Access control at a relay user equipment

Abstract

A relay user equipment (UE) is provided that is configured to operate as a relay between a remote UE and a network component, the relay UE performing a method. The method includes determining at least one relay capability of the relay UE, and performing a relay access control operation that indicates to the remote UE whether the remote UE is allowed to use the relay UE as the relay.

Description

BACKGROUND

[0001] A user equipment (UE) can establish a connection with at least one of multiple networks or network types. In some scenarios, the UE can communicate with a network using a direct communication link to a base station of the corresponding network. In other scenarios, the UE can communicate with a network using a UE-to-network relay. For example, the UE can establish a direct communication link with another UE that is camped on a base station of the corresponding network. In this type of arrangement, data and information sent by the UE to the network can be initially transmitted to the other UE, which then relays the data and information to the base station on behalf of the UE. For downlink communications to the UE, data and information can be initially sent to the other UE, which then relays the data and information to the UE on behalf of the network.

[0002] A UE can communicate with another UE via a sidelink. The term sidelink refers to a communication link that can be used for device-to-device communication (D2D). The other UE can be simultaneously configured with an uplink and a sidelink. From the perspective of the other UE, uplink and sidelink communications can utilize the same resources (e.g., frequency, hardware, etc.). During operation, there can be situations in which the other UE (e.g., a relay UE) can not want to operate as a relay UE for various reasons. SUMMARY

[0003] Some example embodiments include a method performed by a relay user equipment (UE) configured to operate as a relay between a remote UE and a network component. The method includes determining at least one relay capability of the relay UE and performing a relay access control operation that indicates to the remote UE whether the remote UE is allowed to use the relay UE as the relay.

[0004] Further example embodiments include a relay user equipment (UE) having a transceiver configured to establish a first communication link between the relay UE and a wireless network and a second sidelink (SL) communication link between the relay UE and a remote UE, where the relay UE is further configured to operate as a relay between the remote UE and the wireless network. The relay UE also has a processor configured to determine at least one relay capability of the UE and perform a relay access control operation that indicates to the remote UE whether the remote UE is allowed to use the relay UE as the relay.

[0005] Other example embodiments include an integrated circuit that includes a first circuit configured to determine at least one relaying capability of a user equipment (UE) that includes the integrated circuit, where the UE is configured to operate as a remote UE with a relay between the remote UE and a wireless network. The integrated circuit also includes a second circuit configured to perform a relay access control operation that indicates to the remote UE whether the remote UE is allowed to use the UE as the relay. BRIEF DESCRIPTION OF DRAWINGS

[0006] Figure 1 An example network arrangement is shown in accordance with various example embodiments.

[0007] Figure 2 An example UE that can operate as a relay UE is shown in accordance with various example embodiments.

[0008] Figure 3 A first example signaling diagram is shown in accordance with various example embodiments showing a first method of implementing access control at a relay UE including sending a relay capability to a network.

[0009] Figure 4 A second example signaling diagram is shown in accordance with various example embodiments showing further details of the first method of implementing access control at a relay UE.

[0010] Figure 5a And Figure 5b An example signaling diagram is shown in accordance with various example embodiments showing a second method of implementing access control at a relay UE based on a setup cause in an RRC connection request.

[0011] Figure 6a And Figure 6b An example signaling diagram is shown in accordance with various example embodiments showing a third method of implementing access control at a relay UE during SL one-to-one communication.

[0012] Figure 7a And Figure 7b An example signaling diagram is shown in accordance with various example embodiments showing a fourth method of implementing access control at a relay UE during a SL discovery procedure.

[0013] Figure 8a And Figure 8b An example signaling diagram is shown in accordance with various example embodiments showing a fifth method of implementing access control at a relay UE based on the relay UE detecting an event.

[0014] Figure 9a And Figure 9bExemplary signaling diagrams 900 and 950 are shown that illustrate a sixth method of implementing access control at a relay UE 112 based on link errors between the relay UE 112 and the network, in accordance with various exemplary embodiments. DETAILED DESCRIPTION

[0015] The exemplary embodiments can be further understood with reference to the following description and the related drawings, wherein like elements are referred to with the same reference numerals. The exemplary embodiments describe methods by which a relay UE can control access of remote UEs attempting to use the relay UE as a relay to the relay UE.

[0016] The exemplary embodiments are described with respect to UEs. However, the use of UEs is provided merely for illustrative purposes. The exemplary embodiments can be used with any electronic component configured with hardware, software, and / or firmware for exchanging information (e.g., control information) and / or data with a network. Thus, the UEs described herein are used to represent any suitable electronic device.

[0017] As described above, UEs can communicate directly with a base station or indirectly with a base station using a UE-to-network relay. To distinguish between UEs, reference will be made to “remote UEs” and “relay UEs.” The term “remote UE” can be used to identify a UE that will operate as a remote end point from a base station. A remote UE can connect directly to a base station or indirectly communicate with a base station using a UE-to-network relay. Throughout this specification, the terms “UE” and “remote UE” can be used interchangeably. The term “relay UE” can be used to identify a UE that can act as a relay for a remote UE. The term “relay UE” is not intended to mean that the relay UE is actively acting as a relay. Rather, the term relay UE indicates that the UE has the capability to operate as a relay for a remote UE. Further, a relay UE can also be configured to act as a remote UE at the same time. Throughout this specification, the terms “UE,” “another UE,” and “relay UE” can be used interchangeably. However, any reference to remote UEs and relay UEs is merely for illustrative purposes, and different networks can refer to similar concepts by different names.

