Resource selection for sidelink communication on unlicensed tape (SL-U)

Abstract

Some aspects of this description relate to Mode 2 resource selection techniques for sidelink communication on unlicensed bands (SL-U) based on a CCA operation. A transmitting UE performs the CCA operation and then selects resources using a Mode 2 acquisition and resource selection procedure. The acquisition algorithm begins by identifying potential candidate resources within a selection window. In some aspects, the selection window is limited by an expected CCA time for a Type 1 CCA operation, thus restricting the potential candidate resources to time windows after the expected completion time of the Type 1 CCA operation. This can improve the transmission success rate of the SL-U transmission because fewer transmission errors from incomplete CCA operations would occur.

Description

AREA

[0001] This disclosure relates to wireless communication networks, including techniques for sidelink communication on unlicensed bands. BACKGROUND

[0002] The increasing use of mobile applications has led to a strong emphasis on developing wireless systems capable of transmitting large amounts of data at high speeds. Sidelink communication (SL communication) can be used to facilitate direct communication between devices, bypassing and relieving the base station, and enabling rapid data exchange over short periods. Solutions for efficiency and reliability are constantly being further developed, incorporating enhancements and new features. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] The present disclosure is made easily understandable and accessible by the detailed description and accompanying figures of the drawings. Identical reference numbers may denote identical features and structural elements. Figures and corresponding descriptions are provided as non-exhaustive examples of aspects, implementations, etc., of the present disclosure, and references to "one" aspect, implementation, etc., do not necessarily refer to the same aspect, implementation, etc., and may mean at least one, one, one, one, or more, etc. Fig. Figure 1 is a block diagram illustrating a variety of user devices or user facilities (UEs) configured to perform Sidelink communication on unlicensed tapes (SL-U) according to some aspects of this description. Fig. Figure 2 is a schematic diagram illustrating the timing of resource selection for SL-U according to some aspects of the present description. Fig. Figure 3 is a schematic diagram illustrating the timing of resource selection based on a Clear Channel Assessment (CCA) for SL-U operations according to some aspects of the present description. Fig. Figure 4 is a logical flowchart illustrating a process for selecting and excluding resources based on a CCA operation for SL-U according to some aspects of the present description. Fig. Figure 5 is a schematic diagram illustrating the selection and exclusion of resources based on a CCA process for SL-U according to some aspects of the present description. Fig. Figure 6 is a process flow diagram illustrating a process for a sending UE to perform sidelink communication on unlicensed tapes (SL-U) according to some aspects of the present description. Fig. Figure 7 is a logical flowchart illustrating a process for a sending UE to receive shared channel occupancy time (COT) information and select resources for SL-U according to some aspects of the present description. Fig. Figure 8 is a schematic diagram illustrating the timing of resource selection for SL-U according to some aspects of the present description. Fig. Figure 9 is a process flow diagram illustrating a process for a sending UE to perform sidelink communication on unlicensed tapes (SL-U) using a shared COT according to some aspects of the present description. Fig. Figure 10 is a block diagram illustrating a device that can be used to perform resource selection for SL-U using a CCA operation according to some aspects of the present disclosure. Fig. Figure 11 is a block diagram illustrating a baseband switching logic that can be used to perform resource selection for SL-U using a CCA operation according to some aspects of the present description. DETAILED DESCRIPTION

[0004] The following detailed description refers to the accompanying drawings. Identical reference numbers in different drawings may denote the same or similar features, elements, processes, etc. Furthermore, the present disclosure is not limited to the following description, as other implementations may be used and structural or logical modifications may be made without altering the scope of this disclosure.

[0005] Wireless communication networks can include user devices or user equipment (UEs) capable of wirelessly communicating with base stations and other network nodes, as well as direct communication between UEs using sidelink signaling. For sidelink communication between UEs, resource allocation can be performed using either Mode 1 or Mode 2. In Mode 1, the network (e.g., a base station) allocates resources and notifies the UEs of the resource allocation via the Uu operation, and the UEs send / receive sidelink signals using the allocated resources. In Mode 2, a transmitting UE participating in sidelink communication can autonomously allocate resources and communicate data to one or more other UEs using the allocated resources.Sidelink resources can be determined based on a collection and selection process, supported by the announcement of resource reservations by other teaching units (TUs). Resources can be selected and / or reserved from Sidelink resource pools that can be shared by multiple Sidelink TUs.

[0006] Furthermore, sidelink transmissions can utilize unlicensed frequency bands for standalone operation or licensed access as supplementary spectra to provide increased system capacity and transmission flexibility. To operate in the unlicensed frequency bands, UEs can perform one or more Clear Channel Assessment (CCA) operations to determine if one or more channels in the unlicensed spectrum are unavailable or otherwise occupied before transmitting in that spectrum. The CCA operations can be performed according to a Listen-Before-Talk (LBT) protocol or other channel occupancy detection methods. For example, a transmitting UE might wait for a delay period to detect other potential transmission activity on a channel before declaring the channel available and then wait for a backoff period before transmitting.The CCA processes help coordinate spectrum usage across multiple devices and even different radio access technologies. However, the time required for the CCA processes, such as the aforementioned delay duration and backoff period, negatively impacts the successful selection of sidelink resources and can therefore delay the transmission of sidelink data. For example, the time slot for the resources selected by the sending UE might arrive before the CCA processes are complete, resulting in an error when transmitting sidelink data using the selected resources.

[0007] Accordingly, some aspects of this description relate to Mode 2 resource selection techniques for sidelink communication on unlicensed bands (SL-U) based on a CCA operation. A transmitting UE performs the CCA operation and then selects resources using a Mode 2 acquisition and resource selection procedure. The acquisition algorithm begins by identifying potential candidate resources within a selection window. In some aspects, the selection window is limited by an expected CCA time for a Type 1 CCA operation, thus restricting the potential candidate resources to time windows after the expected completion time of the Type 1 CCA operation. This can improve the transmission success rate of the SL-U transmission because fewer transmission errors from incomplete CCA operations would occur.Additionally or alternatively, the selection window is limited by a COT duration of a shared COT, initiated by an initiating UE when resources are selected or reselected for transfer to the initiating UE using the shared COT. In some further aspects, the sending UE receives a consistent LBT error indication from a higher layer and accordingly excludes the relevant resources to form a set of adapted (e.g., remaining) candidate resources. This can improve the efficiency of resource selection and subsequent SL-U transfer, as the occupied channel is excluded without requiring multiple separate CCA operations. Additional aspects and details of the disclosure are further described below with reference to the figures.

[0008] Fig. Figure 1 is a block diagram that configures the systems and devices of an example network 100, including a variety of UEs, such as UE 110-1, UE 110-2, UE 110-3, UE 110-4, etc. (hereinafter also referred to as UEs 110), to perform sidelink communication over unlicensed bands, as well as related procedures and operations according to some aspects of this description. The UEs 110 can also communicate with and connect to a Radio Access Network (RAN) node, such as a base station 111 (e.g., be communicatively coupled to it). UE 110-1 is shown as the sending UE with sidelink data to be transmitted to a receiving UE, such as UE 110-2. In the case of resource allocation in mode 2, the sending UE 110-1 autonomously decides on the resources to be used for the sidelink transmission based on a detection and resource selection procedure 106, as described below and also in connection with Fig. 2 is described in more detail. The acquisition and resource selection procedure 106 can be supported by resource reservations 102 received from other UEs 110-2, 110-3, 110-4, etc. The resource reservations 102 can be sent by the other UEs 110-2, 110-3, 110-4 as part of a first-stage SCI transmitted over a physical sidelink control channel (PSCCH). The resources can be reserved and / or selected from sidelink resource pools that can be shared by multiple UEs 110.

