Patent Publication Number: US-2023164745-A1

Title: Inter-user equipment (ue) coordination information for new radio (nr) sidelink communication

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims priority to U.S. Provisional Patent Application No. 63/298,062, which was filed Jan. 10, 2022; and U.S. Provisional Patent Application No. 63/298,153, which was filed Jan. 10, 2022; the disclosures of which are hereby incorporated by reference. 
    
    
     FIELD 
     Various embodiments generally may relate to the field of wireless communications. For example, some embodiments may relate to inter-user equipment (UE) coordination information for new radio (NR) sidelink communication. 
     BACKGROUND 
     New radio (NR) Vehicle-to-anything (V2X) sidelink communication is a synchronous communication system with distributed resource allocation. User equipments (UEs) autonomously select resources for sidelink transmission based on predefined sensing and resource selection procedures implemented by transmit (TX) UEs. The sensing and resource selection procedures are designed to reduce potential sidelink conflicts in transmissions or resource reservations (e.g., collisions or half-duplex conflicts). Given that sensing and resource selection procedures are executed only by TX UEs and do not consider the environment at the receiver side there is non-negligible probability of sidelink conflicts (collisions). To address this problem, the inter-UE coordination feedback from RX UEs can be used to improve resource allocation decisions by TX UEs and improve overall reliability of NR-V2X sidelink communication. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments will be readily understood by the following detailed description in conjunction with the accompanying drawings. To facilitate this description, like reference numerals designate like structural elements. Embodiments are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings. 
         FIG.  1    illustrates Stage-2 sidelink control information (SCI) and medium access control-control element (MAC-CE) preparation timelines, in accordance with various embodiments. 
         FIG.  2    illustrates Stage-2 SCI and MAC-CE processing timelines, in accordance with various embodiments. 
         FIG.  3    schematically illustrates a wireless network in accordance with various embodiments. 
         FIG.  4    schematically illustrates components of a wireless network in accordance with various embodiments. 
         FIG.  5    is a block diagram illustrating components, according to some example embodiments, able to read instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium) and perform any one or more of the methodologies discussed herein. 
         FIG.  6    depicts an example procedure for practicing the various embodiments discussed herein. 
     
    
    
     DETAILED DESCRIPTION 
     The following detailed description refers to the accompanying drawings. The same reference numbers may be used in different drawings to identify the same or similar elements. In the following description, for purposes of explanation and not limitation, specific details are set forth such as particular structures, architectures, interfaces, techniques, etc. in order to provide a thorough understanding of the various aspects of various embodiments. However, it will be apparent to those skilled in the art having the benefit of the present disclosure that the various aspects of the various embodiments may be practiced in other examples that depart from these specific details. In certain instances, descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description of the various embodiments with unnecessary detail. For the purposes of the present document, the phrases “A or B” and “A/B” mean (A), (B), or (A and B). 
     Various embodiments herein provide techniques for sending and receiving inter-user equipment (UE) coordination information for sidelink communication. The inter-UE coordination information may be provided via sidelink control information (SCI) and/or medium access control-control element (MAC-CE). Aspects regarding resource reservation and/or indication for UE coordination information are described. Additionally, new SCI formats for inter-UE coordination information are provided. 
     New radio (NR) Vehicle-to-anything (V2X) sidelink communication is a synchronous communication system with distributed resource allocation. UEs autonomously select resources for sidelink transmission based on predefined sensing and resource selection procedures implemented by transmit (TX) UEs. The sensing and resource selection procedures are designed to reduce potential sidelink conflicts in transmissions or resource reservations (e.g., collisions or half-duplex conflicts). Given that sensing and resource selection procedures are executed only by TX UEs and do not consider the environment at the receiver side there is non-negligible probability of sidelink conflicts (collisions). To address this problem, the inter-UE coordination feedback from RX UEs can be used to improve resource allocation decisions by TX UEs and improve overall reliability of NR-V2X sidelink communication. 
     Inter-UE coordination solutions are being designed for NR V2X sidelink communication as a part of the third generation partnership project (3GPP) Release-17 (Rel. 17) work item on sidelink enhancements. Two high level inter-UE coordination solutions have been identified in 3GPP to improve NR V2X sidelink performance:
         Inter-UE coordination scheme #1 (sidelink conflict/collision avoidance)
           This scheme aims to utilize inter-UE coordination feedback to avoid half-duplex and collisions problems for NR V2X communication. The basic principle behind this solution is that a UE providing inter-UE coordination feedback will report preferred and/or non-preferred sets of resources to surrounding sidelink transmitters. Sidelink transmitters will apply TX based sensing procedures and use received inter-UE coordination feedback to select/reserve sidelink resources for transmission and avoid potential sidelink communication conflicts.   
           Inter-UE coordination scheme #2 (sidelink conflict resolution)
           This scheme aims to utilize inter-UE coordination feedback to resolve sidelink conflicts that either already occurred or potential future conflicts that were detected based on resource reservation signaling. The idea behind this approach is to inform sidelink transmitters about detected sidelink conflicts through inter-UE coordination feedback, so that TX UEs can either perform additional retransmission, or drop planned transmission and reselect resource for transmission or continue transmission on reserved resource.   
               

     It was agreed that the M triplets/combinations of the time resource indication value (TRIV), frequency resource indication value (FRIV) and Preserved according to the 3GPP Release-16 (Rel.16) definition are transmitted. For the range of values of M less or equal to 3 this information can be transmitted in the second stage sidelink control information (SCI). This leaves a lot of open signaling details as well as the SCI formats that are described herein. 
     Specifically, embodiments herein relate to first and second stage SCI information to enable transmission of preferred or non-preferred resource sets in the second stage SCI. It also describes related fields to resource signaling irrespective of the information container. Embodiments herein may the use of inter-UE coordination for resource allocation for Rel. 17 sidelink (SL). Specific embodiments may relate to one or more of the 3GPP technical specifications (TSs) 38,212, 38.213, 38.214, and 38.331. 
     2 nd  Stage SCI Formats Indication for Inter-UE Coordination 
     After decoding the 1 st  stage SCI all necessary information to decode the 2 nd  stage SCI needs to be available. As the current 2 nd  stage SCI formats do not include the resource information for inter-UE coordination this means at least one additional 2 nd  stage SCI format needs to be defined. However, now there are different 2 nd  stage SCI formats fulfilling different communication needs. Thus, we see two solution to the 2 nd  stage SCI format indication: 
     Two or more different 2 nd  stage SCI formats are indicated in the 1 st  stage SCI Only one additional 2 nd  stage SCI format is indicated in the 1 st  stage SCI. The presence of different 2 nd  stage SCI fields is conditional on sub-format indication in the 2 nd  stage SCI information itself. 
     For sensing purposes, it may is still be important that even devices that do not implement inter-UE coordination can at least decode the 1 st  stage SCI information and at most demodulate and decode PSSCH. In Rel.16, there are 2 different SCI formats defined in the 1st stage SCI field “2nd-stage SCI format”. As this bit field is 2 bits long there are 2 additional reserved entries available. In addition, up to 4 reserved bits for the 1st stage SCI can be configured per resource pool. 
     If separate feedback signaling is defined for the preferred set, the non-preferred set and the non-preferred set with half duplex resources, the following signaling options can be considered in Table 1. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Resource set options. 
               
            
           
           
               
               
               
               
            
               
                   
                 Preferred 
                   
                   
               
               
                   
                 resource set 
                 Non-preferred 
                 Non-preferred 
               
               
                   
                 (1-A-1 or 1-A-1 + 
                 resource set 
                 half duplex set 
               
               
                   
                 1-A-2) 
                 (1-B-1) 
                 (1-B-2) 
               
               
                   
                   
               
            
           
           
               
               
               
               
            
               
                 Option 1 
                 X 
                 X 
                 X 
               
               
                 Option 2 
                 X 
                   
                 X 
               
               
                 Option 3 
                   
                 X 
                 X 
               
               
                 Option 4 
                 X 
                 X 
               
               
                 Option 5 
                 X 
               
               
                 Option 6 
                   
                 X 
               
               
                   
               
            
           
         
       
     
     Combining the number of options for inter-UE coordination signaling will also enabling both current 2 nd  stage SCI formats (A and B) means that we would need to signal up to 12 2 nd  SCI formats. Large amount of new 2 nd  stage SCI formats designed for inter-UE coordination feedback is not justified and alternative solutions with minimum number of new stage-2 SCI formats should be pursued. 
     Indication of the 2 nd  Stage SCI Formats in the 1 st  Stage SCI: 
     Full 2 nd  stage SCI format indication in the 1st stage SCI can be signaled via multiple ways as briefly described/introduced in the next paragraph&#39;s. 
     All used combinations of current 2nd stage SCI formats and inter-UE coordination set options are defined as a separate 2 nd  stage format. The configuration can be dependent on:
         Inter-UE coordination information   Resource pool configuration       

     Via this configuration or via limiting the number of defined/supported it is possible to limit the number of the 2 nd  stage formats. 
     It is also possible to add inter-UE coordination information to the Rel.16 2 nd  stage SCI formats. Which resource sets are signaled in the SCI can be separately indicated via an additional field in the 1 st  stage SCI. For example, SCI format 2-C would be SCI format 2-A with inter-UE coordination. Also, in this case it is possible to restrict the option for resource sets to be signaled via the following configuration
         Inter-UE coordination information   Resource pool configuration       

     Indication of the 2 nd  Stage Inter-UE Coordination Formats in the 2 nd  Stage SCI 
     In this case the selection which information is contained in the inter-UE coordination is dependent on fields in the 2nd stage SCI. This means some new 2nd stage SCI formats are created and all additional information of which inter-UE coordination format is present is contained in the second stage SCI. An example would be that two additional 2nd stage SCI formats 2-C and 2-D are created. These would represent format 2-A and 2-B with inter-UE coordination feedback. Which resource sets are present in the 2nd stage SCI is then indicated in the 2nd stage SCI itself. In another embodiment, only one new SCI format can be introduced for the purpose of inter-UE coordination feedback e.g., SCI format 2-C. In this case, the 2nd stage SCI should also indicate whether fields of SCI format 2-A and 2-B are used together with inter-UE coordination format. 
     Depending on signaling design, actual size of the 2nd stage SCI can be different. The maximum number of the 2nd stage SCI bits need to be known a priori (e.g., before channel coding as at the receiver, as it is not possible to know which option is taken before the channel decoding). If for given indication option, the actual 2 nd  stage SCI size is smaller than the predefined maximum, then dummy bits need be inserted to align with maximum size (e.g., size-matching need to be performed). 
     Indication of 2 nd  Stage Format the Number of Resources in the 1 st  Stage 
     In this case there would be 2 additional formats indicated in the 1 st  SCI. These would present the Rel.16 formats with inter-UE coordination feedback. In addition, the reserved bits available in the 1 st  stage SCI would be used to indicate the number of resources that are signaled in the 2 nd  stage SCI. This has the advantage that the sized for the bits in the 2 nd  stage SCI does not always need to use the maximum number of bits as number of signaled triplets is known after the 1 st  stage SCI. 
     Inter-UE Coordination Resource Indication 
     N triplets of TRIV, FRIV and Preserve should be used. However, the Rel-16 1st stage SCI version of the FRIV does not contain information of the first frequency allocation as in its original purpose this was already known. As in the original signaling the value of “sl-MaxNumPerReserve” also needs to be known. For Rel-16 1st stage SCI this value is configured as part of the resource pool configuration and represents the number of resource that are signaled per TRIV and FRIV. Also, the first slots are not indicated for the TRIV in Rel-16 1st stage SCI as the current slot is known. All options for these additional parameters as well as overhead saving options when multiple sets are signaled need to be discussed. It is also clear that to calculate the SCI size the maximum number of bits out of all supported/configured options need to be used as which option is actually taken is unknown before channel decoding, but the number of bits that need to be decoded needs to be known a priori. Note that different signaling option for each value can be chosen for the case of SCI or medium access control (MAC) control element (CE) signaling of these values. 
     Signaling of sl-MaxNumPerReserve: 
     In principle it would be possible to have a different value for each of the signaled resources. This would enable the full flexibility of signaling resources, but also result in a large overhead. The following options illustrate the different ways to enable UE A and UE B to have the same understanding of the value used:
         sl-MaxNumPerReserve is pre-configured: The pre-configuration would be contained in the resource pool. Potentially this configuration is different for different resource sets.   sl-MaxNumPerReserve is signaled per triplet of TRIV, FRIV and Preserve. In this case the used value is explicitly signaled.   sl-MaxNumPerReserve is contained in the coordination request information   sl-MaxNumPerReserve is configured by the network   sl-MaxNumPerReserve is negotiated during unicast- or groupcast connection setup       

