PATENT DOCUMENT

Publication Number: US-12047826-B2
Application Number: US-201816477454-A
Country: US
Kind Code: B2

Title: Evolved node-b (eNB), user equipment (UE) and methods of switching between direct and indirect communication for a relay arrangement

Abstract:
Embodiments of an Evolved Node-B (eNB), User Equipment (UE) and methods for communication are generally described herein. The eNB may receive, from a mobility management entity (MME), a path switch trigger message that indicates an identifier of an eRelay UE for a relay arrangement for an eRemote UE. The eNB may determine whether the eRelay UE is served by the eNB. The eNB may, if it is determined that the eRelay UE is served by the eNB, transmit a radio resource control (RRC) connection reconfiguration message to the eRemote UE. The RRC connection reconfiguration message may indicate a switch from a direct communication to an indirect communication between the eRemote UE and the eNB. The indirect communication may be through the eRelay UE in accordance with the relay arrangement.

Claims:
What is claimed is: 
     
       1. A hardware processor, comprising a non-transitory computer-readable storage medium comprising instructions, configured to:
 perform discovery and selection of a relay user equipment (UE); 
 encode, for transmission from a remote UE to the relay UE, an information request message that indicates an intention of the remote UE to communicate with the relay UE in accordance with a relay arrangement; 
 decode an information response message from the relay UE, wherein the information response message indicates an identifier of the relay UE; and 
 encode, for transmission to a mobility management entity of the remote UE, different from a mobility management entity of the relay UE, via the relay UE and a base station (BS), a tracking area update request in a non-access stratum (NAS) message. 
 
     
     
       2. The hardware processor according to  claim 1 , wherein the identifier of the relay UE is a globally unique temporary identifier (GUTI). 
     
     
       3. The hardware processor according to  claim 1 , wherein the non-transitory computer-readable storage medium is further configured to cause the remote UE to: transmit the information request message to the relay UE via a PC5 interface. 
     
     
       4. The hardware processor according to  claim 1 , wherein the relay arrangement includes a sidelink communication between the remote UE and the relay UE in accordance with a Proximity-Based Services (ProSe) arrangement. 
     
     
       5. The hardware processor according to  claim 1 , wherein the non-transitory computer-readable storage medium further configured to: determine a signal quality measurement for the relay arrangement based at least partly on a reception of a connection message from the relay UE; and determine whether to communicate with the relay UE in accordance with the relay arrangement based at least partly on the signal quality measurement. 
     
     
       6. The hardware processor according to  claim 1 , wherein the remote UE is configured to operate as an Evolved Proximity-Based Services (ProSe) Remote UE, wherein the relay arrangement is an Evolved ProSe UE-to-Network Relay. 
     
     
       7. A remote user equipment (UE), comprising:
 a radio; and 
 processing circuitry, operably coupled to the radio and configured to cause the remote UE to:
 perform discovery and selection of a relay user equipment (UE); 
 encode, for transmission from a remote UE to the relay UE, an information request message that indicates an intention of the remote UE to communicate with the relay UE in accordance with a relay arrangement; 
 decode an information response message from the relay UE, wherein the information response message indicates an identifier of the relay UE; and 
 encode, for transmission to a mobility management entity of the remote UE, different from a mobility management entity of the relay UE, via the relay UE and a base station (BS), a tracking area update request in a non-access stratum (NAS) message. 
 
 
     
     
       8. The remote UE of  claim 7 , wherein the identifier of the relay UE is a globally unique temporary identifier (GUTI). 
     
     
       9. The remote UE of  claim 7 , wherein the processing circuitry is further configured to cause the remote UE to:
 transmit the information request message to the relay UE via a PC5 interface. 
 
     
     
       10. The remote UE of  claim 7 , wherein the relay arrangement includes a sidelink communication between the remote UE and the relay UE in accordance with a Proximity-Based Services (ProSe) arrangement. 
     
     
       11. The remote UE of  claim 7 , wherein the processing circuitry is further configured to cause the remote UE to:
 determine a signal quality measurement for the relay arrangement based at least partly on a reception of a connection message from the relay UE; and 
 determine whether to communicate with the relay UE in accordance with the relay arrangement based at least partly on the signal quality measurement. 
 
     
     
       12. The remote UE of  claim 7 , wherein the remote UE is configured to operate as an Evolved Proximity-Based Services (ProSe) Remote UE, wherein the relay arrangement is an Evolved ProSe UE-to-Network Relay. 
     
     
       13. A method, comprising:
 performing discovery and selection of a relay user equipment (UE); 
 encoding, for transmission from a remote UE to the relay UE, an information request message that indicates an intention of the remote UE to communicate with the relay UE in accordance with a relay arrangement; 
 decoding an information response message from the relay UE, wherein the information response message indicates an identifier of the relay UE; and 
 encoding, for transmission to a mobility management entity of the remote UE, different from a mobility management entity of the relay UE, via the relay UE and a base station (BS), a tracking area update request in a non-access stratum (NAS) message. 
 
     
     
       14. The method of  claim 13 , wherein the NAS message comprises a notification. 
     
     
       15. The method of  claim 13 , wherein the NAS message comprises an indication of whether access via layer 2 relay is enabled. 
     
     
       16. The method of  claim 13 , wherein the NAS message comprises an indication that access via layer 2 relay is enabled. 
     
     
       17. The method of  claim 13 , wherein the NAS message comprises an indication of the identifier of the relay UE. 
     
     
       18. The method of  claim 17 , wherein the identifier of the relay UE comprises a globally unique temporary identifier (GUTI). 
     
     
       19. The method of  claim 13 , wherein the NAS message comprises a request that access via layer 2 relay be disabled. 
     
     
       20. The method of  claim 13 , wherein the NAS message comprises an indication that access via layer 2 relay is to be disabled. 
     
     
       21. The method of  claim 13 , wherein the NAS message comprises:
 an indication that access via layer 2 relay is enabled; and 
 a globally unique temporary identifier (GUTI) of the relay UE. 
 
     
     
       22. The method of  claim 13 , further comprising receiving a handover command from the mobility management entity of the remote UE via the BS. 
     
     
       23. The method of  claim 13 , wherein the identifier of the relay UE is a globally unique temporary identifier (GUTI).

Description:
PRIORITY CLAIM 
     This application is a U.S. National Stage Filing under 35 U.S.C. 371 from International Application No. PCT/US2018/021134, filed Mar. 6, 2018 and published in English as WO 2018/165150 on Sep. 13, 2018, which claims the benefit of priority to U.S. Provisional Patent Application Ser. No. 62/470,088, filed Mar. 10, 2017, and to U.S. Provisional Patent Application Ser. No. 62/486,691, filed Apr. 18, 2017, all of which are incorporated herein by reference in their entirety. 
    
