Flexible frame structure for directional unlicensed access in sub-terahertz bands

Abstract

A system comprising: a user equipment (UE) configured to: receive channel access scheduling information, the channel access scheduling information comprising at least one frame having a configurable number of data transmission slots, wherein a frame comprises a downlink signaling phase, a data transmission phase, an additional scheduling phase, and an additional data transmission phase; and transmit data and clear channel assessment (CCA) information, wherein the data and CCA information are transmitted in one or more data transmission slots selected from the configurable number of data transmission slots based on the channel access scheduling information; and an access point (AP) configured to transmit the channel access scheduling information to the UE and receive the data and clear channel assessment (CCA) information from the UE.

Description

Priority is incorporated by reference

[0001] This application claims priority to U.S. Application Serial No. 18 / 534,028, filed December 8, 2023, entitled “Flexible Frame Structures For Directional Unlicensed Access In Sub-Terahertz Band,” the entire contents of which are incorporated herein by reference. Background Technology

[0002] The sub-THz frequency range is a promising candidate for 6G wireless networks, primarily due to its massive bandwidth enabling transmission rates of hundreds of gigabits per second (Gbps). However, compared to omnidirectional systems, the sub-THz frequency range introduces additional complexities, requiring new hardware and technologies to handle the high frequency range. In the case of unlicensed spectrum, beam processing and user equipment (UE) access become even more complex due to various factors.

[0003] The Asia-Pacific Hertz (APH) spectrum is envisioned for use by applications requiring high data rates and low-latency communication links. This spectrum is expected to operate in an unlicensed manner. Therefore, reliably providing low latency and high data rates can be challenging due to spectrum sharing. Typically, random access techniques (e.g., carrier-sensing multiple access / carrier aggregation (CSMA / CA)) are used in unlicensed spectrum; however, random access cannot be applied due to the high directivity of APH communication and the need for beamforming and tracking, and scheduled access must be used. Random access techniques also suffer from high power consumption because the duty cycle cycles drastically increase latency (the duty cycle is non-coordinated). However, scheduled access also presents potential problems when applied in unlicensed spectrum, such as potentially wasted communication resources and latency.

[0004] It has been determined that methods, equipment, and flexible frame structures are needed to support directional unlicensed access in the Asia-Pacific Hertz band. Summary of the Invention

[0005] Some example implementations relate to a system comprising: a user equipment (UE) configured to: receive channel access scheduling information including at least one frame having a configurable number of data transmission slots, wherein the frame includes a downlink signaling phase, a data transmission phase, an additional scheduling phase, and an additional data transmission phase; and transmit data and free channel assessment (CCA) information, wherein the data and CCA information are transmitted in one or more data transmission slots selected from the configurable number of data transmission slots based on the channel access scheduling information. The system also includes an access point (AP) configured to transmit the channel access scheduling information to the UE and receive the data and free channel assessment (CCA) information from the UE.

[0006] Other example implementations relate to an apparatus for a user equipment (UE) including processing circuitry configured to: decode channel access scheduling information received from an access point (AP), the channel access scheduling information including at least one frame having a configurable number of data transmission slots; and configure transceiver circuitry to transmit data and idle channel assessment (CCA) information to the AP, wherein the data and CCA information are transmitted in one or more data transmission slots selected from the configurable number of data transmission slots based on the channel access scheduling information.

[0007] Another example implementation relates to an access point (AP) apparatus comprising processing circuitry configured to: configure transceiver circuitry to transmit channel access scheduling information to one or more user equipments (UEs) among a plurality of user equipments (UEs), the channel access scheduling information including at least one frame having a configurable number of data transmission slots; and decode data and free channel assessment (CCA) information from signaling received from one or more of the plurality of UEs, wherein the data and CCA information are transmitted in one or more data transmission slots selected from the configurable number of data transmission slots based on the channel access scheduling information. Attached Figure Description

[0008] Figure 1 Example network layouts based on various example implementation schemes are shown.

[0009] Figure 2 Example user equipment (UE) based on various example implementation schemes is shown.

[0010] Figure 3 Example base stations based on various example implementation schemes are shown.

[0011] Figure 4 This is an example scheduling channel access frame structure for scheduling directed unlicensed access, based on an example implementation scheme.

[0012] Figure 5 This is an example scheduling channel access frame structure that highlights the example DL signaling phase and the additional signaling phase according to the example implementation scheme.

[0013] Figure 6 This is an example scheduling channel access frame structure that highlights the example data transmission phase according to the example implementation.

[0014] Figure 7 This is an example diagram illustrating an example channel sensing period in an example scheduling channel access frame structure according to an example implementation scheme.

[0015] Figure 8 This is an example diagram illustrating an example additional signaling phase in an example scheduling channel access frame structure according to an example implementation scheme.

[0016] Figure 9 This is an example flowchart illustrating the exchange of information between the AP and the UE during the example additional signaling phase according to the example implementation scheme. Detailed Implementation

[0017] The exemplary embodiments can be further understood by referring to the following description and related figures, wherein the same elements have the same reference numerals. The exemplary embodiments relate to wireless communication devices, and more specifically to methods, devices, and flexible frame structures for supporting directed unlicensed access in the Asia-Pacific Hertz (sub-THz) band.

[0018] Example embodiments are described with reference to user equipment (UE). However, references to the UE are provided for illustrative purposes only. The example embodiments can be used with any electronic component that can establish a connection to a network and is configured with hardware, software, and / or firmware for exchanging information and data with the network. Therefore, the UE described herein is used to represent any suitable type of electronic component.

[0019] Example implementations are also described with reference to fifth-generation (5G) new radio (NR) networks and next-generation node B (gNB). However, the references to 5G NR networks and gNBs are provided for illustrative purposes only. The example implementations can be used with any suitable type of network (e.g., 5G advanced network, 6G network, etc.) and base station.

