Side link carrier for carrier aggregation

Abstract

The present disclosure relates to a method performed by a user equipment. The method involves determining a primary component carrier (PCC) for use in carrier aggregation over a sidelink interface with a second UE, wherein the component carrier is at least used for control signaling; and communicating with the second UE via the primary component carrier.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application No. 63 / 407,474, filed on September 16, 2022, entitled “Sidelink Carriers for Carrier Aggregation,” which is incorporated herein by reference in its entirety. Background Art

[0003] Wireless communication networks provide integrated communication platforms and telecommunication services to wireless user devices. Example telecommunication services include telephone, data (e.g., voice, audio and / or video data), messaging, Internet access and / or other services. Wireless communication networks have wireless access nodes that exchange wireless signals with wireless user devices using wireless network protocols (such as protocols described in various telecommunication standards promulgated by the Third Generation Partnership Project (3GPP)). Example wireless communication networks include time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal frequency division multiple access (OFDMA) networks, long term evolution (LTE) and fifth generation new radio (5G NR). Wireless communication networks use technologies such as OFDM, multiple input multiple output (MIMO), advanced channel coding, massive MIMO, beamforming and / or other features to facilitate mobile broadband services. Summary of the invention

[0004] The present disclosure describes sidelink carrier aggregation in a new generation wireless communication system (e.g., an NR system or a later generation system). In some specific implementations, a UE using a sidelink interface may be configured with a sidelink carrier aggregation configuration. The sidelink carrier aggregation configuration includes an indication of a sidelink primary component carrier (PCC) and one or more secondary component carriers (SCCs). The sidelink PCC acts as an anchor carrier that can be used to carry sidelink control signaling. One or more configured SCCs may be selectively activated and deactivated by the UE. Thus, a particular SCC may be used by the UE only if the SCC is activated (and may no longer be used if the SCC is deactivated). In addition to other benefits, the selective activation of the SCC enables the UE to save power by enabling the UE to monitor only the activated SCC.

[0005] According to one aspect of the present disclosure, a method performed by a first user equipment (UE) is disclosed. The method involves determining a primary component carrier (PCC) used in carrier aggregation through a sidelink interface with a second UE, wherein the PCC is used at least for control signaling; and communicating with the second UE via the PCC.

[0006] The specific implementations described previously can be adapted to use a computer-implemented method; a non-transitory computer-readable medium storing computer-readable instructions to perform the computer-implemented method; and a computer system comprising a computer memory interoperably coupled to a hardware processor configured to perform the computer-implemented method or instructions stored on the non-transitory computer-readable medium. These and other embodiments can optionally include one or more of the following features.

[0007] In some implementations, the method further involves receiving, from a base station, a sidelink carrier aggregation configuration including an indication of the PCC.

[0008] In some implementations, the sidelink carrier aggregation configuration also includes a configured set of component carriers.

[0009] In some implementations, communicating with the second UE via the PCC involves initiating a capability exchange procedure with the second UE to determine that the second UE is capable of sidelink carrier aggregation.

[0010] In some specific implementations, the method also involves generating a candidate secondary component carrier (SCC) set, the SCC set including one or more SCCs selected from the configured component carrier set for use in a sidelink interface between the second UE; and sending a reconfiguration message including the candidate SCC set to the second UE.

[0011] In some implementations, sending the reconfiguration message to the second UE involves sending the reconfiguration message to the second UE via the PCC.

[0012] In some implementations, the method further involves receiving a response message from the second UE accepting or rejecting the candidate SCC set.

[0013] In some implementations, the response message rejects the candidate SCC set, and the response message further includes a reason for the rejection.

[0014] In some specific implementations, the candidate SCC is a first candidate SCC set and the reconfiguration message is a first reconfiguration message, and the method further involves: receiving a second reconfiguration message including a second candidate SCC set from a second UE; and determining whether to process the first candidate SCC set or the second candidate SCC set.

[0015] In some implementations, determining whether to process the first candidate SCC set or the second candidate SCC set is based on a comparison of a first source ID of the first UE and a second source ID of the second UE.

[0016] In some implementations, determining whether to process the first set of candidate SCCs or the second set of candidate SCCs is based on comparing: (i) a first tiebreaker value included in the first reconfiguration message and (ii) a second tiebreaker value included in the second reconfiguration message.

[0017] In some implementations, the first tiebreaker value and the second tiebreaker value are based on randomly selected numbers or timestamps.

[0018] In some specific implementations, the method further involves sending a response message accepting the second candidate SCC set to the second UE in response to determining to process the second candidate SCC set.

[0019] In some specific implementations, the method further involves receiving a response message accepting the first candidate SCC set from the second UE in response to determining to process the first candidate SCC set.

[0020] In some specific implementations, the method further involves generating an SCC message for activating or deactivating a first SCC in the candidate SCC set; and sending the SCC message to the second UE.

[0021] In some implementations, the generating of the SCC message is performed in response to determining that the first UE is a primary UE and the second UE is a secondary UE.

[0022] In some specific implementations, the method further involves starting a timer after sending the SCC message to the second UE; receiving a response from the second UE within a preconfigured timer period; and stopping the timer in response to receiving the response.

[0023] In some implementations, the SCC message also includes a tiebreaker value.

[0024] The details of one or more specific implementations of the subject matter in this specification are set forth in the detailed description, the drawings, and the claims. Other features, aspects, and advantages of the subject matter will become apparent from the description, the claims, and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 An example communication system including sidelink communications according to some implementations is shown.

[0026] Figure 2 An example messaging flow for sidelink secondary component carrier (SCC) configuration between two user equipments (UEs) is shown in accordance with some implementations.

[0027] Figure 3 Another example messaging flow for sidelink SCC configuration between two UEs according to some implementations is shown.

[0028] Figure 4 An example sidelink MAC CE for activating or deactivating an SCC is shown according to some implementations.

[0029] Figure 5A An example sidelink SCC activation / deactivation MAC CE request format is shown according to some specific implementations.

[0030] Figure 5B An example sidelink SCC activation / deactivation MAC CE response format is shown according to some implementations.

[0031] Figure 6 Example methods according to some implementations are shown.

[0032] Figure 7 A user equipment (UE) according to some implementations is shown.

[0033] Figure 8 An access node according to some implementations is shown.

[0034] Like reference numbers and designations in the various drawings indicate like elements. DETAILED DESCRIPTION

[0035] One of the areas of research and development in Release 18 of the 3rd Generation Partnership Project (3GPP) technical standards is sidelink carrier aggregation in New Radio (NR) systems. Conventional carrier aggregation techniques may have deficiencies relative to carrier aggregation for sidelink operations in NR systems. Therefore, there is a need to develop a sidelink carrier aggregation process for NR.

[0036] The present disclosure describes sidelink carrier aggregation in a new generation wireless communication system (e.g., an NR system or a later generation system). In some specific implementations, a UE using a sidelink interface may be configured with a sidelink carrier aggregation configuration. The sidelink carrier aggregation configuration includes an indication of a sidelink primary component carrier (PCC) and one or more secondary component carriers (SCCs). The sidelink PCC acts as an anchor carrier that can be used to carry sidelink control signaling. One or more configured SCCs may be selectively activated and deactivated by the UE. Thus, a particular SCC may be used by the UE only if the SCC is activated (and may no longer be used if the SCC is deactivated). In addition to other benefits, the selective activation of the SCC enables the UE to save power by enabling the UE to monitor only the activated SCC.

