PATENT DOCUMENT

Publication Number: US-11696187-B2
Application Number: US-202017442003-A
Country: US
Kind Code: B2

Title: Resource configuration in an integrated access and backhaul network

Abstract:
Disclosed are methods, systems, apparatus, and computer programs for communicating new link availability configurations for a node in an integrated access and backhaul (IAB) network. In one aspect, a method includes receiving a Radio Resource Control (RRC) message from an IAB node; determining, based on the RRC message, a new resource availability configuration for a backhaul resource associated with the IAB node; and in response to determining the new resource availability configuration, conditionally communicating with the IAB node over the backhaul resource according to the new resource availability configuration.

Claims:
What is claimed is: 
     
       1. A method comprising:
 receiving, from an integrated access and backhaul (TAB) central unit node, a Radio Resource Control (RRC) message that includes an uplink-downlink configuration setting; 
 determining, using at least in part the uplink-downlink configuration setting from the RRC message, a new resource availability configuration for a backhaul resource associated with the IAB central unit node, wherein the new resource availability configuration includes a hard resource availability bitmap having one or more first bits and a soft resource availability bitmap having one or more second different bits, wherein each bit in the hard resource availability bitmap and the soft resource availability bitmap corresponds to a different backhaul resource associated with the IAB central unit node; and 
 in response to determining the new resource availability configuration, conditionally communicating with the IAB central unit node over the backhaul resource according to the new resource availability configuration. 
 
     
     
       2. The method of  claim 1 , wherein the new resource availability configuration defines that the backhaul resource is hard available, and wherein communicating with the IAB central unit node over the backhaul resource according to the new resource availability configuration includes making the backhaul resource unconditionally available for transferring backhaul data. 
     
     
       3. The method of  claim 1 , wherein the new resource availability configuration defines that the backhaul resource is soft available, and wherein communicating with the IAB central unit node over the backhaul resource according to the new resource availability configuration includes making the backhaul resource conditionally available for transferring backhaul data. 
     
     
       4. The method of  claim 1 , wherein the new resource availability configuration defines that the backhaul resource is soft available, and wherein communicating with the IAB central unit node over the backhaul resource according to the new resource availability configuration includes making the backhaul resource unavailable for transferring backhaul data. 
     
     
       5. The method of  claim 1 , wherein a value of 1 in a bit in the hard resource availability bitmap indicates that the corresponding resource is unconditionally available for transferring backhaul data, and a value of 1 in a bit in the soft resource availability bitmap indicates that the corresponding resource is conditionally available for transferring backhaul data. 
     
     
       6. The method of  claim 5 , wherein a value of 0 in a bit in both the hard resource availability bitmap and the soft resource availability bitmap indicates that the corresponding resource is unavailable for transferring backhaul data. 
     
     
       7. The method of  claim 1 , wherein the backhaul resource includes one or more of: an uplink symbol, a downlink symbol, an uplink slot, or a downlink slot. 
     
     
       8. The method of  claim 1 , wherein the uplink-downlink configuration setting comprises a number of symbols in the new resource availability configuration that are either hard resources or soft resources. 
     
     
       9. The method of  claim 1 , comprising:
 determining, using at least in part a second new resource availability configuration for a second backhaul resource associated with the IAB central unit node that includes a first parameter that indicates that the backhaul resource should not be hard available and a second different parameter indicates that the backhaul resource should not be soft available, that the second backhaul resource should be unavailable for transferring backhaul data; and 
 in response to determining that the second backhaul resource should be unavailable for transferring backhaul data, making the second backhaul resource unavailable for transferring backhaul data. 
 
     
     
       10. A method comprising:
 determining, by an integrated access and backhaul (IAB) central unit node, a new resource availability configuration for a backhaul resource associated with an IAB node and a degree of availability of the backhaul resource; 
 generating, in response to determining that the new resource availability configuration that indicates that the backhaul resource is unavailable, a Radio Resource Control (RRC) message comprising the new resource availability configuration for the backhaul resource in an uplink-downlink configuration setting that includes a first parameter that indicates that the backhaul resource is not hard available and a second different parameter indicates that the backhaul resource is not soft available; and 
 transmitting the RRC message that includes the uplink-downlink configuration setting to the IAB node. 
 
     
     
       11. The method of  claim 10 , wherein the new resource availability configuration defines that a second backhaul resource is hard available, and wherein the new resource availability configuration directs the IAB node to make the second backhaul resource unconditionally available for transferring backhaul data. 
     
     
       12. The method of  claim 10 , wherein the new resource availability configuration defines that a second backhaul resource is soft available, and wherein the new resource availability configuration directs the IAB node to make the second backhaul resource conditionally available for transferring backhaul data. 
     
     
       13. The method of  claim 10 , wherein the new resource availability configuration defines that a second backhaul resource is unavailable, and wherein the new resource availability configuration directs the IAB node to make the second backhaul resource unavailable for transferring backhaul data. 
     
     
       14. The method of  claim 10 , wherein the new resource availability configuration includes a hard resource availability bitmap having one or more bits and a soft resource availability bitmap having one or more bits, wherein each bit in the hard resource availability bitmap and the soft resource availability bitmap corresponds to a different backhaul resource associated with the IAB node. 
     
     
       15. The method of  claim 14 , wherein a value of 1 in a bit in the hard resource availability bitmap indicates that the corresponding resource is unconditionally available for transferring backhaul data, and a value of 1 in a bit in the soft resource availability bitmap indicates that the corresponding resource is conditionally available for transferring backhaul data. 
     
     
       16. The method of  claim 15 , wherein a value of 0 in a bit in both the hard resource availability bitmap and the soft resource availability bitmap indicates that the corresponding resource is unavailable for transferring backhaul data. 
     
     
       17. The method of  claim 10 , wherein the backhaul resource includes one or more of: an uplink symbol, a downlink symbol, an uplink slot, or a downlink slot. 
     
     
       18. The method of  claim 10 , comprising communicating, at least in part in response to transmitting the RRC message that includes the uplink-downlink configuration setting to the IAB node, with the IAB node over the backhaul resource according to the new resource availability configuration. 
     
     
       19. An apparatus for an integrated access and backhaul (TAB) network comprising a non-transitory computer-readable storage device having stored thereon instructions, which, when executed by one or more processors, cause the one or more processors to perform operations comprising:
 receiving, from an TAB central unit node, a Radio Resource Control (RRC) message that includes an uplink-downlink configuration setting; 
 determining, using at least in part the uplink-downlink configuration setting from the RRC message, a new resource availability configuration for a backhaul resource associated with the TAB central unit node, wherein the new resource availability configuration includes a hard resource availability bitmap having one or more first bits and a soft resource availability bitmap having one or more second different bits, wherein each bit in the hard resource availability bitmap and the soft resource availability bitmap corresponds to a different backhaul resource associated with the TAB central unit node; and 
 in response to determining the new resource availability configuration, conditionally communicating with the TAB central unit node over the backhaul resource according to the new resource availability configuration. 
 
     
     
       20. The apparatus of  claim 19 , wherein the new resource availability configuration defines that the backhaul resource is hard available, and wherein communicating with the TAB central unit node over the backhaul resource according to the new resource availability configuration includes making the backhaul resource unconditionally available for transferring backhaul data.

Description:
CLAIM OF PRIORITY 
     The present application is a U.S. National Phase application under 35 U.S.C. § 371 of International Patent Application No. PCT/US2020/033255, filed on May 15, 2020, which claims priority to U.S. Provisional Patent Application No. 62/849,681 filed May 17, 2019, entitled “METHODS FOR RESOURCE CONFIGURATIONS IN RELAY NETWORK,” the disclosures of each of which are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND 
     User equipment (UE) can wirelessly communicate data using wireless communication networks. To wirelessly communicate data, the UE connects to a node of a radio access network (RAN) and synchronizes with the network. 
     SUMMARY 
     The present disclosure is directed towards methods, systems, apparatus, computer programs, or combinations thereof, for communicating new resource availability configurations to integrated access and backhaul (IAB) nodes. 
     In accordance with one aspect of the present disclosure, in an integrated access and backhaul (LAB) network, a method includes receiving a Radio Resource Control (RRC) message from an IAB node; determining, based on the RRC message, a new resource availability configuration for a backhaul resource associated with the IAB node; and in response to determining the new resource availability configuration, conditionally communicating with the IAB node over the backhaul resource according to the new resource availability configuration. 
     Other versions include corresponding systems, apparatus, and computer programs to perform the actions of methods defined by instructions encoded on computer readable storage devices. These and other versions may optionally include one or more of the following features. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is hard available, and wherein communicating with the IAB node over the backhaul resource according to the new resource availability configuration includes making the backhaul resource unconditionally available for transferring backhaul data. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is soft available, and wherein communicating with the IAB node over the backhaul resource according to the new resource availability configuration includes making the backhaul resource conditionally available for transferring backhaul data. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is soft available, and wherein communicating with the IAB node over the backhaul resource according to the new resource availability configuration includes making the backhaul resource unavailable for transferring backhaul data. 
     In some implementations, the new resource availability configuration includes a hard resource availability bitmap having one or more bits and a soft resource availability bitmap having one or more bits, wherein each bit in the hard resource availability bitmap and the soft resource availability bitmap corresponds to a different backhaul resource associated with the IAB node. 
     In some implementations, a value of 1 in a bit in the hard resource availability bitmap indicates that the corresponding resource is unconditionally available for transferring backhaul data, and a value of 1 in a bit in the soft resource availability bitmap indicates that the corresponding resource is conditionally available for transferring backhaul data. 
     In some implementations, a value of 0 in a bit in both the hard resource availability bitmap and the soft resource availability bitmap indicates that the corresponding resource is unavailable for transferring backhaul data. In some implementations, the backhaul resource includes one or more of: an uplink symbol, a downlink symbol, an uplink slot, or a downlink slot. 
     In accordance with another aspect of the present disclosure, in an integrated access and backhaul (IAB) network comprising an IAB node, a method includes determining a new resource availability configuration for a backhaul resource associated with the IAB node; generating, in response to new resource availability configuration, a message comprising the new resource availability configuration for the backhaul resource; and transmitting the message to the IAB node. 
     Other versions include corresponding systems, apparatus, and computer programs to perform the actions of methods defined by instructions encoded on computer readable storage devices. These and other versions may optionally include one or more of the following features. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is hard available, and wherein the new resource availability configuration directs the IAB node to make the backhaul resource unconditionally available for transferring backhaul data. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is soft available, and wherein the new resource availability configuration directs the IAB node to make the backhaul resource conditionally available for transferring backhaul data. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is unavailable, and wherein the new resource availability configuration directs the IAB node to make the backhaul resource unavailable for transferring backhaul data. 
     In some implementations, the new resource availability configuration includes a hard resource availability bitmap having one or more bits and a soft resource availability bitmap having one or more bits, wherein each bit in the hard resource availability bitmap and the soft resource availability bitmap corresponds to a different backhaul resource associated with the IAB node. 
     In some implementations, a value of 1 in a bit in the hard resource availability bitmap indicates that the corresponding resource is unconditionally available for transferring backhaul data, and a value of 1 in a bit in the soft resource availability bitmap indicates that the corresponding resource is conditionally available for transferring backhaul data. 
     In some implementations, a value of 0 in a bit in both the hard resource availability bitmap and the soft resource availability bitmap indicates that the corresponding resource is unavailable for transferring backhaul data. 
     In some implementations, the backhaul resource includes one or more of: an uplink symbol, a downlink symbol, an uplink slot, or a downlink slot. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG.  1    is an example integrated access and backhaul (IAB) network, according to some implementations of the present disclosure. 
         FIGS.  2 A and  2 B  each illustrate an example method, according to some implementations of the present disclosure. 
         FIG.  3    is an example architecture of a system of a network, according to some implementations of the present disclosure. 
         FIG.  4    illustrates an example architecture of a system including a CN, according to some implementations of the present disclosure. 
         FIG.  5    is a block diagram of an example of infrastructure equipment, according to some implementations of the present disclosure. 
         FIG.  6    is a block diagram of various protocol functions that may be implemented in a wireless communication device, according to some implementations of the present disclosure. 
         FIG.  7    is a block diagram illustrating components 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 described herein, according to some implementations of the present disclosure. 
     
