Apparatus for updating contention window size and method thereof

Abstract

Apparatuses, methods, and systems are disclosed for adjusting contention window size. An apparatus (500, 600) includes a processor (505, 605) and a transceiver (525, 625) including a plurality of transmit panels. The transceiver (525, 625) initiates (705) a first channel occupancy ("CO") using at least one transmit panel in response to a successful listen-before-talk procedure and transmits (710) a directional transmission using a first transmit panel selected from the plurality of transmit panels. The processor (505, 605) determines (715) whether the directional transmission is successfully received by a recipient and updates (720) a first contention window size specific to the first transmit panel. The processor (505, 605) performs (725) a subsequent listen-before-talk procedure using the updated first contention window size prior to a subsequent directional transmission using the first transmit panel.

Description

[0001] Cross Reference to Related Applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 014,029, filed April 20, 2020, entitled “CONTENTION WINDOW SIZE ADJUSTMENT PROCEDURE,” by Karthikeyan Ganesan, Alexander Johann Maria Golitschek Edler von Elbwart, Ankit Bhamri, Ali Ramadan Ali, Vijay Nangia, and Ravi Kuchibhotla, which is incorporated by reference herein. TECHNICAL FIELD

[0003] The subject matter disclosed herein relates generally to wireless communications, and more particularly to adjusting a size of a contention window. BACKGROUND

[0004] In certain wireless communication systems, service is supplemented by operation on unlicensed spectrum. However, operation on unlicensed spectrum requires a clear channel assessment (“CCA”), such as involving a listen-before-talk (“LBT”) procedure, prior to transmission.

[0005] In Third Generation Partnership Project (“3GPP”) New Radio in unlicensed spectrum (“NR-U”), channel access for both downlink (“DL”) and uplink (“UL”) depends on CCA, such as an LBT procedure, to gain channel access. Before any transmission, a gNB (i.e., a Fifth Generation (“5G”) base station) and / or a user equipment (“UE”) must first sense the channel to find out if there is ongoing communication on the channel. LBT for Rel-16 NR-U does not consider beamforming and only assumes omni-directional LBT. SUMMARY

[0006] A procedure for adjusting a contention window size is disclosed. The procedure can be implemented by an apparatus, a system, a method, or a computer program product.

[0007] One method of a user equipment device ("UE") includes performing a listen- before-talk ("LBT") procedure for a set of transmit beams. The method includes performing a physical uplink control channel ("PUCCH") transmission on at least one beam of the set of transmit beams in response to a successful LBT of the transmit beam, and determining, at the UE, whether the PUCCH transmission was successfully received by a radio access network ("RAN") node. A second method includes updating a contention window size ("CWS") corresponding to each beam used in the PUCCH transmission, where a separate CWS is maintained for each transmission beam. In one embodiment, each CWS is adjusted to a next allowed value in response to determining that the PUCCH transmission was not successfully received by the RAN node. In another embodiment, each CWS is set to a minimum value in response to determining that the PUCCH transmission was successfully received by the RAN node.

[0008] One method of a communication device (e.g., a UE or gNB) includes initiating a first channel occupancy using at least one transmit beam in response to a successful LBT procedure and transmitting a directional transmission using a first transmit beam selected from a plurality of transmit beams. The first method includes determining, at the communication device, whether the directional transmission was successfully received by a recipient and updating a first CWS specific to the first transmit beam, where a separate CWS is maintained for each transmit beam that initiated the first channel occupancy. In one embodiment, updating the first CWS includes adjusting the first CWS to a next allowed value in response to determining that the directional transmission was not successfully received by the recipient. In another embodiment, updating the first CWS includes setting the first CWS to a minimum value in response to determining that the directional transmission was successfully received by the recipient. The first method includes performing a subsequent LBT procedure using the updated first CWS prior to a subsequent directional transmission using the first transmit beam. BRIEF DESCRIPTION OF DRAWINGS

[0009] A more particular description of the embodiments briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings. Understanding that these drawings depict only some embodiments and are not to be considered limitations of the scope of the disclosure, the embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

[0010] Figure 1 is a schematic block diagram illustrating one embodiment of a wireless communication system for irregular subcarrier spacing;

[0011] Figure 2 is a block diagram illustrating one embodiment of a Fifth Generation ("5G") New Radio ("NR") protocol stack;

[0012] Figure 3FIG. 1 is a diagram illustrating one embodiment of determining a reception status of a physical uplink control channel (“PUCCH”);

[0013] Figure 4 FIG. 2 is a diagram illustrating one embodiment of a radio frame during which an LBT procedure is performed;

[0014] Figure 5 FIG. 3 is a diagram illustrating one embodiment of a user equipment device that can be used to adjust contention window size;

[0015] Figure 6 FIG. 4 is a diagram illustrating one embodiment of a network device that can be used to adjust contention window size;

[0016] Figure 7 FIG. 5 is a flow diagram illustrating one embodiment of a method for adjusting contention window size; and

[0017] Figure 8 FIG. 5 is a flow diagram illustrating one embodiment of a method for adjusting contention window size. DETAILED DESCRIPTION

[0018] As those skilled in the art will appreciate, the various aspects of the embodiments can be embodied as a system, device, method or program product. Accordingly, the embodiments can take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects that can all generally be referred to herein as a “circuit,” “module” or “system.” Furthermore, the embodiments can take the form of a program product embodied in one or more computer readable storage medium(s) having computer readable program code embodied thereon.

[0019] For example, the disclosed embodiments can be implemented as a hardware circuit comprising custom very large scale integration (“VLSI”) circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. The disclosed embodiments can also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like. As another example, the disclosed embodiments can include one or more physical or logical blocks of executable code, which may, for example, be organized as an object, procedure, or function.

[0020] Furthermore, embodiments can take the form of a program product embodied in one or more computer readable storage devices storing machine-readable code, computer-readable code, and / or program code, hereinafter also referred to as code. The storage devices can be tangible, non-transitory, and / or non-transmission. The storage devices can not embody signals. In a certain embodiment, the storage devices only employ signals for accessing the code.

[0021] Any combination of one or more computer-readable media can be utilized. The computer-readable media can be a computer-readable storage medium. The computer-readable storage medium can be a storage device storing the code. The storage device can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing.

[0022] More specific examples (a non-exhaustive list) of the storage device would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory ("RAM"), a read-only memory ("ROM"), an erasable programmable read-only memory ("EPROM" or Flash memory), a portable compact disc read-only memory ("CD-ROM"), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer-readable storage medium can be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

[0023] Code for carrying out operations for embodiments can be any number of lines and can be written in any combination of one or more programming languages including an object- oriented programming language such as Python, Ruby, Java, Smalltalk, C++, or the like, and conventional procedural programming languages, such as the "C" programming language, or machine languages such as assembly languages. The code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network ("LAN"), wireless LAN ("WLAN"), or a wide area network ("WAN"), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider ("ISP")). The

[0024] Furthermore, the described features, structures, or characteristics of the embodiments can be combined in any suitable manner. In the following description, numerous specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., in order to provide a thorough understanding of the embodiments. One skilled in the relevant art will recognize, however, that the embodiments can be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail in order to avoid obscuring aspects of the embodiments.

[0025] References throughout this specification to “one embodiment,” “an embodiment,” or similar language do not necessarily refer to the same embodiment, but can comprise the same or similar characteristics, but are not necessarily coextensive. References to “an embodiment,” or similar languages, throughout this specification, mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but not always, all refer to the same embodiment, while the phrases “in one embodiment” and “in an embodiment” and similar language, mean that a particular feature, structure, or characteristic described in connection with one or more embodiments is included in at least one embodiment. The appearances of the phrases “in one embodiment” and “in an embodiment” in the specification are not necessarily all referring to the same embodiment, however, unless explicitly indicated otherwise. The terms “including,” “comprising,” “having” and variations thereof herein are meant to be broad and encompass the terms “consisting of” and “consisting essentially of.” Unless otherwise noted, the list of items does not imply that any or all of the items are mutually exclusive. Unless otherwise noted, the terms “a,” “an” and “the” refer to “one or more.”

[0026] As used herein, a list with “and / or” conjunction includes any single item in the list or a combination of items in the list. For example, a list of A, B and / or C includes only A, only B, only C, a combination of A and B, a combination of B and C, a combination of A and C, or a combination of A, B, and C. As used herein, a list using the term “one or more of’ includes any single item in the list or a combination of items in the list. For example, one or more of A, B and C includes only A, only B, only C, a combination of A and B, a combination of B and C, a combination of A and C, or a combination of A, B, and C. As used herein, a list using the term “one of’ includes one and only one of the items in the list. For example, “one of A, B, and C” includes only A, only B, or only C and not a combination of A, B, and C. As used herein, “a member selected from the group consisting of A, B, and C” includes one and only one of A, B, or C, and not a combination of A, B, and C. As used herein, “a member selected from the group consisting of A, B, and C, and combinations thereof’ includes only A, only B, only C, a combination of A and B, a combination of B and C, a combination of A and C, or a combination of A, B, and C.

[0027] Various aspects of embodiments are described in further detail below with reference to schematic flowcharts and / or schematic block diagrams of methods, apparatuses, systems, and program products according to embodiments. It will be understood that each block of the schematic flowchart and / or schematic block diagrams, and combinations of blocks in the schematic flowchart and / or schematic block diagrams, can be implemented by code. The code can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the code, which executes via the processor of the computer or other programmable data processing apparatus, creates means for implementing the functions / acts specified in the flowchart and / or schematic block diagram.

[0028] The code can also be stored in a storage device that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the storage device produce an article of manufacture including instructions which implement the

[0029] The code can also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the code which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flowchart and / or block diagram.

[0030] The flowchart and / or block diagrams in the drawings illustrate the architecture, functionality, and operation of possible implementations of apparatuses, systems, methods and computer program products according to various embodiments. In this regard, each block in the flowchart and / or block diagrams can represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical functions.

[0031] It should also be noted that in some alternative implementations, the functions noted in the blocks can occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently or the blocks can sometimes be executed in the reverse order, depending upon the functionality involved. Such variation, function, logic or

[0032] Although various arrow types and line types can be employed in the flowchart and / or block diagrams, they are understood not to limit the scope of the corresponding embodiments. Indeed, some arrows or other connectors can be used to indicate only the logical flow of the depicted embodiment. For instance, an arrow can indicate a waiting or monitoring period of unspecified duration between enumerated steps of the depicted embodiment. It will also be noted that each block of the block diagrams and / or flowchart illustrations, and combinations of blocks in the block diagrams and / or flowchart illustrations, can be implemented by special-purpose hardware-based systems that perform the specified functions or acts, or combinations of special-purpose hardware and code.

[0033] The description of elements in each figure can refer to elements in previous figures. Like numbers refer to like elements in all figures, including alternative embodiments of like elements.

[0034] In general, the present disclosure describes systems, methods, and apparatuses for adjusting contention window size. The present disclosure addresses channel access mechanisms for high frequency ranges, i.e., frequency range 2 (“FR2,” including frequency bands from 24.25 GHz to 52.6 GHz) and beyond unlicensed bands. More specifically, since beam-based operation is assumed for unlicensed spectrum for operating frequencies of FR2 and above 52.6 GHz, it is critical to perform LBT in a specific beam direction(s) instead of omni-directional LBT.

[0035] In NR-U, channel access in both downlink and uplink relies on LBT; however, LBT in Rel-16 NR-U does not consider beamforming and assumes only omni-directional LBT. The MAC layer entity of a UE relies on receiving an UL LBT failure notification from the physical layer to detect a consistent UL LBT failure. The NR-U LBT procedure for channel access can be summarized as follows:

[0036] A) Both gNB-initiated channel occupancy time (“COT”) and UE-initiated COT use Category 4 (“Cat-4”) LBT, where the start of a new transmission burst always performs LBT with exponential backoff. There is an exception only when the duration of DRS must be at most one ms and not multiplexed with unicast PDSCH. As used herein, a Cat-4 LBT procedure refers to an LBT with random backoff and with a variable size contention window.

[0037] B) UL transmissions within a gNB-initiated channel occupancy time (“COT”) or subsequent DL transmissions within a UE- or gNB-initiated COT can be transmitted immediately without sensing only when the gap from the end of the previous transmission is not greater than 16 μβ, otherwise Category 2 (“Cat-2”) LBT must be used and the gap cannot exceed 25 μβ. As used herein, a Cat-2 LBT procedure refers to an LBT without random backoff.

[0038] In various embodiments, PUCCH reception status can be determined in one of the following ways. A) based on comparison of the toggled / non-toggled NDI from the subsequent DCI to the corresponding transmitted HARQ feedback report; B) based on comparison of the DAI value in the subsequent DCI to the corresponding transmitted HARQ feedback report; or C) an explicit indication in the DCI informs the CWS adjustment for PUCCH.

[0039] For CW adjustment for transmissions including PDSCH and PUSCH: If new HARQ feedback is available relative to the prior CW update, the feedback for the latest COT in which the new feedback is received should be used: If the HARQ feedback is ACK, the CW will be set to CWmin. If the HARQ feedback is NACK (or if the gNB or UE retransmit the TB without feedback within a window as defined below), the CW will be set to min(CW x 2 + 1, CWmax).

[0040] The contention window starts at the end of the reference duration and has a duration of max(X ms, duration of the transmission burst from the start of the reference duration + 1 ms). If the absence of other techniques cannot be guaranteed (for other case conditions same as in existing specifications), X = 5. Otherwise, X = 10. Otherwise (if new HARQ feedback is not available), the CW will remain unchanged. Note that HARQ feedback includes any implicit methods of HARQ feedback determination.

[0041] Regarding HARQ feedback, according to a first option, one PUCCH can carry HARQ-ACK feedback for one or multiple PDSCH groups. DCI can request HARQ-ACK feedback for one or multiple PDSCH groups. In one embodiment, C-DAI / T-DAI can accumulate across multiple PDSCH groups requesting feedback in the same PUCCH. In another embodiment, C-DAI / T-DAI accumulates only within one PDSCH group. In certain embodiments, there is a new ACK feedback group indicator for each PDSCH group. The number of HARQ-ACK bits for one PDSCH group is constant between the first HARQ-ACK feedback transmission and the HARQ-ACK feedback retransmission, i.e., the PDSCH group cannot be enlarged after the first feedback transmission.

[0042] However, according to a second option, one PUCCH can carry HARQ-ACK feedback for a single PDSCH group. DCI can request HARQ-ACK feedback for a single PDSCH group. C-DAI / T-DAI accumulates within one PDSCH group. A reset indicator signals new HARQ-ACK feedback for a PDSCH group. The number of HARQ-ACK bits for one PDSCH group can not be constant between the first HARQ-ACK feedback transmission and the HARQ-ACK feedback retransmission.

[0043] If a request / trigger for single-shot group HARQ ACK feedback is introduced for all configured HARQ processes (at least for non-CBG HARQ), one or more of the following candidate solutions is selected: A) The request is carried in UE-specific DCI carrying PUSCH grant; B) The request is carried in UE-specific DCI carrying PDSCH assignment; C) The request is carried in UE-specific DCI that neither schedules PDSCH nor schedules PUSCH; D) The request is carried in UE-common DCI; E) The request can be used for UEs configured with dynamic or semi-static HARQ codebook. Thus, the network can support requesting feedback of HARQ-ACK codebook containing all DL HARQ processes (single-shot feedback) in PUCCH group for all CCs configured for a UE. Single-shot feedback will be configured separately from the configuration of semi-static (including any potential enhancements) / non-enhanced dynamic HARQ codebook.