[0020] The UE can perform measurements on one or more neighboring cells using specific downlink reference signals, such as Signal Synchronization Block (SSB) or Channel State Information (CSI)-Reference Signal (RS). These measurements can be based on SSB, CSI-RS, or any other suitable downlink resource. Measurement metrics can be L1 Reference Signal Received Power (RSRP), L1 Signal-to-Interference-Noise Ratio (SINR), L1 Reference Signal Received Quality (RSRQ), or any other suitable type of metric. However, any reference to a specific type of measurement, reference signal, or metric is provided for illustrative purposes only. The example implementation can be applied to any suitable type of measurement, reference signal, or metric.

[0021] Figure 1 An example network arrangement 100 according to various example implementations is shown. The example network arrangement 100 includes a UE 110. The UE 110 can be any type of electronic component configured to communicate via a network, such as a mobile phone, tablet computer, desktop computer, smartphone, phablet, embedded device, wearable device, Internet of Things (IoT) device, etc. A real network arrangement may include any number of UEs used by any number of users. Therefore, the example of a single UE 110 is provided for illustrative purposes only.

[0022] UE 110 can be configured to communicate with one or more networks. In the example of network configuration 100, the network with which UE 110 can wirelessly communicate is 5G NR Radio Access Network (RAN) 120. However, UE 110 can also communicate with other types of networks, such as sixth-generation (6G) RAN, 5G cloud RAN, next-generation RAN (NG-RAN), Long Term Evolution (LTE) RAN, legacy cellular networks, wireless local area networks (WLANs), etc., and UE 110 can also communicate with the network via a wired connection. Referring to the example implementation, UE 110 can establish a connection with 5G NR RAN 120. Therefore, UE 110 may have at least a 5G NR chipset to communicate with 5G NR RAN 120.

[0023] The 5G NR RAN 120 may be part of a cellular network that can be deployed by network operators (e.g., Verizon, AT&T, T-Mobile, etc.). The 5G NR RAN 120 may include base stations or access nodes (NodeB, eNodeB, HeNB, eNB, gNB, gNodeB, macrocell, microcell, small cell, femtocell, etc.) configured to transmit and receive traffic from UEs equipped with appropriate cellular chipsets. As used herein, the terms “base station,” “access node,” “access point,” etc., can describe equipment that provides radio baseband functionality for data and / or voice connections between the network and one or more users. These access nodes may be referred to as BS, gNB, RAN node, eNB, NodeB, RSU, TRxP, or TRP, etc., and may include ground stations (e.g., ground access points) or satellite stations that provide coverage within a geographic area (e.g., a cell). In fact, in some implementations, a UE (such as UE 110 described herein) may be used as an access point.

[0024] In network deployment 100, a 5G NR RAN 120 deploys a gNB 120A. The gNB 120A can be configured with multiple TRPs. Each TRP can represent one or more components configured to transmit and / or receive signals. In some implementations, multiple TRPs can be deployed locally on the gNB 120A. In other implementations, multiple TRPs can be distributed across different locations and connected to the gNB 120A via backhaul connections. For example, multiple small cells can be deployed at different locations and connected to the gNB 120A. However, these examples are provided for illustrative purposes only. TRPs are configured to adapt to a variety of different conditions and deployment scenarios. Therefore, any reference to a TRP as a specific network component or to multiple TRPs deployed in a particular deployment is merely illustrative. The TRPs described herein can represent any type of network component configured to transmit and / or receive beams.

[0025] Any association procedure can be performed to connect UE 110 to 5G NR RAN 120. For example, as discussed above, 5G NR RAN 120 can be associated with a specific cellular provider where UE 110 and / or its user have protocol and credential information (e.g., stored on a SIM card). Upon detecting the presence of 5G NR RAN 120, UE 110 can send the corresponding credential information to associate with 5G NR RAN 120. More specifically, UE 110 can be associated with a specific base station (e.g., gNB 120A).

[0026] Network deployment 100 also includes a cellular core network 130, an Internet 140, an IP Multimedia Subsystem (IMS) 150, and a network services backbone 160. The cellular core network 130 can refer to an interconnected set of components that manage the operation and traffic of the cellular network. It may include an evolved packet core (EPC) and / or a 5G core (5GC). The cellular core network 130 also manages the traffic flowing between the cellular network and the Internet 140. The IMS 150 can generally be described as an architecture for delivering multimedia services to the UE 110 using IP protocols. The IMS 150 can communicate with the cellular core network 130 and the Internet 140 to provide multimedia services to the UE 110. The network services backbone 160 communicates directly or indirectly with the Internet 140 and the cellular core network 130. The network services backbone 160 can generally be described as a collection of components (e.g., servers, network storage deployments, etc.) that implement a set of services that can be used to extend the functionality of the UE 110 in communicating with various networks.

[0027] Figure 2 Example UE 110 according to various example implementations is shown. (Refer to...) Figure 1 The network layout 100 is used to describe UE 110. UE 110 may include a processor 205, a memory layout 210, a display device 215, an input / output (I / O) device 220, a transceiver 225, and other components 230. Other components 230 may include, for example, audio input devices, audio output devices, power supplies, data acquisition devices, ports for electrically connecting UE 110 to other electronic devices, etc.

[0028] Processor 205 can be configured to execute multiple engines for UE 110. For example, engines may include mTRP engine 235, sTRP engine 240, and channel access scheduling engine 245. mTRP engine 235 can perform various operations related to mTRP operations. sTRP engine 240 can perform various operations related to sTRP operations. In 5G NR, the Unified Transmission Configuration Indicator (TCI) framework is designed to facilitate streamlined mTRP operations. To provide some general examples, mTRP engine 235 can perform operations such as, but not limited to, dynamically switching between mTRP and sTRP modes, updating CC groups for mTRP operations, and determining the default downlink beam / TCI state for mTRPPDSCH reception. Channel access scheduling engine 245 can perform any steps necessary for scheduling channel access for data transmission to and from UE 110, such as between UE 110 and an access point (AP).

