 1310 may be shared by different RATs). The network node 1300 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 1300, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 1300.

The processing circuitry 1302 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other network node 1300 components, such as the memory 1304, to provide network node 1300 functionality. For example, the processing circuitry 1302 may be configured to cause the network node to perform the methods as described with reference to Fig. 7.

In some embodiments, the processing circuitry 1302 includes a system on a chip (SOC). In some embodiments, the processing circuitry 1302 includes one or more of radio frequency (RF) transceiver circuitry 1312 and baseband processing circuitry 1314. In some embodiments, the radio frequency (RF) transceiver circuitry 1312 and the baseband processing circuitry 1314 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 1312 and baseband processing circuitry 1314 may be on the same chip or set of chips, boards, or units.

The memory 1304 may comprise any form of volatile or non-volatile computer-readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device-readable and/or computer-executable memory devices that store information, data, and/or instructions that may be used by the processing circuitry 1302. The memory 1304 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and/or other instructions capable of being executed by the processing circuitry 1302 and utilized by the network node 1300. The memory 1304 may be used to store any calculations made by the processing circuitry 1302 and/or any data received via the communication interface 1306. In some embodiments, the processing circuitry 1302 and memory 1304 is integrated.

The communication interface 1306 is used in wired or wireless communication of signalling and/or data between network nodes, the access network, the core network, and/or a UE. As illustrated, the communication interface 1306 comprises port(s)/terminal(s) 1316 to send and receive data, for example to and from a network over a wired connection.

In embodiments, the communication interface 1306 also includes radio front-end circuitry 1318 that may be coupled to, or in certain embodiments a part of, the antenna 1310. Radio front-end circuitry 1318 comprises filters 1320 and amplifiers 1322. The radio front-end circuitry 1318 may be connected to an antenna 1310 and processing circuitry 1302. The radio front-end circuitry may be configured to condition signals communicated between antenna 1310 and processing circuitry 1302. The radio front-end circuitry 1318 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 1318 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 1320 and/or amplifiers 1322. The radio signal may then be transmitted via the antenna 1310. Similarly, when receiving data, the antenna 1310 may collect radio signals which are then converted into digital data by the radio front-end circuitry 1318. The digital data may be passed to the processing circuitry 1302. In other embodiments, the communication interface may comprise different components and/or different combinations of components.

In certain alternative embodiments, the access network node 1300 does not include separate radio front-end circuitry 1318, instead, the processing circuitry 1302 includes radio front-end circuitry and is connected to the antenna 1310. Similarly, in some embodiments, all or some of the RF transceiver circuitry 1312 is part of the communication interface 1306. In still other embodiments, the communication interface 1306 includes one or more ports or terminals 1316, the radio front-end circuitry 1318, and the RF transceiver circuitry 1312, as part of a radio unit (not shown), and the communication interface 1306 communicates with the baseband processing circuitry 1314, which is part of a digital unit (not shown).

The antenna 1310 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. The antenna 1310 may be coupled to the radio front-end circuitry 1318 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In certain embodiments, the antenna 1310 is separate from the network node 1300 and connectable to the network node 1300 through an interface or port.

The antenna 1310, communication interface 1306, and/or the processing circuitry 1302 may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by the network node. Any information, data and/or signals may be received from a UE, another network node and/or any other network equipment. Similarly, the antenna 1310, the communication interface 1306, and/or the processing circuitry 1302 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and/or signals may be transmitted to a UE, another network node and/or any other network equipment.

The power source 1308 provides power to the various components of network node 1300 in a form suitable for the respective components (e.g. at a voltage and current level needed for each respective component). The power source 1308 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 1300 with power for performing the functionality described herein. For example, the network node 1300 may be connectable to an external power source (e.g. the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 1308. As a further example, the power source 1308 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.

Embodiments of the network node 1300 may include additional components beyond those shown in Fig. 13 for providing certain aspects of the network node's functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein. For example, the network node 1300 may include user interface equipment to allow input of information into the network node 1300 and to allow output of information from the network node 1300. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 1300.

Fig. 14 is a block diagram illustrating a virtualization environment 1400 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines (VMs) implemented in one or more virtual environments 1400 hosted by one or more of hardware nodes, such as a hardware computing device that operates as an access network node, a wireless device/UE, or a core network node. Further, in embodiments in which the virtual node does not require radio connectivity (e.g. a core network node), then the node may be entirely virtualized.

Applications 1402 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment 1400 to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein.

Hardware 1404 includes processing circuitry, memory that stores software and/or instructions executable by hardware processing circuitry, and/or other hardware devices as described herein, such as a network interface, input/output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers 1406 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 1408a and 1408b (one or more of which may be generally referred to as VMs 1408), and/or perform any of the functions, features and/or benefits described in relation with some embodiments described herein. The virtualization layer 1406 may present a virtual operating platform that appears like networking hardware to the VMs 1408.

The VMs 1408 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 1406. Different embodiments of the instance of a virtual appliance 1402 may be implemented on one or more of VMs 1408, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment.

In the context of NFV, a VM 1408 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs 1408, and that part of hardware 1404 that executes that VM, be it hardware dedicated to that VM and/or hardware shared by that VM with others of the VMs, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more VMs 1408 on top of the hardware 1404 and corresponds to the application 1402. Hardware 1404 may be implemented in a standalone network node with generic or specific components. Hardware 1404 may implement some functions via virtualization. Alternatively, hardware 1404 may be part of a larger cluster of hardware (e.g. such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 1410, which, among others, oversees lifecycle management of applications 1402. In some embodiments, hardware 1404 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station. In some embodiments, some signalling can be provided with the use of a control system 1412 which may alternatively be used for communication between hardware nodes and radio units.