[0044] In some embodiments, if a UE is configured to monitor feedback request of HARQ-ACK codebook containing all DL HARQ processes (single-shot feedback). In certain embodiments, the feedback can only be requested in UE-specific DCI. In certain embodiments, the feedback can be requested for reporting in PUCCH. Note that HARQ feedback can be piggybacked on PUSCH.

[0045] To incorporate LBT into the channel access mechanism for both data and control channels, the contention window size (“CWS”) adjustment update procedure for PUCCH and PUSCH and PDSCH takes into account directional LBT. In various embodiments, the channel access mechanism is omnidirectional in the Cat 4 LBT case.

[0046] In some embodiments, CWS adjustment is performed independently per Tx beam / panel (or Tx spatial filter, Tx spatial setting, Tx spatial relation, and / or TCI state) for data channels. Here, the contention window size for a data channel (e.g., PUSCH / PDSCH / PSSCH) is determined for a subsequent LBT / CCA procedure taking into account the Tx spatial setting of the data channel for which a HARQ-ACK feedback report is generated, and not dependent on the spatial setting of the control channel from which the HARQ-ACK / NACK feedback report is transmitted.

[0047] In some embodiments, when the UE has an ongoing UL transmission in a first beam / panel / space filter, the UE can initiate a second LBT on a set of Tx panels / beams / space filters (indicated by gNB) using a second Tx beam / panel / space filter in a time-domain manner or concurrently (parallel LBT). In certain embodiments, the CWS adjustment procedure for each of the multiple Tx beams / panels / space filters is done according to the highest priority CAPC currently used for LBT. Here, the generated TB can be transmitted in any of the Tx beams / panels / space filters, whichever has the minimum CWS for transmission from the time the TB is generated.

[0048] In certain embodiments, the CWS adjustment procedure for multiple Tx beams / panels / space filters is done independently for each Tx beam / panel / space filter according to the CAPC value used when performing LBT. If the UE uses the same TX beam / panel / space filter to transmit data belonging to the first LBT and the second LBT, the CWS adjustment procedure for that Tx beam / panel / space filter is done according to the highest priority CAPC.

[0049] The contention window size adjustment of the beam / panel / space filter used for PUCCH transmission can be based on the PUCCH reception status at the gNB. When PUCCH decoding fails or is DTX at the gNB, the CWS of the corresponding beam / panel / space filter that transmitted the PUCCH is increased to the next value or doubled.

[0050] Figure 1 A wireless communication system 100 for adjusting contention window size according to embodiments of the present disclosure is depicted. In one embodiment, the wireless communication system 100 includes at least one remote unit 105, a radio access network (“RAN”) 120, and a mobile core network 130. The RAN 120 and the mobile core network 130 form a mobile communication network. The RAN 120 can be composed of a base unit 121 with which the remote unit 105 communicates using a wireless communication link 123. Although a certain number of remote units 105, base units 121, wireless communication links 123, a RAN 120, and a mobile core network 130 are depicted in Figure 1 A certain number of remote units 105, base units 121, wireless communication links 123, a RAN 120, and a mobile core network 130 are depicted in FIG. 1 to approximate the complexity of a wireless communication system 100. One of skill in the art will recognize that any number of remote units 105, base units 121, wireless communication links 123, RANs 120, and mobile core networks 130 can be included in a wireless communication system 100.

[0051] In one implementation, the RAN 120 is compliant with the 5G system specified in the Third Generation Partnership Project (“3GPP”) specifications. For example, the RAN 120 can be an NG-RAN that implements NR RAT and / or LTE RAT. In another example, the RAN 120 can include non-3GPP RAT (e.g., Wi-Fi®) access networks. In another implementation, the RAN 120 is compliant with the LTE system specified in the 3GPP specifications. More generally, however, the wireless communication system 100 can implement some other open or proprietary communication network standards, for example, Worldwide Interoperability for Microwave Access (“WiMAX”) or IEEE 802.16 standards, among other networks. The present disclosure is not intended to be limited to the implementation of any particular wireless communication system architecture or protocol.

[0052] In one embodiment, the remote units 105 can include computing devices, such as desktop, laptop, personal digital assistant (“PDA”), tablet computer, smart phone, smart television (e.g., television connected to the Internet), smart appliance (e.g., appliance connected to the Internet), set-top box, game console, security system (including security camera), vehicle

[0053] ​The remote units 105 can directly communicate with one or more base units 121 of the RAN 120 via uplink (“UL”) and downlink (“DL”) communication signals. The UL and DL communication signals can be carried over the wireless communication links 123. Here, the RAN 120 is an intermediate network that provides the remote units 105 with access to a mobile core network 130. As described in more detail below, the RAN 120 can transmit measurement and reporting configuration 111 to the remote units 105, where the remote units 105 transmit measurement reports 113 to the RAN 120.

[0054] In some embodiments, the remote units 105 communicate with the application server 141 via a network connection with the mobile core network 130. For example, an application 107 (e.g., a web browser, a media client, a telephone, and / or a Voice-over-Internet Protocol (“VoIP”) application) in a remote unit 105 can trigger the remote unit 105 to establish a protocol data unit (“PDU”) session (or other data connection) with the mobile core network 130 via the RAN 120. The mobile core network 130 then relays traffic between the remote unit 105 and the application server 141 in the packet data network 140 using the PDU session. The PDU session represents a logical connection between the remote unit 105 and a user plane function (“UPF”) 131.

[0055] To establish a PDU session (or PDN connection), the remote unit 105 must register with the mobile core network 130 (also referred to as “attaching to the mobile core network” in the context of fourth generation (“4G”) systems). Note that a remote unit 105 can establish one or more PDU sessions (or other data connections) with the mobile core network 130. Thus, a remote unit 105 can have at least one PDU session for communicating with the packet data network 140. The remote unit 105 can establish additional PDU sessions for communicating with other data networks and / or other communication peers.

[0056] In the context of a 5G system (“5GS”), the term “PDU session” refers to a data connection that provides end-to-end (“E2E”) user plane (“UP”) connectivity between a remote unit 105 and a specific data network (“DN”) through a UPF 131. A PDU session supports one or more quality of service (“QoS”) flows. In certain embodiments, there can be a one-to-one mapping between a QoS flow and a QoS profile, such that all packets belonging to a particular QoS flow have the same 5G QoS identifier (“5QI”).

[0057] In the context of a 4G / LTE system, such as an Evolved Packet System (“EPS”), a Packet Data Network (“PDN”) connection (also referred to as an EPS session) provides E2E UP connectivity between a remote unit and a PDN. A PDN connectivity procedure establishes an EPS bearer, i.e., a tunnel between the remote unit 105 and a Packet Gateway (“PGW”, not shown) in the mobile core network 130. In certain embodiments, there is a one-to-one mapping between an EPS bearer and a QoS profile, such that all packets belonging to a particular EPS bearer have the same QoS class identifier (“QCI”).

[0058] The base units 121 can be distributed over a geographic region. In certain embodiments, the base units 121 can also be referred to as access terminals, access points, bases, base stations, Node Bs (“NBs”), Evolved Node Bs (abbreviated as eNodeBs or “eNBs,” also referred to as Evolved Universal Terrestrial Access Network (“E-UTRAN”) Node Bs), 5G / NR Node Bs (“gNBs”), Home NodeBs, relay nodes, RAN nodes, or by any other terminology used in the art. The base units 121 are generally part of a RAN, such as the RAN 120, which can include one or more controllers that can be communicably coupled to one or more corresponding base units 121. These and other elements of radio access networks are not illustrated but are well known in the art. The base units 121 connect to the mobile core network 130 via the RAN 120.

[0059] The base units 121 can serve various geographic areas that are collectively referred to as a cell, a cell sector, or similar terms known in the art. The base units 121 can communicate with one or more of the remote units 105 via a wireless communication link 123. Generally, the base units 121 transmit DL communication signals to serve the remote unit 105 in the time, frequency, and / or spatial domain. Additionally, the DL communication signals can be carried on the wireless communication link 123. The wireless communication link 123 can be any suitable carrier in a licensed or unlicensed radio frequency spectrum band. The wireless communication link 123 facilitates communication between one or more of the remote units 105 and / or one or more of the base units 121. Note that during NR-U operation, the base units 121 and the remote units 105 communicate over unlicensed radio frequency spectrum.

[0060] In one embodiment, the mobile core network 130 is a 5GC or an Evolved Packet Core (“EPC”), which can be coupled to packet data networks 140, like the Internet and private data networks, as well as other data networks. The remote units 105 can have a subscription or other account with the mobile core network 130. Each mobile core network 130 belongs to a single PLMN. The present disclosure is not intended to be limited to the implementation of any particular wireless communication system architecture or protocol.

[0061] The mobile core network 130 includes a number of network functions (“NFs”). As depicted, the mobile core network 130 includes at least one UPF 131. The mobile core network 130 also includes a number of control plane functions (“CPs”), including but not limited to an Access and Mobility Management Function (“AMF”) 133, a Session Management Function (“SMF”) 135, a Policy Control Function (“PCF”) 137, and a Unified Data Management function (“UDM”). In some embodiments, the UDM is quasi co-located with a user data repository (“UDR”), which is depicted as the combined entity “UDM / UDR” 139. In various embodiments, the mobile core network 130 can also include an Authentication Server Function (“AUSF”), a Network Repository Function (“NRF”) (used by the various NFs to discover and communicate with each other over application programming interfaces (“APIs”)), or other NFs defined for the 5GC. In certain embodiments, the mobile core network 130 can include an authentication, authorization, and accounting (“AAA”) server.

[0062] In various embodiments, the mobile core network 130 supports different types of mobile data connections and different types of network slices, where each mobile data connection utilizes a particular network slice. Here, a “network slice” refers to a part of the mobile core network 130 that is optimized for a certain traffic type or communication service. A network instance can be identified by a single-network slice selection assistance information (“S-NSSAI”), while a set of network slices for which a remote unit 105 is authorized to use is identified by network slice selection assistance information (“NSSAI”). Here, “NSSAI” refers to a vector value that includes one or more S-NSSAI values. In certain embodiments, the various network slices can include separate instances of network functions, such as the SMF 135 and UPF 131. In some embodiments, different network slices can share some common network functions, such as the AMF 133. For ease of illustration, different network slices are not shown in Figure 1 but their support is assumed.

[0063] Although in Figure 1The depicted network functions are specific in number and type, but one of skill in the art will recognize that any number and type of network functions can be included in the mobile core network 130. Moreover, in a LTE variant in which the mobile core network 130 is an EPC, the depicted network functions can be replaced with appropriate EPC entities, such as a mobility management entity (“MME”), a serving gateway (“SGW”), a PGW, a home subscriber server (“HSS”), etc. For example, the AMF 133 can be mapped to a MME, the SMF 135 can be mapped to a control plane portion of a PGW and / or to a MME, the UPF 131 can be mapped to a SGW and a user plane portion of a PGW, the UDM / UDR 139 can be mapped to a HSS, etc.

[0064] While Figure 1 Components of a 5G RAN and a 5G core network are depicted, the described embodiments for adjusting contention window size apply to other types of communication networks and RATs, including IEEE 802.11 variants, Global System for Mobile Communications (“GSM”, i.e., a 2G digital cellular network), General Packet Radio Service (“GPRS”), Universal Mobile

[0065] In the following description, the term “gNB” is used for the base station, but it can be replaced with any other RAN node, e.g., eNB, base station (“BS”), access point (“AP”), etc. Moreover, the operations are described mainly in the context of 5G NR. However, the proposed solutions / methods are equally applicable to other mobile communication systems as well.

[0066] Figure 2 A NR protocol stack 200 is depicted in accordance with embodiments of the disclosure. While Figure 2The diagram shows UE 205, gNB 210, and AMF 215 in the 5G core network (“5GC”), but these represent a collection of remote units 105 that interact with base station unit 121 and NF in mobile core network 140. As depicted, protocol stack 200 includes user plane protocol stack 220 and control plane protocol stack 225. User plane protocol stack 220 includes physical (“PHY”) layer 230, media access control (“MAC”) sublayer 235, radio link control (“RLC”) sublayer 240, packet data convergence protocol (“PDCP”) sublayer 245, and service data adaptation protocol (“SDAP”) layer 250. Control plane protocol stack 225 includes physical layer 230, MAC sublayer 235, RLC sublayer 240, and PDCP sublayer 245. Control plane protocol stack 225 also includes radio resource control (“RRC”) layer 255 and non-access stratum (“NAS”) layer 260.

[0067] The AS layer (also referred to as the "AS protocol stack") for the user plane protocol stack 220 consists of at least SDAP, PDCP, RLC, and MAC sublayers, as well as a physical layer. The AS layer for the control plane protocol stack 225 consists of at least RRC, PDCP, RLC, and MAC sublayers, as well as a physical layer. Layer 2 ("L2") is divided into SDAP, PDCP, RLC, and MAC sublayers. Layer 3 ("L3") includes the RRC sublayer 255 and NAS layer 260 for the control plane and includes, for example, an Internet Protocol ("IP") layer or a PDU layer (not depicted) for the user plane. L1 and L2 are referred to as "lower layers," while L3 and higher layers (e.g., transport layer, application layer) are referred to as "higher layers" or "upper layers."

[0068] Physical layer 230 provides a transport channel to MAC sublayer 235. As described herein, physical layer 230 can perform CCA / LBT procedures. In some embodiments, physical layer 230 can send a notification of UL LBT failure to the MAC entity at MAC sublayer 235. MAC sublayer 235 provides a logical channel to RLC sublayer 240. RLC sublayer 240 provides an RLC channel to PDCP sublayer 245. PDCP sublayer 245 provides radio bearers to SDAP sublayer 250 and / or RRC layer 255. SDAP sublayer 250 provides QoS flows to the core network (e.g., 5GC). RRC layer 255 provides the addition, modification, and release of carrier aggregation and / or dual connectivity. RRC layer 255 also manages the establishment, configuration, maintenance, and release of signaling radio bearers (“SRBs”) and data radio bearers (“DRBs”).

[0069] NAS layer 260 is located between UE 205 and 5GC 215. NAS messages are transparently transmitted through the RAN. NAS layer 260 is used to manage the establishment of communication sessions and to maintain continuous communication with UE 205 when UE 205 moves between different cells in the RAN. In contrast, AS layer is located between UE 205 and the RAN that carries information through the radio portion of the network.

[0070] Regarding the channel access procedure, several categories of LBTs are defined in NR-U. For category-1 (“Cat-1”), there is no LBT; for category-2 (“Cat-2”), there is an LBT without random backoff; for category-3 (“Cat-3”), there is an LBT with random backoff and a fixed contention window size (“CWS”); and for category-4 (“Cat-4”), there is an LBT with random backoff and a variable CWS.

[0071] The contention window increases exponentially with each collision and is reset to its minimum once a transmission is successful. Given the randomness of the backoff process, different devices will have different backoff intervals, thus improving channel adaptation. If a recent downlink transmission burst exhibits 80% or more decoding errors, as reported via HARQ feedback (NACK) from UE 205, the contention window (CW) doubles for the next LBT.