[0009] The UEs 110 can communicate with each other over a licensed medium (also referred to as "licensed spectrum" and / or "licensed band"), an unlicensed medium (also referred to as "unlicensed spectrum" and / or "unlicensed band"), or a combination thereof. A licensed spectrum may correspond to channels or frequency bands selected, reserved, regulated, etc., for certain types of wireless activity (e.g., wireless telecommunications network activity), while an unlicensed spectrum may correspond to one or more frequency bands that are not restricted for certain types of wireless activity. Whether a particular frequency band corresponds to a licensed or unlicensed medium may depend on one or more factors, such as frequency allocations made by a public sector organization (e.g., a government agency, regulatory body, etc.).) are determined, or frequency allocations determined by a private sector organization involved in the development of standards and protocols for wireless communication, etc.

[0010] To operate in the unlicensed spectrum, UEs 110 and the base station 111 can operate in standalone mode or using the Licensed Assisted Access (LAA), eLAA, or feLAA mechanism. In these implementations, the transmitting UEs 110-1 can perform a CCA operation 104, such as various types of media capture or carrier capture operations, to determine whether one or more channels in the unlicensed spectrum are unavailable or otherwise occupied before transmission in the unlicensed spectrum. The media / carrier capture operations can be performed according to a Listen-Before-Talk (LBT) protocol.

[0011] As shown in Action 112, the sending UE 110-1 then transmits the sidelink data to the receiving UE 110-2 over the selected resources. The sidelink data is transmitted as transport blocks (TBs) on a shared physical sidelink channel (PSSCH). A TB is associated with the SCI. The SCI specifies the resources used by the PSSCH that the associated TB carries and other information for decoding the TB. The SCI can be transmitted in the same slot as the sidelink data and consists of two stages. A first-stage SCI is transmitted on a physical sidelink control channel (PSCCH), while a second-stage SCI is transmitted on the corresponding PSSCH that carries the TB. The second-stage SCI allows for a flexible SCI design to support unicast, groupcast, and broadcast transmissions. By splitting the SCI into two stages, other UEs (e.g., UEs 110-3, 110-4) can only access the first stage.Stage SCI decodes the channel detection data to determine the reserved resources of the transmitting UE 110-1. Stage 2 SCI, on the other hand, provides additional control information required for transmission to the receiving UE 110-2.

[0012] As shown by Act 114, in some respects, the sending UE 110-1 can receive shared COT information initiated by another UE, such as UE 110-2 as the initiating UE of a shared COT, which may be shared by UE 110-1, and / or other COT-sharing candidate UEs, such as UEs 110-3 and 110-4. The shared COT information is transmitted from UE 110-2 to UE 110-1 along with a data payload. The shared COT information specifies parameters of the shared COT, such as the duration of the COT, the UE identity of the initiating UE, and a Channel Access Priority Class (CAPC) value for granting the COT (CAPC-COT). The shared COT information can be transferred to a 1st level SCI on a PSCCH and sent to multiple UEs or via group casting, such as UEs 110-1, 110-3, 110-4.The data payload is carried on a PSSCH and can be transferred to the UE 110-1 in the same slot as the PSCCH, which carries the shared COT information.

[0013] As indicated by an initial indicator 1.1 and further in connection with Fig. Figure 2 and other figures herein indicate that, in some respects, an expected time period for the execution of the CCA operation 104 is used to limit a resource selection window for the acquisition and resource selection procedure 106. In particular, a resource selection window start time takes into account a minimum expected period for the CCA operation 104 (“T CCA_min “), while an end time of the resource selection window represents a maximum expected time span for CCA operation 104 (“T CCA_max “) taken into account. T CCA_min and T CCA_maxare calculated based on a Channel Access Priority Class (CAPC) value of the sidelink data to be transmitted and a current conflict window size ("CW_p") of CCA operation 104. In some further aspects, CCA operation 104 includes determining a channel occupancy rate Roc, and T CCA_min and T CCA_max further calculations are based on the channel occupancy rate.

[0014] As indicated by a second indicator 1.2 and further in connection with Fig. As discussed in Figure 3 and other figures herein, in some aspects a channel allocation condition determined by the CCA operation 104 is used to exclude resources during the acquisition and resource selection procedure 106. In particular, information on resource blocks with consistent LBT error is acquired and provided by a MAC layer of a physical layer of the transmitting UE 110-1, and the resource block set is selected from an initial set of candidate resources “S A " excluded.

[0015] As shown by a third indicator 1.3 and further in connection with Fig. As discussed in Figure 2 and other figures herein, in some respects resource selection is performed based on the parameters of the COT when the sending UE 110-1 shares the COT with the receiving UE 110-2. For example, the resource selection window (e.g., selection window 202 in Fig. 2) limited by a COT duration so that the SL transfer can be transferred in time and completed during the COT.

[0016] Additionally, the Base Station 111 can be configured for wireless communication with the UEs 110 and can provide the UEs 110 with resource allocation configurations in 2-Sidelink mode, as shown in Act 116. These configurations are intended to optimize the use of available resources and ensure that the UEs 110 can communicate with each other reliably and efficiently. For example, the Base Station 111 can configure the size and number of resource blocks available to the UEs 110. This can include reserving specific resource blocks for special use cases, such as emergency services or specific types of communication.

[0017] The Base Station 111 can also configure the sidelink channel, including selecting the frequency band, bandwidth, and modulation scheme used for sidelink communication. The Base Station 111 can also configure the maximum transmission power that the UEs 110 can use for sidelink communication. This helps to avoid interference from other devices and ensures efficient network operation.

[0018] The UEs 110 can include types of mobile or non-mobile computing devices, such as consumer electronics devices, mobile phones, smartphones, feature phones, tablet computers, portable computing devices, personal digital assistants (PDAs), pagers, wireless handsets, desktop computers, laptop computers, in-vehicle infotainment (IVI) systems, in-car entertainment (ICE) systems, instrument clusters (ICs), head-up display (HUD) systems, on-board diagnostic (OBD) systems, mobile instrument panel equipment (DME), mobile data terminals (MDTs), electronic engine management systems (EEMS), electronic / engine control units (ECUs), electronic / engine control modules (ECMs), embedded systems, microcontrollers, control modules, engine management systems (EMS), networked or "smart" devices, machine-type communication (MTC) devices, and machine-to-machine (M2M) devices. (M2M),Internet of Things devices (IoT devices) and / or the like.

[0019] The systems and devices of Exemplary Network 100 can operate according to one or more communication standards, such as 4th Generation (4G) (e.g., Long Term Evolution (LTE)), 5th Generation (5G) (e.g., New Radio (NR)), and / or other communication standards of the Partnership Project 3rd Generation (3GPP). Additionally or alternatively, one or more of the systems and devices of Exemplary Network 100 can operate according to other communication standards and protocols discussed herein, including future versions or generations of 3GPP standards (e.g., 6th Generation (6G) standards, etc.), Institute of Electrical and Electronics Engineers (IEEE) standards (e.g., Wireless Metropolitan Area Network (WMAN), Worldwide Interoperability for Microwave Access (WiMAX), etc.), and more.

[0020] In some respects, the RAN node, acting as Base Station 111, can be a Next-Generation (NG) RAN or a 5G RAN, an Evolved UMTS Terrestrial RAN (E-UTRAN), or a legacy RAN, such as a UTRAN or GERAN. As used herein, the term "NG-RAN" or similar can refer to a RAN node operating in an NR or 5G system, and the term "E-UTRAN" or similar can refer to a RAN node operating in an LTE or 4G system. The RAN node can also be connected to a Core Network (CN) via an NG interface. The CN can comprise a variety of network elements configured to provide various data and telecommunications services to customers / subscribers (e.g., users of UEs 110) connected to the CN via the RAN.