Fig. 15 shows a communication diagram of a host 1502 communicating via a network node 1504 with a UE 1506 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as a UE 1112a of Fig. 11 and/or UE 1200 of Fig. 12), network node (such as network node 1110a of Fig. 11 and/or network node 1300 of Fig. 13), and host (such as host 1116 of Fig. 11 ) discussed in the preceding paragraphs will now be described with reference to Fig. 15.

Embodiments of host 1502 include hardware, such as a communication interface, processing circuitry, and memory. The host 1502 also includes software, which is stored in or accessible by the host 1502 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 1506 connecting via an over-the-top (OTT) connection 1550 extending between the UE 1506 and host 1502. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 1550.

The network node 1504 includes hardware enabling it to communicate with the host 1502 and UE 1506. The connection 1560 may be direct or pass through a core network (like core network 1106 of Fig. 11) 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 1506 includes hardware and software, which is stored in or accessible by UE 1506 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 1506 with the support of the host 1502. In the host 1502, an executing host application may communicate with the executing client application via the OTT connection 1550 terminating at the UE 1506 and host 1502. 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 1550 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 1550. The OTT connection 1550 may extend via a connection 1560 between the host 1502 and the network node 1504 and via a wireless connection 1570 between the network node 1504 and the UE 1506 to provide the connection between the host 1502 and the UE 1506. The connection 1560 and wireless connection 1570, over which the OTT connection 1550 may be provided, have been drawn abstractly to illustrate the communication between the host 1502 and the UE 1506 via the network node 1504, without explicit reference to any intermediary devices and the precise routing of messages via these devices.

As an example of transmitting data via the OTT connection 1550, in step 1508, the host 1502 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 1506. In other embodiments, the user data is associated with a UE 1506 that shares data with the host 1502 without explicit human interaction. In step 1510, the host 1502 initiates a transmission carrying the user data towards the UE 1506. The host 1502 may initiate the transmission responsive to a request transmitted by the UE 1506. The request may be caused by human interaction with the UE 1506 or by operation of the client application executing on the UE 1506. The transmission may pass via the network node 1504, in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 1512, the network node 1504 transmits to the UE 1506 the user data that was carried in the transmission that the host 1502 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 1514, the UE 1506 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 1506 associated with the host application executed by the host 1502.

In some examples, the UE 1506 executes a client application which provides user data to the host 1502. The user data may be provided in reaction or response to the data received from the host 1502. Accordingly, in step 1516, the UE 1506 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 1506. Regardless of the specific manner in which the user data was provided, the UE 1506 initiates, in step 1518, transmission of the user data towards the host 1502 via the network node 1504. In step 1520, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 1504 receives user data from the UE 1506 and initiates transmission of the received user data towards the host 1502. In step 1522, the host 1502 receives the user data carried in the transmission initiated by the UE 1506.

One or more of the various embodiments improve the performance of OTT services provided to the UE 1506 using the OTT connection 1550, in which the wireless connection 1570 forms the last segment. More precisely, the teachings of these embodiments may provide an indirect connection path that has improved data rate, latency, and/or reliability, and thereby provide benefits such as reduced user waiting time, improved content resolution or smoother presentation, and better responsiveness.

In an example scenario, factory status information may be collected and analysed by the host 1502. As another example, the host 1502 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 1502 may collect and analyse real-time data to assist in controlling vehicle congestion (e.g. controlling traffic lights). As another example, the host 1502 may store surveillance video uploaded by a UE. As another example, the host 1502 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 1502 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, analysing 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 1550 between the host 1502 and UE 1506, 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 1502 and/or UE 1506. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 1550 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 1550 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not directly alter the operation of the network node 1504. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signalling that facilitates measurements of throughput, propagation times, latency and the like, by the host 1502. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or 'dummy' messages, using the OTT connection 1550 while monitoring propagation times, errors, etc.

Although the computing devices described herein (e.g. UEs, network nodes, etc.) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and/or software needed to perform the tasks, features, functions and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and/or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware.

In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer-readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole, and/or by end users and a wireless network generally.

The foregoing merely illustrates the principles of the disclosure. Various modifications and alterations to the described embodiments will be apparent to those skilled in the art in view of the teachings herein. It will thus be appreciated that those skilled in the art will be able to devise numerous systems, arrangements, and procedures that, although not explicitly shown or described herein, embody the principles of the disclosure and can be thus within the scope of the disclosure. Various exemplary embodiments can be used together with one another, as well as interchangeably therewith, as should be understood by those having ordinary skill in the art.

EMBODIMENTS

Network-triggered solutions

The following Group A Embodiments and Group B Embodiments relate to the network-triggered solutions.

Group B Embodiments

1. A method performed in a network node for selecting at least one relay wireless device to provide an indirect connection path between the network node and a first wireless device via the at least one selected relay wireless device, the method comprising: obtaining information relating to a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices, wherein the plurality of direct communication links provide at least one candidate indirect connection path between the network node and the first wireless device; selecting at least one of the one or more candidate relay wireless devices to provide the indirect connection path between the network node and the first wireless device, wherein the selection is based on path information relating to the at least one candidate indirect connection paths that is determined from the obtained information; and providing an indication of the at least one selected relay wireless device to the first wireless device.

2. The method according to embodiment 1 , wherein the obtained information relates to guality and/or performance of the direct communication links or the candidate indirect connection paths.

3. The method according to embodiments 1 or 2, wherein obtaining the information comprises: receiving the information from one or more wireless devices.

4. The method according to embodiment 3, wherein the one or more wireless devices comprises the first wireless device and/or one or more candidate relay wireless devices.

5. The method according to embodiments 1-4, wherein the obtained information comprises at least one guality and/or performance measurement for each of the plurality of direct communication links.

6. The method according to embodiment 1 -5, wherein obtaining the information comprises: performing measurements of a direct communication link between the network node and any of: the first wireless device and one or more candidate relay wireless devices.