    
     TECHNICAL FIELD 
     Embodiments pertain to wireless communications. Some embodiments relate to wireless networks including 3GPP (Third Generation Partnership Project) networks, 3GPP LTE (Long Term Evolution) networks, and 3GPP LTE-A (LTE Advanced) networks. Some embodiments relate to Fifth Generation (5G) networks. Some embodiments relate to relay, including layer-2 relay. Some embodiments relate to direction communication. Some embodiments relate to indirection communication. 
     BACKGROUND 
     Base stations and mobile devices operating in a cellular network may exchange data. Various techniques may be used to improve capacity and/or performance, in some cases. In an example, a mobile device at a cell edge may experience performance degradation and may benefit from a relay with another mobile device. An overall benefit to the system may also be realized as a result of the relay. Accordingly, there is a general need for methods and systems to perform operations related to handover in these and other scenarios. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1 A  is a functional diagram of an example network in accordance with some embodiments; 
         FIG.  1 B  is a functional diagram of another example network in accordance with some embodiments; 
         FIG.  2    illustrates a block diagram of an example machine in accordance with some embodiments; 
         FIG.  3    illustrates a user device in accordance with some aspects; 
         FIG.  4    illustrates a base station in accordance with some aspects; 
         FIG.  5    illustrates an exemplary communication circuitry according to some aspects; 
         FIG.  6    illustrates the operation of a method of communication in accordance with some embodiments; 
         FIG.  7    illustrates the operation of another method of communication in accordance with some embodiments; 
         FIG.  8    illustrates the operation of another method of communication in accordance with some embodiments; 
         FIG.  9    illustrates example devices that may perform one or more operations in accordance with some embodiments; 
         FIG.  10    illustrates example operations in accordance with some embodiments; 
         FIG.  11    illustrates example operations in accordance with some embodiments; 
         FIG.  12    illustrates example operations in accordance with some embodiments; 
         FIG.  13    illustrates example operations in accordance with some embodiments; 
         FIG.  14 A  and  FIG.  14 B  illustrate example operations in accordance with some embodiments; 
         FIG.  15 A  and  FIG.  15 B  illustrate example operations in accordance with some embodiments; 
         FIG.  16    illustrates example operations in accordance with some embodiments; and 
         FIG.  17 A  and  FIG.  17 B  illustrate example operations in accordance with some embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     The following description and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims. 
       FIG.  1 A  is a functional diagram of an example network in accordance with some embodiments.  FIG.  1 B  is a functional diagram of another example network in accordance with some embodiments. In some embodiments, the network  100  may be a Third Generation Partnership Project (3GPP) network. In some embodiments, the network  150  may be a 3GPP network. In a non-limiting example, the network  150  may be a new radio (NR) network. It should be noted that embodiments are not limited to usage of 3GPP networks, however, as other networks may be used in some embodiments. As an example, a Fifth Generation (5G) network may be used in some cases. As another example, a New Radio (NR) network may be used in some cases. As another example, a wireless local area network (WLAN) may be used in some cases. Embodiments are not limited to these example networks, however, as other networks may be used in some embodiments. In some embodiments, a network may include one or more components shown in  FIG.  1 A . Some embodiments may not necessarily include all components shown in  FIG.  1 A , and some embodiments may include additional components not shown in  FIG.  1 A . In some embodiments, a network may include one or more components shown in  FIG.  1 B . Some embodiments may not necessarily include all components shown in  FIG.  1 B , and some embodiments may include additional components not shown in  FIG.  1 B . In some embodiments, a network may include one or more components shown in  FIG.  1 A  and one or more components shown in  FIG.  1 B . In some embodiments, a network may include one or more components shown in  FIG.  1 A , one or more components shown in  FIG.  1 B  and one or more additional components. 
     The network  100  may comprise a radio access network (RAN)  101  and the core network  120  (e.g., shown as an evolved packet core (EPC)) coupled together through an S1 interface  115 . For convenience and brevity sake, only a portion of the core network  120 , as well as the RAN  101 , is shown. In a non-limiting example, the RAN  101  may be an evolved universal terrestrial radio access network (E-UTRAN). In another non-limiting example, the RAN  101  may include one or more components of a New Radio (NR) network. In another non-limiting example, the RAN  101  may include one or more components of an E-UTRAN and one or more components of another network (including but not limited to an NR network). 
     The core network  120  may include a mobility management entity (MME)  122 , a serving gateway (serving GW)  124 , and packet data network gateway (PDN GW)  126 . In some embodiments, the network  100  may include (and/or support) one or more Evolved Node-B&#39;s (eNBs)  104  (which may operate as base stations) for communicating with User Equipment (UE)  102 . The eNBs  104  may include macro eNBs and low power (LP) eNBs, in some embodiments. 
     In some embodiments, the network  100  may include (and/or support) one or more Generation Node-B&#39;s (gNBs)  105 . In some embodiments, one or more eNBs  104  may be configured to operate as gNBs  105 . Embodiments are not limited to the number of eNBs  104  shown in  FIG.  1 A  or to the number of gNBs  105  shown in  FIG.  1 A . In some embodiments, the network  100  may not necessarily include eNBs  104 . Embodiments are also not limited to the connectivity of components shown in  FIG.  1 A . 
     It should be noted that references herein to an eNB  104  or to a gNB  105  are not limiting. In some embodiments, one or more operations, methods and/or techniques (such as those described herein) may be practiced by a base station component (and/or other component), including but not limited to a gNB  105 , an eNB  104 , a serving cell, a transmit receive point (TRP) and/or other. In some embodiments, the base station component may be configured to operate in accordance with a New Radio (NR) protocol and/or NR standard, although the scope of embodiments is not limited in this respect. In some embodiments, the base station component may be configured to operate in accordance with a Fifth Generation (5G) protocol and/or 5G standard, although the scope of embodiments is not limited in this respect. 
     In some embodiments, one or more of the UEs  102  and/or eNBs  104  may be configured to operate in accordance with an NR protocol and/or NR techniques. References to a UE  102 , eNB  104  and/or gNB  105  as part of descriptions herein are not limiting. For instance, descriptions of one or more operations, techniques and/or methods practiced by a gNB  105  are not limiting. In some embodiments, one or more of those operations, techniques and/or methods may be practiced by an eNB  104  and/or other base station component. 
     In some embodiments, the UE  102  may transmit signals (data, control and/or other) to the gNB  105 , and may receive signals (data, control and/or other) from the gNB  105 . In some embodiments, the UE  102  may transmit signals (data, control and/or other) to the eNB  104 , and may receive signals (data, control and/or other) from the eNB  104 . These embodiments will be described in more detail below. 
     The MME  122  is similar in function to the control plane of legacy Serving GPRS Support Nodes (SGSN). The MME  122  manages mobility aspects in access such as gateway selection and tracking area list management. The serving GW  124  terminates the interface toward the RAN  101 , and routes data packets between the RAN  101  and the core network  120 . In addition, it may be a local mobility anchor point for inter-eNB handovers and also may provide an anchor for inter-3GPP mobility. Other responsibilities may include lawful intercept, charging, and some policy enforcement. The serving GW  124  and the MME  122  may be implemented in one physical node or separate physical nodes. The PDN GW  126  terminates an SGi interface toward the packet data network (PDN). The PDN GW  126  routes data packets between the EPC  120  and the external PDN, and may be a key node for policy enforcement and charging data collection. It may also provide an anchor point for mobility with non-LTE accesses. The external PDN can be any kind of IP network, as well as an IP Multimedia Subsystem (IMS) domain. The PDN GW  126  and the serving GW  124  may be implemented in one physical node or separated physical nodes. 
     In some embodiments, the eNBs  104  (macro and micro) terminate the air interface protocol and may be the first point of contact for a UE  102 . In some embodiments, an eNB  104  may fulfill various logical functions for the network  100 , including but not limited to RNC (radio network controller functions) such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. 
     In some embodiments, UEs  102  may be configured to communicate Orthogonal Frequency Division Multiplexing (OFDM) communication signals with an eNB  104  and/or gNB  105  over a multicarrier communication channel in accordance with an Orthogonal Frequency Division Multiple Access (OFDMA) communication technique. In some embodiments, eNBs  104  and/or gNBs  105  may be configured to communicate OFDM communication signals with a UE  102  over a multicarrier communication channel in accordance with an OFDMA communication technique. The OFDM signals may comprise a plurality of orthogonal subcarriers. 
     The S1 interface  115  is the interface that separates the RAN  101  and the EPC  120 . It may be split into two parts: the S1-U, which carries traffic data between the eNBs  104  and the serving GW  124 , and the S1-MME, which is a signaling interface between the eNBs  104  and the MME  122 . The X2 interface is the interface between eNBs  104 . The X2 interface comprises two parts, the X2-C and X2-U. The X2-C is the control plane interface between the eNBs  104 , while the X2-U is the user plane interface between the eNBs  104 . 
     In some embodiments, similar functionality and/or connectivity described for the eNB  104  may be used for the gNB  105 , although the scope of embodiments is not limited in this respect. In a non-limiting example, the S1 interface  115  (and/or similar interface) may be split into two parts: the S1-U, which carries traffic data between the gNBs  105  and the serving GW  124 , and the S1-MME, which is a signaling interface between the gNBs  104  and the MME  122 . The X2 interface (and/or similar interface) may enable communication between eNBs  104 , communication between gNBs  105  and/or communication between an eNB  104  and a gNB  105 . 
     With cellular networks, LP cells are typically used to extend coverage to indoor areas where outdoor signals do not reach well, or to add network capacity in areas with very dense phone usage, such as train stations. As used herein, the term low power (LP) eNB refers to any suitable relatively low power eNB for implementing a narrower cell (narrower than a macro cell) such as a femtocell, a picocell, or a micro cell. Femtocell eNBs are typically provided by a mobile network operator to its residential or enterprise customers. A femtocell is typically the size of a residential gateway or smaller and generally connects to the user&#39;s broadband line. Once plugged in, the femtocell connects to the mobile operator&#39;s mobile network and provides extra coverage in a range of typically 30 to 50 meters for residential femtocells. Thus, a LP eNB might be a femtocell eNB since it is coupled through the PDN GW  126 . Similarly, a picocell is a wireless communication system typically covering a small area, such as in-building (offices, shopping malls, train stations, etc.), or more recently in-aircraft. A picocell eNB can generally connect through the X2 link to another eNB such as a macro eNB through its base station controller (BSC) functionality. Thus, LP eNB may be implemented with a picocell eNB since it is coupled to a macro eNB via an X2 interface. Picocell eNBs or other LP eNBs may incorporate some or all functionality of a macro eNB. In some cases, this may be referred to as an access point base station or enterprise femtocell. In some embodiments, various types of gNBs  105  may be used, including but not limited to one or more of the eNB types described above. 
     In some embodiments, the network  150  may include one or more components configured to operate in accordance with one or more 3GPP standards, including but not limited to an NR standard. The network  150  shown in  FIG.  1 B  may include a next generation RAN (NG-RAN)  155 , which may include one or more gNBs  105 . In some embodiments, the network  150  may include the E-UTRAN  160 , which may include one or more eNBs. The E-UTRAN  160  may be similar to the RAN  101  described herein, although the scope of embodiments is not limited in this respect. 
     In some embodiments, the network  150  may include the MME  165 . The MME  165  may be similar to the MME  122  described herein, although the scope of embodiments is not limited in this respect. The MME  165  may perform one or more operations or functionality similar to those described herein regarding the MME  122 , although the scope of embodiments is not limited in this respect. 
     In some embodiments, the network  150  may include the SGW  170 . The SGW  170  may be similar to the SGW  124  described herein, although the scope of embodiments is not limited in this respect. The SGW  170  may perform one or more operations or functionality similar to those described herein regarding the SGW  124 , although the scope of embodiments is not limited in this respect. 
     In some embodiments, the network  150  may include component(s) and/or module(s) for functionality for a user plane function (UPF) and user plane functionality for PGW (PGW-U), as indicated by  175 . some embodiments, the network  150  may include component(s) and/or module(s) for functionality for a session management function (SMF) and control plane functionality for PGW (PGW-C), as indicated by  180 . In some embodiments, the component(s) and/or module(s) indicated by  175  and/or  180  may be similar to the PGW  126  described herein, although the scope of embodiments is not limited in this respect. The the component(s) and/or module(s) indicated by  175  and/or  180  may perform one or more operations or functionality similar to those described herein regarding the PGW  126 , although the scope of embodiments is not limited in this respect. One or both of the components  170 ,  172  may perform at least a portion of the functionality described herein for the PGW  126 , although the scope of embodiments is not limited in this respect. 
     Embodiments are not limited to the number or type of components shown in  FIG.  1 B . Embodiments are also not limited to the connectivity of components shown in  FIG.  1 B . 
     In some embodiments, a downlink resource grid may be used for downlink transmissions from an eNB  104  to a UE  102 , while uplink transmission from the UE  102  to the eNB  104  may utilize similar techniques. In some embodiments, a downlink resource grid may be used for downlink transmissions from a gNB  105  to a UE  102 , while uplink transmission from the UE  102  to the gNB  105  may utilize similar techniques. The grid may be a time-frequency grid, called a resource grid or time-frequency resource grid, which is the physical resource in the downlink in each slot. Such a time-frequency plane representation is a common practice for OFDM systems, which makes it intuitive for radio resource allocation. Each column and each row of the resource grid correspond to one OFDM symbol and one OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to one slot in a radio frame. The smallest time-frequency unit in a resource grid is denoted as a resource element (RE). There are several different physical downlink channels that are conveyed using such resource blocks. With particular relevance to this disclosure, two of these physical downlink channels are the physical downlink shared channel and the physical down link control channel. 
     As used herein, the term “circuitry” may refer to, be part of, or include an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group), and/or memory (shared, dedicated, or group) that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable hardware components that provide the described functionality. In some embodiments, the circuitry may be implemented in, or functions associated with the circuitry may be implemented by, one or more software or firmware modules. In some embodiments, circuitry may include logic, at least partially operable in hardware. Embodiments described herein may be implemented into a system using any suitably configured hardware and/or software. 