     Signaling of the Number of Resources N in a Resource Set: 
     The following list illustrates all options for this case. Please note that different options could be chose for the signaling in the SCI and MAC CE based signaling:
         N is fixed (Field size 0 as no dynamic signaling): In this case the value that is used for inter-UE coordination can be determined based on one of following options:
           Pre-configured   Configured by the network   Send during the inter-UE coordination request   Negotiated during unicast- or groupcast connection setup   
           N is dynamically signaled (Field size ┌log 2  N max −N min ┐): In this case N is explicitly signaled. A value from N max  to N min  need to be defined as otherwise the required field size is unknown. The value range be defined dependent on the following options:   Pre-configured   Configured by the network   Send during the inter-UE coordination request   Negotiated during unicast- or groupcast connection setup       

     Signaling of the Starting Slot: 
     As in the original definition of the TRIV the current slot is defined as the starting slot it is necessary to signal the starting slot for inter-UE coordination. A different form of signaling can be used if some slot information of other triplets is already available. This can take different forms:
         Signaling the frame number modulo L (Field size ┌log 2  L┐). This can also be used for each triplet separately. Not that this is essentially sending the last L bits of the system frame number, thus the indication is relative to the system frame where last the numbers rolled over the bit higher than the L transmitted bits.   Signaling the slot offset to the feedback transmission: (Field size dependent on maximum distance). Note that it is possible that the initial transmission of the feedback is not received due to a decoding failure, half duplex problem or any reason leading to a missed transmission. In this case the retransmission is in a different slot with potentially no reference to the first one. This means this does not work for all cases. However, for SCI signaling as no HARQ combining needs to be assume different information about the slot can be send at different retransmissions of the same TB.   Signaling the slot offset to another a reference slot for resource allocation in time (Field size depending on maximum distance). In this case a frame is taken as a reference. This can either be another slot already signaled for another TRIV or take the feedback request as a reference. It is also possible that the feedback request contains a slot that should be used as a reference for the feedback transmission.       

     Signaling of the TRIV: 
     No changes need to be made to the TRIV as this contains already the full flexibility of signaling. It is however possible to adapt the window size of the TRIV the Rel. 16 version in clause 8.1.5 of 38.214 to a configurable window size. The current version is only allowing a window of 32 logical slots (This results in a maximum distance in slots as only the distance to the current slot is signaled). 
     Signaling of the FRIV: 
     FRIV indication assumes that due to the decoding of the PSCCH the starting sub-channel in the current slot is known. Thus, this is not signaled. However, this is not the case for signaling resource sets. There are the following options:
         Signaling of starting sub-channel for reference slot (Field size dependent on allocation size): To accommodate for the missing information signal the starting slot of the frequency resource in the reference slot.   Reinterpretation of starting sub-channel signaling. This means that the starting sub-channels of the current signaling would be reinterpreted and only up to 2 resource can be signaled. If sl-MaxNumPerReserve is configured as 2 than the starting sub-channel that would be signaled for the 2 nd  resource according to the Rel-16 definition is interpreted as the starting sub-channel of the only signaled resource. In the same fashion if MaxNumPerReserve is configured as 3 for the Rel-16 definition the starting sub-channel of the 2 nd  and 3 rd  resource are explicitly signaled. These would be reinterpreted as the starting sub-channel of the 1 st  and 2 nd  resource in the inter-UE coordination signaling.       

     Signaling of the Preserve: 
     As the resource pool configuration is limiting the set of Preserve an index relative to the allowed configurations is sufficient (Field size is dependent on the number of configured Preserve values). 
     Overhead Saving when Signaling Multiple Sets:
         Multiple sets could use the same reference slot relative to which the starting slot of each triplet is signaled or the n-th resource (e.g., n=1) of the k-th set can serve as a reference for (k+1)th resource set.   Multiple sets could use the same number of triplets N. This means these do not need to be signaled separately for each set.       

     Overhead Saving when Signaling Half Duplex Set: 
     As for this set only time information is necessary no transmission of the frequency allocation information with the FRIV is necessary. This means it can be omitted for this set. 
     Sidelink Communication with Inter-UE Coordination Feedback Over Multiple Containers 
     As discussed above, the inter-UE coordination framework is being developed in 3GPP Rel.17 to improve reliability of the sidelink communication by reducing probability of collisions. The main principle behind inter-UE coordination is delivery of feedback information to transmitters aiming to improve resource selection procedure considering feedback information from potential/target receivers. The inter-UE coordination feedback may contain information on preferred and non-preferred resource sets that are determined based on medium sensing procedure. The performance benefits from using inter-UE coordination solutions depend on the latency of the feedback delivery. The latency of feedback delivery depends on multiple factors, including channel access procedure and processing delays associated with a container carrying feedback information. There is also a tradeoff between amount of feedback information that can be delivered and latency of the delivery. 
     In various embodiments, two containers may be used for delivery of feedback information for NR sidelink communication: 1) Stage-2 SCI and 2) MAC CE signaling. The potential benefits for such embodiment are as follows: 1) SCI based solution can provide lower latency for a limited set of information and 2) MAC CE based solution can provide more information at the expense of latency increase. 
     In prior systems, there was no inter-UE coordination solutions defined for sidelink communication technology of cellular communication systems. The existing solutions for sidelink communication only consider TX based sensing procedure to select resource for transmission and do not utilize feedback from receivers. 
     The main disadvantage of the existing solution is not sufficient level of information on resource utilization and thus the lower achievable reliability level. 
     Various embodiments herein may include techniques for sidelink communication with inter-UE coordination feedback over multiple containers. The embodiments may provide one or more of the following advantages:
         Reduced latency of the inter-UE coordination feedback delivery   Increased reliability of sidelink V2X communication   Low incremental complexity as it reuses many of existing components of NR sidelink communication framework as well as timely delivery of inter-UE coordination information.       

     Latency Benefits 
     Latency benefit is a main argument to support stage-2 SCI container for inter-UE coordination feedback (preferred resource set) on top of MAC-CE container. The potential latency benefits of using stage-2 SCI container may come from reduced time for the following latency components:
         MAC-CE and Stage 2 SCI preparation time, including PSCCH/PSSCH preparation time   Transmission time and reception time
           PSCCH/PSSCH transmission duration, including number of retransmissions   Decoding time for PSCCH/PSSCH   
           MAC-CE vs Stage 2 SCI processing time       

     MAC-CE and Stage-2 SCI Preparation Time 
     The MAC-CE and Stage-2 SCI preparation time is expected to be different (e.g., by default Tprep,SCI2≤Tprep,MAC-CE) as different radio layers are used to deliver information (physical and MAC layer respectively). This may result in the use of different timelines and thus use of different preferred and/or non-preferred resource sets for signaling in Stage-2 SCI container and MAC-CE container. The meaning of “different” here mainly means that resource set carried in a container with lower preparation time may be less outdated (as it can be generated later) than resource set associated and carried in a container with higher preparation time (refer to  FIG.  1   ). 
     The resource set for inter-UE coordination feedback is expected to be updated every slot and thus information in Stage-2 SCI and MAC-CE containers may have different aging time and eventually may have some misalignment/mismatch (e.g., resource indicated as preferred in MAC-CE container may be detected as already reserved and thus not included in Stage-2 SCI container). This misalignment can be resolved at the UE that receives inter-UE coordination feedback and applies it for selection of resources for transmission. 
     In one embodiment, to simplify design, content of both containers can be associated with the same resource set corresponding to container with maximum preparation time (e.g., obtained corresponding to the max(Tprep,SCI2, Tprep,MAC-CE)). 
     To minimize outdate/aging time of inter-UE coordination feedback, the end slot of sensing window used for generation of preferred/non-preferred resource set should be determined by preparation time and time instance of initial transmission, so that only the most recent sensing results are included in inter-UE coordination feedback containers. In one embodiment, the time T3=Tproc,1 can be reused to bound MAC-CE and Stage-2 SCI preparation time(s) across all UEs. In another embodiment, the new and processing times can be defined for MAC CE and Stage-2 SCI preparation times and include PSCCH/PSSCH preparation time or defined on top of PSCCH/PSSCH preparation time as an additional processing delays at UE transmitting feedback. 
     Resource Selection for Stage-2 SCI 
     In one embodiment the Stage-2 SCI container is expected to carry inter-UE coordination information pointing to preferred resource set. In another embodiment, non-preferred resource set or both preferred and non-preferred resource sets can be signaled. UE behavior/procedure for selection of resources indicated in Stage-2 SCI container needs to be discussed so that latency benefits of using Stage-2 SCI container can be practically realized vs the MAC-CE option. 
     To achieve latency benefits, resources indicated in Stage-2 SCI should be selected from earlier in time resources of the resource set. Indicated resources should happen earlier than the slot associated with successful decoding and processing of MAC-CE, otherwise there is no latency gain comparing with the MAC-CE container. It should be clarified that time instance(s) for successful decoding and processing of Stage-2 SCI and MAC-CE is unknown in advance and may depends on number of retransmissions/retransmission index. 
     To extract latency benefits, the inter-UE coordination feedback resources indicated in Stage-2 SCI should meet the following timing condition(s): 
     
       
      
       t 
       TX-SCI-2,n 
       +T 
       proc,SCI-2 
       ≤t 
       res,m 
       ≤t 
       TX-MAC-CE,k 
       +T 
       proc,MAC-CE  
      
     
     
       
      
       t 
       RX-SCI-2,n 
       ≤t 
       TX-SCI-2,n 
       +T 
       proc,SCI-2  
      
     
     
       
      
       t 
       RX-MAC-CE,k 
       ≤t 
       TX-MAC-CE,k 
       +T 
       proc,MAC-CE  
      
     
     where,
         t RX-SCI-2,n —time instance/slot index, where Stage-2 SCI carrying preferred resource(s) is successfully decoded from the n-th transmission at slot t TX-SCI-2,n  (0&lt;n≤N 0 , where 0&lt;N 0 ≤32 is the number of (re)-transmissions) and processed
           here, t TX-SCI-2,n ≤t TX-SCI-2,n +T proc,SCI-2 ; where,
               T proc,SCI-2 —upper bound on Stage 2 SCI processing time at RX side (in another embodiment lower bound on Stage 2 SCI processing or actual stage 2 SCI processing time can be used);   t TX-SCI-2,n —time instance/slot index, where the n-th transmission of Stage-2 SCI container carrying feedback resource(s) is transmitted;   
               
           t res,m —time instance/slot index, corresponding to the m-th preferred resource carried in Stage-2 SCI (m=0, 1, 2, . . . , M, e.g., M=9);   t RX-MAC-CE,k —time instance/slot index, where MAC-CE carrying preferred resource(s) is successfully decoded from the k-th transmission (k≤K) and processed
           The t RX-MAC-CE,k ≤t TX-MAC-CE,k +T proc,MAC-CE ; where,
               T proc,MAC-CE — upper bound on MAC-CE processing time at RX side (in another embodiment lower bound on MAC-CE processing or actual MAC-CE processing time can be used)   t RX-MAC-CE,k —time instance/slot index, where the k-th transmission of MAC-CE carrying preferred resource(s) is transmitted   
               
               

       FIG.  2    illustrates an example of Stage-2 SCI and MAC-CE processing timelines, in accordance with various embodiments. 
     Example 1—Initial Transmission Only 
     For the case, when UE intends to transmit a TB only once (e.g., only initial transmission), the resources indicated in Stage-2 SCI should be within the window (t RX-SCI-2,1 =t TX-MAC-CE,1 =t TX,1 ) 
     
       
      
       t 
       TX-SCI-2,1 
       +T 
       proc,SCI-2 
       ≤t 
       res,m 
       ≤t 
       TX-MAC-CE,1 
       +T 
       proc,MAC-CE  
      
     
     
       
      
       t 
       TX,1 
       +T 
       proc,SCI-2 
       ≤t 
       res,m 
       ≤t 
       TX,1 
       +T 
       proc,MAC-CE  
      