[0021] Fig. Figure 2 is a schematic diagram 200 illustrating the resource selection for sidelink data transmission over unlicensed tapes according to some aspects of the present description. As described above in connection with the acquisition and resource selection procedure 106, in the Mode 2 resource allocation, a sending UE (e.g., the sending UE 110-1 in Fig. 1) Autonomously allocate resources for transmission and retransmission during sidelink communication when the resources are not in use by other UEs with higher-priority traffic, as determined by a capture procedure performed within a capture window 201. The sending UE can then select resources within a selection window 202 and occupy them for a reasonable period of time until a re-selection event is triggered.

[0022] The acquisition process begins with the sending UE determining the selection window and all potential candidate resources within selection window 202. The sending UE's selection of resources for (re)transmission is based on the acquisition results obtained during acquisition window 201 for the potential candidate resources within selection window 202. Selection window 202 is defined as being limited to a time frame (n + T1, n + T2), where n is a trigger time for resource allocation, n + T1 is the lower bound of selection window 202, and n + T2 is the upper bound of selection window 202. For example, the trigger time n could be the arrival time of a transport block.There are two processing times (Tproc0 and Tproc1) before and after the trigger time n, which can each refer to the time required in the physical and MAC layers, respectively, for processing an information exchange between the layers and preparing physical sidelink channels. In resource allocation mode 2, the sending UE can perform continuous acquisition. When a resource selection event is triggered at trigger time n in the sending UE, it considers its most recent acquisition results within the acquisition window 201 (e.g., between 1100 ms and 100 ms) prior to trigger time n for resource selection. The sensor results at a wider boundary n - T0 (e.g., 1100 ms) of the acquisition window 201 are useful for identifying the resources reserved by other UEs for periodic traffic, and the acquisition results at a narrower boundary n - T are useful for identifying the resources reserved by other UEs for periodic traffic. proc,0(e.g. 100 ms) of the detection window 201 are particularly useful for non-periodic traffic.

[0023] In some respects, the lower bound n + T1 of the selection window 202 is considered taking into account a minimum expected CCA time T. CCA_min determined so that the resource candidates can be restricted to resource candidates after completion of the CCA process, thus increasing the success rate of the SL-U transfer. As an example, the lower bound n + T1 can be defined as T CCA_min ≤T1≤Tproc,1 + T CCA_min Tproc,1 is the processing time required for resource selection for sidelink transmission and can be specified in slots or in time. For example, Tproc,1 can be equal to 3, 5, 9, or 17 slots for a subcarrier spacing (SCS) of 15, 30, 60, or 120 kHz, respectively. CCA_minIt can be calculated based on a Channel Access Priority Class (CAPC) value of the sidelink data to be transmitted and a current conflict window size ("CW_p") of the CCA operation. In some other respects, a channel occupancy rate Roc is also included in the calculation of T. CCA_min included.

[0024] In some respects, the upper limit n + T2 of the selection window 202 is considered taking into account a maximum expected CCA time T. CCA_max determined so that the resource candidates can be expanded taking into account the time required by the CCA process, thereby increasing the availability and efficiency of resource selection. For example, the upper limit n + T2 can be defined as T 2,min +T CCA_max ≤T2≤T PDB be determined, where T 2min a predefined or preconfigured time parameter for the minimum selection period, and T PDB isThe remaining packet delay budget (PDB) is used to meet latency requirements. For example, T 2min It could be 1, 5, 10, or 20 slots. T 2min can also be defined in time instead of slots. T CCA_max can be calculated based on the CAPC value of the sidelink data to be transmitted and the current conflict window size ("CW_p") of the CCA operation. In some other respects, the channel occupancy rate Roc is also included in the calculation of T. CCA_max included. Further details on the expected CCA times T CCA_min and T CCA_max are subsequently discussed in connection with a diagram of Fig. 3 described.

[0025] Fig. Figure 3 shows a schematic diagram illustrating the timing of resource selection based on a Clear Channel Assessment (CCA) for SL-U operation, according to some aspects of this description. CCA operation helps coordinate spectrum utilization across multiple devices and even different radio access technologies. There are different types of CCA operations for different communication schemes. CCA Type 1 is used to initiate one or more transmissions within the same channel occupancy time (COT), while CCA Type 2 is used for COT sharing and the transmission of discovery bursts. CCA Type 2 includes Type 2A, 2B, or 2C, which are performed depending on the length of a COT gap between transmissions. CCA Type 2A is performed when the COT gap is equal to or greater than 25 µs and is used to transmit the discovery burst.CCA type 2B is performed when the COT gap is equal to or greater than 16 µs but less than 25 µs. CCA type 2C is performed when the COT gap is less than 16 µs.

[0026] If the CCA process is CCA Type 1, the sending UE can, after a delay period T, d Listen for other potential transmission activity on a channel before declaring the channel available and wait for a backoff period before transmitting. An example of a Type 1 CCA operation might include steps shown in Logic Diagram 300: 1) Initialize a backoff counter N with a random value evenly distributed between 0 and the current conflict window size (“CW_p”), as shown by Action 310; 2) Wait until the channel is idle for the delay duration Td (e.g. 16 µs + m*9 µs), as shown by action 320; 3) Determine whether N is equal to 0, as shown by action 330; 4) If N = 0, the sending UE is ready to transmit sidelink data as planned, as shown by action 360; 5) If N > 0, adjust to N = N - 1, as shown by Action 340; and 6) After decrementing the backoff counter N, capture the channel for an additional sampling slot duration (e.g., 9 µs), as shown by action 350. If the duration of the additional sampling slot is idle, proceed to action 330 to determine if N decreases to 0; otherwise, proceed to action 320 to wait for a further delay duration Td until the channel becomes free / inactive.

[0027] The delay duration T d depends on the priority of the data. For example, the delay time T dThe acquisition window consists of a fixed time interval Tf (e.g., 16 µs) and an integer m of multiples of the acquisition slot durations (e.g., m * 9 µs). The number m can be related to the CAPC value of the data to be transmitted. Table 301 shows an example of m values ​​and permissible CW sizes for corresponding CAPC classes. Thus, high-priority traffic (with a smaller CAPC value) acquires the channel for a shorter period Td and can therefore occupy the channel more quickly than low-priority traffic. The backoff counter N is randomly selected by the CCA process between 0 and the current conflict window size ("CW_p") to prevent collisions between multiple transmitters. Without the random backoff, two UEs waiting for the channel to become available would start simultaneously, resulting in a collision. The random backoff significantly reduces the probability of multiple UEs attempting to access the channel at the same time.Furthermore, high-priority traffic (with a smaller CAPC value) uses a smaller conflict window (CW) to access the channel faster, while low-priority traffic uses a larger CW, increasing the likelihood that high-priority traffic will be transmitted before low-priority traffic. The size of the current conflict window, CW_p, is adjusted based on an acknowledgment / non-acknowledgment (ACK / NACK) response. For example, CW_p may be set to its minimum value after receiving a positive ACK / NACK response and may be doubled to its maximum value upon receiving a negative ACK / NACK response. Thus, the channel is used more aggressively for efficiency reasons when transmissions are successful and less aggressively when transmissions fail, in order to reduce collisions with other transmissions.