[0037] Figure 1 An example communication system 100 including sidelink communication according to some implementations is illustrated. Note that Figure 1The system is just one example of a possible system, and features of the present disclosure may be implemented in other wireless communication systems.

[0038] The following description is provided for an example communication system operating in conjunction with a fifth generation (5G) network provided by the 3GPP technical specifications. However, the example implementation is not limited in this regard, and the described examples may be applied to other networks that may benefit from the principles described herein, such as 3GPP Long Term Evolution (LTE) networks, Wi-Fi networks, and the like. In addition, other types of communication standards are also possible, including future 3GPP systems (e.g., sixth generation (6G)), IEEE 802.16 protocols (e.g., WMAN, WiMAX, etc.), and the like. Although various aspects may be described herein using terms typically associated with 5G NR, various aspects of the present disclosure may be applied to other systems, such as 4G and / or systems after 5G (e.g., 6G).

[0039] As shown, the communication system 100 includes a plurality of user equipments. More specifically, the communication system 100 includes two UEs 105 (UE 105-1 and UE 105-2 are collectively referred to as "UE 105" or "UEs 105"), two base stations 110 (base stations 110-1 and base stations 110-2 are collectively referred to as "base stations 110" or "base stations 110"), two cells 115 (cells 115-1 and cells 115-2 are collectively referred to as "cells 115" or "cells 115"), and one or more servers 135 in a core network (CN) 140 connected to the Internet 145.

[0040] In some implementations, UE 105 may communicate directly with base station 110 via links 120 (links 120-1 and 120-2 are collectively referred to as "a link 120" or "links 120"), which utilize a direct interface with the base station (referred to as a "Uu interface"). Each of links 120 may represent one or more channels. Links 120 are illustrated as air interfaces that implement communication coupling and may conform to cellular communication protocols, such as 3GPP LTE protocols, advanced long term evolution (LTE-A) protocols, LTE-based unlicensed spectrum access (LTE-U), 5G protocols, NR protocols, NR-based unlicensed spectrum access (NR-U) protocols, and / or any other communication protocols discussed herein.

[0041] As shown, some user equipments may be able to communicate directly with each other, for example, without intermediate infrastructure equipment (such as base station 110-1). In this example, UE 105-1 may communicate directly with UE 105-2. Similarly, UE 105-2 may communicate directly with UE 105-1. This peer-to-peer communication may utilize a "side link" interface such as a PC5 interface. In some specific implementations, the PC5 interface supports direct cellular communication between user equipments (e.g., between UE 105), while the Uu interface supports cellular communication with infrastructure equipment (such as a base station). For example, UE 105 may use the PC5 interface for radio resource control (RRC) signaling exchange (also referred to as PC5-RRC signaling) between UEs. The PC5 / Uu interface is used only as an example, and PC5 as used herein may represent various other possible wireless communication technologies that allow direct side link communication between user equipments, while Uu may represent cellular communication performed between user equipments and infrastructure equipment (such as a base station).

[0042] In order to transmit / receive data to / from one or more base stations 110 or UE 105, UE 105 may include a transmitter / receiver (or alternatively, a transceiver), a memory, one or more processors, and / or other similar components that enable UE 105 to operate according to one or more wireless communication protocols and / or one or more cellular communication protocols. UE 105 may have multiple antenna elements that enable UE 105 to maintain multiple links 120 and / or side links 125 to transmit / receive data to / from multiple base stations 110 and / or multiple UEs 105. For example, as Figure 1 As shown, UE 105 - 1 may be connected to base station 110 - 1 via link 120 and simultaneously connected to UE 105 - 2 via side link 125 .

[0043] In some implementations, one or more sidelink radio bearers (SL-RBs) may be established on the sidelink 125. The sidelink radio bearers may include signaling radio bearers (SL-SRBs) and / or data radio bearers (SL-DRBs). The signaling radio bearers may be of different types, including SL-SRB0, SL-SRB1, SL-SRB2, SL-SRB3, and SL-SRB4.

[0044] The PC5 interface may alternatively be referred to as a sidelink interface and may include one or more logical channels, including but not limited to a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), a physical sidelink discovery channel (PSDCH), a physical sidelink broadcast channel (PSBCH), a physical sidelink feedback channel (PSFCH) and / or any other similar communication channel. The PSFCH carries feedback related to the success or failure reception of the sidelink transmission. The PSSCH may be scheduled by the sidelink control information (SCI) carried in the sidelink PSCCH. In some examples, the sidelink interface may operate on an unlicensed spectrum (e.g., in an unlicensed 5 GHz (GHz) and 6 GHz band) or a (licensed) shared spectrum.

[0045] In one example, the sidelink interface implements vehicle-to-everything (V2X) communications. V2X communications may, for example, follow the 3GPP cellular V2X (C-V2X) specification, or follow one or more other or subsequent standards, whereby vehicles and other devices and network entities may communicate. V2X communications may utilize both long-range (e.g., cellular) communications and short-range to medium-range (e.g., non-cellular) communications. V2X communications with cellular capabilities may be referred to as cellular V2X (C-V2X) communications. C-V2X systems may use various cellular radio access technologies (RATs), such as 4G LTE or 5G NR RAT (or RATs after 5G, e.g., 6G RAT). Certain LTE standards available in V2X systems may be referred to as LTE-Vehicle (LTE-V) standards. As used herein in the context of a V2X system, and as defined above, the term "user equipment" may generally refer to a device associated with a mobile participant or traffic participant in a V2X system, for example, a mobile (capable of moving) communication device such as a vehicle, a pedestrian user equipment (PUE) device, and a roadside unit (RSU).

[0046] In some implementations, the UEs 105 may be physical hardware devices capable of running one or more applications, accessing network services via one or more radio links 120 with corresponding base stations 110 (also referred to as “serving” base stations), and communicating with each other via side links 125. The links 120 may allow the UEs 105 to send and receive data from the base stations 110 providing the links 120. The side links 125 may allow the UEs 105 to send and receive data with each other. The side links 125 between the UEs 105 may include one or more channels for transmitting information from the UE 105-1 to the UE 105-2 (or vice versa) and / or between the UE 105 and a UE-type RSU (or vice versa).

[0047] In some implementations, base stations 110 can communicate with each other over a backhaul connection 130, and can communicate with one or more servers 135 within CN 140 over another backhaul connection 133. The backhaul connection can be a wired and / or wireless connection.

[0048] In some implementations, UE 105 is configured to use a resource pool for sidelink communications. The sidelink resource pool may be divided into multiple time slots, frequency channels, and frequency subchannels. In some examples, UE 105 is synchronized and performs sidelink transmissions aligned with time slot boundaries. It may be desirable for the UE to select several time slots and subchannels for transmission of a transport block. In some examples, the UE may use different subchannels to transmit a transport block across multiple time slots within its own resource selection window.