       FIG.  2    illustrates a block diagram of an example machine in accordance with some embodiments. The machine  200  is an example machine upon which any one or more of the techniques and/or methodologies discussed herein may be performed. In alternative embodiments, the machine  200  may operate as a standalone device or may be connected (e.g., networked) to other machines. In a networked deployment, the machine  200  may operate in the capacity of a server machine, a client machine, or both in server-client network environments. In an example, the machine  200  may act as a peer machine in peer-to-peer (P2P) (or other distributed) network environment. The machine  200  may be a UE  102 , eNB  104 , gNB  105 , access point (AP), station (STA), user, device, mobile device, base station, personal computer (PC), a tablet PC, a set-top box (STB), a personal digital assistant (PDA), a mobile telephone, a smart phone, a web appliance, a network router, switch or bridge, or any machine capable of executing instructions (sequential or otherwise) that specify actions to be taken by that machine. Further, while only a single machine is illustrated, the term “machine” shall also be taken to include any collection of machines that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein, such as cloud computing, software as a service (SaaS), other computer cluster configurations. 
     Examples as described herein, may include, or may operate on, logic or a number of components, modules, or mechanisms. Modules are tangible entities (e.g., hardware) capable of performing specified operations and may be configured or arranged in a certain manner. In an example, circuits may be arranged (e.g., internally or with respect to external entities such as other circuits) in a specified manner as a module. In an example, the whole or part of one or more computer systems (e.g., a standalone, client or server computer system) or one or more hardware processors may be configured by firmware or software (e.g., instructions, an application portion, or an application) as a module that operates to perform specified operations. In an example, the software may reside on a machine readable medium. In an example, the software, when executed by the underlying hardware of the module, causes the hardware to perform the specified operations. 
     Accordingly, the term “module” is understood to encompass a tangible entity, be that an entity that is physically constructed, specifically configured (e.g., hardwired), or temporarily (e.g., transitorily) configured (e.g., programmed) to operate in a specified manner or to perform part or all of any operation described herein. Considering examples in which modules are temporarily configured, each of the modules need not be instantiated at any one moment in time. For example, where the modules comprise a general-purpose hardware processor configured using software, the general-purpose hardware processor may be configured as respective different modules at different times. Software may accordingly configure a hardware processor, for example, to constitute a particular module at one instance of time and to constitute a different module at a different instance of time. 
     The machine (e.g., computer system)  200  may include a hardware processor  202  (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a main memory  204  and a static memory  206 , some or all of which may communicate with each other via an interlink (e.g., bus)  208 . The machine  200  may further include a display unit  210 , an alphanumeric input device  212  (e.g., a keyboard), and a user interface (UI) navigation device  214  (e.g., a mouse). In an example, the display unit  210 , input device  212  and UI navigation device  214  may be a touch screen display. The machine  200  may additionally include a storage device (e.g., drive unit)  216 , a signal generation device  218  (e.g., a speaker), a network interface device  220 , and one or more sensors  221 , such as a global positioning system (GPS) sensor, compass, accelerometer, or other sensor. The machine  200  may include an output controller  228 , such as a serial (e.g., universal serial bus (USB), parallel, or other wired or wireless (e.g., infrared (IR), near field communication (NFC), etc.) connection to communicate or control one or more peripheral devices (e.g., a printer, card reader, etc.). 
     The storage device  216  may include a machine readable medium  222  on which is stored one or more sets of data structures or instructions  224  (e.g., software) embodying or utilized by any one or more of the techniques or functions described herein. The instructions  224  may also reside, completely or at least partially, within the main memory  204 , within static memory  206 , or within the hardware processor  202  during execution thereof by the machine  200 . In an example, one or any combination of the hardware processor  202 , the main memory  204 , the static memory  206 , or the storage device  216  may constitute machine readable media. In some embodiments, the machine readable medium may be or may include a non-transitory computer-readable storage medium. In some embodiments, the machine readable medium may be or may include a computer-readable storage medium. 
     While the machine readable medium  222  is illustrated as a single medium, the term “machine readable medium” may include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) configured to store the one or more instructions  224 . The term “machine readable medium” may include any medium that is capable of storing, encoding, or carrying instructions for execution by the machine  200  and that cause the machine  200  to perform any one or more of the techniques of the present disclosure, or that is capable of storing, encoding or carrying data structures used by or associated with such instructions. Non-limiting machine readable medium examples may include solid-state memories, and optical and magnetic media. Specific examples of machine readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., Electrically Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM)) and flash memory devices; magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; Random Access Memory (RAM); and CD-ROM and DVD-ROM disks. In some examples, machine readable media may include non-transitory machine readable media. In some examples, machine readable media may include machine readable media that is not a transitory propagating signal. 
     The instructions  224  may further be transmitted or received over a communications network  226  using a transmission medium via the network interface device  220  utilizing any one of a number of transfer protocols (e.g., frame relay, internet protocol (IP), transmission control protocol (TCP), user datagram protocol (UDP), hypertext transfer protocol (HTTP), etc.). Example communication networks may include a local area network (LAN), a wide area network (WAN), a packet data network (e.g., the Internet), mobile telephone networks (e.g., cellular networks), Plain Old Telephone (POTS) networks, and wireless data networks (e.g., Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of standards known as Wi-Fi®, IEEE 802.16 family of standards known as WiMax®), IEEE 802.15.4 family of standards, a Long Term Evolution (LTE) family of standards, a Universal Mobile Telecommunications System (UMTS) family of standards, peer-to-peer (P2P) networks, among others. In an example, the network interface device  220  may include one or more physical jacks (e.g., Ethernet, coaxial, or phone jacks) or one or more antennas to connect to the communications network  226 . In an example, the network interface device  220  may include a plurality of antennas to wirelessly communicate using at least one of single-input multiple-output (SIMO), multiple-input multiple-output (MIMO), or multiple-input single-output (MISO) techniques. In some examples, the network interface device  220  may wirelessly communicate using Multiple User MIMO techniques. The term “transmission medium” shall be taken to include any intangible medium that is capable of storing, encoding or carrying instructions for execution by the machine  200 , and includes digital or analog communications signals or other intangible medium to facilitate communication of such software. 
       FIG.  3    illustrates a user device in accordance with some aspects. In some embodiments, the user device  300  may be a mobile device. In some embodiments, the user device  300  may be or may be configured to operate as a User Equipment (UE). In some embodiments, the user device  300  may be arranged to operate in accordance with a new radio (NR) protocol. In some embodiments, the user device  300  may be arranged to operate in accordance with a Third Generation Partnership Protocol (3GPP) protocol. The user device  300  may be suitable for use as a UE  102  as depicted in  FIG.  1   , in some embodiments. It should be noted that in some embodiments, a UE, an apparatus of a UE, a user device or an apparatus of a user device may include one or more of the components shown in one or more of  FIGS.  2 ,  3 , and  5   . In some embodiments, such a UE, user device and/or apparatus may include one or more additional components. 
     In some aspects, the user device  300  may include an application processor  305 , baseband processor  310  (also referred to as a baseband module), radio front end module (RFEM)  315 , memory  320 , connectivity module  325 , near field communication (NFC) controller  330 , audio driver  335 , camera driver  340 , touch screen  345 , display driver  350 , sensors  355 , removable memory  360 , power management integrated circuit (PMIC)  365  and smart battery  370 . In some aspects, the user device  300  may be a User Equipment (UE). 
     In some aspects, application processor  305  may include, for example, one or more CPU cores and one or more of cache memory, low drop-out voltage regulators (LDOs), interrupt controllers, serial interfaces such as serial peripheral interface (SPI), inter-integrated circuit (I 2 C) or universal programmable serial interface module, real time clock (RTC), timer-counters including interval and watchdog timers, general purpose input-output (IO), memory card controllers such as secure digital/multi-media card (SD/MMC) or similar, universal serial bus (USB) interfaces, mobile industry processor interface (MIN) interfaces and Joint Test Access Group (JTAG) test access ports. 
     In some aspects, baseband module  310  may be implemented, for example, as a solder-down substrate including one or more integrated circuits, a single packaged integrated circuit soldered to a main circuit board, and/or a multi-chip module containing two or more integrated circuits. 
       FIG.  4    illustrates a base station in accordance with some aspects. In some embodiments, the base station  400  may be or may be configured to operate as an Evolved Node-B (eNB). In some embodiments, the base station  400  may be or may be configured to operate as a Generation Node-B (gNB). In some embodiments, the base station  400  may be arranged to operate in accordance with a new radio (NR) protocol. In some embodiments, the base station  400  may be arranged to operate in accordance with a Third Generation Partnership Protocol (3GPP) protocol. It should be noted that in some embodiments, the base station  400  may be a stationary non-mobile device. The base station  400  may be suitable for use as an eNB  104  as depicted in  FIG.  1   , in some embodiments. The base station  400  may be suitable for use as a gNB  105  as depicted in  FIG.  1   , in some embodiments. It should be noted that in some embodiments, an eNB, an apparatus of an eNB, a gNB, an apparatus of a gNB, a base station and/or an apparatus of a base station may include one or more of the components shown in one or more of  FIGS.  2 ,  4 , and  5   . In some embodiments, such an eNB, gNB, base station and/or apparatus may include one or more additional components. 
       FIG.  4    illustrates a base station or infrastructure equipment radio head  400  in accordance with an aspect. The base station  400  may include one or more of application processor  405 , baseband modules  410 , one or more radio front end modules  415 , memory  420 , power management circuitry  425 , power tee circuitry  430 , network controller  435 , network interface connector  440 , satellite navigation receiver module  445 , and user interface  450 . In some aspects, the base station  400  may be an Evolved Node-B (eNB), which may be arranged to operate in accordance with a 3GPP protocol, new radio (NR) protocol and/or Fifth Generation (5G) protocol. In some aspects, the base station  400  may be a generation Node-B (gNB), which may be arranged to operate in accordance with a 3GPP protocol, new radio (NR) protocol and/or Fifth Generation (5G) protocol. 
     In some aspects, application processor  405  may include one or more CPU cores and one or more of cache memory, low drop-out voltage regulators (LDOs), interrupt controllers, serial interfaces such as SPI, I 2 C or universal programmable serial interface module, real time clock (RTC), timer-counters including interval and watchdog timers, general purpose IO, memory card controllers such as SD/MMC or similar, USB interfaces, MIPI interfaces and Joint Test Access Group (JTAG) test access ports. 
     In some aspects, baseband processor  410  may be implemented, for example, as a solder-down substrate including one or more integrated circuits, a single packaged integrated circuit soldered to a main circuit board or a multi-chip module containing two or more integrated circuits. 
     In some aspects, memory  420  may include one or more of volatile memory including dynamic random access memory (DRAM) and/or synchronous dynamic random access memory (SDRAM), and nonvolatile memory (NVM) including high-speed electrically erasable memory (commonly referred to as Flash memory), phase change random access memory (PRAM), magneto-resistive random access memory (MRAM) and/or a three-dimensional cross-point memory. Memory  420  may be implemented as one or more of solder down packaged integrated circuits, socketed memory modules and plug-in memory cards. 
     In some aspects, power management integrated circuitry  425  may include one or more of voltage regulators, surge protectors, power alarm detection circuitry and one or more backup power sources such as a battery or capacitor. Power alarm detection circuitry may detect one or more of brown out (under-voltage) and surge (over-voltage) conditions. 
     In some aspects, power tee circuitry  430  may provide for electrical power drawn from a network cable to provide both power supply and data connectivity to the base station  400  using a single cable. In some aspects, network controller  435  may provide connectivity to a network using a standard network interface protocol such as Ethernet. Network connectivity may be provided using a physical connection which is one of electrical (commonly referred to as copper interconnect), optical or wireless. 
     In some aspects, satellite navigation receiver module  445  may include circuitry to receive and decode signals transmitted by one or more navigation satellite constellations such as the global positioning system (GPS), Globalnaya Navigatsionnaya Sputnikovaya Sistema (GLONASS), Galileo and/or BeiDou. The receiver  445  may provide data to application processor  405  which may include one or more of position data or time data. Application processor  405  may use time data to synchronize operations with other radio base stations. In some aspects, user interface  450  may include one or more of physical or virtual buttons, such as a reset button, one or more indicators such as light emitting diodes (LEDs) and a display screen. 
       FIG.  5    illustrates an exemplary communication circuitry according to some aspects. Circuitry  500  is alternatively grouped according to functions. Components as shown in  500  are shown here for illustrative purposes and may include other components not shown here in  FIG.  5   . In some aspects, the communication circuitry  500  may be used for millimeter wave communication, although aspects are not limited to millimeter wave communication. Communication at any suitable frequency may be performed by the communication circuitry  500  in some aspects. 
     It should be noted that a device, such as a UE  102 , eNB  104 , gNB  105 , the user device  300 , the base station  400 , the machine  200  and/or other device may include one or more components of the communication circuitry  500 , in some aspects. 
     The communication circuitry  500  may include protocol processing circuitry  505 , which may implement one or more of medium access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), radio resource control (RRC) and non-access stratum (NAS) functions. Protocol processing circuitry  505  may include one or more processing cores (not shown) to execute instructions and one or more memory structures (not shown) to store program and data information. 
     The communication circuitry  500  may further include digital baseband circuitry  510 , which may implement physical layer (PHY) functions including one or more of hybrid automatic repeat request (HARQ) functions, scrambling and/or descrambling, coding and/or decoding, layer mapping and/or de-mapping, modulation symbol mapping, received symbol and/or bit metric determination, multi-antenna port pre-coding and/or decoding which may include one or more of space-time, space-frequency or spatial coding, reference signal generation and/or detection, preamble sequence generation and/or decoding, synchronization sequence generation and/or detection, control channel signal blind decoding, and other related functions. 
     The communication circuitry  500  may further include transmit circuitry  515 , receive circuitry  520  and/or antenna array circuitry  530 . The communication circuitry  500  may further include radio frequency (RF) circuitry  525 . In an aspect of the disclosure, RF circuitry  525  may include multiple parallel RF chains for one or more of transmit or receive functions, each connected to one or more antennas of the antenna array  530 . 