[0028] Thus, in some respects, the minimum expected CCA time T isCCA_min , as described above, from the delay duration Td and a back-off duration Tb. For example, T CCA_min set to Td + Tb, where Td is 16 µs + m*9 µs. However, the estimated backoff duration Tb depends on the individual transmission conditions. Assuming all capture slots were detected idle during action 350 of the CCA operation type 1, shown in logic diagram 300, the estimated backoff duration Tb is N*9 µs. Thus, T CCA_minThe backoff duration Tb can be set to 16 µs + m*9 µs + N*9 µs. However, in various user scenarios, a more heavily utilized channel would lead to a longer backoff duration Tb, as the channel might be detected as occupied by action 350, thus prolonging CCA operation. Accordingly, in some other respects, the estimation of the expected backoff duration Tb can be improved by including a channel occupancy rate Roc, which indicates the ratio of detection slots considered occupied. As an example, T CCA_min be set to 16 µs + m*9 µs + N*9 µs / (1-Roc).

[0029] In one aspect, a received signal strength indicator (RSSI) measurement is performed for sidelink transmission. The RSSI measurement can be configured or preconfigured by a base station with a channel occupancy threshold (e.g., `channelOccupancyThreshold`) and a measurement window (e.g., `reportInterval`). The configurations can be included as part of the report configuration (e.g., the RRC IE `reportConfig`). The channel occupancy rate (Roc) is defined using the RSSI measurement results. Specifically, the channel occupancy rate (Roc) is defined as the percentage of samples with an RSSI higher than the channel occupancy threshold measured within the measurement window. For example, the channel occupancy rate (Roc) can be a percentage of samples with a received signal power level greater than a configurable threshold (e.g., configured in a range of 0 to -76 dBm) or set to a predefined value (e.g., 1000 dBm).-72 dBm) is pre-configured within a configurable measurement window of, for example, 160 ms.

[0030] In some alternative perspectives, the channel occupancy rate Roc is defined using measurement results from the CCA process. Specifically, the channel occupancy rate Roc is defined as the percentage of acquisition slots identified as occupied within a predefined time window, relative to the total number of acquisition slots. For example, if 9 acquisition slots are identified as occupied within a time window of 20 acquisition slots, the channel occupancy rate Roc is 45%. An acquisition slot can be identified as occupied if a received energy meets a threshold value for at least 4 µs of a 9 µs acquisition slot.

[0031] Similarly, the maximum CCA time T CCA_maxAs described above, it can also be set to Td + Tb, where Td is 16 µs + m*9 µs and Tb is estimated as N*9 µs in some views and as N*9 µs / (1-Roc) in some alternative views. The expected backoff duration Tb can be further extended to the current conflict window CW_p or additionally considered in the channel occupancy rate Roc as CW_p / (1 - Roc), allowing more potentially available candidate resources to be included in the resource selection. Thus, the maximum CCA time T can be CCA_max can be set to 16 µs + m*9 µs + CW_p or 16 µs + m*9 µs + CW_p / (1-Roc).

[0032] Fig. Figure 4 shows a logical flowchart 400 illustrating a process for selecting and eliminating resources based on a CCA operation for SL-U according to some aspects of the present description. As shown by action 410, a selection window is determined and potential candidate resources within the selection window are identified. The determination of the selection window was discussed above in the context of Fig. Described in sections 1 to 3, the selection window, represented by (n + T1, n + T2), is limited by an expected CCA time for a Type 1 CCA operation. This restricts potential candidate resources to the time slots after the expected completion of the Type 1 CCA operation. This improves the transmission success rate of the SL-U transfer.

[0033] As shown by action 420, a data capture window is determined that precedes the selection window. The data capture window is represented by (n - T0, n - T proc,0 ), is used to receive channel occupancy information, such as resource reservations by other UEs. Sensor results at a wider limit n - T0 (e.g., 1100 ms) of the acquisition window are advantageous for identifying the resources reserved by other UEs for periodic traffic, and acquisition results at a narrower limit n - T proc,0 (e.g. 100 ms) of the detection window are particularly useful for non-periodic traffic.

[0034] As shown by actions 430 through 470, resource reservations received from other UEs during the acquisition window are decoded to be excluded from the candidate resources if certain criteria are met. As shown by action 430, the UE receives an initial RSRP threshold. In some views, the initial RSRP threshold is configured or preconfigured on a per-resource-pool basis. In some additional or alternative views, the initial RSRP threshold is based on the priority (prio_TX) of the transmitted data. For example, if the transmitted data has a high priority, a higher initial RSRP threshold can be used. The higher RSRP threshold results in fewer candidate resources being excluded from selection, thus making more suitable candidate resources available.Conversely, a lower initial RSRP threshold can be used if the transmitted data has a low priority.

[0035] As shown by Act 440, the UE receives an initial set of candidate resources “S A “for SL-U transfer. In some aspects, the UE includes resources that are related to the RB set with a consistent LBT error from the initial candidate resources S AOverlap to form a set of matched (e.g., remaining) candidate resources. The RB set with consistent LBT errors is reported to the physical layer by a higher layer (e.g., MAC layer). A consistent LBT error is detected and reported for each RB set by counting LBT error indications for SL-U transmissions from the physical layer to the MAC layer. Subsequently, the MAC layer determines a consistent LBT error when the LBT error indications reach a (pre-)configured threshold. The MAC entity can be configured by RRC with a consistent LBT error correction procedure. RRC configures the parameters used to detect consistent sidelink LBT errors for shared spectrum channel access operation.For example, a maximum LBT failure count (lbt-FailureInstanceMaxCount) and a failure detection timer (e.g., lbt-FailureDetectionTimer) can be configured in a failure recovery configuration (e.g., Ibt-FailureRecoveryConfig) and is used to determine the consistent LBT failure.

[0036] As shown by Action 450, the set of adjusted (e.g., remaining) candidate resources is further filtered to exclude resources if the UE received SCI during the capture window that reserves the resources, and if an RSRP associated with the SCI is greater than the RSRP threshold. In some additional or alternative viewpoints, the initial RSRP threshold is based on a priority prio_RX of SCI received from another UE. For example, if the UE received SCI from another UE (e.g., during the capture window) that reserves high-priority resources, the UE may initially use a lower RSRP threshold. Consequently, high-priority resources are more likely to be excluded from resource selection, thus reducing interference from another UE's high-priority transmission.Alternatively, if the UE has only received SCI from other UEs, it can reserve the resources for low-priority SL-PRS, use a higher initial RSRP threshold, so that the resources are more likely to be considered available candidate resources.

[0037] As shown by Act 460, if the set of adjusted candidate resources is less than a threshold percentage “X” of the initial candidate resources S AThe resource pool is reordered as shown by action 470, and the MAC layer then selects resources from the updated resource pool. As an example of reordering the resource pool, the RSRP threshold is increased by one RSRP adjustment value, and the process is repeated. Alternatively, the adjusted candidate resources are reported to a higher layer (e.g., the MAC layer) for subsequent resource selection and SL-U data transmission, as shown by action 480. The threshold percentage X can be either configured or preconfigured. For example, after excluding reserved resources from the selection window (as shown and described in the context of actions 440 and 450), the MAC layer can select resources from the set of adjusted candidate resources. The selection can be random or based on time, traffic priority, and / or measurement conditions.For example, resources can be randomly selected from 20% of the best resources with a measured RSRP below the (pre-)configured threshold, based on traffic priority. If, after eliminating actions 440 and 450, the remaining resources are less than 20% of all resources in the selection window, the UE relaxes the RSRP threshold (by 3 dB) until it includes at least 20% (or 35%, 50%, depending on traffic priority) of all resources in the resource allocation selection window. The final resource selection occurs in the MAC layer of an UE, which receives a set of unallocated resources from the physical layer.