[0049] In some implementations, the base station 110 may configure a special exception resource pool for the UE 105. The special exception resource pool includes resources that the UE 105 can use in special exception situations such as radio link failure (RLF). The special exception resource pool may include resources selected based on random resource allocation.

[0050] In some implementations, the communication system 100 supports different broadcast types, including unicast, broadcast, and groupcast (or multicast) communications. Unicast refers to direct communication between two UEs. Broadcast refers to communication broadcasted by a single UE to multiple other UEs. Groupcast refers to communication transmitted from a single UE to a set of UEs that meet a certain condition (e.g., as members of a specific group).

[0051] In some implementations, the UE 105 is configured to use sidelink carrier aggregation in the sidelink 125. In one example, the UE 105 can receive a sidelink carrier aggregation configuration from a base station (e.g., base station 110), possibly via an RRC message over Uu (e.g., link 120). The sidelink carrier aggregation configuration can include a set of component carriers to be used for carrier aggregation services in broadcast / multicast and / or unicast. By providing the set of component carriers, the base station can have control over carrier usage in the sidelink 125.

[0052] In some specific implementations, the sidelink carrier aggregation configuration also includes a PCC / SCC configuration that specifies a PCC and a set of one or more SCCs. This can be explicitly indicated by marking one of these carriers as the primary carrier in the sidelink carrier configuration. Alternatively, this can be implicitly indicated by assuming that the first carrier in the carrier set list / array is the primary carrier. Unlike CA over the Uu interface (where the UL CA configuration and the DL CA configuration are different), the PCC / SCC configuration used in the sidelink can be bidirectional, which means that the configuration is used in both directions of the sidelink communication between the UE 105. Thus, there is no explicit need for a unidirectional configuration for each direction of SL communication between two UEs 105. However, without losing generality, the method disclosed herein also covers the case where different SCC sets are used in different directions between UEs 105. In some examples, the UE 105 uses the PCC / SCC configuration in the sidelink unicast. Specifically, when operating in the sidelink unicast, the UE 105 uses the PCC as the primary carrier and uses a set or a subset of the SCC as a secondary carrier. As explained in more detail below, the specific set of SCCs used by UE 105 may be reconfigured by UE 105, possibly using PC5-RRC signaling. Thus, the set of SCCs ultimately used by UE 105 may not be identical to the set included in the sidelink carrier aggregation configuration.

[0053] In some specific implementations, the PCC can be used to carry one or more types of information between UEs 105. First, the PCC can be used to carry PC5-RRC messages, such as messages for initial and / or basic configuration of the side link 125. Second, the PCC can be used to carry PC5 signaling protocol stack (PC5-S) messages, such as direct communication request (DCR) messages, which can be used to drive the establishment of PC5 links in upper layers (e.g., V2X layer, ProSe layer, etc.). Third, the PCC can be used to carry synchronization signals, such as side link synchronization signals (SLSS) and side link synchronization signal blocks (S-SSB). Fourth, the PCC can be used for cross-carrier side link scheduling. Fifth, the PCC can be used to carry side link medium access control (MAC) control elements (CEs), such as side link MAC CEs for activating / deactivating SCCs, which will be described in more detail below. Note that the PCC may also be used to carry only some PC5-RRC messages, rather than all PC5-RRC messages. For example, after a capability exchange between two SL UEs, via the RRCReconfigurationSidelink procedure, the two UEs may negotiate to move the ensuing RRC signaling in SL-SRB3 to use both PCC and SCC, thereby obtaining the throughput / reliability benefits of SL carrier aggregation. This may also apply to some PC5-S signaling in SL-SRB2.

[0054] Sixth, the PCC can be used to carry hybrid automatic repeat request (HARQ) feedback because HARQ feedback does not need to be sent in each component carrier. There are at least two reasons why the PCC can be used to carry HARQ feedback. One reason is that sending sidelink HARQ feedback via the PCC can be advantageous in many scenarios, such as when the peer UE receiving the feedback has power / radio frequency (RF) chain limitations, or when the PCC is on a lower frequency with better propagation than other component carriers. Second, the resource pool on the SCC can be configured to have no PSFCH resources.

[0055] In some implementations, the activated SCC may be used to carry: user plane data, HARQ feedback, sidelink channel state information (CSI) reports, SCC-specific configurations (if such configurations are supported), and / or PC5-RRC for SLSS.

[0056] In some implementations, the UE 105 may reconfigure a set of SCCs, add a set of SCCs, or remove an SCC from a set of SCCs, possibly using PC5-RRC signaling. More specifically, after the UE 105 receives the sidelink carrier aggregation configuration, the UE communicates to determine the sidelink carrier aggregation capabilities of the other UE. After each UE determines the capabilities of the other UE, one of the UEs 105 may initiate an SCC set configuration process. The initiating UE generates a new set of candidate SCCs and provides the candidate set to the peer UE. Once the peer UE receives the candidate SCC set, the peer UE determines whether to accept or reject the new set, and provides a response message to the initiating UE indicating whether the new set is accepted or rejected. If the response message is a rejection message, the message may include a reason or cause for the rejection. As an example, the reason for the rejection may be that the UE cannot follow the request, which means that the capabilities of the UE do not support the use of the SCC set provided by the initiating UE. As another example, the reason for the rejection may be a rejection of the proposed SCC set. Here, the capabilities of the peer UE may support the configuration, but the peer UE has an alternative proposal and determines to select the alternative configuration. Furthermore, the peer UE may know that one of the component carriers in the proposed SCC set has poor performance (e.g., due to poor radio conditions), and may therefore determine to select a different CC instead.

[0057] Note that this process is different from Uu, as there is no master node in the sidelink communication. Therefore, it is possible for the UE to reject the candidate SCC set of the peer UE, while in Uu, the UE cannot reject the network's selection of the candidate component carrier list.

[0058] Figure 2 An example messaging flow 200 for sidelink SCC configuration between two UEs according to some implementations is shown. The messaging flow 200 may be used for reconfiguration, addition, and / or removal of a sidelink SCC, which operations may use PC5-RRC signaling. In this example, two UEs, UE 1 and UE 2 (also labeled as UE 220A, UE 220B) are coupled via a sidelink interface.

[0059] At 202, UE 220A, UE 220B exchange sidelink capability information. The sidelink capability information includes information that implicitly or explicitly indicates whether the UE supports sidelink carrier aggregation. As an example, the indication can be part of the SL capability signaling IE, which can include: (i) an IE named "SL-carrierAggregation-r18", which explicitly indicates whether the UE supports CA, or (ii) a CA bandwidth category parameter included in "supportBandCombination-SL", which implicitly indicates that the UE supports sidelink carrier aggregation.

[0060] After each UE determines the sidelink carrier aggregation capabilities of the other UE, one of the UEs may initiate configuration of a candidate SCC set. At 204, UE 220A determines to initiate configuration of a candidate SCC set. UE 220A then checks the configured carrier aggregation carriers (e.g., included in the sidelink carrier aggregation configuration) and selects one or more SCC candidates to be included in the candidate SCC set, which operations may be based on one or more factors. In some examples, the UE may select a candidate SCC set based on the SL CA capabilities of the two UEs (e.g., which SL CA carriers are supported), how many CCs are required for the traffic throughput, measurements associated with the CCs, and / or corresponding QoS requirements to be supported in the sidelink.