    
    
     Like reference numbers and designations in the various drawings indicate like elements. 
     DETAILED DESCRIPTION 
     The present disclosure is related to Integrated Access and Backhaul (IAB) networks, which is a feature that enables multi-hop routing of data (e.g., as described in 3GPP Release 16 (Rel-16)). An architecture of IAB networks generally includes an IAB donor that serves a plurality of IAB nodes that operate as relays. The IAB donor is a network node (e.g., a base station) that terminates new generation (NG) interfaces. In particular, the IAB donor may serve as an interface for a user equipment (UE) to a core network and/or may provide wireless backhauling functionality to the plurality of IAB nodes. The plurality of IAB nodes can serve as access nodes to UEs and can provide backhaul links to other IAB nodes. 
     The IAB network architecture implements a central unit-distributed unit (CU-DU) split. In this architecture, the plurality of IAB nodes terminate the DU functionality, and the IAB donor terminates the CU functionality. Furthermore, each IAB node may include a Mobile Termination (MT) function. An IAB node may use the MT function to connect to a parent IAB node and/or the IAB donor. Further, the IAB node may use the DU function to communicate with UEs and/or MTs of child IAB nodes. Signaling between the MTs of IAB nodes or UEs and the CU of the IAB donor may use the Radio Resource Control (RRC) protocol. Signaling between the DUs of IAB nodes and the CU of the IAB donor may use an F1-AP protocol. 
     In an IAB network, an IAB node can be made aware of the semi-static distributed unit (DU) resource configuration (e.g., Downlink (DL), Uplink (UL), Flexible) of all its child IAB nodes. If the full DU resource configuration information of its child IAB nodes is not necessary, only the necessary configuration information may be signaled to the IAB node. Therefore semi-static resource allocation for IAB DU resource configuration can be configured by an IAB CU (central unit) in a centralized manner. On top of the DU DL, UL and Flexible pattern, the DU configuration of Hard, Soft and Not-available (H/S/NA) is also provided, which further indicates the availability of the configured DL/UL/Flexible resources as unconditionally available, conditionally available, or unavailable. Moreover, an explicit indication of availability of a Soft resource can be also used by the parent node to make the resource available to the child node, irrespective of the outcome of any implicit determination of availability by the child node. As a result, the parent node does not need to be aware of the outcome of an implicit determination of availability of a DU Soft resource at a child node. 
     Due to the fact that each of the D/U/F resource type may span over more than one slot in a “D-U-F” configuration sequence pattern, different signaling options of H/S/NA with different overheads lead to different trade-off among coordination flexibility and signaling overheads. 
     The present disclosure describes enhancements to the radio resource control (RRC) signaling protocol to enable an IAB-CU to flexibly configure coordinated resource availabilities (e.g., H/S/NA) to children IAB-DUs in an IAB network. The described techniques may enable the IAB-CU to configure resources of the IAB-DUs in the network, and to communicate the configuration in a data efficient manner. 
       FIG.  1    illustrates an example IAB network  100 , according to some implementations. As shown in  FIG.  1 A , IAB network  100  includes IAB-CU node  102 , and IAB-DU nodes  110 ,  120 . In the network  100 , IAB-CU node  102  is a central unit (CU) that controls the operation of one or more distributed units (DUs), such as IAB-DU nodes  110 ,  120 . For example, the IAB-CU node  102  may utilize the Radio Resource Control (RRC) protocol to control the operation of the IAB-DU nodes  110 ,  120 . IAB-CU node  102  is the parent node of IAB-DU nodes  110 ,  120 . Conversely, IAB-DU nodes  110 ,  120  are children of the IAB-CU node  102 . 
     In IAB network  100 , IAB-DU nodes  110 ,  120  may communicate with IAB-CU node  102  using backhaul (BH) resources  112 ,  122 . BH resources  112 ,  122  may be radio frequency (RF) resources used for data communication between the nodes. In some implementations, the IAB-DU nodes  110 ,  120  may communicate directly with each other or with other IAB-DU nodes over additional BH resources. 
     In IAB network  100 , each of the BH resources  112 ,  122  between the IAB-DU nodes  110 ,  120  and IAB-CU node  102  is associated with a resource availability (e.g., hard, soft, not available). For example, if BH resource  112  has a resource availability of “hard” (H), the resource is unconditionally available for backhaul data between the IAB-DU node  110  and the IAB-CU node  102 . If BH resource  112  has a resource availability of “soft” (S), the resource is conditionally available for backhaul data between the IAB node  110  and the IAB-CU node  102 . If BH resource  112  has a resource availability of “not available” (NA), the resource is not available for backhaul data between the IAB node  110  and the IAB-CU node  102 . In some implementations, the resource availability for the resources  112 ,  122  in the IAB network  100  can be configured by the IAB-CU node  102 . For example, the IAB-CU node  102  may send particular RRC information elements (IEs) including the resource configuration to the IAB-DU nodes  110 ,  120  to configure the availability of BH resources  112 ,  122 . 
     Disclosed are methods and systems for communicating resource availability configurations to IAB nodes in an IAB network (e.g., IAB network  100 ). The present techniques may enable an IAB-CU (e.g.,  102 ) to flexibly configure coordinated time resources to all children IAB-DUs (e.g.,  110 ,  120 ) in the IAB network  100 , which may enable the IAB network  100  to achieve greater data efficiency and better performance (e.g., data throughput). 
     In an embodiment, resource availability configuration, e.g., hard, soft or non-available (H/S/NA), which define the resource as unconditionally available, conditionally available and not available to IAB-DU, respectively, can be configured and signaled on slot level granularity. This can be realized by adding new parameters hardResourceSlotSet and softResourceSlotSet to TDD-UL-DL-Pattern information elements to be signaled from IAB-CU to IAB-DU via F1-AP signaling. A description the information element showing these new parameters is shown in Table 1, and a description of the parameters is shown in Table 2. 
     
       
         
           
               
             
               
                 TABLE 1 
               
               
                   
               
               
                 TDD-UL-DL-Pattern 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 TDD-UL-DL-Pattern ::=   SEQUENCE { 
               
               
                  dl-UL-TransmissionPeriodicity  ENUMERATED {ms0p5, ms0p625, 
               
               
                  ms1, ms1p25, ms2, ms2p5, ms5, ms10}, 
               
               
                  nrofDownlinkSlots    INTEGER (0..maxNrofSlots), 
               
               
                  nrofDownlinkSymbols    INTEGER (0..maxNrofSymbols−1), 
               
               
                  nrofUplinkSlots    INTEGER (0..maxNrofSlots), 
               
               
                  nrofUplinkSymbols    INTEGER (0..maxNrofSymbols−1), 
               
               
                  ..., 
               
               
                  [[ 
               
               
                  dl-UL-TransmissionPeriodicity-v1530  ENUMERATED {ms3, ms4} 
               
               
                 OPTIONAL -- Need R 
               
               
                  ]] 
               
               
                  dl-UL-Order  ENUMERATED {‘D-F-U’, ‘U-F-D’, ‘F-D-U’, ‘F-U-D’, 
               
               
                  ‘D-F-D&#39;, ‘U-F-U’}, 
               
               
                  hardResourceSlotSet BIT STRING (SIZE (1..maxNrSlotsInPattern)) 
               
               
                  OPTIONAL, 
               
               
                  softResourceSlotSet BIT STRING (SIZE (1..maxNrSlotsInPattern)) 
               
               
                  OPTIONAL 
               
               
                 } 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 2 
               
               
                   
               
               
                 TDD-UL-DL-Pattern field descriptions 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 DL-UL-Order: Defines the DL/UL/Flexible slots/symbols sequence order. 
               
               
                 hardResourceSlotSet: a bitmap indicating the set of slots in the pattern to be the 
               
               
                 hard resource, e.g., unconditionally available to IAB-DU. The first (left-most) bit in 
               
               
                 the bitmap corresponds to the first slot in the pattern and so on. If the bit is set to 1, 
               
               
                 the respective slot is configured as hard resource. 
               
               
                 softResourceSlotSet: a bitmap indicating the set of slots in the pattern to be the soft 
               
               
                 resource, e.g., conditionally available to IAB-DU. The first (left-most) bit in the 
               
               
                 bitmap corresponds to the first slot in the pattern and so on. If the bit is set to 1, the 
               
               
                 respective slot is configured as soft resource. 
               
               
                 maxNrSlotsInPattern: defines the maximum number of slots in the pattern, which 
               
               
                 can be set to a constant value, e.g., 640, or derived from dl-UL- 
               
               
                 TransmissionPeriodicity and referenceSubcarrierSpacing. 
               
               
                 The slots which have not been set as either hard or soft resources in two 
               
               
                 bitmaps, e.g., hardResourceSlotSet and softResourceSlotSet, shall be defined 
               
               
                 as non-available slots set. 
               
               
                 If the length of bitmaps signaling H/S slot set is fixed to a constant value, the 
               
               
                 valid length of the bitmaps is determined by the total slot number of the 
               
               
                 pattern which depends on dl-UL-TransmissionPeriodicity and 
               
               
                 referenceSubcarrierSpacing. 
               
               
                   
               
            
           
         
       
     
     In an embodiment, the resource availability configuration can be configured and signaled on symbol level granularity. This can be realized by adding new parameters hardResourceSymbolTSet and sofResourceSymbolSet to TDD-UL-DL-Pattern information elements to be signaled from IAB-CU to IAB-DU via F1-AP signaling. 
     A description the information element showing these new parameters is shown in Table 3, and a description of the parameters is shown in Table 4. 
     
