WO2022204929A1

WO2022204929A1 - Techniques for priority-based channel access for channel occupancy times

Info

Publication number: WO2022204929A1
Application number: PCT/CN2021/083895
Authority: WO
Inventors: Shaozhen GUO; Jing Sun; Changlong Xu; Xiaoxia Zhang; Aleksandar Damnjanovic; Rajat Prakash
Original assignee: Qualcomm Incorporated
Priority date: 2021-03-30
Filing date: 2021-03-30
Publication date: 2022-10-06

Abstract

Methods, systems, and devices for wireless communications are described. A first base station may determine a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum including a set of fixed frame periods (FFPs). The first base station may select at least one of a position or an energy detection threshold associated with a first clear channel assessment (CCA) resource of a first FFP of the set of fixed frame periods in accordance with the first channel access priority. The base station may then perform a channel access contention procedure for a channel occupancy time (COT) within the first FFP and within the first CCA resource using the selected position or energy detection threshold, and may communicate with a user equipment (UE) within the COT in accordance with a result of the channel access contention procedure.

Description

TECHNIQUES FOR PRIORITY-BASED CHANNEL ACCESS FOR CHANNEL OCCUPANCY TIMES

FIELD OF TECHNOLOGY

The following relates to wireless communications, including techniques for priority-based channel access for channel occupancy times (COTs) .

BACKGROUND

Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power) . Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may be referred to as New Radio (NR) systems. These systems may employ technologies such as code division multiple access (CDMA) , time division multiple access (TDMA) , frequency division multiple access (FDMA) , orthogonal FDMA (OFDMA) , or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) . A wireless multiple-access communications system may include one or more base stations or one or more network access nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE) .

Some wireless communications systems may support communications over unlicensed spectrum (e.g., “contention-based” spectrum) . In the context of unlicensed spectrum, wireless devices (e.g., base stations) may perform listen-before-talk (LBT) procedures and/or channel access contention procedures in order to “win” access of a channel occupancy time (COT) within a fixed frame period (FFP) of the unlicensed spectrum.

SUMMARY

The described techniques relate to improved methods, systems, devices, and apparatuses that support techniques for priority-based channel access for channel occupancy times (COTs) . Generally, the aspects of the present disclosure provide techniques for priority-based channel access techniques for COTs associated with unlicensed spectrum. More specifically, aspects of the present disclosure provide techniques which enable base stations to select clear channel assessment (CCA) resources associated with floating COTs based on relative priorities between the respective base stations. For example, a base station may be configured to determine its channel access priority, and may select a position and/or an energy detection threshold associated with a CCA resource of a fixed frame period (FFP) based on its determined channel access priority. The base station may subsequently perform a channel access contention procedure for a COT within the FFP based on the selected position/energy detection threshold of the CCA resource, and may communicate with user equipments (UEs) during the COT based on a result of the channel access contention procedure (e.g., based on winning use of the COT via the channel access contention procedure) .

A method for wireless communication at a first base station is described. The method may include determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs, selecting at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain, performing a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold, and communicating with one or more user equipments (UEs) within the COT in accordance with a result of the channel access contention procedure.

An apparatus for wireless communication at a first base station is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to determine a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs, select at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain, perform a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold, and communicate with one or more user equipments (UEs) within the COT in accordance with a result of the channel access contention procedure.

Another apparatus for wireless communication at a first base station is described. The apparatus may include means for determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs, means for selecting at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain, means for performing a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold, and means for communicating with one or more user equipments (UEs) within the COT in accordance with a result of the channel access contention procedure.

A non-transitory computer-readable medium storing code for wireless communication at a first base station is described. The code may include instructions executable by a processor to determine a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs, select at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain, perform a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold, and communicate with one or more user equipments (UEs) within the COT in accordance with a result of the channel access contention procedure.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting at least one of the position or the energy detection threshold may include operations, features, means, or instructions for selecting at least one of the position or the energy detection threshold associated with the first CCA resource based on a comparison of the first channel access priority and a second channel access priority associated with a second base station.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting at least one of the position or the energy detection threshold may include operations, features, means, or instructions for selecting the position of the first CCA resource, where the position of the first CCA resource may be earlier in the time domain relative to an additional position of an additional CCA resource associated with an additional base station based on the first channel access priority being greater than an additional channel access priority associated with the additional base station, or where the position of the first CCA resource may be later in the time domain relative to the additional position of the additional CCA resource associated with the additional base station based on the first channel access priority being less than the additional channel access priority associated with the additional base station.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting at least one of the position or the energy detection threshold may include operations, features, means, or instructions for determining a set of position candidates associated with a set of multiple CCA resources within the set of multiple FFPs, the first CCA resource included within the set of multiple CCA resources, where each position candidate of the set of position candidates defines a starting point of the set of multiple CCA resources within the set of multiple FFPs in the time domain and selecting the position of the first CCA resource from the set of position candidates based on the first channel access priority.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the selected position may be associated with each CCA resource of the set of multiple CCA resources.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting at least one of the position or the energy detection threshold may include operations, features, means, or instructions for selecting the energy detection threshold of the first CCA resource, where the energy detection threshold of the first CCA resource may be greater than an additional energy detection threshold of an additional CCA resource associated with an additional base station based on the first channel access priority being greater than an additional channel access priority associated with the additional base station, or where the energy detection threshold of the first CCA resource may be less than the additional energy detection threshold of the additional CCA resource associated with the additional base station based on the first channel access priority being less than the additional channel access priority associated with the additional base station.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting at least one of the position or the energy detection threshold may include operations, features, means, or instructions for determining a set of energy detection threshold candidates associated with a set of multiple CCA resources within the set of multiple FFPs, the first CCA resource included within the set of multiple CCA resources and selecting the energy detection threshold of the first CCA resource from the set of energy detection threshold candidates based on the first channel access priority.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, selecting at least one of the position or the energy detection threshold may include operations, features, means, or instructions for determining a set of position candidates associated with the set of multiple CCA resources within the set of multiple FFPs, the first CCA resource included within the set of multiple CCA resources and selecting the position of the first CCA resource from the set of position candidates based on the first channel access priority.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for determining a communication priority associated with a communication scheduled to be performed by the first base station and determining the first channel access priority based on the communication priority.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the communication may be scheduled to be performed within the first FFP and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for determining an additional communication priority associated with an additional communication scheduled to be performed by the first base station within an additional FFP and determining an additional channel access priority associated with the first base station and associated with the additional FFP based on the additional communication priority.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for selecting at least one of an additional position or an additional energy detection threshold associated with an additional CCA resource of the additional FFP of the set of multiple FFPs based on the additional channel access priority, performing an additional channel access contention procedure for an additional COT within the additional FFP and within the additional CCA resource and based on the selecting, and communicating with one or more UEs within the additional COT in accordance with a result of the additional channel access contention procedure.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting a receiver protection signal during an additional CCA resource associated with an additional base station based on performing the channel access contention procedure, where communicating with the one or more UEs may be based on transmitting the receiver protection signal.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting, to a UE of the one or more UEs, control signaling including an indication of a resource associated with a receiver protection signal, where the resource at least partially overlaps with an additional CCA resource associated with an additional base station in the time domain, where communicating with the one or more UEs may be based on transmitting the control signaling.

A method for wireless communication at a UE is described. The method may include receiving control signaling indicating a CCA resource associated with a second base station, the CCA resource positioned within a FFP of a set of multiple FFPs associated with unlicensed spectrum, receiving, from a first base station different from the second base station, a downlink message within a COT of the FFP, where the CCA resource is positioned within the COT in the time domain, and transmitting a receiver protection signal during the CCA resource associated with the second base station based on receiving the downlink message.

An apparatus for wireless communication at a UE is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive control signaling indicating a CCA resource associated with a second base station, the CCA resource positioned within a FFP of a set of multiple FFPs associated with unlicensed spectrum, receive, from a first base station different from the second base station, a downlink message within a COT of the FFP, where the CCA resource is positioned within the COT in the time domain, and transmit a receiver protection signal during the CCA resource associated with the second base station based on receiving the downlink message.

Another apparatus for wireless communication at a UE is described. The apparatus may include means for receiving control signaling indicating a CCA resource associated with a second base station, the CCA resource positioned within a FFP of a set of multiple FFPs associated with unlicensed spectrum, means for receiving, from a first base station different from the second base station, a downlink message within a COT of the FFP, where the CCA resource is positioned within the COT in the time domain, and means for transmitting a receiver protection signal during the CCA resource associated with the second base station based on receiving the downlink message.

A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to receive control signaling indicating a CCA resource associated with a second base station, the CCA resource positioned within a FFP of a set of multiple FFPs associated with unlicensed spectrum, receive, from a first base station different from the second base station, a downlink message within a COT of the FFP, where the CCA resource is positioned within the COT in the time domain, and transmit a receiver protection signal during the CCA resource associated with the second base station based on receiving the downlink message.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the control signaling includes a radio resource control message and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for receiving, via the radio resource control message, the downlink control information message, or both, an indication of a set of multiple CCA resources associated with the UE, where the set of multiple CCA resources include the CCA resource, and where each CCA resource of the set of multiple CCA resources corresponds to a FFP of the set of multiple FFPs.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a wireless communications system that supports techniques for priority-based channel access for channel occupancy times (COTs) in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIG. 3 illustrates an example of a resource configuration that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIG. 4 illustrates an example of a resource configuration that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIG. 5 illustrates an example of a resource configuration that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIG. 6 illustrates an example of a process flow that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIGs. 7 and 8 show block diagrams of devices that support techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIG. 9 shows a block diagram of a communications manager that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIG. 10 shows a diagram of a system including a device that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIGs. 11 and 12 show block diagrams of devices that support techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIG. 13 shows a block diagram of a communications manager that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIG. 14 shows a diagram of a system including a device that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

FIGs. 15 through 18 show flowcharts illustrating methods that support techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Some wireless communications systems may support communications over unlicensed spectrum (e.g., “contention-based” spectrum) . In the context of unlicensed spectrum, wireless devices (e.g., base stations) may perform listen-before-talk (LBT) procedures and/or channel access contention procedures in order to “win” access of a channel occupancy time (COT) within a fixed frame period (FFP) of the unlicensed spectrum. For example, a base station may perform a channel access contention procedure within a clear channel assessment (CCA) resource (e.g., CCA procedure) in order to compete for use of a COT, and may subsequently perform communications within the COT based on winning access to the COT via the channel access contention procedure.

Some wireless communications systems may be configured with “fixed COTs, ” in which CCA resources used to compete for the use of the fixed COTs are located at the same position within each FFP. In such cases, all wireless devices (e.g., base stations) may perform channel access contention procedures at the same time (e.g., within the same CCA resources) , and may have an equal probability of gaining access to the COT. However, such equal access may be ill-suited in cases where base stations exhibit varying priorities. Some other wireless communications systems may be configured with “floating COTs, ” in which CCA resources used to compete for the use of the floating COTs are located at varying positions from one FFP to another. Floating COTs may enable different wireless devices to compete for use of the COT at different times, and may enable some wireless devices to have a higher probability of gaining access to the respective COTs. However, current wireless communications systems do not support configurations or other rules which enable base stations to select CCA resources and compete for floating COTs based on relative priorities between the base stations.

Accordingly, techniques described herein are directed to priority-based channel access techniques for COTs associated with unlicensed spectrum. More specifically, aspects of the present disclosure provide techniques which enable base stations to select CCA resources associated with floating COTs based on relative priorities between the respective base stations. For example, a base station may be configured to determine its channel access priority, and may select a position and/or an energy detection threshold associated with a CCA resource based on its determined channel access priority. The selected position may define a position of the CCA resource within the FFP in the time domain. The base station may subsequently perform a channel access contention procedure for a COT within the FFP based on the selected position/energy detection threshold of the CCA resource, and may communicate with UEs during the COT based on a result of the channel access contention procedure (e.g., based on winning use of the COT via the channel access contention procedure) .

In some aspects, a base station may be associated with a single channel access priority (e.g., “semi-static” priority) which remains constant from FFP to FFP. In other cases, the channel access priority of the base station may change based on a priority of communications scheduled to be performed by the base station (e.g., “dynamic” priority) . According to some implementations, higher-priority base stations may be configured to select earlier CCA resource positions as compared to lower-priority base stations, higher energy detection thresholds as compared to lower-priority base stations, or both. By selecting earlier CCA resource positions and/or higher energy detection thresholds, techniques described herein may increase the likelihood that the higher-priority base stations may successfully win the ability to communicate within floating COTs of unlicensed spectrum. In some aspects, upon winning use of a COT, a base station may transmit (or cause a UE to transmit) receiver protection signals within selected CCA resources of lower-priority base stations in order to prevent the lower-priority base stations from interfering with communications performed during the COT.

Aspects of the disclosure are initially described in the context of wireless communications systems. Additional aspects of the disclosure are described in the context of example resource configurations and an example process flow. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to techniques for priority-based channel access for COTs.

FIG. 1 illustrates an example of a wireless communications system 100 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The wireless communications system 100 may include one or more base stations 105, one or more UEs 115, and a core network 130. In some examples, the wireless communications system 100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. In some examples, the wireless communications system 100 may support enhanced broadband communications, ultra-reliable (e.g., mission critical) communications, low latency communications, communications with low-cost and low-complexity devices, or any combination thereof.

The base stations 105 may be dispersed throughout a geographic area to form the wireless communications system 100 and may be devices in different forms or having different capabilities. The base stations 105 and the UEs 115 may wirelessly communicate via one or more communication links 125. Each base station 105 may provide a coverage area 110 over which the UEs 115 and the base station 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area over which a base station 105 and a UE 115 may support the communication of signals according to one or more radio access technologies.

The UEs 115 may be dispersed throughout a coverage area 110 of the wireless communications system 100, and each UE 115 may be stationary, or mobile, or both at different times. The UEs 115 may be devices in different forms or having different capabilities. Some example UEs 115 are illustrated in FIG. 1. The UEs 115 described herein may be able to communicate with various types of devices, such as other UEs 115, the base stations 105, or network equipment (e.g., core network nodes, relay devices, integrated access and backhaul (IAB) nodes, or other network equipment) , as shown in FIG. 1.

The base stations 105 may communicate with the core network 130, or with one another, or both. For example, the base stations 105 may interface with the core network 130 through one or more backhaul links 120 (e.g., via an S1, N2, N3, or other interface) . The base stations 105 may communicate with one another over the backhaul links 120 (e.g., via an X2, Xn, or other interface) either directly (e.g., directly between base stations 105) , or indirectly (e.g., via core network 130) , or both. In some examples, the backhaul links 120 may be or include one or more wireless links.

One or more of the base stations 105 described herein may include or may be referred to by a person having ordinary skill in the art as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB) , a next-generation NodeB or a giga-NodeB (either of which may be referred to as a gNB) , a Home NodeB, a Home eNodeB, or other suitable terminology.

A UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable terminology, where the “device” may also be referred to as a unit, a station, a terminal, or a client, among other examples. A UE 115 may also include or may be referred to as a personal electronic device such as a cellular phone, a personal digital assistant (PDA) , a tablet computer, a laptop computer, or a personal computer. In some examples, a UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communications (MTC) device, among other examples, which may be implemented in various objects such as appliances, or vehicles, meters, among other examples.

The UEs 115 described herein may be able to communicate with various types of devices, such as other UEs 115 that may sometimes act as relays as well as the base stations 105 and the network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, among other examples, as shown in FIG. 1.

The UEs 115 and the base stations 105 may wirelessly communicate with one another via one or more communication links 125 over one or more carriers. The term “carrier” may refer to a set of radio frequency spectrum resources having a defined physical layer structure for supporting the communication links 125. For example, a carrier used for a communication link 125 may include a portion of a radio frequency spectrum band (e.g., a bandwidth part (BWP) ) that is operated according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-APro, NR) . Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information) , control signaling that coordinates operation for the carrier, user data, or other signaling. The wireless communications system 100 may support communication with a UE 115 using carrier aggregation or multi-carrier operation. A UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers according to a carrier aggregation configuration. Carrier aggregation may be used with both frequency division duplexing (FDD) and time division duplexing (TDD) component carriers.

In some examples (e.g., in a carrier aggregation configuration) , a carrier may also have acquisition signaling or control signaling that coordinates operations for other carriers. A carrier may be associated with a frequency channel (e.g., an evolved universal mobile telecommunication system terrestrial radio access (E-UTRA) absolute radio frequency channel number (EARFCN) ) and may be positioned according to a channel raster for discovery by the UEs 115. A carrier may be operated in a standalone mode where initial acquisition and connection may be conducted by the UEs 115 via the carrier, or the carrier may be operated in a non-standalone mode where a connection is anchored using a different carrier (e.g., of the same or a different radio access technology) .

The communication links 125 shown in the wireless communications system 100 may include uplink transmissions from a UE 115 to a base station 105, or downlink transmissions from a base station 105 to a UE 115. Carriers may carry downlink or uplink communications (e.g., in an FDD mode) or may be configured to carry downlink and uplink communications (e.g., in a TDD mode) .

A carrier may be associated with a particular bandwidth of the radio frequency spectrum, and in some examples the carrier bandwidth may be referred to as a “system bandwidth” of the carrier or the wireless communications system 100. For example, the carrier bandwidth may be one of a number of determined bandwidths for carriers of a particular radio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 megahertz (MHz) ) . Devices of the wireless communications system 100 (e.g., the base stations 105, the UEs 115, or both) may have hardware configurations that support communications over a particular carrier bandwidth or may be configurable to support communications over one of a set of carrier bandwidths. In some examples, the wireless communications system 100 may include base stations 105 or UEs 115 that support simultaneous communications via carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 may be configured for operating over portions (e.g., a sub-band, a BWP) or all of a carrier bandwidth.

Signal waveforms transmitted over a carrier may be made up of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM) ) . In a system employing MCM techniques, a resource element may consist of one symbol period (e.g., a duration of one modulation symbol) and one subcarrier, where the symbol period and subcarrier spacing are inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both) . Thus, the more resource elements that a UE 115 receives and the higher the order of the modulation scheme, the higher the data rate may be for the UE 115. A wireless communications resource may refer to a combination of a radio frequency spectrum resource, a time resource, and a spatial resource (e.g., spatial layers or beams) , and the use of multiple spatial layers may further increase the data rate or data integrity for communications with a UE 115.

One or more numerologies for a carrier may be supported, where a numerology may include a subcarrier spacing (Δf) and a cyclic prefix. A carrier may be divided into one or more BWPs having the same or different numerologies. In some examples, a UE 115 may be configured with multiple BWPs. In some examples, a single BWP for a carrier may be active at a given time and communications for the UE 115 may be restricted to one or more active BWPs.