[0061] At 206, UE 220A sends a message (e.g., RRC reconfiguration sidelink) including a candidate SCC set to UE 220B. At 208, UE 220B sends an acceptance message (e.g., RRC reconfiguration sidelink complete) to UE 220B to accept the candidate set or sends a rejection message (e.g., RRC reconfiguration sidelink failed) to reject the candidate set. In some specific implementations, once the SCC set is determined, the RRC reconfiguration sidelink process can also be used to further determine whether to use carrier aggregation for one or more SL-RBs. And if carrier aggregation is used, which carriers in the SCC set are selected for CA between the two UEs, and the selection may be made on the SL-RB based on the SL-RB. For example, for SL-SRBs used to carry PC5-S or PC5-RRC signaling, the PCC and SCC combination is also feasible for improving the throughput and reliability of the control plane process in the sidelink interface. The initiating UE of the RRC reconfiguration sidelink message may propose to supplement the SL-SRB "x" with one or more additional selected SCCs, and the responding UE may confirm the configuration by sending an RRCReconfigurationCompleteSidelink message. The additional SCCs for the SL-SRB may be selected based on specific criteria (e.g., based on CBR (channel busy rate)) (e.g., from the configured carrier aggregation carriers or from a set of SCCs).

[0062] In some scenarios, before the sidelink SCC configuration process initiated by one UE is completed, it is possible that the same process can be initiated by another UE. If the SCC set is configured as bidirectional, this may cause a conflict. When two UEs initiate the sidelink SCC configuration process at the same time, a conflict may occur. In order to avoid such conflicts, UE 105 can be configured with a mechanism for determining which process should be processed and which process should be abandoned. In one example, the mechanism is based on which UE's source layer 2 ID (SRC L2 ID) is greater than (or less than) the SRC L2 ID of another UE. This mechanism favors one UE so that the selection of which UE's process to keep is static. In another example, the mechanism is based on a dynamically selected "tie-breaker" included in the sidelink reconfiguration message. The tie-breaker can be based on a randomly selected number or a timestamp associated with the sidelink reconfiguration message.

[0063] Figure 3 Another example messaging flow 300 for sidelink SCC configuration between two UEs according to some implementations is shown. The example messaging flow 300 shows a scenario where UE 320A, UE 320B simultaneously initiates a sidelink SCC configuration procedure.

[0064] At 302, UE 320A and UE 320B exchange sidelink capability information. The sidelink capability information includes information indicating whether the UE supports sidelink carrier aggregation. After each UE determines the sidelink carrier aggregation capability of the other UE, at least one of the UEs may initiate configuration of a candidate set of SCCs. In this example, both UEs determine to initiate configuration of a candidate set of SCCs. Figure 3 As shown, at 304A, 304B, both UEs check the configured carrier aggregation carriers and select one or more SCC candidates.

[0065] At 306A, UE 320A sends a message (e.g., RRC reconfiguration sidelink) to UE 320B including a candidate SCC set selected by UE 320A. The message also includes a first tiebreaker value (e.g., a randomly selected number or a timestamp). At 306B, UE 320B also sends a message to UE 320A including a candidate SCC set selected by UE 320B. The message also includes a second tiebreaker value (e.g., a randomly selected number or a timestamp). Once each UE receives the message from the other UE, UE 320A and UE 320B determine that a conflict has occurred and responsively execute a mechanism for determining which candidate SCC set is selected and which candidate SCC set is abandoned. In this example, the mechanism is a dynamic mechanism. Therefore, UE 320A and UE 320B compare the first tiebreaker value with the second tiebreaker value at 308A, 308B, respectively. When the first tiebreaker value "wins", the first candidate SCC set generated by UE 320A will be processed by UE 320B, and when the second tiebreaker value "wins", the second candidate SCC set generated by UE 320B will be processed by UE 320A. In this example, the UE determines to select the first candidate SCC set generated by UE 320A based on the comparison. Therefore, at 310, UE 320B sends an accept message (e.g., RRC Reconfiguration Sidelink Complete) to UE 320A.

[0066] In some implementations, the RRC signaling for configuring the SCC may also be used to activate the SCC by default as an initial condition. That is, completion of the configuration of the SCC set also places one or more SCCs in the set in the "ACTIVE" state. Therefore, the UE does not need to send another explicit signaling to activate those CCs in the SCC set.

[0067] After the SCC set is selected, one or more of the UEs 105 can be configured to selectively activate or deactivate the SCC. In some implementations, the UE 105 can be configured to use one of the one or more procedures for activating / deactivating the SCC.

[0068] In the first process, the UE may use the sidelink MAC CE to activate or deactivate the SCC. In an example, the MAC CE may include 8 bits, and thus up to 8 sidelink SCCs may be activated / deactivated using a single MAC CE. Each bit C i Corresponding to the index in the SCC set: "0" means that the SCC at this index is deactivated; "1" means that the SCC at this index is activated.

[0069] Figure 4 An example sidelink MAC CE 400 for activating or deactivating an SCC according to some implementations is shown. Figure 4 As shown in , MAC CE 400 includes 8 bits, so a single MAC CE can be used to activate / deactivate up to 8 sidelink SCCs. Each bit Ci corresponds to an index in the SCC set: "0" means that the SCC at the index is deactivated; "1" means that the SCC at the index is activated.

[0070] Note that if the SCC set is for directional use only (e.g., TX UE to RX UE), only the TX UE can send activation / deactivation signaling to the peer UE (RX UE), and there will be no conflict in this case. However, for the case where the SCC set is bidirectional, if both UEs can issue sidelink MAC CE commands to the other UE, a conflict may occur. That is, in the case of a bidirectional SCC, the two UEs may issue activation and / or deactivation commands that may cause a conflict.

[0071] In some implementations, a "master" UE is selected so that only one of the UEs is allowed to activate / deactivate the SCC. In these implementations, only the "master" UE can issue a sidelink MAC CE command. The "master-slave" relationship can be determined based on predetermined rules. In a first example, the master UE is the UE that initiates the SCC carrier configuration during the PC5-RRC process. In a second example, the master UE is the UE that initiates the PC5-S "direct communication request" message during the link establishment process or the UE that initiates the capability exchange process in the PC5-RRC protocol. In a third example, the master UE is the UE with a larger L2Src ID (or alternatively a UE with a lower L2Src ID).

[0072] In a fourth example, the master UE is the UE with more stringent performance requirements. The performance requirements may be determined based on the traffic load of the UE or the QoS requirements of the traffic. As an example, consider a scenario where a UE (UE A) has more traffic that needs to be delivered to UE B than traffic that needs to be delivered from UE B to UE A. In this scenario, UE A has more stringent performance requirements. In another example, if the reliability of UE-A's traffic is 99.99%, but the reliability requirement of UE-B's traffic is only 99%, UE A has more stringent performance requirements. In a fifth example, the master UE is selected based on a priority value for inter-UE coordination information, where the priority value may be set based on a set of conditions.

