Long-term sensing for exceptions to medium access restrictions

Abstract

Wireless communication systems and methods are provided for medium access in a shared radio frequency band with long-term sensing of exceptions to medium access restrictions. A wireless communication device performs channel measurements in the shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the performing channel measurements being based on a plurality of spatial directions. The wireless communication device determines whether the channel measurements satisfy criteria for accessing the shared radio frequency band without medium access restrictions. In response to determining that the channel measurements satisfy the criteria, the wireless communication device transmits a first communication signal in the shared radio frequency band in a first spatial direction without the medium access restrictions, the plurality of spatial directions including the first spatial direction.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of U.S. Patent Application No. 17 / 248,179 filed on January 12, 2021 and U.S. Provisional Patent Application No. 62 / 976,337 filed on February 13, 2020, the entire contents of which are incorporated herein by reference as if fully set forth below and for all applicable purposes. Technical Field

[0003] The present application relates to wireless communication systems, and more particularly, to medium access in a shared radio frequency band (eg, in a shared spectrum or an unlicensed spectrum) with long-term sensing of exceptions to medium access restrictions. Background Art

[0004] Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, etc. These systems may be capable of supporting communication with multiple users by sharing available system resources (e.g., time, frequency, and power). A wireless multiple-access communication system may include multiple base stations (BSs), each of which simultaneously supports communication for multiple communication devices (which may be referred to in other aspects as user equipment (UE)).

[0005] To meet the growing demand for expanded mobile broadband connections, wireless communication technology is evolving from Long Term Evolution (LTE) technology to next-generation New Radio (NR) technology, which may be referred to as the fifth generation (5G). For example, NR is designed to provide lower latency, higher bandwidth or higher throughput, and higher reliability than LTE. NR is designed to operate over a wide range of spectrum bands, for example, from low frequency bands below about 1 GHz and mid-frequency bands from about 1 GHz to about 6 GHz, to high frequency bands (e.g., millimeter wave (mmWave) bands. NR is also designed to operate across different spectrum types, from licensed spectrum to unlicensed and shared spectrum. Spectrum sharing enables operators to opportunistically aggregate spectrum to dynamically support high-bandwidth services. Spectrum sharing can extend the benefits of NR technology to operating entities that may not have access to licensed spectrum.

[0006] One method of avoiding collisions when communicating in a shared spectrum or an unlicensed spectrum is to use a listen-before-talk (LBT) process to ensure that a shared channel is idle before sending a signal in the shared channel. For example, a transmitting node may listen to a channel to determine if there is an active transmission in the channel. When the channel is idle, the transmitting node may send a reservation signal (e.g., a preamble) to reserve a channel occupancy time (COT) in the shared channel, and may communicate with a receiving node during the COT. Summary of the invention

[0007] Some aspects of the present disclosure are summarized below to provide a basic understanding of the technology discussed. This summary is not an exhaustive review of all contemplated features of the present disclosure, and is neither intended to identify key or important elements of all aspects of the present disclosure, nor to describe the scope of any or all aspects of the present disclosure. Its sole purpose is to present some concepts of one or more aspects of the present disclosure in a summarized form as a prelude to a more detailed description presented later.

[0008] For example, in one aspect of the present disclosure, a method of wireless communication includes: performing channel measurement in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time by a wireless communication device, wherein the performing of the channel measurement is based on a plurality of spatial directions; determining, by the wireless communication device, whether the channel measurement satisfies a criterion for accessing the shared radio frequency band without medium access restriction; and, in response to determining that the channel measurement satisfies the criterion, sending, by the wireless communication device, a first communication signal in the shared radio frequency band in a first spatial direction without the medium access restriction, the plurality of spatial directions including the first spatial direction.

[0009] In another aspect of the present disclosure, a wireless communication device includes a processor and a transceiver coupled to the processor, the processor being configured to: perform channel measurements in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the channel measurements being based on a plurality of spatial directions; and determine whether the channel measurements satisfy criteria for accessing the shared radio frequency band without medium access restrictions; wherein the transceiver is configured to: in response to determining that the channel measurements satisfy the criteria, send a first communication signal in the shared radio frequency band in the first spatial direction without the medium access restrictions, the plurality of spatial directions including the first spatial direction.

[0010] In another aspect of the present disclosure, a non-transitory computer-readable medium having program code recorded thereon, the program code comprising: code for causing a wireless communication device to perform channel measurement in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the channel measurement being based on a plurality of spatial directions; code for causing the wireless communication device to determine whether the channel measurement satisfies a criterion for accessing a shared radio frequency band without medium access restriction; and code for causing the wireless communication device to send a first communication signal in the shared radio frequency band in a first spatial direction without the medium access restriction in response to determining that the channel measurement satisfies the criterion, the plurality of spatial directions including the first spatial direction.

[0011] In another aspect of the present disclosure, a wireless communication device includes: a unit for performing channel measurements in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the channel measurements being based on a plurality of spatial directions; a unit for determining whether the channel measurements satisfy criteria for accessing the shared radio frequency band without medium access restrictions; and a unit for sending a first communication signal in the shared radio frequency band in a first spatial direction without the medium access restrictions in response to determining that the channel measurements satisfy the criteria, the plurality of spatial directions including the first spatial direction.

[0012] When browsing the following description of the specific, exemplary embodiments of the present invention in conjunction with the accompanying drawings, other aspects, features and embodiments of the present invention will become apparent to those of ordinary skill in the art. Although the features of the present invention can be discussed with respect to certain embodiments and figures below, all embodiments of the present invention may include one or more of the advantageous features discussed herein. In other words, although one or more embodiments may be discussed as features with certain advantages, one or more of such features may also be used according to the various embodiments of the present invention discussed herein. In a similar manner, although the exemplary embodiments may be discussed below as devices, systems or methods, it should be understood that such exemplary embodiments may be implemented in various devices, systems and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A wireless communication network in accordance with some aspects of the present disclosure is shown.

[0014] Figure 2

[0013] A wireless communication network with directional transmitters and receivers in accordance with some aspects of the present disclosure is shown.

[0015] Figure 3A medium access scheme with long-term sensing according to some aspects of the present disclosure is shown.

[0016] Figure 4A A medium access scheme with long-term sensing according to some aspects of the present disclosure is shown.

[0017] Figure 4B Medium access restrictions in accordance with some aspects of the present disclosure are shown.

[0018] Figure 5 is a block diagram of a user equipment (UE) according to some aspects of the present disclosure.

[0019] Figure 6 is a block diagram of an exemplary base station (BS) according to some aspects of the present disclosure.

[0020] Figure 7 is a flow chart of a medium access method with long-term sensing according to some aspects of the present disclosure.

[0021] Figure 8 is a flow chart of a method of wireless communication according to some aspects of the present disclosure. DETAILED DESCRIPTION

[0022] The detailed description set forth below in conjunction with the accompanying drawings is intended as a description of various configurations and is not intended to represent the only configurations that can implement the concepts described herein. The detailed description includes specific details for providing a thorough understanding of the various concepts. However, it is apparent to those skilled in the art that these concepts can be implemented without these specific details. In some instances, well-known structures and components are shown in the form of block diagrams to avoid blurring such concepts.

[0023] In general, the present disclosure relates to wireless communication systems, also referred to as wireless communication networks. In various aspects, these techniques and devices can be used for wireless communication networks such as code division multiple access (CDMA) networks, time division multiple access (TDMA) networks, frequency division multiple access (FDMA) networks, orthogonal FDMA (OFDMA) networks, single carrier FDMA (SC-FDMA) networks, LTE networks, global mobile communication systems (GSM) networks, fifth generation (5G) or new radio (NR) networks, and other communication networks. As described herein, the terms "network" and "system" can be used interchangeably.

[0024] OFDMA network can realize radio technology such as Evolved UTRA (E-UTRA), Institute of Electrical and Electronics Engineers (IEEE) 802.11, IEEE 802.16, IEEE 802.20, Flash OFDM, etc. UTRA, E-UTRA and GSM are parts of Universal Mobile Telecommunications System (UMTS). Specifically, Long Term Evolution (LTE) is a version of UMTS using E-UTRA. UTRA, E-UTRA, GSM, UMTS and LTE are described in documents provided by an organization named "3rd Generation Partnership Project" (3GPP), and cdma2000 is described in documents from an organization named "3rd Generation Partnership Project 2" (3GPP2). These various radio technologies and standards are known or are being developed. For example, the 3rd Generation Partnership Project (3GPP) is a collaboration between telecommunications association groups that aims to define globally applicable third generation (3G) mobile phone specifications. 3GPP Long Term Evolution (LTE) is a 3GPP project aimed at improving UMTS mobile phone standards. 3GPP may define specifications for next generation mobile networks, mobile systems, and mobile devices. The present disclosure relates to the evolution of wireless technologies from LTE, 4G, 5G, NR, and beyond that use new and different radio access technologies or sets of radio air interfaces to share access to wireless spectrum between networks.

[0025] 5G networks envision different deployments, different spectrums, and different services and devices that can be implemented using a unified air interface based on OFDM. To achieve these goals, in addition to developing new radio technologies for 5G NR networks, further enhancements to LTE and LTE-A are also considered. 5G NR will be able to extend to provide coverage from (1) to (2) with ultra-high density (e.g., ~1M nodes / km) 2 ), ultra-low complexity (e.g., ~ tens of bits / second), ultra-low energy consumption (e.g., ~ 10 years of battery life), and deep coverage capable of reaching challenging locations; (2) including mission-critical control for users with strong security to protect sensitive personal, financial, or confidential information, ultra-high reliability (e.g., ~ 99.9999% reliability), ultra-low latency (e.g., ~ 1 ms), and a wide range of mobility or lack of mobility; and (3) with enhanced mobile broadband, including extremely high capacity (e.g., ~ 10 Tbps / km 2 ), extremely high data rates (e.g., multi-Gbps rates, 100+Mbps user experienced rates), and deep perception with advanced discovery and optimization.

[0026] 5G NR can be implemented using an optimized OFDM-based waveform with a scalable digital scheme and transmission time interval (TTI); with a common, flexible framework to effectively multiplex services and features with a dynamic, low-latency time division duplex (TDD) / frequency division duplex (FDD) design; and using advanced wireless technologies such as massive multiple-input multiple-output (MIMO), robust millimeter wave (mmWave) transmission, advanced channel coding, and device-centric mobility. The scalability of the digital scheme in 5G NR and the scaling of the subcarrier spacing can effectively address the operation of various services across different spectrums and different deployments. For example, in various outdoor and macro coverage deployments less than 3GHz FDD / TDD implementations, the subcarrier spacing may appear at 15kHz, for example, on bandwidths (BW) of 5, 10, 20MHz, etc. For other various outdoor and small cell coverage deployments of TDD greater than 3GHz, the subcarrier spacing may appear at 30kHz on 80 / 100MHz BW. For various other indoor broadband implementations, using TDD on the unlicensed portion of the 5 GHz band, subcarrier spacing may occur at 60 kHz over 160 MHz BW. Finally, for various deployments transmitting with a millimeter wave component at 28 GHz TDD, subcarrier spacing may occur at 120 kHz over 500 MHz BW.

[0027] 5G NR's scalable digital scheme facilitates scalable TTI for different latency and quality of service (QoS) requirements. For example, shorter TTIs can be used for low latency and high reliability, while longer TTIs can be used for higher spectral efficiency. Efficient multiplexing of long and short TTIs allows transmissions to start at symbol boundaries. 5G NR also envisions a self-contained integrated subframe design where UL / downlink schedules information, data, and acknowledgments in the same subframe. The self-contained integrated subframe supports communications in unlicensed or contention-based shared spectrum, adaptive UL / downlink that can be flexibly configured on a per-cell basis to dynamically switch between UL and downlink to meet current business needs.

[0028] The various other aspects and features of the present disclosure are further described below. It should be apparent that the teachings of this article can be embodied in a variety of forms, and any specific structure, function, or both disclosed herein are merely representative and non-restrictive. Based on the teachings of this article, it should be understood by those of ordinary skill in the art that the aspects disclosed herein can be implemented independently of any other aspects, and two or more of these aspects can be combined in various ways. For example, using any number of aspects set forth herein, a device can be implemented or a method can be implemented. In addition, using other structures, functions, or structures and functions other than one or more of the aspects set forth herein or structures and functions different from one or more of the aspects set forth herein, such a device can be implemented or such a method can be implemented. For example, a method can be implemented as a part of a system, device, device, and / or implemented as an instruction stored on a computer-readable medium for execution on a processor or computer. In addition, an aspect may include at least one element of a claim.