7. The method according to any of embodiments 1-6, wherein the obtained information comprises values for one or more of the following parameters: a Reference Signal Received Power, RSRP, a Reference Signal Received Quality, RSRQ, a Signal to Noise Ratio, SNR, a Signal to Interference Noise Ratio, SINR, a latency indicator, a congestion indicator, a capacity indicator, a priority indicator for an associated indirect communication path, and an energy status indicator, wherein each parameter relates to one of the plurality of direct communication links.

8. The method according to any of embodiments 1 -4, wherein the obtained information comprises path information for each of the at least one candidate indirect connection paths.

9. The method according to embodiment 8, wherein the path information comprises a measure of the end-to-end quality and/or performance for each of the at least one candidate indirect connection paths.

10. The method according to any of embodiments 8 or 9, wherein the path information comprises values for one or more of the following parameters: a Reference Signal Received Power, RSRP, a Reference Signal Received Quality, RSRQ, a Signal to Noise Ratio, SNR, a Signal to Interference Noise Ratio, SINR, a latency indicator, a congestion indicator, a capacity indicator, a priority indicator for an associated indirect communication path, and an energy status indicator, wherein each of the parameters relates to one of the candidate indirect connection paths.

11 . The method according to embodiments 1 -10, wherein the method further comprises: prior to obtaining the information, sending an information request message to a wireless device.

12. The method according to embodiment 11, wherein the information request message is for configuring the wireless device to: obtain the information; and provide the information to the network node.

13. The method according to embodiments 11 or 12, wherein the recipient wireless device is the first wireless device and/or a candidate relay wireless device.

14. The method according to any of embodiments 11-13, wherein the information request message is sent directly to the recipient wireless devices.

15. The method according to any of embodiments 11-14, wherein the information request message is sent to the recipient wireless devices via one or more relay wireless devices.

16. The method according to any of embodiments 1-15, wherein providing the indication to the first wireless device comprises transmitting the indication directly to the first wireless device. 17. The method according to any of embodiments 1-16, wherein providing the indication to the first wireless device comprises transmitting the indication to the first wireless device via one or more relay wireless devices.

18. The method according to any of embodiments 1-17, wherein the indication is provided via one or more of: a system information message, a System Information Block, SIB, a Master Information Block, MIB, a discovery message, a Radio Resource Control, RRC, message, Medium Access Control, MAC, Control Element, CE, a Protocol Data Unit of the adaptation layer, and a physical, PHY, layer signalling message.

19. The method of any of the previous embodiments, further comprising: providing user data; and forwarding the user data to a host or a user equipment.

Group A Embodiments

20. A method performed by a first wireless device, the method comprising: obtaining path information relating to at least one candidate indirect connection path between a network node and the first wireless device via one or more relay wireless devices, wherein each candidate indirect connection path comprises a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices; and providing the obtained information to the network node.

21. The method according to embodiment 20, wherein the obtained path information relates to quality and/or performance of the direct communication links or the candidate indirect connection paths.

22. The method according to embodiments 20 or 21 , wherein the method further comprises: prior to obtaining the path information, receiving, from the network node, an information request message.

23. The method according to embodiment 22, wherein the information request message is for configuring the first wireless device to: obtain the path information; and provide the path information to the network node.

24. The method according to any of embodiments 20-23, wherein obtaining the path information comprises: performing measurements of one or more direct communication links between the first wireless device and any of: the network node and one or more candidate relay wireless devices; and/or receiving, from one or more wireless devices, information relating to one or more direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices.

25. The method according to embodiment 24, wherein the information relating to one or more direct communication links relates to quality and/or performance.

26. The method according to embodiment 24 or 25, wherein the information relating to one or more direct communication links comprises values for one or more of the following parameters: a Reference Signal Received Power, RSRP, a Reference Signal Received Quality, RSRQ, a Signal to Noise Ratio, SNR, a Signal to Interference Noise Ratio, SINR, a latency indicator, a congestion indicator, a capacity indicator, a priority indicator for an associated indirect communication path, and an energy status indicator, wherein each parameter relates to one of the plurality of direct communication links.

27. The method according to any of embodiments 24-26, wherein obtaining the path information further comprises: determining the path information based on the measurements and/or received information.

28. The method according to any of embodiments 20-27, wherein the path information comprises a measure of the end-to-end quality and/or performance for each of the at least one candidate indirect connection paths.

29. The method according to any of embodiments 20-28, wherein the path information comprises values for one or more of the following parameters: a Reference Signal Received Power, RSRP, a Reference Signal Received Quality, RSRQ, a Signal to Noise Ratio, SNR, a Signal to Interference Noise Ratio, SINR, a latency indicator, a congestion indicator, a capacity indicator, a priority indicator for an associated indirect communication path, and an energy status indicator, wherein each of the parameters relates to one of the candidate indirect connection paths.

30. The method according to any of embodiments 20-29, wherein providing the obtained path information comprises sending the path information directly to the network node.

31. The method according to any of embodiments 20-30, wherein providing the obtained information comprises sending the information to the network node via one or more relay wireless devices.

32. The method according to any of embodiments 20-31, wherein the method further comprises: receiving an indication of at least one relay wireless device selected to provide an indirect connection path between the network node and the first wireless device via the at least one selected relay wireless device. 33. The method according to embodiment 32, wherein the method further comprises: establishing an indirect connection path to the network via the at least one relay wireless device according to the received indication.

34. The method according to embodiment 32 or 33, wherein the indication is received in one or more of: a system information message, a System Information Block, SIB, a Master Information Block, MIB, a Radio Resource Control, RRC, message, Medium Access Control, MAC, Control Element, CE, a Protocol Data Unit of the adaptation layer, and a physical, PHY, layer signalling message, a discovery message, a PC5-RRC message, a control Protocol Data Unit of the adaptation layer, and a Sidelink Control Information, SCI, message.