[0029] The engines 235, 240, and 245 referenced above are provided merely as illustrative examples of applications (e.g., programs) executed by processor 205. The functionality associated with engines 235, 240, and 245 may also be represented as separate combined components of UE 110, or as modular components coupled to UE 110, such as integrated circuits with or without firmware. For example, the integrated circuit may include input circuitry for receiving signals and processing circuitry for processing signals and other information. The engines may also be embodied as one application or multiple independent applications. Furthermore, in some UEs, the functionality described for processor 205 is split among two or more processors, such as a baseband processor and an application processor. Example implementations may be implemented according to any of these or other configurations of the UE.

[0030] Memory arrangement 210 may be a hardware component configured to store data related to operations performed by UE 110. Display device 215 may be a hardware component configured to display data to a user, while I / O device 220 may be a hardware component enabling a user to input data. Display device 215 and I / O device 220 may be separate components or may be integrated together (such as a touchscreen). Transceiver 225 may be a hardware component configured to establish connections with 5G NR-RAN 120, LTE-RAN (not shown), legacy RAN (not shown), WLAN (not shown), etc. Accordingly, transceiver 225 may operate on a variety of different frequencies or channels (e.g., a continuous set of frequencies).

[0031] Transceiver 225 includes circuitry configured to transmit and / or receive signals (e.g., control signals, data signals). Such signals may be encoded using information used to implement any of the methods described herein. Processor 205 may be operatively coupled to transceiver 225 and configured to receive signals from and / or transmit signals to transceiver 225. Processor 205 may be configured to encode and / or decode signals (e.g., signaling from a base station in a network) for use in implementing any of the methods described herein.

[0032] Figure 3An example base station 300 according to various example implementations is shown. Base station 300 may represent a gNB 120A or any other type of access node that UE 110 can use to establish connections and manage network operations. As used herein, the term "base station" may also refer to "access node," "access point," etc., and may be described as equipment that provides radio baseband functionality for data and / or voice connections between the network and one or more users. These base stations and access nodes may be referred to as BS, gNB, RAN node, eNB, Node B, RSU, TRxP, or TRP, etc., and may include ground stations (e.g., ground access points) or satellite stations that provide coverage within a geographic area (e.g., a cell).

[0033] Base station 300 may include processor 305, memory arrangement 310, input / output (I / O) devices 315, transceiver 320, multiple TRPs 330, and other components 325. Other components 325 may include, for example, audio input devices, audio output devices, batteries, data acquisition devices, ports for electrically connecting base station 300 to other electronic devices and / or power sources, TxRUs, transceiver chains, antenna elements, antenna panels, etc.

[0034] As indicated above, in some scenarios, multiple TRPs 330 may be deployed locally at base station 300. In other scenarios, one or more of the multiple TRPs 330 may be deployed at a physical location remote from base station 300 and connected to the base station via a backhaul connection. Base station 300 may be configured to control the multiple TRPs 330 and perform operations such as, but not limited to, allocating resources, configuring reference signals, and implementing beam management techniques.

[0035] Processor 305 can be configured to execute multiple engines of base station 300. For example, engines may include mTRP engine 335, sTRP engine 340, and channel access scheduling engine 345. sTRP engine 340 can perform various operations related to sTRP operation. mTRP engine 335 can perform various operations related to mTRP operation. To provide some general examples, mTRP engine 335 can perform operations such as, but not limited to, sending signals to trigger UE 110 to dynamically switch between mTRP mode and sTRP mode, sending information to update the CC group for mTRP operation, and indicating the default downlink beam / TCI state for mTRP PDSCH reception. Channel access scheduling engine 345 can perform any steps necessary for scheduling channel access for data transmission to and from base station 300 (such as between base station 300 and UE).

[0036] The engines 335, 340, and 345 described above, as applications (e.g., programs) executed by processor 305, are merely examples. The functionality associated with engines 335, 340, and 345 may also be represented as separate integrated components of base station 300, or as modular components coupled to base station 300, such as integrated circuits with or without firmware. For example, the integrated circuit may include input circuitry for receiving signals and processing circuitry for processing signals and other information. Furthermore, in some base stations, the functionality described for processor 305 is split among multiple processors (e.g., baseband processor, application processor, etc.). Example implementations may be implemented according to any of these or other configurations of the base station.

[0037] The memory 310 may be a hardware component configured to store data related to operations performed by the base station 300. The I / O device 315 may be a hardware component or port that enables a user to interact with the base station 300.

[0038] Transceiver 320 may be a hardware component configured to exchange data with UE 110 and any other UE in network arrangement 100. Transceiver 320 may operate on a variety of different frequencies or channels (e.g., a continuous set of frequencies). Therefore, transceiver 320 may include one or more components (e.g., radio components) to enable data exchange with various networks and UEs. Transceiver 320 includes circuitry configured to transmit and / or receive signals (e.g., control signals, data signals). Such signals may be encoded using information used to implement any of the methods described herein. Processor 305 may be operatively coupled to transceiver 320 and configured to receive signals from and / or transmit signals to transceiver 320. Processor 305 may be configured to encode and / or decode signals (e.g., signaling from a UE) for use in implementing any of the methods described herein.

[0039] As previously mentioned, the Asia-Pacific Hertz (APH) frequency range is a promising candidate for 6G wireless networks, primarily due to its massive bandwidth capable of achieving transmission rates of hundreds of Gbps. Due to the high directivity required in APH systems, eavesdropping is significantly more difficult compared to omnidirectional systems, and a higher level of privacy is achieved by default. However, the APH frequency range also introduces additional complexities compared to omnidirectional systems. For example, new hardware and PA technologies may be required to handle the high frequencies. Indoor use cases with limited range will be particularly relevant due to the significant path loss. Overcoming path loss requires high antenna gain achieved via antenna arrays with numerous antennas, which could result in narrow beams for all data transmissions.

[0040] Furthermore, beamforming and UE access are even more complex in unlicensed spectrum scenarios due to the following: Unlike 3GPP scenarios, conflicts can occur between different users using the same radio access technology (RAT) or different RATs on the same spectrum. Regulations may require directional (i.e., beamforming) idle channel assessment (beamforming listen-before-tell (LBT)). Multi-user scheduling and coordination are significantly more difficult compared to licensed spectrum use.