     
     Indication of resources outside of this interval (represented by W 1A  in  FIG.  2   ) may either not have latency benefits (if (t TX,1 +T proc,MAC-CE )≤t res,m ) or result in outdated inter-UE coordination information (if t res,m ≤(t TX,1 +T proc,SCI-2 )). 
     Example 2—Initial Transmission+One Re-Transmission 
     For the case, when UE intends to transmit a TB two times (e.g., initial transmission and one re-transmission), the resources indicated in Stage-2 SCI should be either within
         1. Window W 1A : t TX-SCI-2,1 +T proc,SCI-2 ≤t res,m ≤t TX-MAC-CE,1 +T proc,MAC-CE  
           i. If both Stage-2 SCI and MAC-CE are expected to be received from initial transmission   
           2. Window W 1A +W 1B : t TX-MAC-CE,1 +T proc,MAC-CE ≤t res,m ≤t TX-SCI-2,2 +T proc,SCI-2  
           i. If Stage-2 SCI is received from initial transmission and MAC-CE is not received during initial transmission   
           3. Window W 2A : t TX-SCI-2,2 +T proc,SCI-2 ≤t res,m ≤t TX-MAC-CE,2 +T proc,MAC-CE  
           i. If Stage-2 SCI is received from the 1 st  re-transmission and MAC-CE is not received during initial transmission. There is no point to indicate resources in W 1A +W 1B , if Stage-2 SCI is not received from the initial transmission (outdated)   
           4. Window W 2A +W 2B : t TX-MAC-CE,2 +T proc,MAC-CE ≤t res,m ≤t TX-SCI-2,3 +T proc,SCI-2  
           i. Stage-2 SCI is received from the 1 st  re-transmission and MAC-CE is not received from the 1 st  re-transmission   
               

     Based on example 1 and 2, UE should select first in time resources for indication in Stage-2 SCI. There is no need to use k-th Stage-2 SCI, for indication of the m-th resource that satisfies the following condition (as it can be delivered in MAC-CE) 
     
       
      
       t 
       res,m 
       &gt;t 
       TX-MAC-CE,k 
       +T 
       proc,MAC-CE  
      
     
     Considering that Stage-2 SCI transmission cannot be combined (HARQ combining) it is beneficial to support indication of new resources in each Stage-2 SCI transmission. At the same time whether to indicate resources in Stage-2 SCI and whether to update resources in each Stage-2 SCI transmission should be left up to UE implementation as it depends on timing relationship of the resources for feedback and resources used for feedback transmission considering Stage 2 and MAC-CE processing delays. 
     Design Principles for Stage-2 SCI+MAC-CE for Inter-UE Coordination Feedback 
     The following design principles can be used for sidelink communication and inter-UE coordination feedback over Stage-2 SCI and MAC-CE containers:
         1. Preferred/non-preferred resource sets for inter-UE coordination feedback in MAC-CE container are generated T slots prior the slot with initial transmission carrying inter-UE coordination feedback
           i. The content of resource sets indicated in MAC-CE container does not change in subsequent re-transmission carrying the same TB   ii. MAC-CE includes time offset field pointing to the start slot of the resource selection window used for feedback or to the slot with the first in time resource of indicated resource sets. Alternatively, slot index of initial transmission or some other time reference can be used   
           2. First(early) in time resource selection procedure is applied to inter-UE coordination feedback resource set for determination of the sub-set of preferred/non-preferred resources indicated in Stage-2 SCI container. The following options can be used to determine windows for sub-set of preferred resources indicated in Stage-2 SCI:
           i. Option 1: Resources in time window, [n k +T proc,SCI-2 , n k +T proc,MAC-CE ], here n k  is a slot of k-th Stage-2 SCI transmission for a given TB (e.g., for initial transmission k=1)   ii. Option 2: Resources in time window, [n k +T proc,SCI-2 , n k+1 +T proc,SCI-2 ], here n k  is a slot of k-th Stage-2 SCI transmission for a given TB (e.g., for initial transmission k=1)   iii. Option 3: Resources in time window, [n k +T proc,SCI-2 , n k+1 +T proc,MAC-CE ], here n k  is a slot of k-th Stage-2 SCI transmission for a given TB (e.g., for initial transmission k=1)   iv. Option 4: Resources in time window, [n k +T proc,SCI-2 , n k+m +T proc,SCI-2 ], here n k  is a slot of k-th Stage-2 SCI transmission for a given TB (e.g., for initial transmission k=1)   v. Option 5: Resources in time window, [n k +T proc,SCI-2 , n k+m +T proc,MAC-CE ], here n k  is a slot of k-th Stage-2 SCI transmission for a given TB (e.g., for initial transmission k=1)   
           3. Re-evaluation of feedback resources indicated in Stage 2 SCI transmission(s) to provide the most recent feedback information
           i. Dynamic indication and update of feedback resources indicated in each Stage-2 SCI transmission   
           4. The following UE behaviors are possible in terms of selecting resources for indication in MAC-CE and Stage-2 SCI
           i. Option 1. The resource set(s) generated for MAC-CE container is re-used for determination of sub-set of resources indicated in Stage-2 SCI container in all transmissions of a given TB   ii. Option 2. The resource set(s) generated for MAC-CE container is re-used for determination of sub-set of resources indicated in Stage-2 SCI container. The sub-set of Stage-2 SCI resources is re-evaluated for all transmissions of a given TB using the valid set of resources indicated in MAC-CE   iii. Option 3. The resource set(s) for determination of sub-set of resources indicated in Stage-2 SCI container is re-evaluated for each transmission of a given TB (e.g., initial, and sub-sequent transmissions, or only sub-sequent transmissions)   iv. In all above options, the content of inter-UE coordination resource set(s) indicated in MAC-CE does not change during initial transmission and subsequent (re)-transmissions of a given TB, while the sub-set of resources indicated in Stage-2 SCI can be re-evaluated for initial transmission and sub-sequent (re)-transmissions or only sub-sequent (re)-transmissions.   
           5. Dynamic indication of the number of resources/resource combinations signaled in each Stage-2 SCI transmission {0, 1, 2, . . . , M}. Maximum number of resources indicated is configurable from {0, 1, 2, . . . , M}. If there is no resources (0 resources) then another SCI format can be used.   6. Dynamic indication of time offset/slot index in Stage-2 SCI container
           i. Time offset/slot index can be updated if indicated resources can change every re-transmission   ii. Implicit indication relative to slot carrying Stage-2 SCI   iii. Explicit indication inside stage-2 SCI   
           7. Duplication of indicated by Stage-2 SCI resources in MAC-CE
           i. MAC-CE content does not change during re-transmissions of a TB   ii. Duplication is used at least for initial transmission. For retransmissions, whether Stage-2 SCI content is duplicated is dependent on whether re-evaluation of feedback resources indicated in Stage 2 SCI is enabled/supported   
           8. Indication of fixed time offset/slot index in MAC-CE (e.g., start of resource selection window or pointer to the first in time resource in resource set)   9. Introduction and specification of upper bounds or lower bounds for Stage 2 SCI processing time and MAC-CE processing time   10. UE Stage 2 SCI processing time and MAC-CE processing time (including L1/L2 latency components) can be exchanged as a part of UE PC5 capability signaling, so that UEs can take it into account when prepare content (resources) for Stage-2 SCI container together with information on resources for feedback transmission.   11. Introduction and specification of upper bounds or lower bounds for Stage 2 SCI and MAC-CE preparation time   12. UE Stage 2 SCI preparation time and MAC-CE preparation time (including L1/L2 latency components) can be exchanged as a part of UE PC5 capability signaling, so that UEs can take it into account when prepare content for Stage-2 SCI container (preferred/non-preferred resources)       