[0073] In some implementations, the primary role can be "shared" between peer UEs. For example, "time sharing" can be implemented so that each UE can alternately assume the primary role, which operation may be based on a pre-configured cycle. The cycle length can be configured in Uu RRC or PC5-RRC.

[0074] In the second process, SCC activation / deactivation is based on a request-response negotiation between the two UEs. In this process, the first UE sends a MAC CE "SCC activation / deactivation request" to the second UE and starts a timer. The second UE is configured to return a confirmation / rejection MAC CE in response within a pre-configured timer period. The first UE is configured not to trigger a new request as long as the timer is running, and is configured to stop the timer if a response is received. In this way, the two UEs can still share the decision-making process without introducing a "master / slave" role between the two UEs. In some examples, a "decisive condition" can be included in the "SCC activation / deactivation request" to resolve conflicts in scenarios where both UEs send "SCC activation / deactivation requests".

[0075] Figure 5A An example sidelink SCC activation / deactivation MAC CE request format 500 is shown according to some implementations. Figure 5A As shown in FIG. 5 , MAC CE 500 includes 8 bits, so a single MAC CE can be used to activate / deactivate up to 8 sidelink SCCs. Each bit Ci corresponds to an index in the SCC set: "0" means that the SCC at that index is deactivated; "1" means that the SCC at that index is activated. As also shown in FIG. 5 , MAC CE 500 can include up to 8 bits for the "tiebreaker" value.

[0076] Figure 5B An example sidelink SCC activation / deactivation MAC CE response format 520 is shown according to some implementations. Figure 5BAs shown in , MAC CE 520 may include one or more bits indicating whether MAC CE 520 accepts or rejects the message. In the scenario where the C / R bit indicates rejection, MAC CE 520 may additionally include one or more bits for a "Reject Reason" code.

[0077] In some implementations, the UE 105 may be configured to perform maintenance of the SCC. Different component carriers may experience similar path loss conditions between two sidelink UEs, but the sidelink channel may be shared by many sidelink UEs in close proximity to each other, so there may be fluctuations in radio conditions in different carriers. Therefore, in some implementations, per-CC measurement reporting is supported in sidelink carrier aggregation. In these implementations, a measurement object (MO) structure may be generated for one or more carriers to enable per-CC measurements.

[0078] The measurement on the CC will evaluate the signal quality of a specific component carrier (CC) among the set of CCs used in the side link, and the evaluation may be performed by comparing the measured value with a pre-configured threshold. The SCC measurement can be based on a measurement threshold or report (for example, a channel busy rate [CBR] or a sidelink reference signal received power [RSRP]). For an active SCC, the measurement can be performed based on the SL-RSRP. For a deactivated SCC, the measurement can be performed for the CBR. In some embodiments, the measurement or measurement report can be event triggered. For example, the triggering event can be whether the signal quality is below a threshold. In this example, an event-triggered measurement report is sent to a peer UE. The report enables the peer UE to determine which CCs (if any) to activate or deactivate.

[0079] Figure 6 600 according to some specific implementations. For clarity of presentation, the following description generally describes the method 600 in the context of other figures in this specification. For example, the method 600 can be performed by Figure 1 UE 105. It should be understood that method 600 can be performed by any suitable system, environment, software, hardware or a combination of systems, environments, software and hardware as appropriate. In some specific implementations, the steps of method 600 can be run in parallel, in combination, in a loop or in any order. In some specific implementations, method 600 is performed by the first UE.

[0080] At 602, method 600 involves determining a primary component carrier (PCC) for use in carrier aggregation over a sidelink interface with a second UE, wherein the PCC is used for at least control signaling.

[0081] At 604, method 600 involves communicating with a second UE via a primary component carrier.

[0082] In some implementations, the method further involves receiving, from a base station, a sidelink carrier aggregation configuration including an indication of the PCC.

[0083] In some implementations, the sidelink carrier aggregation configuration also includes a configured set of component carriers.

[0084] In some implementations, communicating with the second UE via the PCC involves initiating a capability exchange procedure with the second UE to determine that the second UE is capable of sidelink carrier aggregation.

[0085] In some specific implementations, the method also involves generating a candidate secondary component carrier (SCC) set, the SCC set including one or more SCCs selected from the configured component carrier set for use in a sidelink interface between the second UE; and sending a reconfiguration message including the candidate SCC set to the second UE.

[0086] In some implementations, sending the reconfiguration message to the second UE involves sending the reconfiguration message to the second UE via the PCC.

[0087] In some implementations, the method further involves receiving a response message from the second UE accepting or rejecting the candidate SCC set.

[0088] In some implementations, the response message rejects the candidate SCC set, and the response message further includes a reason for the rejection.

[0089] In some specific implementations, the candidate SCC is a first candidate SCC set and the reconfiguration message is a first reconfiguration message, and the method further involves: receiving a second reconfiguration message including a second candidate SCC set from a second UE; and determining whether to process the first candidate SCC set or the second candidate SCC set.

[0090] In some implementations, determining whether to process the first candidate SCC set or the second candidate SCC set is based on a comparison of a first source ID of the first UE and a second source ID of the second UE.

[0091] In some implementations, determining whether to process the first set of candidate SCCs or the second set of candidate SCCs is based on comparing: (i) a first tiebreaker value included in the first reconfiguration message and (ii) a second tiebreaker value included in the second reconfiguration message.

[0092] In some implementations, the first tiebreaker value and the second tiebreaker value are based on randomly selected numbers or timestamps.

[0093] In some specific implementations, the method further involves sending a response message accepting the second candidate SCC set to the second UE in response to determining to process the second candidate SCC set.

[0094] In some specific implementations, the method further involves receiving a response message accepting the first candidate SCC set from the second UE in response to determining to process the first candidate SCC set.

[0095] In some specific implementations, the method further involves generating an SCC message for activating or deactivating a first SCC in the candidate SCC set; and sending the SCC message to the second UE.

[0096] In some implementations, the generating of the SCC message is performed in response to determining that the first UE is a primary UE and the second UE is a secondary UE.

[0097] In some specific implementations, the method further involves starting a timer after sending the SCC message to the second UE; receiving a response from the second UE within a preconfigured timer period; and stopping the timer in response to receiving the response.

[0098] In some implementations, the SCC message also includes a tiebreaker value.

[0099] Figure 7 UE 700 according to some implementations is shown. UE 700 may be used with Figure 1 UE 105 is similar to and substantially interchangeable therewith.

[0100] UE 700 can be any mobile or non-mobile computing device, such as a mobile phone, a computer, a tablet, an industrial wireless sensor (e.g., a microphone, a pressure sensor, a thermometer, a motion sensor, an accelerometer, an inventory sensor, a voltage / current meter, etc.), a video device (e.g., a camera, a camcorder, etc.), a wearable device (e.g., a smart watch), or a loose IoT device.

[0101] UE 700 may include a processor 702, an RF interface circuit 704, a memory / storage device 706, a user interface 708, a sensor 710, a driver circuit 712, a power management integrated circuit (PMIC) 714, one or more antennas 716, and a battery 718. The components of UE 700 may be implemented as an integrated circuit (IC), a portion of an integrated circuit, a discrete electronic device or other module, logic component, hardware, software, firmware, or a combination thereof. Figure 7 The block diagram of UE 700 is intended to show a high-level view of some of the components of UE 700. However, some of the components shown may be omitted, additional components may be present, and different arrangements of the components shown may occur in other implementations.