     In an aspect of the disclosure, protocol processing circuitry  505  may include one or more instances of control circuitry (not shown) to provide control functions for one or more of digital baseband circuitry  510 , transmit circuitry  515 , receive circuitry  520 , and/or radio frequency circuitry  525   
     In some embodiments, processing circuitry may perform one or more operations described herein and/or other operation(s). In a non-limiting example, the processing circuitry may include one or more components such as the processor  202 , application processor  305 , baseband module  310 , application processor  405 , baseband module  410 , protocol processing circuitry  505 , digital baseband circuitry  510 , similar component(s) and/or other component(s). 
     In some embodiments, a transceiver may transmit one or more elements (including but not limited to those described herein) and/or receive one or more elements (including but not limited to those described herein). In a non-limiting example, the transceiver may include one or more components such as the radio front end module  315 , radio front end module  415 , transmit circuitry  515 , receive circuitry  520 , radio frequency circuitry  525 , similar component(s) and/or other component(s). 
     One or more antennas (such as  230 ,  312 ,  412 ,  530  and/or others) may comprise one or more directional or omnidirectional antennas, including, for example, dipole antennas, monopole antennas, patch antennas, loop antennas, microstrip antennas or other types of antennas suitable for transmission of RF signals. In some multiple-input multiple-output (MIMO) embodiments, one or more of the antennas (such as  230 ,  312 ,  412 ,  530  and/or others) may be effectively separated to take advantage of spatial diversity and the different channel characteristics that may result. 
     In some embodiments, the UE  102 , eNB  104 , gNB  105 , user device  300 , base station  400 , machine  200  and/or other device described herein may be a mobile device and/or portable wireless communication device, such as a personal digital assistant (PDA), a laptop or portable computer with wireless communication capability, a web tablet, a wireless telephone, a smartphone, a wireless headset, a pager, an instant messaging device, a digital camera, an access point, a television, a wearable device such as a medical device (e.g., a heart rate monitor, a blood pressure monitor, etc.), or other device that may receive and/or transmit information wirelessly. In some embodiments, the UE  102 , eNB  104 , gNB  105 , user device  300 , base station  400 , machine  200  and/or other device described herein may be configured to operate in accordance with 3GPP standards, although the scope of the embodiments is not limited in this respect. In some embodiments, the UE  102 , eNB  104 , gNB  105 , user device  300 , base station  400 , machine  200  and/or other device described herein may be configured to operate in accordance with new radio (NR) standards, although the scope of the embodiments is not limited in this respect. In some embodiments, the UE  102 , eNB  104 , gNB  105 , user device  300 , base station  400 , machine  200  and/or other device described herein may be configured to operate according to other protocols or standards, including IEEE 802.11 or other IEEE standards. In some embodiments, the UE  102 , eNB  104 , gNB  105 , user device  300 , base station  400 , machine  200  and/or other device described herein may include one or more of a keyboard, a display, a non-volatile memory port, multiple antennas, a graphics processor, an application processor, speakers, and other mobile device elements. The display may be an LCD screen including a touch screen. 
     Although the UE  102 , eNB  104 , gNB  105 , user device  300 , base station  400 , machine  200  and/or other device described herein may each be illustrated as having several separate functional elements, one or more of the functional elements may be combined and may be implemented by combinations of software-configured elements, such as processing elements including digital signal processors (DSPs), and/or other hardware elements. For example, some elements may comprise one or more microprocessors, DSPs, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), radio-frequency integrated circuits (RFICs) and combinations of various hardware and logic circuitry for performing at least the functions described herein. In some embodiments, the functional elements may refer to one or more processes operating on one or more processing elements. 
     Embodiments may be implemented in one or a combination of hardware, firmware and software. Embodiments may also be implemented as instructions stored on a computer-readable storage device, which may be read and executed by at least one processor to perform the operations described herein. A computer-readable storage device may include any non-transitory mechanism for storing information in a form readable by a machine (e.g., a computer). For example, a computer-readable storage device may include read-only memory (ROM), random-access memory (RAM), magnetic disk storage media, optical storage media, flash-memory devices, and other storage devices and media. Some embodiments may include one or more processors and may be configured with instructions stored on a computer-readable storage device. 
     It should be noted that in some embodiments, an apparatus used by the UE  102 , eNB  104 , gNB  105 , machine  200 , user device  300  and/or base station  400  may include various components shown in  FIGS.  2 - 5   . Accordingly, techniques and operations described herein that refer to the UE  102  may be applicable to an apparatus of a UE. In addition, techniques and operations described herein that refer to the eNB  104  may be applicable to an apparatus of an eNB. In addition, techniques and operations described herein that refer to the gNB  105  may be applicable to an apparatus of a gNB. 
     In accordance with some embodiments, the eNB  104  may receive, from a mobility management entity (MME)  122 , a path switch trigger message that indicates: an identifier of an eRelay UE  102  for a relay arrangement for an Evolved Proximity-Based Services (ProSe) Remote UE  102 . The eNB  104  may determine, based on the identifier of the eRelay UE  102 , whether the eRelay UE  102  is served by the eNB  104  or by another eNB  104 . The eNB  104  may, if it is determined that the eRelay UE  102  is served by the eNB  104 : transmit, to the Evolved ProSe Remote UE  102 , a radio resource control (RRC) connection reconfiguration message that indicates a switch from a direct communication to an indirect communication between the Evolved ProSe Remote UE  102  and the eNB  104 . The indirect communication may be through the eRelay UE  102  in accordance with the relay arrangement. These embodiments are described in more detail below. 
       FIG.  6    illustrates the operation of a method of communication in accordance with some embodiments.  FIG.  7    illustrates the operation of another method of communication in accordance with some embodiments.  FIG.  8    illustrates the operation of another method of communication in accordance with some embodiments. It is important to note that embodiments of the methods  600 ,  700 ,  800  may include additional or even fewer operations or processes in comparison to what is illustrated in  FIGS.  6 - 8   . In addition, embodiments of the methods  600 ,  700 ,  800  are not necessarily limited to the chronological order that is shown in  FIGS.  6 - 8   . In describing the methods  600 ,  700 ,  800 , reference may be made to one or more figures, although it is understood that the methods  600 ,  700 ,  800  may be practiced with any other suitable systems, interfaces and components. 
     In some embodiments, an eNB  104  may perform one or more operations of the method  600 , but embodiments are not limited to performance of the method  600  and/or operations of it by the eNB  104 . In some embodiments, another device and/or component may perform one or more operations of the method  600 . In some embodiments, another device and/or component may perform one or more operations that may be similar to one or more operations of the method  600 . In some embodiments, another device and/or component may perform one or more operations that may be reciprocal to one or more operations of the method  600 . 
     In some embodiments, a UE  102  may perform one or more operations of the method  700 , but embodiments are not limited to performance of the method  700  and/or operations of it by the UE  102 . In some embodiments, another device and/or component may perform one or more operations of the method  700 . In some embodiments, another device and/or component may perform one or more operations that may be similar to one or more operations of the method  700 . In some embodiments, another device and/or component may perform one or more operations that may be reciprocal to one or more operations of the method  700 . In some embodiments, a UE  102  may be configurable to operate as an eRelay UE, and may perform one or more operations of the method  700 . 
     In some embodiments, a UE  102  may perform one or more operations of the method  800 , but embodiments are not limited to performance of the method  800  and/or operations of it by the UE  102 . In some embodiments, another device and/or component may perform one or more operations of the method  800 . In some embodiments, another device and/or component may perform one or more operations that may be similar to one or more operations of the method  800 . In some embodiments, another device and/or component may perform one or more operations that may be reciprocal to one or more operations of the method  800 . In some embodiments, a UE  102  may be configurable to operate as an eRemote UE, and may perform one or more operations of the method  800 . 
     It should be noted that one or more operations of one of the methods  600 ,  700 ,  800  may be the same as, similar to and/or reciprocal to one or more operations of the other methods. For instance, an operation of the method  600  may be the same as, similar to and/or reciprocal to an operation of the method  700 , in some embodiments. In a non-limiting example, an operation of the method  600  may include transmission of an element (such as a frame, block, message and/or other) by the eNB  104  to the eRelay UE  102 , and an operation of the method  700  may include reception of a same element (and/or similar element) by the eRelay UE  102  from the eNB  104 . In some cases, descriptions of operations and techniques described as part of one of the methods  600 ,  700 ,  800  may be relevant to one or both of the other methods. 
     Discussion of various techniques and concepts regarding one of the methods  600 ,  700 ,  800  and/or other method may be applicable to one of the other methods, although the scope of embodiments is not limited in this respect. Such technique and concepts may include eRemote UE, eRelay UE, various messages, parameters included in the messages, relay arrangements, direct communication, indirect communication, handover and/or other. 
     In descriptions of the methods  600 ,  700 ,  800 , references to an eRemote UE and/or eRelay UE may be used for clarity, but the scope of embodiments is not limited by those references. In some embodiments, a UE  102  may be configurable to operate as either an eRemote UE or as an eRelay UE, although the scope of embodiments is not limited in this respect. In some embodiments, a UE  102  may be configurable to operate as an eRemote UE and/or an eRelay UE, although the scope of embodiments is not limited in this respect 
     The methods  600 ,  700 ,  800  and other methods described herein may refer to eNBs  104 , gNBs  105  or UEs  102  operating in accordance with 3GPP standards, 5G standards, NR standards and/or other standards. However, embodiments of those methods are not limited to just those eNBs  104 , gNBs  105  or UEs  102  and may also be practiced on other devices, such as a Wi-Fi access point (AP) or user station (STA). In addition, the methods  600 ,  700 ,  800  and other methods described herein may be practiced by wireless devices configured to operate in other suitable types of wireless communication systems, including systems configured to operate according to various IEEE standards such as IEEE 802.11. The methods  600 ,  700 ,  800  may also be applicable to an apparatus of a UE  102 , an apparatus of an eNB  104 , an apparatus of a gNB  105  and/or an apparatus of another device described above. 
     It should also be noted that embodiments are not limited by references herein (such as in descriptions of the methods  600 ,  700  and  800  and/or other descriptions herein) to transmission, reception and/or exchanging of elements such as frames, messages, requests, indicators, signals or other elements. In some embodiments, such an element may be generated, encoded or otherwise processed by processing circuitry (such as by a baseband processor included in the processing circuitry) for transmission. The transmission may be performed by a transceiver or other component, in some cases. In some embodiments, such an element may be decoded, detected or otherwise processed by the processing circuitry (such as by the baseband processor). The element may be received by a transceiver or other component, in some cases. In some embodiments, the processing circuitry and the transceiver may be included in a same apparatus. The scope of embodiments is not limited in this respect, however, as the transceiver may be separate from the apparatus that comprises the processing circuitry, in some embodiments. 
       FIG.  9    illustrates example devices that may perform one or more operations in accordance with some embodiments.  FIG.  10    illustrates example operations in accordance with some embodiments.  FIG.  11    illustrates example operations in accordance with some embodiments.  FIG.  12    illustrates example operations in accordance with some embodiments.  FIG.  13    illustrates example operations in accordance with some embodiments.  FIG.  14 A  and  FIG.  14 B  illustrate example operations in accordance with some embodiments.  FIG.  15 A  and  FIG.  15 B  illustrate example operations in accordance with some embodiments.  FIG.  16    illustrates example operations in accordance with some embodiments.  FIG.  17 A  and  FIG.  17 B  illustrate example operations in accordance with some embodiments. In references herein, “ FIG.  14   ” may include  FIG.  14 A  and  FIG.  14 B , “ FIG.  15   ” may include  FIG.  15 A  and  FIG.  15 B , and “ FIG.  17   ” may include  FIG.  17 A  and  FIG.  17 B . 
     It should be noted that the examples shown in  FIGS.  9 - 17    may illustrate some or all of the concepts and techniques described herein in some cases, but embodiments are not limited by the examples. For instance, embodiments are not limited by the name, number, type, size, ordering, arrangement of elements (such as devices, operations, messages and/or other elements) shown in  FIGS.  9 - 17   . Although some of the elements shown in the examples of  FIGS.  9 - 17    may be included in a 3GPP LTE standard, 5G standard, NR standard and/or other standard, embodiments are not limited to usage of such elements that are included in standards. 
     The methods  600 ,  700 ,  800  may be described in terms of the devices (eRemote UE  901 , eRelay UE  902 , eNB  903 , MME  904 ) shown in  FIG.  9    for clarity, but it is understood that embodiments are not limited to performance of the operations of the methods  600 ,  700 ,  800  by those devices shown in  FIG.  9   . In some embodiments, one or more devices and/or components described herein may perform one or more of the operations of the methods  600 ,  700 ,  800  (and/or other methods). In some embodiments, one or more devices and/or components shown in the figures (including but not limited to  FIG.  1 A , FIB.  1 B, and  FIGS.  2 - 5   ) described herein may perform one or more of the operations of the methods  600 ,  700 ,  800  (and/or other methods). 
     At operation  605 , the eNB  903  may exchange one or more data packets with an eRemote UE  901  as part of a direct communication between the eRemote UE  901  and the eNB  903 . In some embodiments, the eNB  903  may transmit one or more data packets (including but not limited to downlink data packets) to the eRemote UE  901  in accordance with the direct communication. The eNB  903  may receive one or more data packets (including but not limited to uplink data packets) from the eRemote UE  901  in accordance with the direct communication. 
     References herein to an eRemote UE  901  are not limiting. In some embodiments, an Evolved ProSe Remote UE may be used and/or included instead of the eRemote UE  901 . In some embodiments, the eRemote UE  901  may be an Evolved ProSe Remote UE. In some embodiments, the eRemote UE  901  may be configured to operate as an Evolved ProSe Remote UE. In some embodiments, one or more operations described herein in terms of the eRemote UE  901  may be applicable to embodiments that include an Evolved ProSe Remote UE. 
     At operation  610 , the eNB  903  may receive, from the MME  904 , a path switch trigger message that indicates an identifier of an eRelay UE  902  for a relay arrangement for the eRemote UE  901 . The path switch trigger message may be included in a 3GPP standard, in some embodiments. It should be noted that embodiments are not limited to usage of the path switch trigger message in this operation and/or other operations described herein, as any suitable messages may be used. 