[0072] When performing a "Listen Before Talk" ("LBT"), the device backs off for a certain number of idle time slots. As discussed further below, if the channel remains idle for the delay duration (Td), it is considered idle. To reduce the likelihood of collisions, the device needs to back off for varying amounts of idle time slots. After a successful LBT, the device initiates a channel occupancy and is granted access to the channel for a specific duration called the Channel Occupancy Time ("COT").

[0073] UE 205 can access a channel on which one or more UL transmissions will be performed, based on either Type 1 or Type 2 channel access. In various embodiments, a prerequisite for channel access is that UE 205 receives UL permission to schedule time / frequency resources, i.e., a set of one or more resource blocks. Resources in the time domain can be referred to as symbols, time slots, time slots, subframes, frames, etc. Resources in the frequency domain can be referred to as subcarriers. A grouping of subcarriers over a time unit can be referred to as a resource block.

[0074] In one embodiment, the (dynamic) UL authorization for scheduling PUSCH transmissions can indicate a Type 1 channel access procedure. In another embodiment, the (dynamic) UL authorization for scheduling PUSCH transmissions can indicate a Type 2 channel access procedure. UE 205 can use the Type 1 channel access procedure to transmit autonomous or configured authorized PUSCH transmissions using configured UL resources. UE 205 can also use the Type 1 channel access procedure to transmit PUCCH and / or for SRS transmissions that do not include PUSCH (i.e., data) transmissions.

[0075] UE 205 can first sense the channel during the delay duration T d After the time slot duration is idle and after the counter N is zero in step 4, a type 1 channel access procedure is used to transmit the transmission. Here, it is assumed that the duration spanned by the sensing time slots sensed as idle before (one or more) UL transmissions is random. The counter N is adjusted by sensing the channel (one or more) of the additional time slot duration according to the steps described below.

[0076] 1) Set N = N init , where N init It is evenly distributed between 0 and CW. p A random number between the given values ​​is generated, and then proceed to step 4;

[0077] 2) If N>0 and UE 205 selects a decrementing counter, then set N=N-1;

[0078] 3) Sensing the channel during the additional time slot duration, and if the additional time slot duration is idle, proceed to step 4; otherwise, proceed to step 5;

[0079] 4) If N = 0, stop; otherwise, go to step 2.

[0080] 5) Sensing channel until the additional delay duration T d All time slots that were detected as busy or with an additional delay duration were detected as idle;

[0081] 6) If the channel is detected as having an additional delay duration T d If the time slot is idle during all its duration, proceed to step 4; otherwise, proceed to step 5.

[0082] If UE 205 has not yet transmitted a UL transmission on the channel performing one or more UL transmissions after step 4 of the above process, and if the channel is ready to transmit a transmission at least for the sensing time slot duration T... sl The channel is sensed to be idle, and if the channel is delayed for a duration T immediately preceding the transmission. dIf the channel has been sensed as idle for the entire duration of the time slot, then UE 205 may transmit on that channel. If UE 205 senses the channel first after it is ready to transmit, then the channel is idle for the entire duration of the sensing time slot T. sl The channel has not yet been sensed as idle, or if the channel is immediately followed by a delay duration T prior to the intended transmission. d If a channel has not been sensed as idle during any sensing time slot duration, then UE 205 will detect that the channel is idle during the delay duration T. d If the time slot duration is idle, proceed to step 1.

[0083] Delay duration T d Following immediately is m p The duration T of a consecutive time slot f =16us, where the duration of each time slot is T sl =9us, and T f Included in T f Initial idle time slot duration T sl .

[0084] CW min,p ≤CW p ≤CW max,p It is a competitive window. The CW is described below. p Adjustments. Note: CW min,p and CW max,p It was selected before step 1 of the above process. Also note that CW... min,p and CW max,p It is based on, for example, the channel access priority class that is sent to UE 205 by a signal.

[0085] If UE 205 transmits on a channel using a Type 1 channel access procedure associated with channel access priority class p, then UE 205 maintains the contention window value CW. p And adjust the CW for those transmissions before step 1 of the process described in Clause 4.2.1.1 using the following steps. p .

[0086] 1) For each priority class p∈{1,2,3,4}, set CW p =CW min,p ;

[0087] 2) If HARQ-ACK feedback is in CW p If the last update is available, proceed to step 3. Otherwise, if the UE 205 transmission following the procedure described in Clause 4.2.1.1 does not include retransmissions, or if the duration T from the end of the reference duration is...w If the signal is emitted within the specified time, proceed to step 5, where the reference duration is the same as the CW emitted after the process described in Clause 4.1.1. p The earliest UL transmission burst after the last update corresponds to the current one; otherwise, proceed to step 4.

[0088] 3) In the reference duration of the latest UL transmission burst available for HARQ-ACK feedback, the HARQ-ACK feedback corresponding to (one or more) PUSCHs is used as follows:

[0089] a. If at least one HARQ-ACK feedback is an 'ACK' for one or more PUSCHs with a transport block (TB) based transmission, or if at least 10% of the HARQ-ACK feedbacks are 'ACK' for one or more PUSCHs with a code block group (CBG) based transmission, then proceed to step 1; otherwise proceed to step 4.

[0090] 4) Apply CW to each priority class p∈{1,2,3,4} p Increase to the next higher allowed value;

[0091] 5) For each priority class p∈{1,2,3,4}, maintain CW as is. p Turning to step 2.

[0092] The above process includes HARQ-ACK feedback, reference duration, and duration T. w It is defined as follows.

[0093] • HARQ-ACK feedback for one or more PUSCH transmissions is expected to be provided explicitly or implicitly to one or more UEs 205, wherein implicit HARQ-ACK feedback for the purpose of contention window adjustment in this clause is determined based on the indication of a new transmission or retransmission in the DCI that schedules one or more PUSCHs:

[0094] If a new transmission is indicated, then 'ACK' is assumed for the transport block or code block group in the corresponding PUSCH(s) for TB-based transmissions and CBG-based transmissions, respectively.

[0095] ○ If a retransmission is indicated for a TB-based transmission, then 'NACK' is assumed for the transport block(s) in the corresponding PUSCH(s).

[0096] ○ If a retransmission is indicated for a CBG-based transmission, if the bit value in the Block Group Transmission Information (CBGTI) field is '0' or '1', then 'ACK' or 'NACK' is assumed for the corresponding CBG in (one or more) corresponding PUSCHs, respectively.

[0097] The reference duration corresponding to a channel occupancy initiated by UE 205 that includes one or more PUSCH transmissions is defined in this clause as the duration from the beginning of the channel occupancy until the end of the first time slot in which at least one unicast PUSCH is transmitted on all resources allocated for the PUSCH, or until the end of the first transmission burst by UE 205 that includes one or more unicast PUSCHs transmitted on all resources allocated for the PUSCH (whichever occurs earlier). If the channel occupancy includes a unicast PUSCH, but it does not include any unicast PUSCHs transmitted on all resources allocated for that PUSCH, then the duration of the first transmission burst by UE 205 within the channel occupancy that includes one or more PUSCHs is the reference duration for CWS adjustment.

[0098] ·T w =max(T) A ,T B +1ms), where T B T is the duration of the transmission burst, measured in milliseconds, starting from the reference duration, and is further defined if the absence of any other technique for sharing the channel on a long-term basis (e.g., by adjusting the level) cannot be guaranteed. A =5ms, otherwise T A =10ms.

[0099] If UE 205 transmits a transmission on a channel using a Type 1 channel access procedure associated with channel access priority class p, and the transmission is not associated with explicit or implicit HARQ-ACK feedback as described above in this clause, then UE 205 uses the latest CW for any UL transmissions using a Type 1 channel access procedure associated with channel access priority class p on the channel. p Adjust CW prior to step 1 in the process described in Clause 4.2.1.1. p If the corresponding channel access priority class p has not yet been used for any UL transmission on the channel, then CW is used. p =CW min,p .

[0100] As used herein, if a single value is configured for pucch-SpatialRelationInfoId for UE 205, the spatial settings for PUCCH transmission are provided by the Layer 1 (“L1”) parameter PUCCH-SpatialRelationInfo; otherwise, if multiple values ​​are provided for PUCCH-SpatialRelationInfo for UE 205, UE 205 determines the spatial settings for PUCCH transmission. An example mechanism for determining the spatial settings is described in 3GPP TS 38.321. UE 205 applies the corresponding settings to the spatial domain filter in the time slot. In the first time slot thereafter, PUCCH is transmitted, where k is the time slot in which UE 205 will transmit PUCCH with HARQ-ACK information corresponding to the ACK value of the PDCCH receiving the PDCCH with the provided information element (“IE”) PUCCH-SpatialRelationInfo, and μ is the SCS configuration for PUCCH.

[0101] If the PUCCH-SpatialRelationInfo provides the parameter ssb-Index, UE 205 transmits the PUCCH for the same serving cell using the same spatial domain filter used for receiving SS / PBCH blocks with the index provided by ssb-Index; or, if the servingCellId parameter is provided, it transmits the PUCCH for the serving cell indicated by the servingCellId. Otherwise, if the PUCCH-SpatialRelationInfo provides the parameter csi-RS-Index, UE 205 transmits the PUCCH for the same serving cell using the same spatial domain filter used for receiving CSI-RS blocks with the resource index provided by csi-RS-Index; or, if the servingCellId parameter is provided, it transmits the PUCCH for the serving cell indicated by the servingCellId. Otherwise, if the PUCCH-SpatialRelationInfo provides the parameter srs, the UE 205 transmits the PUCCH for the same serving cell and / or active UL BWP using the same spatial domain filter used for transmissions of probe reference signals (“SRS”) with resource indices provided by resources, or if one or more parameters servingCellId and / or uplinkBWP are provided, the PUCCH is transmitted for the serving cell indicated by servingCellId and / or for the UL bandwidth portion (“BWP”) indicated by uplinkBWP.

[0102] If UE 205(a) reports beamCorrespondenceWithoutUL-BeamSweeping, and(b) is not provided with the parameter pathlossReferenceRSs in IEPUCCH-PowerControl, and(c) is provided with enableDefaultBeamPlForPUCCH, and(d) is not provided with PUCCH-SpatialRelationInfo, then the spatial settings for PUCCH transmissions from UE 205 are the same as the spatial settings for PDCCH reception by UE 205 on the active DL BWP in the primary cell (“PCell”) in the CORESET with the lowest ID.

[0103] According to an embodiment of the first solution, the contention window size adjustment for the channel access priority class (“CAPC”) for the data channel and / or control channel depends on (i.e., based on) the Tx beam / panel for which the HARQ report was generated (or alternatively, depends on the Tx spatial filter, Tx spatial setting, Tx spatial relation, and / or TCI state). In one example, the CWS is maintained / adjusted for each TX beam / space (or alternatively, TX spatial filter / space setting / space relation / TCI state) associated with data / control channel transmissions that initiate channel occupancy using Cat 4 LBT. Hereinafter, it is assumed that CWS adjustment is performed independently on a per TX panel / beam / space filter / space setting / space relation / TCI state basis.

[0104] In the first solution, the CWS adjustment for determining the TX beam / panel (or alternatively, TX spatial filter) (or associated with the spatial setup, spatial relation, and / or TCI state for data channel transmission) for any subsequent LBT can be based on HARQ feedback (i.e., HARQ-ACK / NACK) for data channel reception. Note that the determination of the CWS adjustment depends on the TX spatial filter / spatial setup / spatial relation / TCI state of the corresponding data channel on which the HARQ-ACK report was generated. Importantly, the determination of the CWS adjustment does not depend on the RX beam / panel, Rx spatial filter, Rx spatial setup, Rx spatial relation, or TCI state of the control channel on which the HARQ-ACK / NACK feedback report was received. The data channel can be any of the Physical Downlink Shared Channel (“PDSCH”), Physical Uplink Shared Channel (“PUSCH”), and Physical Sidelink Shared Channel (“PSSCH”). The relationship between the sensing beam and the transmit beam that initiated the COT using the cat 4 LBT is defined using the QCL type D assumption. The sensing beam initiated by using cat 4 LBT can cover one or more transmit beams used for transmission in the COT, where WS adjustment is applied to the beam that initiated the COT.

[0105] According to a first implementation of the first solution, the CWS adjustment of the TX beam / panel (or alternatively, on the Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state of the PDSCH) at gNB 210 depends on (1) HARQ-ACK / NACK feedback and (2) the channel access priority class (“CAPC”) associated with the PDSCH. Note that the determination of the CWS adjustment depends on the TX beam / panel (or the spatial filter, spatial setting, spatial relationship, or TCI state of the PDSCH) for which the HARQ-ACK / NACK feedback report was generated. Here, the CWS adjustment does not depend on the RX beam / panel (or spatial filter, spatial setting, spatial relationship, or TCI state) for which the PUSCH carrying the HARQ-ACK / NACK feedback report is received by the PUCCH or UCI.

[0106] Using the HARQ-ACK / NACK feedback report, the gNB 210 determines the CWS adjustment for the TX beam / panel (or alternatively: spatial filter, spatial setup, spatial relationship, and / or TCI state) for the PDSCH involved in the HARQ-ACK / NACK feedback. In one embodiment, if an ACK is detected (e.g., corresponding to one or more PDSCHs in the reference duration for the latest DL transmission burst), the gNB 210 sets the CWS for the TX beam / panel to the minimum of CAPC (denoted as 'CW'). min Otherwise, (for example, if a NACK is detected as corresponding to (one or more) PDSCHs during the reference duration), the gNB 210 will increase the CWS for the TX beam / panel to the next allowed value in the priority class. If no HARQ-ACK report is generated or transmitted during the reference duration, the CWS value remains unchanged.

[0107] In one embodiment, the next allowed value is determined using the following minimum function: min((CW×2),CW max Here, CW represents the current size of the contention window and CWmax represents the maximum allowed CWS. Note that the values ​​of CWmin and CWmax can be defined based on the CAPC associated with the PDSCH transmission.

[0108] According to the second implementation of the first solution, the CWS adjustment of the TX beam / panel (or alternatively, the Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state of the PUSCH) at UE 205 depends on (1) HARQ-ACK / NACK feedback and (2) CAPC associated with the PUSCH. Note that the determination of the CWS adjustment depends on the TX beam / panel (or the spatial filter, spatial setting, spatial relationship, or TCI state of the PUSCH) for which the HARQ-ACK / NACK report was generated, and not on the RX beam / panel (or spatial filter, spatial setting, spatial relationship, or TCI state) for which the HARQ feedback was received.

[0109] Using the corresponding HARQ process ID or downlink feedback information (“DFI”), UE205 determines the CWS adjustment for the TX beam / panel (or alternatively: spatial filter, spatial setting, spatial relationship, and / or TCI state) of the PUSCH involved in the transmission of the NDI. Note that the uplink grant corresponding to the transition NDI for the HARQ process (compared to its last state) is for new data (new transmission), thus implicitly signaling that the previous data transmission (i.e., PUSCH) corresponding to the HARQ process ID or DFI was successfully received (and decoded). In contrast, the uplink grant corresponding to the non-transition NDI for the HARQ process (compared to its last state) is for the same data (retransmission), thus implicitly signaling that the previous data transmission (i.e., PUSCH) corresponding to the HARQ process ID or DFI was not successfully received and / or decoded.

[0110] In one embodiment, if a transition NDI or ACK is detected (e.g., corresponding to one or more PUSCHs in the reference duration for the latest UL transmission burst), UE 205 sets the CWS for the TX beam / panel to the minimum of CAPC (denoted as 'CWmin'). Otherwise, (e.g., if no transition NDI or NACK is detected corresponding to one or more PUSCHs in the reference duration), UE 205 increases the CWS for the TX beam / panel to the next allowed value in the priority class.