[0029] To enable coexistence between multiple devices in a shared or unlicensed spectrum, the LBT process can be used to evaluate whether a shared channel is idle before sending a signal in the channel. During the initial phase of the LBT process, the device can perform a clear channel assessment (CCA) for a predetermined duration. During the CCA, the device can compare the energy level detected in the channel with a threshold. If the energy level exceeds the threshold, the device can determine that the channel is occupied, stop sending signals, and repeat the CCA after a period of time, or the device can reduce its transmit power to avoid interfering with other devices that may be using the channel. If the energy level is below the threshold, the device can determine that the channel is not occupied and continue to send signals.

[0030] Although LBT can facilitate medium access in a shared channel, the LBT process can prove inefficient for medium access on the millimeter wave band. For example, due to the high path loss in the millimeter wave band, the operating transmitter and receiver can communicate with each other using directional beams. Since LBT measures the energy in the channel and declares channel occupancy based on the measured channel energy exceeding a threshold, there may be a poor correlation between the transmitter detecting the energy in the channel and the possibility that the transmitter interferes with the receiver of the ongoing communication link. For example, the transmitter may intend to send in one direction, while the receiver of the ongoing communication link may be receiving data from another direction. Therefore, the transmitter can transmit without interfering with the receiver of the ongoing communication link. However, due to the detected channel energy, the transmitter can avoid sending in the channel. In addition, depending on the network deployment, the transmitter and receiver of the base station (BS) may not be in the same location, so the transmitter and receiver can point to different directions for corresponding transmission and reception. Therefore, LBT may not be efficient for medium access on the millimeter wave band.

[0031] The present disclosure provides a technique for medium access in a shared radio frequency band such as a millimeter wave band, with long-term sensing to determine whether a specific medium access restriction such as LBT can be excluded. For example, a wireless communication device (which may be a BS or a UE) may be configured, for example, by a network to have multiple measurement opportunities spaced apart in time for long-term channel measurements. The wireless communication device may perform channel measurements in a shared radio frequency band during multiple measurement opportunities. Channel measurements may be performed in multiple spatial directions. In some cases, the channel measurements may be omnidirectional channel measurements (e.g., in all spatial directions). The wireless communication device may determine whether the channel measurements meet a standard (e.g., a certain threshold) for accessing a shared radio frequency band without medium access restrictions. The medium access restriction may be part of a provision for accessing a shared radio frequency band. In some aspects, the medium access restriction may limit a certain transmission characteristic, such as transmit beam width, transmit power, transmit PSD, transmit duty cycle, and / or the use of LBT before transmission.

[0032] If the long-term channel measurement meets the criteria for accessing the shared radio frequency band without medium access restrictions, the wireless communication device may send communication signals in the shared radio frequency band without medium access restrictions. The communication signal may be sent in a first spatial direction of multiple spatial directions. The wireless communication device may access the shared radio frequency band based on a medium access protocol defined by a radio access technology (RAT) in use.

[0033] If the long-term channel measurements do not meet criteria for accessing the shared radio frequency band without medium access restrictions, the wireless communication device may transmit communication signals in the shared radio frequency band with medium access restrictions.

[0034] In some aspects, all cooperative wireless communication devices operating under a specific RAT may be configured with a measurement opportunity and may perform channel measurements during the measurement opportunity. During the measurement period, the cooperative devices may remain silent (no transmission) so that each cooperative device does not interfere with each other's measurements. Since all cooperative devices remain silent during the measurement period, the cooperative device can determine whether there is a non-cooperative node nearby based on whether the long-term channel measurement meets a certain threshold. When there are non-cooperative devices nearby, the cooperative device can apply medium access restrictions. In other words, medium access restrictions can be applied to inter-RAT medium access, and intra-RAT medium access can be based on the medium access protocol defined by the corresponding RAT.

[0035] Aspects of the present disclosure may provide several benefits. For example, the use of long-term channel sensing may enable medium access restrictions to be applied as needed (e.g., when a nearby non-cooperative device is detected), rather than applying medium access restrictions to each transmission. For example, long-term channel sensing may allow a transmitting device to transmit without performing LBT when no nearby non-cooperative device is detected, thereby avoiding LBT overhead. Alternatively, long-term channel sensing may allow a transmitting device to transmit with unrestricted transmission parameters when no nearby non-cooperative device is detected, thereby providing higher quality transmissions (e.g., in terms of signal-to-noise ratio (SNR) and / or signal-to-interference-plus-noise ratio (SINR)). Therefore, long-term channel sensing may provide more efficient or more effective channel access. Therefore, spectrum utilization efficiency may also be improved.

[0036] Figure 1 A wireless communication network 100 according to some aspects of the present disclosure is shown. The network 100 may be a 5G network. The network 100 includes a plurality of base stations (BSs) 105 (respectively labeled 105a, 105b, 105c, 105d, 105e, and 105f) and other network entities. The BS 105 may be a station that communicates with the UE 115, and may also be referred to as an evolved Node B (eNB), a next generation eNB (gNB), an access point (e.g., IEEE 802.11AP), and the like. Each BS 105 may provide communication coverage for a specific geographic area. In 3GPP, the term "cell" may refer to the specific geographic coverage area of ​​the BS 105 and / or the BS subsystem serving the coverage area, depending on the context in which the term is used.

[0037] BS105 can provide communication coverage for macro cells or small cells (such as pico cells or femto cells) and / or other types of cells. Macro cells generally cover a relatively large geographic area (e.g., a radius of several kilometers) and can allow unrestricted access by UEs with service subscriptions with a network provider. Small cells (such as pico cells) will generally cover a relatively small geographic area and can allow unrestricted access by UEs with service subscriptions with a network provider. Small cells (such as femto cells) will also generally cover a relatively small geographic area (e.g., a residence) and in addition to unrestricted access may also provide restricted access by UEs associated with a femto cell (e.g., UEs in a closed subscriber group (CSG) , UEs of users in a home, etc.). The BS of a macro cell may be referred to as a macro BS. The BS of a small cell may be referred to as a small cell BS, a pico BS, a femto BS, or a home BS. In Figure 1 In the example shown in , BS105d and 105e may be conventional macro BSs, while BS105a-105c may be macro BSs enabled with one of three-dimensional (3D), full-dimensional (FD), or massive MIMO. BS105a-105c may utilize its higher-dimensional MIMO capabilities to employ 3D beamforming in elevation and azimuth beamforming to increase coverage and capacity. BS105f may be a small cell BS, which may be a home node or a portable access point. BS105 may support one or more (e.g., two, three, four, etc.) cells.

[0038] The network 100 may support synchronous or asynchronous operation. For synchronous operation, the BSs may have similar frame timing, and transmissions from different BSs may be approximately aligned in time. For asynchronous operation, the BSs may have different frame timing, and transmissions from different BSs may not be aligned in time.

[0039] UE 115 is scattered throughout the wireless network 100, and each UE 115 can be fixed or mobile. UE 115 can also be referred to as a terminal, a mobile station, a user unit, a station, etc. UE 115 can be a cellular phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a wireless local loop (WLL) station, an IEEE 802.11 terminal station (STA), etc. In one aspect, UE 115 can be a device including a universal integrated circuit card (UICC). In another aspect, UE can be a device that does not include UICC. In some aspects, UE 115 that does not include UICC can also be referred to as an IoT device or an Internet of Everything (IoE) device. UE 115a-115d is an example of a mobile smart phone type device that accesses the network 100. UE 115 can also be a machine that is specially configured for connection communication, and these connection communications include machine type communication (MTC), enhanced MTC (eMTC), narrowband IoT (NB-IoT), etc. UE 115e-115h are examples of various machines configured for communication to access network 100. UE 115i-115k are examples of vehicles equipped with wireless communication devices configured for communication to access network 100. UE 115 may be able to communicate with any type of BS, whether a macro BS, a small cell, or something similar. Figure 1 , the lightning ball (e.g., communication link) indicates wireless transmission between UE 115 and serving BS 105 (which is a BS designated to serve UE 115 on a downlink (DL) and / or uplink (UL), desired transmission between BS 105, backhaul transmission between BSs, or sidelink transmission between UE 115.

[0040] In operation, BS 105a-105c may use 3D beamforming and cooperative spatial techniques such as coordinated multi-point (CoMP) or multi-connectivity to serve UEs 115a and 115b. Macro BS 105d may perform backhaul communications with BS 105a-105c and small cell BS 105f. Macro BS 105d may also transmit multicast services subscribed and received by UEs 115c and 115d. Such multicast services may include mobile TV or streaming video, or may include other services for providing community information, such as weather emergencies or alerts, such as Amber Alerts or Gray Alerts.

[0041] The BS 105 may also communicate with a core network. The core network may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. At least some of the BSs 105 (e.g., which may be examples of gNBs or access node controllers (ANCs)) may interface with the core network via a backhaul link (e.g., NG-C, NG-U, etc.) and may perform radio configuration and scheduling for communications with the UE 115. In various examples, the BSs 105 may communicate with each other directly or indirectly (e.g., via a core network) via a backhaul link (e.g., X1, X2, etc.), which may be a wired or wireless communication link.

[0042] The network 100 may also support mission critical communications with ultra-reliable and redundant links for mission critical devices such as UE 115e, which may be a drone. The redundant communication links with UE 115e may include links from macro BSs 105d and 105e, and links from small cell BS 105f. Other machine type devices such as UE 115f (e.g., a thermometer), UE 115g (e.g., a smart meter), and UE 115h (e.g., a wearable device) may communicate directly with a BS such as small cell BS 105f and macro BS 105e through the network 100, or in a multi-step configuration by communicating with another user device that relays its information to the network, such as UE 115f transmitting temperature measurement information to smart meter UE 115g, which then reports the temperature measurement information to the network through small cell BS 105f. The network 100 may also provide additional network efficiency through dynamic, low-latency TDD / FDD communications, for example, V2V, V2X, C-V2X communications between UE 115i, UE 115j, or UE 115k and other UEs 115, and / or vehicle-to-infrastructure (V2I) communications between UE 115i, UE 115j, or UE 115k and BS 105.

[0043] In some embodiments, the network 100 communicates using an OFDM-based waveform. An OFDM-based system can divide the system BW into multiple (K) orthogonal subcarriers, which are also commonly referred to as subcarriers, tones, frequency bands, etc. Each subcarrier can be modulated with data. In some instances, the subcarrier spacing between adjacent subcarriers can be fixed, and the total number of subcarriers (K) can depend on the system BW. The system BW can also be divided into subbands. In other instances, the subcarrier spacing and / or the duration of the TTI can be scalable.

[0044] In some aspects, BS105 may assign or schedule transmission resources (e.g., in the form of time-frequency resource blocks (RBs)) for downlink (DL) and uplink (UL) transmissions in network 100. DL refers to the transmission direction from BS105 to UE 115, while UL refers to the transmission direction from UE 115 to BS105. Communication may be in the form of radio frames. Radio frames may be divided into multiple (e.g., approximately 10) subframes or time slots. Each time slot may be further divided into micro-time slots. In FDD mode, simultaneous UL and DL transmissions may occur in different frequency bands. For example, each subframe includes a UL subframe in a UL frequency band and a DL subframe in a DL frequency band. In TDD mode, UL and DL transmissions occur at different time periods using the same frequency band. For example, a subset of subframes in a radio frame (e.g., DL subframes) may be used for DL ​​transmissions, while another subset of subframes in a radio frame (e.g., UL subframes) may be used for UL transmissions.

[0045] DL subframes and UL subframes may be further divided into several regions. For example, each DL or UL subframe may have a predefined region for transmitting reference signals, control information, and data. Reference signals are predetermined signals that facilitate communication between BS105 and UE 115. For example, reference signals may have a specific pilot pattern or structure, wherein pilot tones may span the BW or frequency band of operation, and each pilot tone is located at a predefined time and a predefined frequency. For example, BS105 may send a cell-specific reference signal (CRS) and / or a channel state information-reference signal (CSI-RS) to enable UE115 to estimate the DL channel. Similarly, UE 115 may send a sounding reference signal (SRS) to enable BS105 to estimate the UL channel. Control information may include resource assignment and protocol control. Data may include protocol data and / or operational data. In some aspects, BS105 and UE 115 may communicate using self-contained subframes. Self-contained subframes may include a portion for DL ​​communication and a portion for UL communication. A self-contained subframe may be DL-centric or UL-centric. A DL-centric subframe may include a longer duration for DL ​​communications than for UL communications. A UL-centric subframe may include a longer duration for UL communications than for DL ​​communications.