       
         
           
               
             
               
                 TABLE 3 
               
               
                   
               
               
                 TDD-UL-DL-Pattern 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 TDD-UL-DL-Pattern ::=   SEQUENCE { 
               
               
                  dl-UL-TransmissionPeriodicity  ENUMERATED {ms0p5, ms0p625, 
               
               
                  ms1, ms1p25, ms2, ms2p5, ms5, ms10}, 
               
               
                  nrofDownlinkSlots   INTEGER (0..maxNrofSlots), 
               
               
                  nrofDownlinkSymbols   INTEGER (0..maxNrofSymbols−1), 
               
               
                  nrofUplinkSlots   INTEGER (0..maxNrofSlots), 
               
               
                  nrofUplinkSymbols   INTEGER (0..maxNrofSymbols−1), 
               
               
                   ..., 
               
               
                  [[ 
               
               
                  dl-UL-TransmissionPeriodicity-v1530  ENUMERATED {rns3, ms4} 
               
               
                 OPTIONAL -- Need R 
               
               
                  ]] 
               
               
                  dl-UL-Order ENUMERATED {‘D-F-U’, ‘U-F-D’, ‘F-D-U’, ‘F-U-D’, 
               
               
                  ‘D-F-D&#39;, ‘U-F-U’}, 
               
               
                  hardResourceSymbolSet  BIT STRING (SIZE 
               
               
                  (1..maxNrSymbolsInPattern)) OPTIONAL 
               
               
                  softResourceSymbolSet  BIT STRING (SIZE 
               
               
                  (1..maxNrSymbolsInPattern)) OPTIONAL 
               
               
                 } 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 4 
               
               
                   
               
               
                 TDD-UL-DL-Pattern field descriptions 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 DL-UL-Order: Defines the DL/UL/Flexible slots/symbols sequence order. 
               
               
                 hardResourceSymbolSet: a bitmap indicating the set of symbols in the pattern to be 
               
               
                 the hard resource, e.g., unconditionally available to IAB-DU. The first (left-most) 
               
               
                 bit in the bitmap corresponds to the first symbol in the pattern and so on. If the bit is 
               
               
                 set to 1, the respective symbol is configured as hard resource. 
               
               
                 softResourceSymbolSet: a bitmap indicating the set of symbols in the pattern to be 
               
               
                 the soft resource, e.g., conditionally available to IAB-DU. The first (left-most) bit in 
               
               
                 the bitmap corresponds to the first symbol in the pattern and so on. If the bit is set to 
               
               
                 1, the respective symbol is configured as soft resource. 
               
               
                 maxNrSymbolsInPattern: defines the maximum number of symbols in the pattern, 
               
               
                 which can be set to a constant value, e.g., 8960, or derived from dl-UL- 
               
               
                 TransmissionPeriodicity and referenceSubcarrierSpacing. 
               
               
                 The symbols which have not be set as either hard or soft resources in two 
               
               
                 bitmaps, e.g., hardResourceSymbol Set and softResourceSymbol Set, shall be 
               
               
                 defined as non-available symbols set. 
               
               
                 If the length of bitmaps signaling H/S symbol set is fixed to a constant value, 
               
               
                 the valid length of the bitmaps is determined by the total symbol number of 
               
               
                 the pattern which depends on dl-UL-TransmissionPeriodicity and 
               
               
                 referenceSubcarrierSpacing. 
               
               
                   
               
            
           
         
       
     
     In an embodiment, the resource availability configuration can be configured and signaled with configurable resource granularity. For example, the resource granularity can be slot, symbol, transmission direction and transmission direction per slot. This can be realized by adding new parameters resourceConfigGranularity to TDD-UL-DL-ConfigCommon, and hardResourceSet and softResourceSet to TDD-UL-DL-Pattern information elements (IEs) to be signaled from an IAB-CU to an IAB-DU via F1-AP signaling. 
     A description of these information elements and parameters are shown in Tables 5 through 8. 
     
       
         
           
               
             
               
                 TABLE 5 
               
               
                   
               
               
                 TDD-UL-DL-ConfigCommon 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 TDD-UL-DL-ConfigCommon ::=  SEQUENCE { 
               
               
                   referenceSubcarrierSpacing  SubcarrierSpacing, 
               
               
                   pattern1    TDD-UL-DL-Pattern, 
               
               
                   pattern2    TDD-UL-DL-Pattern OPTIONAL, -- Need R 
               
               
                   resourceConfigGranularity ENUMERATED {‘slot’, ‘symbol’, 
               
               
                   ‘transmissionDirection’, ‘transmissionDirectionAndSlot’}, 
               
               
                  ... 
               
               
                 } 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 6 
               
               
                   
               
               
                 TDD-UL-DL-ConfigCommon field descriptions 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 resourceConfigGranularity: defines the granularity of resource availability 
               
               
                 signaling in TDD-UL-DL-Pattern pattern1 and pattern2. The following granularity 
               
               
                 can be chosen: 
               
               
                 1. Slot level: when the granularity is set to ‘slot’, the signaled set of H/S/NA 
               
               
                 available resource is defined in terms of slot as in Method-1. 
               
               
                 2. Symbol level: when the granularity is set to ‘symbol’, the signaled set of 
               
               
                 H/S/NA available resource is defined in terms of symbol as in Method-2. 
               
               
                 3. Transmission direction level: when the granularity is set to 
               
               
                 ‘transmissionDirection’, the signaled set of H/S/NA available resource is 
               
               
                 defined in terms of transmission directions, e.g., DL, UL or flexible. 
               
               
                 4. Transmission direction and slot level: when the granularity is set to 
               
               
                 ‘transmissionDirectionAndSlot’, the signaled set of H/S/NA available 
               
               
                 resource is defined in terms of transmission directions per slot, e.g., 
               
               
                 DL/UL/Flexible per slot. 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 7 
               
               
                   
               
               
                 TDD-U-DL-Pattern 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 TDD-UL-DL-Pattern ::=  SEQUENCE { 
               
               
                  dl-UL-TransmissionPeriodicity  ENUMERATED {ms0p5, ms0p625, 
               
               
                  ms1, ms1p25, ms2, ms2p5, ms5, ms10}, 
               
               
                  nrofDownlinkSlots   INTEGER (0..maxNrofSlots), 
               
               
                  nrofDownlinkSymbols   INTEGER (0..maxNrofSymbols−1), 
               
               
                  nrofUplinkSlots   INTEGER (0..maxNrofSlots), 
               
               
                  nrofUplinkSymbols   INTEGER (0..maxNrofSymbols−1), 
               
               
                  ..., 
               
               
                  [[ 
               
               
                  dl-UL-TransmissionPeriodicity-v1530  ENUMERATED {ms3, ms4} 
               
               
                 OPTIONAL -- Need R 
               
               
                  ]] 
               
               
                  dl-UL-Order  ENUMERATED {‘D-F-U’, ‘U-F-D’, ‘F-D-U’, ‘F-U-D’, 
               
               
                  ‘D-F-D&#39;, ‘U-F-U’}, 
               
               
                  hardResourceSet  BIT STRING (SIZE (1..maxNrResourceSetsInPat- 
               
               
                  tern)) 
               
               
                  OPTIONAL, 
               
               
                  softResourceSet   BIT STRING (SIZE 
               
               
                  (1..maxNrResourceSetsInPattern)) OPTIONAL 
               
               
                 } 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 8 
               
               
                   
               
               
                 TDD-UL-DL-Pattern field descriptions 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 Dl-UL-Order: defines the DL/UL/Flexible slots/symbols sequence order. 
               
               
                 hardResourceSet: a bitmap indicating the set of resources, with the granularity 
               
               
                 defined by resourceConfigGranularity in TDD-UL-DL-ConfigCommon, in the 
               
               
                 pattern to be the hard resource, e.g., unconditionally available to IAB-DU. The first 
               
               
                 (left-most) bit in the bitmap corresponds to the first resource set with the granularity 
               
               
                 defined by resourceConfigGranularity in the pattern and so on. If the bit is set to 1, 
               
               
                 the respective resource set is configured as hard resource. 
               
               
                 softResourceSet: a bitmap indicating the set of resources, with the granularity 
               
               
                 defined by resourceConfigGranularity in TDD-UL-DL-ConfigCommon, in the 
               
               
                 pattern to be the soft resource, e.g., conditionally available to IAB-DU. The first 
               
               
                 (left-most) bit in the bitmap corresponds to the first resource set with the granularity 
               
               
                 defined by resourceConfigGranularity in the pattern and so on. If the bit is set to 1, 
               
               
                 the respective resource set is configured as soft resource. 
               
               
                 maxNrResourceSetsInPattern: defines the maximum number of resource sets in the 
               
               
                 pattern, which can be set to a constant value, e.g., 8960, or derived from dl-UL- 
               
               
                 TransmissionPeriodicity, referenceSubcarrierSpacing and 
               
               
                 resourceConfigGranularity. 
               
               
                 The resource sets which have not be set as either hard or soft resources in 
               
               
                 two bitmaps, e.g., hardResourceSet and softResourceSet, shall be defined as 
               
               
                 non-available resources set, 
               
               
                 If the length of bitmaps signaling H/S resource set is fixed to a constant 
               
               
                 value, the valid length of the bitmaps is determined by the total number of 
               
               
                 the resource sets in the pattern which depends on dl-UL- 
               
               
                 TransmissionPeriodicity, referenceSubcarrierSpacing and 
               
               
                 resourceConfigGranularity. 
               