[0018] Throughout this specification, reference to operations performed by a network can refer to operations performed at a base station, at a RAN, at a core network, by a network function, at a network service backbone, a network server, any other type of network component, or a combination thereof. Further, throughout this specification, there will be multiple examples of communications between a relay UE and a remote UE. These communications can be performed via a sidelink (SL) communication link that is a direct device-to-device communication link between UEs. However, these communications need not be via an SL link and can communicate in different direct device-to-device communication links.

[0019] When a relay UE acts as a relay for a remote UE, the relay UE should be able to perform access control for the remote UE, such as allowing or restricting the remote UE's ability to use the relay UE as a relay. There can be many reasons why a relay UE includes this capability. For example, the relay capabilities (e.g., data forwarding) of a relay UE can degrade for a variety of different reasons. For example, these reasons can include too many remote UEs using the relay UE as a relay causing congestion, poor channel quality between the relay UE and the network, capacity limitations of the communication link between the relay UE and the network (e.g., gNB), etc. Further, using a relay UE as a relay can degrade the performance of the relay UE itself, such as battery drain, reduced priority of traffic directed to the relay UE, etc. If the relay UE can perform access control to allow or restrict one or more remote UEs from using the relay UE as a relay, the relay UE can be able to selectively support certain high priority relay functions (e.g., voice forwarding, etc.). Exemplary embodiments provide various methods for a relay UE to perform access control.

[0020] Figure 1 An exemplary network arrangement 100 is shown in accordance with various exemplary embodiments. The exemplary network arrangement 100 includes UEs 110, 112. In this exemplary embodiment, UE 110 can be considered a remote UE and UE 112 can be considered a relay UE. However, as described above, any UE can act as a remote UE, a relay UE, or both. Those skilled in the art will appreciate that UEs 110, 112 can be any type of electronic component configured to communicate via a network, such as a mobile phone, a tablet, a smart phone, a phablet, an embedded device, a wearable device, an Internet of Things (IoT) device, a massive Machine Type Communication (mMTC) device, etc. It should also be appreciated that a practical network arrangement can include any number of UEs used by any number of users. Thus, the example of having two UEs 110, 112 is provided for illustrative purposes only.

[0021] UEs 110, 112 can communicate directly with one or more networks. In the example of network arrangement 100, the networks with which UEs 110, 112 can wirelessly communicate are a 5G New Radio (NR) Radio Access Network (5G NR-RAN) 120, a LTE Radio Access Network (LTE-RAN) 122, and a Wireless Local Area Network (WLAN) 124. However, UEs 110, 112 can also communicate with other types of networks, and UEs 110, 112 can also communicate with networks through a wired connection. Thus, UEs 110, 112 can include a 5G NR chipset to communicate with 5G NR-RAN 120, an LTE chipset to communicate with LTE-RAN 122, and an ISM chipset to communicate with WLAN 124.

[0022] 5G NR-RAN 120 and LTE-RAN 122 can be part of a cellular network that can be deployed by a cellular provider (e.g., Verizon, AT&T, Sprint, T-Mobile, etc.). These networks 120, 122 can include, for example, base stations (NodeBs, eNodeBs, HeNBs, eNBS, gNBs, gNodeBs, macrocell base stations, microcell base stations, small cell base stations, femtocell base stations, etc.) configured to send and receive traffic from UEs equipped with the appropriate cellular chipset. WLAN 124 can include any type of wireless local area network (WiFi, hotspots, IEEE 802.1 lx networks, etc.).

[0023] A base station (e.g., gNB 120A, eNB 122A) can include one or more communication interfaces to exchange data and / or information with an occupied UE, a corresponding RAN, a cellular core network 130, the Internet 140, etc. Further, a base station can include a processor configured to perform various operations. For example, a processor of a base station can be configured to perform operations related to link management. However, reference to a processor is merely for illustration. The operations of a base station can also be represented as individual consolidated components of the base station, or can be modular components coupled to the base station, such as an integrated circuit with or without firmware. For example, an integrated circuit can include input circuitry to receive signals and processing circuitry to process signals and other information. Further, in some base stations, the functionality of a processor is split between two or more processors, such as a baseband processor and an application processor. The example embodiments can be implemented in accordance with any of these or other configurations of a base station.

[0024] Those skilled in the art will appreciate that any associated procedures can be performed for UE 110, 112 to connect to 5G NR-RAN 120 and LTE-RAN 122. For example, as discussed above, 5G NR-RAN 120 and LTE-RAN 122 can be associated with a particular cellular provider at which UE 110, 112 and / or its user has a contract and credential information (e.g., stored on a SIM card). Upon detecting the presence of 5G NR-RAN 120, UE 110, 112 can transmit corresponding credential information in order to associate with 5G NR-RAN 120. More specifically, UE 110, 112 can associate with a particular base station (e.g., gNB 120A of 5G NR-RAN 120, eNB 122A of LTE-RAN 122).

[0025] The UEs 110, 112 can also communicate indirectly with one or more networks using UE-to-Network relay. In this example, the UE 110 can be a remote UE, and the UE 112 can be a relay UE. In this example, the relay UE 112 can camp on a gNB 120A of the 5G NR-RAN 120, and the remote UE 110 can camp on the relay UE 112. Uplink communications from the remote UE 110 can be initially transmitted to the relay UE 112 over a SL communication link. The relay UE 112 can then relay the communications to the gNB 120A on behalf of the remote UE 110. Downlink communications from the gNB 120A to the remote UE 110 can be initially sent to the relay UE 112. The relay UE 112 can then relay the communications to the remote UE 110 via the SL communication link.