     Systems and Implementations 
       FIGS.  3 - 5    illustrate various systems, devices, and components that may implement aspects of disclosed embodiments. 
       FIG.  3    illustrates a network  300  in accordance with various embodiments. The network  300  may operate in a manner consistent with 3GPP technical specifications for LTE or 5G/NR systems. However, the example embodiments are not limited in this regard and the described embodiments may apply to other networks that benefit from the principles described herein, such as future 3GPP systems, or the like. 
     The network  300  may include a UE  302 , which may include any mobile or non-mobile computing device designed to communicate with a RAN  304  via an over-the-air connection. The UE  302  may be communicatively coupled with the RAN  304  by a Uu interface. The UE  302  may be, but is not limited to, a smartphone, tablet computer, wearable computer device, desktop computer, laptop computer, in-vehicle infotainment, in-car entertainment device, instrument cluster, head-up display device, onboard diagnostic device, dashtop mobile equipment, mobile data terminal, electronic engine management system, electronic/engine control unit, electronic/engine control module, embedded system, sensor, microcontroller, control module, engine management system, networked appliance, machine-type communication device, M2M or D2D device, IoT device, etc. 
     In some embodiments, the network  300  may include a plurality of UEs coupled directly with one another via a sidelink interface. The UEs may be M2M/D2D devices that communicate using physical sidelink channels such as, but not limited to, PSBCH, PSDCH, PSSCH, PSCCH, PSFCH, etc. 
     In some embodiments, the UE  302  may additionally communicate with an AP  306  via an over-the-air connection. The AP  306  may manage a WLAN connection, which may serve to offload some/all network traffic from the RAN  304 . The connection between the UE  302  and the AP  306  may be consistent with any IEEE 802.11 protocol, wherein the AP  306  could be a wireless fidelity (Wi-Fi®) router. In some embodiments, the UE  302 , RAN  304 , and AP  306  may utilize cellular-WLAN aggregation (for example, LWA/LWIP). Cellular-WLAN aggregation may involve the UE  302  being configured by the RAN  304  to utilize both cellular radio resources and WLAN resources. 
     The RAN  304  may include one or more access nodes, for example, AN  308 . AN  308  may terminate air-interface protocols for the UE  302  by providing access stratum protocols including RRC, PDCP, RLC, MAC, and L1 protocols. In this manner, the AN  308  may enable data/voice connectivity between CN  320  and the UE  302 . In some embodiments, the AN  308  may be implemented in a discrete device or as one or more software entities running on server computers as part of, for example, a virtual network, which may be referred to as a CRAN or virtual baseband unit pool. The AN  308  be referred to as a BS, gNB, RAN node, eNB, ng-eNB, NodeB, RSU, TRxP, TRP, etc. The AN  308  may be a macrocell base station or a low power base station for providing femtocells, picocells or other like cells having smaller coverage areas, smaller user capacity, or higher bandwidth compared to macrocells. 
     In embodiments in which the RAN  304  includes a plurality of ANs, they may be coupled with one another via an X2 interface (if the RAN  304  is an LTE RAN) or an Xn interface (if the RAN  304  is a 5G RAN). The X2/Xn interfaces, which may be separated into control/user plane interfaces in some embodiments, may allow the ANs to communicate information related to handovers, data/context transfers, mobility, load management, interference coordination, etc. 
     The ANs of the RAN  304  may each manage one or more cells, cell groups, component carriers, etc. to provide the UE  302  with an air interface for network access. The UE  302  may be simultaneously connected with a plurality of cells provided by the same or different ANs of the RAN  304 . For example, the UE  302  and RAN  304  may use carrier aggregation to allow the UE  302  to connect with a plurality of component carriers, each corresponding to a Pcell or Scell. In dual connectivity scenarios, a first AN may be a master node that provides an MCG and a second AN may be secondary node that provides an SCG. The first/second ANs may be any combination of eNB, gNB, ng-eNB, etc. 
     The RAN  304  may provide the air interface over a licensed spectrum or an unlicensed spectrum. To operate in the unlicensed spectrum, the nodes may use LAA, eLAA, and/or feLAA mechanisms based on CA technology with PCells/Scells. Prior to accessing the unlicensed spectrum, the nodes may perform medium/carrier-sensing operations based on, for example, a listen-before-talk (LBT) protocol. 
     In V2X scenarios the UE  302  or AN  308  may be or act as a RSU, which may refer to any transportation infrastructure entity used for V2X communications. An RSU may be implemented in or by a suitable AN or a stationary (or relatively stationary) UE. An RSU implemented in or by: a UE may be referred to as a “UE-type RSU”; an eNB may be referred to as an “eNB-type RSU”; a gNB may be referred to as a “gNB-type RSU”; and the like. In one example, an RSU is a computing device coupled with radio frequency circuitry located on a roadside that provides connectivity support to passing vehicle UEs. The RSU may also include internal data storage circuitry to store intersection map geometry, traffic statistics, media, as well as applications/software to sense and control ongoing vehicular and pedestrian traffic. The RSU may provide very low latency communications required for high speed events, such as crash avoidance, traffic warnings, and the like. Additionally or alternatively, the RSU may provide other cellular/WLAN communications services. The components of the RSU may be packaged in a weatherproof enclosure suitable for outdoor installation, and may include a network interface controller to provide a wired connection (e.g., Ethernet) to a traffic signal controller or a backhaul network. 
     In some embodiments, the RAN  304  may be an LTE RAN  310  with eNBs, for example, eNB  312 . The LTE RAN  310  may provide an LTE air interface with the following characteristics: SCS of 15 kHz; CP-OFDM waveform for DL and SC-FDMA waveform for UL; turbo codes for data and TBCC for control; etc. The LTE air interface may rely on CSI-RS for CSI acquisition and beam management; PDSCH/PDCCH DMRS for PDSCH/PDCCH demodulation; and CRS for cell search and initial acquisition, channel quality measurements, and channel estimation for coherent demodulation/detection at the UE. The LTE air interface may operating on sub-6 GHz bands. 
     In some embodiments, the RAN  304  may be an NG-RAN  314  with gNBs, for example, gNB  316 , or ng-eNBs, for example, ng-eNB  318 . The gNB  316  may connect with 5G-enabled UEs using a 5G NR interface. The gNB  316  may connect with a 5G core through an NG interface, which may include an N2 interface or an N3 interface. The ng-eNB  318  may also connect with the 5G core through an NG interface, but may connect with a UE via an LTE air interface. The gNB  316  and the ng-eNB  318  may connect with each other over an Xn interface. 
     In some embodiments, the NG interface may be split into two parts, an NG user plane (NG-U) interface, which carries traffic data between the nodes of the NG-RAN  314  and a UPF  348  (e.g., N3 interface), and an NG control plane (NG-C) interface, which is a signaling interface between the nodes of the NG-RAN  314  and an AMF  344  (e.g., N2 interface). 
     The NG-RAN  314  may provide a 5G-NR air interface with the following characteristics: variable SCS; CP-OFDM for DL, CP-OFDM and DFT-s-OFDM for UL; polar, repetition, simplex, and Reed-Muller codes for control and LDPC for data. The 5G-NR air interface may rely on CSI-RS, PDSCH/PDCCH DMRS similar to the LTE air interface. The 5G-NR air interface may not use a CRS, but may use PBCH DMRS for PBCH demodulation; PTRS for phase tracking for PDSCH; and tracking reference signal for time tracking. The 5G-NR air interface may operating on FR1 bands that include sub-6 GHz bands or FR2 bands that include bands from 24.25 GHz to 52.6 GHz. The 5G-NR air interface may include an SSB that is an area of a downlink resource grid that includes PSS/SSS/PBCH. 
     In some embodiments, the 5G-NR air interface may utilize BWPs for various purposes. For example, BWP can be used for dynamic adaptation of the SCS. For example, the UE  302  can be configured with multiple BWPs where each BWP configuration has a different SCS. When a BWP change is indicated to the UE  302 , the SCS of the transmission is changed as well. Another use case example of BWP is related to power saving. In particular, multiple BWPs can be configured for the UE  302  with different amount of frequency resources (for example, PRBs) to support data transmission under different traffic loading scenarios. A BWP containing a smaller number of PRBs can be used for data transmission with small traffic load while allowing power saving at the UE  302  and in some cases at the gNB  316 . A BWP containing a larger number of PRBs can be used for scenarios with higher traffic load. 
     The RAN  304  is communicatively coupled to CN  320  that includes network elements to provide various functions to support data and telecommunications services to customers/subscribers (for example, users of UE  302 ). The components of the CN  320  may be implemented in one physical node or separate physical nodes. In some embodiments, NFV may be utilized to virtualize any or all of the functions provided by the network elements of the CN  320  onto physical compute/storage resources in servers, switches, etc. A logical instantiation of the CN  320  may be referred to as a network slice, and a logical instantiation of a portion of the CN  320  may be referred to as a network sub-slice. 
     In some embodiments, the CN  320  may be an LTE CN  322 , which may also be referred to as an EPC. The LTE CN  322  may include MME  324 , SGW  326 , SGSN  328 , HSS  330 , PGW  332 , and PCRF  334  coupled with one another over interfaces (or “reference points”) as shown. Functions of the elements of the LTE CN  322  may be briefly introduced as follows. 
     The MME  324  may implement mobility management functions to track a current location of the UE  302  to facilitate paging, bearer activation/deactivation, handovers, gateway selection, authentication, etc. 
     The SGW  326  may terminate an S1 interface toward the RAN and route data packets between the RAN and the LTE CN  322 . The SGW  326  may be a local mobility anchor point for inter-RAN node handovers and also may provide an anchor for inter-3GPP mobility. Other responsibilities may include lawful intercept, charging, and some policy enforcement. 
     The SGSN  328  may track a location of the UE  302  and perform security functions and access control. In addition, the SGSN  328  may perform inter-EPC node signaling for mobility between different RAT networks; PDN and S-GW selection as specified by MME  324 ; MME selection for handovers; etc. The S3 reference point between the MME  324  and the SGSN  328  may enable user and bearer information exchange for inter-3GPP access network mobility in idle/active states. 
     The HSS  330  may include a database for network users, including subscription-related information to support the network entities&#39; handling of communication sessions. The HSS  330  can provide support for routing/roaming, authentication, authorization, naming/addressing resolution, location dependencies, etc. An S6a reference point between the HSS  330  and the MME  324  may enable transfer of subscription and authentication data for authenticating/authorizing user access to the LTE CN  320 . 
     The PGW  332  may terminate an SGi interface toward a data network (DN)  336  that may include an application/content server  338 . The PGW  332  may route data packets between the LTE CN  322  and the data network  336 . The PGW  332  may be coupled with the SGW  326  by an S5 reference point to facilitate user plane tunneling and tunnel management. The PGW  332  may further include a node for policy enforcement and charging data collection (for example, PCEF). Additionally, the SGi reference point between the PGW  332  and the data network  3   36  may be an operator external public, a private PDN, or an intra-operator packet data network, for example, for provision of IMS services. The PGW  332  may be coupled with a PCRF  334  via a Gx reference point. 
     The PCRF  334  is the policy and charging control element of the LTE CN  322 . The PCRF  334  may be communicatively coupled to the app/content server  338  to determine appropriate QoS and charging parameters for service flows. The PCRF  332  may provision associated rules into a PCEF (via Gx reference point) with appropriate TFT and QCI. 
     In some embodiments, the CN  320  may be a 5GC  340 . The 5GC  340  may include an AUSF  342 , AMF  344 , SMF  346 , UPF  348 , NSSF  350 , NEF  352 , NRF  354 , PCF  356 , UDM  358 , and AF  360  coupled with one another over interfaces (or “reference points”) as shown. Functions of the elements of the 5GC  340  may be briefly introduced as follows. 
     The AUSF  342  may store data for authentication of UE  302  and handle authentication-related functionality. The AUSF  342  may facilitate a common authentication framework for various access types. In addition to communicating with other elements of the 5GC  340  over reference points as shown, the AUSF  342  may exhibit an Nausf service-based interface. 
     The AMF  344  may allow other functions of the 5GC  340  to communicate with the UE  302  and the RAN  304  and to subscribe to notifications about mobility events with respect to the UE  302 . The AMF  344  may be responsible for registration management (for example, for registering UE  302 ), connection management, reachability management, mobility management, lawful interception of AMF-related events, and access authentication and authorization. The AMF  344  may provide transport for SM messages between the UE  302  and the SMF  346 , and act as a transparent proxy for routing SM messages. AMF  344  may also provide transport for SMS messages between UE  302  and an SMSF. AMF  344  may interact with the AUSF  342  and the UE  302  to perform various security anchor and context management functions. Furthermore, AMF  344  may be a termination point of a RAN CP interface, which may include or be an N2 reference point between the RAN  304  and the AMF  344 ; and the AMF  344  may be a termination point of NAS (N1) signaling, and perform NAS ciphering and integrity protection. AMF  344  may also support NAS signaling with the UE  302  over an N3 IWF interface. 
     The SMF  346  may be responsible for SM (for example, session establishment, tunnel management between UPF  348  and AN  308 ); UE IP address allocation and management (including optional authorization); selection and control of UP function; configuring traffic steering at UPF  348  to route traffic to proper destination; termination of interfaces toward policy control functions; controlling part of policy enforcement, charging, and QoS; lawful intercept (for SM events and interface to LI system); termination of SM parts of NAS messages; downlink data notification; initiating AN specific SM information, sent via AMF  344  over N2 to AN  308 ; and determining SSC mode of a session. SM may refer to management of a PDU session, and a PDU session or “session” may refer to a PDU connectivity service that provides or enables the exchange of PDUs between the UE  302  and the data network  336 . 
     The UPF  348  may act as an anchor point for intra-RAT and inter-RAT mobility, an external PDU session point of interconnect to data network  336 , and a branching point to support multi-homed PDU session. The UPF  348  may also perform packet routing and forwarding, perform packet inspection, enforce the user plane part of policy rules, lawfully intercept packets (UP collection), perform traffic usage reporting, perform QoS handling for a user plane (e.g., packet filtering, gating, UL/DL rate enforcement), perform uplink traffic verification (e.g., SDF-to-QoS flow mapping), transport level packet marking in the uplink and downlink, and perform downlink packet buffering and downlink data notification triggering. UPF  348  may include an uplink classifier to support routing traffic flows to a data network. 