[0111] As mentioned above, the next allowed value can be determined using the following minimum function: min((CW×2),CW max Here, CW represents the current size of the contention window and CWmax represents the maximum allowed CWS. Note that the values ​​of CWmin and CWmax can be defined based on the CAPC associated with the PDSCH transmission.

[0112] According to the third implementation of the first solution, the CWS adjustment for the TX beam / panel (or alternatively, the Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state of the PUSCH) at UE 205 depends on (1) whether the (directional) PUSCH transmission is successfully received (and decoded) and (2) the CAPC associated with the PUSCH. Note that the determination of the CWS adjustment depends on the TX beam / panel (or the spatial filter, spatial setting, spatial relationship, or TCI state of the PUSCH) for which a HARQ-ACK / NACK report was generated. Again, the determination of the CWS adjustment does not depend on the RX beam / panel (or spatial filter, spatial setting, spatial relationship, or TCI state) for which HARQ feedback is received.

[0113] In the third implementation, the PUSCH transmission can be a configured licensed (“CG”) transmission (e.g., allowing unlicensed UL transmissions, i.e., a non-dynamic, semi-persistent allocation of UL resources without a licensed transmission). The HARQ structure for the CG transmission can be timer-based. Here, UE 205 starts a CG retransmission timer (e.g., cg-RetransmissionTimer) for the HARQ process ID when making a CG transmission (i.e., in the absence of an LBT failure indication). If the HARQ process receives a DFI (e.g., ACK or NACK), UE 205 stops the CG retransmission timer. Note that UE 205 can adjust the CWS based on the DFI as described above.

[0114] However, when the CG retransmission timer for the HARQ process ID expires, UE 205 considers the CG transmission unsuccessful and increments the CWS for the Tx beam / panel / spatial filter / spatial setting / spatial relationship / TCI state associated with the corresponding PUSCH, i.e., increments it to the next allowed value. In one embodiment, the next allowed value is determined using the following minimum function: min((CW×2),CW max Again, CW represents the current size of the contention window and CWmax represents the maximum allowed CWS. If the UE receives an ACK before the timer expires, CWS is set to CWmin.

[0115] According to the fourth implementation of the first solution, the CWS adjustment of the Tx beam / panel (or alternatively, the Tx spatial filter, TX spatial setting, Tx spatial relationship, and / or TCI state of the PSSCH) at the transmit-side link UE 205 (“TX UE”) depends on (1) HARQ feedback and (2) CAPC associated with the PSSCH transmission. Again, the determination of the CWS adjustment depends on the TX beam / panel (or the spatial filter, spatial setting, spatial relationship, or TCI state of the PSSCH) for which the HARQ-ACK / NACK report was generated, and not on the RX beam / panel (or the spatial filter, spatial setting, spatial relationship, or TCI state of the PFSCH) for which the HARQ feedback was received.

[0116] In some embodiments, the receive-sidelink UE 205 (“RX UE”) is configured with a public-only NACK resource, referred to as (sidelink) HARQ option 1. In other embodiments, the RX UE is configured with a dedicated ACK / NACK resource, referred to as (sidelink) HARQ option 2.

[0117] For the corresponding source-destination ID or HARQ process, using PSFCH reception (i.e., NACK based on HARQ option 1, ACK / NACK based on HARQ option 2), the TX UE determines the CWS adjustment for the TX beam / panel (or alternatively: spatial filter, spatial setting, spatial relation, and / or TCI state) involved in the transmission of the PSSCH. If an ACK is detected (e.g., corresponding to one or more PSSCHs in the reference duration for the latest SL transmission burst), the TX UE sets the CWS for the TX beam / panel to CWmin. Note that for HARQ option 1, if no NACK is received, the TX UE considers the PSSCH to have been successfully received and therefore sets the CWS to CWmin.

[0118] Otherwise, if a NACK is detected as corresponding to one or more PSSCHs during the reference duration, the TXUE increases the CWS used for the Tx beam / panel (or PSSCH spatial filter, or spatial setup, or spatial relation, or TCI state) to the next permissible value. In one embodiment, the next permissible value is determined using a minimum function: min((CW×2),CW max ), where CW represents the current size of the competition window and CWmax represents the maximum allowed CWS.

[0119] According to the fifth implementation of the first solution, m is used for the Tx beam / panel (or spatial filter, or spatial setup, or spatial relationship, or TCI state of the data channel). p The values ​​of CWmin and CWmax mentioned above depend on the CAPC associated with data transmission (e.g., PUSCH, PDSCH, or PSSCH). In one embodiment, the next allowed value is determined using a minimum function: min((CW×2), CW... max CW represents the current size of the contention window, and CWmax represents the maximum allowed CWS according to CAPC. Table 1 below provides exemplary values ​​for CWmin and CWmax for a set of channel access priority classes.

[0120] Table 1

[0121]

[0122] According to the sixth implementation of the first solution, the aforementioned principles for CWS adjustment of PUSCH transmission can also be applied to UCI on PUSCH (or PUSCH-only transmission without UL-SCH). Although PUSCH is used as an example, in general, the same process also applies to control information transmitted on PUSCH, such as UCI on PUSCH or PUSCH / UCI without UL-SCH data. As mentioned above, CWS adjustment of the TX beam / panel (or alternatively, the Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI status of the PUSCH) depends on the HARQ-ACK / NACK feedback for PUSCH transmission, and not on the RX beam / panel (or the spatial filter, spatial setting, spatial relationship, or TCI status of the PDCCH) receiving the HARQ feedback.

[0123] According to the seventh implementation of the first solution, alternatively, for the TX beam / panel, a CW reset procedure during the reference duration is applied to the Tx space filter, Tx space setting, Tx space relationship, and / or TCI state of the data channel or control channel. The CW reset procedure is described using the following rules.

[0124] If CW p =CW max,p This is used to adjust CW p The next higher allowable value is CW. max，p Number CW p =CW max，p It is used for tracking, and if CW p =CW max，p Used K times consecutively for N init The generation of [the code] is only for CW. p =CW max,p Used K times consecutively for N init The priority class p generated by CW p Reset to CW min,p In various embodiments, the value of K is selected by UE 205 from the set of values ​​{1,2,…,8} for each priority class p∈{1,2,3,4}.

[0125] According to the eighth implementation of the first solution, the CWS adjustment process includes setting the CWS to CWmin of CAPC p for a reference duration for the Tx spatial filter, Tx spatial setting, Tx spatial relation, and / or TCI state of the data or control channel when at least one HARQ feedback is reported as ACK. As mentioned above, the ACK indication can be received in the PUCCH, in the UCI on the PUSCH, or in the PSFCH. Alternatively, the ACK indication can be a converted NDI received in the DCI or SCI, or the PDSCH being correctly decoded, or the PUSCH being correctly decoded, or the PSSCH being appropriately decoded.

[0126] According to an embodiment of the second solution, when UE 205 has ongoing UL transmission using the first TX beam / panel (or alternatively, in terms of Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state), UE 205 initiates a second LBT procedure using the second TX beam / panel (or alternatively, in terms of Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state). Note that once the LBT is successful, the second LBT procedure can transmit data with a different channel access priority class (and therefore a different CWS value).

[0127] In the second solution, UE 205 may initiate one or more second LBT procedures on a set of TX beams / panels—or alternatively, on the Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state of the PUSCH (e.g., where the set is indicated by gNB 210). Here, multiple second LBT procedures can be performed in a time-sequential manner, also known as time-division multiplexing (“TDM”). Alternatively, multiple second LBT procedures can be performed simultaneously (also known as in parallel). As described above, when UE 205 has an ongoing UL transmission using a first beam / panel (or Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state), one or more second LBT procedures are performed using one or more second Tx beams / panels—or alternatively, on the Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state.

[0128] According to the first implementation of the second solution, the CWS adjustment for each of the first TX beam / panel and the second TX beam / panel (or alternatively, in terms of Tx spatial filter, Tx spatial setting, Tx spatial relationship and / or TCI state) is performed independently for each beam / panel (or Tx spatial filter, Tx spatial setting, Tx spatial relationship and / or TCI state) based on the CAPC value used when performing the corresponding LBT or received in the corresponding UL license.

[0129] In some embodiments, the generated TB can be transmitted in either the first or second Tx beam / panel (or Tx spatial filter, Tx spatial setting, Tx spatial relationship and / or TCI state), and whichever Tx beam / panel has a minimum CWS for transmission at the start of the LBT process (i.e., idle channel assessment).

[0130] In some embodiments, UE 205 may prioritize the channel access procedure for one or more UL transmissions associated with a TX beam / panel (or alternatively, in terms of Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state) according to the order of their corresponding CWS. For example, UE 205 may sort the TX beams / panels in ascending order, starting with the TX beam / panel currently having the smallest CWS. More specifically, UE 205 may prioritize the channel access procedure according to the order of CWS when UE 205 cannot perform LBT in parallel for different beams / panels (or Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state). In such embodiments, UE 205 may perform one or more UL transmissions (e.g., transmit the generated TB) using whichever TX beam / panel (or Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state) is associated with the earliest successful channel access procedure / LBT.

[0131] According to the second implementation of the second solution, the CWS adjustment process for multiple Tx beams / Tx beams / panels (or alternatively, multiple Tx spatial filters, Tx spatial settings, Tx spatial relationships and / or TCI states) is performed independently for each Tx beam / panel (or Tx spatial filter, Tx spatial setting, Tx spatial relationship and / or TCI state) based on the CAPC value used when performing LBT.

[0132] According to the third implementation of the second solution, for cases where UE 205 does not support multiple simultaneous LBT processes using a single (identical) TX beam / panel (or Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state) for the first LBT and the second LBT within the same time period, UE 205 can stop the first LBT process to start the second LBT process based on the priority of the generated TB, i.e., based on the TB priority derived from (one or more) LCHs or based on the CAPC priority. In one example, UE 205 can skip UL authorization when it decides to stop the first LBT process to start the second LBT process.

[0133] According to an embodiment of the third solution, the contention window size can be adjusted for directional transmissions of control channels such as PUCCH. Here, the determination of the contention window size adjustment for Tx beams / panels—or alternatively, for Tx spatial filters, Tx spatial settings, Tx spatial relationships, and / or TCI states of PUCCH transmission—can be based on the channel access priority class (P1) of the PUCCH and / or on the PUCCH reception state at gNB 210. In the third embodiment, it is assumed that the CWS adjustment for the PUCCH is performed independently per panel / beam. In some embodiments, PUCCH reception failure is based on the loss of aggregated / bundled HARQ feedback reports.

[0134] In various embodiments, UE 205 performs LBT on a set of panels—or alternatively, on Tx spatial filters, Tx spatial settings, Tx spatial relationships, and / or TCI states—either in a time-sequential manner (i.e., TDM mode) or simultaneously (i.e., parallel LBT). The set is indicated by gNB 210. Once the LBT is successful, UE 205 transmits a PUCCH in one or more TX panels / beams / spatial filters.

[0135] In some embodiments, MAC CE or any other L1 / L2 signaling can be used to configure / activate multiple Tx spatial filters for PUCCH transmission of UE 205. In some embodiments, each spatial filter pair used for PUCCH transmission may be different, such as SSB, CSI-RS, PDCCH / CORESET, etc. In various embodiments, UE 205 may transmit PUCCH using the same spatial filter configuration for each beam / panel. Here, it is possible to configure the same or different PUCCH resources for UE 205 on a per Tx beam / panel basis—or alternatively, on the Tx spatial filters, Tx spatial settings, Tx spatial relationships, and / or TCI states of the PUCCH.

[0136] According to the first implementation of the third solution, UE 205 detects aggregated ACK to NACK (and / or ACK to DTX) errors and NACK to ACK (and / or NACK to DTX) errors by monitoring the NDI field in the DCI for the corresponding HARQ process ID associated with the HARQ report transmitted in the PUCCH (or in the UCI on the PUSCH).

[0137] In various embodiments, UE 205 transmits a HARQ feedback report in the PUCCH when the LBT / CCA is successful (either a Tx beam / panel, Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state). In one case, PUCCH decoding can succeed at gNB 210, while in another case, PUCCH decoding failure or DTX may occur at gNB 210. Based on the interpretation of the decoded HARQ report (e.g., whether the HARQ report is (A) not received and / or incorrectly decoded or (B) correctly decoded), gNB 210 transmits an unconverted NDI (i.e., indicating retransmission) and / or a converted NDI (i.e., indicating new transmission) for the corresponding HARQ process.

[0138] In the first implementation of the third solution, NDIs (e.g., a counter of the number of NDI transitions for a HARQ process) from subsequent DCI receptions are accumulated until the next PUCCH opportunity for the same beam / panel (or Tx spatial filter, Tx spatial setting, Tx spatial relationship, and / or TCI state) used for PUCCH transmission with a HARQ report, and compared with the corresponding HARQ report transmitted in the PUCCH (e.g., a counter of the number of ACKs in the HARQ report). A direct comparison between the received NDIs and the HARQ feedback reports transmitted for the corresponding HARQ process determines the PUCCH decoding status and the presence of errors, and these errors are compared against a configured threshold to determine CWS adjustments.

[0139] If the UE 205 detects these errors below the configured threshold, the CWS for Tx beam / panel (or Tx spatial filter, Tx spatial settings, Tx spatial relationships, and / or TCI status) is set to CW. min .

[0140] If UE 205 detects that these errors exceed the threshold, then the corresponding CWS of the Tx beam / panel (instead, the corresponding spatial filter / spatial setting / spatial relationship / TCI state) will be increased by UE 205 to the next allowed value in the priority class or increased to the value CW. next =min((CW current ×2), CW max ).

[0141] • If UE 205 detects during the ongoing reference duration that one of the received feedbacks is above the error threshold, or receives a converted NDI for an Ack feedback sent earlier for the HARQ process, then CWS is reset.

[0142] • If UE 205 does not transmit feedback during the reference duration, the CWS remains unchanged.

[0143] According to the second implementation of the third solution, UE 205 can monitor the DAI value in the DCI during subsequent receptions and determine the reception status of the PUCCH by comparing the DAI value from subsequent DCI receptions (e.g., DCI-2 format) with the previous transmission reported in the HARQ in the PUCCH.

[0144] Figure 3 This diagram illustrates an embodiment of UE 205 determining the reception status of PUCCH according to a second implementation of the third solution. As shown, UE 205 determines the reception status of PUCCH by comparing the DAI value from subsequent DCI 2 receptions with the previous transmissions of the HARQ report in the PUCCH.

[0145] According to the third implementation of the third solution, gNB 210 can determine the reception status of the PUCCH by comparing the decoding status of the HARQ feedback from the PUCCH with the DAI value transmitted in the previous DCI. gNB 210 then transmits an explicit indication to UE 205. In some embodiments, code points in the DCI (or MAC CE) are used to explicitly inform UE 205 about CWS adjustments for the Tx spatial filter, Tx spatial settings, Tx spatial relationships, and / or TCI status of the PUCCH for the Tx beam / panel. In the first example, the code points can be interpreted as follows:

[0146] • The bit value “00” indicates that the CWS will be set to the CWS corresponding to each priority class p∈{1,2,3,4}. min

[0147] • The value “01” indicates that CWS will be incremented to the next allowed value in the priority class, for example, using the minimum function: CWnext =min((CW current ×2), CW max )

[0148] • A value of “10” indicates that the CWS will be reset (CWS only). p =CW max,p Used K times consecutively for N init The generated priority class p, CW p Reset to CW min,p Note that K is selected by eNB / gNB from the set of values ​​{1,2,…,8} for each priority class p∈{1,2,3,4}.