[0026] In addition to the networks 120, 122, and 124, the network arrangement 100 includes a cellular core network 130, the Internet 140, an IP Multimedia Subsystem (IMS) 150, and a network services backbone 160. The cellular core network 130 can be viewed as an interconnected set of components that manage the operation and traffic of a cellular network. The cellular core network 130 also manages traffic that flows between the cellular network and the Internet 140. The IMS 150 can generally be described as an architecture for delivering multimedia services to the UEs 110 using IP protocols. The IMS 150 can communicate with the cellular core network 130 and the Internet 140 to provide multimedia services to the UEs 110. The network services backbone 160 is in direct or indirect communication with the Internet 140 and the cellular core network 130. The network services backbone 160 can generally be described as a set of components (e.g., servers, network storage arrangements, etc.) that implement a suite of services that can be used to extend the functionality of the UEs 110 in communicating with various networks.

[0027] Figure 2 An exemplary UE 112 that can operate as a relay UE is shown in accordance with various exemplary embodiments. The UE 112 will be described with reference to the network arrangement 100 of Figure 1 In this example, the UE 112 is described as it is considered a relay UE in this exemplary arrangement. However, this description can equally apply to the UE 110 or any other UE capable of acting as a relay. The UE 112 can include a processor 205, a memory arrangement 210, a display device 215, an input / output (I / O) device 220, a transceiver 225, and other components 230. The other components 230 can include, for example, a SIM card, an audio input device, an audio output device, a power source, a data acquisition device, a port for electrically connecting the UE 112 to other electronic devices, etc. Those skilled in the art will understand that the UE 112 can represent any electronic component capable of operating as a remote UE and / or a relay UE.

[0028] The processor 205 can be configured to execute a number of engines of the UE 112. For example, the engines can include an access control engine 235. The access control engine 235 can perform various operations related to allowing remote UEs to access the UE 112 as a relay UE. Examples of the various operations will be described in greater detail below.

[0029] The above engines are each merely exemplary of an application (e.g., program) executed by the processor 205. The functionality associated with the engines can also be represented as separate consolidated components of the UE 112, or can be modular components coupled to the UE 112, such as integrated circuits with or without firmware. For example, the integrated circuits can include input circuitry to receive signals and processing circuitry to process the signals and other information. The engines can also be embodied as one application or as multiple applications separate from one another. Furthermore, in some UEs, the functionality described with respect to the processor 205 is split between two or more processors, such as a baseband processor and an application processor. The example embodiments can be implemented in any of these or other configurations of the UE.

[0030] The memory arrangement 210 can be a hardware component configured to store data related to operations performed by the UE 112. The display device 215 can be a hardware component configured to display data to a user, while the I / O device 220 can be a hardware component that enables input by a user. The display device 215 and the I / O device 220 can be separate components or can be integrated together, such as a touch screen. The transceiver 225 can be a hardware component configured to establish a connection with the 5G NR-RAN 120, the LTE-RAN 122, the WLAN 124, the UE 112, and the like. Thus, the transceiver 225 can operate on a number of different frequencies or channels (e.g., a contiguous set of frequencies).

[0031] Figure 3 A first example signaling diagram 300 is shown, in accordance with various example embodiments, illustrating a first method of implementing access control at a relay UE 112, including sending a relay capability to a network. The example signaling diagram 300 will be described with reference to the network arrangement 100 of Figure 1 and the UE 112 of Figure 2 In this example, the relay UE 112 can perform access control as a relay UE by sending a relay capability to the network.

[0032] The relay UE 112 can send a relay capability message 310 to the gNB 120A to indicate the relay capabilities of the relay UE 112. As described above, the operations described herein as being performed by the gNB 120A can be performed by the gNB 120A or any other network component. In one example embodiment, the relay capability message 310 can be sent as a non-access stratum (NAS) or access stratum (AS) capability message. However, example embodiments are not limited to any particular way of sending the relay capability message 310 to the network. For example, the relay capabilities can be a minimum set of relay capabilities supported by the hardware of the relay UE 112. Some examples of these capabilities will be provided below.

[0033] The capabilities of the relay UE 112 can be pre-programmed in a subscriber identity module (SIM) card of the relay UE 112. In another example embodiment, the relay UE 112 can communicate with an application server (not shown) to receive the capabilities that can be stored in the SIM card. Some examples of the relay capabilities of the relay UE 112 can include: a maximum number of remote UEs (including remote UEs in RRC idle or RRC connected state), a maximum number of simultaneous RRC connected remote UEs, supported services (e.g., voice, high priority data, mission critical data, low latency data, etc.), details of supported services (e.g., number of simultaneous voice calls / dedicated bearers, etc.), quality of service (QoS) of remote UE protocol data unit (PDU) sessions, etc. Those skilled in the art will understand that this is not a complete list of all relay capabilities that can be sent via the relay capability message 310.

[0034] In response to the relay capability message 310, the gNB 120A can return a relay capability response message 320. The gNB 120A can authorize the relay UE 112 to be a relay UE for the full set of reported capabilities or a subset of the capabilities. If the relay UE 112 is authorized to act as a relay, the relay UE 112 will perform a relay discovery announcement procedure 330 to announce to any remote UEs that the relay UE 112 can act as a relay. For example, Figure 1 A remote UE 110 of FIG. 1 can detect the relay announcement of the relay UE 112 and understand that the relay UE 112 can act as a relay. The announcement procedure 330 can be based on the authorized capabilities received from the network in the relay capability response message 320. Those skilled in the art will understand that once the remote UE 110 discovers the relay UE 112 based on the relay discovery announcement procedure 330, any association procedure can be used to connect the remote UE 110 to the relay UE 112 to use the relay UE 112 as a relay.