[0046] In some aspects, network 100 may be an NR network deployed on a licensed spectrum. BS 105 may send synchronization signals (e.g., including a primary synchronization signal (PSS) and a secondary synchronization signal (SSS)) in network 100 to facilitate synchronization. BS 105 may broadcast system information associated with network 100 (e.g., including a master information block (MIB), remaining system information (RMSI), and other system information (OSI)) to facilitate initial network access. In some instances, BS 105 may broadcast PSS, SSS, and / or MIB in the form of a synchronization signal block (SSB) on a physical broadcast channel (PBCH), and may broadcast RMSI and / or OSI on a physical downlink shared channel (PDSCH).

[0047] In some aspects, a UE 115 attempting to access the network 100 may perform an initial cell search by detecting a PSS from the BS 105. The PSS may enable synchronization of periodic timing and may indicate a physical layer identification value. The UE 115 may then receive the SSS. The SSS may enable radio frame synchronization and may provide a cell identification value, which may be combined with a physical layer identification value to identify a cell. The PSS and SSS may be located in the center portion of a carrier or in any suitable frequency within a carrier.

[0048] After receiving the PSS and SSS, the UE 115 may receive the MIB. The MIB may include system information for initial network access and scheduling information for RMSI and / or OSI. After decoding the MIB, the UE 115 may receive the RMSI and / or OSI. The RMSI and / or OSI may include radio resource control (RRC) information related to random access channel (RACH) procedures, paging, control resource sets (CORESET) for physical downlink control channel (PDCCH) monitoring, physical UL control channel (PUCCH), physical UL shared channel (PUSCH), power control, and SRS.

[0049] After obtaining the MIB, RMSI and / or OSI, the UE 115 may perform a random access procedure to establish a connection with the BS 105. In some examples, the random access procedure may be a four-step random access procedure. For example, the UE 115 may send a random access preamble, and the BS 105 may respond with a random access response. The random access response (RAR) may include a detected random access preamble identifier (ID) corresponding to the random access preamble, timing advance (TA) information, UL permission, a temporary cell radio network temporary identifier (C-RNTI), and / or a backoff indicator. After receiving the random access response, the UE 115 may send a connection request to the BS 105, and the BS 105 may respond with a connection response. The connection response may indicate a contention resolution method. In some examples, the random access preamble, the RAR, the connection request, and the connection response may be referred to as message 1 (MSG 1), message 2 (MSG 2), message 3 (MSG 3), and message 4 (MSG 4), respectively. In some examples, the random access procedure may be a two-step random access procedure, where the UE 115 may send a random access preamble and a connection request in a single transmission, and the BS 105 may respond by sending a random access response and a connection response in a single transmission.

[0050] After establishing the connection, UE 115 and BS 105 may enter a normal operating state in which operating data may be exchanged. For example, BS 105 may schedule UE 115 for UL and / or DL ​​communications. BS 105 may send UL and / or DL ​​scheduling grants to UE 115 via PDCCH. Scheduling grants may be sent in the form of DL control information (DCI). BS 105 may send DL communication signals (e.g., carrying data) to UE 115 via PDSCH according to the DL scheduling grant. UE 115 may send UL communication signals to BS 105 via PUSCH and / or PUCCH according to the UL scheduling grant.

[0051] In some aspects, BS105 may communicate with UE 115 using HARQ technology to improve communication reliability, for example, to provide URLLC services. BS105 may schedule UE 115 to perform PDSCH communication by sending a DL grant in PDCCH. BS105 may send DL data packets to UE 115 according to the scheduling in PDSCH. DL data packets may be sent in the form of transport blocks (TBs). If UE 115 successfully receives the DL data packet, UE 115 may send HARQ ACK to BS105. On the contrary, if UE 115 fails to successfully receive the DL transmission, UE 115 may send HARQ NACK to BS105. Upon receiving HARQ NACK from UE 115, BS105 may retransmit the DL data packet to UE 115. The retransmission may include the DL data of the same coded version as the initial transmission. Alternatively, the retransmission may include the DL data of the coded version different from the initial transmission. The UE 115 may apply soft combining to combine the coded data received from the initial transmission and the retransmission for decoding. The BS 105 and the UE 115 may also apply HARQ to UL communications using a substantially similar mechanism to DL HARQ.

[0052] In some aspects, the network 100 may operate on a system BW or a component carrier (CC) BW. The network 100 may divide the system BW into multiple BWPs (e.g., parts). The BS 105 may dynamically allocate the UE 115 to operate on a certain BWP (e.g., a certain part of the system BW). The allocated BWP may be referred to as an active BWP. The UE 115 may monitor the active BWP to obtain signaling information from the BS 105. The BS 105 may schedule the UE 115 to perform UL communication or DL ​​communication in the active BWP. In some aspects, the BS 105 may allocate a pair of BWPs within the CC to the UE 115 for UL communication and DL communication. For example, the BWP pair may include a BWP for UL communication and a BWP for DL ​​communication.

[0053] In some aspects, network 100 may operate on a shared channel, which may include a shared frequency band and / or an unlicensed frequency band. For example, network 100 may be an NR-U network operating on an unlicensed frequency band. In such aspects, BS105 and UE 115 may be operated by multiple network operation entities. In order to avoid conflicts, BS105 and UE 115 may monitor transmission opportunities (TXOPs) in a shared channel using a listen-before-talk (LBT) process. TXOP may also be referred to as COT. The goal of LBT is to protect reception at the receiver from interference. For example, a transmitting node (e.g., BS105 or UE115) may perform LBT before transmitting in a channel. When LBT passes, the transmitting node may continue to transmit. When LBT fails, the transmitting node may avoid transmitting in the channel.

[0054] LBT can be based on energy detection (ED) or signal detection. For LBT based on energy detection, when the signal energy measured from the channel is lower than a threshold, the LBT result passes. On the contrary, when the signal energy measured from the channel exceeds a threshold, the LBT result fails. For LBT based on signal detection, when a channel reservation signal (e.g., a predetermined preamble signal) is not detected in the channel, the LBT result passes. In addition, LBT can have multiple modes. The LBT mode can be, for example, Category 4 (CAT4) LBT, Category 2 (CAT2) LBT, or Category 1 (CAT1) LBT. CAT1 LBT is referred to as a no-LBT mode, in which LBT is not performed before transmission. CAT2 LBT refers to LBT without a random backoff period. For example, a transmitting node can determine a channel measurement in a time interval and determine whether a channel is available based on a comparison of the channel measurement with an ED threshold. CAT4 LBT refers to LBT with random backoff and a variable contention window (CW). For example, a transmitting node can extract a random number based on a random number extracted in a certain time unit and back off for a period of time.

[0055] In some aspects, the network 100 may operate in the millimeter wave band (e.g., at 60 GHz). Due to the high path loss in the millimeter wave band, the BS 105 and the UE 115 may communicate with each other using directional beams, such as Figure 2 as shown in .

[0056] Figure 2 A wireless communication network 200 with directional transmitters and receivers according to some aspects of the present disclosure is shown. Network 200 may correspond to a portion of network 100. For simplicity of discussion, Figure 2Two BSs 205 (shown as 205a and 205b) and two UEs 215 (shown as 215a and 215b) are shown, but it will be appreciated that aspects of the present disclosure may be extended to any suitable number of UEs 215 (e.g., approximately 3, 4, 5, 6, 7, 8, 9, 10 or more) and / or BSs 205 (e.g., approximately 3, 4 or more). The BSs 205 and UEs 215 may be similar to the BSs 105 and UEs 115, respectively. The BSs 205 and UEs 215 may communicate via a millimeter wave frequency band. The millimeter wave frequency band may be at any millimeter wave frequency (e.g., 20 GHz, 30 GHz, 60 GHz or higher).

[0057] In network 200, BS 205a can serve UE 215a, and BS 205b can serve UE 215b. In some aspects, BS 205a and UE 215a can be operated by one network operating entity, and BS 205b and UE 215b can be operated by different network operating entities. In some aspects, BS 205a and UE 215a can communicate with each other using one RAT, and BS 205b and UE 215b can communicate with each other using different RATs. For example, BS 205a and UE 215a can be WiFi devices, and BS 205b and UE 215b can be NR-U devices. NR-U can refer to the deployment of NR on unlicensed spectrum.

[0058] exist Figure 2 In the illustrated example, BS 205a may transmit a transmission to UE 215a using transmit beam 202a in a direction 206a along a line of sight (LOS) path 204a. For example, BS 205a may generate directional transmit beam 202a using digital beamforming and / or analog beamforming. BS 205b may transmit a transmission to UE 215b using transmit beam 202b in a different direction 206b along LOS path 204b. Similarly, BS 205b may generate directional transmit beam 202b using digital beamforming and / or analog beamforming.

[0059] As can be seen, BS 205a follows LOS path 204b along which BS 205b transmits to UE 215b. Thus, if BS 205a performs LBT when BS 205b is actively transmitting to UE 215b using transmit beam 202b, BS 205a can detect that the channel energy exceeds a certain LBT threshold, and thus BS 205a can determine that LBT has failed and avoid accessing the channel. However, BS 205a may intend to transmit to UE 215a in direction 206a that is different from direction 206b. Since the transmission is highly directional, BS 205a can transmit to UE 215a using transmit beam 202a without interfering with UE 215b receiving from BS 205b. Therefore, packet-by-packet, energy-detection-based LBT may be ineffective for medium access in the millimeter wave band.

[0060] Thus, the present disclosure provides techniques for determining whether certain medium access restrictions can be excluded when performing medium access on a shared RF band (e.g., a mmWave band) using long-term sensing. The medium access restrictions may include restrictions on certain transmission characteristics (e.g., maximum beamwidth, maximum transmit power, maximum transmit PSD, maximum duty cycle) and / or include LBT procedures.

[0061] Figure 3 A medium access scheme 300 with long-term sensing according to some aspects of the present disclosure is shown. Figure 3 , the x-axis represents time in some arbitrary units. Scheme 300 may be employed by wireless communication devices (e.g., BSs 105 and 205 and UEs 115 and 215) in a network (e.g., networks 100 and 200). Specifically, a wireless communication node or device may employ scheme 300 to perform medium access in a shared channel (e.g., a millimeter wave band of 10 GHz, 20 GHz, 30 GHz, 60 GHz) using long-term sensing, as shown in scheme 300. At a high level, a device may access a shared channel using a medium access protocol defined by a RAT (e.g., WiFi, NR-U) used by the device, and may utilize long-term channel sensing measurements to determine whether medium access restrictions are to be applied in addition to the medium access protocol.

[0062] In scheme 300, devices (e.g., BS 105 and / or 205 and UE 115 and / or 215) are configured with measurement opportunities 304 (e.g., at times T0 and T1). Measurement opportunities 304 can be periodic, for example, repeated at time intervals 302. Repeating time intervals 302 can have any suitable duration (e.g., approximately 1 millisecond (ms), 10 ms, 20 ms, 50 ms, or 100 ms or more). Each device can perform channel measurements during measurement opportunities 304. For example, during each measurement opportunity 304, the device can measure the channel energy in the shared channel (e.g., measurement value 310). For example, the device can calculate the received signal power at each measurement opportunity 304. The device can be configured with a front end at the device (e.g., Figure 5 RF unit 514, or Figure 6 RF unit 614) and / or a transceiver (e.g., Figure 5 transceiver 510, or Figure 6 The transceiver 610 of the present invention receives signals from one or more spatial directions via analog and / or digital beamforming. In some aspects, the device can measure the channel energy in all spatial directions, as shown in reference numeral 312. The device can collect statistics related to channel measurements 310 over a long period of time 301. The long period of time 301 can have any suitable duration (e.g., 0.1 seconds, 1 second, 2 seconds, 10 seconds, 60 seconds or longer). In some aspects, the long period of time 301 can include multiple measurement opportunities 304 (e.g., 5, 10, 20 or 30 or more). The device can determine a metric 320 based on the measurement values ​​310 collected over the long period of time 301. The device can determine whether the metric 320 meets one or more criteria for accessing the channel without medium access restrictions. For example, if the metric 320 is below a specific threshold, the device can access the channel without specific medium access restrictions. In other words, the medium access restrictions can include an energy detection threshold. If the metric 320 is above a specific threshold, the device applies medium access restrictions when accessing the channel. The metric 320 may be a particular statistical metric on the measurements 310 obtained during the long-term period 301. For example, the metric 320 may be an average channel energy measurement, a maximum channel energy measurement, a percentage of measurements above a threshold, a number of consecutive measurements above a threshold, and / or a variance of the measurements 310 in the long-term period 301.