35. The method according to any of embodiments 32-34, wherein the indication is received directly from the network node.

36. The method according to any of embodiments 32-34, wherein the indication is received from the network node via one or more relay wireless devices.

37. A method performed by a first relay wireless device capable of providing an indirect connection path between a network node and a first wireless device, the method comprising: obtaining path information relating to at least one candidate indirect connection path between the network node and the first wireless device via one or more relay wireless devices, wherein each candidate indirect connection path comprises a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices; and providing the obtained information to the network node.

38. The method according to embodiment 37, wherein the obtained path information relates to quality and/or performance of the direct communication links or the candidate indirect connection paths.

39. The method according to embodiments 37 or 38, wherein the method further comprises: prior to obtaining the path information, receiving, from the network node, an information request message.

40. The method according to embodiment 39, wherein the information request message is for configuring the first relay wireless device to: obtain the path information; and provide the path information to the network node. 41 . The method according to any of embodiments 37-40, wherein obtaining the path information comprises: performing measurements of one or more direct communication links between the first relay wireless device and any of: the network node, the first wireless device, and one or more candidate relay wireless devices; and/or receiving, from one or more wireless devices, information relating to one or more direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices.

42. The method according to embodiment 41, wherein the information relating to one or more direct communication links relates to quality and/or performance.

43. The method according to embodiments 41 or 42, wherein the information relating to one or more direct communication links comprises values for one or more of the following parameters: a Reference Signal Received Power, RSRP, a Reference Signal Received Quality, RSRQ, a Signal to Noise Ratio, SNR, a Signal to Interference Noise Ratio, SI NR, a latency indicator, a congestion indicator, a capacity indicator, a priority indicator for an associated indirect communication path, and an energy status indicator, wherein each parameter relates to one of the plurality of direct communication links.

44. The method according to any of embodiments 41-43, wherein obtaining the path information further comprises: determining the path information based on the measurements and/or received information.

45. The method according to any of embodiments 37-44, wherein the path information comprises a measure of the end-to-end quality and/or performance for each of the at least one candidate indirect connection paths.

46. The method according to any of embodiments 37-45, wherein the path information comprises values for one or more of the following parameters: a Reference Signal Received Power, RSRP, a Reference Signal Received Quality, RSRQ, a Signal to Noise Ratio, SNR, a Signal to Interference Noise Ratio, SI NR, a latency indicator, a congestion indicator, a capacity indicator, a priority indicator for an associated indirect communication path, and an energy status indicator, wherein each of the parameters relates to one of the candidate indirect connection paths.

47. The method according to any of embodiments 37-46, wherein providing the obtained path information comprises sending the path information directly to the network node.

48. The method according to any of embodiments 37-46, wherein providing the obtained information comprises sending the information to the network node via one or more relay wireless devices.

49. The method according to any of embodiments 37-48, wherein the method further comprises: receiving, from the network node, an indication of at least one relay wireless device selected to provide an indirect connection path between the network node and the first wireless device via the at least one selected relay wireless device; and providing the indication to the first wireless device.

50. The method according to any of embodiments 37-49, wherein the indication is transmitted in one or more of: a discovery message, a system information block, SIB, message, a Radio Resource Control, RRC, message, a PC5- RRC message, a Medium Access Control, MAC, Control Element, CE, a control Protocol Data Unit of the adaptation layer, a physical, PHY, layer signalling message, and a Sidelink Control Information, SCI, message.

51 . The method of any of the previous Group A embodiments, further comprising: obtaining user data; and forwarding the user data to a host via the transmission to the network node.

UE-triggered solutions

The following Group C Embodiments and Group D Embodiments relate to the UE-triggered solutions.

Group C Embodiments

52. A method performed in a first wireless device for selecting one or more relay wireless devices to provide an indirect connection path between a network node and the first wireless device via the selected one or more relay wireless devices, the method comprising: obtaining information relating to a plurality of direct communication links between any of: the network node, the first wireless device and one or more candidate relay wireless devices, wherein the plurality of direct communication links provide at least one candidate indirect connection path between the network node and the first wireless device; and selecting at least one of the one or more candidate relay wireless devices to provide the indirect connection path between the network node and the first wireless device, wherein the selection is based on path information relating to the at least one candidate indirect connection paths that is determined from the obtained information.

53. The method according to embodiment 52, wherein the obtained information comprises link information for the plurality of direct communication links, and wherein the step of selecting comprises: determining path information relating to the one or more candidate indirect connection paths between the network node and the first wireless device from the link information. 54. The method according to embodiment 52, wherein the obtained information comprises path information relating to the one or more candidate indirect connection paths.

55. The method according to any of embodiments 52-54, wherein the obtained information relates to a quality and/or performance of the direct communication links and/or a quality and/or performance of an indirect connection path.

56. The method according to any of embodiments 52-55, wherein the information is received from one or more candidate relay wireless devices.

57. The method according to any of embodiments 52-55 wherein the information is received from the network node.

58. The method according to any of embodiments 52-57, wherein the step of obtaining comprises: performing measurements of respective direct communication links between the first wireless device and one or more of the candidate relay wireless devices.

59. The method according to any of embodiments 52-58, wherein the information is obtained via one or more of: a System Information, SI, message; radio resource control, RRC, signalling; a medium access control, MAC, control element, CE; a control protocol data unit, PDU, of an adaptation layer; physical, PHY, layer signalling; a discovery message.

60. The method according to any of embodiments 52-59, wherein the information comprises values for one or more of the following parameters: a signal quality; reference signal received power, RSRP; reference signal received quality, RSRQ; signal to noise ratio, SNR; signal to interference plus noise ratio, SI NR; latency; capacity; priority; and an energy status indicator of a candidate relay wireless device.