[0038] Fig. Figure 5 shows a schematic diagram 500 of a resource pool within a selection window, illustrating the selection and exclusion of resources based on a CCA operation for SL-U according to some aspects of the present description. In some aspects, if the UE has information about an RB set with a consistent LBT error, as described above, in connection with action 440 of Fig. If 4 is received, the RB set is excluded from the resource pool. In some cases, the RB set is identified as covering one or more subchannel frequencies and not being limited in time. Thus, multiple time slots of potential candidate resources can be excluded without requiring multiple CCA operations.

[0039] Fig. Figure 6 is a process flow diagram 600 illustrating a process for a sending UE (e.g., the sending UE 110-1 as described throughout the description) to carry out communication on SL-U based on a CCA operation according to some aspects of the present description.

[0040] As shown by Action 610, the sending UE captures resource reservations from other UEs and selects resources for the SL-U transmission. When selecting resources, parameters and conditions of a CCA operation to be performed can be taken into account. From one perspective, as shown by Action 611, determining a selection window considers an expected CCA uptime that the CCA operation may take. As described above, the expected CCA uptime for CCA Type 1 includes a delay period Td and a backoff period Tb. The delay period T ddepends on the priority of the data. For example, the delay time T d The CCA consists of a fixed time interval Tf (e.g., 16 µs) and an integer m of multiples of the capture slot durations (e.g., m * 9 µs). The number m can be related to the CAPC value of the data to be transmitted. The estimated backoff duration Tb depends on the individual transmission conditions. Assuming all capture slots were free during the Type 1 CCA operation, the estimated backoff duration Tb is N * 9 µs, where N is a randomly selected integer between 0 and a current conflict window. Thus, a minimum expected CCA uptime T can be determined. CCA_min, set to 16 µs + m*9 µs + N*9 µs. However, in various user scenarios, a more heavily utilized channel would lead to a longer backoff duration Tb, as the channel might be detected as occupied, thus requiring longer CCA operation. Accordingly, in some other respects, the estimation of the expected backoff duration Tb can be improved by including a channel occupancy rate Roc, which indicates the ratio of acquisition slots considered occupied. As an example, T CCA_min be set to 16 µs + m*9 µs + N*9 µs / (1-Roc). T CCA_minThis can be used to limit a lower bound of the selection window, thus reducing transmission errors due to an incomplete CCA operation. From another perspective, as shown by Action 612, the candidate resource set can be adjusted by excluding candidates based on a consistent LBT error. One or more RB sets with a consistent LBT error are reported to the physical layer by a higher layer (e.g., the MAC layer). A consistent LBT error is detected and reported for each RB set by counting LBT error reports from the physical layer to the MAC layer. Subsequently, the MAC layer determines a consistent LBT error when the LBT error reports reach a (pre-)configured threshold.

[0041] As shown by Action 620, the CCA operation is performed for SL-U. The CCA operation can be a Type 1 CCA to initiate one or more transmissions within the same Channel Occupancy Time (COT). Alternatively or additionally, the CCA operation can include Type 2 CCA, which is used for COT sharing and the transmission of discovery bursts. Type 2 CCA includes Type 2A, 2B, or 2C, which are performed depending on the length of a COT gap between transmissions. Type 2A CCA is performed when the COT gap is equal to or greater than 25 µs and is used to transmit the discovery burst. Type 2B CCA is performed when the COT gap is equal to or greater than 16 µs but less than 25 µs. Type 2C CCA is performed when the COT gap is less than 16 µs.If the CCA operation is a type 1 CCA operation, the sending UE may listen for other potential transmission activity on a channel after a delay period Td before declaring the channel available, and waits for a backoff period Tb before transmitting.

[0042] As shown by action 630, after selecting the resources, the sending UE transmits data to another UE using the selected resources for the SL-U.

[0043] Fig. Figure 7 is a logical flowchart 700 illustrating a process for a sending UE (e.g., the sending UE 110-1 as described throughout the description) to receive common channel occupancy time (COT) information and select resources for SL-U according to some aspects of the present description.

[0044] In action 710, shared channel occupancy time (COT) information is transmitted from UE 110-2, the initiating UE, to the sending UE 110-1. The shared COT information includes information about a shared COT initiated by the initiating UE. In some views, the shared COT information includes one or more COT durations and an UE identity of the initiating UE 110-2. In some views, the shared COT information may also include a priority threshold for using the COT. In some views, the shared COT information is transmitted in a Sidelink Control Information (SCI) format. The shared COT information may be transmitted on a Physical Sidelink Control Channel (PSCCH).In some respects, the shared COT information can be transmitted exclusively between the initializing UE 110-2 and the transmitting UE 110-1 (unicast). In other respects, the initializing UE 110-2 can send the shared COT information for reception by all candidate UEs within its radio range (broadcast), or it can send the shared COT information for reception by a set of receivers that meet certain conditions (group cast).

[0045] In action 720, the SCI, including the shared COT information, can be decoded and sent from a physical layer to a MAC layer of UE 110-1. A determination is then made as to whether UE 110-1 could share the COT based on the shared COT information, for example, by evaluating the availability and priority of MAC-CEs and / or logic channels for UE 110-1 and / or other candidate UEs based on the shared COT information.

[0046] In action 730, a resource for the shared COT transmission is selected or reselected from the sending UE 110-1 to the initiating UE 110-2. A resource selection window for SL-U has a start time and an end time. The end time is no later than the remaining COT duration of the COT or the remaining PDB duration.

[0047] In action 740, data is transferred from UE 110-1 to UE 110-2 using the selected or newly selected resources via the shared COT.

[0048] Fig. Figure 8 shows a schematic diagram 800 of a resource pool within a selection window 202, illustrating a sending UE (e.g., sending UE 110-1 as described throughout this description) to select resources for SL-U transmission using a shared COT according to some aspects of this description. In addition to or as an alternative to various restrictions of the capture window, as already described, in some aspects the selection window 202 may also be bound to a remaining COT duration 804. Therefore, in some aspects the selection window 202 is defined as the minimum of a PDB 803 and the remaining COT duration 804. Thus, the selection window 202 is limited by the remaining COT duration 804 so that the sidelink transmission for the initializing UE can be completed during the remaining COT duration 804.Resource selection can be random or based on time, traffic priority, and / or measurement conditions. For example, resources can be randomly selected from the available candidate resources (e.g., R1, R2, R3, and R4 in the figure). Alternatively, earlier resources (e.g., R1, R2) can be selected over later resources (e.g., R3, R4) to better utilize the shared COT. If the remaining resources after the elimination procedures fall below a threshold, the resource pool can be rearranged as described above.

[0049] Fig. Figure 9 shows a process flow diagram 900 illustrating a process for a sending UE (e.g., the sending UE 110-1 as described throughout the description) to transfer data to SL-U using a shared COT according to some aspects of the present description.

[0050] As shown by Act 910, shared channel occupancy time (COT) information is received from an initiating UE to the sending UE. The shared COT information includes information about a shared COT initiated by the initiating UE. In some views, the shared COT information includes one or more COT durations and a UE identity of the initiating UE. In some views, the shared COT information is transmitted in a Sidelink Control Information (SCI) format. The shared COT information can be transmitted on a Physical Sidelink Control Channel (PSCCH). The shared COT information can be decoded and sent from a physical layer to a MAC layer.A determination is made as to whether the sending UE could use the shared COT based on the shared COT information, for example by evaluating the availability and priority of MAC-CEs and / or logic channels for the sending UE based on the shared COT information.