[0149] • The value “11” indicates that CWS will remain the same (i.e., CWS will not change) – CWS remains unchanged if the UE does not generate a HARQ-ACK report or transmit HARQ feedback.

[0150] In some embodiments, the terms antenna, panel, and antenna panel are used interchangeably. An antenna panel can be hardware used to transmit and / or receive radio signals at frequencies below 6 GHz (e.g., frequency range 1 (“FR1”, i.e., frequencies from 410 MHz to 7125 MHz)) or above 6 GHz (e.g., FR2) or millimeter wave (mmWave). In some embodiments, the antenna panel may include an array of antenna elements, wherein each antenna element is connected to hardware such as a phase shifter that allows a control module to apply spatial parameters for signal transmission and / or reception. The resulting radiation pattern may be referred to as a beam, which may or may not be single-mode and may allow the device to amplify signals transmitted or received from a spatial direction.

[0151] In some embodiments, antenna panels may or may not be virtualized as antenna ports in the specification. Antenna panels can be connected to the baseband processing module via radio frequency (“RF”) chains for each of the transmit (egress) and receive (ingress) directions. The device’s capabilities regarding the number of antenna panels, their duplex capabilities, their beamforming capabilities, etc., may or may not be transparent to other devices. In some embodiments, capability information may be transmitted via signaling, or in some embodiments, capability information may be provided to the device without signaling. Where such information is available to other devices, it can be used for signaling or local decision-making.

[0152] In some embodiments, the device (e.g., UE 205 or gNB 210) antenna panel may be a physical or logical antenna array comprising a collection of antenna elements or antenna ports sharing a common or significant portion of an RF chain (e.g., in-phase / quadrature (“I / Q”) modulator, analog-to-digital (“A / D”) converter, local oscillator, phase-shifting network). The device antenna panel, or “device panel,” may be a logical entity to which physical device antennas are mapped. The mapping from physical device antennas to logical entities may be determined by the device implementation.

[0153] Communication (receive or transmit) on at least a subset of the antenna elements or antenna ports (also referred to herein as active elements) of the antenna panel for radiating energy requires biasing or energizing the RF chain, which results in current depletion or power consumption in the devices associated with the antenna panel (including power consumption of the power amplifiers / low-noise amplifiers (“LNAs”) associated with the antenna elements or antenna ports). The phrase “active for radiating energy” as used herein is not intended to be limited to transmitting functionality but also includes receiving functionality. Therefore, the antenna elements active for radiating energy can be coupled simultaneously or sequentially to a transmitter to transmit RF energy or to a receiver to receive RF energy, or generally to a transceiver to perform their intended functionality. Communication on the active elements of the antenna panel enables the generation of radiation patterns or beams.

[0154] In some embodiments, depending on the device's own implementation, the "device panel" can have at least one of the following functionalities as an antenna group unit for independently controlling its Tx beam, an antenna group unit for independently controlling its transmission power, and an antenna group unit for independently controlling its transmission timing. The "device panel" of UE 205 can be transparent to gNB 210. Under certain conditions, gNB 210 or the network can assume that the mapping between the device's physical antennas and the logical entity "device panel" will not change. For example, the conditions may include until the next update or report from the device or include a duration during which gNB 210 assumes the mapping will not change. The device can report its capabilities relative to the "device panel" to gNB 210 or the network. Device capabilities may include at least the number of "device panels". In one implementation, the device can support UL transmission from one beam within the panel; in the case of multiple panels, more than one beam (one beam per panel) can be used for UL transmission. In another implementation, more than one beam per panel can support / be used for UL transmission.

[0155] In some of the described embodiments, an antenna port is defined such that a channel on which a symbol on the antenna port is transmitted can be inferred from a channel on which another symbol on the same antenna port is transmitted.

[0156] Two antenna ports are considered quasi-co-located (QCL) if the large-scale properties of a channel transmitting symbols from one antenna port can be inferred from the channel transmitting symbols from the other antenna port. Large-scale properties include one or more of delay spread, Doppler spread, Doppler shift, average gain, average delay, and spatial Rx parameters. Two antenna ports can be quasi-co-located relative to a subset of large-scale properties, and different subsets of large-scale properties can be indicated by the QCL type. For example, qcl-Type can take one of the following values:

[0157] • "QCL-TypeA": {Doppler frequency shift, Doppler spread, average delay, delay spread}

[0158] • "QCL-TypeB": {Doppler frequency shift, Doppler spread}

[0159] • "QCL-TypeC": {Doppler shift, average delay}

[0160] • “QCL-TypeD”: {space Rx parameter}.

[0161] Spatial Rx parameters may include one or more of the following: angle of arrival (“AoA”), main AoA, average AoA, angular spread, power angular spectrum of AoA (“PAS”), average departure angle (“AoD”), PAS of AoD, transmit / receive channel correlation, transmit / receive beamforming, spatial channel correlation, etc.

[0162] According to embodiments, an "antenna port" can be a logical port, which may correspond to a beam (generated by beamforming) or a physical antenna on the device. In some embodiments, a physical antenna can be directly mapped to a single antenna port, where the antenna port corresponds to an actual physical antenna. Alternatively, after applying complex weights, cyclic delays, or both to the signal on each physical antenna, a physical antenna or an antenna set or an antenna array or a set or subset of antenna subarrays can be mapped to one or more antenna ports. A physical antenna set can have antennas from a single module or panel, or from multiple modules or multiple panels. Weights can be fixed, as in antenna virtualization schemes such as cyclic delay diversity (CDD). The process for deriving an antenna port from a physical antenna can be specific to the device implementation and transparent to other devices.

[0163] In some of the described embodiments, the TCI state associated with the target transmission can indicate parameters for configuring the quasi-co-location relationship between the target transmission (e.g., the target RS of the DM-RS port of the target transmission during transmission timing) and one or more source reference signals (e.g., SSB / CSI-RS / SRS) relative to one or more quasi-co-location type parameters indicated in the corresponding TCI state. The device is capable of receiving configurations of multiple transmission configuration indicator states for the serving cell to enable transmission on the serving cell.

[0164] In some of the described embodiments, spatial relation information associated with the target transmission can indicate parameters for configuring the spatial settings between the target transmission and a reference RS (e.g., SSB / CSI-RS / SRS). For example, the device can transmit the target transmission using the same spatial domain filter used for receiving the reference RS (e.g., a DLRS such as an SSB / CSI-RS). In another example, the device can transmit the target transmission using the same spatial domain transmission filter used for transmitting the reference RS (e.g., a UL RS such as an SRS). The device is capable of receiving configurations for multiple spatial relation information configurations for the serving cell to enable transmission on the serving cell.

[0165] Figure 4 The LBT process 400 for a radio frame 405 for unlicensed communication according to an embodiment of the present disclosure is depicted. When the communication channel is a wide-bandwidth unlicensed carrier 410 (e.g., several hundred megahertz), the CCA / LBT process depends on the energy levels on multiple subbands 415 of the detected communication channel, such as... Figure 4 As shown in the diagram. LBT parameters (such as type / duration, idle channel assessment parameters, etc.) are configured in UE 205 by a RAN node such as gNB 210. In one embodiment, the LBT procedure is performed at PHY layer 230. When performing an omnidirectional LBT, the entity (i.e., gNB 210 or UE 205) can use an omnidirectional sensing beam. Alternatively, the entity can simultaneously use multiple beams (i.e., corresponding to multiple device panels) to perform directional LBT to simulate omnidirectional sensing. When performing a directional LBT, the entity (i.e., gNB 210 or UE 205) performs LBT for a given beam (i.e., corresponding to a given spatial direction). Note that each directional beam may correspond to one or more device panels.

[0166] Figure 4The frame structure of radio frame 405 for unlicensed communication between UE 205 and gNB 210 is also depicted. Radio frame 405 can be divided into subframes (indicated by subframe boundary 420) and can be further divided into time slots (indicated by time slot boundary 425). Radio frame 405 uses a flexible arrangement in which uplink and downlink operation are on the same frequency channel but are separated in time. However, subframes are not configured as downlink subframes or uplink subframes, and a particular subframe can be used by either UE 205 or gNB 210. As previously discussed, LBT is performed before transmission. In the event of a misalignment between LBT and time slot boundary 425, a reservation signal 430 can be transmitted to reserve (i.e., occupy) the channel until the time slot boundary is reached and data transmission begins.

[0167] Figure 5 User equipment device 500, which can be used to adjust the size of a competing window according to embodiments of the present disclosure, is depicted. In various embodiments, user equipment device 500 is used to implement one or more of the solutions described above. User equipment device 500 may be an embodiment of the remote unit 105 and / or UE 205 described above. Furthermore, user equipment device 500 may include processor 505, memory 510, input device 515, output device 520, and transceiver 525.

[0168] In some embodiments, input device 515 and output device 520 are combined into a single device, such as a touchscreen. In some embodiments, user equipment device 500 may not include any input device 515 and / or output device 520. In various embodiments, user equipment device 500 may include one or more of the following: processor 505, memory 510, and transceiver 525, and may not include input device 515 and / or output device 520.

[0169] As depicted, transceiver 525 includes at least one transmitter 530 and at least one receiver 535. In some embodiments, transceiver 525 communicates with one or more cells (or radio coverage areas) supported by one or more base station units 121. In various embodiments, transceiver 525 may operate on unlicensed spectrum. Furthermore, transceiver 525 may include multiple UE panels supporting one or more beams. Additionally, transceiver 525 may support at least one network interface 540 and / or application interface 545. One or more application interfaces 545 may support one or more APIs. One or more network interfaces 540 may support 3GPP reference points such as Uu, N1, PC5, etc. Other network interfaces 540 may be supported, as will be understood by those skilled in the art.

[0170] In one embodiment, processor 505 may include any known controller capable of executing computer-readable instructions and / or performing logical operations. For example, processor 505 may be a microcontroller, microprocessor, central processing unit (“CPU”), graphics processing unit (“GPU”), auxiliary processing unit, field-programmable gate array (“FPGA”), or similar programmable controller. In some embodiments, processor 505 executes instructions stored in memory 510 to perform the methods and routines described herein. Processor 505 is communicatively coupled to memory 510, input device 515, output device 520, and transceiver 525. In some embodiments, processor 505 may include an application processor (also referred to as a “main processor”) that manages application domain and operating system (“OS”) functions, and a baseband processor (also referred to as a “baseband radio processor”) that manages radio functions.

[0171] In various embodiments, processor 505 controls user equipment apparatus 500 to implement the UE behavior described above. For example, transceiver 525, in response to a successful LBT procedure, initiates a first channel occupancy using at least one transmit beam / panel and transmits directional transmissions using a first transmit beam / panel selected from a plurality of transmit beams / panels. Note that while the user equipment apparatus is described in terms of performing the LBT procedure against a “set of transmit panels,” in other embodiments, LBT may be performed against a “set of transmit beams.” As used herein, the term “beam / panel” (or similar notation) indicates that the description applies to Tx beams and / or panels. Additionally, the description of beams and / or panels also applies to Tx spatial filters, Tx spatial settings, Tx spatial relationships, and / or TCI states.

[0172] Furthermore, note that the LBT process is performed using a sensing beam / panel different from the transmit beam / panel. In one embodiment, there is a one-to-one mapping between the sensing beam / panel and the transmit beam / panel. Here, the transmit beam / panel and its corresponding sensing beam / panel have a QCL type D assumption. In another embodiment, there is a one-to-many mapping between the sensing beam / panel and the transmit beam / panel. Here, multiple transmit beams / panels and sensing beams / panels have a QCL type D assumption.

[0173] Processor 505 determines whether the directional transmission was successfully received by the receiver and updates the first contention window size (“CWS”) specific to the first transmit beam / panel, wherein a separate CWS is maintained for each transmit beam / panel that initiated the first channel occupancy. When there is a one-to-one relationship between the sensing beam / panel and the transmit beam / panel, the first CWS applies to the transmit beam that shares the QCL type D assumption with the sensing beam. However, when there is a one-to-many relationship between the sensing beam / panel and the transmit beam / panel, the first CWS applies to each transmit beam that shares the QCL type D assumption with the sensing beam.

[0174] In some embodiments, updating the first CWS includes: (A) adjusting the CWS to the next allowed value (e.g., selected from a predefined set of values) in response to determining that the directed transmission was not successfully received by the receiver, and (B) setting the first CWS to a minimum value in response to determining that the directed transmission was successfully received by the receiver. The processor 505 uses the updated first CWS to perform subsequent LBT procedures before using subsequent directed transmissions of the first transmit beam / panel.

[0175] In some embodiments, determining whether a directional transmission has been successfully received by the receiver includes: using a first receive beam / panel to receive HARQ feedback corresponding to the directional transmission. In such embodiments, updating the first CWS depends on the HARQ feedback (e.g., ACK or NACK) generated for the first transmit beam / panel, wherein updating the CWS does not depend on the first receive beam / panel (i.e., not on the beam carrying the HARQ-ACK feedback for the data channel). As an example, the directional transmission may be a PUSCH transmission, where the CWS adjustment does not depend on the received receive beam / panel, e.g., a PDCCH carrying HARQ feedback for the PUSCH transmission. As another example, the directional transmission may be a PSSCH transmission, where the CWS adjustment does not depend on the received receive beam / panel, e.g., a PSFCH carrying HARQ feedback for the PSSCH transmission.

[0176] In some embodiments, directed transmission includes data transmission on a sidelink channel (e.g., PSSCH) in which a common HARQ-NACK feedback resource (i.e., PSFCH option 1) is configured. In such embodiments, the absence of negative HARQ feedback corresponding to the directed transmission (i.e., the absence of HARQ-NACK) indicates that the directed transmission has been successfully received by the receiver, such that updating the first CWS includes setting the first CWS to a minimum value in response to detecting the absence of HARQ-NACK feedback.

[0177] In some embodiments, the received HARQ feedback includes multiple feedback responses. In such an embodiment, determining that the directed transmission was successfully received by the receiver in response to at least one of the multiple feedback responses being an affirmative response (i.e., ACK) such that updating the first CWS includes setting the first CWS to a minimum value in response to at least one of the multiple feedback responses being an affirmative response.

[0178] In some embodiments, determining whether a directed transmission was successfully received by the receiver includes receiving the NDI and determining whether the directed transmission was successful based on the NDI. In some embodiments, an NDI that is switched compared to a previous state indicates that the directed transmission was successfully received by the receiver, while an NDI that is not switched compared to a previous state indicates that the directed transmission was not successfully received by the receiver. A “switching” means that the bit value is switched (compared to its previous state), so if its previous value was “1” and its current value is “0”, then the NDI will be considered “switched”. Conversely, if its current value is “1” and its previous value was also “1”, then the NDI will be considered “unswitched”.

[0179] In some embodiments, determining whether a directed transmission has been successfully received by the receiver includes detecting the expiration of a retransmission timer (i.e., a CG retransmission timer) for the HARQ process corresponding to the directed transmission. In such embodiments, the expiration of the retransmission timer indicates that the directed transmission has not been successfully received by the receiver.