61 . The method according to embodiment 60, wherein the values of the one or more parameters relate to one or more candidate indirect connection paths.

62. The method according to embodiment 60, wherein the values for the one or more parameters relate to respective direct communication links comprised within one or more candidate indirect connection paths.

63. The method according to any of embodiments 52-62, wherein, prior to the step of obtaining information, the method comprises: connecting to a first relay wireless device based on information relating to a direct communication link between the first wireless device and the first relay wireless device, and performing the steps of obtaining information and selecting to select a different relay wireless device to connect to.

64. The method according to any of embodiments 52-63, wherein the step of selecting comprises using one or more criteria that are either: received from a candidate relay wireless device, received from the network node, preconfigured at the first wireless device, or stored at the first wireless device.

65. A method performed in a first relay wireless device that is configurable to operate as a relay wireless device in an indirect connection path between a network node and a first wireless device, the method comprising: obtaining path information relating to at least one candidate indirect connection path between the first wireless device and the network node via one or more relay wireless devices, wherein each candidate indirect connection path comprises a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices; and providing the obtained information to the first wireless device.

66. The method according to embodiment 65, wherein the obtained path information relates to a quality and/or performance of the direct communication links and/or a quality and/or performance of one or more indirect connection paths.

67. The method according to embodiment 65 or 66, wherein the path information is obtained from one or more other relay wireless devices or the network node.

68. The method according to any of embodiments 65-67, wherein the path information is provided directly to the first wireless device, or to the first wireless device via one or more relay wireless devices.

69. The method according to any of embodiments 65-68, wherein the information is obtained and/or provided via one or more of: a System Information, SI, message; radio resource control, RRC, signalling; a medium access control, MAC, control element, CE; a control protocol data unit, PDU, of an adaptation layer; physical, PHY, layer signalling; a discovery message.

70. The method according to any of embodiments 65-69, wherein the information comprises values for one or more of the following parameters: a signal quality; reference signal received power, RSRP; reference signal received quality, RSRQ; signal to noise ratio, SNR; signal to interference plus noise ratio, SINR; latency; capacity; priority; and an energy status indicator of a candidate relay wireless device. 71 . The method according to embodiment 70, wherein the values of the one or more parameters relate to one or more candidate indirect connection paths.

72. The method according to embodiment 70, wherein the values for the one or more parameters relate to respective direct communication links comprised within one or more candidate indirect connection paths.

73. The method according to any of embodiments 65-72, wherein the step of obtaining comprises performing measurements of the one or more direct communication links between the second wireless device and any of the network node and one or more other candidate relay wireless devices, and/or a direct communication link between the second wireless device and the first wireless device.

74. The method according to embodiment 73, wherein the method further comprises: receiving a measurement configuration from the network node, wherein the measurement configuration defines one or more measurements that the second wireless device is to perform of the one or more direct communication links.

75. The method according to any of embodiments 65-74, wherein the step of obtaining path information is performed periodically, in response to the occurrence of a triggering event, or in response to receipt of a request from the network node or a wireless device.

76. The method according to any of embodiments 65-75, wherein the method further comprises: sending one or more criteria to the first wireless device to be used in selecting relay wireless devices for an indirect connection path.

77. The method of any of embodiments 65-76, further comprising: providing user data; and forwarding the user data to a host via a transmission to the network node.

Group D Embodiments

78. A method performed in a network node that is configurable to communicate with a first wireless device via an indirect connection path via one or more relay devices, the method comprising: obtaining path information relating to at least one candidate indirect connection path between the network node and the first wireless device via one or more candidate relay wireless devices, wherein each candidate indirect connection path comprises a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices; and providing the obtained information to the first wireless device.

79. The method according to embodiment 78, wherein the step of obtaining path information comprises performing measurements of one or more direct communication links between the network node and the one or more candidate relay wireless devices.

80. The method according to embodiment 78 or 79, wherein the obtained path information relates to a quality and/or performance of the direct communication links and/or a quality and/or performance of an indirect connection path.

81 . The method according to any of embodiments 78-80, wherein the path information is obtained from one or more of the candidate relay wireless devices.

82. The method according to any of embodiments 78-81, wherein the path information is provided directly to the first wireless device, or to the first wireless device via one or more relay wireless devices.

83. The method according to any of embodiments 78-82, wherein the path information is obtained and/or provided via one or more of: a System Information, SI, message; radio resource control, RRC, signalling; a medium access control, MAC, control element, CE; a control protocol data unit, PDU, of an adaptation layer; physical, PHY, layer signalling; a discovery message.

84. The method according to any of embodiments 78-83, wherein the path information comprises values for one or more of the following parameters: a signal quality; reference signal received power, RSRP; reference signal received quality, RSRQ; signal to noise ratio, SNR; signal to interference plus noise ratio, SI NR; latency; capacity; priority; and an energy status indicator of a candidate relay wireless device.

85. The method according to embodiment 84, wherein the values of the one or more parameters relate to the one or more candidate indirect connection paths.

86. The method according to embodiment 84, wherein the values for the one or more parameters relate to respective direct communication links comprised within the one or more candidate indirect connection paths.

87. The method according to any of embodiments 78-86, wherein the method further comprises: sending a measurement configuration to one or more wireless devices, wherein the measurement configuration defines one or more measurements that the wireless device is to perform of one or more direct communication links. 88. The method of any of embodiments 78-87, further comprising: obtaining user data; and forwarding the user data to a host or to the first wireless device.

Group E Embodiments

The following Group E Embodiments are applicable to both the network-triggered and the UE-triggered solutions.