[0063] In some aspects, the criteria for accessing the channel without medium access restrictions may include: making the most recent N channel measurement values ​​310 (in the most recent N consecutive measurement opportunities 304) below a specific threshold. For example, when each measurement value 310 of the most recent N channel measurement values ​​310 is below the threshold, the device can access the channel without medium access restrictions. On the other hand, if any of the most recent N channel measurements 310 is above the threshold, the device can apply medium access restrictions to channel access. N can be any suitable integer and can vary depending on the period of the measurement opportunity 304. For example, N can be 5, 10, 20, 30, 50 or more. The threshold for determining whether to apply medium access restrictions can be predetermined. In some other aspects, the access criteria for accessing the channel without medium access restrictions can be based on M measurement values ​​that meet a specific criterion (e.g., a specific threshold) among the most recent K measurement values ​​(e.g., in the most recent K measurement opportunities 304), where M and K are integers. For example, M can be 1, 2, 3, 4, 5, or more, and N can be 5, 10, 20, 30, 50, or more. In some aspects, the criteria and / or thresholds may be determined by the RAT that the device is using. In some aspects, the criteria and / or thresholds may be flexible or configurable (e.g., configured by the network or BS and may be based on network load and / or channel conditions). In some aspects, the criteria and / or thresholds may be determined by rules that specify medium access in a frequency band. In some aspects, medium access restrictions may also be specified by rules. Medium access restrictions may limit specific transmission characteristics (e.g., beamwidth, transmit power, transmit PSD, duty cycle) and / or LBT requirements prior to transmission, which will be described below. Figure 4B Further discussion in.

[0064] In some aspects, all cooperative devices, for example, operating under a certain RAT, may be configured by the network with measurement opportunities 304. Thus, all cooperative devices may remain silent (e.g., no transmission) during the measurement opportunities 304. This may allow other cooperative devices to perform channel measurements without interference from another cooperative device. During the measurement opportunities used to determine the long-term sensing metrics 320, the cooperative devices may also perform channel measurements. If there are non-cooperative devices (which may be BSs 105 or 205 or UEs 115 or 215) in the vicinity of the network, the non-cooperative devices may transmit at a certain point in time. Thus, the cooperative devices may detect the presence of non-cooperative devices through measurement values ​​310 (e.g., one or more measurement values ​​310 within the long-term period 301 may exceed a threshold). Thus, the cooperative devices may detect whether there are any non-cooperative nodes nearby based on the long-term sensing measurements 310 and / or the long-term sensing metrics 320.

[0065] exist Figure 3In the example shown, the network may be an isolated deployment. In other words, all devices in the network may be cooperating devices. Isolated deployments may be common in mmWave networks because mmWave communications may have a shorter range or range, so multiple localized deployments may be created within a geographic area. Thus, each device may have long-term sensing metrics 320 that meet the criteria for accessing the channel without additional medium access restrictions.

[0066] In some aspects, the cooperating devices may access or share the shared channel based on a medium access procedure or protocol defined by the RAT in use. For example, a cooperating device (e.g., BS 105 or 205 or UE 115 or 215) may win one or more COTs 306 in a shared channel based on a medium access protocol defined by the RAT, and may communicate (e.g., PDSCH signals, PDCCH signals, PUSCH signals, and / or PUCCH signals) with one or more other cooperating devices during the COT 306). In some aspects, the medium access protocol defined by the RAT may utilize a synchronous access scheme (e.g., a frame-based device (FBE) scheme) or an asynchronous access scheme (e.g., a load-based device (LBE) scheme). In some aspects, the medium access protocol defined by the RAT may utilize a contention scheme based on energy detection or a contention scheme based on signal detection. The medium access protocol may utilize various reserved signals (e.g., a predetermined preamble sequence, a request to send (RTS), a clear to send (CTS), CTS-self, and / or a COT indication signal) to exchange contention schemes. In some aspects, the medium access protocol defined by the RAT may define certain contention parameters (e.g., maximum occupancy time and / or contention window size). In some aspects, the medium access protocol defined by the RAT may include interference management, e.g., limiting certain transmission parameters between cooperating nodes sharing access in a channel.

[0067] Figure 4A About Figure 4B It is shown that medium access with long term sensing is discussed when long term sensing measurements fail to satisfy one or more criteria for access without medium access restrictions. Figure 4A A medium access scheme 400 with long-term sensing according to some aspects of the present disclosure is shown. Figure 4A, the x-axis represents time in some arbitrary units. Scheme 400 may be employed by wireless communication devices (e.g., BSs 105 and 205, and UEs 115 and 215) in a network (e.g., networks 100 and 200). Specifically, a wireless communication node or device may employ scheme 400 to perform medium access in a shared channel (e.g., in millimeter wave bands of 10 GHz, 20 GHz, 30 GHz, 60 GHz) using long-term sensing as shown in scheme 400. Scheme 400 is substantially similar to scheme 300, and provides a detailed view of medium access in the presence of medium access restrictions when long-term sensing measurements fail to meet one or more criteria for access without medium access restrictions. For simplicity, Figure 4A Can be reused with Figure 3 Same reference numerals.

[0068] Similar to the scheme 300, the monitoring device (e.g., BS 105 and / or 205 and UE 115 and / or 215) may determine channel measurements 410 during each measurement opportunity 304 over the long-term period 301. The channel measurements may be determined in various spatial directions (e.g., Figure 3 The monitoring device can measure channel measurements 410 in all directions as shown in 312 of FIG. 301 based on the channel measurements 410 collected over the long term period 301 (e.g., using the channel measurements 410 as described above with reference to FIG. 302 ). Figure 3 Long term sensing metrics 412 are determined using a similar mechanism discussed in scheme 300 . Figure 4A In the example shown, there may be other nearby non-cooperative devices (e.g., of another RAT or the same RAT) transmitting in the network. Therefore, at T1, the monitoring device may detect that one or more channel measurements 410 exceed a threshold value in the most recent N measurements. Therefore, the monitoring device knows that it is not operating in an isolated deployment. Therefore, the monitoring device may access the channel by applying additional medium access restrictions, which may be specified by rules. Alternatively, at time T1, the monitoring device may detect that M of the K measurements do not meet a certain criterion (e.g., a certain threshold value).

[0069] As shown, when the monitoring device accesses the channel to acquire the COT 306, the monitoring device may apply medium access restrictions 420. For example, the medium access restrictions 420 may include: Figure 4B Although Figure 4A 4. The medium access restrictions 420 are shown to be applied when the COT 306 is captured. The medium access restrictions 420 may be applied to transmissions within the COT 306. For example, the medium access restrictions 420 may include restrictions on one or more transmission parameters, such as Figure 4B as shown in .

[0070] Figure 4B 4 shows a medium access restriction 420 according to some aspects of the present disclosure. For example, when the long-term sensing measurement value 410 fails to meet a certain condition for accessing the channel without medium access restriction, the wireless communication devices (e.g., BSs 105 and 205 and UEs 115 and 215) in the network (e.g., networks 100 and 200) can adopt the medium access restriction 420, as described above in Figure 3 and discussed in 4.

[0071] The medium access restriction 420 may include one or more of the following: a transmit beamwidth restriction 422, a transmit (Tx) power restriction 424, a transmit (Tx) PSD restriction 426, a transmit duty cycle restriction 428, or an LBT process 430. The transmit beamwidth restriction 422 may include a beamwidth threshold. For example, a device accessing a channel having the medium access restriction 420 may transmit using a transmit beam (e.g., transmit beams 202a and / or 202b) having a beamwidth that does not exceed the beamwidth threshold. In some cases, the beamwidth of a transmit beam may refer to the angle at which most of the power (i.e., peak power) is radiated. For example, the device may have stored in a memory (e.g., Figure 5 Memory 504, or Figure 6 The device may select one or more transmission configuration parameters from the table so that the generated transmit beam may have a beam width that satisfies the beam width threshold. In some cases, the beam width threshold may be a maximum instantaneous beam width threshold for limiting the instantaneous beam width of the transmission at each moment. In some other cases, the beam width threshold may be a maximum average beam width threshold for limiting the average beam width over the duration of the transmission.

[0072] The transmit power limit 424 may include a transmit power threshold. For example, a device accessing a channel having a medium access limit 420 may transmit using a transmit power that does not exceed the transmit power threshold. For example, a device may store in a memory (e.g., Figure 5 Memory 504 or Figure 6 The device may have a specific pre-configured transmission data table related to transmission configuration parameters and corresponding output transmit powers at a memory 604 of the device. The device may select one or more transmission configuration parameters from the table so that the generated transmission may have a transmit power that satisfies the transmit power threshold. In some cases, the transmit power threshold may be a maximum instantaneous transmit power threshold for limiting the instantaneous transmit power of the transmission at each moment. In some other cases, the transmit power threshold may be a maximum average transmit power for limiting the average transmit power over the duration of the transmission.

[0073] The transmit PSD limit 426 may include a transmit PSD threshold. For example, a device accessing a channel with medium access restrictions 420 may transmit using a greater transmit PSD that does not exceed the transmit PSD threshold. For example, the device may determine a transmit power for a particular transmission signal bandwidth occupancy such that a generated transmission may have a transmit PSD that satisfies the transmit PSD threshold. As discussed above, the device may select one or more transmission configuration parameters for the determined transmit power.

[0074] The transmission duty cycle limit 428 may include a duty cycle threshold. For example, a device accessing a channel with medium access restrictions 420 may transmit based on a duty cycle that does not exceed the duty cycle threshold. For example, the device may determine a transmission duration for a transmission and a transmission gap between transmissions so that the transmission duty cycle may satisfy the duty cycle threshold. In other words, once a device obtains access to a channel, the medium access restrictions 420 may include a channel occupancy time (COT) limit.

[0075] The medium access restriction 420 with LBT process 430 can restrict the access of the device to the channel based on the LBT result. For example, the device can perform LBT process 430 in the channel to compete for COT 306. The LBT process 430 can be CAT2, CAT3 or CAT4 LBT. In some cases, the LBT process 430 can be LBT based on energy detection. In other words, the medium access restriction 420 can include LBT requirements (e.g., whether LBT can be omitted before transmission or the LBT mode used to access the channel) and / or an energy detection threshold (EDT) used for LBT.

[0076] In some aspects, the medium access restrictions 420 may include all of the restrictions 422-428 and the LBT process 430. In some aspects, the medium access restrictions 420 may include the LBT process 430. In some aspects, the medium access restrictions 420 may include one of the restrictions 422-428. In some aspects, the medium access restrictions 420 may include two of the restrictions 422-428. In general, the medium access restrictions 420 may include any suitable combination of restrictions 422-428 and the LBT process 430, and may vary according to the rules that specify the channel in use. In other words, in the scheme 400, the medium access restrictions may refer to specific LBT requirements (e.g., whether LBT can be omitted before transmission, or the LBT mode for accessing the channel), specific energy detection threshold (EDT) requirements for LBT, channel occupancy time (COT) restrictions once access to the channel is obtained, or any combination thereof.

[0077] Figure 55 is a block diagram of an exemplary UE 500 according to some aspects of the present disclosure. UE 500 may be the Figure 1 UE 115 discussed in, or above in Figure 2 215 discussed in . As shown, UE 500 may include a processor 502, a memory 504, a media access module 508, a transceiver 510 including a modem subsystem 512 and a radio frequency (RF) unit 514, and one or more antennas 516. These elements may be coupled to each other. The term "coupled" may refer to being directly or indirectly coupled or connected to one or more intermediate elements. For example, these elements may communicate with each other directly or indirectly (e.g., via one or more buses).

[0078] The processor 502 may include a central processing unit (CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a controller, a field programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 502 may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, a combination of one or more microprocessors and a DSP core, or any other such configuration.