[0051] As shown by action 920, when it is determined that the sending UE can use the shared COT, a resource for shared COT transfer from the sending UE to the initiating UE is selected or reselected. A resource selection window is determined with an end time that is no later than the remaining COT duration of the COT or the remaining PDB duration.

[0052] As shown by action 930, data is transferred from the sending UE to the initiating UE using the selected or newly selected resources via the shared COT.

[0053] Fig. Figure 10 is a diagram of an example of components of a device 1000 according to one or more implementations described herein. The device 1000 or its components may also be or be included in a UE such as the transmitting UE 110-1, as described throughout the disclosure.

[0054] As described, Device 1000 can be configured to perform a capture and resource (re)selection procedure based on a CCA operation, including setting a selection window based on the expected CCA uptime and / or excluding RBs experiencing a consistent LBT failure as indicated by the MAC layer. In some alternative or additional perspectives, Device 1000 receives information about shared COTs from a device initiating COT sharing and performs a resource selection / re-selection procedure with a selection window limited by the remaining duration of the shared COTs. Device 1000 can then transfer the shared COT to the initiating device on SL-U after CCA of type 2A / 2B / 2C.

[0055] In some implementations, the device 1000 may include application switching logic 1002, baseband switching logic 1004, high-frequency switching logic 1006, front-end module (FEM) switching logic 1008, one or more antennas 1010, and power management switching logic (PMC) 1012, coupled together at least as shown. In some aspects, the device 1000 may include fewer elements (e.g., a RAN node may not use application switching logic 1002 and instead include a processor / controller to process IP data received from a CN, such as 5GC, or an Evolved Packet Core (EPC)). In some respects, the device can include 1000 additional elements, such as memory / storage, displays, cameras, sensors (including one or more temperature sensors, such as a single temperature sensor, a variety of temperature sensors at different locations in the device 1000, etc.).) or input / output interfaces (I / O interfaces). In other implementations, the components described below may be included in more than one device (e.g., the switching logic may be included separately in more than one device for Cloud RAN (C-RAN) implementations).

[0056] The application switching logic 1002 can include one or more application processors. For example, the application switching logic 1002 can include, but is not limited to, switching logic such as one or more single-core or multi-core processors. The processor(s) can include any combination of general-purpose and dedicated processors (e.g., graphics processors, application processors, etc.). The processors can be coupled to or include memory and can be configured to execute instructions stored in memory to allow different applications or operating systems to run on the device 1000. In some implementations, processors of the application switching logic 1002 can process IP data packets received from a CN.

[0057] The baseband switching logic 1004 can include, but is not limited to, switching logic such as one or more single-core or multi-core processors. The baseband switching logic 1004 can include one or more baseband processors or control logic to process baseband signals received by a receive signal path of the RF switching logic 1006 and to generate baseband signals for a transmit signal path of the RF switching logic 1006. The baseband switching logic 1004 can be connected to the application switching logic 1002 for generating and processing the baseband signals and for controlling the operation of the RF switching logic 1006. In some implementations, the baseband switching logic 1004 can, for example, switch to a 3G baseband processor 1004A, a 4G baseband processor 1004B, a 5G baseband processor 1004C, or other baseband processors 1004D for other existing, under development, or future generations (e.g., 2G, 6G, etc.).The baseband switching logic 1004 (e.g., one or more baseband processors 1004A-D) can handle various radio control functions that enable communication with one or more radio networks via the RF switching logic 1006. In other implementations, some or all of the functionality of the baseband processors 1004A-D can be enclosed in modules stored in memory 1004G and executed by a central processing unit (CPU) 1004E. The radio control functions can include, but are not limited to, signal modulation / demodulation, encoding / decoding, RF shifting, etc. In some implementations, the modulation / demodulation switching logic of the baseband switching logic 1004 can include a Fast Fourier Transform (FFT), precoding, or constellation assignment / unassignment functionality.In some implementations, the encoding / decoding switching logic of baseband switching logic 1004 may include convolution, tail-biting convolution, turbo, viterbi, or low-density parity check (LDPC) encoding / decoding functionality. Modulation / demodulation and encoding / decoding implementations are not limited to these examples and may include other suitable functions in other implementations.

[0058] In some implementations, the 1004 baseband switching logic may include one or more 1004F digital audio signal processors (DSPs). The 1004F audio DSPs may include compression / decompression and echo cancellation elements, and in other implementations, may include other suitable processing elements. Baseband switching logic components may be appropriately combined on a single chip or chipset, or in some implementations, they may be placed on the same printed circuit board. In some implementations, some or all of the associated components of the 1004 baseband switching logic and the 1002 application switching logic may be implemented together, as on a system-on-a-chip (SoC).

[0059] In some implementations, the 1004 baseband switching logic can provide communication compatible with one or more radio technologies. For example, in some implementations, the 1004 baseband switching logic can support communication with an NG-RAN, an developed universal terrestrial radio / access network (EUTRAN), other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), a wireless personal area network (WPAN), and so on. Implementations in which the 1004 baseband switching logic is configured to support radio communications of more than one wireless protocol can be referred to as multi-mode baseband switching logic.

[0060] The RF switching logic 1006 enables communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various implementations, the RF switching logic 1006 can include switches, filters, amplifiers, etc., to facilitate communication with the wireless network. The RF switching logic 1006 can include a receive signal path, which may contain switching logic for step-down conversion of RF signals received by the FEM switching logic 1008 and provide baseband signals to the baseband switching logic 1004. The RF switching logic 1006 can also include a transmit signal path, which may contain switching logic for step-up conversion of the baseband signals provided by the baseband switching logic 1004 and provide RF output signals to the FEM switching logic 1008 for transmission.

[0061] In some implementations, the receive signal path of the RF switching logic 1006 may include a mixer switching logic 1006A, an amplifier switching logic 1006B, and a filter switching logic 1006C. In some implementations, the transmit signal path of the RF switching logic 1006 may include a filter switching logic 1006C and a mixer switching logic 1006A. The RF switching logic 1006 may also include a synthesizer switching logic 1006D for synthesizing a frequency for use by the mixer switching logic 1006A of the receive signal path and the transmit signal path. In some implementations, the mixer switching logic 1006A of the receive signal path can be configured to down-convert the RF signals received by the FEM switching logic 1008 based on the synthesized frequency provided by the synthesizer switching logic 1006D.The amplifier switching logic 1006B can be configured to amplify the down-converted signals, and the filter switching logic 1006C can be a low-pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to produce output baseband signals. Output baseband signals can be provided to the baseband switching logic 1004 for further processing. In some implementations, the output baseband signals may be zero-frequency baseband signals, although this is not a requirement. In some implementations, the mixer switching logic 1006A of the receive signal path may include passive mixers, although the scope of implementations is not limited in this respect.

[0062] FEM switching logic 1008 can include a receive signal path, which may include switching logic configured to operate on RF signals received by one or more antennas 1010, amplify the received signals, and provide amplified versions of the received signals to the RF switching logic 1006 for further processing. FEM switching logic 1008 can also include a transmit signal path, which may include switching logic configured to amplify signals for transmission provided by the RF switching logic 1006 for transmission through one or more of the antennas 1010. In various implementations, the amplification through the transmission or the receive signal path can take place exclusively in the RF switching logic 1006, exclusively in the FEM switching logic 1008, or in both the RF switching logic 1006 and the FEM switching logic 1008.