52. A computer program product comprising a computer readable medium having computer readable code embodied therein, the computer readable code being configured such that, on execution by a suitable computer or processor, the computer or processor is caused to perform the method of any of the Group A embodiments, the Group B embodiments, the Group C embodiments or the Group D embodiments.

53. A user equipment, UE, configured to perform the method of any of the Group A embodiments or the Group C embodiments.

54. A user equipment, UE, comprising a processor and a memory, said memory containing instructions executable by said processor whereby said UE is operative to perform the method of any of the Group A embodiments or the Group C embodiments.

55. A first radio access network, RAN, node, configured to perform the method of any of the Group B embodiments or the Group D embodiments.

56. A first radio access network, RAN, node comprising a processor and a memory, said memory containing instructions executable by said processor whereby said first RAN node is operative to perform the method of any of the Group B embodiments or the Group D embodiments.

57. A user equipment, comprising: processing circuitry configured to cause the user equipment to perform any of the steps of any of the Group A embodiments or the Group C embodiments; and power supply circuitry configured to supply power to the processing circuitry.

58. A network node, the network node comprising: processing circuitry configured to cause the network node to perform any of the steps of any of the Group B embodiments or the Group D embodiments; power supply circuitry configured to supply power to the processing circuitry.

59. A user equipment (UE), the UE comprising: an antenna configured to send and receive wireless signals; radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry; the processing circuitry being configured to perform any of the steps of any of the Group A embodiments or the Group C embodiments; an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry; an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and a battery connected to the processing circuitry and configured to supply power to the UE.

60. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: 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), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A embodiments or the Group C embodiments to receive the user data from the host.

61 . The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data to the UE from the host.

62. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.

63. A method implemented by a host operating in a communication system that further includes a network node and a user equipment (UE), the method comprising: 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, wherein the UE performs any of the operations of any of the Group A embodiments or the Group C embodiments to receive the user data from the host.

64. The method of the previous embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE.

65. The method of the previous embodiment, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application.

66. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: 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), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A embodiments or the Group C embodiments to transmit the user data to the host.

67. The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data from the UE to the host.

68. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.

69. 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 comprising: at the host, receiving user data transmitted to the host via the network node by the UE, wherein the UE performs any of the steps of any of the Group A embodiments or the Group C embodiments to transmit the user data to the host. 70. The method of the previous embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE.

71. The method of the previous embodiment, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application.

72. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: 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 having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments or the Group D embodiments to transmit the user data from the host to the UE.

73. The host of the previous embodiment, wherein: the processing circuitry of the host is configured to execute a host application that provides the user data; and the UE comprises processing circuitry configured to execute a client application associated with the host application to receive the transmission of user data from the host.

74. 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 comprising: 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, wherein the network node performs any of the operations of any of the Group B embodiments or the Group D embodiments to transmit the user data from the host to the UE.

75. The method of the previous embodiment, further comprising, at the network node, transmitting the user data provided by the host for the UE. 76. The method of any of the previous 2 embodiments, wherein the user data is 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.

77. A communication system configured to provide an over-the-top service, the communication system comprising: 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 having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments or the Group D embodiments to transmit the user data from the host to the UE.

78. The communication system of the previous embodiment, further comprising: the network node; and/or the user equipment.

79. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: 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 having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments or the Group D embodiments to receive the user data from a user equipment (UE) for the host.

80. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.

81. The host of the any of the previous 2 embodiments, wherein the initiating receipt of the user data comprises requesting the user data. 82. 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 comprising: 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, wherein the network node performs any of the steps of any of the Group B embodiments or the Group D embodiments to receive the user data from the UE for the host.

83. The method of the previous embodiment, further comprising at the network node, transmitting the received user data to the host.

Claims

1. A method for selecting at least one relay wireless device to provide an indirect connection path between a network node and a first wireless device via the at least one selected relay wireless device, the method comprising: obtaining (502; 802) information relating to a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices, wherein the plurality of direct communication links provide at least one candidate indirect connection path between the network node and the first wireless device; and selecting (504; 804) at least one of the one or more candidate relay wireless devices to provide the indirect connection path between the network node and the first wireless device, wherein the selection is based on path information relating to the at least one candidate indirect connection paths that is determined from the obtained information.

2. A method as claimed in claim 1 , wherein the method is performed in the network node and the method further comprises: providing (506) an indication of the at least one selected relay wireless device to the first wireless device.

3. The method according to claim 2, wherein the obtained information relates to quality and/or performance of the direct communication links or the candidate indirect connection paths.

4. The method according to claims 2 or 3, wherein obtaining (502) the information comprises: receiving the information from one or more wireless devices.

5. The method according to claim 3 or 4, wherein the one or more wireless devices comprises the first wireless device and/or one or more candidate relay wireless devices.

6. The method according to any of claims 2-5, wherein the obtained information comprises at least one quality and/or performance measurement for each of the plurality of direct communication links.

7. The method according to any of claims 2-6, wherein obtaining (502) the information comprises: performing measurements of a direct communication link between the network node and any of: the first wireless device and one or more candidate relay wireless devices.

8. The method according to any of claims 2-7, wherein the obtained information comprises values for one or more of the following parameters: a Reference Signal Received Power, RSRP, a Reference Signal Received Quality, RSRQ, a Signal to Noise Ratio, SNR, a Signal to Interference Noise Ratio, SINR, a latency indicator, a congestion indicator, a capacity indicator, a priority indicator for an associated indirect communication path, and an energy status indicator, wherein each parameter relates to one of the plurality of direct communication links.

9. The method according to any of claims 2-5, wherein the obtained information comprises path information for each of the at least one candidate indirect connection paths.

10. The method according to claim 9, wherein the path information comprises a measure of the end-to-end quality and/or performance for each of the at least one candidate indirect connection paths.