The time intervals for the base stations 105 or the UEs 115 may be expressed in multiples of a basic time unit which may, for example, refer to a sampling period of T _s=1/ (Δf _max·N _f) seconds, where Δf _max may represent the maximum supported subcarrier spacing, and N _f may represent the maximum supported discrete Fourier transform (DFT) size. Time intervals of a communications resource may be organized according to radio frames each having a specified duration (e.g., 10 milliseconds (ms) ) . Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023) .

Each frame may include multiple consecutively numbered subframes or slots, and each subframe or slot may have the same duration. In some examples, a frame may be divided (e.g., in the time domain) into subframes, and each subframe may be further divided into a number of slots. Alternatively, each frame may include a variable number of slots, and the number of slots may depend on subcarrier spacing. Each slot may include a number of symbol periods (e.g., depending on the length of the cyclic prefix prepended to each symbol period) . In some wireless communications systems 100, a slot may further be divided into multiple mini-slots containing one or more symbols. Excluding the cyclic prefix, each symbol period may contain one or more (e.g., N _f) sampling periods. The duration of a symbol period may depend on the subcarrier spacing or frequency band of operation.

A subframe, a slot, a mini-slot, or a symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communications system 100 and may be referred to as a transmission time interval (TTI) . In some examples, the TTI duration (e.g., the number of symbol periods in a TTI) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communications system 100 may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs) ) .

Physical channels may be multiplexed on a carrier according to various techniques. A physical control channel and a physical data channel may be multiplexed on a downlink carrier, for example, using one or more of time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. A control region (e.g., a control resource set (CORESET) ) for a physical control channel may be defined by a number of symbol periods and may extend across the system bandwidth or a subset of the system bandwidth of the carrier. One or more control regions (e.g., CORESETs) may be configured for a set of the UEs 115. For example, one or more of the UEs 115 may monitor or search control regions for control information according to one or more search space sets, and each search space set may include one or multiple control channel candidates in one or more aggregation levels arranged in a cascaded manner. An aggregation level for a control channel candidate may refer to a number of control channel resources (e.g., control channel elements (CCEs) ) associated with encoded information for a control information format having a given payload size. Search space sets may include common search space sets configured for sending control information to multiple UEs 115 and UE-specific search space sets for sending control information to a specific UE 115.

In some examples, a base station 105 may be movable and therefore provide communication coverage for a moving geographic coverage area 110. In some examples, different geographic coverage areas 110 associated with different technologies may overlap, but the different geographic coverage areas 110 may be supported by the same base station 105. In other examples, the overlapping geographic coverage areas 110 associated with different technologies may be supported by different base stations 105. The wireless communications system 100 may include, for example, a heterogeneous network in which different types of the base stations 105 provide coverage for various geographic coverage areas 110 using the same or different radio access technologies.

The wireless communications system 100 may be configured to support ultra-reliable communications or low-latency communications, or various combinations thereof. For example, the wireless communications system 100 may be configured to support ultra-reliable low-latency communications (URLLC) or mission critical communications. The UEs 115 may be designed to support ultra-reliable, low-latency, or critical functions (e.g., mission critical functions) . Ultra-reliable communications may include private communication or group communication and may be supported by one or more mission critical services such as mission critical push-to-talk (MCPTT) , mission critical video (MCVideo) , or mission critical data (MCData) . Support for mission critical functions may include prioritization of services, and mission critical services may be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, mission critical, and ultra-reliable low-latency may be used interchangeably herein.

In some examples, a UE 115 may also be able to communicate directly with other UEs 115 over a device-to-device (D2D) communication link 135 (e.g., using a peer-to-peer (P2P) or D2D protocol) . One or more UEs 115 utilizing D2D communications may be within the geographic coverage area 110 of a base station 105. Other UEs 115 in such a group may be outside the geographic coverage area 110 of a base station 105 or be otherwise unable to receive transmissions from a base station 105. In some examples, groups of the UEs 115 communicating via D2D communications may utilize a one-to-many (1: M) system in which each UE 115 transmits to every other UE 115 in the group. In some examples, a base station 105 facilitates the scheduling of resources for D2D communications. In other cases, D2D communications are carried out between the UEs 115 without the involvement of a base station 105.

The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or 5G core (5GC) , which may include at least one control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management function (AMF) ) and at least one user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management for the UEs 115 served by the base stations 105 associated with the core network 130. User IP packets may be transferred through the user plane entity, which may provide IP address allocation as well as other functions. The user plane entity may be connected to IP services 150 for one or more network operators. The IP services 150 may include access to the Internet, Intranet (s) , an IP Multimedia Subsystem (IMS) , or a Packet-Switched Streaming Service.

Some of the network devices, such as a base station 105, may include subcomponents such as an access network entity 140, which may be an example of an access node controller (ANC) . Each access network entity 140 may communicate with the UEs 115 through one or more other access network transmission entities 145, which may be referred to as radio heads, smart radio heads, or transmission/reception points (TRPs) . Each access network transmission entity 145 may include one or more antenna panels. In some configurations, various functions of each access network entity 140 or base station 105 may be distributed across various network devices (e.g., radio heads and ANCs) or consolidated into a single network device (e.g., a base station 105) .

The wireless communications system 100 may operate using one or more frequency bands, typically in the range of 300 megahertz (MHz) to 300 gigahertz (GHz) . Generally, the region from 300 MHz to 3 GHz is known as the ultra-high frequency (UHF) region or decimeter band because the wavelengths range from approximately one decimeter to one meter in length. The UHF waves may be blocked or redirected by buildings and environmental features, but the waves may penetrate structures sufficiently for a macro cell to provide service to the UEs 115 located indoors. The transmission of UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to transmission using the smaller frequencies and longer waves of the high frequency (HF) or very high frequency (VHF) portion of the spectrum below 300 MHz.

The wireless communications system 100 may utilize both licensed and unlicensed radio frequency spectrum bands. For example, the wireless communications system 100 may employ License Assisted Access (LAA) , LTE-Unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed band such as the 5 GHz industrial, scientific, and medical (ISM) band. When operating in unlicensed radio frequency spectrum bands, devices such as the base stations 105 and the UEs 115 may employ carrier sensing for collision detection and avoidance. In some examples, operations in unlicensed bands may be based on a carrier aggregation configuration in conjunction with component carriers operating in a licensed band (e.g., LAA) . Operations in unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among other examples.

A base station 105 or a UE 115 may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of a base station 105 or a UE 115 may be located within one or more antenna arrays or antenna panels, which may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some examples, antennas or antenna arrays associated with a base station 105 may be located in diverse geographic locations. A base station 105 may have an antenna array with a number of rows and columns of antenna ports that the base station 105 may use to support beamforming of communications with a UE 115. Likewise, a UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, an antenna panel may support radio frequency beamforming for a signal transmitted via an antenna port.

The base stations 105 or the UEs 115 may use MIMO communications to exploit multipath signal propagation and increase the spectral efficiency by transmitting or receiving multiple signals via different spatial layers. Such techniques may be referred to as spatial multiplexing. The multiple signals may, for example, be transmitted by the transmitting device via different antennas or different combinations of antennas. Likewise, the multiple signals may be received by the receiving device via different antennas or different combinations of antennas. Each of the multiple signals may be referred to as a separate spatial stream and may carry bits associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords) . Different spatial layers may be associated with different antenna ports used for channel measurement and reporting. MIMO techniques include single-user MIMO (SU-MIMO) , where multiple spatial layers are transmitted to the same receiving device, and multiple-user MIMO (MU-MIMO) , where multiple spatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering, directional transmission, or directional reception, is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., a base station 105, a UE 115) to shape or steer an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining the signals communicated via antenna elements of an antenna array such that some signals propagating at particular orientations with respect to an antenna array experience constructive interference while others experience destructive interference. The adjustment of signals communicated via the antenna elements may include a transmitting device or a receiving device applying amplitude offsets, phase offsets, or both to signals carried via the antenna elements associated with the device. The adjustments associated with each of the antenna elements may be defined by a beamforming weight set associated with a particular orientation (e.g., with respect to the antenna array of the transmitting device or receiving device, or with respect to some other orientation) .

A base station 105 or a UE 115 may use beam sweeping techniques as part of beam forming operations. For example, a base station 105 may use multiple antennas or antenna arrays (e.g., antenna panels) to conduct beamforming operations for directional communications with a UE 115. Some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted by a base station 105 multiple times in different directions. For example, the base station 105 may transmit a signal according to different beamforming weight sets associated with different directions of transmission. Transmissions in different beam directions may be used to identify (e.g., by a transmitting device, such as a base station 105, or by a receiving device, such as a UE 115) a beam direction for later transmission or reception by the base station 105.

Some signals, such as data signals associated with a particular receiving device, may be transmitted by a base station 105 in a single beam direction (e.g., a direction associated with the receiving device, such as a UE 115) . In some examples, the beam direction associated with transmissions along a single beam direction may be determined based on a signal that was transmitted in one or more beam directions. For example, a UE 115 may receive one or more of the signals transmitted by the base station 105 in different directions and may report to the base station 105 an indication of the signal that the UE 115 received with a highest signal quality or an otherwise acceptable signal quality.

In some examples, transmissions by a device (e.g., by a base station 105 or a UE 115) may be performed using multiple beam directions, and the device may use a combination of digital precoding or radio frequency beamforming to generate a combined beam for transmission (e.g., from a base station 105 to a UE 115) . The UE 115 may report feedback that indicates precoding weights for one or more beam directions, and the feedback may correspond to a configured number of beams across a system bandwidth or one or more sub-bands. The base station 105 may transmit a reference signal (e.g., a cell-specific reference signal (CRS) , a channel state information (CSI) reference signal (CSI-RS) ) , which may be precoded or unprecoded. The UE 115 may provide feedback for beam selection, which may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., a multi-panel type codebook, a linear combination type codebook, a port selection type codebook) . Although these techniques are described with reference to signals transmitted in one or more directions by a base station 105, a UE 115 may employ similar techniques for transmitting signals multiple times in different directions (e.g., for identifying a beam direction for subsequent transmission or reception by the UE 115) or for transmitting a signal in a single direction (e.g., for transmitting data to a receiving device) .

A receiving device (e.g., a UE 115) may try multiple receive configurations (e.g., directional listening) when receiving various signals from the base station 105, such as synchronization signals, reference signals, beam selection signals, or other control signals. For example, a receiving device may try multiple receive directions by receiving via different antenna subarrays, by processing received signals according to different antenna subarrays, by receiving according to different receive beamforming weight sets (e.g., different directional listening weight sets) applied to signals received at multiple antenna elements of an antenna array, or by processing received signals according to different receive beamforming weight sets applied to signals received at multiple antenna elements of an antenna array, any of which may be referred to as “listening” according to different receive configurations or receive directions. In some examples, a receiving device may use a single receive configuration to receive along a single beam direction (e.g., when receiving a data signal) . The single receive configuration may be aligned in a beam direction determined based on listening according to different receive configuration directions (e.g., a beam direction determined to have a highest signal strength, highest signal-to-noise ratio (SNR) , or otherwise acceptable signal quality based on listening according to multiple beam directions) .

The wireless communications system 100 may be a packet-based network that operates according to a layered protocol stack. In the user plane, communications at the bearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based. A Radio Link Control (RLC) layer may perform packet segmentation and reassembly to communicate over logical channels. A Medium Access Control (MAC) layer may perform priority handling and multiplexing of logical channels into transport channels. The MAC layer may also use error detection techniques, error correction techniques, or both to support retransmissions at the MAC layer to improve link efficiency. In the control plane, the Radio Resource Control (RRC) protocol layer may provide establishment, configuration, and maintenance of an RRC connection between a UE 115 and a base station 105 or a core network 130 supporting radio bearers for user plane data. At the physical layer, transport channels may be mapped to physical channels.

The UEs 115 and the base stations 105 may support retransmissions of data to increase the likelihood that data is received successfully. Hybrid automatic repeat request (HARQ) feedback is one technique for increasing the likelihood that data is received correctly over a communication link 125. HARQ may include a combination of error detection (e.g., using a cyclic redundancy check (CRC) ) , forward error correction (FEC) , and retransmission (e.g., automatic repeat request (ARQ) ) . HARQ may improve throughput at the MAC layer in poor radio conditions (e.g., low signal-to-noise conditions) . In some examples, a device may support same-slot HARQ feedback, where the device may provide HARQ feedback in a specific slot for data received in a previous symbol in the slot. In other cases, the device may provide HARQ feedback in a subsequent slot, or according to some other time interval.

The wireless communications system 100 may support communications over unlicensed spectrum (e.g., “contention-based” spectrum) . In the context of unlicensed spectrum, wireless devices (e.g., base stations) may perform LBT procedures and/or channel access contention procedures in order to “win” access to a COT within an FFP of the unlicensed spectrum. For example, a base station may perform a channel access contention procedure within a CCA resource in order to compete for use of a COT, and may subsequently perform communications within the COT based on winning access to the COT via the channel access contention procedure. In the context of a Category 1 (Cat 1) LBT procedure for frame-based equipment (FBE) , a base station 105 and/or a UE 115 may transmit a downlink message (e.g., downlink burst) and/or uplink message (e.g., uplink burst) , respectively, within the COT if a gap (e.g., time gap) from a previous downlink/uplink message (e.g., downlink/uplink burst) is within 16 μs. Moreover, it is noted herein that neither base stations 105 nor UEs 115 may initiate COTs with Cat 1 LBT procedures.

Comparatively, in the context of a Category 2 (Cat 2) LBT procedure for FBE, a base station 105 may initiate a COT at a fixed location/position preceding an FFP in the time domain, whereas a UE 115 may not be able to initiate a COT in Cat 2 LBT procedures. Additionally, a base station 105 and/or a UE 115 may transmit a downlink message (e.g., downlink burst) and/or uplink message (e.g., uplink burst) , respectively, within the COT if a gap (e.g., time gap) from a previous downlink/uplink message (e.g., downlink/uplink burst) is greater than 16 μs. It is noted herein that the time periods for transmitting messages within COTs are different for load-based equipment (LBE) as compared to FBE (e.g., 25 μs for LBE, compared to 16 μs for FBE) . Moreover, in the context of Cat 2 LBT procedures for LBE, base stations 105 and UEs 115 may be configured to perform a measurement 9 μs before performing a message, where the measurement is performed for at least 4 μs.

In some aspects, an FBE mode of operation may be indicated in remaining minimum system information (RMSI) (e.g., semi-static channel access) . In FBE operation, wireless devices (e.g., UEs 115, base stations 105) may perform channel sensing at fixed time instances. If a channel is determined to be busy, the respective wireless devices may back off for a fixed time period, and perform additional channel sensing after the fixed time period. An FFP configuration for unlicensed spectrum may be indicated via a system information broadcast (SIB) message (e.g., SIB-1) . Additionally, or alternatively, an FFP configuration for unlicensed spectrum may be signaled to a UE 115 via RRC signaling (e.g., UE-specific RRC signaling) for FBE secondary cell (SCell) use cases. An FFP configuration may indicate various parameters associated with FFPs in the context of unlicensed spectrum, including a duration of FFPs, starting positions of FFPs, durations and/or positions of idle periods within the respective FFPs, and the like. In some aspects, an FFP duration may include 1 ms, 2 ms, 2.5 ms, 4 ms, 5 ms, and 10 ms. The FFP duration may include the duration of an idle period within the respective FFP.

In some implementations, a starting position of FFPs within every two radio frames may start from an even radio frame, and may be given by i*P, where

and where P defines the FFP duration in ms. The idle period within an FFP for a given subcarrier spacing (SCS) of the unlicensed spectrum may be given by SCS=ceil (Min _idle T _s) , where T _s is the symbol duration for the given SCS, and Min _idle defines the minimum idle period per FFP which is allowed by applicable regulations and is determined by Min _idle=max (5%of FFP, 100 μs) . A physical random access channel (PRACH) resource may be considered to be invalid if it overlaps with an idle period of an FFP when FBE operation is active/indicated.

In some implementations, UE 115 signaling within an FFP may occur if downlink signals (e.g., synchronization signal block (SSB) messages, RMSI signaling) and/or downlink channels (e.g., physical downlink control channel (PDCCH) , group-common-PDCCH (GC-PDCCH) ) within the FFP are detected. For fallback downlink/uplink grants in context of FBE operation, and in cases where the network indicates LBT procedures with Cat 4 or Cat 2 25 μs, the UE 115 may follow the mechanism in which a 9 μs slot is measured within a 25 μs interval, as described herein. The same 2-bit field for an LBT mode of operation may be used for FBE LBT operation, cyclic prefix (CP) extension, and cell association and power control (CAPC) indication. Additionally, fallback downlink control information (DCI) may be used for RMSI scheduling in cases where the UE 115 does not know the network is operating within FBE operation.

Some wireless communications systems may be configured with “fixed COTs, ” in which CCA resources (e.g., CCA resources with duration of 9 μs) used to compete for the use of the fixed COTs are located at the same position for each FFP. In some cases, fixed COTs may begin at the beginning of each FFP, so that transmissions may only begin at the beginning of an FFP. As such, idle periods (e.g., idle periods with a minimum duration of Min _ifle=max (5%of FFP, 100 μs) ) may occur at the end of each FFP. The CCA resource for fixed COTs may be positioned immediately preceding the start of each FFP, so that channel sensing is performed at a fixed location for each FFP (e.g., channel sensing right before the start of the FFP) . In such cases, because the COTs are located at the same position within each FFP, all wireless devices (e.g., base stations 105) may perform channel access contention procedures at the same time (e.g., within the same CCA resources) , and may have an equal probability of gaining access to the COT. However, such equal access may be ill-suited in cases where base stations 105 exhibit varying priorities, and in cases where it may be beneficial to give higher-priority base stations 105 improved access to resources of unlicensed spectrum.

Some other wireless communications systems may be configured with “floating COTs, ” in which CCA resources used to compete for the use of the floating COTs are located at varying positions from one FFP to another. In some cases, floating COTs may begin within a minimum idle period starting from the beginning of an FFP. CCA resources may be offset (e.g., random CCA offset) from a beginning of a COT. As such, an idle period of an FFP with a minimum duration of Min _ifle=max (5%of FFP, 100 μs) may be positioned before and after a floating COT, with a first portion of the idle period positioned before the COT in the time domain, and a second portion of the idle period positioned after the COT in the time domain. With floating COTs, a position of CCA resources in the time domain may be different from FFP to FFP. Floating COTs may enable different wireless devices to compete for use of the COT at different times, and may enable some wireless devices to have a higher probability of gaining access to the respective COTs. However, current wireless communications systems do not support configurations or other rules which enable base stations to select CCA resources and compete for floating COTs based on relative priorities between the base stations.

Accordingly, the base stations 105 and the UEs 115 of the wireless communications system 100 may support priority-based channel access techniques for COTs associated with unlicensed spectrum. More specifically, the base stations 105 and the UEs 115 of the wireless communications system 100 may support techniques which enable base stations 105 to select CCA resources associated with floating COTs based on relative priorities between the respective base stations 105.