[0035] The gNB 120A does not need to authorize the relay UE 112 to act as a relay for remote UEs. For example, the relay capability response message 320 can indicate that the relay UE 112 is not authorized to act as a relay. In this case, the relay UE 112 will not perform the relay discovery announcement procedure 330.

[0036] Thus, in this example, the relay UE 112 can perform access control by informing the network of the relay capabilities of the relay UE 112. The examples provided below will show how the relay UE 112 can limit access based on the capability information that the relay UE 112 provides to the network.

[0037] Figure 4 A second example signaling diagram 400 is shown in accordance with various example embodiments, showing further details of a first method of implementing access control at the relay UE 112. The example signaling diagram 400 will be described with reference to the network arrangement 100 of Figure 1 and the relay UE 112 of Figure 2 Similar to the example shown in Figure 3 the relay UE 112 can exhibit access control by sending a relay capability to the gNB 120A. This example signaling diagram 400 shows that the relay UE 112 can have the ability to renegotiate the relay capability with the network during operation.

[0038] The relay capability message 410, the relay capability response message 420, and the relay discovery announcement procedure 430 are similar to the corresponding operations described with reference to the signaling diagram 300 of Figure 3 In this example, the relay UE 112 is authorized to act as a relay, and in response to the relay discovery announcement procedure 430, each of the UEs 110a and 110b has performed a connection procedure 440, 450, respectively, to connect to the relay UE 112. As described above, the connections between the relay UE 112 and the remote UEs 110a and 110b can be implemented via SL connections. Thus, after the connection procedures 440 and 450, the relay UE 112 is connected to the UEs 110a and 110b via SL connections and acts as a relay for the remote UEs 110a and 110b to communicate with the gNB 120A.

[0039] The relay UE 112 can detect an event 460. The event 460 can include any event that the relay UE 112 determines affects the current authorized relay capabilities of the relay UE 112. Some examples of the event 460 can include the battery level of the relay UE 112 falling below a threshold, the temperature of the relay UE 112 rising above a threshold, a high-priority traffic initiation of the relay UE 112 that is intended to consume the relay UE 112, etc. Again, these are examples of the event 460, and other events can also cause the relay UE 112 to reconsider the current relay capabilities.

[0040] In response to detecting event 460, relay UE 112 can transmit another relay capability message 470 that includes modified relay capabilities of relay UE 112. The modified capabilities can include any changes to the relay capabilities transmitted in previous relay capability message 410 or the granted relay capabilities received in relay capability response message 420. For example, relay UE 112 can indicate a lower maximum number of remote UEs that relay UE 112 can act as a relay for. However, this is merely an example, and relay UE 112 can modify any number of relay capabilities.

[0041] In response to relay capability message 470, network 130 can transmit another relay capability response message 480 to grant relay capabilities of relay UE 112 based on the modified relay capabilities transmitted by relay UE 112. In this example, the granted relay capabilities in relay capability response message 480 can not include enough relay connections to accommodate both remote UE 110a and UE 110b. Thus, in this example, relay UE 112 can perform a connection release procedure 490 to release the SL connection with remote UE 110b. Those skilled in the art will appreciate that connection release procedure 490 is merely an example of an action that relay UE 112 can take as a result of the newly granted relay capabilities.

[0042] In the above example, consider that relay UE 112 detects event 460. In another example, the network (e.g., gNB 120A) can detect the event and transmit an updated relay capability response message to relay UE 112. For example, the event detected by the network can include congestion at relay UE 112, incoming high priority traffic consumed by relay UE 112, etc. In this example, the network can reevaluate the relay capabilities transmitted by relay UE 112 in relay capability message 410 and the granted relay capabilities transmitted in relay capability response message 420 and transmit a new relay capability response message with a new set of relay capabilities. Relay UE 112 can then take appropriate action based on the new set of relay capabilities.

[0043] Further, in the above example, consider that relay UE 112 receives relay capability response message 480 in response to relay capability message 470 that provides a grant for a reduced set of relay capabilities. However, relay capability response message 480 can also indicate to relay UE 112 that it is no longer granted to act as a relay UE. For example, the network can determine that the capabilities transmitted by relay UE 112 are not sufficient for relay UE 112 to act as a relay UE. From the above example, one can see how relay UE 112 can perform relay access control by transmitting relay capabilities to the network.

[0044] Figure 5a andFigure 5b Exemplary signaling diagrams 500 and 550 are shown that illustrate a second method of implementing access control at a relay UE 112 based on the establishment cause in an RRC connection request, according to various example embodiments. The exemplary signaling diagrams 500 and 550 will be described with reference to the network arrangement 100 of Figure 1 and the UE 112 of Figure 2 In this example, the relay UE 112 can perform access control based on the establishment cause in an RRC connection request from a remote UE 110.

[0045] Those skilled in the art will appreciate that when a UE attempts to establish an RRC connection with a network, the UE sends an RRC connection request. Included in the RRC connection request can be an establishment cause, e.g., a reason for attempting to establish an RRC connection state. Examples of connection causes can include emergency, high priority access, mobile terminated access, mobile originated signaling, mobile originated data, etc. The relay UE 112 can classify these causes as high priority or low priority, and control access based on the classification of the establishment cause, as described below with reference to the signaling diagrams 500 and 550. Whether a particular establishment cause is classified as high priority or low priority can be determined on a case-by-case basis.