               
                   
               
            
           
         
       
     
       FIGS.  2 A and  2 B  illustrate flowcharts of example processes, according to some implementations of the present disclosure. For clarity of presentation, the description that follows generally describes the processes in the context of the other figures in this description. As an example, process  200  can be performed by a base station (e.g., IAB donor) shown in  FIG.  1 A . As another example, process  210  can be performed by an IAB node shown in  FIG.  1 A . However, it will be understood that the processes may be performed, for example, by any suitable system, environment, software, and hardware, or a combination of systems, environments, software, and hardware, as appropriate. In some implementations, various steps of the processes can be run in parallel, in combination, in loops, or in any order. 
       FIG.  2 A  is a flowchart of an example process  200  for communicating new resource availability configurations to integrated access and backhaul (IAB) nodes. At step  202 , the process involves receiving a Radio Resource Control (RRC) message from an IAB node. In some implementations, the RRC message is received by an IAB-DU node (e.g,  110  in  FIG.  1   ), from an IAB-CU node (e.g.,  102 ). At step  204 , the process involves determining, based on the RRC message, a new resource availability configuration for a backhaul resource associated with the IAB node. At step  206 , the process involves, in response to determining the new resource availability configuration, conditionally communicating with the IAB node over the backhaul resource according to the new resource availability configuration. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is hard available, and wherein communicating with the IAB node over the backhaul resource according to the new resource availability configuration includes making the backhaul resource unconditionally available for transferring backhaul data. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is soft available, and wherein communicating with the TAB node over the backhaul resource according to the new resource availability configuration includes making the backhaul resource conditionally available for transferring backhaul data. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is soft available, and wherein communicating with the TAB node over the backhaul resource according to the new resource availability configuration includes making the backhaul resource unavailable for transferring backhaul data. 
     In some implementations, the new resource availability configuration includes a hard resource availability bitmap having one or more bits and a soft resource availability bitmap having one or more bits, wherein each bit in the hard resource availability bitmap and the soft resource availability bitmap corresponds to a different backhaul resource associated with the LAB node. 
     In some implementations, a value of 1 in a bit in the hard resource availability bitmap indicates that the corresponding resource is unconditionally available for transferring backhaul data, and a value of 1 in a bit in the soft resource availability bitmap indicates that the corresponding resource is conditionally available for transferring backhaul data. 
     In some implementations, a value of 0 in a bit in both the hard resource availability bitmap and the soft resource availability bitmap indicates that the corresponding resource is unavailable for transferring backhaul data. In some implementations, the backhaul resource includes one or more of: an uplink symbol, a downlink symbol, an uplink slot, or a downlink slot. 
       FIG.  2 B  is a flowchart of an example process  210 . At step  212 , the process involves determining a new resource availability configuration for a backhaul resource associated with the IAB node. At step  214 , the process involves generating, in response to new resource availability configuration, a message comprising the new resource availability configuration for the backhaul resource. At step  216 , the process involves transmitting the message to the IAB node. In some implementations, steps  212  through  216  are performed by an IAB-CU node (e.g,  102  in  FIG.  1   ), and the message is transmitted to an IAB-DU node (e.g.,  110 ). 
     In some implementations, the new resource availability configuration defines that the backhaul resource is hard available, and wherein the new resource availability configuration directs the IAB node to make the backhaul resource unconditionally available for transferring backhaul data. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is soft available, and wherein the new resource availability configuration directs the IAB node to make the backhaul resource conditionally available for transferring backhaul data. 
     In some implementations, the new resource availability configuration defines that the backhaul resource is unavailable, and wherein the new resource availability configuration directs the IAB node to make the backhaul resource unavailable for transferring backhaul data. 
     In some implementations, the new resource availability configuration includes a hard resource availability bitmap having one or more bits and a soft resource availability bitmap having one or more bits, wherein each bit in the hard resource availability bitmap and the soft resource availability bitmap corresponds to a different backhaul resource associated with the IAB node. 
     In some implementations, a value of 1 in a bit in the hard resource availability bitmap indicates that the corresponding resource is unconditionally available for transferring backhaul data, and a value of 1 in a bit in the soft resource availability bitmap indicates that the corresponding resource is conditionally available for transferring backhaul data. 
     In some implementations, a value of 0 in a bit in both the hard resource availability bitmap and the soft resource availability bitmap indicates that the corresponding resource is unavailable for transferring backhaul data. 
     In some implementations, the backhaul resource includes one or more of: an uplink symbol, a downlink symbol, an uplink slot, or a downlink slot. 
     The example processes shown in  FIGS.  2 A and  2 B  can be modified or reconfigured to include additional, fewer, or different steps (not shown in  FIGS.  2 A and  2 B ), which can be performed in the order shown or in a different order. 
       FIG.  3    illustrates an example architecture of a system  300  of a network, in accordance with various embodiments. The following description is provided for an example system  300  that operates in conjunction with the LTE system standards and 5G or NR system standards as provided by 3GPP technical specifications. 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 (e.g., Sixth Generation (6G)) systems, IEEE 802.16 protocols (e.g., WMAN, WiMAX, etc.), or the like. 
     As shown by  FIG.  3   , the system  300  includes UE  301   a  and UE  301   b  (collectively referred to as “UEs  301 ” or “UE  301 ”). In this example, UEs  301  are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks), but may also comprise any mobile or non-mobile computing device, such as consumer electronics devices, cellular phones, smartphones, feature phones, tablet computers, wearable computer devices, personal digital assistants (PDAs), pagers, wireless handsets, desktop computers, laptop computers, in-vehicle infotainment (IVI), in-car entertainment (ICE) devices, an Instrument Cluster (IC), head-up display (HUD) devices, onboard diagnostic (OBD) devices, dashtop mobile equipment (DME), mobile data terminals (MDTs), Electronic Engine Management System (EEMS), electronic/engine control units (ECUs), electronic/engine control modules (ECMs), embedded systems, microcontrollers, control modules, engine management systems (EMS), networked or “smart” appliances, MTC devices, M2M, IoT devices, and/or the like. 
     In some embodiments, any of the UEs  301  may be IoT UEs, which may comprise a network access layer designed for low-power IoT applications utilizing short-lived UE connections. An IoT UE can utilize technologies such as M2M or MTC for exchanging data with an MTC server or device via a PLMN, ProSe or D2D communication, sensor networks, or IoT networks. The M2M or MTC exchange of data may be a machine-initiated exchange of data. An IoT network describes interconnecting IoT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure), with short-lived connections. The IoT UEs may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate the connections of the IoT network. 
     The UEs  301  may be configured to connect, for example, communicatively couple, with a RAN  310 . In embodiments, the RAN  310  may be an NG RAN or a 5G RAN, an E-UTRAN, or a legacy RAN, such as a UTRAN or GERAN. As used herein, the term “NG RAN” or the like may refer to a RAN  310  that operates in an NR or 5G system  300 , and the term “E-UTRAN” or the like may refer to a RAN  310  that operates in an LTE or 4G system  300 . The UEs  301  utilize connections (or channels)  303  and  304 , respectively, each of which comprises a physical communications interface or layer (discussed in further detail below). 
     In this example, the connections  303  and  304  are illustrated as an air interface to enable communicative coupling, and can be consistent with cellular communications protocols, such as a GSM protocol, a CDMA network protocol, a PTT protocol, a POC protocol, a UMTS protocol, a 3GPP LTE protocol, a 5G protocol, a NR protocol, and/or any of the other communications protocols discussed herein. In embodiments, the UEs  301  may directly exchange communication data via a ProSe interface  305 . The ProSe interface  305  may alternatively be referred to as a SL interface  305  and may comprise one or more logical channels, including but not limited to a PSCCH, a PSSCH, a PSDCH, and a PSBCH. 
     The UE  301   b  is shown to be configured to access an AP  306  (also referred to as “WLAN node  306 ,” “WLAN  306 ,” “WLAN Termination  306 ,” “WT  306 ” or the like) via connection  307 . The connection  307  can comprise a local wireless connection, such as a connection consistent with any IEEE 802.11 protocol, wherein the AP  306  would comprise a wireless fidelity (Wi-Fi®) router. In this example, the AP  306  is shown to be connected to the Internet without connecting to the core network of the wireless system (described in further detail below). In various embodiments, the UE  301   b , RAN  310 , and AP  306  may be configured to utilize LWA operation and/or LWIP operation. The LWA operation may involve the UE  301   b  in RRC_CONNECTED being configured by a RAN node  311   a - b  to utilize radio resources of LTE and WLAN. LWIP operation may involve the UE  301   b  using WLAN radio resources (e.g., connection  307 ) via IPsec protocol tunneling to authenticate and encrypt packets (e.g., IP packets) sent over the connection  307 . IPsec tunneling may include encapsulating the entirety of original IP packets and adding a new packet header, thereby protecting the original header of the IP packets. 
     The RAN  310  can include one or more AN nodes or RAN nodes  311   a  and  311   b  (collectively referred to as “RAN nodes  311 ” or “RAN node  311 ”) that enable the connections  303  and  304 . As used herein, the terms “access node,” “access point,” or the like may describe equipment that provides the radio baseband functions for data and/or voice connectivity between a network and one or more users. These access nodes can be referred to as BS, gNBs, RAN nodes, eNBs, NodeBs, RSUs, TR×Ps or TRPs, and so forth, and can comprise ground stations (e.g., terrestrial access points) or satellite stations providing coverage within a geographic area (e.g., a cell). As used herein, the term “NG RAN node” or the like may refer to a RAN node  311  that operates in an NR or 5G system  300  (for example, a gNB), and the term “E-UTRAN node” or the like may refer to a RAN node  311  that operates in an LTE or 4G system  300  (e.g., an eNB). According to various embodiments, the RAN nodes  311  may be implemented as one or more of a dedicated physical device such as a macrocell base station, and/or a low power (LP) base station for providing femtocells, picocells or other like cells having smaller coverage areas, smaller user capacity, or higher bandwidth compared to macrocells. 
     In some embodiments, all or parts of the RAN nodes  311  may be implemented as one or more software entities running on server computers as part of a virtual network, which may be referred to as a CRAN and/or a virtual baseband unit pool (vBBUP). In these embodiments, the CRAN or vBBUP may implement a RAN function split, such as a PDCP split wherein RRC and PDCP layers are operated by the CRAN/vBBUP and other L2 protocol entities are operated by individual RAN nodes  311 ; a MAC/PHY split wherein RRC, PDCP, RLC, and MAC layers are operated by the CRAN/vBBUP and the PHY layer is operated by individual RAN nodes  311 ; or a “lower PHY” split wherein RRC, PDCP, RLC, MAC layers and upper portions of the PHY layer are operated by the CRAN/vBBUP and lower portions of the PHY layer are operated by individual RAN nodes  311 . This virtualized framework allows the freed-up processor cores of the RAN nodes  311  to perform other virtualized applications. In some implementations, an individual RAN node  311  may represent individual gNB-DUs that are connected to a gNB-CU via individual F1 interfaces (not shown by  FIG.  3   ). In these implementations, the gNB-DUs may include one or more remote radio heads or RFEMs (see, e.g.,  FIG.  5   ), and the gNB-CU may be operated by a server that is located in the RAN  310  (not shown) or by a server pool in a similar manner as the CRAN/vBBUP. Additionally or alternatively, one or more of the RAN nodes  311  may be next generation eNBs (ng-eNBs), which are RAN nodes that provide E-UTRA user plane and control plane protocol terminations toward the UEs  301 , and are connected to a 5GC via an NG interface (discussed infra). 