[0102] Components of UE 700 may be coupled to various other components via one or more interconnects 720, which may represent any type of interface, input / output, bus (local, system, or extension), transmission line, trace, optical connection, etc., which allows various circuit components (on a common or different chip or chipset) to interact with each other.

[0103] The processor 702 may include processor circuits such as a baseband processor circuit (BB) 722A, a central processor unit circuit (CPU) 722B, and a graphics processor unit circuit (GPU) 722C. The processor 702 may include any type of circuit or processor circuit that executes or otherwise operates computer-executable instructions (such as program codes, software modules, or functional processes from the memory / storage device 706) to cause the UE 700 to perform operations as described herein.

[0104] In some implementations, the baseband processor circuit 722A may access a communication protocol stack 724 in the memory / storage device 706 to communicate over a 3GPP compatible network. Generally speaking, the baseband processor circuit 722A may access a communication protocol stack to: perform user plane functions at the physical (PHY) layer, the medium access control (MAC) layer, the radio link control (RLC) layer, the packet data convergence protocol (PDCP) layer, the service data adaptation protocol (SDAP) layer, and the PDU layer; and perform control plane functions at the PHY layer, the MAC layer, the RLC layer, the PDCP layer, the RRC layer, and the non-access layer. In some implementations, the PHY layer operations may be additionally / alternatively performed by components of the RF interface circuit 704. The baseband processor circuit 722A may generate or process a baseband signal or waveform that carries information in a 3GPP compatible network. In some implementations, the waveform used for NR can be based on cyclic prefix orthogonal frequency division multiplexing (OFDM) "CP-OFDM" in uplink or downlink, and discrete Fourier transform spread OFDM "DFT-S-OFDM" in uplink.

[0105] The memory / storage device 706 may include one or more non-transitory computer-readable media, which include instructions (e.g., communication protocol stack 724) that can be executed by one or more processors in the processor 702 to enable the UE 700 to perform various operations described herein. The memory / storage device 706 includes any type of volatile or non-volatile memory that can be distributed throughout the UE 700. In some specific implementations, some of the memory / storage devices 706 may be located on the processor 702 itself (e.g., L1 cache and L2 cache), while other memory / storage devices 706 are located outside the processor 702, but can be accessed via a memory interface. The memory / storage device 706 may include any suitable volatile or non-volatile memory, such as, but not limited to, dynamic random access memory (DRAM), static random access memory (SRAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state memory, or any other type of memory device technology.

[0106] The RF interface circuit 704 may include a transceiver circuit and a radio frequency front end module (RFEM), which allows the UE 700 to communicate with other devices through a radio access network. The RF interface circuit 704 may include various elements arranged in a transmit path or a receive path. These elements may include, for example, switches, mixers, amplifiers, filters, synthesizer circuits, control circuits, etc.

[0107] In the receive path, the RFEM may receive the radiated signal from the air interface via one or more antennas 716 and continue to filter and amplify the signal (using a low noise amplifier). The signal may be provided to a receiver of the transceiver, which down-converts the RF signal to a baseband signal provided to a baseband processor of the processor 702.

[0108] In the transmit path, the transmitter of the transceiver up-converts the baseband signal received from the baseband processor and provides the RF signal to the RFEM. The RFEM may amplify the RF signal through a power amplifier before the signal is radiated across the air interface via the antenna 716. In various specific implementations, the RF interface circuit 704 may be configured to transmit / receive signals in a manner compatible with NR access technology.

[0109] Antenna 716 may include antenna elements to convert electrical signals into radio waves to travel through the air and convert received radio waves into electrical signals. These antenna elements may be arranged into one or more antenna panels. Antenna 716 may have an antenna panel that is omnidirectional, directional, or a combination thereof to achieve beamforming and multiple input / multiple output communications. Antenna 716 may include a microstrip antenna, a printed antenna manufactured on the surface of one or more printed circuit boards, a patch antenna, a phased array antenna, etc. Antenna 716 may have one or more panels that are designed for a specific frequency band including a band in FR1 or FR2.

[0110] The user interface 708 includes various input / output (I / O) devices designed to enable a user to interact with the UE 700. The user interface 708 includes input device circuits and output device circuits. The input device circuit includes any physical or virtual components for accepting input, including in particular one or more physical or virtual buttons (e.g., a reset button), a physical keyboard, a keypad, a mouse, a touchpad, a touch screen, a microphone, a scanner, or a headset, etc. The output device circuit includes any physical or virtual components for displaying information or otherwise delivering information (such as sensor readings, actuator positions, or other similar information). The output device circuit may include any number or combination of audio or visual displays, including in particular one or more simple visual outputs / indicators (e.g., binary state indicators, such as light emitting diodes "LEDs") and multi-character visual outputs, or more complex outputs, such as display devices or touch screens (e.g., liquid crystal displays "LCDs", LED displays, quantum dot displays, projectors, etc.), where the output of characters, graphics, multimedia objects, etc. is generated or produced by the operation of the UE 700.

[0111] Sensor 710 may include a device, module, or subsystem that is intended to detect events or changes in its environment and to communicate information about the detected events (sensor data) to some other device, module, subsystem, etc. Examples of such sensors include, among others: an inertial measurement unit including an accelerometer, gyroscope, or magnetometer; a microelectromechanical system or nanoelectromechanical system including a three-axis accelerometer, three-axis gyroscope, or magnetometer; a fluid level sensor; a temperature sensor (e.g., a thermistor); a pressure sensor; an image capture device (e.g., a camera or a lensless aperture); a light detection and ranging sensor; a proximity sensor (e.g., an infrared radiation detector, etc.); a depth sensor; an ambient light sensor; an ultrasonic transceiver; a microphone or other similar audio capture device; and the like.

[0112] The driver circuit 712 may include software elements and hardware elements for controlling specific devices embedded in the UE 700, attached to the UE 700, or otherwise communicatively coupled to the UE 700. The driver circuit 712 may include separate drivers to allow other components to interact with or control various input / output (I / O) devices that may be present in the UE 700 or connected to the UE. For example, the driver circuit 712 may include: a display driver for controlling and allowing access to a display device, a touch screen driver for controlling and allowing access to a touch screen interface, a sensor driver for obtaining sensor readings of the sensor 710 and controlling and allowing access to the sensor 710, a driver for obtaining an actuator position of an electromechanical component or controlling and allowing access to an electromechanical component, a camera driver for controlling and allowing access to an embedded image capture device, and an audio driver for controlling and allowing access to one or more audio devices.

[0113] The PMIC 714 may manage power provided to various components of the UE 700. Specifically, with respect to the processor 702, the PMIC 714 may control power source selection, voltage scaling, battery charging, or DC-DC conversion.

[0114] In some implementations, the PMIC 714 may control or otherwise be part of various power saving mechanisms of the UE 700. The battery 718 may power the UE 700, but in some examples, the UE 700 may be mounted in a fixed location and may have a power source coupled to a power grid. The battery 718 may be a lithium-ion battery, a metal-air battery such as a zinc-air battery, an aluminum-air battery, a lithium-air battery, etc. In some implementations, such as in vehicle-based applications, the battery 718 may be a typical lead-acid automotive battery.