For example, a base station 105 of the wireless communications system 100 may be configured to determine its channel access priority, and may select a position and/or an energy detection threshold associated with a CCA resource based on its determined channel access priority. The selected position may define a position of the CCA resource within the FFP in the time domain. The base station 105 may subsequently perform a channel access contention procedure for a COT within the FFP based on the selected position/energy detection threshold of the CCA resource, and may communicate with UEs 115 during the COT based on a result of the channel access contention procedure (e.g., based on winning use of the COT via the channel access contention procedure) .

In some aspects, a base station 105 may be associated with a single channel access priority (e.g., “semi-static” priority) which remains constant from FFP to FFP. In other cases, the channel access priority of the base station 105 may change based on a priority of communications scheduled to be performed by the base station (e.g., “dynamic” priority) . According to some implementations, higher-priority base stations 105 may be configured to select earlier CCA resource positions as compared to lower-priority base stations 105. Additionally, or alternatively, higher-priority base station s 105 may be configured to select higher energy detection thresholds as compared to lower-priority base stations 105. In some aspects, upon winning use of a COT, a base station 105 may transmit (or cause a UE 115 to transmit) receiver protection signals within selected CCA resources of lower-priority base stations 105 in order to prevent the lower-priority base stations 105 from interfering with communications performed during the COT.

Techniques described herein may enable more efficient and reliable usage of unlicensed spectrum. In particular, by enabling higher-priority base stations 105 to select earlier CCA resource positions and/or higher energy detection thresholds, techniques described herein may increase the likelihood that the higher-priority base stations 105 may successfully win the ability to communicate within floating COTs of unlicensed spectrum. As such, the described techniques may reduce a latency of higher-priority communications and/or communications associated with higher-priority base stations 105, thereby improving resource utilization within unlicensed spectrum.

FIG. 2 illustrates an example of a wireless communications system 200 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. In some examples, wireless communications system 200 may implement, or be implemented by, aspects of wireless communications system 100.

The wireless communications system 200 may include a first base station 105-a, a second base station 105-b, and a UE 115-a, which may be examples base stations 105 and UEs 115 as described with reference to FIG. 1. The UE 115-a may communicate with the first base station 105-a and the second base station 105-b using communication links 205-a and 205-b, respectively. The communication links 205-a, 205-b may be examples of an NR or LTE link between the UE 115-a and the respective base stations 105. In some cases, the communication links 205-a, 205-b between the UE 115-a and the base stations 105-a, 105-b may include examples of access links (e.g., Uu link) which may include bi-directional links that enable both uplink and downlink communication. For example, the UE 115-a may transmit uplink signals, such as uplink control signals or uplink data signals, to the first base station 105-a using the communication link 205-a and the first base station 105-a may transmit downlink signals, such as downlink control signals or downlink data signals, to the UE 115-ausing the communication link 205-a. Similarly, the first base station 105-a, 105-b may communicate with one another via a communication link 205-c, which may be an example of a communication link of an X2 interface between the respective base stations 105.

In some aspects, the base stations 105 and the UEs 115 of the wireless communications system 200 may support priority-based channel access techniques for COTs associated with unlicensed spectrum. More specifically, the base stations 105 and the UEs 115 of the wireless communications system 200 may support techniques which enable base stations 105 to select CCA resources associated with floating COTs based on relative priorities (e.g., channel access priorities) between the respective base stations 105. According to some implementations, higher-priority base stations 105 may be configured to select earlier CCA resource positions as compared to lower-priority base stations 105, higher energy detection thresholds as compared to lower-priority base stations 105, or both. By enabling higher-priority base stations 105 to select earlier CCA resource positions and/or higher energy detection thresholds, techniques described herein may increase the likelihood that the higher-priority base stations 105 may successfully win the ability to communicate within floating COTs of unlicensed spectrum.

For example, the first base station 105-a, the second base station 105-b, and the UE 115-a may be configured to communicate via unlicensed spectrum (e.g., NR-U) which includes, or is associated with, a set of FFPs 210. In some aspects, the unlicensed spectrum may be configured with floating COTs 215. In this regard, a relative position of a COT 215 within each FFP 210 may change from one FFP 210 to another, and from one base station 105 to another. The first base station 105-a and the second base station 105-b may be configured to “compete” for use of the floating COTs 215 within the respective FFPs 210 by performing channel access contention procedures (e.g., LBT procedures) within CCA resources 220 associated with the respective COTs 215.

In some aspects, the base stations 105-a, 105-b may be configured to select various parameters associated with CCA resources 220 of the respective COTs 215 based on channel access priorities associated with the respective base stations 105-a, 105-b. In particular, the base stations 105-a, 105-b may be configured to select positions of CCA resources 220 within the respective FFPs 210 based on channel access priorities associated with the respective base stations 105-a, 105-b. Additionally, or alternatively, the base stations 105-a, 105-b may be configured to select energy detection thresholds of CCA resources 220 within the respective FFPs 210 based on channel access priorities associated with the respective base stations 105-a, 105-b.

As will be described in further detail herein, enabling the base stations 105-a, 105-b to select positions and/or energy detection thresholds of the CCA resources 220 may enable higher-priority base stations 105 a higher probability to gain access to a COT 215, and thereby enable higher-priority base stations 105 improved access to resources associated with unlicensed spectrum.

The relative channel access priorities of the base stations 105-a, 105-b may be determined according to one or more channel access priority schemes. Channel access priority schemes may include “semi-static channel access priority schemes” in which the relative channel access priorities of the respective base stations 105-a, 105-b are determined semi-statically, and “dynamic channel access priority schemes” in which the relative channel access priorities of the respective base stations 105-a, 105-b are determined dynamically (e.g., based on a relative priority of communications scheduled to be performed in the respective FFPs 210) . Semi-static channel access priority schemes and dynamic channel access priority schemes will be discussed in further detail herein with respect to FIGs. 3 and 4, respectively.

Channel access priorities associated with respective base stations 105 may define a relative priority/importance of the respective base stations 105 for performing communications over the unlicensed spectrum relative to other base stations 105. In some aspects, base stations 105 with higher channel access priorities may have higher priority/importance for performing communications over the unlicensed spectrum relative to lower-priority base stations 105.

In a semi-static channel access priority scheme, the base stations 105-a, 105-b may be associated with a “semi-static” channel access priority which remains constant from one FFP 210 to another. For example, under a semi-static channel access priority scheme, the first base station 105-a and the second base station 105-b may be associated with a first channel access priority and a second channel access priority, respectively, where the first and second channel access priorities remain constant for a set of FFPs 210. In other words, the first and second channel access priorities associated with the first and second base stations 105-a, 105-b, respectively, may remain constant from the first FFP 210-a to the second FFP 210-b. In such cases, the channel access priorities associated with base stations 105 may be determined based on pre-configured criteria, operators associated with the respective base stations 105-a, 105-b, radio access technologies associated with the respective base stations 105-a, 105-b, or any combination thereof.

Under a semi-static channel access priority scheme, if the first base station 105-a exhibits a higher channel access priority as compared to the second base station 105-b, the first base station 105-a may have a higher channel access priority for accessing resources of the unlicensed spectrum for each FFP 210 (e.g., first FFP 210-a, 210-b) of the set of FFPs 210 of the unlicensed spectrum. As such, under a semi-static channel access priority scheme, the relative channel access priorities of the base stations 105-a, 105-b remain constant.

Conversely, in a dynamic channel access priority scheme, the base stations 105-a, 105-b may each be associated with a “dynamic” channel access priority which may change from one FFP 210 to another. In particular, under a dynamic channel access priority scheme, the relative channel access priorities associated with the respective base stations 105-a, 105-b may be based on a relative priority of communications which are scheduled to be performed by the respective base stations 105-a, 105-b within a given FFP 210. Communication priorities may indicate a relative priority or importance of individual communications or messages which are scheduled to be performed, where communications with a higher priority are associated with a higher communication priority, and communications with a lower priority are associated with a lower priority.

For example, the first base station 105-a may be scheduled to perform a first communication (e.g., downlink/uplink message) during the first FFP 210-a, and the second base station 105-a may be scheduled to perform a second communication (e.g., downlink/uplink message) during the first FFP 210-a, where the first and second communications are associated with first and second communication priorities, respectively. In this example, the first base station 105-a may be associated with a first channel access priority for the first FFP 210-a based on the first communication priority of the first scheduled communication, and the second base station 105-b may be associated with a second channel access priority for the first FFP 210-a based on the second communication priority of the second scheduled communication. As such, the relative channel access priorities of the base stations 105-a, 105-b for the first FFP 210-a may be dynamically based on the relative communication priorities of communications scheduled to be performed by the respective base stations 105-a, 105-b during the first FFP 210-a.

Continuing with the same example, the first base station 105-a may be scheduled to perform a third communication during the second FFP 210-b, and the second base station 105-a may be scheduled to perform a fourth communication during the second FFP 210-b, where the third and fourth communications are associated with third and fourth communication priorities, respectively. In this example, the first base station 105-a may be associated with a third channel access priority for the second FFP 210-b based on the third communication priority of the third scheduled communication, and the second base station 105-b may be associated with a fourth channel access priority for the fourth FFP 210-a based on the fourth communication priority of the fourth scheduled communication. As such, under a dynamic channel access priority scheme, the relative channel access priorities of the base stations 105-a, 105-b change from one FFP 210 to another based on the relative communication priorities of communications scheduled to be performed by the respective base stations 105-a, 105-b during each FFP 210.

In some aspects, upon determining channel access priorities associated with the first base station 105-a and/or the second base station 105-b, the base stations 105 may select at least one of a position or an energy detection threshold associated with a CCA resource 220 of the first FFP 210-a. In particular, the first base station 105-a may select at least one of a position or an energy detection threshold of a first CCA resource 220-a associated with the first base station 105-a, and the second base station 105-a may select at least one of a position or an energy detection threshold of a second CCA resource 220-b associated with the second base station 105-b. As noted previously herein, the position of a CCA resource 220 may define a starting point of the respective CCA resource 220 within the respective FFP 210 in the time domain.

In some aspects, the base stations 105-a, 105-b may select at least one of a position or an energy detection threshold associated with a CCA resource 220-a, 220-b of the first FFP 210-a in accordance with (e.g., based on) the channel access priority associated with the respective base stations 105-a, 105-b. Moreover, the base stations 105-a, 105-b may select at least one of a position or an energy detection threshold of the CCA resources 220-a, 220-b based on (e.g., in accordance) with the channel access priority scheme (e.g., semi-static channel access priority scheme, dynamic channel access priority scheme) .

In some aspects, the selected position of the CCA resources 220-a, 220-b may be selected from a set of position candidates (e.g., set of pre-configured position candidates) . Similarly, the selected energy detection thresholds of the CCA resources 220-a, 220-b may be selected from a set of energy detection threshold candidates (e.g., set of pre-configured energy detection threshold candidates) . In some aspects, the set of position candidates and/or the set of energy detection threshold candidates may be pre-configured at the base stations 105-a, 105-b, determined by the first and/or second base station 105-a, 105-b, signaled to the base stations 105-a, 105-b by the network, or any combination thereof.

In some aspects, higher-priority base stations 105 may be configured to select earlier CCA resources 220 within a respective FFP 210 as compared to lower-priority base stations 105. Additionally, in some implementations, higher-priority base stations 105 may be configured to select higher energy detection thresholds for a CCA resource 220 within a given FFP 210 as compared to lower-priority base stations 105. Selection of earlier CCA positions and/or higher energy detection thresholds may enable higher-priority base stations improved access to floating COTs 215, and therefore improved access to resources of the unlicensed spectrum.

For example, in cases where the first base station 105-a determines that it has a higher channel access priority for the first FFP 210-a compared to the second base station 105-b, the first base station 105-a may select a position of the first CCA resource 220-a within the first FFP 210-a which is earlier in the time domain relative to a second position of the second CCA resource 220-b which is selected by the second base station 105-b. In other words, the first base station 105-a may select the first CCA resource 220-a which is earlier in the time domain relative to the second CCA resource 220-abased on the first base station 105-a having a higher channel access priority. By selecting an earlier CCA resource 220-a, the first base station 105-a (e.g., higher-priority base station 105-a) may be able to perform a channel access contention procedure earlier compared to the second base station 105-b (e.g., lower-priority base station 105-b) , which may give the first base station 105-a a higher probability of winning access of the COT 215 for the first FFP 210-a as compared to the second base station 105-b.

By way of another example, in cases where the first base station 105-adetermines that it has a higher channel access priority for the first FFP 210-a compared to the second base station 105-b, the first base station 105-a may select a higher (e.g., greater) energy detection threshold for the first CCA resource 220-a compared to a second energy detection threshold for the second CCA resource 220-b which is selected by the second base station 105-b. In other words, the first base station 105-a may select higher energy detection threshold based for the first CCA resource 220-a compared to a second energy detection threshold for the second CCA resource 220-b based on the first base station 105-a having a higher channel access priority. Selecting a higher energy detection threshold for the CCA resource 220-a, the first base station 105-a (e.g., higher-priority base station 105-a) may give the first base station 105-a a higher probability of winning access of the COT 215 for the first FFP 210-a as compared to the second base station 105-b.

Upon selecting a position and/or energy detection threshold associated with the CCA resources 220-a, 220-b of the first FFP 210-a, the base stations 105-a, 105-b may perform channel access contention procedures within the respective CCA resources 220-a, 220-b in order to compete for access to COTs 215 within the first FFP 210-a. The base stations 105-a, 105-b may perform the channel access contention procedures based on (e.g., in accordance with) the selected positions and/or energy detection thresholds for the respective CCA resources 220-a, 220-b. The base stations 105-a, 105-b may then communicate (or refrain from communicating) within a COT 215-a of the first FFP 210-a in accordance with a result of the channel access contention procedures (e.g., based on whether or not the respective channel access contention procedures were successful) .

For example, as shown in FIG. 2, the first base station 105-a may be configured to perform a channel access contention procedure (e.g., CCA procedure, LBT procedure) within the first CCA resource 220-a of the first FFP 210-a. In this example, due to the fact that the first base station 105-a had a higher channel access priority, and selected an earlier position and/or higher energy detection threshold of the first CCA resource 220-a as compared to the second CCA resource 220-b, the first base station 105-a may win access to a COT 215-a within the first FFP 210-a. The first base station 105-a may subsequently perform communications with the UE 115-a within the COT 215-a in accordance with a result of the channel access contention procedure (e.g., based on winning access to the COT 215-a within the first FFP 210-a) . For example, the first base station 105-a may receive an uplink message 225 from the UE 115-a within the COT 215-a of the first FFP 210-a. By way of another example, the first base station 105-a may transmit a downlink message 230 to the UE 115-a within the COT 215-a of the first FFP 210-a.

In some aspects, the UE 115-a and/or the base station 105-a may be configured to transmit a receiver protection signal 240 (e.g., “filler signal” ) during the second CCA resource 220-b of the second base station 105-b (e.g., lower-priority base station 105-b) in order to prevent the second base station 105-b from interfering with communications performed by the first base station 105-a during the COT 215-a. For example, in cases where the first UE 115-c wins access of the COT 215-a within the first FFP 210-a, receiver protection signals 240 (e.g., “filler signals” ) may be used to prevent lower-priority base stations 105 (e.g., the second base station 105-b) from attempting to gain access to a COT 215 within the first FFP 210-a and/or interfering with communications performed by the first base station 105-a within the COT 215-a. In particular, receiver protection signals 240 may be transmitted within CCA resources 220 of lower-priority base stations 105 (e.g., the second base station 105-b) in order to prevent the lower-priority base stations from successfully performing channel access contention procedures.

For example, the first base station 105-a may determine a set of time/frequency resources associated with the second CCA resource 220-b of the second base station105-b, and may transmit a receiver protection signal 240-a to the second base station 105-b within a set of resources which at least partially overlap with the CCA resource 220-b in the time domain, the frequency domain, or both. By transmitting the receiver protection signal 240-a, the first base station 105-a may prevent the second base station 105-b from successfully completing a channel access contention procedure within the second CCA resource 220-b. The use of receiver protection signals 240 will be shown and described in further detail with respect to FIG. 5.

By way of another example, the first base station 105-a may transmit control signaling 235 (e.g., RRC signaling, DCI message, MAC-CE message) to the UE 115-a, where the control signaling 235 indicates a set of resources associated with a receiver protection signal 240-b, and an instruction/indication for the UE 115-a to transmit the receiver protection signal 240-b within the set of resources. In some aspects, the first base station 105-a may transmit the control signaling 235 based on winning access of the COT 215-a within the first FFP 210-a. In this example, the first base station 105-a (e.g., higher-priority base station 105) may determine the position of a second CCA resource 220-b associated with the second base station 105-b (e.g., lower-priority base station 105) within the first FFP 210-a, and may transmit control signaling 235 which instructs the UE 115-a to transmit a receiver protection signal 240-b during a resource which at least partially overlaps with the second CCA resource 220-b associated with the second base station 105-b in order to prevent the second base station 105-b (e.g., lower-priority base station 105) from successfully performing a channel access contention procedure for the first FFP 210-a and interfering with communications (e.g., uplink message 225, downlink message 230) performed at the first base station 105-aduring the COT 215-a.

In some cases where the channel access priority of the base stations 105-a, 105-b is determined semi-statically (e.g., semi-static channel access priority scheme) , the selected position and/or selected energy detection threshold of the CCA resources 220 may be applicable for the set of multiple FFPs 210 of the unlicensed spectrum including the first FFP 210-a and the second FFP 210-b. In other words, in the context of a semi-static channel access priority scheme, the selected position and/or energy detection threshold of CCA resources 220 associated with the first base station 105-amay be the same across the first FFP 210-a and the second FFP 210-b. Similarly, the selected position and/or energy detection threshold of CCA resources 220 associated with the second base station 105-b may be the same across the first FFP 210-a and the second FFP 210-b.

For example, under a semi-static channel access priority scheme, the first base station 105-a may be configured to perform a channel access contention procedure within a third CCA resource 220-c of the second FFP 210-b, where the position and/or energy detection threshold of the third CCA resource 220-c is the same as the position/energy detection threshold of the first CCA resource 220-a. Similarly, under a semi-static channel access priority scheme, the second base station 105-b may be configured to perform a channel access contention procedure within a fourth CCA resource 220-d of the second FFP 210-b, where the position and/or energy detection threshold of the fourth CCA resource 220-d is the same as the position/energy detection threshold of the second CCA resource 220-b.

Conversely, in cases where the channel access priorities of the base stations 105-a, 105-b are determined dynamically based on a priority of scheduled communications (e.g., dynamic channel access priority scheme) , the selected position and/or selected energy detection threshold of the CCA resources 220-c, 220-d may be different as compared to the selected position and/or selected energy detection threshold of the CCA resources 220-a, 220-b.