     In V2X scenarios one or more of the RAN nodes  311  may be or act as RSUs. The term “Road Side Unit” or “RSU” may refer to any transportation infrastructure entity used for V2X communications. An RSU may be implemented in or by a suitable RAN node or a stationary (or relatively stationary) UE, where an RSU implemented in or by a UE may be referred to as a “UE-type RSU,” an RSU implemented in or by an eNB may be referred to as an “eNB-type RSU,” an RSU implemented in or by a gNB may be referred to as a “gNB-type RSU,” and 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  301  (vUEs  301 ). 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 operate on the 5.9 GHz Direct Short Range Communications (DSRC) band to 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 operate on the cellular V2X band to provide the aforementioned low latency communications, as well as other cellular communications services. Additionally or alternatively, the RSU may operate as a Wi-Fi hotspot (2.4 GHz band) and/or provide connectivity to one or more cellular networks to provide uplink and downlink communications. The computing device(s) and some or all of the radiofrequency circuitry 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 and/or a backhaul network. 
     Any of the RAN nodes  311  can terminate the air interface protocol and can be the first point of contact for the UEs  301 . In some embodiments, any of the RAN nodes  311  can fulfill various logical functions for the RAN  310  including, but not limited to, radio network controller (RNC) functions such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. 
     In embodiments, the UEs  301  can be configured to communicate using OFDM communication signals with each other or with any of the RAN nodes  311  over a multicarrier communication channel in accordance with various communication techniques, such as, but not limited to, an OFDMA communication technique (e.g., for downlink communications) or a SC-FDMA communication technique (e.g., for uplink and ProSe or sidelink communications), although the scope of the embodiments is not limited in this respect. The OFDM signals can comprise a plurality of orthogonal subcarriers. 
     In some embodiments, a downlink resource grid can be used for downlink transmissions from any of the RAN nodes  311  to the UEs  301 , while uplink transmissions can utilize similar techniques. The grid can be a time-frequency grid, called a resource grid or time-frequency resource grid, which is the physical resource in the downlink in each slot. Such a time-frequency plane representation is a common practice for OFDM systems, which makes it intuitive for radio resource allocation. Each column and each row of the resource grid corresponds to one OFDM symbol and one OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to one slot in a radio frame. The smallest time-frequency unit in a resource grid is denoted as a resource element. Each resource grid comprises a number of resource blocks, which describe the mapping of certain physical channels to resource elements. Each resource block comprises a collection of resource elements; in the frequency domain, this may represent the smallest quantity of resources that currently can be allocated. There are several different physical downlink channels that are conveyed using such resource blocks. 
     According to various embodiments, the UEs  301  and the RAN nodes  311  communicate data (for example, transmit and receive) data over a licensed medium (also referred to as the “licensed spectrum” and/or the “licensed band”) and an unlicensed shared medium (also referred to as the “unlicensed spectrum” and/or the “unlicensed band”). The licensed spectrum may include channels that operate in the frequency range of approximately 400 MHz to approximately 3.8 GHz, whereas the unlicensed spectrum may include the 5 GHz band. 
     To operate in the unlicensed spectrum, the UEs  301  and the RAN nodes  311  may operate using LAA, eLAA, and/or feLAA mechanisms. In these implementations, the UEs  301  and the RAN nodes  311  may perform one or more known medium-sensing operations and/or carrier-sensing operations in order to determine whether one or more channels in the unlicensed spectrum is unavailable or otherwise occupied prior to transmitting in the unlicensed spectrum. The medium/carrier sensing operations may be performed according to a listen-before-talk (LBT) protocol. 
     LBT is a mechanism whereby equipment (for example, UEs  301  RAN nodes  311 , etc.) senses a medium (for example, a channel or carrier frequency) and transmits when the medium is sensed to be idle (or when a specific channel in the medium is sensed to be unoccupied). The medium sensing operation may include CCA, which utilizes at least ED to determine the presence or absence of other signals on a channel in order to determine if a channel is occupied or clear. This LBT mechanism allows cellular/LAA networks to coexist with incumbent systems in the unlicensed spectrum and with other LAA networks. ED may include sensing RF energy across an intended transmission band for a period of time and comparing the sensed RF energy to a predefined or configured threshold. 
     Typically, the incumbent systems in the 5 GHz band are WLANs based on IEEE 802.11 technologies. WLAN employs a contention-based channel access mechanism, called CSMA/CA. Here, when a WLAN node (e.g., a mobile station (MS) such as UE  301 , AP  306 , or the like) intends to transmit, the WLAN node may first perform CCA before transmission. Additionally, a backoff mechanism is used to avoid collisions in situations where more than one WLAN node senses the channel as idle and transmits at the same time. The backoff mechanism may be a counter that is drawn randomly within the CWS, which is increased exponentially upon the occurrence of collision and reset to a minimum value when the transmission succeeds. The LBT mechanism designed for LAA is somewhat similar to the CSMA/CA of WLAN. In some implementations, the LBT procedure for DL or UL transmission bursts including PDSCH or PUSCH transmissions, respectively, may have an LAA contention window that is variable in length between X and Y ECCA slots, where X and Y are minimum and maximum values for the CWSs for LAA. In one example, the minimum CWS for an LAA transmission may be 9 microseconds (μs); however, the size of the CWS and a MCOT (for example, a transmission burst) may be based on governmental regulatory requirements. 
     The LAA mechanisms are built upon CA technologies of LTE-Advanced systems. In CA, each aggregated carrier is referred to as a CC. A CC may have a bandwidth of 1.4, 3, 5, 10, 15 or 20 MHz and a maximum of five CCs can be aggregated, and therefore, a maximum aggregated bandwidth is 100 MHz. In FDD systems, the number of aggregated carriers can be different for DL and UL, where the number of UL CCs is equal to or lower than the number of DL component carriers. In some cases, individual CCs can have a different bandwidth than other CCs. In TDD systems, the number of CCs as well as the bandwidths of each CC is usually the same for DL and UL. 
     CA also comprises individual serving cells to provide individual CCs. The coverage of the serving cells may differ, for example, because CCs on different frequency bands will experience different pathloss. A primary service cell or PCell may provide a PCC for both UL and DL, and may handle RRC and NAS related activities. The other serving cells are referred to as SCells, and each SCell may provide an individual SCC for both UL and DL. The SCCs may be added and removed as required, while changing the PCC may require the UE  301  to undergo a handover. In LAA, eLAA, and feLAA, some or all of the SCells may operate in the unlicensed spectrum (referred to as “LAA SCells”), and the LAA SCells are assisted by a PCell operating in the licensed spectrum. When a UE is configured with more than one LAA SCell, the UE may receive UL grants on the configured LAA SCells indicating different PUSCH starting positions within a same subframe. 
     The PDSCH carries user data and higher-layer signaling to the UEs  301 . The PDCCH carries information about the transport format and resource allocations related to the PDSCH channel, among other things. It may also inform the UEs  301  about the transport format, resource allocation, and HARQ information related to the uplink shared channel. Typically, downlink scheduling (assigning control and shared channel resource blocks to the UE  301   b  within a cell) may be performed at any of the RAN nodes  311  based on channel quality information fed back from any of the UEs  301 . The downlink resource assignment information may be sent on the PDCCH used for (e.g., assigned to) each of the UEs  301 . 
     The PDCCH uses CCEs to convey the control information. Before being mapped to resource elements, the PDCCH complex-valued symbols may first be organized into quadruplets, which may then be permuted using a sub-block interleaver for rate matching. Each PDCCH may be transmitted using one or more of these CCEs, where each CCE may correspond to nine sets of four physical resource elements known as REGs. Four Quadrature Phase Shift Keying (QPSK) symbols may be mapped to each REG. The PDCCH can be transmitted using one or more CCEs, depending on the size of the DCI and the channel condition. There can be four or more different PDCCH formats defined in LTE with different numbers of CCEs (e.g., aggregation level, L=1, 2, 4, or 8). 
     Some embodiments may use concepts for resource allocation for control channel information that are an extension of the above-described concepts. For example, some embodiments may utilize an EPDCCH that uses PDSCH resources for control information transmission. The EPDCCH may be transmitted using one or more ECCEs. Similar to above, each ECCE may correspond to nine sets of four physical resource elements known as an EREGs. An ECCE may have other numbers of EREGs in some situations. 
     The RAN nodes  311  may be configured to communicate with one another via interface  312 . In embodiments where the system  300  is an LTE system (e.g., when CN  320  is an EPC  420  as in  FIG.  4   ), the interface  312  may be an X2 interface  312 . The X2 interface may be defined between two or more RAN nodes  311  (e.g., two or more eNBs and the like) that connect to EPC  320 , and/or between two eNBs connecting to EPC  320 . In some implementations, the X2 interface may include an X2 user plane interface (X2-U) and an X2 control plane interface (X2-C). The X2-U may provide flow control mechanisms for user data packets transferred over the X2 interface, and may be used to communicate information about the delivery of user data between eNBs. For example, the X2-U may provide specific sequence number information for user data transferred from a MeNB to an SeNB; information about successful in sequence delivery of PDCP PDUs to a UE  301  from an SeNB for user data; information of PDCP PDUs that were not delivered to a UE  301 ; information about a current minimum desired buffer size at the SeNB for transmitting to the UE user data; and the like. The X2-C may provide intra-LTE access mobility functionality, including context transfers from source to target eNBs, user plane transport control, etc.; load management functionality; as well as inter-cell interference coordination functionality. 
     In embodiments where the system  300  is a 5G or NR system, the interface  312  may be an Xn interface  312 . The Xn interface is defined between two or more RAN nodes  311  (e.g., two or more gNBs and the like) that connect to 5GC  320 , between a RAN node  311  (e.g., a gNB) connecting to 5GC  320  and an eNB, and/or between two eNBs connecting to 5GC  320 . In some implementations, the Xn interface may include an Xn user plane (Xn-U) interface and an Xn control plane (Xn-C) interface. The Xn-U may provide non-guaranteed delivery of user plane PDUs and support/provide data forwarding and flow control functionality. The Xn-C may provide management and error handling functionality, functionality to manage the Xn-C interface; mobility support for UE  301  in a connected mode (e.g., CM-CONNECTED) including functionality to manage the UE mobility for connected mode between one or more RAN nodes  311 . The mobility support may include context transfer from an old (source) serving RAN node  311  to new (target) serving RAN node  311 ; and control of user plane tunnels between old (source) serving RAN node  311  to new (target) serving RAN node  311 . A protocol stack of the Xn-U may include a transport network layer built on Internet Protocol (IP) transport layer, and a GTP-U layer on top of a UDP and/or IP layer(s) to carry user plane PDUs. The Xn-C protocol stack may include an application layer signaling protocol (referred to as Xn Application Protocol (Xn-AP)) and a transport network layer that is built on SCTP. The SCTP may be on top of an IP layer, and may provide the guaranteed delivery of application layer messages. In the transport IP layer, point-to-point transmission is used to deliver the signaling PDUs. In other implementations, the Xn-U protocol stack and/or the Xn-C protocol stack may be same or similar to the user plane and/or control plane protocol stack(s) shown and described herein. 