     In some embodiments, the path switch trigger message may indicate that the relay arrangement is to be enabled. In some embodiments, the path switch trigger message may indicate that an indirect communication between the eNB  903  and the eRemote UE  901  is to be enabled. The indirect communication may be in accordance with a relay arrangement in which the eRelay UE  902  operates as a relay. In some embodiments, the eRelay UE  902  may operate as a relay between the eRemote UE  901  and the eNB  903 . In some embodiments, the relay arrangement may include a sidelink communication between the eRemote UE  901  and the eRelay UE  902 . In some embodiments, the relay arrangement may include a direct communication between the eRemote UE  901  and the eRelay UE  902 . In some embodiments, the relay arrangement may include communication (sidelink, direct and/or other) between the eRemote UE  901  and the eRelay UE  902  in accordance with a proximity service (ProSe) arrangement. 
     In a non-limiting example, the identifier of the eRelay UE  902  may be an eNB UE S1AP identifier. Other identifiers may be used, in some embodiments, including but not limited to an international mobile subscriber identity (IMSI), a system architecture evolution temporary mobile subscriber identity (S-TMSI) and/or a globally unique temporary identifier (GUTI). These example identifiers may be used in one or more messages and/or operations described herein. 
     References herein to a relay arrangement are not limiting. In some embodiments, the relay arrangement may be an Evolved ProSe UE-to-Network Relay. In some embodiments, an Evolved ProSe UE-to-Network Relay may be used and/or included instead of the relay arrangement. In some embodiments, one or more operations described herein in terms of the relay arrangement may be applicable to embodiments that include an Evolved ProSe UE-to-Network Relay. 
     At operation  615 , the eNB  903  may determine whether the eRelay UE  902  is served by the eNB  903  or by another eNB  903 . In some embodiments, the eNB  903  may determine this information based at least partly on an identifier of the eRelay UE  902  (including but not limited to the identifier included in the path switch trigger message). 
     At operation  620 , the eNB  903  may transmit, to the eRemote UE  901 , a radio resource control (RRC) message that indicates a switch from the direct communication to an indirect communication. At operation  625 , the eNB  903  may transmit, to the eRelay UE  902 , an RRC message that indicates the switch from the direct communication to the indirect communication. In some embodiments, one or more of the RRC messages described herein (such as in operation  620 , operation  625  and/or other operations) may be RRC connection reconfiguration messages, although the scope of embodiments is not limited in this respect. In some embodiments, the RRC messages of operations  620  and  625  may be the same or similar, although the scope of embodiments is not limited in this respect. The RRC message(s) may be included in a 3GPP standard, in some embodiments. It should be noted that embodiments are not limited to usage of RRC message(s) in this operation and/or other operations described herein, as any suitable messages may be used. 
     In some embodiments, the indirect communication may include communication, through the eRelay UE  902 , between the eRemote UE  901  and the eNB  903 . In some embodiments, the indirect communication may include communication between the eRemote UE  901  and the eNB  903  in accordance with a relay arrangement (for which the eRelay UE  902  may operate as a relay). 
     In some embodiments, one or more of operations  620 - 625  may be performed if it is determined that the eRelay UE  902  is served by the eNB  903 , although the scope of embodiments is not limited in this respect. In some embodiments, one or more of operations  620 - 625  may not necessarily be performed in cases in which it is determined that the eRelay UE  902  is served by another eNB  903 . In some embodiments, one or more of operations  620 - 625  may not necessarily be performed in cases in which it is determined that the eRelay UE  902  is not served by the eNB  903 . 
     At operation  630 , the eNB  903  may transmit, to the eRemote UE  901 , a handover command message that indicates a switch from the direct communication to an indirect communication, through the eRelay UE  902 , between the eRemote UE  901  and another eNB  903 . The handover command message may be included in a 3GPP standard, in some embodiments. It should be noted that embodiments are not limited to usage of the handover command message in this operation and/or other operations described herein, as any suitable messages may be used. 
     In some embodiments, the handover command message may indicate one or more of: a handover of the eRemote UE  901  to the other eNB  903 , an indirect communication between the eRemote UE  901  and the other eNB  903  and/or other information. In some embodiments, the indirect communication between the eRemote UE  901  and the other eNB  903  may be through the eRelay UE in accordance with a relay arrangement, although the scope of embodiments is not limited in this respect. 
     In some embodiments, operation  630  may be performed if it is determined that the eRelay UE  902  is served by the other eNB  903 , although the scope of embodiments is not limited in this respect. In some embodiments, operation  630  may not necessarily be performed in cases in which it is determined that the eRelay UE  902  is served by the eNB  903  (the eNB  903  that performs operations of the method  600 ). 
     At operation  635 , the eNB  903  may exchange one or more data packets with the eRemote UE  901  as part of the indirect communication. In some embodiments, in accordance with the indirect communication, the eNB  903  may transmit one or more data packets (including but not limited to downlink data packets) to the eRelay UE  902  to be forwarded to the eRemote UE  901 . In some embodiments, the eNB  903  may, in accordance with the indirect communication, receive one or more data packets (including but not limited to uplink data packets) from the eRelay UE  902 , wherein the data packets were received by the eRelay UE  902  from the eRemote UE  901  to be forwarded to the eNB  903 . 
     At operation  640 , the eNB  903  may receive one or more measurement reports. At operation  645 , the eNB  903  may determine whether to initiate a handover. It should be noted that some embodiments may not necessarily include one or more of operations  640 - 645 . 
     In a non-limiting example, the eNB  903  may receive one or more measurement reports from the eRemote UE  901 . The measurement reports may be received as part of the direct communication between the eRemote UE  901  and the eNB  903 . The measurement reports may indicate one or more signal quality measurements (such as signal-to-noise ratio (SNR), reference signal received power (RSRP), reference signal received quality (RSRQ) and/or other) for the direct communication between the eRemote UE  901  and the eNB  903 . The eNB  903  may determine, based at least partly on the measurement reports, whether to initiate a handover of the eRemote UE  901  to another eNB  903 . For instance, the eNB  903  may determine to initiate the handover if the signal quality measurement is less than a threshold. In some cases, the eNB  903  may determine to refrain from initiation of the handover if the signal quality measurement is greater than or equal to the threshold. 
     At operation  650 , the eNB  903  may receive, from the MME  904 , another path switch trigger message that indicates a switch from the indirect communication to direct communication. In some embodiments, the path switch trigger message may indicate that the relay arrangement is to be disabled. In some embodiments, the path switch trigger message may indicate that the indirect communication is to be disabled. In some embodiments, the path switch trigger message may be similar to the message received at operation  610 , although the scope of embodiments is no limited in this respect. It should be noted that embodiments are not limited to usage of the path switch trigger message in this operation and/or other operations described herein, as any suitable messages may be used. 
     At operation  655 , the eNB  903  may transmit, to the eRemote UE  901 , another RRC message that indicates the switch from the indirect communication to the second direct communication. In some embodiments, the RRC message may indicate that the relay arrangement is to be disabled. In some embodiments, the RRC message may indicate that the indirect communication is to be disabled. It should be noted that embodiments are not limited to usage of the RRC message in this operation and/or other operations described herein, as any suitable messages may be used. 
     In a non-limiting example, the eNB  903  may receive, from the eRemote UE  901 , one or more measurement reports received as part of the indirect communication. The measurement reports may indicate one or more signal quality measurements (such as signal-to-noise ratio (SNR), reference signal received power (RSRP), reference signal received quality (RSRQ) and/or other) for the indirect communication. The eNB  903  may determine, based at least partly on the measurement reports, whether to initiate a handover of the eRemote UE  901  to another eNB  903  for the second direct communication. In some embodiments, other information may be used by the eNB  903  (in addition to or instead of the measurement reports related to the indirect communication) to determine whether to initiate the handover. For instance, information related to signal quality measurements of a direct communication may be used. 
     In some embodiments, the eNB  903  may, as part of the relay arrangement: receive a downlink data packet from a serving gateway (SGW)  124  to be forwarded to the eRemote UE  901 ; and transmit the downlink data packet to the eRelay UE  902  to be forwarded to the eRemote UE  901 . 
     In some embodiments, an apparatus of an eNB  903  may comprise memory. The memory may be configurable to store the identifier of the eRelay UE  902 . The memory may store one or more other elements and the apparatus may use them for performance of one or more operations. The apparatus may include processing circuitry, which may perform one or more operations (including but not limited to operation(s) of the method  600  and/or other methods described herein). The processing circuitry may include a baseband processor. The baseband circuitry and/or the processing circuitry may perform one or more operations described herein, including but not limited to decoding of uplink data packets. The apparatus may include a transceiver to receive one or more uplink data packets. The transceiver may transmit and/or receive other blocks, messages and/or other elements. 
     At operation  705 , the eRelay UE  902  may exchange one or more messages as part of an establishment of a relay arrangement in which the eRelay UE  902  operates as a relay between an eRemote UE  901  and an eNB  903 . In some embodiments, the eRelay UE  902  may transmit one or more messages to the eRemote UE  901  as part of an establishment of the relay arrangement. In some embodiments, the eRelay UE  902  may transmit one or more messages to the eNB  903  as part of the establishment of the relay arrangement. In some embodiments, the eRelay UE  902  may receive one or more messages from the eRemote UE  901  as part of the establishment of the relay arrangement. In some embodiments, the eRelay UE  902  may receive one or more messages from the eNB  903  as part of the establishment of the relay arrangement. 
     In some embodiments, the eRelay UE  902  may be configured to communicate with the eRemote UE  901  and the eNB  903  in accordance with the relay arrangement. In some embodiments, the eRelay UE  902  may operate as a relay between the eRemote UE  901  and the eNB  903 . In some embodiments, the relay arrangement may include a sidelink communication between the eRemote UE  901  and the eRelay UE  902 . In some embodiments, the relay arrangement may include a direct communication between the eNB  903  and the eRelay UE  902 . In some embodiments, the relay arrangement may include communication (sidelink, direct and/or other) between the eRemote UE  901  and the eRelay UE  902  in accordance with a proximity service (ProSe) arrangement. 
     At operation  710 , the eRelay UE  902  may receive one or more uplink data packets from the eRemote UE  901 . At operation  715 , the eRelay UE  902  may transmit the uplink data packets to the eNB  903 . At operation  720 , the eRelay UE  902  may receive one or more downlink data packets from the eNB  903 . At operation  725 , the eRelay UE  902  may transmit the uplink data packets to the eRemote UE  901 . In some embodiments, one or more of operations  710 - 725  may be performed in accordance with the indirect communication. In some embodiments, one or more of operations  710 - 725  may be performed in accordance with the relay arrangement. 
     In some embodiments, the eRelay UE  902  may receive data packets from the eRemote UE  901  and may transmit and/or forward the data packets to the eNB  903  as part of the relay arrangement. In some embodiments, the eRelay UE  902  may receive data packets from the eNB  903  and may transmit and/or forward the data packets to the eRemote UE  901  as part of the relay arrangement. 
     At operation  730 , the eRelay UE  902  may receive, from the eNB, a control message that indicates a handover of the eRelay UE  901  to another network. In a non-limiting example, the eNB  903  may operate in a Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) network. The control message may indicate a handover of the eRelay UE  901  from the 3GPP LTE network to another network in accordance with a circuit switched fallback (CSFB) procedure. In another non-limiting example, the control message may indicate a handover of the eRelay UE  901  from the 3GPP LTE network to another network in accordance with a single radio voice call continuity (SRVCC) procedure. In some embodiments, the other network (to which the handover of the eRelay UE  902  is performed) may be a second generation (2G) network, although the scope of embodiments is not limited in this respect. The other network may be any type of network. Embodiments are also not limited to usage of the 3GPP LTE network as in this example, as one or more operations may be performed in cases in which the eNB  903  operates in another type of network. 
     At operation  735 , the eRelay UE  902  may determine one or more signal quality measurements. At operation  740 , the eRelay UE  902  may determine, based at least partly on the signal quality measurements, whether an interruption of coverage is expected to occur. In some embodiments, the eRelay UE  902  may determine whether the relay arrangement is to be disabled based at least partly on the signal quality measurements. In some embodiments, the eRelay UE  902  may determine whether the relay arrangement is to be disabled based at least partly on whether it is determined that the interruption of coverage is expected to occur. Embodiments are not limited to usage of the signal quality measurements to determine whether the interruption of coverage is expected to occur, as other information may be used (in addition to or instead of the signal quality measurements) in some embodiments. 
     In a non-limiting example, the eNB  903  may operate in a 3GPP LTE network. The eRelay UE  902  may determine one or more signal quality measurements based on one or more downlink signals received from the eNB  903 . The eRelay UE  902  may determine, based at least partly on the signal quality measurements, whether an interruption of coverage by the 3GPP LTE network for the eRelay UE  902  is expected to occur. For instance, the eRelay UE  902  may determine that the interruption of coverage by the 3GPP LTE network for the eRelay UE  902  is expected to occur if an average of the signal quality measurements is less than a threshold. The eRelay UE  902  may determine that the relay arrangement is to be disabled if it is determined that the interruption of coverage by the 3GPP LTE network for the eRelay UE  902  is expected to occur. Embodiments are not limited to usage of the 3GPP LTE network as in this example, as one or more operations may be performed in cases in which the eNB  903  operates in another type of network. 
     At operation  745 , the eRelay UE  902  may determine a battery level of the eRelay UE  902 . At operation  750 , the eRelay UE  902  may determine, based at least partly on the battery level, whether the relay arrangement is to be disabled. In a non-limiting example, the eNB  903  may operate in a 3GPP LTE network. The eRelay UE  902  may determine, based at least partly on the battery level, whether the relay arrangement is to be disabled. For instance, the eRelay UE  902  may determine that the relay arrangement is to be disabled if the battery level is less than a threshold. Embodiments are not limited to usage of the 3GPP LTE network as in this example, as one or more operations may be performed in cases in which the eNB  903  operates in another type of network. 
     At operation  755 , the eRelay UE  902  may transmit, to the eRemote UE  901 , a PC5 request message that indicates that the relay arrangement is to be disabled. The PC5 request message may be included in a 3GPP standard, in some embodiments. It should be noted that embodiments are not limited to usage of the PC5 request message in this operation and/or other operations described herein, as any suitable messages may be used. 
     In some embodiments, the eRelay UE  902  may transmit the PC5 request message based on the handover from the 3GPP LTE network to the other network as indicated by the control message of operation  730 . For instance, the the eRelay UE  902  may transmit the PC5 request message in response to reception of the control message of operation  730 . 