[0079] The memory 504 may include cache memory (e.g., cache memory of the processor 502), random access memory (RAM), magnetoresistive RAM (MRAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, a solid-state memory device, a hard drive, other forms of volatile and non-volatile memory, or a combination of different types of memory. In one aspect, the memory 504 includes a non-transitory computer-readable medium. The memory 504 may store or have recorded thereon instructions 506. The instructions 506 may include instructions that, when executed by the processor 502, cause the processor 502 to perform operations in conjunction with aspects of the present disclosure (e.g., Figure 1-Figure 3 , Figure 4A-4B and Figure 7-Figure 8Instructions 506 may also be referred to as program code. The program code may be used to cause the wireless communication device to perform the operations, for example, by causing one or more processors (e.g., processor 502) to control or command the wireless communication device to do so. The terms "instructions" and "code" should be broadly interpreted to include any type of computer-readable statements. For example, the terms "instructions" and "code" may refer to one or more programs, routines, subroutines, functions, processes, etc. "Instructions" and "code" may include a single computer-readable statement or a plurality of computer-readable statements.

[0080] The media access module 508 may be implemented via hardware, software, or a combination thereof. For example, the media access module 508 may be implemented as a processor, circuit, and / or instructions 506 stored in the memory 504 and executed by the processor 502. In some examples, the media access module 508 may be integrated within the modem subsystem 512. For example, the media access module 508 may be implemented by a combination of software components (e.g., executed by a DSP or general purpose processor) and hardware components (e.g., logic gates and circuits) within the modem subsystem 512.

[0081] The media access module 508 may be used in various aspects of the present disclosure, for example, Figure 1-3 , Figure 4A-4B and Figure 7-8 For example, the medium access module 508 is configured to: for example, receive a measurement configuration indicating multiple measurement opportunities spaced apart in time from a BS (e.g., BS 105 and / or 205), perform channel measurements during multiple measurement opportunities in a shared radio frequency band, and determine whether the channel measurements meet a criterion (e.g., a specific threshold) for accessing the shared radio frequency band without medium access restrictions. In some aspects, the medium access module 508 may perform channel measurements in all spatial directions. In some aspects, the medium access restrictions may be part of the provisions for accessing the shared radio frequency band. In some aspects, the medium access restrictions may limit specific transmission characteristics, such as transmit beamwidth, transmit power, transmit PSD and / or transmit duty cycle, and / or utilization of LBT prior to transmission.

[0082] In some aspects, the medium access module 508 is configured to send communication signals in the shared radio frequency band without medium access restrictions in response to determining that the channel measurement meets criteria for accessing the shared radio frequency band without medium access restrictions. In some aspects, the medium access module 508 may access the shared radio frequency band based on a medium access protocol defined by a radio access technology (RAT) in use.

[0083] In some aspects, the medium access module 508 is configured to, in response to determining that the channel measurement fails to meet the criteria for accessing the shared radio frequency band without the medium access restriction, transmit the communication signal in the shared radio frequency band with the medium access restriction. In some aspects, the medium access module 508 may configure the transceiver 510 to transmit the first communication signal using a transmit beam having a beam width that satisfies a beam width threshold based on the medium access restriction. In some aspects, the medium access module 508 may configure the transceiver 510 to transmit the first communication signal using a transmit power that satisfies a transmit power threshold based on the medium access restriction. In some aspects, the medium access module 508 may configure the transceiver 510 to transmit the first communication signal with a transmit PSD that satisfies a transmit PSD threshold based on the medium access restriction. In some aspects, the medium access module 508 may configure the transceiver 510 to transmit the first communication signal with a transmit duration that satisfies a duty cycle threshold based on the medium access restriction. In some aspects, the medium access module 508 may configure the transceiver 510 to perform LBT prior to transmitting the first communication signal based on the medium access restriction. In some aspects, the medium access module 508 may configure the transceiver 510 so that one or more of a beam width threshold, a transmit power threshold, a transmit PSD threshold, a transmit duty cycle threshold, and / or a utilization of LBT are met for transmission of the first communication signal. Mechanisms for medium access with long-term channel sensing are described in greater detail herein.

[0084] As shown, the transceiver 510 may include a modem subsystem 512 and an RF unit 514. The transceiver 510 may be configured to communicate bidirectionally with other devices (such as BS 105). The modem subsystem 512 may be configured to modulate and / or encode data from the memory 504 and / or the medium access module 508 according to a modulation and coding scheme (MCS) (e.g., a low-density parity check (LDPC) coding scheme, a turbo coding scheme, a convolutional coding scheme, a polarization coding scheme, a digital beamforming scheme, etc.). The RF unit 514 may be configured to process (e.g., perform analog-to-digital conversion or digital-to-analog conversion, etc.) the modulated / encoded data (e.g., PUSCH, PUCCH, channel reservation signal) from the modem subsystem 512 (on outbound transmission) or the modulated / encoded data of the transmission originating from another source (such as UE 115 or BS 105). The RF unit 514 may also be configured to perform analog beamforming in conjunction with digital beamforming. Although shown as being integrated together in the transceiver 510, the modem subsystem 512 and the RF unit 514 may be separate devices that are coupled together at the UE 115 to enable the UE 115 to communicate with other devices.

[0085] The RF unit 514 can provide modulated and / or processed data, such as data packets (or more generally, data messages that can contain one or more data packets and other information) to the antenna 516 for transmission to one or more other devices. The antenna 516 can also receive data messages sent from other devices. The antenna 516 can provide the received data message for processing and / or demodulation at the transceiver 510. The transceiver 510 can provide the demodulated and decoded data (e.g., RRC configuration, PDSCH, PDCCH, measurement configuration, channel reservation signal) to the medium access module 508 for processing. The antenna 516 can include multiple antennas with similar or different designs to maintain multiple transmission links. The RF unit 514 can configure the antenna 516.

[0086] In some aspects, the processor 502 is configured to coordinate with the medium access module 508 to perform channel measurements in the shared radio frequency band during a plurality of measurement opportunities spaced apart in time, and to determine whether the channel measurements meet criteria for accessing the shared radio frequency band without medium access restrictions. The channel measurements may be performed in all spatial directions. The transceiver 510 is coupled to the processor 502 and is configured to coordinate with the medium access module 508 to send a first communication signal in the shared radio frequency band without medium access restrictions in response to determining that the channel measurements meet the criteria. The first communication signal may be sent in a first spatial direction of the plurality of spatial directions.

[0087] In one aspect, the UE 500 may include multiple transceivers 510 that implement different RATs (e.g., NR and LTE). In one aspect, the UE 500 may include a single transceiver 510 that implements multiple RATs (e.g., NR and LTE). In one aspect, the transceiver 510 may include various components, where different combinations of the multiple components may implement different RATs.

[0088] Figure 6 600 according to some aspects of the present disclosure. BS 600 may be as described above in Figure 1 105 in the network 100 discussed in the figure. As shown, BS 600 may include a processor 602, a memory 604, a media access module 608, a transceiver 610 including a modem subsystem 612 and an RF unit 614, and one or more antennas 616. These elements may be coupled to each other. The term "coupled" may refer to being directly or indirectly coupled or connected to one or more intermediate elements. For example, these elements may communicate with each other directly or indirectly, for example, via one or more buses.

[0089] The processor 602 may have various characteristics as a particular type of processor. For example, these may include a CPU, a DSP, an ASIC, a controller, an FPGA device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 602 may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in combination with a DSP core, or any other such configuration.

[0090] The memory 604 may include cache memory (e.g., cache memory of the processor 602), RAM, MRAM, ROM, PROM, EPROM, EEPROM, flash memory, solid-state memory devices, one or more hard disk drives, memristor-based arrays, other forms of volatile and nonvolatile memory, or a combination of different types of memory. In some aspects, the memory 604 may include non-transitory computer-readable media. The memory 604 may store instructions 606. The instructions 606 may include instructions that, when executed by the processor 602, cause the processor 602 to perform the operations described herein (e.g., Figure 1-Figure 3 , Figure 4A-4B and Figure 7-Figure 8 Instructions 606 may also be referred to as code, which may be broadly interpreted as including the above-mentioned instructions. Figure 5 Any type of computer-readable statement discussed.

[0091] The media access module 608 may be implemented via hardware, software, or a combination thereof. For example, the media access module 608 may be implemented as a processor, circuit, and / or instructions 606 stored in the memory 604 and executed by the processor 602. In some examples, the media access module 608 may be integrated within the modem subsystem 512. For example, the sidelink communication module 508 may be implemented by a combination of software components (e.g., executed by a DSP or general purpose processor) and hardware components (e.g., logic gates and circuits) within the modem subsystem 612.

[0092] The media access module 608 may be used in various aspects of the present disclosure, for example, Figure 1-Figure 3 , Figure 4A-4B and Figure 7-Figure 8For example, the medium access module 508 is configured to determine a plurality of measurement opportunities spaced apart in time, perform channel measurements during the plurality of measurement opportunities in a shared radio frequency band, for example, send a measurement configuration indicating a plurality of measurement opportunities to a UE (e.g., UE 115, 215, and / or 500), and determine whether the channel measurements meet criteria (e.g., a specific threshold) for accessing the shared radio frequency band without medium access restrictions. In some aspects, the medium access module 508 may perform channel measurements in all spatial directions. In some aspects, the medium access restrictions may be part of the rules for accessing the shared radio frequency band. In some aspects, the medium access restrictions may limit specific transmission characteristics, such as transmit beamwidth, transmit power, transmit PSD, transmit duty cycle, and / or utilization of LBT prior to transmission.

[0093] In some aspects, the medium access module 608 is configured to: in response to determining that the channel measurement meets the criteria for accessing the shared radio frequency band without medium access restrictions, send the communication signal in the shared radio frequency band without medium access restrictions. In some aspects, the medium access module 608 can access the shared radio frequency band based on a medium access protocol as defined by the radio access technology (RAT) in use.

[0094] In some aspects, the medium access module 608 is configured to transmit a communication signal in a shared radio frequency band with a medium access restriction in response to determining that the channel measurement fails to meet the criteria for accessing the shared radio frequency band without the medium access restriction. In some aspects, the medium access module 608 may configure the transceiver 610 to transmit the first communication signal using a transmit beam having a beam width that meets a beam width threshold based on the medium access restriction. In some aspects, the medium access module 608 may configure the transceiver 610 to transmit the first communication signal using a transmit power that meets a transmit power threshold based on the medium access restriction. In some aspects, the medium access module 608 may configure the transceiver 610 to transmit the first communication signal with a transmit PSD that meets a transmit PSD threshold based on the medium access restriction. In some aspects, the medium access module 608 may configure the transceiver 610 to transmit the first communication signal with a transmit duration that meets a duty cycle threshold based on the medium access restriction. In some aspects, the medium access module 608 may configure the transceiver 610 to perform LBT prior to transmitting the first communication signal based on the medium access restriction. In some aspects, the medium access module 608 may configure the transceiver 610 so that one or more of a beam width threshold, a transmit power threshold, a transmit PSD threshold, a transmit duty cycle threshold, and / or a utilization of LBT is met for transmission of the first communication signal. Mechanisms for medium access with long-term channel sensing are described in greater detail herein.

[0095] As shown, the transceiver 610 may include a modem subsystem 612 and an RF unit 614. The transceiver 610 may be configured to communicate bidirectionally with other devices (such as UE 115 and / or UE 500 and / or another core network unit). The modem subsystem 612 may be configured to modulate and / or encode data according to an MCS (e.g., an LDPC coding scheme, a turbo coding scheme, a convolutional coding scheme, a polarization coding scheme, a digital beamforming scheme, etc.). The RF unit 614 may be configured to process (e.g., perform analog-to-digital conversion or digital-to-analog conversion, etc.) modulated / encoded data (e.g., RRC configuration, PDSCH, PDCCH, measurement configuration, channel reservation signal) from the modem subsystem 612 (on outbound transmission) or modulated / encoded data transmitted from another source (such as UE 115 and / or UE 500). The RF unit 614 may also be configured to perform analog beamforming in conjunction with digital beamforming. Although shown as being integrated together in transceiver 610, modem subsystem 612 and / or RF unit 614 may be separate devices that are coupled together at BS 105 to enable BS 105 to communicate with other devices.

[0096] The RF unit 614 may provide modulated and / or processed data, e.g., data packets (or more generally, data messages that may contain one or more data packets and other information), to the antenna 616 for transmission to one or more other devices. This may include, for example, the transmission of information in accordance with aspects of the present disclosure to complete attachment to a network and communication with a resident UE 115 or 500. The antenna 616 may also receive data messages sent from other devices and provide the received data messages for processing and / or demodulation at the transceiver 610. The transceiver 610 may provide the demodulated and decoded data (e.g., PUSCH, PUCCH, channel reservation signal) to the medium access module 608 for processing. The antenna 616 may include multiple antennas of similar or different designs in order to maintain multiple transmission links.