     The RAN  310  is shown to be communicatively coupled to a core network—in this embodiment, core network (CN)  320 . The CN  320  may comprise a plurality of network elements  322 , which are configured to offer various data and telecommunications services to customers/subscribers (e.g., users of UEs  301 ) who are connected to the CN  320  via the RAN  310 . The components of the CN  320  may be implemented in one physical node or separate physical nodes including components to read and execute instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium). In some embodiments, NFV may be utilized to virtualize any or all of the above-described network node functions via executable instructions stored in one or more computer-readable storage mediums (described in further detail below). 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. NFV architectures and infrastructures may be used to virtualize one or more network functions, alternatively performed by proprietary hardware, onto physical resources comprising a combination of industry-standard server hardware, storage hardware, or switches. In other words, NFV systems can be used to execute virtual or reconfigurable implementations of one or more EPC components/functions. 
     Generally, the application server  330  may be an element offering applications that use IP bearer resources with the core network (e.g., UMTS PS domain, LTE PS data services, etc.). The application server  330  can also be configured to support one or more communication services (e.g., VoIP sessions, PTT sessions, group communication sessions, social networking services, etc.) for the UEs  301  via the EPC  320 . 
     In embodiments, the CN  320  may be a 5GC (referred to as “5GC  320 ” or the like), and the RAN  310  may be connected with the CN  320  via an NG interface  313 . In embodiments, the NG interface  313  may be split into two parts, an NG user plane (NG-U) interface  314 , which carries traffic data between the RAN nodes  311  and a UPF, and the S1 control plane (NG-C) interface  315 , which is a signaling interface between the RAN nodes  311  and AMFs. 
     In embodiments, the CN  320  may be a 5G CN (referred to as “5GC  320 ” or the like), while in other embodiments, the CN  320  may be an EPC). Where CN  320  is an EPC (referred to as “EPC  320 ” or the like), the RAN  310  may be connected with the CN  320  via an S1 interface  313 . In embodiments, the S1 interface  313  may be split into two parts, an S1 user plane (S1-U) interface  314 , which carries traffic data between the RAN nodes  311  and the S-GW, and the S1-MME interface  315 , which is a signaling interface between the RAN nodes  311  and MMEs. 
       FIG.  4    illustrates an example architecture of a system  400  including a first CN  420 , in accordance with various embodiments. In this example, system  400  may implement the LTE standard wherein the CN  420  is an EPC  420  that corresponds with CN  320  of  FIG.  3   . Additionally, the UE  401  may be the same or similar as the UEs  301  of  FIG.  3   , and the E-UTRAN  410  may be a RAN that is the same or similar to the RAN  310  of  FIG.  3   , and which may include RAN nodes  311  discussed previously. The CN  420  may comprise MMEs  421 , an S-GW  422 , a P-GW  423 , a HSS  424 , and a SGSN  425 . 
     The MMEs  421  may be similar in function to the control plane of legacy SGSN, and may implement MM functions to keep track of the current location of a UE  401 . The MMEs  421  may perform various MM procedures to manage mobility aspects in access such as gateway selection and tracking area list management. MM (also referred to as “EPS MM” or “EMM” in E-UTRAN systems) may refer to all applicable procedures, methods, data storage, etc. that are used to maintain knowledge about a present location of the UE  401 , provide user identity confidentiality, and/or perform other like services to users/subscribers. Each UE  401  and the MME  421  may include an MM or EMM sublayer, and an MM context may be established in the UE  401  and the MME  421  when an attach procedure is successfully completed. The MM context may be a data structure or database object that stores MM-related information of the UE  401 . The MMEs  421  may be coupled with the HSS  424  via an S6a reference point, coupled with the SGSN  425  via an S3 reference point, and coupled with the S-GW  422  via an S11 reference point. 
     The SGSN  425  may be a node that serves the UE  401  by tracking the location of an individual UE  401  and performing security functions. In addition, the SGSN  425  may perform Inter-EPC node signaling for mobility between 2G/3G and E-UTRAN 3GPP access networks; PDN and S-GW selection as specified by the MMEs  421 ; handling of UE  401  time zone functions as specified by the MMEs  421 ; and MME selection for handovers to E-UTRAN 3GPP access network. The S3 reference point between the MMEs  421  and the SGSN  425  may enable user and bearer information exchange for inter-3GPP access network mobility in idle and/or active states. 
     The HSS  424  may comprise a database for network users, including subscription-related information to support the network entities&#39; handling of communication sessions. The EPC  420  may comprise one or several HSSs  424 , depending on the number of mobile subscribers, on the capacity of the equipment, on the organization of the network, etc. For example, the HSS  424  can provide support for routing/roaming, authentication, authorization, naming/addressing resolution, location dependencies, etc. An S6a reference point between the HSS  424  and the MMEs  421  may enable transfer of subscription and authentication data for authenticating/authorizing user access to the EPC  420  between HSS  424  and the MMEs  421 . 
     The S-GW  422  may terminate the S1 interface  313  (“S1-U” in  FIG.  4   ) toward the RAN  410 , and routes data packets between the RAN  410  and the EPC  420 . In addition, the S-GW  422  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 S11 reference point between the S-GW  422  and the MMEs  421  may provide a control plane between the MMEs  421  and the S-GW  422 . The S-GW  422  may be coupled with the P-GW  423  via an S5 reference point. 
     The P-GW  423  may terminate an SGi interface toward a PDN  430 . The P-GW  423  may route data packets between the EPC  420  and external networks such as a network including the application server  330  (alternatively referred to as an “AF”) via an IP interface  325  (see e.g.,  FIG.  3   ). In embodiments, the P-GW  423  may be communicatively coupled to an application server (application server  330  of  FIG.  3    or PDN  430  in  FIG.  4   ) via an IP communications interface  325  (see, e.g.,  FIG.  3   ). The S5 reference point between the P-GW  423  and the S-GW  422  may provide user plane tunneling and tunnel management between the P-GW  423  and the S-GW  422 . The S5 reference point may also be used for S-GW  422  relocation due to UE  401  mobility and if the S-GW  422  needs to connect to a non-collocated P-GW  423  for the required PDN connectivity. The P-GW  423  may further include a node for policy enforcement and charging data collection (e.g., PCEF (not shown)). Additionally, the SGi reference point between the P-GW  423  and the packet data network (PDN)  430  may be an operator external public, a private PDN, or an intra operator packet data network, for example, for provision of MS services. The P-GW  423  may be coupled with a PCRF  426  via a Gx reference point. 
     PCRF  426  is the policy and charging control element of the EPC  420 . In a non-roaming scenario, there may be a single PCRF  426  in the Home Public Land Mobile Network (HPLMN) associated with a UE  401 &#39;s Internet Protocol Connectivity Access Network (IP-CAN) session. In a roaming scenario with local breakout of traffic, there may be two PCRFs associated with a UE  401 &#39;s IP-CAN session, a Home PCRF (H-PCRF) within an HPLMN and a Visited PCRF (V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF  426  may be communicatively coupled to the application server  430  via the P-GW  423 . The application server  430  may signal the PCRF  426  to indicate a new service flow and select the appropriate QoS and charging parameters. The PCRF  426  may provision this rule into a PCEF (not shown) with the appropriate TFT and QCI, which commences the QoS and charging as specified by the application server  430 . The Gx reference point between the PCRF  426  and the P-GW  423  may allow for the transfer of QoS policy and charging rules from the PCRF  426  to PCEF in the P-GW  423 . An Rx reference point may reside between the PDN  430  (or “AF  430 ”) and the PCRF  426 . 
       FIG.  5    illustrates an example of infrastructure equipment  500  in accordance with various embodiments. The infrastructure equipment  500  (or “system  500 ”) may be implemented as a base station, radio head, RAN node such as the RAN nodes  311  and/or AP  306  shown and described previously, application server(s)  330 , and/or any other element/device discussed herein. In other examples, the system  500  could be implemented in or by a UE. 
     The system  500  includes application circuitry  505 , baseband circuitry  510 , one or more radio front end modules (RFEMs)  515 , memory circuitry  520 , power management integrated circuitry (PMIC)  525 , power tee circuitry  530 , network controller circuitry  535 , network interface connector  540 , satellite positioning circuitry  545 , and user interface circuitry  550 . In some embodiments, the device  500  may include additional elements such as, for example, memory/storage, display, camera, sensor, or input/output (I/O) interface. In other embodiments, the components described below may be included in more than one device. For example, said circuitries may be separately included in more than one device for CRAN, vBBU, or other like implementations. 
     Application circuitry  505  includes circuitry such as, but not limited to one or more processors (or processor cores), cache memory, and one or more of low drop-out voltage regulators (LDOs), interrupt controllers, serial interfaces such as SPI, I2C or universal programmable serial interface module, real time clock (RTC), timer-counters including interval and watchdog timers, general purpose input/output (I/O or IO), memory card controllers such as Secure Digital (SD) MultiMediaCard (MMC) or similar, Universal Serial Bus (USB) interfaces, Mobile Industry Processor Interface (MIPI) interfaces and Joint Test Access Group (JTAG) test access ports. The processors (or cores) of the application circuitry  505  may be coupled with or may include memory/storage elements and may be configured to execute instructions stored in the memory/storage to enable various applications or operating systems to run on the system  500 . In some implementations, the memory/storage elements may be on-chip memory circuitry, which may include any suitable volatile and/or non-volatile memory, such as DRAM, SRAM, EPROM, EEPROM, Flash memory, solid-state memory, and/or any other type of memory device technology, such as those discussed herein. 
     The processor(s) of application circuitry  505  may include, for example, one or more processor cores (CPUs), one or more application processors, one or more graphics processing units (GPUs), one or more reduced instruction set computing (RISC) processors, one or more Acorn RISC Machine (ARM) processors, one or more complex instruction set computing (CISC) processors, one or more digital signal processors (DSP), one or more FPGAs, one or more PLDs, one or more ASICs, one or more microprocessors or controllers, or any suitable combination thereof. In some embodiments, the application circuitry  505  may comprise, or may be, a special-purpose processor/controller to operate according to the various embodiments herein. As examples, the processor(s) of application circuitry  505  may include one or more Apple A-series processors, Intel Pentium®, Core®, or Xeon® processor(s); Advanced Micro Devices (AMD) Ryzen® processor(s), Accelerated Processing Units (APUs), or Epyc® processors; ARM-based processor(s) licensed from ARM Holdings, Ltd. such as the ARM Cortex-A family of processors and the ThunderX2® provided by Cavium™, Inc.; a MIPS-based design from MIPS Technologies, Inc. such as MIPS Warrior P-class processors, and/or the like. In some embodiments, the system  500  may not utilize application circuitry  505 , and instead may include a special-purpose processor/controller to process IP data received from an EPC or 5GC, for example. 