[0041] The Asia-Pacific Hertz (APH) spectrum is envisioned for use by applications requiring high data rates and low-latency communication links. This spectrum is expected to operate in an unlicensed manner. Therefore, providing reliability, low latency, and high data rates can be challenging due to spectrum sharing. For example, spectrum access rules exist, such as the EU harmonized standard ETSI EN 302 567, which is extendable to APH. Channel access rules, such as “short control signaling,” can be applied. For instance, a channel access rule could include allowing transmissions (Tx) of up to 10 milliseconds (ms) within 100 ms without any restrictions, where normal transmission has a maximum channel occupancy time (COT) of 5 ms, with an 8 microsecond (µs) idle period between / before the 5 ms COT period. However, these are merely examples, as there are no current regulatory requirements for APH, and example implementations can be implemented in networks applying any type of channel access rule or corresponding parameters for channel access rules.

[0042] Random access techniques (e.g., CSMA / CA) are typically used in unlicensed spectrum. However, due to the high directivity of Asia-Pacific Hertz communications and the need for beamforming and tracking, random access cannot be applied, and scheduled access must be used. Random access techniques also suffer from high power consumption because the duty cycle cyclically increases latency sharply (the duty cycle is non-coordinated). However, scheduled access has the following problems when applied in unlicensed spectrum: Access reservation, free channel assessment (CCA), and channel sounding must be performed to avoid collisions and plan data transmission. Furthermore, if the channel is lost due to sensing, communication resources (e.g., frames) are wasted and latency is introduced until the next scheduling cycle.

[0043] To maximize resources and reduce latency, novel methods, devices, and flexible frame structures are proposed to support directional unlicensed access in the Asia-Pacific Hertz (sub-THz) band. Wi-Fi uses CSMA / CA to reserve access and avoid collisions. CSMA / CA provides high spectrum utilization and allows full channel occupancy time utilization, but it is not effective, or at least not very good, for directional access because beamforming requires pre-coordination and synchronization between the transmitter and receiver. Sixty gigahertz (60 GHz) Wi-Gig uses scheduled access and a fixed frame length, which allows users to synchronize to the access point (AP) and perform beam scanning. However, Wi-Gig has only one scheduling period per frame (i.e., a beacon period typically >100 ms), which can lead to high latency and insufficient medium access utilization if new data arrives or if channel congestion is sensed during the transmission phase. Long Term Evolution (LTE) radio systems and NR unlicensed systems use scheduled access combined with Clear Channel Assessment (CCA) before each transmission, which allows for low-latency transmission and flexible resource allocation. However, these systems require CCA and permission in each time slot, as well as separate resources for channel sensing, which can incur additional overhead.

[0044] According to certain aspects of this disclosure, various methods can be considered to effectively support directed unlicensed access in the Asia-Pacific Hertz (sub-THz) band without wasting resources or incurring high latency. In one embodiment, a flexible frame structure for directed unlicensed access is proposed. Scheduled channel access is provided in the unlicensed band. A method is proposed for scheduling multiple UEs using frames with a configurable number of data transmission slots, wherein some of these data transmission slots include a channel sensing period that combines channel detection, CCA, and access reservation mechanisms. The proposed method is designed to allow scheduling operations in the unlicensed spectrum and reduce overhead.

[0045] The method also includes designating a backup scheduled UE, which provides flexibility in the event of a UE-specific CCA failure, while allowing most UEs to sleep and conserve power. A procedure and signaling scheme is also proposed for extending and / or reconfiguring frames when the channel is sensed to be busy or new data arrives in the buffer, which can reduce latency and improve frame utilization for scheduled access. In this way, a solution for low-latency scheduled access is introduced, thereby reducing latency caused by channel sensing and unpredictable traffic patterns.

[0046] In some example implementations, a scheduling channel access frame structure is disclosed. Figure 4This is an example scheduling channel access frame structure for scheduling directed unlicensed access, based on an example implementation. Channel access is organized within a frame. In one implementation, the frame duration is selected to match the maximum channel occupancy time (COT) allowed by applicable standards or regulations. For the sake of example, in some example implementations, the maximum COT may be five milliseconds (5ms), and in other example implementations, the maximum COT may be 10ms. However, these are merely examples, and other durations may be selected. Choosing a frame duration to match the maximum COT simplifies access reservation due to COT sharing, and / or reduces overhead when only a small number of UEs or transmission directions are used during the frame. In one implementation, as... Figure 4 As shown, each frame includes: (1) a beacon and beamforming period; (2) an uplink (UL) signaling phase; (3a) a downlink (DL) signaling phase; (3b) a data transmission phase; and (4a,b) one or more additional signaling phases similar to the initial signaling phase. Phases 1 and 2 provide mechanisms for the UE to access the system, establish and maintain beam alignment between the access point (AP) and the UE, and request scheduling via uplink signaling. The UE can transmit to the AP during the UL signaling phase. For example, the UE can notify the AP of its buffer status and how much data it may need. Phases 3a / b and 4a / b are described in further detail below. DL signaling phase

[0047] Figure 5 This is an example scheduling channel access frame structure highlighting the example DL signaling phase and the additional signaling phase according to the example implementation scheme. Reference Figure 5 Specifically referring to the (3a) DL signaling phase, it is assumed that the DL signaling phase is performed omnidirectionally on the AP side to reach all UEs, while the UEs perform beamforming to the AP. Beam alignment achieved in previous phases is not covered here, but is accomplished via known techniques. The DL signaling is configured to deliver information to all UEs, including: the timing and direction of upcoming data transmission slots, and (optionally) the timing of additional signaling and data transmission cycles in the phase (4a) of scheduling channel access frames. For each upcoming data transmission slot, the signaling information specifies the primary UE and zero or more backup scheduled UEs, which remain awake in the event of a failure of the primary UE's idle channel assessment (CCA) so that backup UEs can be scheduled. CCA failure can occur for various reasons, including when the channel is sensed to be busy. This approach allows for flexible allocation and high frame utilization.