     The NSSF  350  may select a set of network slice instances serving the UE  302 . The NSSF  350  may also determine allowed NSSAI and the mapping to the subscribed S-NSSAIs, if needed. The NSSF  350  may also determine the AMF set to be used to serve the UE  302 , or a list of candidate AMFs based on a suitable configuration and possibly by querying the NRF  354 . The selection of a set of network slice instances for the UE  302  may be triggered by the AMF  344  with which the UE  302  is registered by interacting with the NSSF  350 , which may lead to a change of AMF. The NSSF  350  may interact with the AMF  344  via an N22 reference point; and may communicate with another NSSF in a visited network via an N31 reference point (not shown). Additionally, the NSSF  350  may exhibit an Nnssf service-based interface. 
     The NEF  352  may securely expose services and capabilities provided by 3GPP network functions for third party, internal exposure/re-exposure, AFs (e.g., AF  360 ), edge computing or fog computing systems, etc. In such embodiments, the NEF  352  may authenticate, authorize, or throttle the AFs. NEF  352  may also translate information exchanged with the AF  360  and information exchanged with internal network functions. For example, the NEF  352  may translate between an AF-Service-Identifier and an internal 5GC information. NEF  352  may also receive information from other NFs based on exposed capabilities of other NFs. This information may be stored at the NEF  352  as structured data, or at a data storage NF using standardized interfaces. The stored information can then be re-exposed by the NEF  352  to other NFs and AFs, or used for other purposes such as analytics. Additionally, the NEF  352  may exhibit an Nnef service-based interface. 
     The NRF  354  may support service discovery functions, receive NF discovery requests from NF instances, and provide the information of the discovered NF instances to the NF instances. NRF  354  also maintains information of available NF instances and their supported services. As used herein, the terms “instantiate,” “instantiation,” and the like may refer to the creation of an instance, and an “instance” may refer to a concrete occurrence of an object, which may occur, for example, during execution of program code. Additionally, the NRF  354  may exhibit the Nnrf service-based interface. 
     The PCF  356  may provide policy rules to control plane functions to enforce them, and may also support unified policy framework to govern network behavior. The PCF  356  may also implement a front end to access subscription information relevant for policy decisions in a UDR of the UDM  358 . In addition to communicating with functions over reference points as shown, the PCF  356  exhibit an Npcf service-based interface. 
     The UDM  358  may handle subscription-related information to support the network entities&#39; handling of communication sessions, and may store subscription data of UE  302 . For example, subscription data may be communicated via an N8 reference point between the UDM  358  and the AMF  344 . The UDM  358  may include two parts, an application front end and a UDR. The UDR may store subscription data and policy data for the UDM  358  and the PCF  356 , and/or structured data for exposure and application data (including PFDs for application detection, application request information for multiple UEs  302 ) for the NEF  352 . The Nudr service-based interface may be exhibited by the UDR  221  to allow the UDM  358 , PCF  356 , and NEF  352  to access a particular set of the stored data, as well as to read, update (e.g., add, modify), delete, and subscribe to notification of relevant data changes in the UDR. The UDM may include a UDM-FE, which is in charge of processing credentials, location management, subscription management and so on. Several different front ends may serve the same user in different transactions. The UDM-FE accesses subscription information stored in the UDR and performs authentication credential processing, user identification handling, access authorization, registration/mobility management, and subscription management. In addition to communicating with other NFs over reference points as shown, the UDM  358  may exhibit the Nudm service-based interface. 
     The AF  360  may provide application influence on traffic routing, provide access to NEF, and interact with the policy framework for policy control. 
     In some embodiments, the 5GC  340  may enable edge computing by selecting operator/3rd party services to be geographically close to a point that the UE  302  is attached to the network. This may reduce latency and load on the network. To provide edge-computing implementations, the 5GC  340  may select a UPF  348  close to the UE  302  and execute traffic steering from the UPF  348  to data network  336  via the N6 interface. This may be based on the UE subscription data, UE location, and information provided by the AF  360 . In this way, the AF  360  may influence UPF (re)selection and traffic routing. Based on operator deployment, when AF  360  is considered to be a trusted entity, the network operator may permit AF  360  to interact directly with relevant NFs. Additionally, the AF  360  may exhibit an Naf service-based interface. 
     The data network  336  may represent various network operator services, Internet access, or third party services that may be provided by one or more servers including, for example, application/content server  338 . 
       FIG.  4    schematically illustrates a wireless network  400  in accordance with various embodiments. The wireless network  400  may include a UE  402  in wireless communication with an AN  404 . The UE  402  and AN  404  may be similar to, and substantially interchangeable with, like-named components described elsewhere herein. 
     The UE  402  may be communicatively coupled with the AN  404  via connection  406 . The connection  406  is illustrated as an air interface to enable communicative coupling, and can be consistent with cellular communications protocols such as an LTE protocol or a 5G NR protocol operating at mmWave or sub-6 GHz frequencies. 
     The UE  402  may include a host platform  408  coupled with a modem platform  410 . The host platform  408  may include application processing circuitry  412 , which may be coupled with protocol processing circuitry  414  of the modem platform  410 . The application processing circuitry  412  may run various applications for the UE  402  that source/sink application data. The application processing circuitry  412  may further implement one or more layer operations to transmit/receive application data to/from a data network. These layer operations may include transport (for example UDP) and Internet (for example, IP) operations 
     The protocol processing circuitry  414  may implement one or more of layer operations to facilitate transmission or reception of data over the connection  406 . The layer operations implemented by the protocol processing circuitry  414  may include, for example, MAC, RLC, PDCP, RRC and NAS operations. 
     The modem platform  410  may further include digital baseband circuitry  416  that may implement one or more layer operations that are “below” layer operations performed by the protocol processing circuitry  414  in a network protocol stack. These operations may include, for example, PHY operations including one or more of HARQ-ACK functions, scrambling/descrambling, encoding/decoding, layer mapping/de-mapping, modulation symbol mapping, received symbol/bit metric determination, multi-antenna port precoding/decoding, which may include one or more of space-time, space-frequency or spatial coding, reference signal generation/detection, preamble sequence generation and/or decoding, synchronization sequence generation/detection, control channel signal blind decoding, and other related functions. 
     The modem platform  410  may further include transmit circuitry  418 , receive circuitry  420 , RF circuitry  422 , and RF front end (RFFE)  424 , which may include or connect to one or more antenna panels  426 . Briefly, the transmit circuitry  418  may include a digital-to-analog converter, mixer, intermediate frequency (IF) components, etc.; the receive circuitry  420  may include an analog-to-digital converter, mixer, IF components, etc.; the RF circuitry  422  may include a low-noise amplifier, a power amplifier, power tracking components, etc.; RFFE  424  may include filters (for example, surface/bulk acoustic wave filters), switches, antenna tuners, beamforming components (for example, phase-array antenna components), etc. The selection and arrangement of the components of the transmit circuitry  418 , receive circuitry  420 , RF circuitry  422 , RFFE  424 , and antenna panels  426  (referred generically as “transmit/receive components”) may be specific to details of a specific implementation such as, for example, whether communication is TDM or FDM, in mmWave or sub-6 gHz frequencies, etc. In some embodiments, the transmit/receive components may be arranged in multiple parallel transmit/receive chains, may be disposed in the same or different chips/modules, etc. 
     In some embodiments, the protocol processing circuitry  414  may include one or more instances of control circuitry (not shown) to provide control functions for the transmit/receive components. 
     A UE reception may be established by and via the antenna panels  426 , RFFE  424 , RF circuitry  422 , receive circuitry  420 , digital baseband circuitry  416 , and protocol processing circuitry  414 . In some embodiments, the antenna panels  426  may receive a transmission from the AN  404  by receive-beamforming signals received by a plurality of antennas/antenna elements of the one or more antenna panels  426 . 
     A UE transmission may be established by and via the protocol processing circuitry  414 , digital baseband circuitry  416 , transmit circuitry  418 , RF circuitry  422 , RFFE  424 , and antenna panels  426 . In some embodiments, the transmit components of the UE  404  may apply a spatial filter to the data to be transmitted to form a transmit beam emitted by the antenna elements of the antenna panels  426 . 
     Similar to the UE  402 , the AN  404  may include a host platform  428  coupled with a modem platform  430 . The host platform  428  may include application processing circuitry  432  coupled with protocol processing circuitry  434  of the modem platform  430 . The modem platform may further include digital baseband circuitry  436 , transmit circuitry  438 , receive circuitry  440 , RF circuitry  442 , RFFE circuitry  444 , and antenna panels  446 . The components of the AN  404  may be similar to and substantially interchangeable with like-named components of the UE  402 . In addition to performing data transmission/reception as described above, the components of the AN  408  may perform various logical functions that include, for example, RNC functions such as radio bearer management, uplink and downlink dynamic radio resource management, and data packet scheduling. 
       FIG.  5    is a block diagram illustrating components, according to some example embodiments, able to read instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium) and perform any one or more of the methodologies discussed herein. Specifically,  FIG.  5    shows a diagrammatic representation of hardware resources  500  including one or more processors (or processor cores)  510 , one or more memory/storage devices  520 , and one or more communication resources  530 , each of which may be communicatively coupled via a bus  540  or other interface circuitry. For embodiments where node virtualization (e.g., NFV) is utilized, a hypervisor  502  may be executed to provide an execution environment for one or more network slices/sub-slices to utilize the hardware resources  500 . 
     The processors  510  may include, for example, a processor  512  and a processor  514 . The processors  510  may be, for example, a central processing unit (CPU), a reduced instruction set computing (RISC) processor, a complex instruction set computing (CISC) processor, a graphics processing unit (GPU), a DSP such as a baseband processor, an ASIC, an FPGA, a radio-frequency integrated circuit (RFIC), another processor (including those discussed herein), or any suitable combination thereof. 
     The memory/storage devices  520  may include main memory, disk storage, or any suitable combination thereof. The memory/storage devices  520  may include, but are not limited to, any type of volatile, non-volatile, or semi-volatile memory such as 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 storage, etc. 
     The communication resources  530  may include interconnection or network interface controllers, components, or other suitable devices to communicate with one or more peripheral devices  504  or one or more databases  506  or other network elements via a network  508 . For example, the communication resources  530  may include wired communication components (e.g., for coupling via USB, Ethernet, etc.), cellular communication components, NFC components, Bluetooth® (or Bluetooth® Low Energy) components, Wi-Fi® components, and other communication components. 
     Instructions  550  may comprise software, a program, an application, an applet, an app, or other executable code for causing at least any of the processors  510  to perform any one or more of the methodologies discussed herein. The instructions  550  may reside, completely or partially, within at least one of the processors  510  (e.g., within the processor&#39;s cache memory), the memory/storage devices  520 , or any suitable combination thereof. Furthermore, any portion of the instructions  550  may be transferred to the hardware resources  500  from any combination of the peripheral devices  504  or the databases  506 . Accordingly, the memory of processors  510 , the memory/storage devices  520 , the peripheral devices  504 , and the databases  506  are examples of computer-readable and machine-readable media. 
     Example Procedures 
     In some embodiments, the electronic device(s), network(s), system(s), chip(s) or component(s), or portions or implementations thereof, of  FIGS.  3 - 5   , or some other figure herein, may be configured to perform one or more processes, techniques, or methods as described herein, or portions thereof. One such process  600  is depicted in  FIG.  6   . The process  600  may be performed by a user equipment (UE) in a 5G network, or a portion thereof. At  602 , the process  600  may include receiving an indication of a first resource set for inter-UE coordination information from another UE for sidelink communication. At  604 , the process  600  may further include selecting a second resource set for a transmission by the UE based on the first resource set, wherein resources of the first resource set are excluded from consideration for the second resource set if the feedback information is to be transmitted using medium access control-control element (MAC-CE) signaling and sidelink control information (SCI) signaling and the resources are after a first time period from the indication, and wherein resources of the first resource set are excluded from consideration for the second resource set if the feedback information is to be transmitted using only MAC-CE signaling and the resources are after a second time period from the indication, wherein the second time period is longer than the first time period. 
     For one or more embodiments, at least one of the components set forth in one or more of the preceding figures may be configured to perform one or more operations, techniques, processes, and/or methods as set forth in the example section below. For example, the baseband circuitry as described above in connection with one or more of the preceding figures may be configured to operate in accordance with one or more of the examples set forth below. For another example, circuitry associated with a UE, base station, network element, etc. as described above in connection with one or more of the preceding figures may be configured to operate in accordance with one or more of the examples set forth below in the example section. 
     Examples 
     Example A1 may include an inter-UE coordination resource set signaling scheme 
     Example A2 may include the scheme in example A1 or some other example herein, where the resource set(s) are transmitted in the 2nd stage SCI 
     Example A3 may include the scheme in example A2 or some other example herein, where the presence of inter-UE coordination information is indicated in the 1st stage SCI
         a. The scheme in 3 where the presence of one following combination of resource sets is present in the 2 nd  stage SCI is signaled in the first stage:
           i. Preferred resource set   ii. Non-preferred resource set   iii. Non-preferred half duplex set   iv. Any combination of the above   
               