[0115] Figure 8 An access node 800 (e.g., a base station or gNB) is shown according to some implementations. The access node 800 may be associated with Figure 1 Access node 800 may include a processor 802 , an RF interface circuit 804 , a core network (CN) interface circuit 806 , a memory / storage device circuit 808 , and one or more antennas 810 .

[0116] The components of the access node 800 may be coupled to various other components via one or more interconnects 812. The processor 802, RF interface circuitry 804, memory / storage circuitry 808 (including a communication protocol stack 814), one or more antennas 810, and the interconnect 812 may be coupled to the reference Figure 7Elements shown and described with like nomenclature are similar.For example, processor 802 may include processor circuits such as baseband processor circuits (BB) 816A, central processor unit circuits (CPU) 816B, and graphics processor unit circuits (GPU) 816C.

[0117] The CN interface circuit 806 may provide connectivity to a core network (e.g., a 5GC using a 5th Generation Core Network (5GC) compatible network interface protocol such as a Carrier Ethernet protocol or some other suitable protocol). Network connectivity may be provided to / from the access node 800 via optical fiber or wireless backhaul. The CN interface circuit 806 may include one or more dedicated processors or FPGAs for communicating using one or more of the aforementioned protocols. In some implementations, the CN interface circuit 806 may include multiple controllers for providing connectivity to other networks using the same or different protocols.

[0118] As used herein, the terms "access node", "access point", etc. may be described as equipment that provides radio baseband functionality for data and / or voice connections between a network and one or more users. These access nodes may be referred to as BS, gNB, RAN node, eNB, NodeB, RSU, TRxP or TRP, etc., and may include ground stations (e.g., terrestrial access points) or satellite stations that provide coverage within a geographic area (e.g., a cell). As used herein, the terms "NG RAN node", etc. may refer to an access node 800 (e.g., a gNB) operating in an NR or 5G system, and the terms "E-UTRAN node", etc. may refer to an access node 800 (e.g., an eNB) operating in an LTE or 4G system. According to various specific implementations, the access node 800 may be implemented as one or more of a dedicated physical device such as a macrocell base station and / or a low power (LP) base station for providing a femtocell, picocell or other similar cell with a smaller coverage area, smaller user capacity or higher bandwidth than a macrocell.

[0119] In some implementations, all or part of the access node 800 may be implemented as one or more software entities running on a server computer as part of a virtual network that may be referred to as a CRAN and / or a virtual baseband unit pool (vBBUP). In a V2X scenario, the access node 800 may be or act as a "road side unit". The term "road side unit" or "RSU" may refer to any traffic infrastructure entity used for V2X communication. The RSU may be implemented in or by a suitable RAN node or a stationed (or relatively stationed) UE, wherein an RSU implemented in or by a UE may be referred to as a "UE-type RSU", an RSU implemented in or by an eNB may be referred to as an "eNB-type RSU", an RSU implemented in or by a gNB may be referred to as a "gNB-type RSU", and so on.

[0120] For ease of description, various components may be described as performing one or more tasks. Such descriptions should be interpreted as including the phrase "configured to". Representing a component configured to perform one or more tasks expressly intends that the component does not invoke the interpretation of 35 U.S.C. §112(f).

[0121] For one or more embodiments, at least one of the components shown in one or more of the foregoing figures may be configured to perform one or more operations, techniques, processes, or methods described in the following example section. For example, the baseband circuit described above in conjunction with one or more of the foregoing figures may be configured to operate according to one or more of the examples described below. For another example, the circuits associated with the UE, base station, network element, etc. described above in conjunction with one or more of the foregoing figures may be configured to operate according to one or more of the examples described below in the example section.

[0122] Example

[0123] Embodiment 1 includes one or more processors of a first user equipment (UE), the one or more processors being configured to cause the first UE to perform operations including: determining a primary component carrier (PCC) used in carrier aggregation via a sidelink interface with a second UE, wherein the PCC is used at least for control signaling; and communicating with the second UE via the primary component carrier.

[0124] Embodiment 2 is one or more processors according to embodiment 1, the operations further comprising: receiving a sidelink carrier aggregation configuration including an indication of a PCC from a base station.

[0125] Embodiment 3 is one or more processors according to embodiment 2, wherein the sidelink carrier aggregation configuration further includes a configured set of component carriers.

[0126] Embodiment 4 is one or more processors according to any of embodiments 1-3, wherein communicating with the second UE via the PCC involves initiating a capability exchange procedure with the second UE to determine that the second UE is capable of sidelink carrier aggregation.

[0127] Embodiment 5 is one or more processors according to any of embodiments 1-4, wherein the operations also include: generating a candidate secondary component carrier (SCC) set, the SCC set including one or more SCCs selected from a configured component carrier set for use in a side link interface with a second UE; and sending a reconfiguration message including the candidate SCC set to the second UE.

[0128] Embodiment 6 is one or more processors according to embodiment 5, wherein sending the reconfiguration message to the second UE includes sending the reconfiguration message to the second UE via the PCC.

[0129] Embodiment 7 is one or more processors according to embodiment 5, wherein the operations further include: receiving a response message from the second UE to accept or reject the candidate SCC set.

[0130] Embodiment 8 is one or more processors according to embodiment 7, wherein the response message rejects the candidate SCC set, and wherein the response message further includes a rejection reason.

[0131] Embodiment 9 is one or more processors according to embodiment 5, wherein the candidate SCC is a first candidate SCC set and the reconfiguration message is a first reconfiguration message, and wherein the operations further include: receiving a second reconfiguration message including a second candidate SCC set from a second UE; and determining whether to process the first candidate SCC set or the second candidate SCC set.

[0132] Embodiment 10 is one or more processors according to embodiment 9, wherein determining whether to process the first set of candidate SCCs or the second set of candidate SCCs is based on a comparison of a first source ID of the first UE and a second source ID of the second UE.

[0133] Embodiment 11 is one or more processors according to embodiment 9, wherein determining whether to process the first candidate SCC set or the second candidate SCC set is based on a comparison of: (i) a first tiebreaker value included in the first reconfiguration message and (ii) a second tiebreaker value included in the second reconfiguration message.

[0134] Embodiment 12 is one or more processors of embodiment 11, wherein the first tiebreaker value and the second tiebreaker value are based on randomly selected numbers or timestamps.

[0135] Embodiment 13 is one or more processors according to embodiment 9, wherein the operations further include: in response to determining to process the second candidate SCC set, sending a response message to the second UE to accept the second candidate SCC set.

[0136] Embodiment 14 is one or more processors according to embodiment 9, the operations further comprising: in response to determining to process the first candidate SCC set, receiving a response message accepting the first candidate SCC set from the second UE.

[0137] Embodiment 15 is one or more processors according to embodiment 5, the operations further comprising: generating an SCC message for activating or deactivating a first SCC in the candidate SCC set; and sending the SCC message to a second UE.

[0138] Embodiment 16 is the one or more processors of embodiment 15, wherein the generating of the SCC message is performed in response to determining that the first UE is a primary UE and the second UE is a secondary UE.