[0048] The duration of data transmission slots is selected to roughly match the expected transmission duration of the primary UE's data. Therefore, different transmission slots may have different durations, which also helps to provide flexible allocation. Slots used for transmissions to / from the same UE (e.g., DL+UL slots for the same UE) and slots using the same direction / beam are grouped together. This allows COT sharing and reduces sensing overhead. When slots used for transmissions to / from the same UE and slots using the same direction / beam are grouped together, another CCA is not required. The primary and backup UEs are selected in such a way that different transmission directions / beams must be used for these UEs. This means that even if the primary UE's CCA fails, transmissions to / from the backup UE can still be attempted (if the channel in its direction is sensed as idle). Data transmission phase

[0049] Figure 6 This is an example scheduled channel access frame structure according to an example implementation scheme, highlighting the example data transmission phase. In one implementation scheme, the data transmission period may include CCA, channel sounding, and access reservation.

[0050] Figure 7 This is an example diagram illustrating an example channel sensing cycle according to an example implementation scheme. (Reference) Figure 7 Each data time slot has a channel sensing period, which combines idle and backoff periods (to comply with regulations or standards), a Listen-Before-Speak (LBT) period for CCA (directed transmission), and Request to Transmit (RTS) and Allow to Transmit (CTS) exchanges. In one implementation, directional LBT may need to be performed for ISAH systems in unlicensed frequency bands. For ISAH systems in unlicensed frequency bands, transmission and interference conditions will be highly directional, for example, with strong interference from some directions and low interference from others. Therefore, LBT may have to be performed directionally, where the CCA outcome will depend on the direction of the communicating peer relative to the directional interference source.

[0051] In some example implementations, RTS and CTS switching are used simultaneously for access reservation and channel sounding over the full data transmission bandwidth, thereby allowing controlled use of reduced bandwidth (BW). The reference signal in the RTS message is used as a Listen-Before-Receive measurement to estimate the signal-to-interference-to-noise ratio (SNR) of the DL channel. This estimate is fed back via the CTS message to allow AP-side link adaptation, or to skip Tx in case of excessive interference or poor link conditions.

[0052] Still referencing Figure 7If the CCA for the UE fails (due to LBT and / or LBR), the AP can communicate to the UE that it should listen for the next (additional) DL CCS to obtain further scheduling information (e.g., by short notification using a "short control signaling" exception in the DL RTS or DL ​​CTS slot). Furthermore, the AP can schedule other UEs / transmission directions by selecting another UE from a set of previously signaled keep-alive standby UEs. In one implementation, a channel sensing period can be selectively applied and can be configured to skip the channel sensing period for subsequent slots if the same UE (also used for alternating DL / UL) or communication direction is used, thereby allowing COT sharing and reducing overhead. Additional scheduling phase

[0053] Figure 8 This is an example diagram illustrating an example additional signaling phase according to an example implementation scheme. In some implementations, the additional signaling phase may provide frame extension and reconfiguration. As will be described in more detail below, the additional signaling phase may include additional timing information. This additional timing information may follow the initial time slot timing. For example, during the initial time slot timing, the AP collects the following information: arrival of DL data entering the AP buffer, UL buffer reports from the UE, and idle channel assessment feedback from the UE. Based on the collected information, the AP signals the UE to the additional time slot timing to retransmit (in the event of CCA failure) or to send / receive additional UL / DL data arriving in the buffer. Reference will be made below. Figure 9 Describe the additional signaling in more detail.

[0054] Figure 9 This is an example flowchart 900 illustrating the exchange of information between the AP and the UE during the example additional signaling phase according to an example implementation. The UE may be similar to the UE 110 disclosed herein and have the functionality of that UE. As previously mentioned above regarding Figure 4 Each frame discussed includes: (1) a beacon and beamforming period; and (2) an uplink (UL) signaling phase. In one implementation, the AP and UE may exchange beacon and beamforming (910) and UL signaling (920) information according to known methods. In one implementation, the UL signaling may include a buffer status report from the UE.

[0055] Then, the AP transmits initial DL signaling to the UE (930). The initial DL signaling may include timing for an initial data transmission slot, which includes the primary UE listening for control signals and (potentially) a backup UE. In some implementations, using a backup UE gives the AP the flexibility to select another UE in the event of an LBT failure and allows the remaining UEs to sleep. Additionally, timing for optional, on-demand additional signaling phases may be transmitted from the AP to the UE. As described above, this additional timing information should generally follow the initial slot timing. During the initial slot timing, the AP collects information such as the arrival of DL data into the AP buffer, UL buffer reports from the UE, and idle channel assessment feedback from the UE (940). Based on the collected information, the AP signals the UE to the additional slot timing to repeat transmission (in the event of a CCA failure) or to send / receive additional UL / DL data arriving in the buffer (950).

[0056] By using the methods, apparatus, and flexible frame structures disclosed herein, directional unlicensed access in the Asia-Pacific Hertz band can be achieved without wasting resources and without experiencing high latency. Although the examples in this document are discussed in relation to the Asia-Pacific Hertz band, the benefits of the disclosed examples are not limited to the Asia-Pacific Hertz band but can be utilized in other frequency ranges (particularly higher frequency ranges) and unlicensed spectrum (e.g., millimeter (mm) waves). Example

[0057] In a first embodiment, a method performed by a user equipment (UE) includes: decoding channel access scheduling information from signaling received from an access point (AP), the channel access scheduling information including at least one frame having a configurable number of data transmission slots; and configuring transceiver circuitry to transmit data and idle channel assessment (CCA) information to the AP, wherein the data and CCA information are transmitted in one or more data transmission slots selected from the configurable number of data transmission slots based on the channel access scheduling information.

[0058] In the second embodiment, according to the method of the first embodiment, one or more data transmission time slots in the data transmission time slots include a channel sensing period, which combines channel detection, idle channel assessment and access reservation mechanism.