     Example A4 may include the scheme in example A2 or some other example herein, where the 1st stage SCI is indicating the presence of only one resource set of the following list in addition to signaling the number of resources in the set.
         i. Preferred resource set   ii. Non-preferred resource set   iii. Non-preferred half duplex set       

     Example A5 may include the scheme in example A2 or some other example herein, where only the presence of inter-UE coordination information is indicated in the 1st stage SCI and which resource set and the number of resources is used is indicated in the 2nd stage itself 
     Example A6 may include the scheme in example A2 or some other example herein, where the 2nd stage SCI is split into a section based on Rel. 16 2nd stage formats and one section for inter-UE coordination. 
     Example A7 may include the scheme in example A2 or some other example herein, where the 2nd stage SCI contains the following fields per resource set 
     a. Number of resources 
     b. Time resource indicator values 
     c. Frequency resource indicator values 
     d. Preserve value 
     e. Starting time slot of each triplet 
     f. Starting sub-channel for one additional slot 
     g. Any combination of the above 
     Example A8 may include the SCI content in example A7 or some other example herein, where the starting slot of a triplet is signaled as 
     a. With respect to previous agreed reference slot 
     b. First one relative to the slot which contains the SCI 
     c. All except the first one relative to the preceding one 
     d. The last L bits of the system frame number 
     Example A9 may include the scheme in example A2 or some other example herein, where the following parameters are (pre)-configured, part of the inter-UE coordination feedback request or are agreed during the uni/groupcast connection setup: 
     a. Number of reserved resources per TRIV 
     b. Number of triplets signaled in the SCI 
     Example A10 may include the scheme in example A1 or some other example herein, where the resource set(s) are transmitted in a MAC CE container 
     Example All may include the scheme in example A10 or some other example herein, where the following resource sets are signaled: 
     a. Preferred resource set 
     b. Non-preferred resource set 
     c. Non-preferred half duplex set 
     d. Any combination of the above 
     Example A12 may include the scheme in example A10 or some other example herein, where the following information is signaled pers resource set: 
     a. Number of resources 
     b. Time resource indicator values 
     c. Frequency resource indicator values 
     d. Preserve value 
     e. Starting time slot of each triplet 
     f. Starting sub-channel for one additional slot 
     g. Any combination of the above 
     Example A13 may include the MAC CE content per resource set in example A12 or some other example herein, where the starting slot of a triplet is signaled as 
     a. With respect to previous agreed reference slot 
     b. All except the first one relative to the preceding one 
     c. The last L bits of the system frame number 
     Example A14 may include the scheme in example A10 or some other example herein where the following parameters are (pre)-configured, part of the inter-UE coordination feedback request or are agreed during the uni/groupcast connection setup: 
     a. Number of reserved resources per TRIV 
     b. Number of triplets signaled in the SCI 
     Example B1 may include a method of sidelink inter-UE coordination feedback over two radio-layer containers: Stage-2 SCI over physical layer and MAC-CE over L2 signaling. 
     Example B2 may include the method of example B1 or some other example herein, wherein MAC-CE container carries full inter-UE coordination feedback or on preferred or non-preferred resources sets. 
     Example B3 may include the method of example B2 or some other example herein, wherein content of MAC-CE inter-UE coordination feedback on preferred or non-preferred resources sets is generated Tproc,1 before initial transmission and does not change during retransmissions. 
     Example B4 may include the method of example B1 or some other example herein, wherein Stage-2 SCI container carries latency-critical part of inter-UE coordination feedback on preferred or non-preferred resources sets for initial transmission. 
     Example B5 may include the method of example B4 or some other example herein, wherein Stage-2 SCI container carries early(first) in time resources from preferred or non-preferred resource sets. 
     Example B6 may include the method of example B4 or some other example herein, wherein Stage-2 SCI content is re-evaluated and updated for each Stage-2 SCI transmission of a given TB, based on resource sets generated before initial transmission or re-evaluated resource sets. 
     Example B7 may include the method of example B4 or some other example herein, wherein Stage-2 SCI provides dynamic indication of the number of resources/resource combinations signaled in each Stage-2 SCI transmission {0, 1, 2, . . . , M}. Maximum number of resources indicated is configurable from {0, 1, 2, . . . , M}. If there is no resources (0 resources) then another SCI format can be used. 
     Example B8 may include the method of example B1 or some other example herein, wherein upper or lower bounds are defined for preparation time of Stage-2 SCI or MAC-CE containers carrying inter-UE coordination information. 
     Example B9 may include the method of example B1 or some other example herein, wherein upper or lower bounds are defined for processing time of Stage-2 SCI or MAC-CE containers carrying inter-UE coordination information. 
     Example B10 may include the method of example B1 or some other example herein, wherein MAC-CE includes time offset field pointing to the start slot of the resource selection window used for feedback or to the slot with the first in time resource of indicated resource sets. Alternatively, slot index of initial transmission or some other time reference can be used. 
     Example B11 may include UE Stage 2 SCI and MAC-CE processing or preparation time are exchanged as a part of UE PC5 capability signaling. 
     Example B12 may include a method of a UE, the method comprising: 
     generating UE coordination feedback information for sidelink communication; 
     encoding a first portion of the UE coordination feedback information for transmission in a sidelink control information (SCI); and 
     encoding a second portion of the UE coordination feedback information for transmission in a medium access control (MAC) control element (CE). 
     Example B13 includes a method to be performed by a user equipment (UE) in a fifth generation (5G) cellular network, wherein the method comprises: identifying, by the UE, an indication in first or second stage sidelink control information (SCI); identifying, in the second stage SCI by the UE based on the indication, an indication of one or more resource sets; and performing, by the UE, inter-UE coordination signaling based on the one or more resource sets. 
     Example C1 includes one or more non-transitory computer-readable media (NTCRM) having instructions, stored thereon, that when executed by one or more processors of a user equipment (UE) configure the UE to: receive an indication of a first resource set for inter-UE coordination information from another UE for sidelink communication; and select a second resource set for a transmission by the UE based on the first resource set, wherein resources of the first resource set are excluded from consideration for the second resource set if the feedback information is to be transmitted using medium access control-control element (MAC-CE) signaling and sidelink control information (SCI) signaling and the resources are after a first time period from the indication, and wherein resources of the first resource set are excluded from consideration for the second resource set if the feedback information is to be transmitted using only MAC-CE signaling and the resources are after a second time period from the indication, wherein the second time period is longer than the first time period. 
     Example C2 includes the one or more NTCRM of example C1, wherein: the first time period corresponds to a first processing time; and the second time period corresponds to the first processing time plus a second processing time. 
     Example C3 includes the one or more NTCRM of example C1, wherein the first resource set includes a same set of resources for an initial MAC-CE transmission and a MAC-CE re-transmission. 
     Example C4 includes the one or more NTCRM of example C1, wherein the instructions, when executed, are further to configure the UE to send the transmission using the selected second resource set. 
     Example C5 includes the one or more NTCRM of example C1, wherein the first resource set is a non-preferred resource set. 
     Example C6 includes the one or more NTCRM of example C1, wherein the indication of the first resource set is included in a SCI. 
     Example C7 includes the one or more NTCRM of example C6, wherein the SCI includes a resource set type to indicate whether the first resource set is a preferred resource set or a non-preferred resource set. 
     Example C8 includes the one or more NTCRM of example C6, wherein the SCI indicates multiple sets of resources, wherein each set of resources is indicated by a respective time resource indicator, a frequency resource indicator, and a resource reservation period. 
     Example C9 includes one or more non-transitory computer-readable media (NTCRM) having instructions, stored thereon, that when executed by one or more processors of a user equipment (UE) configure the UE to: receive a second stage sidelink control information (SCI) that includes an indication of resources for UE coordination information for sidelink communication; and decode the UE coordination information according to the indicated resources. 
     Example C10 includes the one or more NTCRM of example C9, wherein the SCI includes a resource set type to indicate whether the resources correspond to a preferred resource set or a non-preferred resource set. 
     Example C11 includes the one or more NTCRM of example C9, wherein the SCI indicates multiple sets of resources, wherein each set of resources is indicated by a respective time resource indicator, a frequency resource indicator, and a resource reservation period. 
     Example C12 includes the one or more NTCRM of example C11, wherein a sl-MaxNumPerReserve value associated with each set of resources is the same or different. 
     Example C13 includes the one or more NTCRM of example C9, wherein the resources are to be used for one or both of SCI signaling and medium access control-control element (MAC-CE) signaling. 
     Example C14 includes the one or more NTCRM of example C9, wherein the instructions, when executed, are further to configure the UE to receive a first stage SCI that includes an indication that the second stage SCI includes the UE coordination information. 
     Example C15 includes the one or more NTCRM of example C9, wherein the indication of resources includes an indication of a starting slot for the resources. 
     Example C16 includes the one or more NTCRM of example C9, wherein the indication of resources includes an indication of a number of resources in a resource set. 
     Example C17 includes the one or more NTCRM of example C9, wherein the second stage SCI further includes an indication of a set of the UE coordination information that is included in the SCI. 
     Example Z01 may include an apparatus comprising means to perform one or more elements of a method described in or related to any of examples A1-A14, B1-B13, C1-C17, or any other method or process described herein. 
     Example Z02 may include one or more non-transitory computer-readable media comprising instructions to cause an electronic device, upon execution of the instructions by one or more processors of the electronic device, to perform one or more elements of a method described in or related to any of examples A1-A14, B1-B13, C1-C17, or any other method or process described herein. 
     Example Z03 may include an apparatus comprising logic, modules, or circuitry to perform one or more elements of a method described in or related to any of examples A1-A14, B1-B13, C1-C17, or any other method or process described herein. 
     Example Z04 may include a method, technique, or process as described in or related to any of examples A1-A14, B1-B13, C1-C17, or portions or parts thereof. 
     Example Z05 may include an apparatus comprising: one or more processors and 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 the method, techniques, or process as described in or related to any of examples A1-A14, B1-B13, C1-C17, or portions thereof. 
     Example Z06 may include a signal as described in or related to any of examples A1-A14, B1-B13, C1-C17, or portions or parts thereof. 
     Example Z07 may include a datagram, packet, frame, segment, protocol data unit (PDU), or message as described in or related to any of examples A1-A14, B1-B13, C1-C17, or portions or parts thereof, or otherwise described in the present disclosure. 
     Example Z08 may include a signal encoded with data as described in or related to any of examples A1-A14, B1-B13, C1-C17, or portions or parts thereof, or otherwise described in the present disclosure. 
     Example Z09 may include a signal encoded with a datagram, packet, frame, segment, protocol data unit (PDU), or message as described in or related to any of examples A1-A14, B1-B13, C1-C17, or portions or parts thereof, or otherwise described in the present disclosure. 
     Example Z10 may include an electromagnetic signal carrying computer-readable instructions, wherein execution of the computer-readable instructions by one or more processors is to cause the one or more processors to perform the method, techniques, or process as described in or related to any of examples A1-A14, B1-B13, C1-C17, or portions thereof. 
     Example Z11 may include a computer program comprising instructions, wherein execution of the program by a processing element is to cause the processing element to carry out the method, techniques, or process as described in or related to any of examples A1-A14, B1-B13, C1-C17, or portions thereof. 
     Example Z12 may include a signal in a wireless network as shown and described herein. 
     Example Z13 may include a method of communicating in a wireless network as shown and described herein. 
     Example Z14 may include a system for providing wireless communication as shown and described herein. 
     Example Z15 may include a device for providing wireless communication as shown and described herein. 
     Any of the above-described examples may be combined with any other example (or combination of examples), unless explicitly stated otherwise. The foregoing description of one or more implementations provides illustration and description, but is not intended to be exhaustive or to limit the scope of embodiments to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of various embodiments. 
     Abbreviations 
     Unless used differently herein, terms, definitions, and abbreviations may be consistent with terms, definitions, and abbreviations defined in 3GPP TR 21.905 v16.0.0 (2019-06). For the purposes of the present document, the following abbreviations may apply to the examples and embodiments discussed herein.
     3GPP Third Generation ARP Allocation and C-RNTI Cell Radio Partnership Project Retention Priority Network Temporary   4G Fourth Generation ARQ Automatic Repeat Identity   5G Fifth Generation Request CA Carrier Aggregation,   5GC 5G Core network AS Access Stratum Certification   AC Application ASP Application Authority   Client Service Provider CAPEX CAPital   ACR Application Context EXpenditure   Relocation ASN.1 Abstract Syntax CBRA Contention Based   ACK Acknowledgement Notation One Random Access   ACID Application AUSF Authentication CC Component Carrier,   Client Identification Server Function Country Code,   AF Application AWGN Additive Cryptographic   Function White Gaussian Noise Checksum   AM Acknowledged BAP Backhaul CCA Clear Channel   Mode Adaptation Protocol Assessment   AMBRAggregate BCH Broadcast Channel CCE Control Channel   Maximum Bit Rate BER Bit Error Ratio Element   AMF Access and Mobility BFD Beam Failure CCCH Common Control Management Detection Channel   Function BLER Block Error Rate CE Coverage   AN Access Network BPSK Binary Phase Shift Enhancement   ANR Automatic Keying CDM Content Delivery   Neighbour Relation BRAS Broadband Remote Network   AOA Angle of Access Server CDMA Code-Arrival BSS Business Support Division Multiple   AP Application System Access   Protocol, Antenna BS Base Station CDR Charging Data   Port, Access Point BSR Buffer Status Report Request   API Application BW Bandwidth CDR Charging Data   Programming Interface BWP Bandwidth Part Response   APN Access Point Name CFRA Contention Free Random Access   CG Cell Group CPD Connection Point CSI-IM CSI   CGF Charging Descriptor Interference   Gateway Function CPE Customer Premise Measurement   CHF Charging Equipment CSI-RS CSI   Function CPICHCommon Pilot Reference Signal   CI Cell Identity Channel CSI-RSRP CSI   CID Cell-ID (e.g., CQI Channel Quality reference signal   positioning method) Indicator received power   CIM Common CPU CSI processing unit, CSI-RSRQ CSI   Information Model Central Processing reference signal   CIR Carrier to Unit received quality   Interference Ratio C/R Command/Response CSI-SINR CSI signal-CK Cipher Key field bit to-noise and interference   CM Connection CRAN Cloud Radio Access ratio   Management, Conditional Network, Cloud CSMA Carrier Sense   Mandatory RAN Multiple Access   CMAS Commercial Mobile CRB Common Resource CSMA/CA CSMA with   Alert Service Block collision avoidance   CMD Command CRC Cyclic Redundancy CSS Common Search   CMS Cloud Management Check Space, Cell-specific   System CRI Channel-State Search Space   CO Conditional Information Resource CTF Charging   Optional Indicator, CSI-RS Trigger Function   CoMP Coordinated Multi-Resource Indicator CTS Clear-to-Send   Point C-RNTI Cell RNTI CW Codeword   CORESET Control CS Circuit Switched CWS Contention Window   Resource Set CSCF call session Size   COTS Commercial Off-control function D2D Device-to-Device   The-Shelf CSAR Cloud Service DC Dual Connectivity,   CP Control Plane, Archive Direct Current   Cyclic Prefix, Connection CSI Channel-State DCI Downlink Control   Point Information Information DF Deployment Flavour   DL Downlink ECCA extended clear EHE Edge   DMTF Distributed channel assessment, Hosting Environment   Management Task Force extended CCA EGMF Exposure   DPDK Data Plane ECCE Enhanced Control Governance Management   Development Kit Channel Element, Function   DM-RS, DMRS Enhanced CCE EGPRS Enhanced Demodulation ED Energy Detection GPRS   Reference Signal EDGE Enhanced Datarates EIR Equipment Identity   DN Data network for GSM Evolution Register   DNN Data Network (GSM Evolution) eLAA enhanced Licensed   Name EAS Edge Assisted Access,   DNAI Data Network Application Server enhanced LAA   Access Identifier EASID Edge EM Element Manager Application Server eMBB Enhanced Mobile   DRB Data Radio Bearer Identification Broadband   DRS Discovery ECS Edge EMS Element   Reference Signal Configuration Server Management System   DRX Discontinuous ECSP Edge eNB evolved NodeB, E-Reception Computing Service UTRAN Node B   DSL Domain Specific Provider EN-DC E-UTRA-NR   Language. Digital EDN Edge Data Dual Connectivity   Subscriber Line Network EPC Evolved Packet   DSLAM DSL Access EEC Edge Core   Multiplexer Enabler Client EPDCCH enhanced   DwPTS Downlink EECID Edge PDCCH, enhanced   Pilot Time Slot Enabler Client Physical Downlink   E-LAN Ethernet Identification Control Cannel   Local Area Network EES Edge EPRE Energy per resource   E2E End-to-End Enabler Server element   EAS Edge Application EESID Edge EPS Evolved Packet   Server Enabler Server System Identification   EREG enhanced REG, FACH Forward Access FQDN Fully Qualified   enhanced resource Channel Domain Name   element groups FAUSCH Fast Uplink G-RNTI GERAN   ETSI European Signalling Channel Radio Network Telecommunications FB Functional Block Temporary Identity Standards Institute FBI Feedback GERAN GSM EDGE   ETWS Earthquake and Information RAN, GSM EDGE Radio   Tsunami Warning FCC Federal Access Network   System Communications GGSN Gateway GPRS   eUICC embedded UICC, Commission Support Node   embedded Universal FCCH Frequency GLONASS GLObal&#39;naya   Integrated Circuit Card Correction CHannel NAvigatsionnaya   E-UTRA Evolved FDD Frequency Division Sputnikovaya   UTRA Duplex Sistema (Engl.:   E-UTRAN Evolved FDM Frequency Division Global Navigation   UTRAN Multiplex Satellite System)   EV2X Enhanced V2X FDMAFrequency Division gNB Next Generation   F1AP F1 Application Multiple Access NodeB   Protocol FE Front End gNB-CU gNB-F1-C F1 Control plane FEC Forward Error centralized unit, Next   interface Correction Generation NodeB   F1-U F1 User plane FFS For Further Study centralized unit   interface FFT Fast Fourier gNB-DU gNB-FACCH Fast Transformation distributed unit, Next   Associated Control feLAA further enhanced Generation NodeB CHannel Licensed Assisted distributed unit   FACCH/F Fast Access, further GNSS Global Navigation   Associated Control enhanced LAA Satellite System Channel/Full rate FN Frame Number GPRS General Packet   FACCH/H Fast FPGA Field-Programmable Radio Service   Associated Control Gate Array GPSI Generic Channel/Half rate FR Frequency Range Public Subscription Identifier   GSM Global System for HSN Hopping Sequence IEI Information Element Mobile Number Identifier Communications, HSPA High Speed Packet IEIDL Information Element   Groupe Spécial Access Identifier Data   Mobile HSS Home Subscriber Length   GTP GPRS Tunneling Server IETF Internet Engineering   Protocol HSUPA High Speed Task Force   GTP-UGPRS Tunnelling Uplink Packet Access IF Infrastructure   Protocol for User HTTP Hyper Text Transfer IIOT Industrial Internet of   Plane Protocol Things   GTS Go To Sleep Signal HTTPS Hyper Text IM Interference   (related to WUS) Transfer Protocol Measurement,   GUMMEI Globally Secure (https is Intermodulation, IP   Unique MME Identifier http/1.1 over SSL, Multimedia   GUTI Globally Unique i.e. port  443 ) IMC IMS Credentials   Temporary UE Identity I-Block Information IMEI International Mobile   HARQ Hybrid ARQ, Block Equipment Identity   Hybrid Automatic ICCID Integrated Circuit IMGI International mobile   Repeat Request Card Identification group identity   HANDO Handover IAB Integrated Access IMPI IP Multimedia   HFN HyperFrame and Backhaul Private Identity   Number ICIC Inter-Cell IMPU IP Multimedia   HHO Hard Handover Interference Coordination PUblic identity   HLR Home Location ID Identity, identifier IMS IP Multimedia   Register IDFT Inverse Discrete Subsystem   HN Home Network Fourier Transform IMSI International Mobile   HO Handover IE Information element Subscriber Identity   HPLMN Home Public IBE In-Band Emission IoT Internet of Things   Land Mobile Network IP Internet Protocol   HSDPA High Speed IEEE Institute of Ipsec IP Security, Internet   Downlink Packet Electrical and Electronics Protocol Security   Access Engineers   IP-CAN IP-Ki Individual LI Layer Indicator   Connectivity Access subscriber LLC Logical Link Network authentication key Control, Low Layer   IP-M IP Multicast KPI Key Performance Compatibility   IPv4 Internet Protocol Indicator LMF Location   Version 4 KQI Key Quality Management Function   IPv6 Internet Protocol Indicator LOS Line of Sight   Version 6 KSI Key Set Identifier LPLMN Local PLMN   IR Infrared ksps kilo-symbols per LPP LTE Positioning   IS In Sync second Protocol   IRP Integration KVM Kernel Virtual LSB Least Significant Bit   Reference Point Machine LTE Long Term   ISDN Integrated Services L1 Layer 1 (physical Evolution   Digital Network layer) LWA LTE-WLAN   ISIM IM Services Identity L1-RSRP Layer 1 aggregation   Module reference signal LWIP LTE/WLAN Radio   ISO International received power Level Integration with   Organisation for L2 Layer 2 (data link IPsec Tunnel   Standardisation layer) LTE Long Term   ISP Internet Service L3 Layer 3 (network Evolution   Provider layer) M2M Machine-to-IWF Interworking-LAA Licensed Assisted Machine   Function Access MAC Medium Access   I-WLAN Interworking LAN Local Area Network Control (protocol   WLAN LADN Local Area layering context) Constraint length of Data Network MAC Message   the convolutional code, LBT Listen Before Talk authentication code   USIM Individual key LCM LifeCycle (security/encryption   kB Kilobyte (1000 Management context)   bytes) LCR Low Chip Rate MAC-A MAC used   kbps kilo-bits per second LCS Location Services for authentication and   Kc Ciphering key LCID Logical key agreement (TSG T Channel ID WG3 context)   