[0063] In some implementations, the PMC 1012 can manage the power supplied to the baseband switching logic 1004. Specifically, the PMC 1012 can control the power source selection, voltage scaling, battery charging, or DC-DC conversion. The PMC 1012 can often be included when the device 1000 can be powered by a battery, for example, when the device is enclosed in a UE (Universal Assembly). The PMC 1012 can increase power conversion efficiency while providing the desired implementation size and heat dissipation characteristics. Fig. Figure 10 shows the PMC 1012, which is only coupled to the baseband switching logic 1004. In other implementations, however, the PMC 1012 can be additionally or alternatively coupled to other components, such as, but not limited to, the application switching logic 1002, the RF switching logic 1006, or the FEM switching logic 1008, and perform similar power management operations for them.

[0064] Application Switching Logic 1002 processors and Baseband Switching Logic 1004 processors can be used to execute elements of one or more instances of a protocol stack. For example, Baseband Switching Logic 1004 processors can be used alone or in combination to perform Layer 3, Layer 2, or Layer 1 functionality, while Baseband Switching Logic 1004 processors can utilize data received from these layers (e.g., packet data) and also perform Layer 4 functionality (e.g., Transmission Communication Protocol (TCP) layers and User Data Packet Protocol (UDP) layers). As mentioned herein, Layer 3 can include an RRC layer, Layer 2 can include a Medium Access Control (MAC) layer, a Radio Link Control (RLC) layer, and a Packet Data Convergence Protocol (PDCP) layer, and Layer 1 can include a physical layer (PHY) of a UE / RAN node.

[0065] Fig. Figure 11 is a diagram of examples of communication models according to one or more of the implementations described herein. As explained above, the baseband switching logic 1004 of Fig. The system comprises 10 processors 1004A to 1004E and a memory 1004G used by these processors. The processors 1004A to 1004E can be collectively referred to as the baseband processor. Each of the processors 1004A to 1004E can include a memory interface 1104A to 1104E for sending / receiving data to / from the memory 1004G. In some respects, the baseband switching logic 1004 or its components, such as the baseband processor, can also be or be included as a UE such as the sending UE 110-1 or the receiving UE 110-2, as described in this disclosure.

[0066] The baseband switching logic 1004 can further include one or more interfaces for communicative coupling with other switching logics / devices, such as a memory interface 1112 (e.g., an interface for sending / receiving data to / from a memory outside the baseband switching logic 1004), an application switching logic interface 1114 (e.g., an interface for sending / receiving data to / from the application switching logic 1002). Fig. 10), an RF switching logic interface 1116 (e.g. an interface for sending / receiving data to / from the RF switching logic 1006) Fig.10), a wireless hardware connectivity interface 1118 (e.g., an interface for sending / receiving data to / from Near Field Communication (NFC) components, Bluetooth components, Wi-Fi components, and other communication components) and a power management interface 1120 (e.g., an interface for sending / receiving power or control signals to / from the PMC 1012).

[0067] Examples herein may include items such as a method, means of performing operations or blocks of the method, at least one machine-readable medium containing executable instructions which, when executed by a machine (e.g., a processor (e.g., processor, etc.) with memory, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or the like), cause the machine to perform operations of the method or of a device or system for simultaneous communication using multiple communication technologies according to the implementations and examples described.

[0068] Example 1 is a setup for a UE that includes a memory and a memory-coupled processor and is configured, when executing instructions stored in memory, to cause the UE to detect and select resources for sidelink communication in the unlicensed band (SL-U) based on a Clear Channel Assessment (CCA) operation to be performed, to perform the CCA operation for SL-U, and to transfer data to another UE using the selected resources for SL-U.

[0069] Example 2 is a facility that includes the subject of Example 1, where the selection of resources involves determining a resource selection window based on an expected CCA time of the CCA operation.

[0070] Example 3 is a setup that includes the subject of Example 2, where the expected CCA time of the CCA operation is calculated based on a value of the Channel Access Priority Class (CAPC) of the data to be transferred and a current conflict window size (“CW_p”) of the CCA operation.

[0071] Example 4 is a setup that includes the subject of any of Examples 2 to 3, wherein the resource selection window has a lower bound between the expected CCA time and a sum of the expected CCA time and a processing time Tproc,1 required for resource selection for SL-U.

[0072] Example 5 is a setup that includes the subject of Example 3, where the expected CCA time of the CCA operation is the sum of a delay duration of the CCA operation based on the CAPC value and an estimated backoff period of the CCA operation with respect to the current conflict window size (“CW_p”).

[0073] Example 6 is a setup that includes the subject of Example 5, wherein the estimated backoff period of the CCA operation is N*capture slot periods, where N is a backoff counter randomly selected by the CCA operation between 0 and the current conflict window size ("CW_p").

[0074] Example 7 is a facility that includes the subject of one of Examples 3 or 5, where the expected CCA time of the CCA operation is calculated based on a channel occupancy rate (Roc).

[0075] Example 8 is a device that includes the subject of Example 7, wherein the channel occupancy rate (Roc) is defined as a percentage of samples with a measurement of the received signal strength (RSSI) taken in a measurement window and reaching a channel occupancy threshold.

[0076] Example 9 is a setup that includes the subject of Example 7, wherein the channel occupancy rate (Roc) is defined as the percentage of capture slots identified as occupied by the CCA process, out of a total number of capture slots within a predefined time window.

[0077] Example 10 is a setup that includes the subject of Example 7, where the expected CCA time of the CCA operation is calculated as 16 µs + m*9 µs + N*9 µs / (1-Roc), where m is an integer relating to the CAPC value, and N is another integer randomly selected by the CCA operation between 0 and the current conflict window size ("CW_p").

[0078] Example 11 is a setup that includes the subject of Example 2, wherein the resource selection window has an upper limit that is greater than the sum of a minimum selection period and the expected CCA time, but not greater than a remaining packet delay budget (PDB).

[0079] Example 12 is a setup that includes the subject of Example 11, where the expected CCA time is specified as Td + CW_p, where Td is a delay period of the CCA operation and CW_p is an actual conflict window size of the CCA operation.

[0080] Example 13 is a setup that includes the subject of Example 11, where the expected CCA time is specified as Td + CW_p / (1-Roc), where Td is a delay period of the CCA operation, CW_p is a current conflict window size of the CCA operation, and Roc is a channel occupancy rate.

[0081] Example 14 is a setup that includes the subject of Example 1, wherein the selection of resources involves determining a resource selection window and obtaining an initial set of candidate resources and eliminating candidates to form a set of fitted candidate resources based on a specification of a consistent List-Before-Talk (LBT) error.

[0082] Example 15 is a setup that includes the subject of Example 14, where the indication of a consistent LBT error is provided from a MAC layer to a physical layer per RB set.

[0083] Example 16 is a setup that includes the subject of Example 15, wherein the processor is further configured to cause the UE to determine a number of remaining candidate resources from the set of matched candidate resources that is less than a predefined threshold, to inform the MAC layer of the candidate inadequacy, and to perform a re-selection of the resource pool by the MAC layer.

[0084] Example 17 is a setup that includes the subject of Example 1, wherein the processor is configured to cause the UE to receive sidelink control information (SCI) from an initializing UE, including shared channel occupancy time (COT) information, where the shared COT information includes information about a shared COT initiated by the initializing UE. Resource selection involves determining a resource selection window with a start time and an end time, where the end time is no later than the remaining COT duration and the remaining packet delay budget (PDB).

[0085] Example 18 is a procedure for operating a UE, and the procedure comprises determining a resource selection window for sidelink communication in the unlicensed band (SL-U), obtaining an initial set of candidate resources within the resource selection window, excluding one or more resource blocks from the initial set of candidate resources based on a specification of a consistent Listen-Before-Talk (LBT) error from a MAC layer to form a set of adapted candidate resources, selecting resources from the set of adapted candidate resources, and transferring data to another UE using the selected resources.