For example, the first base station 105-a may determine a second communication priority associated with a second communication to be performed within the second FFP 210-b, and may determine a second channel access priority associated with the first base station 105-a for the second FFP 210-b based on the second communication priority. Subsequently, the first base station 105-a may compare its determined second channel access priority for the second FFP 210-b to an additional channel access priority associated with the second base station 105-b for the second FFP 210-b, and may select a position and/or energy detection threshold of the third CCA resource 220-c based on (e.g., in accordance with) its second channel access priority for the second FFP 210-b. In this regard, under a dynamic channel access priority scheme, the position and/or energy detection thresholds of the CCA resource 220-c and CCA resource 220-d may be different from the position and/or energy detection thresholds of the CCA resource 220-c and CCA resource 220-d, respectively. This will be described in further detail with respect to FIG. 4.

Subsequently, upon determining the position and/or energy detection thresholds of the CCA resources 220-c, 220-d, the base stations 105-a, 105-b may perform channel access contention procedures within the CCA resources 220-c, 220-d in order to compete for access of COTs 215 within the second FFP 210-b. The base stations 105-a, 105-b may then communicate (or refrain from communicating) with the UE 115-a based on (e.g., in accordance with) the channel access contention procedures performed within the CCA resources 220-c, 220-d.

Techniques described herein may enable more efficient and reliable usage of unlicensed spectrum. In particular, by enabling higher-priority base stations 105 (e.g., first base station 105-a) to select earlier CCA resource 220 positions and/or higher energy detection thresholds, techniques described herein may increase the likelihood that the higher-priority base stations 105 may successfully win the ability to communicate within floating COTs 215 of unlicensed spectrum. As such, the described techniques may reduce a latency of higher-priority communications and/or communications associated with higher-priority base stations 105, thereby improving resource utilization within unlicensed spectrum.

FIG. 3 illustrates an example of a resource configuration 300 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. Aspects of the resource configuration 300 may implement, or be implemented by, aspects of the wireless communications system 100, wireless communications system 200, or both.

Resource configuration 300 illustrates semi-static channel access priority schemes 305-a, 305-b, and 305-c which may be implemented by base stations 105 in order to select positions and/or energy detection thresholds of CCA resources 320 which are used to compete for access of COTs 315 within FFPs 310 of unlicensed spectrum. As shown in FIG. 3, UEs 115 and base stations 105 may be configured to communicate using unlicensed spectrum spanning a set of FFPs 310. In some aspects, the unlicensed spectrum may be configured with floating COTs 315. In this regard, a relative position of a COT 315 within each FFP 310 may change from one FFP 310 to another. In some aspects, a first base station 105 (e.g., gNB 1) and a second base station 105 (e.g., gNB 2) may be configured to “compete” for use of the floating COTs 315 within the respective FFPs 310 by performing channel access contention procedures (e.g., LBT procedures) within CCA resources 320 associated with the respective COTs 315. In particular, the base stations 105 may be configured to compete for use of the floating COTs 315 in accordance with one or more of the semi-static channel access priority schemes 305-a, 305-b, 305-c.

In a semi-static channel access priority scheme 305-a, 305-b, 305-c, the base stations 105 may be associated with “semi-static” priorities which remain constant from one FFP 310 to another. For example, the first base station 105 (e.g., gNB 1) may be associated with a first channel access priority and the second base station 105 (e.g., gNB 2) may be associated with a second channel access priority, where the first and second channel access priorities remain constant throughout the sets of FFPs 310 for each semi-static channel access priority scheme 305-a, 305-b, 305-c. In other words, referring to the first semi-static channel access priority scheme 305-a, the first and second channel access priorities associated with the first and second base stations 105, respectively, may remain constant from the first FFP 310-a to the fourth FFP 310-d. Similarly, channel access priorities for the first and second base stations 105 may remain constant throughout the FFPs 310-e, 310-f, 310-g, and 310-h of the second semi-static channel access priority scheme 305-b, and throughout the FFPs 310-i, 310-j, 310-k, and 310-l of the third semi-static channel access priority scheme 305-c.

Under the semi-static channel access priority schemes 305, base stations 105 with higher channel access priorities (e.g., higher-priority base stations 105) may be configured to select earlier positions of CCA resources 320 within FFPs 310 as compared to base stations 105 with lower channel access priorities (e.g., lower-priority base stations 105) . For example, referring to the first semi-static channel access priority scheme 305-a, gNB 1 may be associated with a higher channel access priority as compared to gNB 2. As such, the gNB 1 may be configured to select an earlier CCA resource 320 within each of the FFPs 310-a through FFP 310-d as compared to the position of the CCA resource 320 selected by gNB 2. In other words, gNB 1 may be configured to select earlier CCA resources 320 as compared to gNB 2 based on gNB 1 exhibiting a higher channel access priority.

As shown in the first semi-static channel access priority scheme 305-a, because the channel access priorities of gNB 1 and gNB 2 remain constant from FFP 310-a to FFP 310-d, the relative position of the CCA resources 320 for both the gNB 1 and the gNB 2 may remain constant within the respective FFPs 310. That is, the position of the CCA resources 320 selected by the gNB 1 may remain constant within each of the FFPs 310-a, 310-b, 310-c, and 310-d, and the position of the CCA resources 320 selected by the gNB 2 may remain constant within each of the FFPs 310-a, 310-b, 310-c, and 310-d. By enabling gNB 1 (e.g., the higher-priority base station 105) to select earlier CCA resources 320 within the respective FFPs 310, techniques described herein may improve a likelihood that the gNB 1 will win access of COTs 315 of the respective FFPs 310, and thereby improve access to resources of the unlicensed spectrum.

By way of another example, referring to the second semi-static channel access priority scheme 305-b, gNB 1 may be associated with a higher channel access priority as compared to gNB 2. As such, the gNB 1 may be configured to select a higher energy detection threshold for CCA resources 320 as compared to an energy detection threshold for CCA resources 320 selected by gNB 2. In other words, gNB 1 may be configured to select a greater energy detection threshold for CCA resources 320 as compared to gNB 2 based on gNB 1 exhibiting a higher channel access priority. For instance, as shown in the second semi-static channel access priority scheme 305-b, gNB 1 may be associated with CCA resources 320-a associated with a first energy detection threshold T ₁, and gNB 2 may be associated with CCA resources 320-b associated with a second energy detection threshold T ₂, where the first energy detection threshold is greater than the second energy detection threshold (e.g., T ₁>T ₂) .

As shown in the second semi-static channel access priority scheme 305-b, because the channel access priorities of gNB 1 and gNB 2 remain constant from FFP 310-e to FFP 310-h, the selected energy detection thresholds of the CCA resources 320 for both the gNB 1 and the gNB 2 may remain constant within the respective FFPs 310. That is, the energy detection thresholds of the CCA resources 320-a selected by the gNB 1 may remain constant within each of the FFPs 310-e, 310-f, 310-g, and 310-h, and the energy detection thresholds of the CCA resources 320-b selected by the gNB 2 may remain constant within each of the FFPs 310-e, 310-f, 310-g, and 310-h. By enabling gNB 1 (e.g., the higher-priority base station 105) to select greater energy detection thresholds for CCA resources 320 within the respective FFPs 310, techniques described herein may improve a likelihood that the gNB 1 will win access of COTs 315 of the respective FFPs 310, and thereby improve access to resources of the unlicensed spectrum.

As shown in the second semi-static channel access priority scheme 305-b, the position of the CCA resources 320-a and the CCA resources 320-b associated with the gNB 1 and the gNB 2, respectively, may be located at the same position in the time domain within each of the FFPs 310. That is, gNB 1 may be associated with a first CCA resource 320-a within the first FFP 310-e, gNB 2 may be associated with a second CCA resource 320-b within the first FFP 310-e, where a position of the first CCA resource 320-a and the second CCA resource 320-b within the first FFP 310-a is the same in the time domain.

In some implementations, base stations 105 may select both a position and an energy detection threshold for CCA resources 320 based on determined channel access priorities. For example, as shown in the third semi-static channel access priority scheme 305-c, gNB 1 and gNB 2 may select both a position and an energy detection threshold for CCA resources 320, where the selected position and energy detection thresholds for the respective CCA resources 320 remains constant throughout FFP 310-i, 310-j, 310-k, and 310-l. In particular, gNB 1 may be configured to select a position of CCA resources 320-a which is earlier in the time domain relative to a position of CCA resources 320-b selected by gNB 2 based on gNB 1 exhibiting a higher channel access priority. Moreover, gNB 1 may be configured to select a greater energy detection threshold for CCA resources 320-a as compared to an energy detection threshold for CCA resources 320-b selected by gNB 2 based on gNB 1 exhibiting a higher channel access priority.

FIG. 4 illustrates an example of a resource configuration 400 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. Aspects of the resource configuration 300 may implement, or be implemented by, aspects of the wireless communications system 100, wireless communications system 200, resource configuration 300, or any combination thereof.

Resource configuration 400 illustrates dynamic channel access priority schemes 405-a, 405-b, and 405-c which may be implemented by base stations 105 in order to select positions and/or energy detection thresholds of CCA resources 420 which are used to compete for access of COTs 415 within FFPs 410 of unlicensed spectrum.

As shown in FIG. 4, UEs 115 and base stations 105 may be configured to communicate using unlicensed spectrum spanning a set of FFPs 410. In some aspects, the unlicensed spectrum may be configured with floating COTs 415. In this regard, a relative position of a COT 415 within each FFP 410 may change from one FFP 410 to another. In some aspects, a first base station 105 (e.g., gNB 1) and a second base station 105 (e.g., gNB 2) may be configured to “compete” for use of the floating COTs 415 within the respective FFPs 410 by performing channel access contention procedures (e.g., LBT procedures) within CCA resources 420 associated with the respective COTs 415. In particular, the base stations 105 may be configured to compete for use of the floating COTs 415 in accordance with one or more of the dynamic channel access priority schemes 405-a, 405-b, 405-c.

Under a dynamic channel access priority scheme 405, base stations 105 with higher channel access priorities (e.g., higher-priority base stations 105) may be configured to select earlier positions of CCA resources 420 within FFPs 410 as compared to base stations 105 with lower channel access priorities (e.g., lower-priority base stations 105) . For example, referring to the first dynamic channel access priority scheme 405-a, gNB 1 may be associated with a higher channel access priority as compared to gNB 2. As such, the gNB 1 may be configured to select an earlier CCA resource 420 within each of the FFPs 410-a through FFP 410-d as compared to the CCA resource 420 selected by gNB 2. In other words, gNB 1 may be configured to select earlier CCA resources 420 as compared to gNB 2 based on gNB 1 exhibiting a higher channel access priority.

As compared to semi-static channel access priority schemes 305 illustrated in FIG. 3 in which channel access priorities for base stations 105 remain constant from FFP 310 to FFP 310, channel access priorities for base stations 105 may change from FFP 410 to FFP 410 in accordance with the dynamic channel access priority schemes 405 illustrated in FIG. 4. In particular, channel access priorities for base stations 105 may change from FFP 410 to FFP 410 in accordance with the dynamic channel access priority schemes 405 based on relative priorities of communications scheduled to be performed by the respective base stations 105 within the respective FFPs 410.

For example, referring to the first dynamic channel access priority scheme 405-a, gNB 1 may be scheduled to perform a higher priority communication 425 within the first FFP 410-a (e.g., communication with a higher communication priority) , whereas gNB 2 may be scheduled to perform a lower priority communication 430 within the first FFP 410-a (e.g., communication with a lower communication priority) . As such, gNB 1 may exhibit a higher channel access priority for the first FFP 410-a as compared to gNB 2. Accordingly, gNB 1 may be configured to select a position of a CCA resource 320 within the first FFP 410-a which is earlier in the time domain of the first FFP 410-a as compared to a position of a CCA resource 320 within the first FFP 410-a selected by gNB 2. Selection of the earlier CCA resource 320 within the first FFP 410-a may provide gNB 1 a higher probability of gaining access to a COT 415 within the first FFP 410-a, and therefore improve the probability that the higher priority communication 425 may be performed within the first FFP 410-a.

Continuing with reference to the first dynamic channel access priority scheme 405-a, gNB 1 and gNB 2 may be configured to perform a lower priority communications 425 within the second FFP 410-b (e.g., communications with the same communication priority) . As such, gNB 1 and gNB 2 may exhibit the same channel access priority for the second FFP 410-b, and may therefore be configured to select a same position of CCA resources 420 within the second FFP 410-b. In other words, a position of CCA resources 420 associated with the gNB 1 and gNB 2 within the second FFP 410-b may be the same in the time domain. Due to the fact that the position of the CCA resources 320 for gNB 1 and gNB 2 is the same, gNB 1 and gNB 2 may have equal probabilities of gaining access to a COT 415 within the second FFP 410-b.

Continuing with reference to the first dynamic channel access priority scheme 405-a, gNB 2 may be scheduled to perform a higher priority communication 425 within the third FFP 410-c (e.g., communication with a higher communication priority) , whereas gNB 1 may be scheduled to perform a lower priority communication 430 within the third FFP 410-c (e.g., communication with a lower communication priority) . As such, gNB 2 may exhibit a higher channel access priority for the third FFP 410-c as compared to gNB 1. Accordingly, gNB 2 may be configured to select a position of a CCA resource 320 within the third FFP 410-c which is earlier in the time domain of the third FFP 410-c as compared to a position of a CCA resource 320 within the third FFP 410-c selected by gNB 1. Selection of the earlier CCA resource 320 within the third FFP 410-c may provide gNB 2 a higher probability of gaining access to a COT 415 within the third FFP 410-c, and therefore improve the probability that the higher priority communication 425 may be performed within the third FFP 410-c.

By way of another example, referring to the second dynamic channel access priority scheme 405-b, gNB 1 may be scheduled to perform a higher priority communication 425 within the first FFP 410-e (e.g., communication with a higher communication priority) , whereas gNB 2 may be scheduled to perform a lower priority communication 430 within the first FFP 410-e (e.g., communication with a lower communication priority) . As such, gNB 1 may exhibit a higher channel access priority for the first FFP 410-e as compared to gNB 2. Accordingly, gNB 1 may be configured to select a greater energy detection threshold for a CCA resource 320-a within the first FFP 410-e as compared to an energy detection threshold for a CCA resource 320-b selected by gNB 2. Selection of the greater energy detection threshold for the CCA resource 320-a within the first FFP 410-e may provide gNB 1 a higher probability of gaining access to a COT 415 within the first FFP 410-e, and therefore improve the probability that the higher priority communication 425 may be performed within the first FFP 410-e.

Continuing with reference to the second dynamic channel access priority scheme 405-b, gNB 1 and gNB 2 may be configured to perform a lower priority communications 425 within the second FFP 410-f (e.g., communications with the same communication priority) . As such, gNB 1 and gNB 2 may exhibit the same channel access priority for the second FFP 410-f, and may therefore be configured to select a same energy detection threshold for CCA resources 420-b within the second FFP 410-b. In other words, an energy detection threshold of CCA resources 420-b associated with the gNB 1 and gNB 2 within the second FFP 410-e may be the same. Due to the fact that the energy detection thresholds of the CCA resources 420 for gNB 1 and gNB 2 is the same, gNB 1 and gNB 2 may have equal probabilities of gaining access to a COT 415 within the second FFP 410-e.

Continuing with reference to the first dynamic channel access priority scheme 405-a, gNB 2 may be scheduled to perform a higher priority communication 425 within the third FFP 410-g (e.g., communication with a higher communication priority) , whereas gNB 1 may be scheduled to perform a lower priority communication 430 within the third FFP 410-g (e.g., communication with a lower communication priority) . As such, gNB 2 may exhibit a higher channel access priority for the third FFP 410-g as compared to gNB 1. Accordingly, gNB 2 may be configured to select a greater energy detection threshold for a CCA resource 320-a within the third FFP 410-g as compared to an energy detection threshold for a CCA resource 320-b selected by gNB 1. Selection of the greater energy detection threshold for the CCA resource 320-a within the third FFP 410-g may provide gNB 2 a higher probability of gaining access to a COT 415 within the third FFP 410-g, and therefore improve the probability that the higher priority communication 425 may be performed within the third FFP 410-g.

In some implementations, base stations 105 may select both a position and an energy detection threshold for CCA resources 420 based on determined channel access priorities. For example, as shown in the third dynamic channel access priority scheme 405-c, gNB 1 and gNB 2 may select both a position and an energy detection threshold for CCA resources 420, where the selected position and energy detection thresholds for the respective CCA resources 420 is based on a relative priority (e.g., communication priority) of communications 425, 430 scheduled to be performed by the respective gNBs across FFP 410-i, 410-j, 410-k, and 410-l. In particular, for the first FFP 410-i, gNB 1 may be configured to select a position of CCA resources 420-a which is earlier in the time domain relative to a position of CCA resources 420-b selected by gNB 2 based on gNB 1 being scheduled to perform a higher priority communication 425, and therefore exhibiting a higher channel access priority. Moreover, for the first FFP 410-i, gNB 1 may be configured to select a greater energy detection threshold for CCA resources 420-a as compared to an energy detection threshold for CCA resources 420-b selected by gNB 2 based on gNB 1 being scheduled to perform a higher priority communication 425, and therefore exhibiting a higher channel access priority.

Comparatively, for the second FFP 410-j, gNB 1 and gNB 2 may both be scheduled to perform lower priority communications 430 (e.g., scheduled to perform communications with the same communication priority) , and may therefore exhibit equal channel access priorities for the second FFP 410-j. As such, gNB 1 and gNB 2 may be configured to select the same position of CCA resources 420-b within the second FFP 410-j based on the gNBs exhibiting the same channel access priority for the second FFP 310-j. Moreover, gNB 1 and gNB 2 may be configured to select the same energy detection threshold for CCA resources 420-b within the second FFP 410-j based on the gNBs exhibiting the same channel access priority for the second FFP 310-j.

FIG. 5 illustrates an example of a resource configuration 500 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. Aspects of the resource configuration 500 may implement, or be implemented by, aspects of the wireless communications system 100, wireless communications system 200, resource configuration 300, resource configuration 400, or any combination thereof.

Resource configuration 500 illustrates communication schemes 505-a, 505-b for transmitting receiver protection signals 525. As shown in FIG. 5, UEs 115 and base stations 105 may be configured to communicate using unlicensed spectrum spanning a set of FFPs 510. In some aspects, the unlicensed spectrum may be configured with floating COTs 515. In this regard, a relative position of a COT 515 within each FFP 510 may change from one FFP 510 to another. In some aspects, a first base station 105 (e.g., gNB 1) and a second base station 105 (e.g., gNB 2) may be configured to “compete” for use of the floating COTs 515 within the respective FFPs 510 by performing channel access contention procedures (e.g., LBT procedures) within CCA resources 520 associated with the respective COTs 515. In particular, the base stations 105 may be configured to compete for use of the floating COTs 515 in accordance with one or more of the semi-static channel access priority schemes 305-a, 305-b, 305-c illustrated in FIG. 3 and/or the dynamic channel access priority schemes 405-a, 405-b, 405-c illustrated in FIG. 4.