[0180] In some embodiments, a directed transmission is associated with a first CAPC, wherein the CWS value is based on the first CAPC, and the method further includes maintaining a separate set of CWS values ​​for each of a plurality of CAPCs, the plurality of CAPCs including the first CAPC. In some embodiments, the directed transmission includes a UCI transmitted on a data channel (i.e., PUSCH). In such embodiments, updating the first CWS depends on a HARQ feedback generated for the data channel.

[0181] In some embodiments, adjusting the first CWS to the next allowed value includes increasing the first CWS according to the function: min(CW×2+1, CWmax), where the value "CW" represents the current value CWS of the first CWS, the value "CWmax" represents the maximum value used for the first CWS, and the function selects the minimum of two candidate values. In some embodiments, the processor 505 tracks the number of times the first CWS is used when the first transmit beam / panel is at its maximum value. In such embodiments, if the first CWS is the maximum value, the next allowed value is the maximum value until a threshold usage number is reached, whereby, in response to reaching the threshold usage number, the first CWS is reset to the minimum value used for the first transmit beam / panel. In some embodiments, updating the first CWS includes maintaining the current value of the first CWS. In a further embodiment, the minimum value of the first CWS (i.e., "CWmin") and the maximum value of the first CWS (i.e., "CWmax") are based on the CAPC of directional transmission.

[0182] In some embodiments, processor 505 executes a second LBT procedure to initiate a second channel occupancy, different from the first channel occupancy, for the second transmit beam / panel while directional transmission using the first transmit beam / panel is in progress. In such embodiments, the transmitter may transmit data TB using the transmit beam / panel with the lowest CWS, selected from the first and second transmit beam / panels, at the start of the LBT (i.e., CCA) procedure. In some embodiments, processor 505 stops the ongoing directional transmission using the first transmit beam / panel in response to the start of the second LBT procedure. In a further embodiment, the second CWS corresponding to the second transmit beam / panel is adjusted independently of the first CWS based on the CAPC value used when executing the LBT procedure.

[0183] In various embodiments, processor 505 performs an LBT process on the set of transmit beams / panels. As described above, the LBT process can be performed sequentially (i.e., in a TDM manner) or in parallel. Additionally, in response to a successful LBT on a transmit beam / panel, processor 505 performs a PUCCH transmission on at least one beam / panel in the set of transmit beams / panels and determines whether the PUCCH transmission was successfully received by the RAN node (e.g., gNB 210). Processor 505 updates the CWS corresponding to each beam / panel used in the PUCCH transmission, wherein a separate CWS is maintained for each transmit beam / panel.

[0184] In some embodiments, updating each CWS includes: (A) adjusting the CWS to the next allowed value (e.g., selected from a predefined set of values) in response to determining that a PUCCH transmission using the corresponding transmit beam / panel was not successfully received by the RAN node, and (B) setting the CWS to the minimum value in response to determining that a PUCCH transmission was successfully received by the RAN node.

[0185] In some embodiments, processor 505 receives (i.e., via transceiver 525) multiple NDIs corresponding to multiple HARQ processes in a PUCCH transmission, and determines a HARQ feedback error rate based on the multiple NDIs and HARQ feedback reported in the PUCCH transmission. In such an embodiment, in response to the HARQ feedback error rate being below a threshold, it is determined that the PUCCH transmission has been successfully received by the RAN node, such that if the HARQ feedback error rate is below the threshold, the CWS of each beam / panel used in the PUCCH transmission is set to a minimum value (i.e., "CWmin").

[0186] In some embodiments, processor 505 receives a set of DAI values ​​corresponding to a PUCCH transmission. In such embodiments, determining whether a PUCCH transmission was successfully received by the RAN node includes comparing the set of DAI values ​​with HARQ feedback reported in the PUCCH transmission. In some embodiments, determining whether a PUCCH transmission was successfully received by the RAN node includes receiving a CWS adjustment indicator from the RAN node. In such embodiments, updating the CWS includes adjusting the CWS value according to the adjustment indicator.

[0187] In some embodiments, adjusting each CWS to the next allowed value includes incrementing CWS according to the function: min(CW×2+1, CWmax), where the value "CW" represents the current value of CWS, the value "CWmax" represents the maximum value for CWS, and the function selects the minimum of two candidate values. In a further embodiment, the minimum value (i.e., "CWmin") and maximum value (i.e., "CWmax") of each CWS are based on the CAPC transmitted via PUCCH. In some embodiments, updating each CWS includes maintaining the current value of the CWS.

[0188] In one embodiment, memory 510 is a computer-readable storage medium. In some embodiments, memory 510 includes volatile computer storage media. For example, memory 510 may include RAM, including dynamic RAM (“DRAM”), synchronous dynamic RAM (“SDRAM”), and / or static RAM (“SRAM”). In some embodiments, memory 510 includes non-volatile computer storage media. For example, memory 510 may include a hard disk drive, flash memory, or any other suitable non-volatile computer storage device. In some embodiments, memory 510 includes both volatile and non-volatile computer storage media.

[0189] In some embodiments, memory 510 stores data related to adjusting the size of the contention window. For example, memory 510 may store various parameters, panel / beam configurations, resource assignments, strategies, etc., as described above. In some embodiments, memory 510 also stores program code and related data, such as an operating system or other controller algorithms operating on device 500.

[0190] In one embodiment, input device 515 may include any known computer input device, including a touch panel, button, keyboard, stylus, microphone, etc. In some embodiments, input device 515 may be integrated with output device 520, for example, as a touchscreen or similar touch-sensitive display. In some embodiments, input device 515 includes a touchscreen, allowing text to be entered using a virtual keyboard displayed on the touchscreen and / or by handwriting on the touchscreen. In some embodiments, input device 515 includes two or more different devices, such as a keyboard and a touch panel.

[0191] In one embodiment, output device 520 is designed to output visual, auditory, and / or tactile signals. In some embodiments, output device 520 includes an electronically controllable display or display device capable of outputting visual data to a user. For example, output device 520 may include, but is not limited to, LCD displays, LED displays, OLED displays, projectors, or similar display devices capable of outputting images, text, etc., to a user. As another non-limiting example, output device 520 may include a wearable display, such as a smartwatch, smart glasses, head-up display, etc., separate from but communicatively coupled to the rest of user equipment device 500. Furthermore, output device 520 may be a component of a smartphone, personal digital assistant, television, desktop computer, laptop computer, personal computer, vehicle dashboard, etc.

[0192] In some embodiments, output device 520 includes one or more speakers for generating sound. For example, output device 520 may generate an auditory alarm or notification (e.g., a buzzer or ring). In some embodiments, output device 520 includes one or more haptic devices for generating vibration, motion, or other haptic feedback. In some embodiments, all or part of output device 520 may be integrated with input device 515. For example, input device 515 and output device 520 may form a touchscreen or similar touch-sensitive display. In other embodiments, output device 520 may be located near input device 515.

[0193] Transceiver 525 communicates with one or more network functions of a mobile communication network via one or more access networks. Transceiver 525 operates under the control of processor 505 to transmit and receive messages, data, and other signals. For example, processor 505 may selectively activate transceiver 525 (or a portion thereof) at specific times to send and receive messages.

[0194] Transceiver 525 includes at least a transmitter 530 and at least one receiver 535. One or more transmitters 530 can be used to provide UL communication signals to base station unit 121, such as UL transmissions described herein. Similarly, as described herein, one or more receivers 535 can be used to receive DL communication signals from base station unit 121. Although only one transmitter 530 and one receiver 535 are illustrated, user equipment device 500 can have any suitable number of transmitters 530 and receivers 535. Furthermore, the transmitter(s) 530 and receiver(s) 535 can be of any suitable type. In one embodiment, transceiver 525 includes a first transmitter / receiver pair for communicating with a mobile communication network on licensed radio spectrum and a second transmitter / receiver pair for communicating with a mobile communication network on unlicensed radio spectrum.

[0195] In some embodiments, a first transmitter / receiver pair for communicating with a mobile communication network on licensed radio spectrum and a second transmitter / receiver pair for communicating with a mobile communication network on unlicensed radio spectrum may be combined into a single transceiver unit, such as a single chip performing functions for both licensed and unlicensed radio spectrum. In some embodiments, the first transmitter / receiver pair and the second transmitter / receiver pair may share one or more hardware components. For example, certain transceivers 525, transmitters 530, and receivers 535 may be implemented as physically separate components that access shared hardware and / or software resources, such as network interface 540.

[0196] In various embodiments, one or more transmitters 530 and / or one or more receivers 535 may be implemented and / or integrated into a single hardware component, such as a multi-transceiver chip, system-on-a-chip, ASIC, or other type of hardware component. In some embodiments, one or more transmitters 530 and / or one or more receivers 535 may be implemented and / or integrated into a multi-chip module. In some embodiments, other components such as network interface 540 or other hardware components / circuitets may be integrated with any number of transmitters 530 and / or receivers 535 into a single chip. In such embodiments, transmitters 530 and receivers 535 may be logically configured as transceivers 525 using a more common control signal or as modular transmitters 530 and receivers 535 implemented in the same hardware chip or multi-chip module.

[0197] Figure 6 A network device 600, which can be used to adjust the size of a contention window according to embodiments of the present disclosure, is depicted. In one embodiment, the network device 600 may be an implementation of a RAN node, such as base station unit 121 or gNB 210 as described above. Furthermore, the base station network device 600 may include a processor 605, a memory 610, an input device 615, an output device 620, and a transceiver 625.

[0198] In some embodiments, input device 615 and output device 620 are combined into a single device, such as a touchscreen. In some embodiments, network device 600 may not include any input device 615 and / or output device 620. In various embodiments, network device 600 may include one or more of the following: processor 605, memory 610, and transceiver 625, and may not include input device 615 and / or output device 620.

[0199] As depicted, transceiver 625 includes at least one transmitter 630 and at least one receiver 635. Here, transceiver 625 communicates with one or more remote units 105. Additionally, transceiver 625 may support at least one network interface 640 and / or application interface 645. The application interface(s) 645 may support one or more APIs. The network interface(s) 640 may support 3GPP reference points such as Uu, N1, N2, and N3. Other network interfaces 640 may be supported, as will be understood by those skilled in the art.

[0200] In one embodiment, processor 605 may include any known controller capable of executing computer-readable instructions and / or performing logical operations. For example, processor 605 may be a microcontroller, microprocessor, CPU, GPU, auxiliary processing unit, FPGA, or similar programmable controller. In some embodiments, processor 605 executes instructions stored in memory 610 to perform the methods and routines described herein. Processor 605 is communicatively coupled to memory 610, input device 615, output device 620, and transceiver 625.

[0201] In various embodiments, network device 600 is a RAN node (e.g., gNB 210) that transmits UE configuration and receives measurement reports, as described herein. In such embodiments, processor 605 controls network device 600 to perform the RAN actions described above. When operating as a RAN node, processor 605 may include an application processor (also referred to as a "main processor") that manages application domain and operating system ("OS") functions, and a baseband processor (also referred to as a "baseband radio processor") that manages radio functions.

[0202] In various embodiments, processor 605 controls transceiver 625 to initiate a first channel occupancy using at least one transmit beam / panel in response to a successful LBT process and to transmit directional transmissions using a first transmit beam / panel selected from a plurality of transmit beams / panels. As discussed above, the LBT process may be performed using a sensing beam / panel different from the transmit beam / panel, wherein, for example, there may be a one-to-one mapping between sensing beams / panels and transmit beams / panels, or a one-to-many mapping between sensing beams / panels and transmit beams / panels.

[0203] Processor 605 determines at the communication device whether the directed transmission has been successfully received by the receiver and updates the first CWS specific to the first transmit beam / panel, wherein a separate CWS is maintained for each transmit beam / panel that initiated the first channel occupancy. Note that while the network apparatus is described in terms of performing the LBT process for a “set of transmit panels,” in other embodiments, LBT may be performed for a “set of transmit beams.” As used herein, the term “beam / panel” (or similar notation) indicates that the description applies to Tx beams and / or panels. Additionally, the description of beams and / or panels also applies to Tx spatial filters, Tx spatial settings, Tx spatial relationships, and / or TCI states.

[0204] In one embodiment, updating the first CWS includes adjusting the first CWS to the next allowed value (e.g., selecting the CWS value from a predefined set of values) in response to determining that the directional transmission was not successfully received by the receiver. In another embodiment, updating the first CWS includes setting the first CWS to a minimum value (i.e., "CWmin") in response to determining that the directional transmission was successfully received by the receiver. The processor 605 uses the updated first CWS to perform subsequent LBT procedures before using subsequent directional transmissions of the first transmit beam / panel.

[0205] In some embodiments, determining whether a directional transmission has been successfully received by the receiver includes using a first receive beam / panel to receive HARQ feedback corresponding to the directional transmission. In such embodiments, updating the first CWS depends on the HARQ feedback (e.g., ACK or NACK) generated for the first transmit beam / panel, wherein updating the CWS does not depend on the first receive beam / panel (i.e., not on the beam carrying the HARQ-ACK feedback for the data channel). Specifically, the directional transmission may be a PDSCH transmission, wherein CWS adjustment does not depend on the receive beam / panel receiving the PUCCH (or UCI on the PUSCH) carrying the HARQ feedback for the PDSCH transmission.

[0206] In some embodiments, the received HARQ feedback includes multiple feedback responses. In such embodiments, determining that the directed transmission was successfully received by the receiver in response to at least one of the multiple feedback responses being an affirmative response (i.e., ACK) such that updating the first CWS includes setting the first CWS to a minimum value in response to at least one of the multiple feedback responses being an affirmative response.

[0207] In some embodiments, directional transmission is associated with a first CAPC, wherein the CWS value is based on the first CAPC, and the method further includes maintaining a separate set of CWS values ​​for each of a plurality of CAPCs, the plurality of CAPCs including the first CAPC.

[0208] In some embodiments, adjusting the first CWS to the next allowed value includes increasing the first CWS according to the following function: min(CW×2+1, CWmax), where the value “CW” represents the current value CWS of the first CWS, the value “CWmax” represents the maximum value used for the first CWS, and the function selects the minimum value among two candidate values.

[0209] In some embodiments, processor 605 tracks the number of times the first CWS is used when the first transmit beam / panel is at its maximum value. In such embodiments, if the first CWS is at its maximum value, the next allowed value is the maximum value until a threshold usage number is reached, wherein, in response to reaching the threshold usage number, the first CWS is reset to the minimum value used for the first transmit beam / panel. In some embodiments, updating the first CWS includes maintaining the current value of the first CWS. In further embodiments, the minimum value (i.e., "CWmin") and the maximum value (i.e., "CWmax") of the first CWS are based on CAPC for directional transmission.

[0210] In some embodiments, the processor 605 performs a second LBT process to initiate a second channel occupation, different from the first channel occupation, on the second transmit beam / panel while directional transmission using the first transmit beam / panel is in progress. In such an embodiment, the transmitter may use the transmit beam / panel with the lowest CWS to transmit a data transmission block (“TB”) at the start of the LBT (i.e., CCA) process, the transmit beam / panel being selected from the first transmit beam / panel and the second transmit beam / panel.

[0211] In some embodiments, processor 605 stops ongoing directional transmission using the first transmit beam / panel in response to initiating a second LBT process. In a further embodiment, a second CWS corresponding to the second transmit beam / panel is adjusted independently of the first CWS based on the CAPC value used during the execution of the LBT process.