[0097] In some aspects, the processor 602 is configured to coordinate with the medium access module 608 to perform channel measurements in the shared radio frequency band during a plurality of measurement opportunities spaced apart in time, and to determine whether the channel measurements meet criteria for accessing the shared radio frequency band without medium access restrictions. The channel measurements may be performed in all spatial directions. The transceiver 610 is coupled to the processor 602 and is configured to coordinate with the medium access module 608 to send a first communication signal in the shared radio frequency band without medium access restrictions in response to determining that the channel measurements meet the criteria. The first communication signal may be sent in a first spatial direction of the plurality of spatial directions.

[0098] In one aspect, the BS 600 may include multiple transceivers 610 that implement different RATs (e.g., NR and LTE). In one aspect, the BS 600 may include a single transceiver 610 that implements multiple RATs (e.g., NR and LTE). In one aspect, the transceiver 610 may include various components, where different combinations of the multiple components may implement different RATs.

[0099] Figure 7 is a flow chart of a medium access method 700 with long-term sensing according to some aspects of the present disclosure. Aspects of method 700 may be performed by a computing device (e.g., a processor, processing circuitry, and / or other suitable components) of a wireless communication device or other suitable means for performing these steps. For example, a wireless communication device such as UE 115, 215, and / or 500 may employ one or more components (e.g., a processor 502, a memory 504, a medium access module 508, a transceiver 510, a modem 512, and one or more antennas 516) to perform the steps of method 700. Alternatively, a wireless communication device such as BS 105, 205, and / or 600 may employ one or more components (e.g., a processor 602, a memory 604, a medium access module 608, a transceiver 610, a modem 612, and one or more antennas 616) to perform the steps of method 700. Method 700 may be implemented as described above with reference to the respective embodiments. Figure 3 and Figure 4A The schemes 300 and 400 discussed above refer to Figure 4B A similar mechanism is discussed in the medium access restriction 420. As shown, the method 700 includes a plurality of enumerated steps, but aspects of the method 700 may include additional steps before, after, and between the enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0100] At block 710, a wireless communication device (e.g., BS 105, 205, or 600 or UE 115, 215, or 500) initializes a medium access process in compliance with a medium access restriction of a rule for a channel (e.g., in a mmWave frequency band). In other words, the wireless communication device may begin by performing medium access in a channel that complies with the medium access restriction defined by the rule. The medium access restriction may be similar to the medium access restriction 420. For example, based on the rule, the medium access restriction may limit one or more of: a transmit PSD limit 426), a transmit duty cycle (e.g., a transmit duty cycle limit 428), and / or a utilization of LBT (e.g., an LBT process 430). In some cases, the wireless communication device may employ one or more components (e.g., processor 502 or 602, medium access module 508 or 608, transceiver 510 or 610, modem 512 or 612, and / or one or more antennas 516 or 616) to initialize a medium access process (e.g., by configuring transmission parameters and / or an LBT process for accessing a channel in accordance with medium access restrictions).

[0101] At box 720, the wireless communication device performs channel measurements in one or more spatial directions. For example, the wireless communication device is configured with periodic measurement opportunities (e.g., measurement opportunities 304). The wireless communication device can determine channel energy measurements (e.g., channel measurements 310 and 410) at each measurement opportunity. The wireless communication device can also determine long-term sensing metrics (e.g., metrics 320 and / or 412). In some cases, the wireless communication device can use one or more components (e.g., processor 502 or 602, medium access module 508 or 608, transceiver 510 or 610, modem 512 or 612, and / or one or more antennas 516 or 616) (e.g., by receiving a signal from the channel at each measurement opportunity, calculating the received signal power of the received signal, saving the history of the received signal power in a memory, and determining the long-term sensing metric based on the history of the received signal power) to perform channel measurements. In some cases, channel measurements can be performed in spatial directions.

[0102] At block 730, the wireless communication device determines whether the wireless communication device is operating in an isolated deployment (e.g., in the absence of non-cooperative nodes in the vicinity). For example, the wireless communication device may employ one or more components (e.g., processor 502 or 602, medium access module 508 or 608, transceiver 510 or 610, modem 512 or 612, and / or one or more antennas 516 or 616) to determine whether the long-term sensing metric meets a particular threshold. The wireless communication device may determine whether each of the most recent N measurements measured in the measurement opportunity meets the threshold. If the wireless communication device determines that all N measurements are below the threshold, there are no non-cooperative nodes in the vicinity, so the wireless communication device is operating in an isolated deployment and may proceed to block 750. In some other cases, the wireless communication device may determine whether the wireless communication device is operating in an isolated deployment based on whether M of the most recent K measurements measured in the measurement opportunity meet a particular criterion (e.g., a particular threshold).

[0103] At block 750, the wireless communication device accesses the medium based on the RAT in use without regulatory-imposed medium access restrictions. For example, the RAT may define a medium access protocol (e.g., employing a specific contention scheme and / or having contention parameters for intra-technology access), as described above with reference to Figure 3 As discussed. In some cases, the wireless communication device may employ one or more components (e.g., processor 502 or 602, medium access module 508 or 608, transceiver 510 or 610, modem 512 or 612, and / or one or more antennas 516 or 616) to perform medium access based on the medium access protocol defined by the RAT. After performing medium access, the wireless communication device (e.g., at the next measurement opportunity) may return to block 720 and perform another channel measurement. In some cases, the wireless communication device may win one or more COTs (e.g., COT 306) from intra-technology competition. In some cases, the wireless communication device may not win any COTs from intra-technology competition.

[0104] Returning to block 730, if the wireless communication device determines that it is not operating in an isolated deployment (e.g., the long-term sensing metric fails to meet a threshold), the wireless communication device may proceed to block 740. At step 740, the wireless communication device accesses the medium subject to the specified medium access restrictions. In addition to the medium access protocol defined by the RAT, the wireless communication device may also apply medium access restrictions. In some cases, the wireless communication device may employ one or more components (e.g., the processor 502 or 602, the medium access module 508 or 608, the transceiver 510 or 610, the modem 512 or 612, and / or one or more antennas 516 or 616) to perform medium access subject to medium access restrictions (e.g., by configuring the transmit beamwidth to meet a beamwidth threshold, configuring the transmit power to meet a transmit power threshold, configuring the transmit PSD to meet a transmit PSD threshold, configuring the transmission duration and the transmission interval to meet a duty cycle threshold, and / or performing LBT before accessing the channel as defined by the access rule).

[0105] After performing medium access, the wireless communication device may return to block 720 (e.g., at the next measurement opportunity) and perform another channel measurement. In some cases, the wireless communication device may win one or more COTs (e.g., COT 306) from intra-technology contention and inter-technology contention. In some cases, the wireless communication device may not win any COTs from intra-technology contention and inter-technology contention.

[0106] The criterion of long-term sensing having each of the most recent N measurements and / or M of the K measurements satisfy a threshold may allow the wireless communication device to quickly detect a non-isolated deployment (e.g., when there is another non-cooperative node deployed nearby), whereas detection of an isolated deployment may take time (e.g., after 2, 3, 4, or more long-term periods 301). In addition, the rate at which new nodes can be discovered may be determined by the periodicity or repetitive time interval of the measurement opportunities (e.g., time interval 302).

[0107] Figure 8800 is a flowchart of a wireless communication method 800 according to some aspects of the present disclosure. Various aspects of method 800 may be performed by a computing device (e.g., a processor, a processing circuit, and / or other suitable components) of a wireless communication device or other suitable means for performing these steps. For example, a wireless communication device (e.g., UE 115, 215, and / or 500) may employ one or more components (e.g., a processor 502, a memory 504, a medium access module 508, a transceiver 510, a modem 512, and one or more antennas 516) to perform the steps of method 800. Alternatively, a wireless communication device (e.g., BS 105, 205, and / or 600) may employ one or more components (e.g., a processor 602, a memory 604, a medium access module 608, a transceiver 610, a modem 612, and one or more antennas 616) to perform the steps of method 800. Method 800 may be implemented as described above with reference to the respective embodiments. Figure 3 and 4A The schemes 300 and 400 discussed above refer to Figure 4B The medium access restrictions 420 discussed above, and the Figure 7 A similar mechanism is discussed in method 700. As shown, method 800 includes a plurality of enumerated steps, but aspects of method 800 may include additional steps before, after, and between the enumerated steps. In some aspects, one or more of the enumerated steps may be omitted or performed in a different order.

[0108] At box 810, a wireless communication device (e.g., BS105, 205 or 600 or UE 115, 215 or 500) performs channel measurements in a shared radio frequency band (e.g., a millimeter wave band or a 60 GHz unlicensed band) during multiple measurement opportunities (e.g., measurement opportunities 304) spaced apart in time. Channel measurements are performed based on multiple spatial directions. In some aspects, channel measurements may be performed based on omnidirectional channel measurements (e.g., including all spatial directions). In some cases, the wireless communication device may employ one or more components (e.g., processor 502 or 602, medium access module 508 or 608, transceiver 510 or 610, modem 512 or 612, and / or one or more antennas 516 or 616) (e.g., by receiving a signal from the channel at each measurement opportunity, calculating the received signal power of the received signal, and storing the history of the received signal power in a memory) to perform channel measurements.

[0109] At block 820, the wireless communication device determines whether the channel measurements meet criteria for accessing the shared radio frequency band without medium access restrictions (e.g., medium access restrictions 420). In some aspects, the medium access restrictions may refer to specific LBT requirements (e.g., whether LBT can be omitted prior to transmission), specific energy detection threshold (EDT) requirements to be used for LBT, channel occupancy time (COT) limits once access to the channel is obtained, or any combination thereof. In some cases, the wireless communication device may employ one or more components, such as a processor 502 or 602, a medium access module 508 or 608, a transceiver 510 or 610, a modem 512 or 612, and / or one or more antennas 516 or 616, to determine whether the channel measurements meet criteria for accessing the shared radio frequency band without medium access restrictions.

[0110] In some aspects, determining whether the channel measurement satisfies the criteria includes determining whether each measurement value determined from a set of consecutive measurement opportunities in a plurality of measurement opportunities satisfies a threshold. In some aspects, determining whether the channel measurement satisfies the criteria includes determining whether a predetermined number of channel measurements determined from a set of measurement opportunities in a plurality of measurement opportunities satisfies the criteria.

[0111] At block 830 , the wireless communication device transmits a first communication signal in a shared radio frequency band in a first spatial direction without medium access restrictions in response to determining that the channel measurement satisfies the criteria, the plurality of spatial directions including the first spatial direction.

[0112] In some aspects, the medium access restriction includes a transmit beamwidth threshold (e.g., beamwidth limit 422), a transmit power threshold (e.g., transmit power limit 424), a transmit PSD threshold (e.g., transmit PSD limit 426), a transmit duty cycle threshold (e.g., transmit duty cycle limit 428), and / or an LBT process (e.g., LBT process 430), as described above with reference to Figure 4B discussed.

[0113] In some aspects, the medium access restriction includes a beamwidth threshold (eg, beamwidth restriction 422), and sending the first communication signal at block 830 includes sending the first communication signal using a transmit beam having a beamwidth that does not satisfy the beamwidth threshold.

[0114] In some aspects, the medium access restriction includes a transmit power threshold (eg, transmit power limit 424), and sending the first communication signal at block 830 includes sending the first communication signal using a transmit power that does not satisfy the transmit power threshold.

[0115] In some aspects, the medium access restriction includes a transmit PSD threshold (eg, transmit PSD limit 426), and sending the first communication signal at block 830 includes sending the first communication signal having a transmit PSD that does not satisfy the PSD threshold.

[0116] In some aspects, the medium access restriction includes a duty cycle threshold (eg, the transmit duty cycle limit 428), and sending the first communication signal at block 830 includes sending the first communication signal based on a duty cycle that does not satisfy the duty cycle threshold.

[0117] In some aspects, the medium access restriction includes LBT (eg, LBT process 430), and sending the first communication signal at block 830 includes sending the first communication signal without performing LBT.

[0118] In some aspects, the wireless communication device may also perform a second channel measurement in the shared radio frequency band during a second plurality of measurement opportunities separated in time. Performing the second channel measurement may be based on multiple spatial directions. In response to determining that the second channel measurement does not meet the criteria for accessing the shared radio frequency band without medium access restrictions, the wireless communication device may also send a second communication signal in the shared radio frequency band in the second spatial direction with medium access restrictions. In some aspects, sending the second communication signal may include: based on the medium access restrictions, using a transmit beam with a beam width that meets a beam width threshold. In some aspects, sending the second communication signal may include: based on the medium access restrictions, using a transmit power that meets a transmit power threshold. In some aspects, the second communication signal may have a transmit PSD that meets a transmit PSD threshold based on the medium access restrictions. In some aspects, sending the second communication signal may be based on a duty cycle that meets a duty cycle threshold based on the medium access restrictions. In some aspects, sending the second communication signal may include: based on the medium access restrictions, performing LBT before sending the second communication signal.