As noted previously herein, in some implementations, a UE 115 and/or a first base station 105 (e.g., higher-priority base station 105) may be configured to transmit a receiver protection signals 525 (e.g., “filler signals” ) in order to prevent the other base stations 105 (e.g., lower-priority base stations 105) from interfering with communications performed by the first base station 105-a during the COT 415. In particular, UEs 115 and/or base stations 105 may be configured to transmit receiver protection signals 525 during CCA resources 520 of the lower-priority base stations 105 in order to prevent the lower-priority base stations 105 from successfully performing a channel access contention procedure within the CCA resource 520.

For example, referring to the first communication scheme 505-a, gNB 1 may be associated with a higher channel access priority as compared to gNB 2. As such, gNB 1 may perform a channel access contention procedure within a CCA resource 520 of the first FFP 510-a to gain access of a COT 515 within the first FFP 510-a. In this example, gNB 1 may determine a set of time/frequency resources associated with a CCA resource 520 of the gNB 2 within the first FFP 510-a, and may transmit a receiver protection signal 525 within a set of resources which at least partially overlap with the CCA resource 520 of the gNB 2 in the time domain, the frequency domain, or both. As such, the gNB 1 may transmit the receiver protection signal 525 in order to prevent the gNB 2 from successfully performing a channel access contention procedure within the CCA resource 520 of the first FFP 510-a. Subsequently, following the CCA resource 520 of the gNB 2, the gNB 1 may perform communications (e.g., transmit downlink messages, receive uplink messages) within the COT 515 of the first FFP 510-a.

Continuing with this example, in cases where the gNB 1 has additional information to transmit/receive over the unlicensed spectrum, the gNB 1 may perform channel access contention procedures within CCA resources 520 of subsequent FFPs 510 (e.g., FFP 510-b, 510-c, 510-d) , and may transmit receiver protection signals 525 which overlap with CCA resources 520 of the gNB 2 within the subsequent FFPs 510 in order to prevent the gNB 2 from interfering with communications performed by the gNB 1 within COTs 515 of the subsequent FFPs 510.

By way of another example, referring to the second communication scheme 505-b, gNB 1 may be associated with a higher channel access priority as compared to gNB 2. As such, gNB 1 may perform a channel access contention procedure within a CCA resource 520 of the first FFP 510-a to gain access of a COT 515 within the first FFP 510-a. In this example, gNB 1 may determine a set of time/frequency resources associated with a CCA resource 520 of the gNB 2 within the first FFP 510-a. The gNB 1 may transmit a downlink message 530 (e.g., control signaling, RRC message, DCI message, MAC-CE) to the UE 115, where the downlink message 530 indicates for the UE 115 to transmit a receiver protection signal 525. Subsequently, the UE 115 may transmit the receiver protection signal 525 based on (e.g., in response to) receiving the downlink message 530.

In some aspects, the downlink message 530 may indicate a set of resources associated with the receiver protection signal 525. Additionally, or alternatively, the set of resources for the downlink message 530 may be indicated via other control signaling (e.g., RRC signaling, DCI message, MAC-CE) . For instance, in the context of semi-static channel access priority schemes 305, CCA resources 520 for the gNB 1 and/or gNB 2 may be configured at the UE 115 via RRC signaling, and the downlink messages 530 may trigger the UE 115 to transmit the receiver protection signals 525 within the pre-configured resources. Conversely, in the context of dynamic channel access priority schemes 405, downlink messages 530 (e.g., DCI message, MAC-CE) may dynamically indicate the resources for CCA resources 520 of lower-priority base stations 105 (e.g., gNB 2) , and may instruct the UE 115 to transmit the receiver protection signal 525 within the dynamically-indicated resources. Moreover, in some cases, the downlink message 530 may include additional data (e.g., physical uplink shared channel (PUSCH) data) for the UE 115.

As compared to the communication scheme 505-a, the communication scheme 505-b may reduce a duration of time in which the gNB 1 transmits a receiver protection signal 525. In particular, the communication scheme 505-b may enable the gNB 1 to perform communications (e.g., transmit downlink data, receive uplink data) within a duration of the CCA resource 520 of the gNB 2 in the time domain. As such, the communication scheme 505-b may result in a more efficient use of resources at the gNB 1.

As noted previously herein, the UE 115 may transmit the receiver protection signal 525 within a set of resources which at least partially overlap with the CCA resource 520 of the gNB 2 in the time domain, the frequency domain, or both. As such, the UE 115 may transmit the receiver protection signal 525 in order to prevent the gNB 2 from successfully performing a channel access contention procedure within the CCA resource 520 of the first FFP 510-a. Subsequently, following the CCA resource 520 of the gNB 2, the gNB 1 and/or the UE 115 may perform communications (e.g., downlink/uplink messages) within the COT 515 of the first FFP 510-a.

FIG. 6 illustrates an example of a process flow 600 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. In some examples, process flow 600 may implement, or be implemented by, aspects of wireless communications systems 100, wireless communications systems 200, resource configuration 300, resource configuration 400, resource configuration 500, or any combination thereof. For example, the process flow 600 may illustrate a first base station 105-c determining its channel access priority, selecting a position and/or an energy detection threshold of a CCA resource within a first FFP associated with unlicensed spectrum based on the determined channel access priority, and performing a channel access contention procedure for a COT within the first FFP based on the selected position and/or energy detection threshold, as described with reference to FIGs. 1–5.

In some cases, process flow 600 may include a UE 115-b, a first base station 105-c, and a second base station 105-d, which may be examples of corresponding devices as described herein. In particular, the UE 115-b illustrated in FIG. 6 may include an example of the UE 115-a illustrated in FIG. 2. Similarly, the first base station 105-c and the second base station 105-d illustrated in FIG. 6 may include examples of the first base station 105-a and the second base station 105-b, respectively, as illustrated in FIG. 2.

In some examples, the operations illustrated in process flow 600 may be performed by hardware (e.g., including circuitry, processing blocks, logic components, and other components) , code (e.g., software) executed by a processor, or any combination thereof. Alternative examples of the following may be implemented, where some steps are performed in a different order than described or are not performed at all. In some cases, steps may include additional features not mentioned below, or further steps may be added.

At 605, the first base station 105-c may determine a communication priority associated with a communication which is to be performed within a first FFP of a set of FFPs associated with unlicensed spectrum. In some implementations, higher-priority communications may be associated with higher communication priorities, whereas lower-priority communications may be associated with lower communication priorities. In some aspects, the first base station 105-a may be configured to determine the communication priority based on the type of communication to be performed, an index which defines priorities of communications, one or more parameters associated with the communication, or any combination thereof.

At 610, the first base station 105-c may determine a channel access priority associated with the first base station 105-a. In particular, the first base station 105-c may determine a channel access priority associated with the first base station 105-a for the first FFP. The first base station 105-c may determine a channel access priority associated with the first base station 105-c in accordance with a channel access priority scheme associated with the unlicensed spectrum including the set of FFPs.

The channel access priority may define a relative priority/importance of the first base station 105-c for performing communications over the unlicensed spectrum relative to other base stations 105-c. In particular, base stations 105 with higher channel access priorities may have higher priority/importance for performing communications over the unlicensed spectrum relative to lower-priority base stations 105.

In some implementations, the channel access priority associated with the first base station 105-c for the first FFP may be based on a relative priority of communications to be performed by the first base station 105-c within the first FFP (e.g., dynamic priority, dynamic channel access priority scheme) . In other words, the channel access priority of the first base station 105-c may change from FFP to FFP based on the relative priority of communications which are scheduled to be performed by the first base station 105-c within the respective FFPs such that the channel access priority is determined dynamically. For example, the first base station 105-c may determine the channel access priority associated with the first base station 105-c for the first FFP at 610 based on the communication priority for the communication to be performed by the first base station 105-c within the first FFP which was determined at 605. In this example, the channel access priority associated with the first base station 105-c determined at 610 may be applicable for (e.g., associated with) only the first FFP.

In other implementations, the channel access priority associated with the first base station 105-c may include a “semi-static” priority which remains constant from one FFP to another (e.g., semi-static channel access priority scheme) . In such cases, the channel access priorities associated with base stations 105 may be determined based on pre-configured criteria, operators associated with the respective base stations 105, radio access technologies associated with the respective base stations, or any combination thereof. Moreover, in the context of semi-static channel access priorities, the channel access priority of the first base station 105-c may remain constant from one FFP to another FFP, and may therefore be determined without determining the communication priority at 605. In other words, semi-static channel access priorities associated with respective base stations 105 may not be dependent upon relative communication priorities of communications to be performed by the respective base stations 105 within given FFPs. In such cases, the channel access priority associated with the first base station 105-c determined at 610 may be applicable for (e.g., associated with) multiple FFPs.

At 615, the first base station 105-c may compare its determined channel access priority to channel access priorities associated with other base stations. For example, the first base station 105-c may determine its channel access priority which was determined at 610 to a channel access priority associated with the second base station 105-d. In this regard, the first base station 105-c may perform the comparison between channel access priorities at 615 based on the communication priority determined at 605, the channel access priority determined at 610, or both.

As noted previously herein, higher-priority base stations 105 may be associated with higher channel access priorities, whereas lower-priority base stations 105 may be associated with lower channel access priorities. In some implementations, channel access priorities of other base stations 105 may be pre-configured, signaled to the first base station 105-c (e.g., via X2 interface signaling) , or both. Moreover, in the case of dynamic priorities, channel access priorities associated with other base stations 105 (e.g., second base station 105-d) may change from FFP to FFP based on the relative priority (relative communication priorities) of communications to be performed by the respective base stations 105 within the respective FFPs. Alternatively, in the case of semi-static priorities, channel access priorities associated with other base stations 105 (e.g., second base station 105-d) may remain constant from FFP to FFP.

At 620, the first base station 105-c may determine a set of position candidates associated with a set of CCA resources within the set of FFPs. In particular, the first base station 105-c may determine a set of position candidates for CCA resources within each FFP of the set of FFPs. Each position candidate may define a starting point of a CCA resource within an FFP. For example, in cases where the base station 105-c determines five position candidates, each FFP of the set of FFPs may include five different starting points for a CCA resource (e.g., five different CCA resources) . In some aspects, the position candidates may be pre-configured, signaled to the first base station 105-c from other base stations 105 (e.g., second base station 105-c) , signaled to the first base station 105-c from the network, or any combination thereof.

At 625, the first base station 105-c may determine a set of energy detection threshold candidates associated with a set of CCA resources within the set of FFPs. In particular, the first base station 105-c may determine a set of energy detection threshold candidates for CCA resources within each FFP of the set of FFPs. Each energy detection threshold candidate may define an energy detection threshold associated with a CCA resource which is to be used by the respective base stations 105 when performing a channel access contention procedure within the respective CCA resource. For example, in cases where the base station 105-c determines ten energy detection threshold candidates, each CCA resource within each FFP of the set of FFPs may include five possible energy detection thresholds which may be used when performing a channel access contention procedure within the respective CCA resource. In some aspects, the energy detection threshold candidates may be pre-configured, signaled to the first base station 105-c from other base stations 105 (e.g., second base station 105-c) , signaled to the first base station 105-c from the network, or any combination thereof.

At 630, the first base station 105-c may select at least one of a position or an energy detection threshold associated with a first CCA resource of the first FFP. As noted previously herein, the position may define a starting point of the first CCA resource within the first FFP in the time domain. In some aspects, the first base station 105-c may select at least one of a position or an energy detection threshold associated with a first CCA resource of the first FFP in accordance with (e.g., based on) the channel access priority associated with the first base station 105-c which was determined at 610. Moreover, the first base station 105-c may select at least one of a position or an energy detection threshold based on (e.g., in accordance) with the channel access priority scheme (e.g., semi-static channel access priority scheme, dynamic channel access priority scheme) . Additionally, or alternatively, the first base station 105-c may select the position and/or energy detection threshold associated with the first CCA resource at 630 based on determining the communication priority at 605, comparing the determined channel access priority to channel access priorities of other base stations at 615, or any combination thereof.

In some cases where the channel access priority of the first base station 105-c is determined semi-statically (e.g., semi-static channel access priority scheme) , the selected position and/or selected energy detection threshold may be applicable for the set of multiple FFPs of the unlicensed spectrum including the first FFP. In other words, in the context of semi-static channel access priorities, the selected position and/or energy detection threshold of CCA resources may be the same across the multiple FFPs. For example, in the context of semi-static channel access priorities, the position of the CCA resource selected at 630 may be associated with each CCA resource for each FFP of the set of FFPs. Conversely, in cases where the channel access priority of the first base station 105-c is determined dynamically (e.g., dynamic priority) based on a priority of scheduled communications, the selected position and/or selected energy detection threshold may be applicable only for the first FFP, and may be dynamically selected for each respective FFP.

Moreover, in some aspects, the selected position and/or energy detection threshold associated with the first CCA resource may be selected from the set of position candidates and the set of energy detection candidates, respectively. As such, in some cases, the first base station 105-c may select the position and/or energy detection threshold associated with the first CCA resource at 630 based on determining the set of position candidates at 620, determining the set of energy detection threshold candidates at 625, or both.

The first base station 105-c may select the position and/or the energy detection threshold for the first CCA resource at 630 in accordance with (e.g., based on) the channel access priority scheme and its determined channel access priority for the first FFP. In some implementations, higher-priority base stations 105 may be configured to select earlier CCA resources within a respective FFP as compared to lower-priority base stations 105. Additionally, in some implementations, higher-priority base stations 105 may be configured to select higher energy detection thresholds for a CCA resource within a given FFP as compared to lower-priority base stations 105.

For example, in cases where the first base station 105-c determines that it has a higher channel access priority for the first FFP compared to the second base station 105-d, the first base station 105-c may select a position of the first CCA resource within the first FFP which is earlier in the time domain relative to an additional position of an additional CCA resource which is selected by the second base station 105-d. In other words, the first base station 105-c may select an earlier CCA resource based on the first base station 105-c having a higher channel access priority. Conversely, if the first base station 105-c has a lower channel access priority compared to the second base station 105-d, the first base station 105-c may select a later CCA resource relative to a CCA resource selected by the second base station 105-d based on the first base station 105-c having a lower channel access priority.

By way of another example, in cases where the first base station 105-c determines that it has a higher channel access priority for the first FFP compared to the second base station 105-d, the first base station 105-c may select a higher (e.g., greater) energy detection threshold for the first CCA resource within the first FFP compared to an additional energy detection threshold for an additional CCA resource which is selected by the second base station 105-d. In other words, the first base station 105-c may select higher energy detection threshold based on the first base station 105-c having a higher channel access priority. Conversely, if the first base station 105-c has a lower channel access priority compared to the second base station 105-d, the first base station 105-c may select a lower (e.g., lesser, lower) energy detection threshold relative to an energy detection threshold selected by the second base station 105-d based on the first base station 105-c having a lower channel access priority.

At 635, the first base station 105-c may perform a channel access contention procedure for a COT within the first FFP. The first base station 105-c may perform the channel access contention procedure at 635 in order to compete for the ability to perform communications within the COT of the first FFP. The channel access contention procedure may include, but is not limited to, an LBT procedure, a CCA procedure, and the like.

In particular, the first base station 105-c may perform a channel access contention procedure for the COT within the CCA resource of the first FFP and using the position and/or energy detection threshold which were selected at 630. In this regard, the first base station 105-c may perform the channel access contention procedure at 635 based on determining the communication priority at 605, determining the channel access priority at 610, performing the comparison at 615, determining the set of position candidates and/or set of energy detection threshold candidates at 620 and 625, selecting the position and/or energy detection threshold for the first FFP at 630, or any combination thereof.

At 640, the first base station 105-c may transmit control signaling (e.g., RRC signaling, DCI message, MAC-CE message) to the UE 115-b. The control signaling may indicate a set of resources associated with a receiver protection signal, and an instruction/indication for the UE 115-b to transmit a receiver protection signal within the set of resources. In some aspects, the first base station 105-c may transmit the control signaling at 640 based on winning access of the COT within the first FFP via the channel access contention procedure performed at 635.

In cases where the first UE 115-c wins access of the COT within the first FFP, receiver protection signals (e.g., “filler signals” ) may be used to prevent lower-priority base stations 105 (e.g., the second base station 105-d) from attempting to gain access to the COT and/or interfering with communications performed by the first base station 105-c within the COT. In particular, receiver protection signals (e.g., filler signals) may be transmitted within CCA resources of lower-priority base stations 105 (e.g., the second base station 105-d) in order to prevent the lower-priority base stations from successfully performing channel access contention procedures. As will be discussed in further detail herein, receiver protection signals may be transmitted by the UE 115-b, the first base station 105-c, or both.

For example, upon selecting positions and/or energy detection thresholds for CCA resources within the first FFP, the first and second base stations 105-c, 105-d may exchange CCA resource information with one another (e.g., negotiate and synchronize FFP configuration information including selected CCA resource parameters) . In this regard, the first base station 105-c (e.g., higher-priority base station 105) may determine the position of a CCA resource associated with the second base station 105-d (e.g., lower-priority base station 105) within the first FFP. The first base station 105-b may perform channel sensing (e.g., channel access contention procedure) during the position of the CCA resource selected at 630, and may win access of the COT within the first FFP. In this example, the first base station 105-b may transmit control signaling at 640 which instructs the UE 115-b to transmit a receiver protection signal during a resource which at least partially overlaps with the CCA resource associated with the second base station 105-d in order to prevent the second base station 105-d (e.g., lower-priority base station 105) from successfully performing a channel access contention procedure for the first FFP and interfering with communications performed at the first base station 105-c during the COT.

In some cases, the time and frequency resources for transmitting the receiver protection signal may be configured at the UE 115-b via RRC signaling. For example, in cases where the channel access priorities associated with the respective base stations 105 are determined semi-statically, the first base station 105-c may transmit RRC signaling (e.g., control signaling) which indicates the time/frequency resources of CCA resources associated with lower-priority base stations 105 (e.g., the second base station 105-d) . In such cases, the first base station 105-c may transmit the control signaling (e.g., RRC signaling) to the UE 115-b prior to gaining access to the COT.

In other cases, the time and frequency resources for transmitting the receiver protection signal may be indicated dynamically via control signaling, such as DCI messages, MAC-CE messages, or both. In particular, in the context of dynamic channel access priorities, in which the position of CCA resources for the respective base stations 105 change from FFP to FFP, the first base station 105-c may indicate time/frequency resources associated with CCA resources of lower-priority base stations (e.g., the second base station 105-d) dynamically via DCI messaging after winning access to the COT. For example, upon winning access of the COT, the first base station 105-c may determine a position of a CCA resource associated with the second base station 105-d. In this example, the first base station 105-d may transmit a DCI message to the UE 115-b after winning access of the COT and during the COT, where the DCI message indicates time/frequency resources of the CCA resource associated with the second base station 105-d.