[0059] In the third embodiment, according to the method of the first embodiment, the channel access scheduling information includes scheduling information for directed access in unlicensed spectrum.

[0060] In the fourth embodiment, according to the method of the first embodiment, the duration of the frame is selected to match the maximum allowed channel occupancy time (COT).

[0061] In the fifth embodiment, according to the method of the first embodiment, the frame includes a downlink signaling phase, a data transmission phase, an additional scheduling phase, and an additional data transmission phase.

[0062] In the sixth embodiment, according to the method of the fifth embodiment, the channel access scheduling information includes initial downlink signaling information to be included in the downlink signaling phase, and the downlink signaling information includes information about the timing and direction of the upcoming data transmission slot.

[0063] In the seventh embodiment, according to the method of the sixth embodiment, the downlink signaling information further includes timing information for the additional scheduling phase.

[0064] In the eighth embodiment, according to the method of the seventh embodiment, the downlink signaling information further includes information for designating the UE as a primary UE or a backup UE during the frame duration, and when the UE is designated as a backup UE, timing information is provided to the UE to know when it is available in the additional scheduling phase.

[0065] In the ninth embodiment, according to the method of the sixth embodiment, the duration of one or more data transmission slots in the data transmission slots is selected to match the expected transmission duration of the primary UE's data, such that different transmission slots can have different durations.

[0066] In the tenth embodiment, according to the method of the sixth embodiment, data transmission time slots for transmissions to / from the same UE and data transmission time slots using the same direction / beam are grouped together.

[0067] In the eleventh embodiment, the method described in the tenth embodiment is performed, wherein only a single initial free channel assessment needs to be performed.

[0068] In the twelfth embodiment, according to the method of the first embodiment, each data transmission slot in the data transmission slot has a channel sensing period, which combines an idle and backoff period, a directed listen-before-tell (LBT) period for CCA, and a period for request to transmit (RTS) and allow to transmit (CTS) message exchange.

[0069] In the thirteenth embodiment, the method described in the twelfth embodiment is used, wherein RTS and CTS message exchange are used simultaneously to perform access reservation and channel probing over the full data transmission bandwidth.

[0070] In the fourteenth embodiment, according to the method of the thirteenth embodiment, the reference signal in the RTS message is used as a listen-before-receive measurement to estimate the quality metric, which is fed back to the AP via the CTS message to allow AP-side link adaptation.

[0071] In the fifteenth embodiment, according to the method of the fourteenth embodiment, the channel access scheduling information further includes timing information in the event of a CCA failure for the UE, to notify the UE that the UE should listen for further scheduling information in the time slot used for DL ​​RTS or DL ​​CTS.

[0072] In the sixteenth embodiment, according to the method of the twelfth embodiment, the channel access scheduling information further includes an indication for selectively applying a channel sensing period and skipping the channel sensing period if the transmission is to / from the same UE and / or the transmission is using the same direction / beam.

[0073] In the seventeenth embodiment, according to the method of the fifth embodiment, the channel access scheduling information includes downlink signaling information to be included in the downlink signaling phase, the downlink signaling information including: initial timing information for the initial data transmission time slot; and additional timing information for the data transmission time slot in the additional signaling phase.

[0074] In the eighteenth embodiment, according to the method of the seventeenth embodiment, the processing circuitry is configured to configure the transceiver circuitry to send an uplink buffer report to the AP during the initial data transmission time slot, and to send CCA evaluation feedback to the AP.

[0075] In the nineteenth embodiment, according to the method of the eighteenth embodiment, the channel access scheduling information further includes information for notifying the UE whether the UE is a primary UE or a standby UE during the frame duration, and when the UE is designated as a standby UE, timing information is provided for the UE to know when it is available in the additional scheduling phase; and when the UE is a primary UE and the CCA for the UE fails, the downlink signaling information is configured to instruct the UE to retry data transmission during the data transmission slot in the additional signaling phase.

[0076] In the twentieth embodiment, according to the method of the eighteenth embodiment, the channel access scheduling information further includes instructions for instructing the UE to transmit and / or receive additional UL and / or DL ​​data during the data transmission time slot in the additional signaling phase.

[0077] In the twenty-first embodiment, a processor is configured to perform any of the methods described according to the first to the twentieth embodiments.

[0078] In the twenty-second embodiment, a user equipment (UE) includes: a transceiver configured to communicate with an access point (AP); and a processor communicatively coupled to the transceiver and configured to perform any of the methods described in the first to the twentieth embodiments.

[0079] In the twenty-third embodiment, a method performed by an access point (AP) includes: configuring transceiver circuitry to transmit channel access scheduling information to one or more user equipments (UEs) among a plurality of user equipments (UEs), the channel access scheduling information including at least one frame having a configurable number of data transmission slots; and decoding data and idle channel assessment (CCA) information from signaling received from one or more of the plurality of UEs, wherein the data and CCA information are transmitted in one or more data transmission slots selected from the configurable number of data transmission slots based on the channel access scheduling information.

[0080] In the twenty-fourth embodiment, according to the method of the twenty-third embodiment, one or more data transmission time slots in the data transmission time slots include a channel sensing period, which combines channel detection, idle channel assessment and access reservation mechanism.

[0081] In the twenty-fifth embodiment, according to the method of the twenty-third embodiment, the channel access scheduling information includes scheduling information for directed access in unlicensed spectrum.

[0082] In the twenty-sixth embodiment, according to the method of the twenty-third embodiment, the duration of the frame is selected to match the maximum allowed channel occupancy time (COT).

[0083] In the twenty-seventh embodiment, according to the method of the twenty-third embodiment, the frame includes a downlink signaling phase, a data transmission phase, and an additional scheduling phase.

[0084] In the twenty-eighth embodiment, according to the method of the twenty-seventh embodiment, the channel access scheduling information includes initial downlink signaling information to be included in the downlink signaling phase, and the downlink signaling information includes information about the timing and direction of the upcoming data transmission slot.