[0119] Other aspects of the present disclosure include a wireless communication method. The wireless communication method includes performing, by a wireless communication device, channel measurements in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the performing channel measurements being based on a plurality of spatial directions; determining, by the wireless communication device, whether the channel measurements satisfy a criterion for accessing the shared radio frequency band without medium access restrictions; and, in response to determining that the channel measurements satisfy the criterion, transmitting, by the wireless communication device, a first communication signal in the shared radio frequency band in a first spatial direction without medium access restrictions, the plurality of spatial directions including the first spatial direction.

[0120] The method may also include one or more of the following features. For example, the method may include: wherein determining whether the channel measurement meets the standard includes determining whether each measurement determined according to a set of consecutive measurement opportunities in a plurality of measurement opportunities meets the standard. Determining whether the channel measurement meets the standard includes determining whether each measurement value determined according to a set of consecutive measurement opportunities in a plurality of measurement opportunities meets a threshold. Determining whether the channel measurement meets the standard includes determining whether a predetermined number of channel measurements determined according to a set of measurement opportunities in a plurality of measurement opportunities meet the standard. The medium access restriction includes a beam width threshold, and wherein sending the first communication signal includes sending the first communication signal by the wireless communication device using a transmit beam with a beam width that does not meet the beam width threshold. The medium access restriction includes a transmit power threshold, and wherein sending the first communication signal includes sending the first communication signal by the wireless communication device using a transmit power that does not meet the transmit power threshold. The medium access restriction includes a transmit power spectral density (PSD) threshold, and wherein sending the first communication signal includes sending the first communication signal by the wireless communication device having a transmit PSD that does not meet the transmit PSD threshold. The medium access restriction includes a duty cycle threshold, and wherein sending the first communication signal includes: sending the first communication signal by the wireless communication device based on a duty cycle that does not meet the duty cycle threshold. The medium access restriction includes listen before talk (LBT), and wherein sending the first communication signal includes sending the first communication signal without performing LBT. The method may also include: performing a second channel measurement in the shared radio frequency band during a second plurality of measurement opportunities spaced apart in time by the wireless communication device, the performing the second channel measurement being based on a plurality of spatial directions; and, in response to determining that the second channel measurement fails to meet a criterion for accessing the shared radio frequency band without the medium access restriction, sending the second communication signal in the shared radio frequency band in a second spatial direction with the medium access restriction by the wireless communication device. The sending the second communication signal includes: sending the second communication signal by the wireless communication device, based on the medium access restriction, using a transmit beam having a beam width that meets the beam width threshold. The sending the second communication signal includes: sending the second communication signal by the wireless communication device, based on the medium access restriction, using a transmit power that meets the transmit power threshold. The sending of the second communication signal includes: the wireless communication device, based on the medium access restriction, sends the second communication signal having a transmit power spectral density (PSD) threshold value. The sending of the second communication signal includes: the wireless communication device, based on the medium access restriction, sends the second communication signal based on a duty cycle that satisfies the duty cycle threshold value. The sending of the second communication signal includes: the wireless communication device, based on the medium access restriction, performs a listen before talk (LBT) process before sending the second communication signal. The shared radio frequency band is a millimeter wave (mmWav) unlicensed band.

[0121] Other aspects of the present disclosure include a wireless communication device. The wireless communication device includes a processor and a transceiver, the processor being configured to: perform channel measurements in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the channel measurements being based on a plurality of spatial directions; and determine whether the channel measurements meet criteria for accessing the shared radio frequency band without medium access restrictions; the transceiver being configured to: in response to determining that the channel measurements meet the criteria, send a first communication signal in the shared radio frequency band in a first spatial direction without medium access restrictions, the plurality of spatial directions including the first spatial direction.

[0122] The wireless communication device may also include one or more of the following features. For example, the wireless communication device may include: wherein the processor configured to determine whether the channel measurement meets the standard is also configured to determine whether each measurement determined according to a set of consecutive measurement opportunities in a plurality of measurement opportunities meets the standard. The processor configured to determine whether the channel measurement meets the standard is also configured to determine whether each measurement value determined according to a set of consecutive measurement opportunities in a plurality of measurement opportunities meets a threshold. The processor configured to determine whether the channel measurement meets the standard is also configured to determine whether a predetermined number of channel measurements determined according to a set of measurement opportunities in a plurality of measurement opportunities meet the standard. The medium access restriction includes a beam width threshold, and wherein the transceiver configured to send the first communication signal is also configured to send the first communication signal using a transmit beam having a beam width that does not meet the beam width threshold. The medium access restriction includes a transmit power threshold, and wherein the transceiver for sending the first communication signal is also configured to send the first communication signal using a transmit power that does not meet the transmit power threshold. The medium access restriction includes a transmit power spectral density (PSD) threshold, and wherein the transceiver configured to send the first communication signal is further configured to send the first communication signal having a transmit PSD that does not meet the transmit PSD threshold. The medium access restriction includes a duty cycle threshold, and wherein the transceiver configured to send the first communication signal is further configured to send the first communication signal based on a duty cycle that does not meet the duty cycle threshold. The medium access restriction includes listen before talk (LBT), and wherein the transceiver for sending the first communication signal is further configured to send the first communication signal without performing LBT. The processor is further configured to: perform a second channel measurement in a shared radio frequency band during a second plurality of measurement opportunities spaced apart in time, the second channel measurement being based on a plurality of spatial directions; and the transceiver is further configured to: in response to determining that the second channel measurement fails to meet a criterion for accessing the shared radio frequency band without the medium access restriction, send a second communication signal in the shared radio frequency band in a second spatial direction with the medium access restriction. The transceiver configured to send the second communication signal is further configured to send the second communication signal using a transmit beam with a beam width that satisfies a beam width threshold based on medium access restrictions. The transceiver configured to send the second communication signal is further configured to send the second communication signal using a transmit power that satisfies a transmit power threshold based on medium access restrictions. The transceiver configured to send the second communication signal is further configured to send the second communication signal having a transmit PSD that satisfies a transmit power spectral density (PSD) threshold based on medium access restrictions. The transceiver configured to send the second communication signal is further configured to send the second communication signal based on a duty cycle that satisfies a duty cycle threshold based on medium access restrictions.The processor is further configured to perform a listen before talk (LBT) procedure prior to the second communication signal based on the medium access restriction.The shared radio frequency band is a millimeter wave (mmWav) unlicensed band.

[0123] Other aspects of the present disclosure include a non-transitory computer-readable medium having program code recorded thereon. The non-transitory computer-readable medium includes code for causing a wireless communication device to perform channel measurements in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the channel measurements being based on a plurality of spatial directions. The medium also includes code for causing the wireless communication device to determine whether the channel measurements meet a criterion for accessing a shared radio frequency band without medium access restrictions. The medium also includes code for causing the wireless communication device to send a first communication signal in a first spatial direction in a shared radio frequency band without medium access restrictions in response to determining that the channel measurements meet the criterion, the plurality of spatial directions including the first spatial direction.

[0124] The non-transitory computer-readable medium may also include one or more of the following features. For example, the non-transitory computer-readable medium of the code for causing the wireless communication device to determine whether the channel measurement meets the standard is also configured to: determine whether each measurement opportunity determined according to a set of consecutive measurement opportunities in a plurality of measurement opportunities meets the standard. The code for causing the wireless communication device to determine whether the channel measurement meets the standard is also configured to: determine whether each measurement value determined according to a set of consecutive measurement opportunities in a plurality of measurement opportunities meets a threshold. The code for causing the wireless communication device to determine whether the channel measurement meets the standard is also configured to: determine whether a predetermined number of channel measurements determined according to a set of measurement opportunities in a plurality of measurement opportunities meet the standard. The medium access restriction includes a beam width threshold, and wherein the code for causing the wireless communication device to send the first communication signal is also configured to: send the first communication signal using a transmit beam having a beam width that does not meet the beam width threshold. The medium access restriction includes a transmit power threshold, and wherein the code for causing the wireless communication device to send the first communication signal is also configured to send the first communication signal using a transmit power that does not meet the transmit power threshold. The medium access restriction includes a transmit power spectral density (PSD) threshold, and wherein the code for causing the wireless communication device to send the first communication signal is further configured to: send the first communication signal having a transmit PSD that does not meet the transmit PSD threshold. The medium access restriction includes a duty cycle threshold, and wherein the code for causing the wireless communication device to send the first communication signal is further configured to: send the first communication signal based on a duty cycle that does not meet the duty cycle threshold. The medium access restriction includes listen before talk (LBT), and wherein the code for causing the wireless communication device to send the first communication signal is further configured to: send the first communication signal without performing LBT. The non-transitory computer-readable medium may also include: code for causing the wireless communication device to perform a second channel measurement in the shared radio frequency band during a second plurality of measurement opportunities spaced apart in time, the second channel measurement being based on the plurality of spatial directions; and code for causing the wireless communication device to send a second communication signal in the shared radio frequency band in a second spatial direction with the medium access restriction in response to determining that the second channel measurement fails to meet the criteria for accessing the shared radio frequency band channel without the medium access restriction. The code for causing the wireless communication device to send a second communication signal is further configured to: based on the medium access restriction, use a transmit beam with a beam width that satisfies a beam width threshold to send the second communication signal. The code for causing the wireless communication device to send a second communication signal is further configured to: based on the medium access restriction, use a transmit power that satisfies a transmit power threshold to send the second communication signal. The code for causing the wireless communication device to send a second communication signal is further configured to: based on the medium access restriction, send a second communication signal with a transmit PSD that satisfies a transmit power spectral density (PSD) threshold.The code for causing the wireless communication device to send a second communication signal is also configured to: send the second communication signal based on a duty cycle that satisfies a duty cycle threshold based on a medium access restriction. The non-transitory computer-readable medium may also include code for causing the wireless communication device to perform a listen-before-talk (LBT) process before sending the second communication signal based on the medium access restriction. The shared radio frequency band is a millimeter wave (mmWav) unlicensed band.

[0125] Other aspects of the present disclosure include a wireless communication device. The wireless communication device includes a unit for performing channel measurements in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the channel measurements being based on a plurality of spatial directions. The device also includes a unit for determining whether the channel measurements meet a criterion for accessing the shared radio frequency band without medium access restrictions. The device also includes a unit for transmitting a first communication signal in a shared radio frequency band in a first spatial direction without medium access restrictions in response to determining that the channel measurements meet the criterion, the plurality of spatial directions including the first spatial direction.

[0126] The wireless communication device may also include one or more of the following features. For example, the wireless communication device may include: wherein the unit for determining whether the channel measurement meets the standard is also configured to determine whether each measurement determined according to a set of consecutive measurement opportunities in a plurality of measurement opportunities meets the standard. The unit for determining whether the channel measurement meets the standard is also configured to determine whether each measurement value determined according to a set of consecutive measurement opportunities in a plurality of measurement opportunities meets a threshold. The unit for determining whether the channel measurement meets the standard is also configured to determine whether a predetermined number of channel measurements determined according to a set of measurement opportunities in a plurality of measurement opportunities meet the standard. The medium access restriction includes a beam width threshold, and wherein the unit for sending the first communication signal is also configured to send the first communication signal using a transmit beam having a beam width that does not meet the beam width threshold. The medium access restriction includes a transmit power threshold, and wherein the unit for sending the first communication signal is also configured to send the first communication signal using a transmit power that does not meet the transmit power threshold. The medium access restriction includes a transmit power spectral density (PSD) threshold, and wherein the means for sending the first communication signal is further configured to send the first communication signal having a transmit PSD that does not meet the transmit PSD threshold. The medium access restriction includes a duty cycle threshold, and wherein the means for sending the first communication signal is further configured to send the first communication signal based on a duty cycle that does not meet the duty cycle threshold. The medium access restriction includes listen before talk (LBT), and wherein the means for sending the first communication signal is further configured to send the first communication signal without performing LBT. The wireless communication device may also include: a means for performing a second channel measurement in a shared radio frequency band during a second plurality of measurement opportunities spaced apart in time, the performing the second channel measurement being based on a plurality of spatial directions; and a means for sending a second communication signal in a shared radio frequency band in a second spatial direction in response to determining that the second channel measurement fails to meet a criterion for accessing the shared radio frequency band without the medium access restriction, in the case of the medium access restriction. The unit for sending the second communication signal is also configured to send the second communication signal using a transmit beam with a beam width that satisfies a beam width threshold based on medium access restrictions. The unit for sending the second communication signal is also configured to send the second communication signal using a transmit power that satisfies a transmit power threshold based on medium access restrictions. The unit for sending the second communication signal is also configured to send a second communication signal having a transmit PSD that satisfies a transmit power spectral density (PSD) threshold based on medium access restrictions. The unit for sending the second communication signal is also configured to send the second communication signal based on a duty cycle that satisfies a duty cycle threshold based on medium access restrictions. The unit for sending the second communication signal is also configured to perform a listen-before-talk (LBT) process before sending the second communication signal based on medium access restrictions.The shared radio frequency band is the millimeter wave (mmWav) unlicensed band.