11 . The method according to any of claims 9 or 10, wherein the path information comprises values for one or more of the following parameters: a Reference Signal Received Power, RSRP, a Reference Signal Received Quality, RSRQ, a Signal to Noise Ratio, SNR, a Signal to Interference Noise Ratio, SINR, a latency indicator, a congestion indicator, a capacity indicator, a priority indicator for an associated indirect communication path, and an energy status indicator, wherein each of the parameters relates to one of the candidate indirect connection paths.

12. The method according to any of claims 2-11 , wherein the method further comprises: prior to obtaining the information, sending an information request message to a wireless device.

13. The method according to claim 12, wherein the information request message is for configuring the wireless device to: obtain the information; and provide the information to the network node.

14. The method according to claim 12 or 13, wherein the recipient wireless device is the first wireless device and/or a candidate relay wireless device.

15. The method according to any of claims 12-14, wherein the information request message is sent directly to the recipient wireless devices.

16. The method according to any of claims 12-15, wherein the information request message is sent to the recipient wireless devices via one or more relay wireless devices.

17. The method according to any of claims 2-16, wherein providing the indication to the first wireless device comprises transmitting the indication directly to the first wireless device.

18. The method according to any of claims 2-17, wherein providing the indication to the first wireless device comprises transmitting the indication to the first wireless device via one or more relay wireless devices.

19. The method according to any of claims 2-18, wherein the indication is provided via one or more of: a system information message, a System Information Block, SIB, a Master Information Block, MIB, a discovery message, a Radio Resource Control, RRC, message, Medium Access Control, MAC, Control Element, CE, a Protocol Data Unit of the adaptation layer, and a physical, PHY, layer signalling message.

20. A method as claimed in claim 1 , wherein the method is performed in the first wireless device.

21 . The method according to claim 20, wherein the obtained information comprises link information for the plurality of direct communication links, and wherein the step of selecting (804) comprises: determining path information relating to the one or more candidate indirect connection paths between the network node and the first wireless device from the link information.

22. The method according to claim 20, wherein the obtained information comprises path information relating to the one or more candidate indirect connection paths.

23. The method according to any of claims 20-22, wherein the obtained information relates to a quality and/or performance of the direct communication links and/or a quality and/or performance of an indirect connection path.

24. The method according to any of claims 20-23, wherein the information is received from one or more candidate relay wireless devices.

25. The method according to any of claims 20-24, wherein the information is received from the network node.

26. The method according to any of claims 20-25, wherein the step of obtaining (804) comprises: performing measurements of respective direct communication links between the first wireless device and one or more of the candidate relay wireless devices.

27. The method according to any of claims 20-26, wherein the information is obtained via one or more of: a System Information, SI, message; radio resource control, RRC, signalling; a medium access control, MAC, control element, CE; a control protocol data unit, PDU, of an adaptation layer; physical, PHY, layer signalling; a discovery message.

28. The method according to any of claims 20-27, wherein the information comprises values for one or more of the following parameters: a signal quality; reference signal received power, RSRP; reference signal received quality, RSRQ; signal to noise ratio, SNR; signal to interference plus noise ratio, SINR; latency; capacity; priority; and an energy status indicator of a candidate relay wireless device.

29. The method according to claim 28, wherein the values of the one or more parameters relate to one or more candidate indirect connection paths.

30. The method according to claim 28, wherein the values for the one or more parameters relate to respective direct communication links comprised within one or more candidate indirect connection paths.

31. The method according to any of claims 20-30, wherein, prior to the step of obtaining (802) information, the method comprises: connecting to a first relay wireless device based on information relating to a direct communication link between the first wireless device and the first relay wireless device, and performing the steps of obtaining information and selecting to select a different relay wireless device to connect to.

32. The method according to any of claims 20-31 , wherein the step of selecting (804) comprises using one or more criteria that are either: received from a candidate relay wireless device, received from the network node, preconfigured at the first wireless device, or stored at the first wireless device.

33. A method performed by a wireless device, the method comprising: obtaining (602; 702; 902; 1002) path information relating to at least one candidate indirect connection path between a network node and a first wireless device via one or more relay wireless devices, wherein each candidate indirect connection path comprises a plurality of direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices; and providing (604; 704; 904; 1004) the obtained information to the network node or the first wireless device.

34. The method according to claim 33, wherein the obtained path information relates to quality and/or performance of the direct communication links or the candidate indirect connection paths.

35. The method according to claims 33 or 34, wherein the method further comprises: prior to obtaining (602; 702; 902; 1002) the path information, receiving, from the network node, an information request message.

36. The method according to claim 35, wherein the information request message is for configuring the wireless device performing the method to: obtain the path information; and provide the path information to the network node.

37. The method according to any of claims 33-36, wherein obtaining (602; 702; 902; 1002) the path information comprises: performing measurements of one or more direct communication links between the wireless device performing the method and any of: the network node, the first wireless device and one or more candidate relay wireless devices; and/or receiving, from one or more wireless devices, information relating to one or more direct communication links between any of: the network node, the first wireless device, and one or more candidate relay wireless devices.

38. The method according to claim 37, wherein the information relating to one or more direct communication links relates to quality and/or performance.

39. The method according to claim 37 or 38, wherein the information relating to one or more direct communication links comprises values for one or more of the following parameters: a Reference Signal Received Power, RSRP, a Reference Signal Received Quality, RSRQ, a Signal to Noise Ratio, SNR, a Signal to Interference Noise Ratio, SI NR, a latency indicator, a congestion indicator, a capacity indicator, a priority indicator for an associated indirect communication path, and an energy status indicator, wherein each parameter relates to one of the plurality of direct communication links.

40. The method according to any of claims 37-39, wherein obtaining (602; 702; 902; 1002) the path information further comprises: determining the path information based on the measurements and/or received information.