     MAC-IMAC used for data MIB Master Information MPLS MultiProtocol Label
     integrity of signalling Block, Management Switching   messages (TSG T Information Base MS Mobile Station   WG3 context) MIMO Multiple Input MSB Most Significant Bit   MANO Management Multiple Output MSC Mobile Switching   and Orchestration MLC Mobile Location Centre   MBMS Multimedia Centre MSI Minimum System   Broadcast and Multicast MM Mobility Information, MCH   Service Management Scheduling   MB SFN Multimedia MME Mobility Information   Broadcast multicast Management Entity MSID Mobile Station   service Single Frequency MN Master Node Identifier   Network MNO Mobile MSIN Mobile Station   MCC Mobile Country Network Operator Identification   Code MO Measurement Number   MCG Master Cell Group Object, Mobile MSISDN Mobile   MCOTMaximum Channel Originated Subscriber ISDN Occupancy Time MPBCH MTC Number   MCS Modulation and Physical Broadcast MT Mobile Terminated,   coding scheme CHannel Mobile Termination   MDAF Management Data MPDCCH MTC MTC Machine-Type   Analytics Function Physical Downlink Communications   MDAS Management Data Control CHannel mMTCmassive MTC,   Analytics Service MPDSCH MTC massive Machine-MDT Minimization of Physical Downlink Type Communications   Drive Tests Shared CHannel MU-MIMO Multi User   ME Mobile Equipment MPRACH MTC MIMO   MeNB master eNB Physical Random MWUS MTC wake-MER Message Error Ratio Access CHannel up signal, MTC WUS   MGL Measurement Gap MPUSCH MTC NACK Negative   Length Physical Uplink Shared Acknowledgement   MGRP Measurement Gap Channel NAI Network Access Repetition Period Identifier   NAS Non-Access N-PoP Network Point of NS Network Service   Stratum, Non-Access Presence NSA Non-Standalone   Stratum layer NMIB, N-MIB Narrowband operation mode   NCT Network MIB NSD Network Service   Connectivity Topology NPBCH Narrowband Descriptor   NC-JT Non-Physical Broadcast NSR Network Service   Coherent Joint CHannel Record Transmission NPDCCH Narrowband NS SAINetwork Slice   NEC Network Capability Physical Downlink Selection Assistance Exposure Control CHannel Information   NE-DC NR-E-UTRA NPDSCH Narrowband S-NNSAI Single-Dual Connectivity Physical Downlink NSSAI   NEF Network Exposure Shared CHannel NSSF Network Slice Function NPRACH Narrowband Selection Function   NF Network Function Physical Random NW Network   NFP Network Access CHannel NWUSNarrowband wake-Forwarding Path NPUSCH Narrowband up signal, Narrowband   NFPD Network Physical Uplink WUS   Forwarding Path Shared CHannel NZP Non-Zero Power Descriptor NPSS Narrowband O&amp;M Operation and   NFV Network Functions Primary Maintenance Virtualization Synchronization ODU2 Optical channel   NFVI NFV Infrastructure Signal Data Unit-type 2   NFVO NFV Orchestrator NSSS Narrowband OFDM Orthogonal   NG Next Generation, Secondary Frequency Division   Next Gen Synchronization Multiplexing   NGEN-DC NG-RAN E-Signal OFDMA Orthogonal   UTRA-NR Dual NR New Radio, Frequency Division Connectivity Neighbour Relation Multiple Access   NM Network Manager NRF NF Repository OOB Out-of-band   NMS Network Function OOS Out of Sync   Management System NRS Narrowband OPEX OPerating EXpense Reference Signal   OSI Other System PDCCH Physical PNFR Physical Network   Information Downlink Control Function Record   OSS Operations Support Channel POC PTT over Cellular   System PDCP Packet Data PP, PTP Point-to-OTA over-the-air Convergence Protocol Point   PAPR Peak-to-Average PDN Packet Data PPP Point-to-Point   Power Ratio Network, Public Data Protocol   PAR Peak to Average Network PRACH Physical   Ratio PDSCH Physical RACH   PBCH Physical Broadcast Downlink Shared PRB Physical resource   Channel Channel block   PC Power Control, PDU Protocol Data Unit PRG Physical resource   Personal Computer PEI Permanent block group   PCC Primary Component Equipment Identifiers ProSe Proximity Services, Carrier, Primary CC PFD Packet Flow Proximity-Based   P-CSCF Proxy CSCF Description Service   PCell Primary Cell P-GW PDN Gateway PRS Positioning   PCI Physical Cell ID, PHICH Physical Reference Signal   Physical Cell Identity hybrid-ARQ indicator PRR Packet Reception   PCEF Policy and Charging channel Radio Enforcement PHY Physical layer PS Packet Services   Function PLMN Public Land Mobile PSBCH Physical   PCF Policy Control Network Sidelink Broadcast   Function PIN Personal Channel   PCRF Policy Control and Identification Number PSDCH Physical   Charging Rules PM Performance Sidelink Downlink   Function Measurement Channel   PDCP Packet Data PMI Precoding Matrix PSCCH Physical   Convergence Protocol, Indicator Sidelink Control   Packet Data Convergence PNF Physical Network Channel   Protocol layer Function PSSCH Physical PNFD Physical Network Sidelink Shared Function Descriptor Channel   PSCell Primary SCell RACH Random Access RLC UM RLC   PSS Primary Channel Unacknowledged Mode   Synchronization RADIUS Remote RLF Radio Link Failure Signal Authentication Dial In RLM Radio Link   PSTN Public Switched User Service Monitoring   Telephone Network RAN Radio Access RLM-RS Reference   PT-RS Phase-tracking Network Signal for RLM   reference signal RAND RANDom number RM Registration   PTT Push-to-Talk (used for Management   PUCCH Physical authentication) RMC Reference   Uplink Control RAR Random Access Measurement Channel Channel Response RMSI Remaining MSI,   PUSCH Physical RAT Radio Access Remaining Minimum   Uplink Shared Technology System Information Channel RAU Routing Area RN Relay Node   QAM Quadrature Update RNC Radio Network   Amplitude Modulation RB Resource block, Controller   QCI QoS class of Radio Bearer RNL Radio Network   identifier RBG Resource block Layer   QCL Quasi co-location group RNTI Radio Network   QFI QoS Flow ID, QoS REG Resource Element Temporary Identifier   Flow Identifier Group ROHC RObust Header   QoS Quality of Service Rel Release Compression   QPSK Quadrature REQ REQuest RRC Radio Resource   (Quaternary) Phase Shift RF Radio Frequency Control, Radio   Keying RI Rank Indicator Resource Control layer   QZSS Quasi-Zenith MV Resource indicator RRM Radio Resource   Satellite System value Management   RA-RNTI Random RL Radio Link RS Reference Signal   Access RNTI RLC Radio Link Control, RSRP Reference Signal   RAB Radio Access Radio Link Control layer Received Power   Bearer, Random RLC AM RLC RSRQ Reference Signal   Access Burst Acknowledged Mode Received Quality   RSSI Received Signal SAPI Service Access SDSF Structured Data   Strength Indicator Point Identifier Storage Function   RSU Road Side Unit SCC Secondary SDT Small Data   RSTD Reference Signal Component Carrier, Transmission   Time difference Secondary CC SDU Service Data Unit   RTP Real Time Protocol SCell Secondary Cell SEAF Security Anchor   RTS Ready-To-Send SCEF Service Function   RTT Round Trip Time Capability Exposure SeNB secondary eNB   Rx Reception, Function SEPP Security Edge   Receiving, Receiver SC-FDMA Single Protection Proxy   S1AP S1 Application Carrier Frequency SFI Slot format   Protocol Division Multiple indication   S1-MME S1 for the Access SFTD Space-Frequency   control plane SCG Secondary Cell Time Diversity, SFN and   S1-U S1 for the user plane Group frame timing difference   S-CSCF serving SCM Security Context SFN System Frame   CSCF Management Number   S-GW Serving Gateway SCS Subcarrier Spacing SgNB Secondary gNB   S-RNTI SRNC Radio SCTP Stream Control SGSN Serving GPRS   Network Temporary Transmission Support Node   Identity Protocol S-GW Serving Gateway   S-TMSI SAE SDAP Service Data SI System Information   Temporary Mobile Adaptation Protocol, SI-RNTI System Station Identifier Service Data Adaptation Information RNTI   SA Standalone Protocol layer SIB System Information   operation mode SDL Supplementary Block   SAE System Architecture Downlink SIM Subscriber Identity Evolution SDNF Structured Data Module   SAP Service Access Storage Network SIP Session Initiated   Point Function Protocol   SAPD Service Access SDP Session Description SiP System in Package   Point Descriptor Protocol SL Sidelink   SLA Service Level SSID Service Set SU-MIMO Single User   Agreement Identifier MIMO   SM Session SS/PBCH Block SUL Supplementary   Management SSBRI SS/PBCH Block Uplink   SMF Session Resource Indicator, TA Timing Advance,   Management Function Synchronization Tracking Area   SMS Short Message Signal Block TAC Tracking Area Code   Service Resource Indicator TAG Timing Advance   SMSF SMS Function SSC Session and Service Group   SMTC SSB-based Continuity TAI Tracking   Measurement Timing SS-RSRP Area Identity   Configuration Synchronization TAU Tracking Area   SN Secondary Node, Signal based Reference Update   Sequence Number Signal Received TB Transport Block   SoC System on Chip Power TBS Transport Block   SON Self-Organizing SS-RSRQ Size   Network Synchronization TBD To Be Defined   SpCell Special Cell Signal based Reference TCI Transmission   SP-CSI-RNTISemi-Signal Received Configuration Indicator   Persistent CSI RNTI Quality TCP Transmission   SPS Semi-Persistent SS-SINR Communication   Scheduling Synchronization Protocol   SQN Sequence number Signal based Signal to TDD Time Division   SR Scheduling Request Noise and Interference Duplex   SRB Signalling Radio Ratio TDM Time Division   Bearer SSS Secondary Multiplexing   SRS Sounding Reference Synchronization TDMATime Division   Signal Signal Multiple Access   SS Synchronization SSSG Search Space Set TE Terminal Equipment   Signal Group TEID Tunnel End Point   SSB Synchronization SSSIF Search Space Set Identifier   Signal Block Indicator TFT Traffic Flow SST Slice/Service Types Template   TMSI Temporary Mobile UDM Unified Data UTRAN Universal Subscriber Identity Management Terrestrial Radio   TNL Transport Network UDP User Datagram Access Network   Layer Protocol UwPTS Uplink Pilot   TPC Transmit Power UDSF Unstructured Data Time Slot   Control Storage Network V2I Vehicle-to-TPMI Transmitted Function Infrastruction   Precoding Matrix UICC Universal Integrated V2P Vehicle-to-Indicator Circuit Card Pedestrian   TR Technical Report UL Uplink V2V Vehicle-to-Vehicle   TRP, TRxP Transmission UM Unacknowledged V2X Vehicle-to-Reception Point Mode everything   TRS Tracking Reference UML Unified Modelling VIM Virtualized   Signal Language Infrastructure Manager   TRx Transceiver UMTS Universal Mobile VL Virtual Link,   TS Technical Telecommunications VLAN Virtual LAN,   Specifications, System Virtual Local Area Technical Standard UP User Plane Network   TTI Transmission Time UPF User Plane Function VM Virtual Machine   Interval URI Uniform Resource VNF Virtualized Network   Tx Transmission, Identifier Function Transmitting, URL Uniform Resource VNFFG VNF   Transmitter Locator Forwarding Graph   U-RNTI UTRAN URLLC Ultra-VNFFGD VNF   Radio Network Reliable and Low Forwarding Graph Temporary Identity Latency Descriptor   UART Universal USB Universal Serial Bus VNFM VNF Manager   Asynchronous USIM Universal VoIP Voice-over-IP, Receiver and Subscriber Identity Module Voice-over-Internet   Transmitter USS UE-specific search Protocol   UCI Uplink Control space VPLMN Visited   Information UTRA UMTS Terrestrial Public Land Mobile   UE User Equipment Radio Access Network   VPN Virtual Private   Network   VRB Virtual Resource   Block   WiMAX Worldwide   Interoperability for   Microwave Access   WLANWireless Local Area
       Network   
       WMAN Wireless   Metropolitan Area
       Network   
       WPANWireless Personal   Area Network   X2-C X2-Control plane   X2-U X2-User plane   XML eXtensible Markup
       Language   
       XRES EXpected user   RESponse   XOR eXclusive OR   ZC Zadoff-Chu   ZP Zero Power   