At 645, the UE 115-b may transmit a receiver protection signal (e.g., filler signal) to the second base station 105-d (e.g., lower-priority base station) . The UE 115-b may transmit the receiver protection signal based on (e.g., in accordance with, in response to) receiving the control signaling at 640. For example, the UE 115-b may transmit the receiver protection signal within a resource indicated via the control signaling. In some aspects, the resource (s) in which the receiver protection signal is transmitted may at least partially overlaps with a CCA resource associated with the second base station 105-d in the time domain. As such, the UE 115-b may transmit the receiver protection signal in order to prevent, or block, the second base station 105-d (e.g., lower-priority base station 105) from successfully performing a channel access contention procedure for the first FFP, and to prevent the second base station 105-d from interfering with communications performed at the first base station 105-c during the COT.

Additionally, or alternatively, the first base station 105-c may be configured to transmit a receiver protection signal which prevents/blocks lower-priority base stations 105 (e.g., the second base station 105-d) from successfully gaining access to a COT within the first FFP, and prevents lower-priority base stations 105 from interfering with communications at the first base station 105-c. In such cases, the process flow 600 may proceed to 650.

At 650, the base station 105-c may transmit a receiver protection signal (e.g., filler signal) to the second base station 105-d (e.g., lower-priority base station) . In some aspects, the resource (s) in which the receiver protection signal is transmitted may at least partially overlaps with a CCA resource associated with the second base station 105-d in the time domain. As such, the first base station 105-c may transmit the receiver protection signal in order to prevent, or block, the second base station 105-d (e.g., lower-priority base station 105) from successfully performing a channel access contention procedure for the first FFP, and to prevent the second base station 105-d from interfering with communications performed at the first base station 105-c during the COT.

As such, in some cases, the first base station 105-c may transmit the receiver protection signal at 650 based on performing the channel access contention procedure for the first FFP at 635, based on winning access to the COT within the first FFP at 635, based on determining the position of the CCA resource associated with the second base station 105-d within the first FFP, or both.

At 655, the first base station 105-c may communicate with one or more UEs 115 (e.g., the UE 115-b) within the COT of the first FFP. In some aspects, the first base station 105-c may communicate with the UE 115-b within the COT of the first FFP in accordance with a result of the channel access contention procedure performed at 635 (e.g., based on winning access of the COT through the channel access contention procedure) . The base station 105-c may transmit downlink messages to the UE 115-b, receive uplink messages from the UE 115-b, or both.

In some aspects, receiver protection signals transmitted by the UE 115-b at 645, and/or by the first base station 105-c at 650 may prevent the second base station 105-d from interfering with the communications at 655, and may thereby enable the first base station 105-c to perform the communications at 655. As such, the first base station 105-c and the UE 115-b may perform the communications at 655 based on transmitting/receiving the control signaling at 640, transmitting the receiver protection signals at 645 and/or 650, or any combination thereof.

In some aspects, the first base station 105-c may perform at least a subset of the steps/operations of the process flow 600 for subsequent FFPs in order to compete for access of COTs within the subsequent FFPs. The first base station 105-c may perform at least a subset of the steps/operations of the process flow 600 for subsequent FFPs in based on (e.g., in accordance with) the applicable channel access priority scheme (e.g., semi-static channel access priority scheme, dynamic channel access priority scheme) .

For example, in cases where the channel access priority of the base stations 105-c, 105-d are determined semi-statically (e.g., semi-static channel access priority scheme) , the selected position and/or selected energy detection threshold may be applicable for the set of multiple FFPs of the unlicensed spectrum including the first FFP. In other words, in the context of semi-static channel access priorities, the selected position and/or energy detection threshold of CCA resources may be the same across the multiple FFPs. As such, in cases where the base stations 105-c, 105-d determine their channel access priorities semi-statically, the position/energy detection threshold for CCA resources which were selected at 630 may be applicable to subsequent FFPs. Accordingly, the first base station 105-c may be configured to perform channel access procedures within CCA resources of the subsequent FFPs (e.g., a second FFP) , where the position and/or energy detection threshold of the CCA resources of the subsequent FFPs is the same as the position/energy detection threshold selected at 630. Thus, in cases where the first base station 105-c determines its channel access priority semi-statically, the first base station 105-c may be configured to repeat steps 635-655 within subsequent FFPs (e.g., the second FFP) in order to compete for access of COTs within the subsequent FFPs.

Conversely, in cases where the channel access priority of the base stations 105-c, 105-d are determined dynamically based on a priority of scheduled communications (e.g., dynamic channel access priority scheme) , the selected position and/or selected energy detection threshold may be applicable only for the first FFP, and may be dynamically selected for each respective FFP. As such, in cases where the first base station 105-c determines its channel access priority dynamically, the first base station 105-c may be configured to repeat steps 605-655 within subsequent FFPs (e.g., the second FFP) in order to compete for access of COTs within the subsequent FFPs.

For example, the first base station 105-c may determine a second communication priority associated with a second communication to be performed within a second FFP at 605, and may determine a second channel access priority associated with the first base station 105-c for the second FFP at 610 based on the second communication priority. Subsequently, the first base station 105-c may compare its determined second channel access priority to that of other base stations 105 for the second FFP at 615, and may select a position and/or energy detection threshold of a second CCA resource of the second FFP at 630 based on (e.g., in accordance with) its second channel access priority. The first base station 105-c may then perform a channel access contention procedure within the second CCA resource of the second FFP to compete for a second COT within the second FFP at 635, and may perform the communications at 640-655 in cases where the first base station 105-c wins access to the second COT.

Techniques described herein may enable more efficient and reliable usage of unlicensed spectrum. In particular, by enabling higher-priority base stations 105 (e.g., first base station 105-c) to select earlier CCA resource positions and/or higher energy detection thresholds, techniques described herein may increase the likelihood that the higher-priority base stations 105 may successfully win the ability to communicate within floating COTs of unlicensed spectrum. As such, the described techniques may reduce a latency of higher-priority communications and/or communications associated with higher-priority base stations 105, thereby improving resource utilization within unlicensed spectrum.

FIG. 7 shows a block diagram 700 of a device 705 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The device 705 may be an example of aspects of a base station 105 as described herein. The device 705 may include a receiver 710, a transmitter 715, and a communications manager 720. The device 705 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 710 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to techniques for priority-based channel access for COTs) . Information may be passed on to other components of the device 705. The receiver 710 may utilize a single antenna or a set of multiple antennas.

The transmitter 715 may provide a means for transmitting signals generated by other components of the device 705. For example, the transmitter 715 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to techniques for priority-based channel access for COTs) . In some examples, the transmitter 715 may be co-located with a receiver 710 in a transceiver module. The transmitter 715 may utilize a single antenna or a set of multiple antennas.

The communications manager 720, the receiver 710, the transmitter 715, or various combinations thereof or various components thereof may be examples of means for performing various aspects of techniques for priority-based channel access for COTs as described herein. For example, the communications manager 720, the receiver 710, the transmitter 715, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

In some examples, the communications manager 720, the receiver 710, the transmitter 715, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , a field-programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some examples, a processor and memory coupled with the processor may be configured to perform one or more of the functions described herein (e.g., by executing, by the processor, instructions stored in the memory) .

Additionally or alternatively, in some examples, the communications manager 720, the receiver 710, the transmitter 715, or various combinations or components thereof may be implemented in code (e.g., as communications management software or firmware) executed by a processor. If implemented in code executed by a processor, the functions of the communications manager 720, the receiver 710, the transmitter 715, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a central processing unit (CPU) , an ASIC, an FPGA, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting a means for performing the functions described in the present disclosure) .

In some examples, the communications manager 720 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the receiver 710, the transmitter 715, or both. For example, the communications manager 720 may receive information from the receiver 710, send information to the transmitter 715, or be integrated in combination with the receiver 710, the transmitter 715, or both to receive information, transmit information, or perform various other operations as described herein.

The communications manager 720 may support wireless communication at a first base station in accordance with examples as disclosed herein. For example, the communications manager 720 may be configured as or otherwise support a means for determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs. The communications manager 720 may be configured as or otherwise support a means for selecting at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain. The communications manager 720 may be configured as or otherwise support a means for performing a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold. The communications manager 720 may be configured as or otherwise support a means for communicating with one or more UEs within the COT in accordance with a result of the channel access contention procedure.

By including or configuring the communications manager 720 in accordance with examples as described herein, the device 705 (e.g., a processor controlling or otherwise coupled to the receiver 710, the transmitter 715, the communications manager 720, or a combination thereof) may support more efficient and reliable usage of unlicensed spectrum. In particular, by enabling higher-priority base stations 105 (e.g., first base station 105) to select earlier CCA resource positions and/or higher energy detection thresholds, techniques described herein may increase the likelihood that the higher-priority base stations 105 may successfully win the ability to communicate within floating COTs of unlicensed spectrum. As such, the described techniques may reduce a latency of higher-priority communications and/or communications associated with higher-priority base stations 105, thereby improving resource utilization within unlicensed spectrum.

FIG. 8 shows a block diagram 800 of a device 805 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The device 805 may be an example of aspects of a device 705 or a base station 105 as described herein. The device 805 may include a receiver 810, a transmitter 815, and a communications manager 820. The device 805 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 810 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to techniques for priority-based channel access for COTs) . Information may be passed on to other components of the device 805. The receiver 810 may utilize a single antenna or a set of multiple antennas.

The transmitter 815 may provide a means for transmitting signals generated by other components of the device 805. For example, the transmitter 815 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to techniques for priority-based channel access for COTs) . In some examples, the transmitter 815 may be co-located with a receiver 810 in a transceiver module. The transmitter 815 may utilize a single antenna or a set of multiple antennas.

The device 805, or various components thereof, may be an example of means for performing various aspects of techniques for priority-based channel access for COTs as described herein. For example, the communications manager 820 may include a channel access priority manager 825, a CCA resource manager 830, a channel access contention procedure manager 835, a UE communicating manager 840, or any combination thereof. The communications manager 820 may be an example of aspects of a communications manager 720 as described herein. In some examples, the communications manager 820, or various components thereof, may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the receiver 810, the transmitter 815, or both. For example, the communications manager 820 may receive information from the receiver 810, send information to the transmitter 815, or be integrated in combination with the receiver 810, the transmitter 815, or both to receive information, transmit information, or perform various other operations as described herein.

The communications manager 820 may support wireless communication at a first base station in accordance with examples as disclosed herein. The channel access priority manager 825 may be configured as or otherwise support a means for determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs. The CCA resource manager 830 may be configured as or otherwise support a means for selecting at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain. The channel access contention procedure manager 835 may be configured as or otherwise support a means for performing a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold. The UE communicating manager 840 may be configured as or otherwise support a means for communicating with one or more UEs within the COT in accordance with a result of the channel access contention procedure.

FIG. 9 shows a block diagram 900 of a communications manager 920 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The communications manager 920 may be an example of aspects of a communications manager 720, a communications manager 820, or both, as described herein. The communications manager 920, or various components thereof, may be an example of means for performing various aspects of techniques for priority-based channel access for COTs as described herein. For example, the communications manager 920 may include a channel access priority manager 925, a CCA resource manager 930, a channel access contention procedure manager 935, a UE communicating manager 940, a communication priority manager 945, a receiver protection signal manager 950, a control signaling transmitting manager 955, or any combination thereof. Each of these components may communicate, directly or indirectly, with one another (e.g., via one or more buses) .

The communications manager 920 may support wireless communication at a first base station in accordance with examples as disclosed herein. The channel access priority manager 925 may be configured as or otherwise support a means for determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs. The CCA resource manager 930 may be configured as or otherwise support a means for selecting at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain. The channel access contention procedure manager 935 may be configured as or otherwise support a means for performing a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold. The UE communicating manager 940 may be configured as or otherwise support a means for communicating with one or more UEs within the COT in accordance with a result of the channel access contention procedure.

In some examples, to support selecting at least one of the position or the energy detection threshold, the CCA resource manager 930 may be configured as or otherwise support a means for selecting at least one of the position or the energy detection threshold associated with the first CCA resource based on a comparison of the first channel access priority and a second channel access priority associated with a second base station.

In some examples, to support selecting at least one of the position or the energy detection threshold, the CCA resource manager 930 may be configured as or otherwise support a means for selecting the position of the first CCA resource, where the position of the first CCA resource is earlier in the time domain relative to an additional position of an additional CCA resource associated with an additional base station based on the first channel access priority being greater than an additional channel access priority associated with the additional base station, or where the position of the first CCA resource is later in the time domain relative to the additional position of the additional CCA resource associated with the additional base station based on the first channel access priority being less than the additional channel access priority associated with the additional base station.

In some examples, to support selecting at least one of the position or the energy detection threshold, the CCA resource manager 930 may be configured as or otherwise support a means for determining a set of position candidates associated with a set of multiple CCA resources within the set of multiple FFPs, the first CCA resource included within the set of multiple CCA resources, where each position candidate of the set of position candidates defines a starting point of the set of multiple CCA resources within the set of multiple FFPs in the time domain. In some examples, to support selecting at least one of the position or the energy detection threshold, the CCA resource manager 930 may be configured as or otherwise support a means for selecting the position of the first CCA resource from the set of position candidates based on the first channel access priority. In some examples, the selected position is associated with each CCA resource of the set of multiple CCA resources.

In some examples, to support selecting at least one of the position or the energy detection threshold, the CCA resource manager 930 may be configured as or otherwise support a means for selecting the energy detection threshold of the first CCA resource, where the energy detection threshold of the first CCA resource is greater than an additional energy detection threshold of an additional CCA resource associated with an additional base station based on the first channel access priority being greater than an additional channel access priority associated with the additional base station, or where the energy detection threshold of the first CCA resource is less than the additional energy detection threshold of the additional CCA resource associated with the additional base station based on the first channel access priority being less than the additional channel access priority associated with the additional base station.

In some examples, to support selecting at least one of the position or the energy detection threshold, the CCA resource manager 930 may be configured as or otherwise support a means for determining a set of energy detection threshold candidates associated with a set of multiple CCA resources within the set of multiple FFPs, the first CCA resource included within the set of multiple CCA resources. In some examples, to support selecting at least one of the position or the energy detection threshold, the CCA resource manager 930 may be configured as or otherwise support a means for selecting the energy detection threshold of the first CCA resource from the set of energy detection threshold candidates based on the first channel access priority.

In some examples, to support selecting at least one of the position or the energy detection threshold, the CCA resource manager 930 may be configured as or otherwise support a means for determining a set of position candidates associated with the set of multiple CCA resources within the set of multiple FFPs, the first CCA resource included within the set of multiple CCA resources. In some examples, to support selecting at least one of the position or the energy detection threshold, the CCA resource manager 930 may be configured as or otherwise support a means for selecting the position of the first CCA resource from the set of position candidates based on the first channel access priority.

In some examples, the communication priority manager 945 may be configured as or otherwise support a means for determining a communication priority associated with a communication scheduled to be performed by the first base station. In some examples, the channel access priority manager 925 may be configured as or otherwise support a means for determining the first channel access priority based on the communication priority.

In some examples, the communication is scheduled to be performed within the first FFP, and the communication priority manager 945 may be configured as or otherwise support a means for determining an additional communication priority associated with an additional communication scheduled to be performed by the first base station within an additional FFP. In some examples, the communication is scheduled to be performed within the first FFP, and the channel access priority manager 925 may be configured as or otherwise support a means for determining an additional channel access priority associated with the first base station and associated with the additional FFP based on the additional communication priority.

In some examples, the CCA resource manager 930 may be configured as or otherwise support a means for selecting at least one of an additional position or an additional energy detection threshold associated with an additional CCA resource of the additional FFP of the set of multiple FFPs based on the additional channel access priority. In some examples, the channel access contention procedure manager 935 may be configured as or otherwise support a means for performing an additional channel access contention procedure for an additional COT within the additional FFP and within the additional CCA resource and based on the selecting. In some examples, the UE communicating manager 940 may be configured as or otherwise support a means for communicating with one or more UEs within the additional COT in accordance with a result of the additional channel access contention procedure.

In some examples, the receiver protection signal manager 950 may be configured as or otherwise support a means for transmitting a receiver protection signal during an additional CCA resource associated with an additional base station based on performing the channel access contention procedure, where communicating with the one or more UEs is based on transmitting the receiver protection signal.

In some examples, the control signaling transmitting manager 955 may be configured as or otherwise support a means for transmitting, to a UE of the one or more UEs, control signaling including an indication of a resource associated with a receiver protection signal, where the resource at least partially overlaps with an additional CCA resource associated with an additional base station in the time domain, where communicating with the one or more UEs is based on transmitting the control signaling.

FIG. 10 shows a diagram of a system 1000 including a device 1005 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The device 1005 may be an example of or include the components of a device 705, a device 805, or a base station 105 as described herein. The device 1005 may communicate wirelessly with one or more base stations 105, UEs 115, or any combination thereof. The device 1005 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, such as a communications manager 1020, a network communications manager 1010, a transceiver 1015, an antenna 1025, a memory 1030, code 1035, a processor 1040, and an inter-station communications manager 1045. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 1050) .

The network communications manager 1010 may manage communications with a core network 130 (e.g., via one or more wired backhaul links) . For example, the network communications manager 1010 may manage the transfer of data communications for client devices, such as one or more UEs 115.

In some cases, the device 1005 may include a single antenna 1025. However, in some other cases the device 1005 may have more than one antenna 1025, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 1015 may communicate bi-directionally, via the one or more antennas 1025, wired, or wireless links as described herein. For example, the transceiver 1015 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 1015 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 1025 for transmission, and to demodulate packets received from the one or more antennas 1025. The transceiver 1015, or the transceiver 1015 and one or more antennas 1025, may be an example of a transmitter 715, a transmitter 815, a receiver 710, a receiver 810, or any combination thereof or component thereof, as described herein.

The memory 1030 may include random-access memory (RAM) and read-only memory (ROM) . The memory 1030 may store computer-readable, computer-executable code 1035 including instructions that, when executed by the processor 1040, cause the device 1005 to perform various functions described herein. The code 1035 may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, the code 1035 may not be directly executable by the processor 1040 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the memory 1030 may contain, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor 1040 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some cases, the processor 1040 may be configured to operate a memory array using a memory controller. In some other cases, a memory controller may be integrated into the processor 1040. The processor 1040 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 1030) to cause the device 1005 to perform various functions (e.g., functions or tasks supporting techniques for priority-based channel access for COTs) . For example, the device 1005 or a component of the device 1005 may include a processor 1040 and memory 1030 coupled to the processor 1040, the processor 1040 and memory 1030 configured to perform various functions described herein.