41 . The method according to any of claims 33-40, wherein the path information comprises a measure of the end- to-end quality and/or performance for each of the at least one candidate indirect connection paths.

42. The method according to any of claims 33-41 , wherein the path information comprises values for one or more of the following parameters: a Reference Signal Received Power, RSRP, a Reference Signal Received Quality, RSRQ, a Signal to Noise Ratio, SNR, a Signal to Interference Noise Ratio, SINR, a latency indicator, a congestion indicator, a capacity indicator, a priority indicator for an associated indirect communication path, and an energy status indicator, wherein each of the parameters relates to one of the candidate indirect connection paths.

43. The method according to any of claims 33-42, wherein providing the obtained path information comprises sending the path information directly to the network node.

44. The method according to any of claims 33-43, wherein providing the obtained information comprises sending the information to the network node via one or more relay wireless devices.

45. The method according to any of claims 33-44, wherein the method further comprises: receiving an indication of at least one relay wireless device selected to provide an indirect connection path between the network node and the first wireless device via the at least one selected relay wireless device.

46. The method according to claim 45, wherein the method further comprises: establishing an indirect connection path to the network via the at least one relay wireless device according to the received indication.

47. The method according to claim 45 or 46, wherein the indication is received in one or more of: a system information message, a System Information Block, SIB, a Master Information Block, MIB, a Radio Resource Control, RRC, message, Medium Access Control, MAC, Control Element, CE, a Protocol Data Unit of the adaptation layer, and a physical, PHY, layer signalling message, a discovery message, a PC5-RRC message, a control Protocol Data Unit of the adaptation layer, and a Sidelink Control Information, SCI, message.

48. The method according to any of claims 45-47, wherein the indication is received directly from the network node.

49. The method according to any of claims 45-48, wherein the indication is received from the network node via one or more relay wireless devices.

50. A method as claimed in any of claims 33-49, wherein the method is performed in the first wireless device, and the step of providing (604) comprises providing the obtained information to the network node.

51 . A method as claimed in any of claims 33-45, wherein the method is performed by a first relay wireless device capable of providing an indirect connection path between the network node and the first wireless device, and wherein the step of providing (704) comprises providing the obtained information to the network node.

52. The method according to claim 33, wherein the obtained path information relates to a quality and/or performance of the direct communication links and/or a quality and/or performance of one or more indirect connection paths.

53. The method according to claim 33 or 52, wherein the path information is obtained from one or more relay wireless devices or the network node.

54. The method according to any of claims 33, 52 or 53, wherein the path information is provided directly to the first wireless device, or to the first wireless device via one or more relay wireless devices.

55. The method according to any of claims 33, 52-54, wherein the information is obtained and/or provided via one or more of: a System Information, SI, message; radio resource control, RRC, signalling; a medium access control, MAC, control element, CE; a control protocol data unit, PDU, of an adaptation layer; physical, PHY, layer signalling; a discovery message.

56. The method according to any of claims 33, 52-55, wherein the information comprises values for one or more of the following parameters: a signal quality; reference signal received power, RSRP; reference signal received quality, RSRQ; signal to noise ratio, SNR; signal to interference plus noise ratio, SI NR; latency; capacity; priority; and an energy status indicator of a candidate relay wireless device.

57. The method according to claims 33, 52-56, wherein the values of the one or more parameters relate to one or more candidate indirect connection paths.

58. The method according to claim 57, wherein the values for the one or more parameters relate to respective direct communication links comprised within one or more candidate indirect connection paths.

59. A method as claimed in any of claims 33, 52-58, wherein the method is performed in a first relay wireless device that is configurable to operate as a relay wireless device in an indirect connection path between the network node and the first wireless device, and wherein the step of providing (904) comprises providing the obtained information to the first wireless device.

60. The method according to claim 59, wherein the step of obtaining (902) comprises performing measurements of the one or more direct communication links between the first relay wireless device and any of the network node and one or more other candidate relay wireless devices, and/or a direct communication link between the first relay wireless device and the first wireless device.

61 . The method according to claim 60, wherein the method further comprises: receiving a measurement configuration from the network node, wherein the measurement configuration defines one or more measurements that the first relay wireless device is to perform of the one or more direct communication links.

62. The method according to claim 60 or 61 , wherein the step of obtaining path information is performed periodically, in response to the occurrence of a triggering event, or in response to receipt of a request from the network node or a wireless device.

63. The method according to any of claims 60-62, wherein the method further comprises: sending one or more criteria to the first wireless device to be used in selecting relay wireless devices for an indirect connection path.

64. A method as claimed in claim 33, wherein the method is performed in the network node that is configurable to communicate with the first wireless device via an indirect connection path via one or more relay devices, and wherein the step of providing (1004) comprises providing the obtained information to the first wireless device.

65. The method according to claim 64, wherein the step of obtaining (1002) path information comprises performing measurements of one or more direct communication links between the network node and the one or more candidate relay wireless devices.

66. A method as claimed in claim 64 or 65, wherein the method further comprises: sending a measurement configuration to one or more wireless devices, wherein the measurement configuration defines one or more measurements that the wireless device is to perform of one or more direct communication links.

67. A computer program product comprising a computer readable medium having computer readable code embodied therein, the computer readable code being configured such that, on execution by a suitable computer or processor, the computer or processor is caused to perform the method of any of claims 1-66.

68. A wireless device (1200) configured to perform the method of any of claims 1-66.

69. A wireless device comprising a processor and a memory, said memory containing instructions executable by said processor whereby said wireless device is operative to perform the method of any of claims 1-66.

70. A network node (1300) configured to perform the method of any of any of claims 1-66.

71 . A network node comprising a processor and a memory, said memory containing instructions executable by said processor whereby said network node is operative to perform the method of any of claims 1-66.