     In some embodiments, the eRelay UE  902  may transmit the PC5 request message if it is determined that the relay arrangement is to be disabled. In some embodiments, the eRelay UE  902  may transmit the PC5 request message if it is determined that an interruption of coverage by the 3GPP LTE network for the eRelay UE  902  is expected to occur. 
     In some embodiments, one or more of the operations of the method  700  may be extended to cases in which the eRelay UE  902  supports a plurality of relay arrangements with a plurality of eRemote UEs  901 . For instance, the eRelay UE  902  may be configurable to transmit and/or forward multiple messages to multiple eRemote UEs  901 . The eRelay UE  902  may be configurable to transmit and/or forward data packets to multiple eRemote UEs  901  in accordance with multiple relay arrangements. 
     In some embodiments, an apparatus of an eRelay UE  902  may comprise memory. The memory may be configurable to store at least a portion of a data packet (such as an uplink data packet, downlink data packet and/or other). The memory may store one or more other elements and the apparatus may use them for performance of one or more operations. The apparatus may include processing circuitry, which may perform one or more operations (including but not limited to operation(s) of the method  700  and/or other methods described herein). The processing circuitry may include a baseband processor. The baseband circuitry and/or the processing circuitry may perform one or more operations described herein, including but not limited to decoding of data packets and encoding of data packets. The apparatus may include a transceiver to transmit and/or receive data packets. The transceiver may transmit and/or receive other blocks, messages and/or other elements. 
     At operation  805 , the eRemote UE  901  may exchange one or more data packets with an eNB  903  as part of a direct communication between the eRemote UE  901  and the eNB  903 . At operation  810 , the eRemote UE  901  may receive, from an eRelay UE  902 , a message (including but not limited to a PC5 request message) to establish a relay arrangement in which the eRelay UE  902  is to operate as a relay. In some embodiments, the eRelay UE  902  may operate as a relay for an indirect communication between the eRemote UE  901  and the eNB  903 . In some embodiments, the relay arrangement may include a sidelink communication between the eRemote UE  901  and the eRelay UE  902 . In some embodiments, the relay arrangement may include a sidelink communication between the eRemote UE  901  and the eRelay UE  902  in accordance with a proximity service (ProSe) arrangement. 
     At operation  815 , the eRemote UE  901  may transmit an information request message to the eRelay UE  902 . In some embodiments, the information request message may indicate an intention, of the eRemote UE  901 , to communicate with the eRelay UE  902  in accordance with the relay arrangement. In some embodiments, the eRemote UE  901  may transmit the information request to the eRelay UE as part of a sidelink communication, although the scope of embodiments is not limited in this respect. The information request message may be included in a 3GPP standard, in some embodiments. It should be noted that embodiments are not limited to usage of the information request message in this operation and/or other operations described herein, as any suitable messages may be used. 
     At operation  820 , the eRemote UE  901  may receive an information response message from the eRelay UE  902 . In some embodiments, the information response message may indicate an identifier of the eRelay UE  902 . In a non-limiting example, the identifier may be a GUTI. Embodiments are not limited to usage of a GUTI, however, as other identifiers (including but not limited to an IMSI, S-TMSI and/or other) may be used in some embodiments. In some embodiments, the information response message may indicate that the eRelay UE  902  intends to communicate with the eRemote UE  901  in accordance with the relay arrangement. The information response message may be included in a 3GPP standard, in some embodiments. It should be noted that embodiments are not limited to usage of the information response message in this operation and/or other operations described herein, as any suitable messages may be used. 
     At operation  825 , the eRemote UE  901  may determine one or more signal quality measurements. At operation  830 , the eRemote UE  901  may determine whether to communicate with the eRelay UE  902  in accordance with the relay arrangement. In some embodiments, the eRemote UE  901  may determine whether to communicate with the eRelay UE  902  in accordance with the relay arrangement based at least partly on the one or more signal quality measurements. 
     In a non-limiting example, the eRemote UE  901  may determine a signal quality measurement for the direct communication. For instance, the signal quality measurement for the direct communication may be determined based at least partly on reception of one or more downlink data packets from the eNB  903 , reception of one or more signals from the eNB  903  and/or other factor(s). The eRemote UE  901  may determine a signal quality measurement for the relay arrangement. For instance, the signal quality measurement for the relay arrangement may be based at least partly on reception of the PC5 connection message from the eRelay UE  902 , reception of one or more signals from the eRelay UE  902  and/or other factor(s). The eRemote UE  901  may determine whether to communicate with the eRelay UE  902  in accordance with the relay arrangement based at least partly on one or more of: the signal quality measurement for the direct communication, and the signal quality measurement for the relay arrangement. One or more other factors, such as throughput, loading, authorization and/or other, may be used by the eRemote UE  901  (in addition to or instead of signal quality measurements) to determine whether to communicate with the eRelay UE  902  in accordance with the relay arrangement. 
     In a non-limiting example, the eRemote UE  901  may determine to communicate with the eRelay UE  902  in accordance with the relay arrangement if the signal quality measurement for the relay arrangement is greater than the signal quality measurement for the direct communication. In another non-limiting example, the eRemote UE  901  may determine to communicate with the eRelay UE  902  in accordance with the relay arrangement if a difference between the signal quality measurement for the relay arrangement and the signal quality measurement for the direct communication is greater than a threshold. 
     At operation  835 , the eRemote UE  901  may transmit a tracking area update (TAU) message that indicates an intention of the eRemote UE  901  to communicate with the eRelay UE  901  in accordance with the relay arrangement. In some embodiments, the eRemote UE  901  may transmit the TAU message to the eNB  903  to be forwarded to the MME  904 , although the scope of embodiments is not limited in this respect. The TAU message may be included in a 3GPP standard, in some embodiments. It should be noted that embodiments are not limited to usage of the TAU message in this operation and/or other operations described herein, as any suitable messages may be used. 
     In some embodiments, an apparatus of an eRemote UE  901  may comprise memory. The memory may be configurable to store the identifier of the eRelay UE  902 . The memory may store one or more other elements and the apparatus may use them for performance of one or more operations. The apparatus may include processing circuitry, which may perform one or more operations (including but not limited to operation(s) of the method  800  and/or other methods described herein). The processing circuitry may include a baseband processor. The baseband circuitry and/or the processing circuitry may perform one or more operations described herein, including but not limited to decoding of data packets and encoding of data packets. The apparatus may include a transceiver to transmit and/or receive data packets. The transceiver may transmit and/or receive other blocks, messages and/or other elements. 
     In some embodiments, a network may include and/or support an eNB  903 . In some embodiments, the network may include and/or support multiple eNBs  903 . In some embodiments, the eRemote UE  901 , the eRelay UE  902 , the eNB  903  and/or other component(s) of the network may support one or more of: a change in communication (between the eRemote UE  901  and the network) from a direct path to an indirect path; and a change in communication (between the eRemote UE  901  and the network) from an indirect path to a direct path. Such changes may be performed with a same eNB  903 , in some embodiments. Such changes may be performed with different eNBs  903 , in some embodiments. In some cases, improvements in battery efficiency, flexibility, mobility and/or other factors may be achieved as a result of such operations. 
     In some cases, service continuity for the eRemote UE  901  when communication (between the eRemote UE  901  and the network) is switched from a direct path to an indirect path may be realized. 
     In some cases (including but not limited to cases in which one or more eRemote UEs  901  access the network via an eRelay UE  902  and an intra-E-UTRAN handover for the eRelay UE  902  is performed, one or more operations may be performed in an attempt to enable service continuity for the one or more eRemote UEs  901 . For instance, one or more of the eRemote UEs  901  may be handed over to another eNB  903  together with the eRelay UE  902 . 
     One or more of the techniques, operations and/or methods described herein may be performed in different scenarios. Several non-limiting example scenarios are given below. In an example scenario, the eRemote UE  901  may switch paths between direct 3GPP communication and indirect 3GPP communication under a same eNB  903 . In another example scenario, the eRemote UE  901  may switch paths between direct 3GPP communication and indirect 3GPP communication under different eNBs  903 , and the switch may be X2 based. In another example scenario, the eRemote UE  901  may switch paths between direct 3GPP communication and indirect 3GPP communication under different eNBs  903 , and the switch may be S1 based. In another example scenario, a handover of multiple eRemote UEs  901  to another eNB  903  together with the eRelay UE  902  may be performed. 
     Non-limiting example scenarios are illustrated in  FIGS.  10 - 17   . In some embodiments, one or more operations of one of the  FIGS.  10 - 17    may be performed. It is understood that some embodiments may include one or more operations shown in one or more of the  FIGS.  10 - 17   , but may not necessarily include all operations shown and may even include one or more additional operations. In a non-limiting example, an embodiment may include one or more operations shown in one of the  FIGS.  10 - 17   , but may not necessarily include all operations shown in that figure, and may even include one or more additional operations not shown in that figure. Some embodiments may include one or more operations from two or more of  FIGS.  10 - 17   . Embodiments are not limited to the order of operations shown in  FIGS.  10 - 17   , to the type of messages shown in  FIGS.  10 - 17   , to the names of messages shown in  FIGS.  10 - 17    or to other aspects of the messages shown in  FIGS.  10 - 17   . One or more of the messages shown in  FIGS.  10 - 17    may be included in a 3GPP standard, although the scope of embodiments is not limited to usage of those messages. Embodiments are also not limited to messages that are included in a standard. In some embodiments, one or more of the messages described herein may not necessarily include all information described. In some embodiments, one or more of the messages described herein may include additional information. 
     Referring to  FIG.  10   , in the example scenario  1000 , the Remote UE  1001  may switch from direct communication (including but not limited to direct 3GPP communication) to indirect communication (including but not limited to indirect 3GPP communication) under the same eNB  1003 . 
     As indicated by  1010 , uplink data and/or downlink data may be exchanged between the eRemote UE  1001  and one or more components. This exchange may be performed in accordance with direct communication, although the scope of embodiments is not limited in this respect. 
     As indicated by “ 1 ” in  FIG.  10   , the eRelay UE  1002  and the eRemote UE  1001  may perform discovery and selection. One or more messages may be exchanged accordingly, in some embodiments. For instance, a PC5 connection may be established between the eRemote UE  1001  and the eRelay UE  1001 . 
     As indicated by “ 2 ” in  FIG.  10   , the eRemote UE  1001  may send an Information Request message to the eRelay UE  1002 . The message may include an indication related to access via layer 2 relay (such as whether it is enabled). The eRelay UE  1002  may respond with an Information Response message. The message may include an identifier (such as a GUTI and/or other) of the eRelay UE  1002 . 
     As indicated by “ 3 ” in  FIG.  10   , the eRemote UE  1001  may send a NAS message (such as a Tracking Area Update Request, a notification and/or other) to the MME  1004  of the eRemote UE  1001 . The message may include the indication of access via layer 2 relay (such as whether it is enabled and/or other information), an identifier (such as the GUTI and/or other) of the eRelay UE  1002 , and/or other information. 
     As indicated by “ 4 ” in  FIG.  10   , the MME  1004  of the eRemote UE  1001  may send a Relay Authorization Check Request message to the MME  1005  of the eRelay UE  1002 . The message may include an identifier (such as an IMSI and/or other) of the eRemote UE  1001  and/or an identifier (such as a GUTI and/or other) of the eRelay UE  1002 . In some cases, based on information (such as the GUTI and/or other) of the eRelay UE  1001 , the MME  1004  of the eRemote UE  1001  may know and/or determine the MME  1005  of the eRelay UE  1002 . The MME  1005  of the eRelay UE  1002  may check if the eRemote UE  1001  is permitted access via the eRelay UE  1002 , and may respond with a Relay Authorization Check Response message. The message may include an authorization result and an identifier of a serving eNB  1003  of the eRelay UE  1002 . 
     As indicated by “ 5 ” in  FIG.  10   , based on the response message from the MME  1005  of the eRelay UE  1002 , the MME  1004  of the eRemote UE  1001  may check if the eRemote UE  1001  and the eRelay UE  1002  are under the same eNB  1003 . If the MME  1004  of the eRemote UE  1001  knows and/or determines that the eRemote UE  1001  and the eRelay UE  1002  are under the same eNB  1003 , it may send a Path Switch Trigger message to the eNB  1003 . The message may include an indication of whether access via layer 2 relay is enabled and an identifier (such as an eNB S1AP ID and/or other) of the eNB  1003  of the eRelay  1002 . 
     As indicated by “ 6 ” in  FIG.  10   , based on the identifier of the eNB  1003  of the eRelay UE  1002 , the eNB  1003  may decide to not perform and/or initiate a handover of the eRemote UE  1001  to another eNB and may store information related to the layer 2 relay relationship between the eRelay UE  1002  and the eRemote UE  1001 . 
     As indicated by “ 7 ” in  FIG.  10   , one or more operations related to RRC connection reconfiguration between the eNB  1003  and the eRelay UE  1002  may be performed. As indicated by “ 8 ” in  FIG.  10   , one or more operations related to RRC connection reconfiguration between the eNB  1003  and the eRemote UE  1001  may be performed. 
     As indicated by  1015  in  FIG.  10   , uplink data and/or downlink data may be exchanged between the eRemote UE  1001  and one or more components. This exchange may be performed in accordance with indirect communication, although the scope of embodiments is not limited in this respect. 
     Referring to  FIG.  11   , in the example scenario  1100 , the eRemote UE  1101  may switch from indirect communication (including but not limited to indirect 3GPP communication) to direction communication (including but not limited to direct 3GPP communication) under the same eNB  1103 . 
     As indicated by  1110  in  FIG.  11   , uplink data and/or downlink data may be exchanged between the eRemote UE  1101  and one or more components. This exchange may be performed in accordance with indirect communication, although the scope of embodiments is not limited in this respect. 
     As indicated by “ 1 ” in  FIG.  11   , the eRemote UE  1101  may send a NAS message (such as a TAU Request, notification and/or other) to the MME  1104  of the eRemote UE  1101 . The message may include an indication that the access via layer 2 relay is to be disabled. The message may include a request that the access via layer 2 relay be disabled. 
     As indicated by “ 2 ” in  FIG.  11   , the MME  1104  of the eRemote UE  1101  may send a Path Switch Trigger message to the eNB  1103 . The message may indicate that the access via layer 2 relay is to be disabled. As indicated by “ 3 ” in  FIG.  11   , based on a measurement report of the eRemote UE  1101 , the eNB may decide not to perform and/or initiate a handover the eRemote UE  1101  to another eNB. 
     As indicated by  1115  in  FIG.  11   , uplink data and/or downlink data may be exchanged between the eRemote UE  1101  and one or more components. This exchange may be performed in accordance with direct communication, although the scope of embodiments is not limited in this respect. 