[0046] Referring to Figure 5a The relay UE 112 can detect an event 510. For example, the event 510 can include that the relay UE 120 is experiencing congestion, the battery level of the relay UE 112 is below a threshold, etc. Also, as described above, the event 510 can be related to a condition in which the relay UE 112 can want to reevaluate the relay capabilities of the relay UE 112 (e.g., perform access control based on the current capabilities of the relay UE 112).

[0047] The relay UE 112 can receive an RRC connection request 520 from a remote UE 110. As described above, the RRC connection request will include an establishment cause. The relay UE 112 can evaluate the establishment cause 530. As described above, the relay UE 112 can classify the establishment cause as high priority or low priority. In this example, the establishment cause can be considered to be classified as high priority. Because the establishment cause is high priority, the relay UE 112 can forward the RRC connection request 540 to the gNB 130. In this example, it can be considered that the high priority establishment cause means that the remote UE 110 establishing an RRC connection that the relay UE 112 should forward the request is important enough, even if the event 510 has been detected.

[0048] Referring to Figure 5b The relay UE 112 can detect an event 560. The event 560 can be similar to the event 510 described above with reference to Figure 5aThe described event 510. The relay UE 112 can receive the RRC connection request 570 including the establishment cause from the remote UE 110. The relay UE 112 can evaluate the establishment cause 580 and classify it as high priority or low priority. In this example, the establishment cause can be considered to be classified as low priority. Because the establishment cause is low priority, the relay UE 112 can reject the RRC connection request by sending a reject message 590 to the remote UE 110. For example, the reject message 590 can be a sidelink reject message. However, other types of reject messages can also be used. The reject message 590 can include information for the remote UE 110, such as a cause for the rejection (e.g., access control), another candidate relay UE for the remote UE, etc.

[0049] In the above example, various events were described. Another type of event that can be determined by the relay UE 112 is a service type that is not allowed by the network. For example, the network can not allow voice calls via the relay UE 112 for any of a variety of reasons. The relay UE 112 can determine that voice calls are not allowed. Thus, when the relay UE 112 receives an establishment cause indicating that the reason for the RRC connection is for a voice call, the relay UE 112 can reject the request because the service is not supported. Thus, in this example, the establishment cause is not classified, but rather the type of the establishment cause is determined, and then the relay UE 112 determines whether to forward or reject the RRC connection request.

[0050] Thus, the above example illustrates ways in which the relay UE 112 can perform access control based on information included in the RRC connection request received from the remote UE 110. Based on this information, the relay UE 112 can reject the RRC connection request or forward the RRC connection request to the network.

[0051] Figure 6a And Figure 6b Exemplary signaling diagrams 600 and 650 are shown that illustrate a third method of implementing access control at the relay UE 112 during SL one-to-one communication, according to various example embodiments. The exemplary signaling diagrams 600 and 650 will be described with reference to the network arrangement 100 of FIG. 1 and the UE 112 of FIG. 2. In this example, the relay UE 112 can perform access control during SL one-to-one communication for a relay procedure between the relay UE 112 and the remote UE 110. Figure 1 Figure 2 The exemplary signaling diagrams 600 and 650 will be described with reference to the network arrangement 100 of FIG. 1 and the UE 112 of FIG. 2. In this example, the relay UE 112 can perform access control during SL one-to-one communication for a relay procedure between the relay UE 112 and the remote UE 110.

[0052] Reference is made to Figure 6a ​remote UE 110 to the relay UE 112. The relay request 610 can be sent via a SL communication link established between the remote UE 110 and the relay UE 112. The relay request 610 can include the type of service that the remote UE 110 is requesting a relay for. The relay UE 112 can then determine whether to accept or reject the relay. The determination can be based on the type of service or can be based on any other factors that the relay UE 112 uses to determine whether to accept a relay. These factors are not limited to the information provided in the relay request 610. For example, the relay UE 112 can determine that it already has multiple operating relays and, as a result, the relay UE 112 can not accept additional relay requests. As can be seen from these examples, the relay UE 112 can determine to accept or reject the relay request 610 based on any one or more factors. In this example, it can be assumed that the relay UE 112 accepts the relay request 610 and sends a relay request acceptance message 620 via the SL communication link. The relay UE 112 can then act as a relay for the remote UE 110.

[0053] Reference is made to Figure 6b The remote UE 110 sends a relay request 660 to the relay UE 112 via a SL communication link established between the remote UE 110 and the relay UE 112. As described above, the relay request 660 can include the type of service that the remote UE 110 is requesting a relay for. The relay UE 112 can then detect an event 670. Multiple examples of events have been described above and the event 670 can include any of the example events described or any other type of event that the relay UE 112 determines to be relevant to the relay request 660 (e.g., battery level, congestion, etc.). In this example, it can be assumed that, based on the detected event 670 and the type of service requested, the relay UE 112 will reject the request. As a result, the relay UE 112 will send a rejection message 680 via the SL communication link. Again, the rejection message 680 can include any type of information, such as the reason for the rejection (e.g., access control), other available relay UEs, etc.

[0054] As a result, the above examples illustrate that the relay UE 112 can determine whether to accept or reject a relay request from a remote UE 110 received via a SL communication link. The acceptance or rejection of the relay request can then also be communicated to the remote UE 110 using the SL communication link. In the above examples, various reasons for accepting or rejecting a relay request were provided. Those skilled in the art will appreciate that there can be multiple reasons for the relay UE 112 to accept or reject a relay request. The specific reasons are not relevant to this access control method. That is, this example access control method is relevant to the relay UE 112 determining whether to accept or reject a request made during a SL one-to-one communication with a remote UE 110.