[0127] Any of a variety of different technologies and methods may be used to represent information and signals. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0128] The various illustrative blocks and modules described in conjunction with the disclosure herein may be implemented or executed using a general purpose processor, DSP, ASIC, 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 an alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, a combination of one or more microprocessors and a DSP core, or any other such configuration).

[0129] The functions described herein can be implemented with hardware, software executed by a processor, firmware, or any combination thereof. If implemented with software executed by a processor, the function can be stored on a computer-readable medium or transmitted by a computer-readable medium as one or more instructions or codes. Other examples and implementations are within the scope of the disclosure and the appended claims. For example, due to the nature of software, the functions described above can be implemented using software, hardware, firmware, hard wiring, or any combination of these executed by a processor. The features that implement the functions can also be physically placed at various locations, including being distributed so that the parts that implement the functions at different physical locations. In addition, as used herein (including in the claims), "or" (for example, a list of entries ending with phrases such as "at least one of" or "one or more of") as used in a list of entries indicates an inclusive list, so 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).

[0130] As will be apparent to those skilled in the art by now and depending on the specific application at hand, many modifications, substitutions and variations may be made to the materials, devices, configurations and methods of use of the apparatus of the present disclosure without departing from its spirit and scope. In view of this, the scope of the present disclosure should not be limited to the scope of the specific embodiments illustrated and described herein, as they are merely by way of some examples thereof, but should be fully commensurate with the scope of the appended claims and their functional equivalents.

Claims

1. A method of wireless communication, comprising: performing, by a wireless communication device, channel measurements in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, said performing said channel measurements being based on a plurality of spatial directions; determining, by the wireless communication device, whether the channel measurement satisfies criteria for accessing the shared radio frequency band without medium access restrictions; as well as In response to determining that the channel measurement satisfies the criterion, transmitting, by the wireless communication device, a first communication signal in the shared radio frequency band in a first spatial direction without the medium access restriction, the plurality of spatial directions including the first spatial direction, The medium access restriction includes at least one of a beam width threshold, a transmit power threshold, a transmit power spectral density (PSD) threshold or a duty cycle threshold.

2. The method according to claim 1, wherein: The channel measurement is a long-term channel measurement.

3. The method according to claim 1, wherein: Determining whether the channel measurement meets the standard includes: It is determined whether each measurement value determined from a set of consecutive measurement opportunities in the plurality of measurement opportunities meets the criterion.

4. The method according to claim 3, wherein: Determining whether the channel measurement meets the standard includes: It is determined whether each measurement value determined from the set of consecutive measurement opportunities in the plurality of measurement opportunities satisfies a threshold.

5. The method according to claim 1, wherein: Determining whether the channel measurement meets the standard includes: It is determined whether a predetermined number of channel measurements determined according to a set of measurement opportunities in the plurality of measurement opportunities satisfies the criterion.

6. The method according to claim 1, wherein: The medium access restriction comprises a beam width threshold, and wherein the sending the first communication signal comprises: The first communication signal is transmitted by the wireless communication device using a transmission beam having a beamwidth that does not satisfy the beamwidth threshold.

7. The method according to claim 1, wherein: The medium access restriction comprises a transmit power threshold, and wherein the sending the first communication signal comprises: The first communication signal is sent by the wireless communication device using a transmit power that does not satisfy the transmit power threshold.

8. The method according to claim 1, wherein: The medium access restriction comprises a transmit power spectral density (PSD) threshold, and wherein the sending the first communication signal comprises: The first communication signal is sent by the wireless communication device having a transmit PSD that does not satisfy the transmit PSD threshold.

9. The method according to claim 1, wherein: The medium access restriction comprises a duty cycle threshold, and wherein the sending the first communication signal comprises: The first communication signal is transmitted by the wireless communication device based on a duty cycle that does not satisfy the duty cycle threshold.

10. The method according to claim 1, wherein: The medium access restriction includes listen before talk (LBT), and wherein sending the first communication signal includes: The first communication signal is transmitted without performing the LBT.

11. The method according to claim 1, further comprising: performing, by the wireless communication device, a second channel measurement in the shared radio frequency band during a second plurality of measurement opportunities spaced apart in time, the performing the second channel measurement being based on the plurality of spatial directions; as well as In response to determining that the second channel measurement fails to meet the criteria for accessing the shared radio frequency band without the medium access restriction, the wireless communication device sends a second communication signal in the shared radio frequency band in a second spatial direction with the medium access restriction.

12. The method according to claim 11, wherein: The second channel measurement is a long-term channel measurement.

13. The method according to claim 11, wherein: The sending the second communication signal comprises: The second communication signal is transmitted by the wireless communication device using a transmission beam having a beamwidth that satisfies a beamwidth threshold based on the medium access restriction.

14. The method according to claim 11, wherein: The sending the second communication signal comprises: The second communication signal is sent by the wireless communication device using a transmission power that satisfies a transmission power threshold based on the medium access restriction.

15. The method according to claim 11, wherein: The sending the second communication signal comprises: The second communication signal having a transmit power spectral density (PSD) satisfying a transmit power spectral density (PSD) threshold is sent by the wireless communication device based on the medium access restriction.

16. The method according to claim 11, wherein: The sending the second communication signal comprises: The second communication signal is sent by the wireless communication device based on a duty cycle that satisfies a duty cycle threshold based on the medium access restriction.

17. The method according to claim 11, wherein: The sending the second communication signal comprises: A listen-before-talk (LBT) procedure is performed by the wireless communication device before sending the second communication signal based on the medium access restriction.

18. A wireless communication device, comprising: The processor is configured as: performing channel measurements in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the channel measurements being based on a plurality of spatial directions; as well as determining whether the channel measurements meet criteria for accessing the shared radio frequency band without medium access restrictions; and a transceiver coupled to the processor, wherein the transceiver is configured to: In response to determining that the channel measurement satisfies the criterion, transmitting a first communication signal in the shared radio frequency band in a first spatial direction without the medium access restriction, the plurality of spatial directions including the first spatial direction, The medium access restriction includes at least one of a beam width threshold, a transmit power threshold, a transmit power spectral density (PSD) threshold or a duty cycle threshold.

19. The wireless communication device according to claim 18, wherein: The channel measurement is a long-term channel measurement.

20. The wireless communication device of claim 18, wherein: The processor configured to determine whether the channel measurement meets the criterion is further configured to: It is determined whether each measurement value determined from a set of consecutive measurement opportunities in the plurality of measurement opportunities meets the criterion.

21. The wireless communication device of claim 18, wherein: The processor configured to determine whether the channel measurement meets the criterion is further configured to: It is determined whether a predetermined number of channel measurements determined according to a set of measurement opportunities in the plurality of measurement opportunities satisfies the criterion.

22. The wireless communication device of claim 18, wherein: The transceiver configured to send the first communication signal is further configured to: The first communication signal is sent based on at least one of the following: a transmit beam having a beamwidth that does not satisfy the beamwidth threshold; a transmit power that does not meet the transmit power threshold; a transmit PSD that does not meet the transmit PSD threshold; or A duty cycle that does not satisfy the duty cycle threshold.

23. The wireless communication device of claim 18, wherein: The medium access restriction comprises listen before talk (LBT), and wherein the transceiver configured to send the first communication signal is further configured to: The first communication signal is transmitted without performing the LBT.

24. The wireless communication device of claim 18, wherein: The processor is further configured to: performing a second channel measurement in the shared radio frequency band during a second plurality of measurement opportunities spaced apart in time, the second channel measurement being a long-term channel measurement based on the plurality of spatial directions; and The transceiver is further configured to: In response to determining that the second channel measurement fails to meet the criteria for accessing the shared radio frequency band without the medium access restriction, a second communication signal is transmitted in the shared radio frequency band in a second spatial direction with the medium access restriction.

25. The wireless communication device according to claim 24, wherein: The transceiver configured to send the second communication signal is further configured to: The second communication signal is sent based on at least one of the following: a transmit beam having a beamwidth that satisfies a beamwidth threshold associated with the medium access restriction; a transmit power that satisfies a transmit power threshold associated with the medium access restriction; a transmit power spectral density (PSD) that satisfies a transmit PSD threshold associated with the medium access restriction; or A duty cycle satisfies a duty cycle threshold associated with the medium access restriction.

26. The wireless communication device of claim 24, wherein: The processor is further configured to: Based on the medium access restriction, a listen before talk (LBT) procedure is performed prior to the second communication signal.

27. A non-transitory computer readable medium having program code recorded thereon, the program code comprising: code for causing a wireless communication device to perform channel measurements in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the channel measurements being based on a plurality of spatial directions; code for causing the wireless communication device to determine whether the channel measurements satisfy criteria for accessing the shared radio frequency band without medium access restrictions; as well as code for causing the wireless communication device to transmit a first communication signal in the shared radio frequency band in a first spatial direction without the medium access restriction in response to determining that the channel measurement satisfies the criterion, the plurality of spatial directions including the first spatial direction, The medium access restriction includes at least one of a beam width threshold, a transmit power threshold, a transmit power spectral density (PSD) threshold or a duty cycle threshold.

28. The non-transitory computer readable medium of claim 27, wherein: The channel measurement is a long-term channel measurement.

29. The non-transitory computer readable medium of claim 27, wherein: The code for causing the wireless communication device to determine whether the channel measurement meets the criterion is further configured to: It is determined whether each measurement value determined from a set of consecutive measurement opportunities in the plurality of measurement opportunities meets the criterion.

30. The non-transitory computer readable medium of claim 27, wherein: The code for causing the wireless communication device to determine whether the channel measurement meets the criterion is further configured to: It is determined whether a predetermined number of channel measurements determined according to a set of measurement opportunities in the plurality of measurement opportunities satisfies the criterion.

31. The non-transitory computer readable medium of claim 27, wherein: The code for causing the wireless communication device to transmit the first communication signal is further configured to: The first communication signal is sent based on at least one of the following: a transmit beam having a beamwidth that does not satisfy the beamwidth threshold; a transmit power that does not meet the transmit power threshold; a transmit PSD that does not meet the transmit PSD threshold; or A duty cycle that does not satisfy the duty cycle threshold.

32. A wireless communication device, comprising: means for performing channel measurements in a shared radio frequency band during a plurality of measurement opportunities spaced apart in time, the channel measurements being based on a plurality of spatial directions; means for determining whether the channel measurements satisfy criteria for accessing the shared radio frequency band without medium access restrictions; as well as means for transmitting, in response to determining that the channel measurement satisfies the criterion, a first communication signal in the shared radio frequency band in a first spatial direction without the medium access restriction, the plurality of spatial directions including the first spatial direction, The medium access restriction includes at least one of a beam width threshold, a transmit power threshold, a transmit power spectral density (PSD) threshold or a duty cycle threshold.

33. The wireless communication device of claim 32, wherein: The channel measurement is a long-term channel measurement.

34. The wireless communication device of claim 32, wherein: The unit for determining whether the channel measurement meets the criterion is further configured to: It is determined whether each measurement value determined from a set of consecutive measurement opportunities in the plurality of measurement opportunities meets the criterion.

35. The wireless communication device of claim 32, wherein: The unit for sending the first communication signal is further configured to: The first communication signal is sent based on at least one of the following: a transmit beam having a beamwidth that does not satisfy the beamwidth threshold; a transmit power that does not meet the transmit power threshold; a transmit PSD that does not meet the transmit PSD threshold; or A duty cycle that does not satisfy the duty cycle threshold.

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