     As indicated by “ 5 ” in  FIG.  11   , one or more operations related to RRC connection reconfiguration between the eNB  1103  and the eRemote UE  1001  may be performed. As indicated by “ 6 ” in  FIG.  11   , a PC5 connection between the eRemote UE  1001  and the eRelay UE  1102  may be released. 
     Referring to  FIG.  12   , in the example scenario  1200 , the eRemote UE  1201  may switch from direct communication (including but not limited to direct 3GPP communication) to indirect communication (including but not limited to indirect 3GPP communication) under different eNBs. The switch may be X2 based, although the scope of embodiments is not limited in this respect. 
     As indicated by  1210  in  FIG.  12   , uplink data and/or downlink data may be exchanged between the eRemote UE  1201  and one or more components. This exchange may be performed in accordance with direct communication, although the scope of embodiments is not limited in this respect. 
     As indicated by “ 1 ” in  FIG.  12   , one or more operations may be performed for discovery and/or selection of the eRelay UE  1202 . A PC5 connection may be established between the eRemote UE  1201  and the eRelay UE  1202 . As indicated by “ 2 ” in  FIG.  12   , the eRemote UE  1201  may send an Information Request message to the eRelay UE  1202 . The message may include an indication that access via layer 2 relay is to be enabled. The eRelay UE  1202  may respond with an Information Response message. The message may include an identifier (such as a GUTI and/or other) of the eRelay UE  1202 . 
     As indicated by “ 3 ” in  FIG.  12   , the eRemote UE  1201  may send a NAS message (such as a Tracking Area Update Request, Notification and/or other) to the MME  1205  of the eRemote UE  1201  (which may be referred to as a “source MME” for clarity). The message may include the indication that access via layer 2 relay is to be enabled. The message may include an identifier (such as a GUTI and/or other) of the eRelay UE  1202 . 
     As indicated by “ 4 ” in  FIG.  12   , based on the identifier (such as the GUTI and/or other) of the eRelay UE  1202 , the MME  1205  of the eRemote UE  1201  (the source MME) may know and/or determine the MME  1206  of the eRelay UE  1202  (which may be referred to as a “target MME” for clarity). The MME  1205  of the eRemote UE  1201  may send a Relay Authorization Check Request message to the MME  1206  of the eRelay UE  1202 . The message may include the identifier (IMSI and/or other) of the eRemote UE  1201  and/or the identifier (GUTI and/or other) of the eRelay UE  1202 . The MME  1206  of the eRelay UE  1202  may check whether the eRemote UE  1201  is permitted access via the eRelay UE  1202  and may respond with a Relay Authorization Check Response message. The message may include an authorization result (such as whether the eRemote UE  1201  is permitted access via the eRelay UE  1202 ) and/or an identifier of the serving eNB  1203  of the eRelay UE  1202 . 
     As indicated by “ 5 ” in  FIG.  12   , based on the response message received from the MME  1206  of the eRelay UE  1202 , the MME  1205  of the eRemote UE  1201  may check whether the eRemote UE  1201  and the eRelay UE are under the same eNB. If the MME  1205  of the eRemote UE  1201  knows and/or determines that the eRemote UE  1201  and the eRelay UE  1202  are under different eNBs, it may send a Path Switch Trigger message to the eNB  1203  that serves the eRemote UE  1201 . The message may include an indication of whether access via layer 2 relay is enabled and/or an identifier of the eNB  1204  that serves the eRelay UE  1202 . 
     As indicated by “ 6 ” in  FIG.  12   , based on the identifier of the eNB  1204  that serves the eRelay UE  1202 , the eNB  1203  may decide whether to perform and/or initiate a handover of the eRemote UE  1201  to the eNB  1204  that serves the eRelay UE  1202 . As indicated by “ 7 ” in  FIG.  12   , one or more operations may be performed. One or more of those operations may be similar to operations included in a 3GPP standard, although the scope of embodiments is not limited in this respect. 
     As indicated by  1215  in  FIG.  12   , uplink data and/or downlink data may be exchanged between the eRemote UE  1201  and one or more components. This exchange may be performed in accordance with indirect communication, although the scope of embodiments is not limited in this respect. 
     Referring to  FIG.  13   , in the example scenario  1300 , the eRemote UE  1301  may switch from indirect communication (including but not limited to indirect 3GPP communication) to direct communication (including but not limited to direct 3GPP communication) under different eNBs. The switch may be X2 based, although the scope of embodiments is not limited in this respect. 
     As indicated by  1310  in  FIG.  13   , uplink data and/or downlink data may be exchanged between the eRemote UE  1301  and one or more components. This exchange may be performed in accordance with indirect communication, although the scope of embodiments is not limited in this respect. 
     As indicated by “ 1 ” in  FIG.  13   , the eRemote UE  1301  may send a NAS message (such as a TAU Request, notification and/or other) to the MME  1305  of the eRemote UE  1301 . The message may include an indication that access via layer 2 relay is to be disabled. The message may include a request that access via layer 2 relay be disabled. 
     As indicated by “ 2 ” in  FIG.  13   , the MME  1305  of the eRemote UE  1301  may send a Path Switch Trigger message to the eNB  1303 . The message may include an indication that access via layer 2 relay is to be disabled. As indicated by “ 3 ” in  FIG.  13   , based on a measurement report of the eRemote UE  1301 , the eNB  1303  may decide not to perform and/or initiate a handover of the eRemote UE  1301  to another eNB. 
     As indicated by “ 4 ” in  FIG.  13   , one or more operations may be performed. One or more of those operations may be similar to operations included in a 3GPP standard, although the scope of embodiments is not limited in this respect. 
     As indicated by  1315  in  FIG.  13   , uplink data and/or downlink data may be exchanged between the eRemote UE  1301  and one or more components. This exchange may be performed in accordance with direct communication, although the scope of embodiments is not limited in this respect. 
     Referring to  FIG.  14   , in the example scenario  1400 , the eRemote UE  1401  may switch from direct communication (including but not limited to direct 3GPP communication) to indirect communication (including but not limited to indirect 3GPP communication) under different eNBs. The switch may be S1 based, although the scope of embodiments is not limited in this respect. 
     As indicated by  1410  in  FIG.  14   , uplink data and/or downlink data may be exchanged between the eRemote UE  1401  and one or more components. This exchange may be performed in accordance with direct communication, although the scope of embodiments is not limited in this respect. 
     As indicated by “ 1 ” in  FIG.  14   , one or more operations related to discovery and selection of the eRelay UE  1402  may be performed. A PC5 connection may be established between the eRemote UE  1401  and the eRelay UE  1402 . As indicated by “ 2 ” in  FIG.  14   , the eRemote UE  1401  may send an Information Request message to the eRelay UE  1402 . The message may include an indication that access via layer 2 relay is to be enabled. The message may include a request that access via layer 2 relay be enabled. The eRelay UE  1402  may respond with an Information Response message. The message may include an identifier (such as a GUTI and/or other) of the eRelay UE  1402 . 
     As indicated by “ 3 ” in  FIG.  14   , the eRemote UE  1401  may send a NAS message (such as a Tracking Area Update Request, notification and/or other) to the MME  1405  of the eRemote UE  1401  (which may be referred to as a “source MME” for clarity). The message may include the indication that the access via layer 2 relay is to be enabled and/or an identifier (GUTI and/or other) of the eRelay UE  1402 . 
     As indicated by “ 4 ” in  FIG.  14   , based on the GUTI of the eRelay UE  1402 , the MME  1405  of the eRemote UE  1401  (the source MME) may know and/or determine the MME  1406  of the eRelay UE  1402  (which may be referred to as a “target MME” for clarity). The MME  1405  of the eRemote UE  1401  may send a Relay Authorization Check Request message to the MME  1406  of the eRelay UE  1402 . The message may include an identifier (such as an IMSI and/or other) of the eRemote UE  1401  and/or an identifier (such as a GUTI and/or other) of the eRelay UE  1402 . The MME  1406  of the eRelay UE  1402  may check whether the eRemote UE  1401  is permitted to access the network via the eRelay UE  1402  and may respond with a Relay Authorization Check Response message. The message may include an authorization result (such as whether the eRemote UE  1401  is permitted access to the network via the eRelay UE  1402 ) and/or an identifier of the eNB  1404  of the eRelay UE  1402 . 
     As indicated by “ 5 ” in  FIG.  14   , based on the response message received from the MME  1406  of the eRelay UE  1402 , the MME  1405  of the eRemote UE  1401  may check whether the eRemote UE  1401  and the eRelay UE  1402  are under the same eNB. If the MME  1405  of the eRemote UE  1401  knows and/or determines that the eRemote UE  1401  and the eRelay UE  1402  are under different eNBs, it may send a Path Switch Trigger message to the eNB  1403  that serves the eRemote UE  1401 . The message may include an indication of whether access via layer 2 relay is to be enabled and/or an identifier of the eNB  1404  that serves the eRelay UE  1402 . 
     As indicated by “ 6 ” in  FIG.  14   , based on the identifier of the eNB  1404  that serves the eRelay UE  1402 , the eNB  1403  may decide whether to perform and/or initiate a handover of the eRemote UE  1401  to the eNB  1404  that serves the eRelay UE  1402 . 
     As indicated in  FIG.  14   , one or more operations indicated by “ 7 ”-“ 16 ” may be performed. One or more of those operations may be similar to operations included in a 3GPP standard, although the scope of embodiments is not limited in this respect. 
     In some embodiments, an indication of access via layer 2 relay and an identifier (GUTI and/or other) of the eRelay UE  1402  may be included in the Handover Request message indicated by “ 10 ” in  FIG.  14   . In some embodiments, one or more operations of an RRC Connection Reconfiguration between the eNB  1404  and the eRelay UE  1402  may be performed. 
     As indicated by  1415  in  FIG.  14   , uplink data and/or downlink data may be exchanged between the eRemote UE  1401  and one or more components. This exchange may be performed in accordance with indirect communication, although the scope of embodiments is not limited in this respect. 
     Referring to  FIG.  15   , in the example scenario  1500 , the eRemote UE  1501  may switch from indirect communication (including but not limited to indirect 3GPP communication) to direct communication (including but not limited to direct 3GPP communication) under different eNBs. The switch may be S1 based, although the scope of embodiments is not limited in this respect. 
     As indicated by  1510  in  FIG.  15   , uplink data and/or downlink data may be exchanged between the eRemote UE  1501  and one or more components. This exchange may be performed in accordance with indirect communication, although the scope of embodiments is not limited in this respect. 
     As indicated by “ 1 ” in  FIG.  15   , the eRemote UE  1501  may send a NAS message (such as a TAU Request, Notification and/or other) to the MME  1505  of the eRemote UE  1501  (which may be referred to as a “source MME” for clarity). The message may include an indication that access via layer 2 relay is to be disabled. The message may include an indication a request that access via layer 2 relay be disabled. 
     As indicated by “ 2 ” in  FIG.  15   , the MME  1505  of the eRemote UE  1501  may send a Path Switch Trigger message to the eNB  1503 . The message may include an indication that the access via layer 2 relay is to be disabled. As indicated by “ 3 ” in  FIG.  15   , based on a measurement report of the eRemote UE  1501 , the eNB  1503  may decide whether to perform and/or initiate a handover of the eRemote UE  1501  to another eNB. 
     As indicated in  FIG.  15   , one or more operations indicated by “ 4 ”-“ 14 ” may be performed. One or more of those operations may be similar to operations included in a 3GPP standard, although the scope of embodiments is not limited in this respect. 
     In some embodiments, as indicated by “ 12 ” in  FIG.  15   , one or more operations related to RRC Connection Reconfiguration between the eNB  1503  and the eRelay UE  1502  may be performed. As indicated by “ 13 ” in  FIG.  15   , a PC5 Connection may be released. 
     As indicated by  1515  in  FIG.  15   , uplink data and/or downlink data may be exchanged between the eRemote UE  1501  and one or more components. This exchange may be performed in accordance with direct communication, although the scope of embodiments is not limited in this respect. 
     Referring to  FIG.  16   , in the example scenario  1600 , a handover of a plurality of eRemote UEs to another eNB together with an eRelay UE may be performed. The handover may be X2 based, although the scope of embodiments is not limited in this respect. One eRemote UE  1601  is shown in  FIG.  16   , but it is understood that multiple eRemote UEs may be used. For instance, multiple eRemote UEs may exchange uplink data and/or downlink data as shown in operations  1610  and  1615 . As indicated by  1610  in  FIG.  16   , uplink data and/or downlink data may be exchanged between the eRemote UE  1601  and one or more components. This exchange may be performed in accordance with indirect communication, although the scope of embodiments is not limited in this respect. 
     As indicated by “ 1 ” in  FIG.  16   , the eNB  1603  may decide to trigger a handover and/or relocation of the eRelay UE  1602 . In some embodiments, the handover and/or relocation may be performed via X2, although the scope of embodiments is not limited in this respect. 
     As indicated by “ 2 ” in  FIG.  16   , one or more operations may be performed. One or more of those operations may be similar to operations included in a 3GPP standard, although the scope of embodiments is not limited in this respect. In some embodiments, information (such as identifiers, information elements (IEs) and/or other) for multiple eRemote UEs  1601  and the eRelay UE  1602  may be included in one or more messages from source eNB  1603  to target eNB  1604 . 
     As indicated by  1615  in  FIG.  16   , uplink data and/or downlink data may be exchanged between the eRemote UE  1601  and one or more components. This exchange may be performed in accordance with indirect communication, although the scope of embodiments is not limited in this respect. 
     Referring to  FIG.  17   , in the example scenario  1700 , a handover of a plurality of eRemote UEs to another eNB together with an eRelay UE may be performed. The handover may be S1 based, although the scope of embodiments is not limited in this respect. One eRemote UE  1701  is shown in  FIG.  17   , but it is understood that multiple eRemote UEs may be used. For instance, multiple eRemote UEs may exchange uplink data and/or downlink data as shown in operations  1710  and  1715 . As indicated by  1710  in  FIG.  17   , uplink data and/or downlink data may be exchanged between the eRemote UE  1701  and one or more components. This exchange may be performed in accordance with indirect communication, although the scope of embodiments is not limited in this respect. 
     As indicated by “ 1 ” in  FIG.  17   , the source eNB  1703  may decide to trigger a relocation and/or handover of the eRelay UE  1702 . In some embodiments, the relocation and/or handover may be performed via S1, although the scope of embodiments is not limited in this respect. 
     One or more of the operations indicated by “ 2 ”-“ 10 ” in  FIG.  17    may be performed. One or more of those operations may be similar to operations included in a 3GPP standard, although the scope of embodiments is not limited in this respect. In some embodiments, information (such as identifiers, information elements (IEs) and/or other) for multiple eRemote UEs  1701  and the eRelay UE  1702  may be included in one or more messages exchanged in those operations. 
     As indicated by  1715  in  FIG.  17   , uplink data and/or downlink data may be exchanged between the eRemote UE  1701  and one or more components. This exchange may be performed in accordance with indirect communication, although the scope of embodiments is not limited in this respect. 
     In some embodiments, a path switch from indirect communication (including but not limited to indirect 3GPP communication) to direct communication (including but not limited to direct 3GPP communication) may be triggered by disablement of layer 2 relay operation by the eRelay UE  902 . When the layer 2 relay operation of the eRelay UE  902  is disabled by its serving MME  904  or by the eRelay UE  902  itself, the MME  904  of the eRelay UE  902  may send a Path Switch Trigger message to the eNB  903 . The eNB  903  may trigger the procedure to switch the eRemote UE  901  from indirect communication to direct communication. In some embodiments, the switch may use operations and/or techniques described regarding one or more of the figures, although the scope of embodiments is not limited in this respect. For instance, operations and/or techniques shown in one of  FIGS.  11 ,  13 ,  15    may be used, in some embodiments. 
     When the eRelay UE  902  disables the operation as a layer 2 relay, it may send a TAU message with an indication that the Layer 2 Relay has been disabled or is to be disabled. The serving MME  904  may send an S1-AP message to the eNB  903  to disable its layer 2 relay authorization. 