     Terminology 
     For the purposes of the present document, the following terms and definitions are applicable to the examples and embodiments discussed herein. 
     The term “circuitry” as used herein refers to, is part of, or includes hardware components such as an electronic circuit, a logic circuit, a processor (shared, dedicated, or group) and/or memory (shared, dedicated, or group), an Application Specific Integrated Circuit (ASIC), a field-programmable device (FPD) (e.g., a field-programmable gate array (FPGA), a programmable logic device (PLD), a complex PLD (CPLD), a high-capacity PLD (HCPLD), a structured ASIC, or a programmable SoC), digital signal processors (DSPs), etc., that are configured to provide the described functionality. In some embodiments, the circuitry may execute one or more software or firmware programs to provide at least some of the described functionality. The term “circuitry” may also refer to a combination of one or more hardware elements (or a combination of circuits used in an electrical or electronic system) with the program code used to carry out the functionality of that program code. In these embodiments, the combination of hardware elements and program code may be referred to as a particular type of circuitry. 
     The term “processor circuitry” as used herein refers to, is part of, or includes circuitry capable of sequentially and automatically carrying out a sequence of arithmetic or logical operations, or recording, storing, and/or transferring digital data. Processing circuitry may include one or more processing cores to execute instructions and one or more memory structures to store program and data information. The term “processor circuitry” may refer to one or more application processors, one or more baseband processors, a physical central processing unit (CPU), a single-core processor, a dual-core processor, a triple-core processor, a quad-core processor, and/or any other device capable of executing or otherwise operating computer-executable instructions, such as program code, software modules, and/or functional processes. Processing circuitry may include more hardware accelerators, which may be microprocessors, programmable processing devices, or the like. The one or more hardware accelerators may include, for example, computer vision (CV) and/or deep learning (DL) accelerators. The terms “application circuitry” and/or “baseband circuitry” may be considered synonymous to, and may be referred to as, “processor circuitry.” 
     The term “interface circuitry” as used herein refers to, is part of, or includes circuitry that enables the exchange of information between two or more components or devices. The term “interface circuitry” may refer to one or more hardware interfaces, for example, buses, I/O interfaces, peripheral component interfaces, network interface cards, and/or the like. 
     The term “user equipment” or “UE” as used herein refers to a device with radio communication capabilities and may describe a remote user of network resources in a communications network. The term “user equipment” or “UE” may be considered synonymous to, and may be referred to as, client, mobile, mobile device, mobile terminal, user terminal, mobile unit, mobile station, mobile user, subscriber, user, remote station, access agent, user agent, receiver, radio equipment, reconfigurable radio equipment, reconfigurable mobile device, etc. Furthermore, the term “user equipment” or “UE” may include any type of wireless/wired device or any computing device including a wireless communications interface. 
     The term “network element” as used herein refers to physical or virtualized equipment and/or infrastructure used to provide wired or wireless communication network services. The term “network element” may be considered synonymous to and/or referred to as a networked computer, networking hardware, network equipment, network node, router, switch, hub, bridge, radio network controller, RAN device, RAN node, gateway, server, virtualized VNF, NFVI, and/or the like. 
     The term “computer system” as used herein refers to any type interconnected electronic devices, computer devices, or components thereof. Additionally, the term “computer system” and/or “system” may refer to various components of a computer that are communicatively coupled with one another. Furthermore, the term “computer system” and/or “system” may refer to multiple computer devices and/or multiple computing systems that are communicatively coupled with one another and configured to share computing and/or networking resources. 
     The term “appliance,” “computer appliance,” or the like, as used herein refers to a computer device or computer system with program code (e.g., software or firmware) that is specifically designed to provide a specific computing resource. A “virtual appliance” is a virtual machine image to be implemented by a hypervisor-equipped device that virtualizes or emulates a computer appliance or otherwise is dedicated to provide a specific computing resource. 
     The term “resource” as used herein refers to a physical or virtual device, a physical or virtual component within a computing environment, and/or a physical or virtual component within a particular device, such as computer devices, mechanical devices, memory space, processor/CPU time, processor/CPU usage, processor and accelerator loads, hardware time or usage, electrical power, input/output operations, ports or network sockets, channel/link allocation, throughput, memory usage, storage, network, database and applications, workload units, and/or the like. A “hardware resource” may refer to compute, storage, and/or network resources provided by physical hardware element(s). A “virtualized resource” may refer to compute, storage, and/or network resources provided by virtualization infrastructure to an application, device, system, etc. The term “network resource” or “communication resource” may refer to resources that are accessible by computer devices/systems via a communications network. The term “system resources” may refer to any kind of shared entities to provide services, and may include computing and/or network resources. System resources may be considered as a set of coherent functions, network data objects or services, accessible through a server where such system resources reside on a single host or multiple hosts and are clearly identifiable. 
     The term “channel” as used herein refers to any transmission medium, either tangible or intangible, which is used to communicate data or a data stream. The term “channel” may be synonymous with and/or equivalent to “communications channel,” “data communications channel,” “transmission channel,” “data transmission channel,” “access channel,” “data access channel,” “link,” “data link,” “carrier,” “radiofrequency carrier,” and/or any other like term denoting a pathway or medium through which data is communicated. Additionally, the term “link” as used herein refers to a connection between two devices through a RAT for the purpose of transmitting and receiving information. 
     The terms “instantiate,” “instantiation,” and the like as used herein refers to the creation of an instance. An “instance” also refers to a concrete occurrence of an object, which may occur, for example, during execution of program code. 
     The terms “coupled,” “communicatively coupled,” along with derivatives thereof are used herein. The term “coupled” may mean two or more elements are in direct physical or electrical contact with one another, may mean that two or more elements indirectly contact each other but still cooperate or interact with each other, and/or may mean that one or more other elements are coupled or connected between the elements that are said to be coupled with each other. The term “directly coupled” may mean that two or more elements are in direct contact with one another. The term “communicatively coupled” may mean that two or more elements may be in contact with one another by a means of communication including through a wire or other interconnect connection, through a wireless communication channel or link, and/or the like. 
     The term “information element” refers to a structural element containing one or more fields. The term “field” refers to individual contents of an information element, or a data element that contains content. 
     The term “SMTC” refers to an SSB-based measurement timing configuration configured by SSB-MeasurementTimingConfiguration. 
     The term “SSB” refers to an SS/PBCH block. 
     The term “a “Primary Cell” refers to the MCG cell, operating on the primary frequency, in which the UE either performs the initial connection establishment procedure or initiates the connection re-establishment procedure. 
     The term “Primary SCG Cell” refers to the SCG cell in which the UE performs random access when performing the Reconfiguration with Sync procedure for DC operation. 
     The term “Secondary Cell” refers to a cell providing additional radio resources on top of a Special Cell for a UE configured with CA. 
     The term “Secondary Cell Group” refers to the subset of serving cells comprising the PSCell and zero or more secondary cells for a UE configured with DC. 
     The term “Serving Cell” refers to the primary cell for a UE in RRC_CONNECTED not configured with CA/DC there is only one serving cell comprising of the primary cell. 
     The term “serving cell” or “serving cells” refers to the set of cells comprising the Special Cell(s) and all secondary cells for a UE in RRC_CONNECTED configured with CA/. 
     The term “Special Cell” refers to the PCell of the MCG or the PSCell of the SCG for DC operation; otherwise, the term “Special Cell” refers to the Pcell.