The inter-station communications manager 1045 may manage communications with other base stations 105, and may include a controller or scheduler for controlling communications with UEs 115 in cooperation with other base stations 105. For example, the inter-station communications manager 1045 may coordinate scheduling for transmissions to UEs 115 for various interference mitigation techniques such as beamforming or joint transmission. In some examples, the inter-station communications manager 1045 may provide an X2 interface within an LTE/LTE-Awireless communications network technology to provide communication between base stations 105.

The communications manager 1020 may support wireless communication at a first base station in accordance with examples as disclosed herein. For example, the communications manager 1020 may be configured as or otherwise support a means for determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs. The communications manager 1020 may be configured as or otherwise support a means for selecting at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain. The communications manager 1020 may be configured as or otherwise support a means for performing a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold. The communications manager 1020 may be configured as or otherwise support a means for communicating with one or more UEs within the COT in accordance with a result of the channel access contention procedure.

By including or configuring the communications manager 1020 in accordance with examples as described herein, the device 1005 may support techniques for more efficient and reliable usage of unlicensed spectrum. In particular, by enabling higher-priority base stations 105 (e.g., first base station 105) to select earlier CCA resource positions and/or higher energy detection thresholds, techniques described herein may increase the likelihood that the higher-priority base stations 105 may successfully win the ability to communicate within floating COTs of unlicensed spectrum. As such, the described techniques may reduce a latency of higher-priority communications and/or communications associated with higher-priority base stations 105, thereby improving resource utilization within unlicensed spectrum.

In some examples, the communications manager 1020 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the transceiver 1015, the one or more antennas 1025, or any combination thereof. Although the communications manager 1020 is illustrated as a separate component, in some examples, one or more functions described with reference to the communications manager 1020 may be supported by or performed by the processor 1040, the memory 1030, the code 1035, or any combination thereof. For example, the code 1035 may include instructions executable by the processor 1040 to cause the device 1005 to perform various aspects of techniques for priority-based channel access for COTs as described herein, or the processor 1040 and the memory 1030 may be otherwise configured to perform or support such operations.

FIG. 11 shows a block diagram 1100 of a device 1105 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The device 1105 may be an example of aspects of a UE 115 as described herein. The device 1105 may include a receiver 1110, a transmitter 1115, and a communications manager 1120. The device 1105 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 1110 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to techniques for priority-based channel access for COTs) . Information may be passed on to other components of the device 1105. The receiver 1110 may utilize a single antenna or a set of multiple antennas.

The transmitter 1115 may provide a means for transmitting signals generated by other components of the device 1105. For example, the transmitter 1115 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to techniques for priority-based channel access for COTs) . In some examples, the transmitter 1115 may be co-located with a receiver 1110 in a transceiver module. The transmitter 1115 may utilize a single antenna or a set of multiple antennas.

The communications manager 1120, the receiver 1110, the transmitter 1115, or various combinations thereof or various components thereof may be examples of means for performing various aspects of techniques for priority-based channel access for COTs as described herein. For example, the communications manager 1120, the receiver 1110, the transmitter 1115, or various combinations or components thereof may support a method for performing one or more of the functions described herein.

In some examples, the communications manager 1120, the receiver 1110, the transmitter 1115, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include a processor, a DSP, an ASIC, an FPGA or other programmable logic device, a discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure. In some examples, a processor and memory coupled with the processor may be configured to perform one or more of the functions described herein (e.g., by executing, by the processor, instructions stored in the memory) .

Additionally or alternatively, in some examples, the communications manager 1120, the receiver 1110, the transmitter 1115, or various combinations or components thereof may be implemented in code (e.g., as communications management software or firmware) executed by a processor. If implemented in code executed by a processor, the functions of the communications manager 1120, the receiver 1110, the transmitter 1115, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting a means for performing the functions described in the present disclosure) .

In some examples, the communications manager 1120 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the receiver 1110, the transmitter 1115, or both. For example, the communications manager 1120 may receive information from the receiver 1110, send information to the transmitter 1115, or be integrated in combination with the receiver 1110, the transmitter 1115, or both to receive information, transmit information, or perform various other operations as described herein.

The communications manager 1120 may support wireless communication at a UE in accordance with examples as disclosed herein. For example, the communications manager 1120 may be configured as or otherwise support a means for receiving control signaling indicating a CCA resource associated with a second base station, the CCA resource positioned within a FFP of a set of multiple FFPs associated with unlicensed spectrum. The communications manager 1120 may be configured as or otherwise support a means for receiving, from a first base station different from the second base station, a downlink message within a COT of the FFP, where the CCA resource is positioned within the COT in the time domain. The communications manager 1120 may be configured as or otherwise support a means for transmitting a receiver protection signal during the CCA resource associated with the second base station based on receiving the downlink message.

By including or configuring the communications manager 1120 in accordance with examples as described herein, the device 1105 (e.g., a processor controlling or otherwise coupled to the receiver 1110, the transmitter 1115, the communications manager 1120, or a combination thereof) may support techniques for more efficient and reliable usage of unlicensed spectrum. In particular, by enabling higher-priority base stations 105 (e.g., first base station 105) to select earlier CCA resource positions and/or higher energy detection thresholds, techniques described herein may increase the likelihood that the higher-priority base stations 105 may successfully win the ability to communicate within floating COTs of unlicensed spectrum. As such, the described techniques may reduce a latency of higher-priority communications and/or communications associated with higher-priority base stations 105, thereby improving resource utilization within unlicensed spectrum.

FIG. 12 shows a block diagram 1200 of a device 1205 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The device 1205 may be an example of aspects of a device 1105 or a UE 115 as described herein. The device 1205 may include a receiver 1210, a transmitter 1215, and a communications manager 1220. The device 1205 may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses) .

The receiver 1210 may provide a means for receiving information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to techniques for priority-based channel access for COTs) . Information may be passed on to other components of the device 1205. The receiver 1210 may utilize a single antenna or a set of multiple antennas.

The transmitter 1215 may provide a means for transmitting signals generated by other components of the device 1205. For example, the transmitter 1215 may transmit information such as packets, user data, control information, or any combination thereof associated with various information channels (e.g., control channels, data channels, information channels related to techniques for priority-based channel access for COTs) . In some examples, the transmitter 1215 may be co-located with a receiver 1210 in a transceiver module. The transmitter 1215 may utilize a single antenna or a set of multiple antennas.

The device 1205, or various components thereof, may be an example of means for performing various aspects of techniques for priority-based channel access for COTs as described herein. For example, the communications manager 1220 may include a control signaling receiving manager 1225, a downlink message receiving manager 1230, a receiver protection signal manager 1235, or any combination thereof. The communications manager 1220 may be an example of aspects of a communications manager 1120 as described herein. In some examples, the communications manager 1220, or various components thereof, may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the receiver 1210, the transmitter 1215, or both. For example, the communications manager 1220 may receive information from the receiver 1210, send information to the transmitter 1215, or be integrated in combination with the receiver 1210, the transmitter 1215, or both to receive information, transmit information, or perform various other operations as described herein.

The communications manager 1220 may support wireless communication at a UE in accordance with examples as disclosed herein. The control signaling receiving manager 1225 may be configured as or otherwise support a means for receiving control signaling indicating a CCA resource associated with a second base station, the CCA resource positioned within a FFP of a set of multiple FFPs associated with unlicensed spectrum. The downlink message receiving manager 1230 may be configured as or otherwise support a means for receiving, from a first base station different from the second base station, a downlink message within a COT of the FFP, where the CCA resource is positioned within the COT in the time domain. The receiver protection signal manager 1235 may be configured as or otherwise support a means for transmitting a receiver protection signal during the CCA resource associated with the second base station based on receiving the downlink message.

FIG. 13 shows a block diagram 1300 of a communications manager 1320 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The communications manager 1320 may be an example of aspects of a communications manager 1120, a communications manager 1220, or both, as described herein. The communications manager 1320, or various components thereof, may be an example of means for performing various aspects of techniques for priority-based channel access for COTs as described herein. For example, the communications manager 1320 may include a control signaling receiving manager 1325, a downlink message receiving manager 1330, a receiver protection signal manager 1335, or any combination thereof. Each of these components may communicate, directly or indirectly, with one another (e.g., via one or more buses) .

The communications manager 1320 may support wireless communication at a UE in accordance with examples as disclosed herein. The control signaling receiving manager 1325 may be configured as or otherwise support a means for receiving control signaling indicating a CCA resource associated with a second base station, the CCA resource positioned within a FFP of a set of multiple FFPs associated with unlicensed spectrum. The downlink message receiving manager 1330 may be configured as or otherwise support a means for receiving, from a first base station different from the second base station, a downlink message within a COT of the FFP, where the CCA resource is positioned within the COT in the time domain. The receiver protection signal manager 1335 may be configured as or otherwise support a means for transmitting a receiver protection signal during the CCA resource associated with the second base station based on receiving the downlink message.

In some examples, the control signaling includes a RRC message, and the control signaling receiving manager 1325 may be configured as or otherwise support a means for receiving, via the RRC message, the DCI message, or both, an indication of a set of multiple CCA resources associated with the UE, where the set of multiple CCA resources include the CCA resource, and where each CCA resource of the set of multiple CCA resources corresponds to a FFP of the set of multiple FFPs.

FIG. 14 shows a diagram of a system 1400 including a device 1405 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The device 1405 may be an example of or include the components of a device 1105, a device 1205, or a UE 115 as described herein. The device 1405 may communicate wirelessly with one or more base stations 105, UEs 115, or any combination thereof. The device 1405 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, such as a communications manager 1420, an input/output (I/O) controller 1410, a transceiver 1415, an antenna 1425, a memory 1430, code 1435, and a processor 1440. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 1445) .

The I/O controller 1410 may manage input and output signals for the device 1405. The I/O controller 1410 may also manage peripherals not integrated into the device 1405. In some cases, the I/O controller 1410 may represent a physical connection or port to an external peripheral. In some cases, the I/O controller 1410 may utilize an operating system such as

or another known operating system. Additionally or alternatively, the I/O controller 1410 may represent or interact with a modem, a keyboard, a mouse, a touchscreen, or a similar device. In some cases, the I/O controller 1410 may be implemented as part of a processor, such as the processor 1440. In some cases, a user may interact with the device 1405 via the I/O controller 1410 or via hardware components controlled by the I/O controller 1410.

In some cases, the device 1405 may include a single antenna 1425. However, in some other cases, the device 1405 may have more than one antenna 1425, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 1415 may communicate bi-directionally, via the one or more antennas 1425, wired, or wireless links as described herein. For example, the transceiver 1415 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 1415 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 1425 for transmission, and to demodulate packets received from the one or more antennas 1425. The transceiver 1415, or the transceiver 1415 and one or more antennas 1425, may be an example of a transmitter 1115, a transmitter 1215, a receiver 1110, a receiver 1210, or any combination thereof or component thereof, as described herein.

The memory 1430 may include RAM and ROM. The memory 1430 may store computer-readable, computer-executable code 1435 including instructions that, when executed by the processor 1440, cause the device 1405 to perform various functions described herein. The code 1435 may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, the code 1435 may not be directly executable by the processor 1440 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the memory 1430 may contain, among other things, a basic I/O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.

The processor 1440 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof) . In some cases, the processor 1440 may be configured to operate a memory array using a memory controller. In some other cases, a memory controller may be integrated into the processor 1440. The processor 1440 may be configured to execute computer-readable instructions stored in a memory (e.g., the memory 1430) to cause the device 1405 to perform various functions (e.g., functions or tasks supporting techniques for priority-based channel access for COTs) . For example, the device 1405 or a component of the device 1405 may include a processor 1440 and memory 1430 coupled to the processor 1440, the processor 1440 and memory 1430 configured to perform various functions described herein.

The communications manager 1420 may support wireless communication at a UE in accordance with examples as disclosed herein. For example, the communications manager 1420 may be configured as or otherwise support a means for receiving control signaling indicating a CCA resource associated with a second base station, the CCA resource positioned within a FFP of a set of multiple FFPs associated with unlicensed spectrum. The communications manager 1420 may be configured as or otherwise support a means for receiving, from a first base station different from the second base station, a downlink message within a COT of the FFP, where the CCA resource is positioned within the COT in the time domain. The communications manager 1420 may be configured as or otherwise support a means for transmitting a receiver protection signal during the CCA resource associated with the second base station based on receiving the downlink message.

By including or configuring the communications manager 1420 in accordance with examples as described herein, the device 1405 may support techniques for more efficient and reliable usage of unlicensed spectrum. In particular, by enabling higher-priority base stations 105 (e.g., first base station 105) to select earlier CCA resource positions and/or higher energy detection thresholds, techniques described herein may increase the likelihood that the higher-priority base stations 105 may successfully win the ability to communicate within floating COTs of unlicensed spectrum. As such, the described techniques may reduce a latency of higher-priority communications and/or communications associated with higher-priority base stations 105, thereby improving resource utilization within unlicensed spectrum.

In some examples, the communications manager 1420 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the transceiver 1415, the one or more antennas 1425, or any combination thereof. Although the communications manager 1420 is illustrated as a separate component, in some examples, one or more functions described with reference to the communications manager 1420 may be supported by or performed by the processor 1440, the memory 1430, the code 1435, or any combination thereof. For example, the code 1435 may include instructions executable by the processor 1440 to cause the device 1405 to perform various aspects of techniques for priority-based channel access for COTs as described herein, or the processor 1440 and the memory 1430 may be otherwise configured to perform or support such operations.

FIG. 15 shows a flowchart illustrating a method 1500 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The operations of the method 1500 may be implemented by a base station or its components as described herein. For example, the operations of the method 1500 may be performed by a base station 105 as described with reference to FIGs. 1 through 10. In some examples, a base station may execute a set of instructions to control the functional elements of the base station to perform the described functions. Additionally or alternatively, the base station may perform aspects of the described functions using special-purpose hardware.

At 1505, the method may include determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs. The operations of 1505 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1505 may be performed by a channel access priority manager 925 as described with reference to FIG. 9.

At 1510, the method may include selecting at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain. The operations of 1510 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1510 may be performed by a CCA resource manager 930 as described with reference to FIG. 9.

At 1515, the method may include performing a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold. The operations of 1515 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1515 may be performed by a channel access contention procedure manager 935 as described with reference to FIG. 9.

At 1520, the method may include communicating with one or more UEs within the COT in accordance with a result of the channel access contention procedure. The operations of 1520 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1520 may be performed by a UE communicating manager 940 as described with reference to FIG. 9.

FIG. 16 shows a flowchart illustrating a method 1600 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The operations of the method 1600 may be implemented by a base station or its components as described herein. For example, the operations of the method 1600 may be performed by a base station 105 as described with reference to FIGs. 1 through 10. In some examples, a base station may execute a set of instructions to control the functional elements of the base station to perform the described functions. Additionally or alternatively, the base station may perform aspects of the described functions using special-purpose hardware.

At 1605, the method may include determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs. The operations of 1605 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1605 may be performed by a channel access priority manager 925 as described with reference to FIG. 9.

At 1610, the method may include selecting at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority and based on a comparison of the first channel access priority and a second channel access priority associated with a second base station, the position defining a starting point of the first CCA resource within the first FFP in a time domain. The operations of 1610 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1610 may be performed by a CCA resource manager 930 as described with reference to FIG. 9.

At 1615, the method may include performing a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold. The operations of 1615 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1615 may be performed by a channel access contention procedure manager 935 as described with reference to FIG. 9.

At 1620, the method may include communicating with one or more UEs within the COT in accordance with a result of the channel access contention procedure. The operations of 1620 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1620 may be performed by a UE communicating manager 940 as described with reference to FIG. 9.

FIG. 17 shows a flowchart illustrating a method 1700 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The operations of the method 1700 may be implemented by a base station or its components as described herein. For example, the operations of the method 1700 may be performed by a base station 105 as described with reference to FIGs. 1 through 10. In some examples, a base station may execute a set of instructions to control the functional elements of the base station to perform the described functions. Additionally or alternatively, the base station may perform aspects of the described functions using special-purpose hardware.

At 1705, the method may include determining a communication priority associated with a communication scheduled to be performed by the first base station. The operations of 1705 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1705 may be performed by a communication priority manager 945 as described with reference to FIG. 9.

At 1710, the method may include determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a set of multiple FFPs, where the first channel access priority is determined based on the communication priority. The operations of 1710 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1710 may be performed by a channel access priority manager 925 as described with reference to FIG. 9.

At 1715, the method may include selecting at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the set of multiple FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain. The operations of 1715 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1715 may be performed by a CCA resource manager 930 as described with reference to FIG. 9.

At 1720, the method may include performing a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold. The operations of 1720 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1720 may be performed by a channel access contention procedure manager 935 as described with reference to FIG. 9.

At 1725, the method may include communicating with one or more UEs within the COT in accordance with a result of the channel access contention procedure. The operations of 1725 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1725 may be performed by a UE communicating manager 940 as described with reference to FIG. 9.

FIG. 18 shows a flowchart illustrating a method 1800 that supports techniques for priority-based channel access for COTs in accordance with aspects of the present disclosure. The operations of the method 1800 may be implemented by a UE or its components as described herein. For example, the operations of the method 1800 may be performed by a UE 115 as described with reference to FIGs. 1 through 6 and 11 through 14. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may perform aspects of the described functions using special-purpose hardware.

At 1805, the method may include receiving control signaling indicating a CCA resource associated with a second base station, the CCA resource positioned within a FFP of a set of multiple FFPs associated with unlicensed spectrum. The operations of 1805 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1805 may be performed by a control signaling receiving manager 1325 as described with reference to FIG. 13.

At 1810, the method may include receiving, from a first base station different from the second base station, a downlink message within a COT of the FFP, where the CCA resource is positioned within the COT in the time domain. The operations of 1810 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1810 may be performed by a downlink message receiving manager 1330 as described with reference to FIG. 13.

At 1815, the method may include transmitting a receiver protection signal during the CCA resource associated with the second base station based on receiving the downlink message. The operations of 1815 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1815 may be performed by a receiver protection signal manager 1335 as described with reference to FIG. 13.

The following provides an overview of aspects of the present disclosure:

Aspect 1: A method for wireless communication at a first base station, comprising: determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a plurality of FFPs; selecting at least one of a position or an energy detection threshold associated with a first CCA resource of a first FFP of the plurality of FFPs in accordance with the first channel access priority, the position defining a starting point of the first CCA resource within the first FFP in a time domain; performing a channel access contention procedure for a COT within the first FFP and within the first CCA resource using the selected position or the selected energy detection threshold; and communicating with one or more user equipments (UEs) within the COT in accordance with a result of the channel access contention procedure.

Aspect 2: The method of aspect 1, wherein selecting at least one of the position or the energy detection threshold comprises: selecting at least one of the position or the energy detection threshold associated with the first CCA resource based at least in part on a comparison of the first channel access priority and a second channel access priority associated with a second base station.