     In some embodiments, a cell reselection procedure may be used for the path switch from indirect communication (including but not limited to indirect 3GPP communication) to direct communication (including but not limited to direct 3GPP communication). In a non-limiting example (which may be similar to the flows shown in  FIGS.  13  and  15   ), when the source eNB  903  receives a Path Switch Trigger from an MME  904 , it may not necessarily initiate the handover procedure for the eRemote  901 . As an alternative, the source eNB  903  may send an RRC Release message with an indication of redirection to another eNB  903 . The message may be sent to the eRemote UE  901 . The eNB  903  may perform this operation based on a measurement report of the eRemote UE  901 . When the eRemote UE  901  receives the RRC Release message, it may reselect to the indicated eNB  903  and then may send a NAS message (such as a TAU, notification and/or other) to the target MME  904 . The message may include an indication of enablement of Layer 2 relay access. 
     In Example 1, an apparatus of an Evolved Node-B (eNB) may comprise memory. The apparatus may further comprise processing circuitry. The processing circuitry may be configured to decode, from a mobility management entity (MME), a path switch trigger message that indicates: an identifier of an eRelay UE for a relay arrangement for an Evolved Proximity-Based Services (ProSe) Remote User Equipment (UE). The processing circuitry may be further configured to determine, based on the identifier of the eRelay UE, whether the eRelay UE is served by the eNB or by another eNB. The processing circuitry may be further configured to, if it is determined that the eRelay UE is served by the eNB: encode, for transmission to the Evolved ProSe Remote UE, a radio resource control (RRC) connection reconfiguration message that indicates a switch from a direct communication to an indirect communication between the Evolved ProSe Remote UE and the eNB. The indirect communication may be through the eRelay UE in accordance with the relay arrangement. The memory may be configured to store the identifier of the eRelay UE. 
     In Example 2, the subject matter of Example 1, wherein the processing circuitry may be further configured to, if it is determined that the eRelay UE is served by another eNB: encode, for transmission to the Evolved ProSe Remote UE, a handover command message. The handover command message may indicate: a handover of the Evolved ProSe Remote UE to the other eNB, and an indirect communication between the Evolved ProSe Remote UE and the other eNB, the indirect communication through the eRelay UE in accordance with the relay arrangement. 
     In Example 3, the subject matter of one or any combination of Examples 1-2, wherein the RRC connection reconfiguration message is a first RRC connection reconfiguration message. The processing circuitry may be further configured to, if it is determined that the eRelay UE is served by the eNB: encode, for transmission to the eRelay UE, a second RRC connection reconfiguration message that indicates the switch from the direct communication to the indirect communication between the Evolved ProSe Remote UE and the eNB. 
     In Example 4, the subject matter of one or any combination of Examples 1-3, wherein the relay arrangement may be an Evolved ProSe UE-to-Network Relay. 
     In Example 5, the subject matter of one or any combination of Examples 1-4, wherein the identifier of the eRelay UE may be an eNB UE S1AP identifier. 
     In Example 6, the subject matter of one or any combination of Examples 1-5, wherein the processing circuitry may be further configured to decode, from the Evolved ProSe Remote UE, a measurement report received as part of the direct communication between the Evolved ProSe Remote UE and the eNB. The measurement report may indicate one or more signal quality measurements for the direct communication between the Evolved ProSe Remote UE and the eNB. The processing circuitry may be further configured to determine, based at least partly on the measurement report, whether to initiate a handover of the Evolved ProSe Remote UE to another eNB. 
     In Example 7, the subject matter of one or any combination of Examples 1-6, wherein the processing circuitry may be further configured to determine to initiate the handover if the signal quality measurement is less than a threshold. The processing circuitry may be further configured to determine to refrain from initiation of the handover if the signal quality measurement is greater than or equal to the threshold. 
     In Example 8, the subject matter of one or any combination of Examples 1-7, wherein the direct communication is a first direct communication, the path switch trigger message is a first path switch trigger message, and the RRC connection reconfiguration message is a first RRC connection reconfiguration message. The processing circuitry may be further configured to decode, from the MME, a second path switch trigger message that indicates that the indirect communication is to be disabled. The processing circuitry may be further configured to encode, for transmission to the Evolved ProSe Remote UE, a second RRC connection reconfiguration message to indicate a switch from the indirect communication to a second direct communication between the eNB and the Evolved ProSe Remote UE. 
     In Example 9, the subject matter of one or any combination of Examples 1-8, wherein the processing circuitry may be further configured to decode, from the Evolved ProSe Remote UE, a measurement report received as part of the indirect communication. The measurement report may indicate one or more signal quality measurements for the indirect communication. The processing circuitry may be further configured to determine, based at least partly on the measurement report, whether to initiate a handover of the Evolved ProSe Remote UE to another eNB for the second direct communication. 
     In Example 10, the subject matter of one or any combination of Examples 1-9, wherein the processing circuitry may be further configured to, as part of the relay arrangement: decode a downlink data packet received from a serving gateway (SGW) to be forwarded to the Evolved ProSe Remote UE; and encode the downlink data packet for transmission to the eRelay UE to be forwarded to the Evolved ProSe Remote UE. 
     In Example 11, the subject matter of one or any combination of Examples 1-10, wherein the apparatus may further include a transceiver to receive the uplink data packet. 
     In Example 12, the subject matter of one or any combination of Examples 1-11, wherein the processing circuitry may include a baseband processor to decode the uplink data packet. 
     In Example 13, a computer-readable storage medium may store instructions for execution by one or more processors to perform operations for communication by a User Equipment (UE). The UE may be configurable to operate as an eRelay UE. The operations may configure the one or more processors to decode an uplink data packet received from an eRemote UE in accordance with a relay arrangement in which the eRelay UE operates as a relay between an Evolved Node-B (eNB) and the eRemote UE. The eNB may operate in a Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) network. The operations may further configure the one or more processors to encode the uplink data packet for transmission to the eNB. The operations may further configure the one or more processors to decode, from the eNB, a control message that indicates a handover of the eRelay UE from the 3GPP LTE network to another network in accordance with a circuit switched fallback (CSFB) procedure or a single radio voice call continuity (SRVCC) procedure. The operations may further configure the one or more processors to, based on the handover from the 3GPP LTE network to the other network: encode, for transmission to the eRemote UE, a PC5 request message to indicate that the relay arrangement is to be disabled. 
     In Example 14, the subject matter of Example 13, wherein the operations may further configure the one or more processors to determine one or more signal quality measurements based on one or more downlink signals received from the eNB. The operations may further configure the one or more processors to determine, based on the signal quality measurements, whether an interruption of coverage by the 3GPP LTE network for the eRelay UE is expected to occur. The operations may further configure the one or more processors to, if it is determined that the interruption of coverage is expected to occur: encode, for transmission to the eRemote UE, the PC5 request message to indicate that the relay arrangement is to be disabled. 
     In Example 15, the subject matter of one or any combination of Examples 13-14, wherein the operations may further configure the one or more processors to determine that the interruption of coverage by the 3GPP LTE network for the eRelay UE is expected to occur if an average of the signal quality measurements is less than a threshold. 
     In Example 16, the subject matter of one or any combination of Examples 13-15, wherein the operations may further configure the one or more processors to determine a battery level of the eRelay UE. The operations may further configure the one or more processors to determine, based on the battery level, whether the relay arrangement is to be disabled. The operations may further configure the one or more processors to, if it is determined that the relay arrangement is to be disabled: encode, for transmission to the eRemote UE, the PC5 request message to indicate that the relay arrangement is to be disabled. 
     In Example 17, the subject matter of one or any combination of Examples 13-16, wherein the operations may further configure the one or more processors to determine that the relay arrangement is to be disabled if the battery level is less than a threshold. 
     In Example 18, the subject matter of one or any combination of Examples 13-17, wherein the other network may be a second generation (2G) network. 
     In Example 19, a User Equipment (UE) may be configurable to operate as an eRemote UE. An apparatus of the UE may comprise memory. The apparatus may further comprise processing circuitry. The processing circuitry may be configured to decode a downlink data packet received from an Evolved Node-B (eNB) as part of a direct communication between the eRemote UE and the eNB. The processing circuitry may be further configured to decode, from an eRelay UE, a PC5 connection message to establish a relay arrangement in which the eRelay UE is to operate as a relay. The processing circuitry may be further configured to encode, for transmission to an eRelay UE, an information request message that indicates an intention, of the eRemote UE, to communicate with the eRelay UE in accordance with the relay arrangement. The processing circuitry may be further configured to decode, from the eRelay UE, an information response message that indicates an identifier of the eRelay UE, wherein the memory is configured to store the identifier of the eRelay UE. The processing circuitry may be further configured to encode, for transmission to the eNB to be forwarded to a mobility management entity (MME), a tracking area update (TAU) message that indicates the intention, of the eRemote UE, to communicate with the eRelay UE in accordance with the relay arrangement. 
     In Example 20, the subject matter of Example 19, wherein the identifier of the eRemote UE may be a globally unique temporary identifier (GUTI). 
     In Example 21, the subject matter of one or any combination of Examples 19-20, wherein the processing circuitry may be further configured to encode the information request message for transmission to the eRelay UE as part of a sidelink communication. 
     In Example 22, the subject matter of one or any combination of Examples 19-21, wherein the relay arrangement may include a sidelink communication between the eRemote UE and the eRelay UE in accordance with a Proximity-Based Services (ProSe) arrangement. 
     In Example 23, the subject matter of one or any combination of Examples 19-22, wherein the processing circuitry may be further configured to determine a signal quality measurement for the direct communication based at least partly on a reception of the downlink data packet. The processing circuitry may be further configured to determine a signal quality measurement for the relay arrangement based at least partly on a reception of the PC5 connection message. The processing circuitry may be further configured to determine whether to communicate with the eRelay UE in accordance with the relay arrangement based at least partly on the signal quality measurement for the direct communication and the signal quality measurement for the relay arrangement. 
     In Example 24, the subject matter of one or any combination of Examples 19-23, wherein the eRemote UE may be configured to operate as an Evolved Proximity-Based Services (ProSe) Remote UE. The relay arrangement may be an Evolved ProSe UE-to-Network Relay. 
     In Example 25, a User Equipment (UE) may be configurable to operate as an eRelay UE. An apparatus of the UE may comprise means for decoding an uplink data packet received from an eRemote UE in accordance with a relay arrangement in which the eRelay UE operates as a relay between an Evolved Node-B (eNB) and the eRemote UE. The eNB may operate in a Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) network. The apparatus may further comprise means for encoding the uplink data packet for transmission to the eNB. The apparatus may further comprise means for decoding, from the eNB, a control message that indicates a handover of the eRelay UE from the 3GPP LTE network to another network in accordance with a circuit switched fallback (CSFB) procedure or a single radio voice call continuity (SRVCC) procedure. The apparatus may further comprise means for, based on the handover from the 3GPP LTE network to the other network: encoding, for transmission to the eRemote UE, a PC5 request message to indicate that the relay arrangement is to be disabled. 
     In Example 26, the subject matter of Example 25, wherein the apparatus may further comprise means for determining one or more signal quality measurements based on one or more downlink signals received from the eNB. The apparatus may further comprise means for determining, based on the signal quality measurements, whether an interruption of coverage by the 3GPP LTE network for the eRelay UE is expected to occur. The apparatus may further comprise means for, if it is determined that the interruption of coverage is expected to occur: encoding, for transmission to the eRemote UE, the PC5 request message to indicate that the relay arrangement is to be disabled. 
     In Example 27, the subject matter of one or any combination of Examples 25-26, wherein the apparatus may further comprise means for determining that the interruption of coverage by the 3GPP LTE network for the eRelay UE is expected to occur if an average of the signal quality measurements is less than a threshold. 
     In Example 28, the subject matter of one or any combination of Examples 25-27, wherein the apparatus may further comprise means for determining a battery level of the eRelay UE. The apparatus may further comprise means for determining, based on the battery level, whether the relay arrangement is to be disabled. The apparatus may further comprise means for, if it is determined that the relay arrangement is to be disabled: encoding, for transmission to the eRemote UE, the PC5 request message to indicate that the relay arrangement is to be disabled. 
     In Example 29, the subject matter of one or any combination of Examples 25-28, wherein the apparatus may further comprise means for determining that the relay arrangement is to be disabled if the battery level is less than a threshold. 
     In Example 30, the subject matter of one or any combination of Examples 25-29, wherein the other network may be a second generation (2G) network. 
     The Abstract is provided to comply with 37 C.F.R. Section 1.72(b) requiring an abstract that will allow the reader to ascertain the nature and gist of the technical disclosure. It is submitted with the understanding that it will not be used to limit or interpret the scope or meaning of the claims. The following claims are hereby incorporated into the detailed description, with each claim standing on its own as a separate embodiment.

Metadata:
Filing Date: 20180306
Publication Date: 20240723
Grant Date: 20240723
Priority Date: 20170310
Inventors: STOJANOVSKI, Alexandre Saso
SHAN, CHANGHONG
Assignee: APPLE INC
CPC Classifications: [{"code": "H04W36/30", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/0055", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/0022", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/302", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/00226", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W36/0064", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/033", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/00224", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W36/0064", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/00224", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W36/302", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/033", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/00226", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W88/04", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W36/03", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W4/50", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W36/30", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/0055", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/0022", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W36/03", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 68532451