[0212] In one embodiment, memory 610 is a computer-readable storage medium. In some embodiments, memory 610 includes volatile computer storage media. For example, memory 610 may include RAM, including dynamic RAM (“DRAM”), synchronous dynamic RAM (“SDRAM”), and / or static RAM (“SRAM”). In some embodiments, memory 610 includes non-volatile computer storage media. For example, memory 610 may include a hard disk drive, flash memory, or any other suitable non-volatile computer storage device. In some embodiments, memory 610 includes both volatile and non-volatile computer storage media.

[0213] In some embodiments, memory 610 stores data related to adjusting the size of the contention window. For example, memory 610 may store parameters, configurations, resource assignments, strategies, etc., as described above. In some embodiments, memory 610 also stores program code and related data, such as an operating system or other controller algorithms operating on device 600.

[0214] In one embodiment, input device 615 may include any known computer input device, including a touch panel, buttons, keyboard, stylus, microphone, etc. In some embodiments, input device 615 may be integrated with output device 620, for example, as a touchscreen or similar touch-sensitive display. In some embodiments, input device 615 includes a touchscreen, allowing text to be entered using a virtual keyboard displayed on the touchscreen and / or by handwriting on the touchscreen. In some embodiments, input device 615 includes two or more different devices, such as a keyboard and a touch panel.

[0215] In one embodiment, output device 620 is designed to output visual, auditory, and / or tactile signals. In some embodiments, output device 620 includes an electronically controllable display or display device capable of outputting visual data to a user. For example, output device 620 may include, but is not limited to, LCD displays, LED displays, OLED displays, projectors, or similar display devices capable of outputting images, text, etc., to a user. As another non-limiting example, output device 620 may include a wearable display, such as a smartwatch, smart glasses, head-up display, etc., separate from but communicatively coupled to the rest of network device 600. Furthermore, output device 620 may be a component of a smartphone, personal digital assistant, television, desktop computer, laptop computer, personal computer, vehicle dashboard, etc.

[0216] In some embodiments, output device 620 includes one or more speakers for generating sound. For example, output device 620 may generate an auditory alarm or notification (e.g., a buzzer or ring). In some embodiments, output device 620 includes one or more haptic devices for generating vibration, motion, or other haptic feedback. In some embodiments, all or part of output device 620 may be integrated with input device 615. For example, input device 615 and output device 620 may form a touchscreen or similar touch-sensitive display. In other embodiments, output device 620 may be located near input device 615.

[0217] Transceiver 625 includes at least a transmitter 630 and at least one receiver 635. As described herein, one or more transmitters 630 can be used to communicate with a UE. Similarly, as described herein, one or more receivers 635 can be used to communicate with network functions in a PLMN and / or RAN. Although only one transmitter 630 and one receiver 635 are illustrated, network device 600 can have any suitable number of transmitters 630 and receivers 635. Furthermore, transmitter(s) 630 and receiver(s) 635 can be of any suitable type.

[0218] Figure 7 An embodiment of a method 700 for adjusting the size of a contention window according to embodiments of the present disclosure is depicted. In various embodiments, method 700 is performed by a radio communication device in a mobile communication network, such as remote unit 105, base station unit 121, UE 205, gNB 210, user equipment device 500, and / or network device 600 as described above. In some embodiments, method 700 is performed by a processor, such as a microcontroller, microprocessor, CPU, GPU, auxiliary processing unit, FPGA, etc.

[0219] Method 700 initiates and, in response to a successful Listen-Before-Speak (“LBT”) procedure, uses at least one transmit beam to initiate 705 a first channel occupancy. Method 700 includes transmitting 710 a directional transmission using the first transmit beam, which is selected from a plurality of transmit beams. Method 700 includes determining 715 whether the directional transmission has been successfully received by the receiver. Method 700 includes updating 720 a first contention window size (“CWS”) specific to the first transmit beam, wherein a separate CWS is maintained for each transmit beam that initiates the first channel occupancy.

[0220] In one embodiment, updating the first CWS (Current State Width) 720 includes adjusting the first CWS to the next allowed value in response to determining that the directional transmission was not successfully received by the receiver. In another embodiment, updating the first CWS 720 includes setting the first CWS to a minimum value in response to determining that the directional transmission was successfully received by the receiver. Method 700 includes performing the subsequent LBT (Low-Level Transmission) procedure 725 using the updated first CWS before a subsequent directional transmission using the first transmit beam. Method 700 ends.

[0221] Figure 8 One embodiment of a method 800 for adjusting the size of a contention window according to embodiments of the present disclosure is depicted. In various embodiments, method 800 is performed by a user equipment device in a mobile communication network, such as remote unit 105, UE 205, and / or user equipment device 500 as described above. In some embodiments, method 800 is performed by a processor, such as a microcontroller, microprocessor, CPU, GPU, auxiliary processing unit, FPGA, etc.

[0222] Method 800 begins and performs an 805 LBT procedure on the set of transmit beams. As described above, the LBT procedure can be performed sequentially (i.e., in TDM mode) or in parallel. Method 800 includes performing an 810 PUCCH transmission on at least one beam in the set of transmit beams in response to a successful LBT for the transmit beam. Method 800 includes determining whether the 815 PUCCH transmission was successfully received by the RAN node.

[0223] Method 800 includes updating 820 the CWS corresponding to each beam used in the PUCCH transmission, wherein a separate CWS is maintained for each transmission beam. In one embodiment, each CWS is adjusted to the next allowed value (i.e., a CWS value is selected from a predefined set of values) in response to determining that the PUCCH transmission has not been successfully received by the RAN node. In another embodiment, each CWS is set to a minimum value (i.e., "CWmin") in response to determining that the PUCCH transmission has been successfully received by the RAN node. Method 800 ends.

[0224] This document discloses a first apparatus for adjusting a contention window size according to embodiments of the present disclosure. The first apparatus may be implemented by radio communication equipment in a mobile communication network, such as the remote unit 105, base station unit 121, UE 205, gNB 210, user equipment device 500, and / or network device 600 described above. The first apparatus includes a processor and a transceiver comprising a plurality of transmit panels. In response to a successful Listen-After-Talk (“LBT”) procedure, the transceiver uses at least one transmit panel to initiate a first channel occupancy and uses the first transmit panel to transmit a directed transmission, the first transmit panel being selected from the plurality of transmit panels. The processor determines whether the directed transmission is successfully received by a receiver and updates a first contention window size (“CWS”) specific to the first transmit panel, wherein a separate CWS is maintained for each transmit panel that initiated the first channel occupancy.

[0225] In one embodiment, updating the first CWS includes adjusting the first CWS to the next allowed value in response to determining that the directed transmission was not successfully received by the receiver (e.g., where a CWS value is selected from a set of predefined values). In another embodiment, updating the first CWS includes setting the first CWS to a minimum value (i.e., "CWmin") in response to determining that the directed transmission was successfully received by the receiver. The processor uses the updated first CWS to perform subsequent LBT procedures before performing subsequent directed transmissions using the first transmit panel. Note that although the first apparatus is described in terms of using a "transmit panel" and updating the CWS for the first transmit panel, in other embodiments, the first method may involve a "transmit beam" and may update the CWS for the first transmit beam.

[0226] In some embodiments, determining whether a directed transmission has been successfully received by the receiver includes using a first receiving panel to receive a Hybrid Automatic Repeat Request (“HARQ”) feedback corresponding to the directed transmission. In such embodiments, updating the first CWS depends on the HARQ feedback (e.g., ACK or NACK) generated for the first transmitting panel, wherein updating the CWS does not depend on the first receiving panel (i.e., it does not depend on the beam of the HARQ-ACK feedback carrying the data channel).

[0227] In some embodiments, directed transmission includes data transmission on a sidelink channel (e.g., PSSCH) in which a common HARQ-NACK feedback resource (i.e., PSFCH option 1) is configured. In such embodiments, the absence of negative HARQ feedback corresponding to the directed transmission (i.e., the absence of HARQ-NACK) indicates that the directed transmission has been successfully received by the receiver, such that updating the first CWS includes setting the first CWS to a minimum value in response to detecting the absence of HARQ-NACK feedback.

[0228] In some embodiments, the received HARQ feedback includes multiple feedback responses. In such embodiments, determining that the directed transmission was successfully received by the receiver in response to at least one of the multiple feedback responses being an affirmative response (i.e., ACK) makes updating the first CWS include setting the first CWS to a minimum value in response to at least one of the multiple feedback responses being an affirmative response.

[0229] In some embodiments, determining whether a directed transmission was successfully received by the receiver includes receiving a New Data Indicator (“NDI”) and determining whether the directed transmission was successful based on the NDI. In some embodiments, the NDI is converted to indicate that the directed transmission was successfully received by the receiver compared to a previous state, while the NDI is not converted to indicate that the directed transmission was not successfully received by the receiver compared to a previous state.

[0230] In some embodiments, determining whether a directed transmission was successfully received by the receiver includes detecting the expiration of a retransmission timer (i.e., a CG retransmission timer) used for the HARQ process corresponding to the directed transmission. In such embodiments, the expiration of the retransmission timer indicates that the directed transmission was not successfully received by the receiver.

[0231] In some embodiments, directed transmissions are associated with a first channel access priority class (“CAPC”), wherein the CWS value is based on the first CAPC. In such embodiments, the processor maintains a separate set of CWS values ​​for each of a plurality of CAPCs, including the first CAPC. In some embodiments, directed transmissions include uplink control information (“UCI”) transmitted on a data channel (i.e., PUSCH). In such embodiments, updating the first CWS depends on HARQ feedback generated for the data channel.

[0232] In some embodiments, adjusting the first CWS to the next allowed value includes increasing the first CWS according to the function: min(CW×2+1,CWmax), where the value 'CW' represents the current value of the first CWS, the value 'CWmax' represents the maximum value of the first CWS, and the function selects the minimum of the two candidate values. In another embodiment, the minimum value of the first CWS (i.e., 'CWmin') and the maximum value of the first CWS (i.e., 'CWmax') are based on the CAPC of the directed transmission.

[0233] In some embodiments, the processor tracks the number of times the first CWS is used when it is at its maximum value for the first transmit panel. In such embodiments, if the first CWS is the maximum value, the next allowed value is the maximum value until a threshold usage number is reached, wherein the first CWS is reset to the minimum value for the first transmit panel in response to reaching the threshold usage number. In some embodiments, updating the first CWS includes maintaining the current value of the first CWS.

[0234] In some embodiments, while directional transmission using the first transmitting panel is in progress, the processor executes a second LBT process to initiate a second channel occupation for the second transmitting panel, different from the first channel occupation. In such embodiments, the transmitter may use the transmitting panel with the lowest CWS to transmit a data transmission block (“TB”) at the start of the LBT (i.e., CCA) process, the transmitting panel being selected from the first and second transmitting panels.

[0235] In some embodiments, the processor stops ongoing directional transmission using the first transmitter panel in response to initiating a second LBT process. In other embodiments, the second CWS corresponding to the second transmitter panel is adjusted independently of the first CWS based on the CAPC value used during the execution of the LBT process.

[0236] This document discloses a first method for adjusting the contention window size according to embodiments of the present disclosure. The first method can be performed by radio communication devices in a mobile communication network as described above, such as remote unit 105, base station unit 121, UE 205, gNB 210, user equipment device 500, and / or network device 600. The first method includes initiating a first channel occupancy using at least one transmit beam in response to a successful LBT procedure and transmitting a directional transmission using the first transmit beam, which is selected from a plurality of transmit beams. The first method includes determining at the communication device whether the directional transmission has been successfully received by a receiver and updating a first CWS specific to the first transmit beam, wherein a separate CWS is maintained for each transmit beam initiating the first channel occupancy. Note that while the first method is described using the phrase "transmit beam selected from a plurality of transmit beams," in other embodiments, the first method may involve "transmit panels selected from a plurality of transmit panels."

[0237] In one embodiment, updating the first CWS includes adjusting the first CWS to the next allowed value (e.g., where the CWS value is selected from a predefined set of values) in response to determining that the directed transmission was not successfully received by the receiver. In another embodiment, updating the first CWS includes setting the first CWS to a minimum value in response to determining that the directed transmission was successfully received by the receiver. The first method includes performing a subsequent LBT procedure using the updated first CWS prior to a subsequent directed transmission using the first transmit beam.

[0238] In some embodiments, determining whether a directed transmission has been successfully received by the receiver includes using a first receive beam to receive HARQ feedback corresponding to the directed transmission. In such embodiments, updating the first CWS depends on the HARQ feedback (i.e., ACK or NACK) generated for the first transmit beam, wherein updating the CWS does not depend on the first receive beam (i.e., not on the beam carrying the HARQ-ACK feedback of the data channel).

[0239] In some embodiments, the directed transmission includes data transmission on a sidelink channel (e.g., PSSCH) configured with common HARQ-NACK feedback resources (i.e., PSFCH option 1). In such embodiments, the absence of negative HARQ feedback corresponding to the directed transmission (i.e., the absence of HARQ-NACK) indicates that the directed transmission has been successfully received by the receiver, such that updating the first CWS includes setting the first CWS to a minimum value in response to detecting the absence of HARQ-NACK feedback. In some embodiments, the received HARQ feedback includes multiple feedback responses. In such embodiments, it is determined that the directed transmission has been successfully received by the receiver in response to at least one of the multiple feedback responses being a positive response (i.e., ACK), such that updating the first CWS includes setting the first CWS to a minimum value in response to at least one of the multiple feedback responses being a positive response.

[0240] In some embodiments, determining whether a directed transmission was successfully received by the receiver includes receiving an NDI and determining whether the directed transmission was successful based on the NDI. In some embodiments, the NDI is converted to indicate that the directed transmission was successfully received by the receiver compared to a previous state, while the NDI is not converted to indicate that the directed transmission was not successfully received by the receiver compared to a previous state.

[0241] In some embodiments, determining whether a directed transmission has been successfully received by the receiver includes detecting the expiration of a retransmission timer (i.e., a CG retransmission timer) for the HARQ process corresponding to the directed transmission. In such embodiments, the expiration of the retransmission timer indicates that the directed transmission has not been successfully received by the receiver.

[0242] In some embodiments, a directed transmission is associated with a first CAPC, wherein the CWS value is based on the first CAPC. In such embodiments, the first method further includes maintaining a separate set of CWS values ​​for each of a plurality of CAPCs, the plurality of CAPCs including the first CAPC. In some embodiments, the directed transmission includes a UCI transmitted on a data channel (i.e., PUSCH). In such embodiments, updating the first CWS depends on a HARQ feedback generated for the data channel.

[0243] In some embodiments, adjusting the first CWS to the next allowed value includes increasing the first CWS according to the following formula: min(CW×2+1, CWmax), where the value "CW" represents the current value CWS of the first CWS, the value "CWmax" represents the maximum value of the first CWS, and the function selects the minimum of the two candidate values. In a further embodiment, the minimum value of the first CWS (i.e., "CWmin") and the maximum value of the first CWS (i.e., "CWmax") are based on CAPC for directed transmission.

[0244] In some embodiments, the first method includes tracking the number of times a first CWS is used when it is at its maximum value for a first transmit panel, wherein if the first CWS is at its maximum value, the next allowed value is the maximum value until a threshold usage number is reached, wherein in response to reaching the threshold usage number, the first CWS is reset to its minimum value for the first transmit beam. In some embodiments, updating the first CWS includes maintaining the current value of the first CWS.