[0055] Figure 7a and Figure 7b Exemplary signaling diagrams 700 and 750 are shown that illustrate a fourth method of implementing access control at a relay UE 112 during a SL discovery procedure, according to various exemplary embodiments. The exemplary signaling diagrams 700 and 750 will be described with reference to the network arrangement 100 of FIG. 1 and the UE 112 of FIG. 2. In this example, the relay UE 112 can perform access control during a SL discovery procedure. Figure 1 Figure 2 The exemplary signaling diagrams 700 and 750 will be described with reference to the network arrangement 100 of FIG. 1 and the UE 112 of FIG. 2. In this example, the relay UE 112 can perform access control during a SL discovery procedure.

[0056] As described above, when a relay UE 112 can operate as a relay, the relay UE 112 can perform a discovery procedure with any remote UE 110 that desires to use the relay UE 112 as a relay. There can be different types of discovery procedures, two examples of which will be provided below, including examples of how the relay UE 112 can perform access control during the respective discovery procedures.

[0057] Referring to FIG. 7, the relay UE 112 can transmit a discovery announcement 710. The discovery announcement 710 can include information indicating that the relay UE 112 can act as a relay UE. The discovery announcement 710 can also include conditions under which the relay UE 112 can operate as a relay UE. For example, the discovery announcement 710 can include information such as “high priority access only.” Thus, in this example, while the relay UE 112 can act as a relay UE, there are conditions regarding availability. These conditions can be determined by the relay UE 112 and can be based on any factor or combination of factors (e.g., battery level, congestion, relay UE 112 priority traffic, etc.). In another example, the network can determine conditions under which the relay UE 112 should provide relay service and signal the conditions to the relay UE 112. Figure 7a The remote UE 110 can receive the discovery announcement 710 and determine whether the remote UE 110 satisfies the conditions for using the relay UE 112 as a relay. In this example, “high priority access” can be defined to include, for example, IMS voice / video, MT signaling, MO signaling, and emergency calls. It should be understood that this is merely one possible definition of high priority access, and the specific definition can be determined on a case-by-case basis. The remote UE 110 can determine whether the services that the remote UE 110 wants to use the relay UE 112 as a relay for satisfy the conditions. If so, the remote UE 110 can issue a relay request to the relay UE 112 to act as a relay.

[0058]

[0059] ​​Those skilled in the art will appreciate that the discovery announcement 710 is generally a broadcast message that is available to all UEs within the area of the relay UE 112. That is, while the signaling diagram 700 shows the discovery announcement 710 between the relay UE 112 and the remote UE 112, other UEs can also receive the same announcement message 710.

[0060] Reference is made to Figure 7b The remote UE 110 can send a discovery request 760 to the relay UE 112. The discovery request 760 can be in response to a discovery announcement (not shown) broadcast by the relay UE 112. However, in this example embodiment, contrary to the example embodiment shown in the signaling diagram 700, the discovery announcement can not include any conditional information, e.g., an indication that the relay UE 112 can act as a relay.

[0061] In response to the discovery request, the relay UE 112 can send a discovery response 770 to the remote UE 110. The discovery response 770 can include conditions under which the relay UE 112 can operate as a relay UE. For example, the discovery response 770 can include information such as "high priority access only." Further, in this example, while the relay UE 112 can act as a relay UE, there are conditions regarding availability. Upon receiving the discovery response 770 including the corresponding conditions, the remote UE 110 can determine whether to continue the relay setup procedure. For example, if the remote UE 110 is attempting to use the relay UE 112 as a relay for a service that is considered to be high priority, the remote UE 110 can continue to attempt to establish the relay UE 112 as a relay. On the other hand, if the remote UE 110 determines that a low priority service is to be requested, the remote UE 110 can interrupt the communication with the relay UE 112 and attempt to find a different relay UE or setup a direct communication link with the network.

[0062] In the above example, the example condition is based on high priority access. However, it should be appreciated that the relay UE 112 can set any condition for granting access to a remote UE for the purpose of acting as a relay. Thus, the above example illustrates a way of controlling access based on a discovery procedure between the relay UE 112 and the remote UE 110.

[0063] Figure 8a And Figure 8b Exemplary signaling diagrams 800 and 850 are shown, in accordance with various example embodiments, illustrating a fifth method of implementing access control at a relay UE 112 based on the relay UE 112 detecting an event. Reference is made to Figure 1 the network arrangement 100 and Figure 2The example signaling diagrams 800 and 850 are described with respect to a UE 112. In this example, the relay UE 112 can perform access control by detecting an event and signaling an indication of the event to the network (e.g., gNB 120A) or the remote UE 110. Each of these example embodiments will be described below.

[0064] With reference to Figure 8a It can initially be assumed that the relay UE 112 is currently acting as a relay UE for communications between the remote UE 110 and the gNB 120A. It can also be assumed that the remote UE 110 is currently in an RRC connected state 810 that includes one or more dedicated radio bearers (DRBs) with the network. While the relay is active, the relay UE 112 can detect an event 820. Similar to the events described above, the event 820 can be any event (e.g., battery level, congestion, etc.) that the relay UE 112 determines that the relay capabilities of the relay UE 112 should be reevaluated.

[0065] When the event 820 is detected, the relay UE 112 can send an event indication message 830 to the gNB 120A. The event indication message 830 can include a specific indication of the detected event 820 or can include information indicating that the relay capabilities of the relay UE 112 are reduced. The gNB 120A can determine that the relay UE 112 has reduced relay capabilities based on the information included in the event indication message 830. Based on the determined reduced relay capabilities, the gNB 120A can send an RRC reconfiguration message 840 to the remote UE 110. The RRC reconfiguration message can modify the RRC connection, can drop some DRBs, can drop all DRBs, depending on the current relay capabilities of the relay UE 112.