Aspect 3: The method of any of aspects 1 through 2, wherein selecting at least one of the position or the energy detection threshold comprises: selecting the position of the first CCA resource, wherein the position of the first CCA resource is earlier in the time domain relative to an additional position of an additional CCA resource associated with an additional base station based at least in part on the first channel access priority being greater than an additional channel access priority associated with the additional base station, or wherein the position of the first CCA resource is later in the time domain relative to the additional position of the additional CCA resource associated with the additional base station based at least in part on the first channel access priority being less than the additional channel access priority associated with the additional base station.

Aspect 4: The method of any of aspects 1 through 3, wherein selecting at least one of the position or the energy detection threshold comprises: determining a set of position candidates associated with a plurality of CCA resources within the plurality of FFPs, the first CCA resource included within the plurality of CCA resources, wherein each position candidate of the set of position candidates defines a starting point of the plurality of CCA resources within the plurality of FFPs in the time domain; and selecting the position of the first CCA resource from the set of position candidates based at least in part on the first channel access priority.

Aspect 5: The method of aspect 4, wherein the selected position is associated with each CCA resource of the plurality of CCA resources.

Aspect 6: The method of any of aspects 1 through 5, wherein selecting at least one of the position or the energy detection threshold comprises: selecting the energy detection threshold of the first CCA resource, wherein the energy detection threshold of the first CCA resource is greater than an additional energy detection threshold of an additional CCA resource associated with an additional base station based at least in part on the first channel access priority being greater than an additional channel access priority associated with the additional base station, or wherein the energy detection threshold of the first CCA resource is less than the additional energy detection threshold of the additional CCA resource associated with the additional base station based at least in part on the first channel access priority being less than the additional channel access priority associated with the additional base station.

Aspect 7: The method of any of aspects 1 through 6, wherein selecting at least one of the position or the energy detection threshold comprises: determining a set of energy detection threshold candidates associated with a plurality of CCA resources within the plurality of FFPs, the first CCA resource included within the plurality of CCA resources; and selecting the energy detection threshold of the first CCA resource from the set of energy detection threshold candidates based at least in part on the first channel access priority.

Aspect 8: The method of aspect 7, wherein selecting at least one of the position or the energy detection threshold further comprises: determining a set of position candidates associated with the plurality of CCA resources within the plurality of FFPs, the first CCA resource included within the plurality of CCA resources; and selecting the position of the first CCA resource from the set of position candidates based at least in part on the first channel access priority.

Aspect 9: The method of any of aspects 1 through 8, further comprising: determining a communication priority associated with a communication scheduled to be performed by the first base station; and determining the first channel access priority based at least in part on the communication priority.

Aspect 10: The method of aspect 9, wherein the communication is scheduled to be performed within the first FFP, and wherein the first channel access priority associated with the first base station is associated with the first FFP, the method further comprising: determining an additional communication priority associated with an additional communication scheduled to be performed by the first base station within an additional FFP; and determining an additional channel access priority associated with the first base station and associated with the additional FFP based at least in part on the additional communication priority.

Aspect 11: The method of aspect 10, further comprising: selecting at least one of an additional position or an additional energy detection threshold associated with an additional CCA resource of the additional FFP of the plurality of FFPs based at least in part on the additional channel access priority; performing an additional channel access contention procedure for an additional COT within the additional FFP and within the additional CCA resource and based at least in part on the selecting; and communicating with one or more UEs within the additional COT in accordance with a result of the additional channel access contention procedure.

Aspect 12: The method of any of aspects 1 through 11, further comprising: transmitting a receiver protection signal during an additional CCA resource associated with an additional base station based at least in part on performing the channel access contention procedure, wherein communicating with the one or more UEs is based at least in part on transmitting the receiver protection signal.

Aspect 13: The method of any of aspects 1 through 12, further comprising: transmitting, to a UE of the one or more UEs, control signaling comprising an indication of a resource associated with a receiver protection signal, wherein the resource at least partially overlaps with an additional CCA resource associated with an additional base station in the time domain, wherein communicating with the one or more UEs is based at least in part on transmitting the control signaling.

Aspect 14: A method for wireless communication at a UE, comprising: receiving control signaling indicating a CCA resource associated with a second base station, the CCA resource positioned within a FFP of a plurality of FFPs associated with unlicensed spectrum; receiving, from a first base station different from the second base station, a downlink message within a COT of the FFP, wherein the CCA resource is positioned within the COT in the time domain; and transmitting a receiver protection signal during the CCA resource associated with the second base station based at least in part on receiving the downlink message.

Aspect 15: The method of aspect 14, wherein the control signaling comprises a radio resource control message, a downlink control information message, or both, the method further comprising: receiving, via the radio resource control message, the downlink control information message, or both, an indication of a plurality of CCA resources associated with the UE, wherein the plurality of CCA resources comprise the CCA resource, and wherein each CCA resource of the plurality of CCA resources corresponds to a FFP of the plurality of FFPs.

Aspect 16: An apparatus for wireless communication at a first base station, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method of any of aspects 1 through 13.

Aspect 17: An apparatus for wireless communication at a first base station, comprising at least one means for performing a method of any of aspects 1 through 13.

Aspect 18: A non-transitory computer-readable medium storing code for wireless communication at a first base station, the code comprising instructions executable by a processor to perform a method of any of aspects 1 through 13.

Aspect 19: An apparatus for wireless communication at a UE, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method of any of aspects 14 through 15.

Aspect 20: An apparatus for wireless communication at a UE, comprising at least one means for performing a method of any of aspects 14 through 15.

Aspect 21: A non-transitory computer-readable medium storing code for wireless communication at a UE, the code comprising instructions executable by a processor to perform a method of any of aspects 14 through 15.

It should be noted that the methods described herein describe possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of the methods may be combined.

Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may be described for purposes of example, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques may be applicable to various other wireless communications systems such as Ultra Mobile Broadband (UMB) , Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDM, as well as other systems and radio technologies not explicitly mentioned herein.

Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration) .

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, and not limitation, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) , or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of computer-readable medium. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD) , floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. ”

The term “determine” or “determining” encompasses a wide variety of actions and, therefore, “determining” can include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, a database or another data structure) , ascertaining and the like. Also, “determining” can include receiving (such as receiving information) , accessing (such as accessing data in a memory) and the like. Also, “determining” can include resolving, selecting, choosing, establishing and other such similar actions.

In the appended figures, similar components or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If just the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label, or other subsequent reference label.

The description set forth herein, in connection with the appended drawings, describes example configurations and does not represent all the examples that may be implemented or that are within the scope of the claims. The term “example” used herein means “serving as an example, instance, or illustration, ” and not “preferred” or “advantageous over other examples. ” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. These techniques, however, may be practiced without these specific details. In some instances, known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.

The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

An apparatus for wireless communication at a first base station, comprising:

a processor;

memory coupled with the processor; and

instructions stored in the memory and executable by the processor to cause the apparatus to:

determine a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a plurality of fixed frame periods;

select at least one of a position or an energy detection threshold associated with a first clear channel assessment resource of a first fixed frame period of the plurality of fixed frame periods in accordance with the first channel access priority, the position defining a starting point of the first clear channel assessment resource within the first fixed frame period in a time domain;

perform a channel access contention procedure for a channel occupancy time within the first fixed frame period and within the first clear channel assessment resource using the selected position or the selected energy detection threshold; and

communicate with one or more user equipments (UEs) within the channel occupancy time in accordance with a result of the channel access contention procedure.
The apparatus of claim 1, wherein the instructions to select at least one of the position or the energy detection threshold are executable by the processor to cause the apparatus to:

select at least one of the position or the energy detection threshold associated with the first clear channel assessment resource based at least in part on a comparison of the first channel access priority and a second channel access priority associated with a second base station.
The apparatus of claim 1, wherein the instructions to select at least one of the position or the energy detection threshold are executable by the processor to cause the apparatus to:

select the position of the first clear channel assessment resource, wherein the position of the first clear channel assessment resource is earlier in the time domain relative to an additional position of an additional clear channel assessment resource associated with an additional base station based at least in part on the first channel access priority being greater than an additional channel access priority associated with the additional base station, or wherein the position of the first clear channel assessment resource is later in the time domain relative to the additional position of the additional clear channel assessment resource associated with the additional base station based at least in part on the first channel access priority being less than the additional channel access priority associated with the additional base station.
The apparatus of claim 1, wherein the instructions to select at least one of the position or the energy detection threshold are executable by the processor to cause the apparatus to:

determine a set of position candidates associated with a plurality of clear channel assessment resources within the plurality of fixed frame periods, the first clear channel assessment resource included within the plurality of clear channel assessment resources, wherein each position candidate of the set of position candidates defines a starting point of the plurality of clear channel assessment resources within the plurality of fixed frame periods in the time domain; and

select the position of the first clear channel assessment resource from the set of position candidates based at least in part on the first channel access priority.
The apparatus of claim 4, wherein the selected position is associated with each clear channel assessment resource of the plurality of clear channel assessment resources.
The apparatus of claim 1, wherein the instructions to select at least one of the position or the energy detection threshold are executable by the processor to cause the apparatus to:

select the energy detection threshold of the first clear channel assessment resource, wherein the energy detection threshold of the first clear channel assessment resource is greater than an additional energy detection threshold of an additional clear channel assessment resource associated with an additional base station based at least in part on the first channel access priority being greater than an additional channel access priority associated with the additional base station, or wherein the energy detection threshold of the first clear channel assessment resource is less than the additional energy detection threshold of the additional clear channel assessment resource associated with the additional base station based at least in part on the first channel access priority being less than the additional channel access priority associated with the additional base station.
The apparatus of claim 1, wherein the instructions to select at least one of the position or the energy detection threshold are executable by the processor to cause the apparatus to:

determine a set of energy detection threshold candidates associated with a plurality of clear channel assessment resources within the plurality of fixed frame periods, the first clear channel assessment resource included within the plurality of clear channel assessment resources; and

select the energy detection threshold of the first clear channel assessment resource from the set of energy detection threshold candidates based at least in part on the first channel access priority.
The apparatus of claim 7, wherein the instructions to select at least one of the position or the energy detection threshold are further executable by the processor to cause the apparatus to:

determine a set of position candidates associated with the plurality of clear channel assessment resources within the plurality of fixed frame periods, the first clear channel assessment resource included within the plurality of clear channel assessment resources; and

select the position of the first clear channel assessment resource from the set of position candidates based at least in part on the first channel access priority.
The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

determine a communication priority associated with a communication scheduled to be performed by the first base station; and

determine the first channel access priority based at least in part on the communication priority.
The apparatus of claim 9, wherein the communication is scheduled to be performed within the first fixed frame period, and the instructions are further executable by the processor to cause the apparatus to:

determine an additional communication priority associated with an additional communication scheduled to be performed by the first base station within an additional fixed frame period; and

determine an additional channel access priority associated with the first base station and associated with the additional fixed frame period based at least in part on the additional communication priority.
The apparatus of claim 10, wherein the instructions are further executable by the processor to cause the apparatus to:

select at least one of an additional position or an additional energy detection threshold associated with an additional clear channel assessment resource of the additional fixed frame period of the plurality of fixed frame periods based at least in part on the additional channel access priority;

perform an additional channel access contention procedure for an additional channel occupancy time within the additional fixed frame period and within the additional clear channel assessment resource and based at least in part on the selecting; and

communicate with one or more UEs within the additional channel occupancy time in accordance with a result of the additional channel access contention procedure.
The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit a receiver protection signal during an additional clear channel assessment resource associated with an additional base station based at least in part on performing the channel access contention procedure, wherein communicating with the one or more UEs is based at least in part on transmitting the receiver protection signal.
The apparatus of claim 1, wherein the instructions are further executable by the processor to cause the apparatus to:

transmit, to a UE of the one or more UEs, control signaling comprising an indication of a resource associated with a receiver protection signal, wherein the resource at least partially overlaps with an additional clear channel assessment resource associated with an additional base station in the time domain, wherein communicating with the one or more UEs is based at least in part on transmitting the control signaling.
An apparatus for wireless communication at a user equipment (UE) , comprising:

a processor;

memory coupled with the processor; and

instructions stored in the memory and executable by the processor to cause the apparatus to:

receive control signaling indicating a clear channel assessment resource associated with a second base station, the clear channel assessment resource positioned within a fixed frame period of a plurality of fixed frame periods associated with unlicensed spectrum;

receive, from a first base station different from the second base station, a downlink message within a channel occupancy time of the fixed frame period, wherein the clear channel assessment resource is positioned within the channel occupancy time in the time domain; and

transmit a receiver protection signal during the clear channel assessment resource associated with the second base station based at least in part on receiving the downlink message.
The apparatus of claim 14, wherein the control signaling comprises a radio resource control message, and the instructions are further executable by the processor to cause the apparatus to:

receive, via the radio resource control message, the downlink control information message, or both, an indication of a plurality of clear channel assessment resources associated with the UE, wherein the plurality of clear channel assessment resources comprise the clear channel assessment resource, and wherein each clear channel assessment resource of the plurality of clear channel assessment resources corresponds to a fixed frame period of the plurality of fixed frame periods.
A method for wireless communication at a first base station, comprising:

determining a first channel access priority associated with the first base station in accordance with a channel access priority scheme associated with an unlicensed spectrum associated with a plurality of fixed frame periods;

selecting at least one of a position or an energy detection threshold associated with a first clear channel assessment resource of a first fixed frame period of the plurality of fixed frame periods in accordance with the first channel access priority, the position defining a starting point of the first clear channel assessment resource within the first fixed frame period in a time domain;

performing a channel access contention procedure for a channel occupancy time within the first fixed frame period and within the first clear channel assessment resource using the selected position or the selected energy detection threshold; and

communicating with one or more user equipments (UEs) within the channel occupancy time in accordance with a result of the channel access contention procedure.
The method of claim 16, wherein selecting at least one of the position or the energy detection threshold comprises:

selecting at least one of the position or the energy detection threshold associated with the first clear channel assessment resource based at least in part on a comparison of the first channel access priority and a second channel access priority associated with a second base station.
The method of claim 16, wherein selecting at least one of the position or the energy detection threshold comprises:

selecting the position of the first clear channel assessment resource, wherein the position of the first clear channel assessment resource is earlier in the time domain relative to an additional position of an additional clear channel assessment resource associated with an additional base station based at least in part on the first channel access priority being greater than an additional channel access priority associated with the additional base station, or wherein the position of the first clear channel assessment resource is later in the time domain relative to the additional position of the additional clear channel assessment resource associated with the additional base station based at least in part on the first channel access priority being less than the additional channel access priority associated with the additional base station.
The method of claim 16, wherein selecting at least one of the position or the energy detection threshold comprises:

determining a set of position candidates associated with a plurality of clear channel assessment resources within the plurality of fixed frame periods, the first clear channel assessment resource included within the plurality of clear channel assessment resources, wherein each position candidate of the set of position candidates defines a starting point of the plurality of clear channel assessment resources within the plurality of fixed frame periods in the time domain; and

selecting the position of the first clear channel assessment resource from the set of position candidates based at least in part on the first channel access priority.
The method of claim 19, wherein the selected position is associated with each clear channel assessment resource of the plurality of clear channel assessment resources.
The method of claim 16, wherein selecting at least one of the position or the energy detection threshold comprises:

selecting the energy detection threshold of the first clear channel assessment resource, wherein the energy detection threshold of the first clear channel assessment resource is greater than an additional energy detection threshold of an additional clear channel assessment resource associated with an additional base station based at least in part on the first channel access priority being greater than an additional channel access priority associated with the additional base station, or wherein the energy detection threshold of the first clear channel assessment resource is less than the additional energy detection threshold of the additional clear channel assessment resource associated with the additional base station based at least in part on the first channel access priority being less than the additional channel access priority associated with the additional base station.
The method of claim 16, wherein selecting at least one of the position or the energy detection threshold comprises:

determining a set of energy detection threshold candidates associated with a plurality of clear channel assessment resources within the plurality of fixed frame periods, the first clear channel assessment resource included within the plurality of clear channel assessment resources; and

selecting the energy detection threshold of the first clear channel assessment resource from the set of energy detection threshold candidates based at least in part on the first channel access priority.
The method of claim 22, wherein selecting at least one of the position or the energy detection threshold further comprises:

determining a set of position candidates associated with the plurality of clear channel assessment resources within the plurality of fixed frame periods, the first clear channel assessment resource included within the plurality of clear channel assessment resources; and

selecting the position of the first clear channel assessment resource from the set of position candidates based at least in part on the first channel access priority.
The method of claim 16, further comprising:

determining a communication priority associated with a communication scheduled to be performed by the first base station; and

determining the first channel access priority based at least in part on the communication priority.
The method of claim 24, wherein the communication is scheduled to be performed within the first fixed frame period, and wherein the first channel access priority associated with the first base station is associated with the first fixed frame period, the method further comprising:

determining an additional communication priority associated with an additional communication scheduled to be performed by the first base station within an additional fixed frame period; and

determining an additional channel access priority associated with the first base station and associated with the additional fixed frame period based at least in part on the additional communication priority.
The method of claim 25, further comprising:

selecting at least one of an additional position or an additional energy detection threshold associated with an additional clear channel assessment resource of the additional fixed frame period of the plurality of fixed frame periods based at least in part on the additional channel access priority;

performing an additional channel access contention procedure for an additional channel occupancy time within the additional fixed frame period and within the additional clear channel assessment resource and based at least in part on the selecting; and

communicating with one or more UEs within the additional channel occupancy time in accordance with a result of the additional channel access contention procedure.
The method of claim 16, further comprising:

transmitting a receiver protection signal during an additional clear channel assessment resource associated with an additional base station based at least in part on performing the channel access contention procedure, wherein communicating with the one or more UEs is based at least in part on transmitting the receiver protection signal.
The method of claim 16, further comprising:

transmitting, to a UE of the one or more UEs, control signaling comprising an indication of a resource associated with a receiver protection signal, wherein the resource at least partially overlaps with an additional clear channel assessment resource associated with an additional base station in the time domain, wherein communicating with the one or more UEs is based at least in part on transmitting the control signaling.
A method for wireless communication at a user equipment (UE) , comprising:

receiving control signaling indicating a clear channel assessment resource associated with a second base station, the clear channel assessment resource positioned within a fixed frame period of a plurality of fixed frame periods associated with unlicensed spectrum;

receiving, from a first base station different from the second base station, a downlink message within a channel occupancy time of the fixed frame period, wherein the clear channel assessment resource is positioned within the channel occupancy time in the time domain; and

transmitting a receiver protection signal during the clear channel assessment resource associated with the second base station based at least in part on receiving the downlink message.
The method of claim 29, wherein the control signaling comprises a radio resource control message, a downlink control information message, or both, the method further comprising:

receiving, via the radio resource control message, the downlink control information message, or both, an indication of a plurality of clear channel assessment resources associated with the UE, wherein the plurality of clear channel assessment resources comprise the clear channel assessment resource, and wherein each clear channel assessment resource of the plurality of clear channel assessment resources corresponds to a fixed frame period of the plurality of fixed frame periods.