[0085] In the twenty-ninth embodiment, according to the method described in the twenty-eighth embodiment, the downlink signaling information further includes timing information for the additional scheduling phase.

[0086] In the thirtieth embodiment, according to the method of the twenty-ninth embodiment, channel access scheduling information is omnidirectionally sent to two or more UEs among a plurality of UEs for each data transmission time slot, and the downlink signaling information further includes information for designating one of the plurality of UEs as the primary UE for the frame duration and designating one or more other UEs among the plurality of UEs as the standby UE for the frame duration, and when a UE is designated as a standby UE, timing information of the additional signaling phase is provided to the standby UE to know when it is available in the additional scheduling phase.

[0087] In the thirty-first embodiment, according to the method of the thirty-first embodiment, the duration of one or more data transmission slots in the data transmission slots is selected to match the expected transmission duration of the primary UE's data, such that different transmission slots can have different durations.

[0088] In the thirty-second embodiment, according to the method of the thirty-first embodiment, data transmission time slots for transmissions to / from the same UE and data transmission time slots using the same direction / beam are grouped together.

[0089] In the thirty-third embodiment, the method described in the thirty-second embodiment is performed, wherein only a single initial free channel assessment needs to be performed.

[0090] In the thirty-fourth embodiment, according to the method described in the thirty-first embodiment, the channel access scheduling information is configured to select the primary UE and the backup UE in such a way that different transmission directions / beams are used for the primary UE and the backup UE, so that in the event of a failure of CCA for the primary UE, as long as the channel is sensed to be idle in the direction of the backup UE, transmission to / from the backup UE can still be attempted.

[0091] In the thirty-fifth embodiment, according to the method of the twenty-third embodiment, each data transmission slot in the data transmission slot has a channel sensing period, which combines an idle and backoff period, a directed listen-before-tell (LBT) period for CCA, and a period for request-to-transmit (RTS) and allow-to-transmit (CTS) message exchange.

[0092] In the thirty-sixth embodiment, the method described in the thirty-fifth embodiment is used, wherein RTS and CTS message exchange are used simultaneously to perform access reservation and channel probing over the full data transmission bandwidth.

[0093] In the thirty-seventh embodiment, according to the method of the thirty-sixth embodiment, the reference signal in the RTS message is used as a listen-before-receive measurement to estimate the DL channel signal-to-interference-plus-noise ratio (SINR), which is fed back to the transmitter via the CTS message to allow transmitter-side link adaptation.

[0094] In the thirty-eighth embodiment, according to the method of the thirty-seventh embodiment, in the event of a failure of CCA for the UE, the channel access scheduling information further includes timing information to notify the UE that the UE should listen for further scheduling information in the time slot used for DL ​​RTS or DL ​​CTS.

[0095] In the thirty-ninth embodiment, according to the method of the thirty-tenth embodiment, in the event of a failure of CCA for the UE, the channel access scheduling information is further configured to schedule other UEs or provide other transmission directions by designating a UE from a backup UE to perform data transmission.

[0096] In the fortieth embodiment, according to the method of the thirty-fifth embodiment, the channel access scheduling information further includes an indication for selectively applying a channel sensing period and skipping the channel sensing period if the transmission is to / from the same UE and / or the transmission is using the same direction / beam.

[0097] In the forty-first embodiment, according to the method of the twenty-eighth embodiment, the channel access scheduling information includes downlink signaling information to be included in the downlink signaling phase, the downlink signaling information including: initial timing information for the initial data transmission time slot; and additional timing information for the data transmission time slot in the additional signaling phase.

[0098] In the forty-second embodiment, according to the method of the forty-first embodiment, the processing circuit is configured to: receive downlink data to be sent to the UE during the initial data transmission time slot; receive an uplink buffer report from the UE; and receive CCA evaluation feedback from the UE.

[0099] In the forty-third embodiment, according to the method of the forty-second embodiment, the channel access scheduling information further includes information for notifying the UE whether the UE is a primary UE or a standby UE during the frame duration, and when the UE is designated as a standby UE, timing information is provided for the UE to know when it is available in the additional scheduling phase; and when the UE is a primary UE and the CCA for the UE fails, the downlink signaling information is configured to instruct the UE to initiate a new CCA procedure, and to retry data transmission during the data transmission slot in the additional signaling phase.

[0100] In the forty-fourth embodiment, according to the method of the forty-second embodiment, the channel access scheduling information further includes instructions for instructing the UE to transmit and / or receive additional UL and / or DL ​​data during the data transmission time slot in the additional signaling phase.

[0101] In the forty-fifth embodiment, a processor is configured to perform any of the methods described according to the twenty-third to forty-fourth embodiments.

[0102] In the forty-sixth embodiment, an access point (AP) includes: a transceiver configured to communicate with a user equipment (UE); and a processor communicatively coupled to the transceiver and configured to perform any of the methods described according to the twenty-third to forty-fourth embodiments.

[0103] Those skilled in the art will understand that the example embodiments described above can be implemented with any suitable software or hardware configuration or combination thereof. Example hardware platforms for implementing the example embodiments may include, for example, Intel x86-based platforms with compatible operating systems, Windows OS, Mac platforms and MAC OS, and mobile devices with operating systems such as iOS and Android. The example embodiments described above can be embodied as programs containing lines of code stored on a non-transitory computer-readable storage medium, which, when compiled, can be executed on a processor or microprocessor.

[0104] In some implementations, a non-transitory computer-readable storage medium (e.g., a non-transitory memory element) may be configured to store program instructions and / or data, wherein if these program instructions are executed by a computer system, the computer system performs a method, such as any method implementation of the method implementations described herein, or any combination of method implementations described herein, or any subset of any method implementations described herein, or any combination of such subsets.

[0105] In some implementations, the device (e.g., UE) may be configured to include a processor (or a set of processors) and a memory medium (or memory element), wherein the memory medium stores program instructions, and the processor is configured to read from and execute the program instructions from the memory medium, wherein the program instructions are executable to implement any method implementation (or any combination of method implementations described herein, or any subset of any method implementations described herein, or any combination of such subsets) of the various method implementations described herein. The device may be implemented in any of the various forms.