     In some implementations, the application circuitry  505  may include one or 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. As examples, the programmable processing devices may be one or more a field-programmable devices (FPDs) such as field-programmable gate arrays (FPGAs) and the like; programmable logic devices (PLDs) such as complex PLDs (CPLDs), high-capacity PLDs (HCPLDs), and the like; ASICs such as structured ASICs and the like; programmable SoCs (PSoCs); and the like. In such implementations, the circuitry of application circuitry  505  may comprise logic blocks or logic fabric, and other interconnected resources that may be programmed to perform various functions, such as the procedures, methods, functions, etc. of the various embodiments discussed herein. In such embodiments, the circuitry of application circuitry  505  may include memory cells (e.g., erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, static memory (e.g., static random access memory (SRAM), anti-fuses, etc.)) used to store logic blocks, logic fabric, data, etc. in look-up-tables (LUTs) and the like. 
     The baseband circuitry  510  may be implemented, for example, as a solder-down substrate including one or more integrated circuits, a single packaged integrated circuit soldered to a main circuit board or a multi-chip module containing two or more integrated circuits. 
     User interface circuitry  550  may include one or more user interfaces designed to enable user interaction with the system  500  or peripheral component interfaces designed to enable peripheral component interaction with the system  500 . User interfaces may include, but are not limited to, one or more physical or virtual buttons (e.g., a reset button), one or more indicators (e.g., light emitting diodes (LEDs)), a physical keyboard or keypad, a mouse, a touchpad, a touchscreen, speakers or other audio emitting devices, microphones, a printer, a scanner, a headset, a display screen or display device, etc. Peripheral component interfaces may include, but are not limited to, a nonvolatile memory port, a universal serial bus (USB) port, an audio jack, a power supply interface, etc. 
     The radio front end modules (RFEMs)  515  may comprise a millimeter wave (mmWave) RFEM and one or more sub-mmWave radio frequency integrated circuits (RFICs). In some implementations, the one or more sub-mmWave RFICs may be physically separated from the mmWave RFEM. The RFICs may include connections to one or more antennas or antenna arrays, and the RFEM may be connected to multiple antennas. In alternative implementations, both mmWave and sub-mmWave radio functions may be implemented in the same physical RFEM  515 , which incorporates both mmWave antennas and sub-mmWave. 
     The memory circuitry  520  may include one or more of volatile memory including dynamic random access memory (DRAM) and/or synchronous dynamic random access memory (SDRAM), and nonvolatile memory (NVM) including high-speed electrically erasable memory (commonly referred to as Flash memory), phase change random access memory (PRAM), magnetoresistive random access memory (MRAM), etc., and may incorporate the three-dimensional (3D) cross-point (XPOINT) memories from Intel® and Micron®. Memory circuitry  520  may be implemented as one or more of solder down packaged integrated circuits, socketed memory modules and plug-in memory cards. 
     The PMIC  525  may include voltage regulators, surge protectors, power alarm detection circuitry, and one or more backup power sources such as a battery or capacitor. The power alarm detection circuitry may detect one or more of brown out (under-voltage) and surge (over-voltage) conditions. The power tee circuitry  530  may provide for electrical power drawn from a network cable to provide both power supply and data connectivity to the infrastructure equipment  500  using a single cable. 
     The network controller circuitry  535  may provide connectivity to a network using a standard network interface protocol such as Ethernet, Ethernet over GRE Tunnels, Ethernet over Multiprotocol Label Switching (MPLS), or some other suitable protocol. Network connectivity may be provided to/from the infrastructure equipment  500  via network interface connector  540  using a physical connection, which may be electrical (commonly referred to as a “copper interconnect”), optical, or wireless. The network controller circuitry  535  may include one or more dedicated processors and/or FPGAs to communicate using one or more of the aforementioned protocols. In some implementations, the network controller circuitry  535  may include multiple controllers to provide connectivity to other networks using the same or different protocols. 
     The positioning circuitry  545  includes circuitry to receive and decode signals transmitted/broadcasted by a positioning network of a global navigation satellite system (GNSS). Examples of navigation satellite constellations (or GNSS) include United States&#39; Global Positioning System (GPS), Russia&#39;s Global Navigation System (GLONASS), the European Union&#39;s Galileo system, China&#39;s BeiDou Navigation Satellite System, a regional navigation system or GNSS augmentation system (e.g., Navigation with Indian Constellation (NAVIC), Japan&#39;s Quasi-Zenith Satellite System (QZSS), France&#39;s Doppler Orbitography and Radio-positioning Integrated by Satellite (DORIS), etc.), or the like. The positioning circuitry  545  comprises various hardware elements (e.g., including hardware devices such as switches, filters, amplifiers, antenna elements, and the like to facilitate OTA communications) to communicate with components of a positioning network, such as navigation satellite constellation nodes. In some embodiments, the positioning circuitry  545  may include a Micro-Technology for Positioning, Navigation, and Timing (Micro-PNT) IC that uses a master timing clock to perform position tracking/estimation without GNSS assistance. The positioning circuitry  545  may also be part of, or interact with, the baseband circuitry  510  and/or RFEMs  515  to communicate with the nodes and components of the positioning network. The positioning circuitry  545  may also provide position data and/or time data to the application circuitry  505 , which may use the data to synchronize operations with various infrastructure (e.g., RAN nodes  311 , etc.), or the like. 
     The components shown by  FIG.  5    may communicate with one another using interface circuitry, which may include any number of bus and/or interconnect (IX) technologies such as industry standard architecture (ISA), extended ISA (EISA), peripheral component interconnect (PCI), peripheral component interconnect extended (PCIx), PCI express (PCIe), or any number of other technologies. The bus/IX may be a proprietary bus, for example, used in a SoC based system. Other bus/IX systems may be included, such as an I2C interface, an SPI interface, point to point interfaces, and a power bus, among others. 
       FIG.  6    illustrates various protocol functions that may be implemented in a wireless communication device according to various embodiments. In particular,  FIG.  6    includes an arrangement  600  showing interconnections between various protocol layers/entities. The following description of  FIG.  6    is provided for various protocol layers/entities that operate in conjunction with the 5G/NR system standards and LTE system standards, but some or all of the aspects of  FIG.  6    may be applicable to other wireless communication network systems as well. 
     The protocol layers of arrangement  600  may include one or more of PHY  610 , MAC  620 , RLC  630 , PDCP  640 , SDAP  647 , RRC  655 , and NAS layer  657 , in addition to other higher layer functions not illustrated. The protocol layers may include one or more service access points (e.g., items  659 ,  656 ,  650 ,  649 ,  645 ,  635 ,  625 , and  615  in  FIG.  6   ) that may provide communication between two or more protocol layers. 
     The PHY  610  may transmit and receive physical layer signals  605  that may be received from or transmitted to one or more other communication devices. The physical layer signals  605  may comprise one or more physical channels, such as those discussed herein. The PHY  610  may further perform link adaptation or adaptive modulation and coding (AMC), power control, cell search (e.g., for initial synchronization and handover purposes), and other measurements used by higher layers, such as the RRC  655 . The PHY  610  may still further perform error detection on the transport channels, forward error correction (FEC) coding/decoding of the transport channels, modulation/demodulation of physical channels, interleaving, rate matching, mapping onto physical channels, and MIMO antenna processing. In embodiments, an instance of PHY  610  may process requests from and provide indications to an instance of MAC  620  via one or more PHY-SAP  615 . According to some embodiments, requests and indications communicated via PHY-SAP  615  may comprise one or more transport channels. 
     Instance(s) of MAC  620  may process requests from, and provide indications to, an instance of RLC  630  via one or more MAC-SAPs  625 . These requests and indications communicated via the MAC-SAP  625  may comprise one or more logical channels. The MAC  620  may perform mapping between the logical channels and transport channels, multiplexing of MAC SDUs from one or more logical channels onto TBs to be delivered to PHY  610  via the transport channels, de-multiplexing MAC SDUs to one or more logical channels from TBs delivered from the PHY  610  via transport channels, multiplexing MAC SDUs onto TBs, scheduling information reporting, error correction through HARQ, and logical channel prioritization. 
     Instance(s) of RLC  630  may process requests from and provide indications to an instance of PDCP  640  via one or more radio link control service access points (RLC-SAP)  635 . These requests and indications communicated via RLC-SAP  635  may comprise one or more RLC channels. The RLC  630  may operate in a plurality of modes of operation, including: Transparent Mode (TM), Unacknowledged Mode (UM), and Acknowledged Mode (AM). The RLC  630  may execute transfer of upper layer protocol data units (PDUs), error correction through automatic repeat request (ARQ) for AM data transfers, and concatenation, segmentation and reassembly of RLC SDUs for UM and AM data transfers. The RLC  630  may also execute re-segmentation of RLC data PDUs for AM data transfers, reorder RLC data PDUs for UM and AM data transfers, detect duplicate data for UM and AM data transfers, discard RLC SDUs for UM and AM data transfers, detect protocol errors for AM data transfers, and perform RLC re-establishment. 
     Instance(s) of PDCP  640  may process requests from and provide indications to instance(s) of RRC  655  and/or instance(s) of SDAP  647  via one or more packet data convergence protocol service access points (PDCP-SAP)  645 . These requests and indications communicated via PDCP-SAP  645  may comprise one or more radio bearers. The PDCP  640  may execute header compression and decompression of IP data, maintain PDCP Sequence Numbers (SNs), perform in-sequence delivery of upper layer PDUs at re-establishment of lower layers, eliminate duplicates of lower layer SDUs at re-establishment of lower layers for radio bearers mapped on RLC AM, cipher and decipher control plane data, perform integrity protection and integrity verification of control plane data, control timer-based discard of data, and perform security operations (e.g., ciphering, deciphering, integrity protection, integrity verification, etc.). 
     Instance(s) of SDAP  647  may process requests from and provide indications to one or more higher layer protocol entities via one or more SDAP-SAP  649 . These requests and indications communicated via SDAP-SAP  649  may comprise one or more QoS flows. The SDAP  647  may map QoS flows to DRBs, and vice versa, and may also mark QFIs in DL and UL packets. A single SDAP entity  647  may be configured for an individual PDU session. In the UL direction, the NG-RAN  310  may control the mapping of QoS Flows to DRB(s) in two different ways, reflective mapping or explicit mapping. For reflective mapping, the SDAP  647  of a UE  301  may monitor the QFIs of the DL packets for each DRB, and may apply the same mapping for packets flowing in the UL direction. For a DRB, the SDAP  647  of the UE  301  may map the UL packets belonging to the QoS flows(s) corresponding to the QoS flow ID(s) and PDU session observed in the DL packets for that DRB. To enable reflective mapping, the NG-RAN may mark DL packets over the Uu interface with a QoS flow ID. The explicit mapping may involve the RRC  655  configuring the SDAP  647  with an explicit QoS flow to DRB mapping rule, which may be stored and followed by the SDAP  647 . In embodiments, the SDAP  647  may only be used in NR implementations and may not be used in LTE implementations. 
     The RRC  655  may configure, via one or more management service access points (M-SAP), aspects of one or more protocol layers, which may include one or more instances of PHY  610 , MAC  620 , RLC  630 , PDCP  640  and SDAP  647 . In embodiments, an instance of RRC  655  may process requests from and provide indications to one or more NAS entities  657  via one or more RRC-SAPs  656 . The main services and functions of the RRC  655  may include broadcast of system information (e.g., included in MIBs or SIBs related to the NAS), broadcast of system information related to the access stratum (AS), paging, establishment, maintenance and release of an RRC connection between the UE  301  and RAN  310  (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), establishment, configuration, maintenance and release of point to point Radio Bearers, security functions including key management, inter-RAT mobility, and measurement configuration for UE measurement reporting. The MIBs and SIBs may comprise one or more IEs, which may each comprise individual data fields or data structures. 