[0066] With reference to Figure 8b Similar to Figure 8a It can initially be assumed that the relay UE 112 is currently acting as a relay UE for communications between the remote UE 110 and the gNB 120A, and that the remote UE 110 is currently in an RRC connected state 860 that includes one or more DRBs with the network. While the relay is active, the relay UE 112 can detect an event 870. Similar to the events described above, the event 870 can be any event (e.g., battery level, congestion, etc.) that the relay UE 112 determines that the relay capabilities of the relay UE 112 should be reevaluated.

[0067] When the event 870 is detected, the relay UE 112 can send a SL access control message 880 to the remote UE 110. The SL access control message 880 can include a specific indication of the detected event 870, or can include information indicating that the relay capabilities of the relay UE 112 are reduced. The remote UE 110 can determine that the relay UE 112 has reduced relay capabilities based on the information included in the SL access control message 880. Based on the determined reduced relay capabilities, the remote UE 110 can trigger a NAS procedure 890 with the network to re-negotiate the RRC connection. For example, via the NAS procedure 890, the remote UE 110 can request that the modification to the service or to some or all of the DRBs be dropped.

[0068] Thus, in the above example, the relay UE 112 can control access based on signaling an event to the remote UE 110 or to the network (e.g., gNB 120A) that triggers these entities to adjust the connection based on the relay capabilities of the relay UE 112.

[0069] Figure 9a And Figure 9b Exemplary signaling diagrams 900 and 950 are shown that illustrate a sixth method of implementing access control at a relay UE 112 based on a link error between the relay UE 112 and the network, in accordance with various example embodiments. The exemplary signaling diagrams 900 and 950 will be described with reference to the network arrangement 100 of Figure 1 and the UE 112 of Figure 2 In this example, the relay UE 112 can perform access control by detecting a link error between the relay UE 112 and the gNB 120A, and performing an operation to indicate the error to the remote UE 110 to indicate that the relay UE 112 is not available to act as a relay due to the error.

[0070] Reference is made to Figure 9aIt can initially be assumed that the relay UE 112 is currently in any of an RRC connected, RRC idle, or RRC inactive state 910 with the gNB 120A. Those skilled in the art will appreciate the various states that a relay UE 112 can be in relative to a gNB 112. While in this state, the communication link between the relay UE 112 and the gNB 120A can experience errors 920. Throughout this specification, the direct communication link between a UE and a base station of the 5G NR-RAN 120 can be referred to as a “Uu link.” The errors 920 on the Uu link can include any number of errors that cause the Uu link to not work properly. When the Uu link between the relay UE 112 and the gNB 120A is not working properly, the relay UE 112 cannot operate as a relay because the information that the relay UE 112 would relay (in the UL or DL) would be communicated via the Uu link. Therefore, the relay UE 112 must inform the remote UE 110 that the relay UE 112 is currently unable to act as a relay.

[0071] In this example embodiment, the relay UE 112 indicates this information to the remote UE 110 via a SL Physical Broadcast Channel (PBCH) message 930. In this way, the remote UE 110 is informed that the relay UE 112 is not available to act as a relay.

[0072] Referring again to Figure 9b It can initially be assumed that the relay UE 112 is currently in any of an RRC connected, RRC idle, or RRC inactive state 960 with the gNB 120A. While in this state, the Uu link between the relay UE 112 and the gNB 120A can experience errors 970. In this example embodiment, the relay UE 112 indicates this information to the remote UE 110 (and any other remote UEs) by stopping 980 broadcasting discovery announcements. It should be appreciated that stopping 980 does not inform the remote UE 110 of this particular problem, but rather the lack of discovery announcements indicates that the relay UE 112 is not available to act as a relay.

[0073] The above examples show that the relay UE 112 controls access by informing (directly or indirectly) the remote UE 110 that the Uu link between the relay UE 110 and the gNB 120A is experiencing errors, and therefore the relay UE 112 is not available to act as a relay.

[0074] Those skilled in the art will appreciate that the exemplary embodiments described above can be implemented in any suitable software configuration or hardware configuration, or a combination thereof. Exemplary hardware platforms for implementing the exemplary embodiments can include, for example, Intel x86-based platforms with compatible operating systems, Windows OS, Mac platforms and MAC OS, mobile devices with operating systems such as iOS, Android, and the like. In other examples, exemplary embodiments of the above-described methods can be embodied as programs including code lines stored on a non-transitory computer-readable storage medium, which, when compiled, can be executed on a processor or microprocessor.

[0075] While this patent application describes various combinations of various embodiments each having different features, those skilled in the art will appreciate that any feature of one embodiment can be combined with features of other embodiments or features that are not inconsistent with the operation or functioning of the devices of the disclosed embodiments or that do not render said functionality inconsistent, in any manner not expressly disclosed, without departing from the spirit or scope of the disclosure.

[0076] It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled in a way that minimizes risks to the privacy of the users, and that is consistent with the principles underlying applicable laws and regulations.

[0077] It will be apparent to those skilled in the art that various modifications can be made to the present disclosure without departing from the spirit or scope of the disclosure. Thus, it is intended that the present disclosure cover modifications and variations of this disclosure provided they come within the scope of the appended claims and their equivalents.