[0106] Embodiments of the present invention can be implemented in any of a variety of forms. For example, in some embodiments, the invention may be implemented as a computer-implemented method, a computer-readable storage medium, or a computer system. In other embodiments, the invention may be implemented using one or more custom-designed hardware devices such as ASICs. In still other embodiments, the invention may be implemented using one or more programmable hardware elements such as FPGAs.

[0107] Although this application describes various embodiments that have different features in various combinations, those skilled in the art will understand that any feature of one embodiment can be combined with features of other embodiments in any way that is not expressly denied or that is not functionally or logically inconsistent with the operation of the device or the specified function of the disclosed embodiment.

[0108] As is widely recognized, the use of personally identifiable information should comply with privacy policies and measures that are generally accepted to meet or exceed industry or governmental requirements for protecting user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of authorized use should be clearly explained to users.

[0109] It will be apparent to those skilled in the art that various modifications can be made to this disclosure without departing from its spirit or scope. Therefore, this disclosure is intended to cover modifications and variations thereof, provided they fall within the scope of the appended claims and their equivalents.

Claims

1. A system comprising: User equipment (UE), the user equipment (UE) is configured to: Receive channel access scheduling information, the channel access scheduling information including at least one frame having a configurable number of data transmission time slots, wherein the frame includes a downlink signaling phase, a data transmission phase, an additional scheduling phase, and an additional data transmission phase; and Transmit data and idle channel assessment (CCA) information, wherein the data and the CCA information are transmitted in one or more data transmission slots selected from the configurable number of data transmission slots based on the channel access scheduling information; as well as Access point (AP), the access point (AP) is configured as follows: Send the channel access scheduling information to the UE; as well as The data and the free channel assessment (CCA) information are received from the UE.

2. An apparatus for a user equipment (UE), the apparatus comprising processing circuitry configured to: Decode channel access scheduling information from signaling received from the access point (AP), the channel access scheduling information including at least one frame having a configurable number of data transmission slots; and The transceiver circuitry is configured to send data and idle channel assessment (CCA) information to the AP, wherein the data and the CCA information are sent in one or more data transmission slots selected from the configurable number of data transmission slots based on the channel access scheduling information.

3. The apparatus of claim 2, wherein one or more of the data transmission time slots include a channel sensing period, the channel sensing period incorporating channel detection, idle channel assessment and access reservation mechanisms.

4. The apparatus of claim 2, wherein the channel access scheduling information includes scheduling information for directed access in unlicensed spectrum.

5. The apparatus of claim 2, wherein the duration of the frame is selected to match the maximum allowed channel occupancy time (COT).

6. The apparatus of claim 2, wherein the frame includes a downlink signaling phase, a data transmission phase, an additional scheduling phase, and an additional data transmission phase.

7. The apparatus of claim 6, wherein the channel access scheduling information includes initial downlink signaling information to be included in the downlink signaling phase, and wherein the downlink signaling information includes information about the timing and direction of the upcoming data transmission slot.

8. The apparatus of claim 7, wherein the downlink signaling information further includes timing information for the additional scheduling phase.

9. The apparatus of claim 8, wherein the downlink signaling information further includes information for designating the UE as a primary UE or a backup UE during the frame duration, and in the case that the UE is designated as a backup UE, the timing information is provided to the UE to know when it is available in the additional scheduling phase.

10. The apparatus of claim 7, wherein the duration of one or more data transmission slots in the data transmission slots is selected to match the expected transmission duration of the data of the primary UE, such that different transmission slots can have different durations.

11. The apparatus of claim 7, wherein the data transmission time slots for transmissions to / from the same UE and transmissions using the same direction / beam are grouped together.

12. The apparatus of claim 11, wherein only a single initial free channel assessment needs to be performed.

13. The apparatus of claim 2, wherein each data transmission slot in the data transmission slot has a channel sensing period, the channel sensing period combining an idle and backoff period, a directed listen-before-tell (LBT) period for CCA, and a period for request-to-transmit (RTS) and allow-to-transmit (CTS) message exchange.

14. The apparatus of claim 13, wherein the RTS and CTS message exchange are used simultaneously to perform access reservation and channel probing over the full data transmission bandwidth.

15. The apparatus of claim 14, wherein the reference signal in the RTS message is used as a listen-before-receive measurement to estimate a quality metric, the quality metric being fed back to the AP via the CTS message to allow AP-side link adaptation.

16. The apparatus of claim 15, wherein in the event of a CCA failure for the UE, the channel access scheduling information further includes timing information to notify the UE that the UE should listen for further scheduling information in a time slot used for DL ​​RTS or DL ​​CTS.

17. The apparatus of claim 13, wherein the channel access scheduling information further includes an indication for selectively applying the channel sensing period and skipping the channel sensing period if the transmission is to / from the same UE and / or the transmission is using the same direction / beam.

18. The apparatus of claim 6, wherein the channel access scheduling information includes downlink signaling information to be included in the downlink signaling phase, the downlink signaling information including: Initial timing information used for the initial data transmission slot; as well as Additional timing information used for data transmission slots in the additional signaling phase.

19. The apparatus of claim 18, wherein the processing circuitry is configured to configure the transceiver circuitry to send an uplink buffer report to the AP and CCA evaluation feedback to the AP during the initial data transmission time slot.

20. An apparatus for an access point (AP), the apparatus comprising processing circuitry configured to: The transceiver circuitry is configured to transmit channel access scheduling information to one or more user equipments (UEs) among a plurality of user equipments (UEs), the channel access scheduling information comprising at least one frame having a configurable number of data transmission slots; and Data and idle channel assessment (CCA) information are decoded from signaling received from one or more of the plurality of UEs, wherein the data and the CCA information are transmitted in one or more data transmission slots selected from the configurable number of data transmission slots based on the channel access scheduling information.

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