     The NAS  657  may form the highest stratum of the control plane between the UE  301  and the AMF. The NAS  657  may support the mobility of the UEs  301  and the session management procedures to establish and maintain IP connectivity between the UE  301  and a P-GW in LTE systems. 
     According to various embodiments, one or more protocol entities of arrangement  600  may be implemented in UEs  301 , RAN nodes  311 , AMF in NR implementations or MME  421  in LTE implementations, UPF in NR implementations or S-GW  422  and P-GW  423  in LTE implementations, or the like to be used for control plane or user plane communications protocol stack between the aforementioned devices. In such embodiments, one or more protocol entities that may be implemented in one or more of UE  301 , gNB  311 , AMF, etc. may communicate with a respective peer protocol entity that may be implemented in or on another device using the services of respective lower layer protocol entities to perform such communication. In some embodiments, a gNB-CU of the gNB  311  may host the RRC  655 , SDAP  647 , and PDCP  640  of the gNB that controls the operation of one or more gNB-DUs, and the gNB-DUs of the gNB  311  may each host the RLC  630 , MAC  620 , and PHY  610  of the gNB  311 . 
     In a first example, a control plane protocol stack may comprise, in order from highest layer to lowest layer, NAS  657 , RRC  655 , PDCP  640 , RLC  630 , MAC  620 , and PHY  610 . In this example, upper layers  660  may be built on top of the NAS  657 , which includes an IP layer  661 , an SCTP  662 , and an application layer signaling protocol (AP)  663 . 
     In NR implementations, the AP  663  may be an NG application protocol layer (NGAP or NG-AP)  663  for the NG interface  313  defined between the NG-RAN node  311  and the AMF, or the AP  663  may be an Xn application protocol layer (XnAP or Xn-AP)  663  for the Xn interface  312  that is defined between two or more RAN nodes  311 . 
     The NG-AP  663  may support the functions of the NG interface  313  and may comprise Elementary Procedures (EPs). An NG-AP EP may be a unit of interaction between the NG-RAN node  311  and the AMF. The NG-AP  663  services may comprise two groups: UE-associated services (e.g., services related to a UE  301 ) and non-UE-associated services (e.g., services related to the whole NG interface instance between the NG-RAN node  311  and AMF). These services may include functions including, but not limited to: a paging function for the sending of paging requests to NG-RAN nodes  311  involved in a particular paging area; a UE context management function for allowing the AMF to establish, modify, and/or release a UE context in the AMF and the NG-RAN node  311 ; a mobility function for UEs  301  in ECM-CONNECTED mode for intra-system HOs to support mobility within NG-RAN and inter-system HOs to support mobility from/to EPS systems; a NAS Signaling Transport function for transporting or rerouting NAS messages between UE  301  and AMF; a NAS node selection function for determining an association between the AMF and the UE  301 ; NG interface management function(s) for setting up the NG interface and monitoring for errors over the NG interface; a warning message transmission function for providing means to transfer warning messages via NG interface or cancel ongoing broadcast of warning messages; a Configuration Transfer function for requesting and transferring of RAN configuration information (e.g., SON information, performance measurement (PM) data, etc.) between two RAN nodes  311  via CN  320 ; and/or other like functions. 
     The XnAP  663  may support the functions of the Xn interface  312  and may comprise XnAP basic mobility procedures and XnAP global procedures. The XnAP basic mobility procedures may comprise procedures used to handle UE mobility within the NG RAN  311  (or E-UTRAN  410 ), such as handover preparation and cancellation procedures, SN Status Transfer procedures, UE context retrieval and UE context release procedures, RAN paging procedures, dual connectivity related procedures, and the like. The XnAP global procedures may comprise procedures that are not related to a specific UE  301 , such as Xn interface setup and reset procedures, NG-RAN update procedures, cell activation procedures, and the like. 
     In LTE implementations, the AP  663  may be an S1 Application Protocol layer (S1-AP)  663  for the S1 interface  313  defined between an E-UTRAN node  311  and an MME, or the AP  663  may be an X2 application protocol layer (X2AP or X2-AP)  663  for the X2 interface  312  that is defined between two or more E-UTRAN nodes  311 . 
     The S1 Application Protocol layer (S1-AP)  663  may support the functions of the S1 interface, and similar to the NG-AP discussed previously, the S1-AP may comprise S1-AP EPs. An S1-AP EP may be a unit of interaction between the E-UTRAN node  311  and an MME  421  within an LTE CN  320 . The S1-AP  663  services may comprise two groups: UE-associated services and non UE-associated services. These services perform functions including, but not limited to: E-UTRAN Radio Access Bearer (E-RAB) management, UE capability indication, mobility, NAS signaling transport, RAN Information Management (RIM), and configuration transfer. 
     The X2AP  663  may support the functions of the X2 interface  312  and may comprise X2AP basic mobility procedures and X2AP global procedures. The X2AP basic mobility procedures may comprise procedures used to handle UE mobility within the E-UTRAN  320 , such as handover preparation and cancellation procedures, SN Status Transfer procedures, UE context retrieval and UE context release procedures, RAN paging procedures, dual connectivity related procedures, and the like. The X2AP global procedures may comprise procedures that are not related to a specific UE  301 , such as X2 interface setup and reset procedures, load indication procedures, error indication procedures, cell activation procedures, and the like. 
     The SCTP layer (alternatively referred to as the SCTP/IP layer)  662  may provide guaranteed delivery of application layer messages (e.g., NGAP or XnAP messages in NR implementations, or S1-AP or X2AP messages in LTE implementations). The SCTP  662  may ensure reliable delivery of signaling messages between the RAN node  311  and the AMF/MME  421  based, in part, on the IP protocol, supported by the IP  661 . The Internet Protocol layer (IP)  661  may be used to perform packet addressing and routing functionality. In some implementations the IP layer  661  may use point-to-point transmission to deliver and convey PDUs. In this regard, the RAN node  311  may comprise L2 and L1 layer communication links (e.g., wired or wireless) with the MME/AMF to exchange information. 
     In a second example, a user plane protocol stack may comprise, in order from highest layer to lowest layer, SDAP  647 , PDCP  640 , RLC  630 , MAC  620 , and PHY  610 . The user plane protocol stack may be used for communication between the UE  301 , the RAN node  311 , and UPF in NR implementations or an S-GW  422  and P-GW  423  in LTE implementations. In this example, upper layers  651  may be built on top of the SDAP  647 , and may include a user datagram protocol (UDP) and IP security layer (UDP/IP)  652 , a General Packet Radio Service (GPRS) Tunneling Protocol for the user plane layer (GTP-U)  653 , and a User Plane PDU layer (UP PDU)  663 . 
     The transport network layer  654  (also referred to as a “transport layer”) may be built on IP transport, and the GTP-U  653  may be used on top of the UDP/IP layer  652  (comprising a UDP layer and IP layer) to carry user plane PDUs (UP-PDUs). The IP layer (also referred to as the “Internet layer”) may be used to perform packet addressing and routing functionality. The IP layer may assign IP addresses to user data packets in any of IPv4, IPv6, or PPP formats, for example. 
     The GTP-U  653  may be used for carrying user data within the GPRS core network and between the radio access network and the core network. The user data transported can be packets in any of IPv4, IPv6, or PPP formats, for example. The UDP/IP  652  may provide checksums for data integrity, port numbers for addressing different functions at the source and destination, and encryption and authentication on the selected data flows. The RAN node  311  and the S-GW  422  may utilize an S1-U interface to exchange user plane data via a protocol stack comprising an L1 layer (e.g., PHY  610 ), an L2 layer (e.g., MAC  620 , RLC  630 , PDCP  640 , and/or SDAP  647 ), the UDP/IP layer  652 , and the GTP-U  653 . The S-GW  422  and the P-GW  423  may utilize an S5/S8a interface to exchange user plane data via a protocol stack comprising an L1 layer, an L2 layer, the UDP/IP layer  652 , and the GTP-U  653 . As discussed previously, NAS protocols may support the mobility of the UE  301  and the session management procedures to establish and maintain IP connectivity between the UE  301  and the P-GW  423 . 
     Moreover, although not shown by  FIG.  6   , an application layer may be present above the AP  663  and/or the transport network layer  654 . The application layer may be a layer in which a user of the UE  301 , RAN node  311 , or other network element interacts with software applications being executed, for example, by application circuitry  505 . The application layer may also provide one or more interfaces for software applications to interact with communications systems of the UE  301  or RAN node  311 . In some implementations the IP layer and/or the application layer may provide the same or similar functionality as layers 5-7, or portions thereof, of the Open Systems Interconnection (OSI) model (e.g., OSI Layer 7—the application layer, OSI Layer 6—the presentation layer, and OSI Layer 5—the session layer). 
       FIG.  7    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.  7    shows a diagrammatic representation of hardware resources  700  including one or more processors (or processor cores)  710 , one or more memory/storage devices  720 , and one or more communication resources  730 , each of which may be communicatively coupled via a bus  740 . For embodiments where node virtualization (e.g., NFV) is utilized, a hypervisor  702  may be executed to provide an execution environment for one or more network slices/sub-slices to utilize the hardware resources  700 . 
     The processors  710  may include, for example, a processor  712  and a processor  714 . The processor(s)  710  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  720  may include main memory, disk storage, or any suitable combination thereof. The memory/storage devices  720  may include, but are not limited to, any type of volatile or nonvolatile 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  730  may include interconnection or network interface components or other suitable devices to communicate with one or more peripheral devices  704  or one or more databases  706  via a network  708 . For example, the communication resources  730  may include wired communication components (e.g., for coupling via USB), cellular communication components, NFC components, Bluetooth® (or Bluetooth® Low Energy) components, Wi-Fi® components, and other communication components. 
     Instructions  750  may comprise software, a program, an application, an applet, an app, or other executable code for causing at least any of the processors  710  to perform any one or more of the methodologies discussed herein. The instructions  750  may reside, completely or partially, within at least one of the processors  710  (e.g., within the processor&#39;s cache memory), the memory/storage devices  720 , or any suitable combination thereof. Furthermore, any portion of the instructions  750  may be transferred to the hardware resources  700  from any combination of the peripheral devices  704  or the databases  706 . Accordingly, the memory of processors  710 , the memory/storage devices  720 , the peripheral devices  704 , and the databases  706  are examples of computer-readable and machine-readable media.

Metadata:
Filing Date: 20200515
Publication Date: 20230704
Grant Date: 20230704
Priority Date: 20190517
Inventors: MIAO, HONGLEI
Assignee: APPLE INC
CPC Classifications: [{"code": "H04B7/15542", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W88/085", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W28/26", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W28/16", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W28/26", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W88/085", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W92/20", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W28/26", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B7/15542", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B7/15542", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W88/085", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 71094807