[0139] Embodiment 17 is one or more processors according to embodiment 15, wherein the operations further include: starting a timer after sending the SCC message to the second UE; receiving a response from the second UE within a preconfigured timer period; and stopping the timer in response to receiving the response.

[0140] Embodiment 18 is one or more processors according to embodiment 15, wherein the SCC message further includes a tiebreaker value.

[0141] Embodiment 19 is one or more processors according to embodiment 5, wherein the operations further include: specifying at least one SCC for carrier aggregation in a specific sidelink signaling radio bearer (SL-SRB) from a candidate SCC set; and including an indication of the specific SL-SRB in a reconfiguration message.

[0142] Embodiment 20 may include a non-transitory computer storage medium encoded with instructions that, when executed by one or more computers, cause the one or more computers to perform operations according to any of Embodiments 1 to 19.

[0143] Embodiment 21 may include a system comprising one or more computers and one or more storage devices, on which are stored operable instructions that, when executed by the one or more computers, cause the one or more computers to perform operations according to any of embodiments 1 to 19.

[0144] Embodiment 22 may include a method for performing operations according to any of embodiments 1 to 19.

[0145] Embodiment 23 may include a device comprising logic components, modules or circuits for performing one or more elements of the operations described in or related to the operations described in any of embodiments 1 to 19 or any other operations or processes described herein.

[0146] Embodiment 24 may include methods, techniques or processes described in or related to the operations described in any of embodiments 1 to 19, or parts or portions thereof.

[0147] Embodiment 25 may include a device, such as user equipment, comprising: one or more processors and one or more computer-readable media, the one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform methods, techniques, or processes, or portions thereof, described in or related to the operations described in any of embodiments 1 to 19.

[0148] Embodiment 26 may include a computer program including instructions, wherein execution of the program by a processing element causes the processing element to perform a method, technique, or process, or a portion thereof, described in or related to the operation described in any of Embodiments 1 to 19. The operations or actions performed by the instructions executed by the processing element may include the operations described in any of Embodiments 1 to 19.

[0149] Embodiment 27 may include a method of communicating in a wireless network as shown and described herein.

[0150] Embodiment 28 may include a system for providing wireless communication as shown and described herein. The operations or actions performed by the system may include operations according to any one of embodiments 1 to 19.

[0151] Embodiment 29 may include an apparatus for providing wireless communication as shown and described herein. The operations or actions performed by the apparatus may include operations according to any one of embodiments 1 to 19.

[0152] The operations previously described according to embodiments 1 to 19 can be implemented using a computer-implemented method; a non-transitory computer-readable medium storing computer-readable instructions to execute the computer-implemented method; and a computer system comprising a computer memory interoperably coupled to a hardware processor, the hardware processor being configured to execute the computer-implemented method or instructions stored on the non-transitory computer-readable medium.

[0153] Unless explicitly stated otherwise, any of the above embodiments may be combined with any other embodiment (or combination of embodiments). The foregoing description of one or more specific implementations provides illustration and description, but is not intended to be exhaustive or to limit the scope of the embodiments to the precise form disclosed. Modifications and variations are possible in view of the above teachings or may be obtained from the practice of various embodiments.

[0154] Although the above embodiments have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to include all such variations and modifications.

[0155] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to users.

Claims

1. One or more processors of a first user equipment (UE), the one or more processors configured to cause the first UE to perform operations, the operations comprising: determining a primary component carrier (PCC) for use in carrier aggregation over a sidelink interface with a second UE, wherein the PCC is used for at least control signaling; as well as Communicate with the second UE via the primary component carrier.

2. The one or more processors of claim 1, the operations further comprising: A sidelink carrier aggregation configuration including an indication of the PCC is received from a base station.

3. The one or more processors of claim 2, wherein the sidelink carrier aggregation configuration further comprises a configured set of component carriers.

4. The one or more processors of any one of claims 1 to 3, wherein communicating with the second UE via the PCC involves initiating a capability exchange procedure with the second UE to determine that the second UE is capable of sidelink carrier aggregation.

5. The one or more processors of any one of claims 1 to 4, the operations further comprising: generating a candidate secondary component carrier (SCC) set, the candidate SCC set comprising one or more SCCs selected from a configured set of component carriers for use in the sidelink interface with the second UE; as well as and sending a reconfiguration message including the candidate SCC set to the second UE.

6. The one or more processors of claim 5, wherein sending the reconfiguration message to the second UE comprises sending the reconfiguration message to the second UE via the PCC.

7. The one or more processors of claim 5, the operations further comprising: A response message accepting or rejecting the candidate SCC set is received from the second UE.

8. The one or more processors of claim 7, wherein the response message rejects the set of candidate SCCs, and wherein the response message further includes a rejection reason.

9. The one or more processors of claim 5, wherein the candidate SCC is a first set of candidate SCCs and the reconfiguration message is a first reconfiguration message, and the operations further comprise: receiving, from the second UE, a second reconfiguration message including a second candidate SCC set; as well as Determine whether to process the first set of candidate SCCs or the second set of candidate SCCs.

10. The one or more processors of claim 9, wherein determining whether to process the first set of candidate SCCs or to process the second set of candidate SCCs is based on a comparison of a first source ID of the first UE and a second source ID of the second UE.

11. The one or more processors of claim 9, wherein determining whether to process the first set of candidate SCCs or to process the second set of candidate SCCs is based on a comparison of: (i) a first tiebreaker value included in the first reconfiguration message and (ii) a second tiebreaker value included in the second reconfiguration message.

12. The one or more processors of claim 11, wherein the first tiebreaker value and the second tiebreaker value are based on randomly selected numbers or timestamps.

13. The one or more processors of claim 9, the operations further comprising: In response to determining to process the second candidate SCC set, sending a response message accepting the second candidate SCC set to the second UE.

14. The one or more processors of claim 9, the operations further comprising: In response to determining to process the first candidate SCC set, receiving a response message accepting the first candidate SCC set from the second UE.

15. The one or more processors of claim 5, the operations further comprising: generating an SCC message for activating or deactivating a first SCC in the candidate SCC set; as well as sending the SCC message to the second UE.

16. The one or more processors of claim 15, wherein the generating of the SCC message is performed in response to determining that the first UE is a primary UE and the second UE is a secondary UE.

17. The one or more processors of claim 15, the operations further comprising: starting a timer after sending the SCC message to the second UE; receiving a response from the second UE within a preconfigured timer period; as well as The timer is stopped in response to receiving the response.

18. The one or more processors of claim 15, wherein the SCC message further comprises a tiebreaker value.

19. The one or more processors of claim 5, the operations further comprising: designating at least one SCC from the set of candidate SCCs for the carrier aggregation in a specific sidelink signaling radio bearer (SL-SRB); as well as An indication of the specific SL-SRB is included in the reconfiguration message.

20. A non-transitory computer storage medium encoded with instructions that, when executed by one or more computers, cause the one or more computers to perform the operations of any one of claims 1 to 19.

21. A method of performing the operations of any one of claims 1 to 19.

22. User equipment comprising one or more processors according to any one of claims 1 to 19.

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