Claims

1. A method for relay access control, the method comprising: at a relay user equipment (UE) configured to operate as a relay between a remote UE and a network component: determining at least one relay capability of the relay UE; and performing a relay access control operation that indicates to the remote UE whether the remote UE is allowed to use the relay UE as the relay, wherein the relay access control operation comprises: transmitting a relay capability message to the network, the relay capability message including the at least one relay capability; receiving a granted relay capability message from the network; broadcasting a relay discovery announcement including information based on the granted relay capability message, detecting an event affecting the at least one relay capability, wherein the at least one relay capability is modified based on the event; transmitting an updated relay capability message to the network, the updated relay capability message including the modified at least one relay capability; receiving an updated granted relay capability message from the network; and performing an operation with respect to a relay link between the relay UE and the remote UE, wherein the operation is based on the updated granted relay capability message.

2. The method of claim 1, wherein the at least one relay capability is based on an event detected by the relay UE.

3. The method of claim 1, wherein the relay access control operation comprises: determining a setup cause received in a radio resource connection (RRC) request from the remote UE; and based on the setup cause, one of: (i) forwarding the RRC connection request to the network; or (ii) rejecting the RRC request, wherein the rejection includes sending a rejection message to the remote UE.

4. The method of claim 1, further comprising: receiving a relay request from the remote UE, wherein the request is received via a SL communication link between the relay UE and the remote UE; determining whether to accept or reject the request based on the at least one relay capability of the relay UE.

5. The method of claim 1, wherein the relay access control operation comprises: broadcasting a relay announcement including conditions for the remote UE to access the relay UE as the relay.

6. The method of claim 1, wherein the relay access control operation comprises: receiving a relay discovery request from the remote UE; and transmitting a discovery response message to the remote UE via a SL communication link, the discovery response message including conditions for the remote UE to access the relay UE as the relay.

7. The method of claim 1, further comprising: detecting an event affecting the at least one relay capability; and transmitting an indication of the detected event to one of the network or the remote UE, wherein the indication causes a change in RRC configuration between the remote UE and the network.

8. The method of claim 1, further comprising: determining an error on a communication link between the relay UE and the network; and ​ ​ ​ ​ ​ Based on determining the error, one of: (i) transmitting an indication of the error to the remote UE; or (ii) stopping broadcasting a relay discovery announcement.

9. A relay user equipment (UE), the relay UE comprising: a transceiver configured to establish a first communication link between the relay UE and a wireless network and a second sidelink (SL) communication link between the relay UE and a remote UE, wherein the relay UE is further configured to operate as a relay between a remote UE and the wireless network; and a processor configured to: determine at least one relay capability of the UE; and perform a relay access control operation that indicates to the remote UE whether the remote UE is allowed to use the relay UE as the relay, wherein the relay access control operation comprises: transmitting a relay capability message to the wireless network, the relay capability message comprising the at least one relay capability; receiving a granted relay capability message from the wireless network; broadcasting a relay discovery announcement comprising information based on the granted relay capability message; detecting an event affecting the at least one relay capability, wherein the at least one relay capability is modified based on the event; transmitting an updated relay capability message to the network, the updated relay capability message comprising the modified at least one relay capability; receiving an updated granted relay capability message from the network; and performing an operation with respect to a relay link between the relay UE and the remote UE, wherein the operation is based on the updated granted relay capability message.

10. The relay UE of claim 9, wherein the processor performs the relay access control operation by: determining a setup cause received in a radio resource connection (RRC) request from the remote UE; and based on the setup cause, one of: (i) forwarding the RRC connection request to the wireless network; or (ii) rejecting the RRC request, wherein the rejection comprises sending a rejection message to the remote UE.

11. The relay UE of claim 9, wherein the processor performs the relay access control operation by: receiving a relay request from the remote UE; and determining whether to accept or reject the request based on the at least one relay capability of the relay UE.

12. The relay UE of claim 9, wherein the processor performs the relay access control operation by: broadcasting a relay announcement comprising conditions for the remote UE to access the relay UE as the relay.

13. The relay UE of claim 9, wherein the processor performs the relay access control operation by: receiving a relay discovery request from the remote UE; and transmitting a discovery response message to the remote UE via a SL communication link, the discovery response message comprising conditions for the remote UE to access the relay UE as the relay.

14. The relay UE of claim 9, wherein the processor performs the relay access control operations by: detecting an event affecting the at least one relay capability; and transmitting an indication of the detected event to one of the network or the remote UE, wherein the indication causes a change in RRC configuration between the remote UE and the wireless network.

15. The relay UE of claim 9, wherein the processor performs the relay access control operations by: determining an error on the first communication link; and based on determining the error, one of: (i) transmitting an indication of the error to the remote UE; or (ii) ceasing to broadcast a relay discovery announcement.

16. An integrated circuit comprising: first circuitry configured to determine at least one relay capability of a user equipment (UE) that includes the integrated circuit, wherein the UE is configured to operate as a relay between a remote UE and a wireless network; and second circuitry configured to perform relay access control operations that indicate to the remote UE whether the remote UE is allowed to use the UE as the relay, wherein the relay access control operations comprise: transmitting a relay capability message to the wireless network, the relay capability message including the at least one relay capability; receiving a granted relay capability message from the wireless network; broadcasting a relay discovery announcement that includes information based on the granted relay capability message; detecting an event affecting the at least one relay capability, wherein the at least one relay capability is modified based on the event; transmitting an updated relay capability message to the network, the updated relay capability message including the modified at least one relay capability; receiving an updated granted relay capability message from the network; and performing operations with respect to a relay link between the relay UE and the remote UE, wherein the operations are based on the updated granted relay capability message.

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