[0245] In some embodiments, the first method includes performing a second LBT procedure to initiate a second channel occupation for a second transmit beam, different from the first channel occupation via the first transmit beam, while directional transmission using the first transmit beam is in progress. In such embodiments, the first method may further include transmitting data TB using a transmit beam with the lowest CWS at the start of the LBT procedure, the transmit beam being selected from the first and second transmit beams.

[0246] In some embodiments, the first method further includes stopping the ongoing directional transmission using the first transmit beam in response to the commencement of a second LBT process. In a further embodiment, a second CWS corresponding to the second transmit beam is adjusted independently of the first CWS based on the CAPC value used during the execution of the LBT process.

[0247] This document discloses a second means for adjusting the size of a contention window according to embodiments of the present disclosure. The second means may be implemented by a user equipment device in a mobile communication network, such as remote unit 105, UE 205, and / or user equipment device 500 as described above. The second means includes a processor and a transceiver comprising a plurality of transmit panels. The processor performs an LBT process on the set of transmit panels. As described above, the LBT process may be performed sequentially (i.e., in a TDM manner) or in parallel.

[0248] In response to a successful LBT on a transmit panel, the processor performs a Physical Uplink Control Channel (“PUCCH”) transmission on at least one panel in the set of transmit panels and determines whether the PUCCH transmission was successfully received by a Radio Access Network (“RAN”) node. The processor updates the CWS corresponding to each panel used in the PUCCH transmission, wherein a separate CWS is maintained for each transmit panel. In one embodiment, the processor updates each CWS by adjusting it to the next allowed value (e.g., where a CWS value is selected from a set of predefined values) in response to determining that the PUCCH transmission was not successfully received by the RAN node. In another embodiment, the processor updates each CWS by setting it to a minimum value (i.e., “CWmin”) in response to determining that the PUCCH transmission was successfully received by the RAN node. As described above, while the second apparatus is described in terms of performing LBT on multiple transmit panels and updating the CWS for each panel used in the PUCCH transmission, in other embodiments, the second apparatus may perform LBT on multiple transmit beams and update the CWS for each beam used in the PUCCH transmission.

[0249] In some embodiments, the processor receives (i.e., via a transceiver) multiple NDIs for multiple HARQ processes corresponding to a PUCCH transmission, and determines a HARQ feedback error rate based on the HARQ feedback reported in the PUCCH transmission and the multiple NDIs. In such an embodiment, a PUCCH transmission is determined to have been successfully received by the RAN node in response to the HARQ feedback error rate being below a threshold, such that if the HARQ feedback error rate is below the threshold, the CWS of each panel used in the PUCCH transmission is set to a minimum value (i.e., "CWmin").

[0250] In some embodiments, the processor receives a set of downlink assignment index (“DAI”) values ​​corresponding to the PUCCH transmission. In such embodiments, determining whether the PUCCH transmission was successfully received by the RAN node includes comparing the set of DAI values ​​with HARQ feedback reported in the PUCCH transmission. In some embodiments, determining whether the PUCCH transmission was successfully received by the RAN node includes receiving a CWS adjustment indicator from the RAN node. In such embodiments, updating the CWS includes adjusting the CWS value according to the adjustment indicator.

[0251] In some embodiments, adjusting each CWS to the next allowed value includes incrementing CWS according to the function: min(CW×2+1, CWmax), where the value "CW" represents the current value of CWS, the value "CWmax" represents the maximum value of CWS, and the function selects the minimum of two candidate values. In a further embodiment, the minimum value (i.e., "CWmin") and maximum value (i.e., "CWmax") of each CWS are based on the CAPC transmitted via PUCCH. In some embodiments, updating each CWS includes maintaining the current value of the CWS.

[0252] This document discloses a second method for adjusting the contention window size according to embodiments of the present disclosure. The second method can be performed by a user equipment device in a mobile communication network, such as remote unit 105, UE 205, and / or user equipment device 500 as described above. The second method includes performing an LBT procedure on a set of transmit beams. As described above, the LBT procedure can be performed sequentially (i.e., in a TDM manner) or in parallel.

[0253] The second method includes performing a PUCCH transmission on at least one beam in the set of transmit beams in response to a successful LBT for the transmit beam, and determining at the UE whether the PUCCH transmission was successfully received by the RAN node. The second method includes updating the CWS corresponding to each beam used in the PUCCH transmission, wherein a separate CWS is maintained for each transmit beam. In one embodiment, in response to determining that the PUCCH transmission was not successfully received by the RAN node, each CWS is adjusted to the next allowed value (e.g., where a CWS value is selected from a set of predefined values). In another embodiment, in response to determining that the PUCCH transmission was successfully received by the RAN node, each CWS is set to a minimum value (i.e., "CWmin"). As described above, while the second method is described in terms of performing LBT on multiple transmit panels and updating the CWS for each panel used in the PUCCH transmission, in other embodiments, the second method may perform LBT on multiple transmit panels and update the CWS for each panel used in the PUCCH transmission.

[0254] In some embodiments, the second method includes receiving multiple NDIs for multiple HARQ processes corresponding to a PUCCH transmission, and determining a HARQ feedback error rate based on HARQ feedback reported in the PUCCH transmission and the multiple NDIs. In such an embodiment, in response to determining that the PUCCH transmission has been successfully received by the RAN node if the HARQ feedback error rate is below a threshold, the CWS of each panel used in the PUCCH transmission is set to a minimum value (i.e., "CWmin") if the HARQ feedback error rate is below the threshold.

[0255] In some embodiments, the second method includes receiving a set of DAI values ​​corresponding to a PUCCH transmission. In such embodiments, determining whether a PUCCH transmission was successfully received by the RAN node includes comparing the set of DAI values ​​with HARQ feedback reported in the PUCCH transmission. In some embodiments, determining whether a PUCCH transmission was successfully received by the RAN node includes receiving a CWS adjustment indicator from the RAN node. In such embodiments, updating the CWS includes adjusting the CWS value according to the adjustment indicator.

[0256] In some embodiments, adjusting each CWS to the next allowed value includes incrementing CWS according to the function: min(CW×2+1, CWmax), where the value "CW" represents the current value of CWS, the value "CWmax" represents the maximum value of CWS, and the function selects the minimum of two candidate values. In a further embodiment, the minimum value (i.e., "CWmin") and maximum value (i.e., "CWmax") of each CWS are based on the CAPC transmitted via PUCCH. In some embodiments, updating each CWS includes maintaining the current value of the CWS.

[0257] The embodiments may be practiced in other specific forms. The described embodiments are to be considered in all respects as illustrative rather than restrictive. Therefore, the scope of the invention is indicated by the appended claims rather than by the foregoing description. All variations within the equivalent meaning and scope of the claims should be covered within their scope.

Claims

1. A method for using a communication device, the method comprising: In response to a successful Listen-Before-Speak ("LBT") process, at least one transmit beam is used to initiate the first channel occupation; A first transmit beam is used to transmit directional transmission, the first transmit beam being selected from a plurality of transmit beams; At the communication device, it is determined whether the directed transmission has been successfully received by the receiver. Update the first contention window size ("CWS") specific to the first transmitted beam, wherein updating the first CWS includes: In response to determining that the directed transmission was not successfully received by the receiver, the first CWS is adjusted to the next allowed value, and In response to determining that the directional transmission has been successfully received by the receiver, the first CWS is set to a minimum value, wherein a separate CWS is maintained for each transmit beam that initiates the occupation of the first channel; and Before subsequent directional transmission using the first transmit beam, the updated first CWS is used to perform the subsequent LBT process. Determining whether the directional transmission was successfully received by the receiver includes: using a first receive beam to receive Hybrid Automatic Repeat Request ("HARQ") feedback corresponding to the directional transmission, wherein updating the first CWS depends on the HARQ feedback generated for the first transmit beam, and wherein updating the CWS does not depend on the first receive beam.

2. The method according to claim 1, wherein, The directed transmission includes data transmission on a sidelink channel in which a common HARQ-NACK feedback resource is configured, wherein the absence of negative HARQ feedback corresponding to the directed transmission indicates that the directed transmission has been successfully received by the receiver, wherein updating the first CWS includes: setting the first CWS to the minimum value in response to detecting the absence of the HARQ-NACK feedback.

3. The method according to claim 1, wherein, The received HARQ feedback includes multiple feedback responses, wherein the directed transmission is successfully received by the receiver in response to at least one of the multiple feedback responses being an affirmative response, wherein updating the first CWS includes setting the first CWS to the minimum value in response to at least one of the multiple feedback responses being an affirmative response.

4. The method according to claim 1, wherein, Determining whether the directed transmission was successfully received by the receiver includes receiving a New Data Indicator ("NDI"), wherein the NDI is converted to indicate that the directed transmission was successfully received by the receiver compared to a previous state, and wherein the NDI is not converted to indicate that the directed transmission was not successfully received by the receiver compared to a previous state.

5. The method according to claim 1, wherein, Determining whether the directed transmission was successfully received by the receiver includes: detecting the expiration of a retransmission timer for the Hybrid Automatic Repeat Request ("HARQ") process corresponding to the directed transmission, wherein the expiration of the retransmission timer indicates that the directed transmission was not successfully received by the receiver.

6. The method according to claim 1, wherein, The directed transmission is associated with a first channel access priority class ("CAPC"), wherein the CWS value is based on the first CAPC, and the method further includes maintaining a separate set of CWS values ​​for each of a plurality of CAPCs, the plurality of CAPCs including the first CAPC.

7. The method according to claim 1, wherein, The directed transmission includes uplink control information transmitted on the data channel, and wherein updating the first CWS depends on the Hybrid Automatic Repeat Request ("HARQ") feedback generated for the data channel.

8. The method according to claim 1, wherein, The directed transmission includes uplink control information sent on the PUSCH.

9. The method according to claim 1, wherein, Adjusting the first CWS to the next allowed value includes: increasing the first CWS according to the formula min(CW×2+1, CWmax), where the value "CW" represents the current value of the first CWS and the value "CWmax" represents the maximum value of the first CWS.

10. The method of claim 9, further comprising tracking the number of times the first CWS is used when the first transmit beam is at its maximum value, wherein, If the first CWS is currently at the maximum value, then the next allowed value is the maximum value until a threshold usage number is reached, wherein, in response to reaching the threshold usage number, the first CWS is reset to the minimum value for the first transmit beam, wherein the minimum value for the first CWS and the maximum value for the first CWS are based on the channel access priority class of the directed transmission.

11. The method according to claim 1, wherein, Updating the first CWS includes maintaining the current value of the first CWS.

12. The method of claim 1, further comprising: A second LBT procedure is performed to initiate a second channel occupation for the second transmit beam that is different from the first channel occupation while directional transmission using the first transmit beam is in progress, wherein the second CWS corresponding to the second transmit beam is adjusted independently of the first CWS based on the channel access priority class value used when performing the LBT procedure.

13. The method of claim 12, further comprising transmitting a data transmission block ("TB") using a transmit beam having the lowest CWS at the start of the LBT process, the transmit beam being selected from the first transmit beam and the second transmit beam.

14. The method of claim 12, further comprising stopping the ongoing directional transmission using the first transmit beam in response to initiating the second LBT process.

15. An apparatus for wireless communication, the apparatus comprising: A transceiver comprising a plurality of transmitting panels, wherein the transceiver: In response to a successful Listen-Before-Speak ("LBT") process, at least one transmit panel is used to initiate the first channel occupancy; and A directional transmission is transmitted using a first transmitting panel, the first transmitting panel being selected from the plurality of transmitting panels; and Processor, the processor: Determine whether the directed transmission was successfully received by the receiver; Update the first contention window size ("CWS") specific to the first transmit panel, wherein updating the first CWS includes: In response to determining that the directed transmission was not successfully received by the receiver, the first CWS is adjusted to the next allowed value, and In response to determining that the directed transmission has been successfully received by the receiver, the first CWS is set to a minimum value, wherein a separate CWS is maintained for each transmitting panel that initiated the first channel occupancy; and Before subsequent directional transmissions using the first transmitting panel, the updated first CWS is used to perform the subsequent LBT process. To determine whether the directional transmission has been successfully received by the receiver, the processor uses a first receive beam to receive Hybrid Automatic Repeat Request ("HARQ") feedback corresponding to the directional transmission. Updating the first CWS depends on the HARQ feedback generated for the first transmit beam, and updating the CWS does not depend on the first receive beam.

16. A method of a user equipment apparatus ("UE"), the method comprising: The Listen-Before-Speak (LBT) process is performed on the set of transmitted beams. In response to a successful LBT for a transmit beam, a Physical Uplink Control Channel ("PUCCH") transmission is performed on at least one beam in the set of transmit beams, wherein the PUCCH transmission is a directional transmission; At the UE, it is determined whether the PUCCH transmission was successfully received by the radio access network ("RAN") node; and Update the contention window size ("CWS") corresponding to each of the at least one beam, wherein updating each CWS includes: In response to determining that the PUCCH transmission was not successfully received by the RAN node, the CWS is adjusted to the next allowed value, and In response to determining that the PUCCH transmission has been successfully received by the RAN node, the CWS is set to a minimum value, wherein a separate CWS is maintained for each transmit beam. Determining whether the PUCCH transmission was successfully received by the RAN node includes: using a receive beam to receive Hybrid Automatic Repeat Request ("HARQ") feedback corresponding to the PUCCH transmission, wherein updating the CWS depends on the HARQ feedback generated for the transmit beam, and updating the CWS does not depend on the receive beam.

17. The method of claim 16, further comprising: Receive multiple New Data Indicators (NDIs) for multiple Hybrid Automatic Repeat Request ("HARQ") processes corresponding to the PUCCH transmission. as well as The HARQ feedback error rate is determined based on the HARQ feedback reported during the PUCCH transmission and the multiple NDIs. Specifically, in response to the HARQ feedback error rate being lower than a threshold, it is determined that the PUCCH transmission has been successfully received by the RAN node.

18. The method of claim 16, further comprising: Receive a set of downlink assignment index ("DAI") values ​​corresponding to the PUCCH transmission. Determining whether the PUCCH transmission was successfully received by the RAN node includes comparing the set of DAI values ​​with the HARQ feedback reported in the PUCCH transmission.

19. The method of claim 16, wherein, Determining whether the PUCCH transmission was successfully received by the RAN node includes: receiving a CWS adjustment indicator from the RAN node, wherein updating the CWS includes adjusting the CWS value according to the adjustment indicator.

20. A user equipment ("UE") apparatus, comprising: A transceiver, the transceiver comprising a plurality of transmitting panels; as well as Processor, the processor: The Listen-Before-Speak (LBT) process is performed on the collection of transmitter panels; In response to a successful LBT for a transmitting panel, a Physical Uplink Control Channel ("PUCCH") transmission is performed on at least one panel in the set of transmitting panels, wherein the PUCCH transmission is a directed transmission; Determine whether the PUCCH transmission was successfully received by the Radio Access Network ("RAN") node; and Update the contention window size ("CWS") corresponding to each of the at least one panel, wherein updating each CWS includes: In response to determining that the PUCCH transmission was not successfully received by the RAN node, the CWS is adjusted to the next allowed value, and In response to determining that the PUCCH transmission has been successfully received by the RAN node, the CWS is set to a minimum value, wherein a separate CWS is maintained for each transmit panel. To determine whether the PUCCH transmission has been successfully received by the RAN node, the processor uses a receive beam to receive Hybrid Automatic Repeat Request ("HARQ") feedback corresponding to the PUCCH transmission. The update of the CWS depends on the HARQ feedback generated for the transmit beam, and the update of the CWS does not depend on the receive beam.

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