[0086] Example 19 is a procedure that includes the subject matter of Example 18 and further comprises determining a number of remaining candidate resources from the set of matched candidate resources that is less than a predefined threshold, notifying the MAC layer of the candidate inadequacy, and performing a reselection of the resource pool by the MAC layer.

[0087] Example 20 is a baseband process for a UE and comprises a memory and a memory-coupled processor, and, when executing instructions stored in memory, is configured to cause the UE to receive sidelink control information (SCI) from an initializing UE, which injects shared channel occupancy time (COT) information, where the shared COT information includes information about a shared COT initiated by the initializing UE, to determine a resource selection window for sidelink communication in an unlicensed spectrum (SL-U) with an end time that is not later than a remaining COT duration or a remaining packet delay budget (PDB), to select resources for SL-U during the resource selection window, and to transmit data to the initializing UE using the selected resources for SL-U.

[0088] Example 21 is a procedure that includes any action or combination of actions as substantially described in detail herein.

[0089] Example 22 is a method as substantially described herein with reference to each figure or combination of figures included herein, or with reference to each paragraph or combination of paragraphs in the detailed description.

[0090] Example 23 is a user setup configured to perform any action or combination of actions as described herein in the detailed description, essentially as included in the user setup.

[0091] Example 24 is a network node configured to perform any action or combination of actions as described herein in detail, essentially as enclosed in the network node.

[0092] Example 25 is a non-volatile, computer-readable medium that stores instructions which, when executed, cause the performance of any action or combination of actions as substantially described in detail herein.

[0093] Example 26 is a user facility baseband processor configured to perform any action or combination of actions as described herein in detail, substantially as included in the user facility.

[0094] Example 27 is a network node baseband processor configured to perform any action or combination of actions as described herein in the detailed description, essentially as included in the user setup.

[0095] The foregoing description of illustrated examples, implementations, aspects, etc., of the present disclosure, including what is described in the summary, does not claim to be exhaustive or to limit the disclosed aspects to the exact disclosed forms. Although specific examples, implementations, aspects, etc., are described herein for illustrative purposes, various modifications are possible, which are considered within the scope of protection of such examples, implementations, aspects, etc., as the person skilled in the art in the relevant field can recognize.

[0096] In this respect, although the disclosed subject matter has been described in connection with various examples, implementations, and viewpoints, etc., and related figures where applicable, it is understood that other similar viewpoints may be used, or modifications and additions may be made to the disclosed subject matter to perform the same, similar, alternative, or substitute functions of the subject matter without departing from it. Therefore, the disclosed subject matter should not be limited to a single example, implementation, or viewpoint described herein, but rather should be interpreted broadly and comprehensively in accordance with the claims set forth below.

[0097] Particularly with regard to the various functions performed by the components or structures (assemblies, devices, circuits, systems, etc.) described above, the terms used to describe these components, unless otherwise specified, shall correspond to any component or structure that performs the stated function of the described component (that is, for example, functionally equivalent), even if it is not structurally equivalent to the disclosed structure that performs the function in the exemplary implementations illustrated herein. Furthermore, although a particular feature may have been disclosed with respect to only one of several implementations, such a feature may be combined with one or more other features of the other implementations, as may be desired and advantageous for any given application.

[0098] As used herein, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or”. That is to say, unless otherwise specified or evident from the context, “X uses A or B” is to mean any of the natural inclusive permutations. That is to say, if X uses A; X uses B; or X uses both A and B, then “X uses A or B” is satisfied in each of the preceding cases. Furthermore, the articles “a” and “an”, as used in this application and the attached claims, should generally be interpreted as meaning “one or more”, unless otherwise specified or evident from the context that they are directed towards a singular form.Furthermore, the terms “including”, “encompassing”, “having”, “exhibiting”, “with”, or variations thereof, as used in the detailed description or claims, are to be understood as inclusive terms in a similar way to the term “comprehensive”. Additionally, in situations where one or more numbered elements are discussed (e.g., a “first X”, a “second X”, etc.), the one or more numbered elements may generally be different or they may be the same, although in some situations the context may indicate that they are different or that they are the same.

[0099] It is understood that the use of personally identifiable information should follow data protection regulations and practices that are generally recognized as meeting or exceeding industry or regulatory requirements for protecting user privacy. In particular, personally identifiable information should be managed and handled in a manner that minimizes the risks of accidental or unauthorized access or use, and the nature of any authorized use should be clearly communicated to users.

Claims

[1] Setup for a user facility (UE), comprising: a storage facility; and a baseband processor coupled to the memory and configured, when executing instructions stored in memory, to cause the UE to: Identifying and selecting resources, based on a Clear Channel Assessment (CCA) process to be performed, for sidelink communication in the unlicensed band (SL-U); Performing the CCA process for SL-U; and Transferring data to another UE using the selected resources for the SL-U. [2] Device according to claim 1, wherein the selection of resources comprises determining a resource selection window based on an expected CCA time of the CCA process. [3] Device according to claim 2, wherein the expected CCA time of the CCA operation is calculated based on a Channel Access Priority Class (CAPC) value of the data to be transferred and a current conflict window size (“CW_p”) of the CCA operation. [4] Device according to one of claims 2 to 3, wherein the resource selection window has a lower bound between the expected CCA time and a sum of the expected CCA time and a processing time Tproc,1 required for resource selection for SL-U. [5] Device according to claim 3, wherein the expected CCA time of the CCA operation is the sum of a delay duration of the CCA operation based on the CAPC value and an estimated backoff period of the CCA operation with respect to the current conflict window size (“CW_p”). [6] Device according to claim 5, wherein the estimated backoff period of the CCA operation is N* acquisition slot periods, where N is a backoff counter that is randomly selected by the CCA operation between 0 and the current conflict window size (“CW_p”). [7] Device according to one of claims 3 or 5, wherein the expected CCA time of the CCA process is calculated based on a channel occupancy rate (Roc). [8] Device according to claim 7, wherein the channel occupancy rate (Roc) is defined as the percentage of samples with a measurement of the received signal strength indicator (RSSI) measured in a measurement window that meets a channel occupancy threshold. [9] Device according to claim 7, wherein the channel occupancy rate (Roc) is defined as the percentage of the capture slots that are identified as occupied slots by the CCA process out of a total number of capture slots within a predefined time window. [10] Device according to claim 7, wherein the expected CCA time of the CCA operation is calculated as 16 µs + m * 9 µs + N * 9 µs / (1-Roc), where m is an integer relating to the CAPC value and N is another integer randomly selected by the CCA operation between 0 and the current conflict window size (“CW_p”). [11] Device according to claim 2, wherein the resource selection window has an upper limit which is greater than the sum of a minimum selection period and the expected CCA time, but does not exceed a remaining packet delay budget (PDB). [12] Device according to claim 11, wherein the expected CCA time is defined as Td + CW_p, where Td is a delay period of the CCA operation and CW_p is a current conflict window size of the CCA operation. [13] Device according to claim 11, wherein the expected CCA time is defined as Td + Cw_p / (1-Roc), where Td is a delay period of the CCA operation, CW_p is a current conflict window size of the CCA operation, and Roc is a channel occupancy rate. [14] Equipment according to claim 1, wherein the selection of resources comprises: Identifying a resource selection window; and Obtaining an initial set of candidate resources and eliminating candidates to form a set of tailored candidate resources, based on a report of a consistent Listen-Before-Talk (LBT) error. [15] Device according to claim 14, wherein the indication of a consistent LBT error is provided from a MAC layer to a physical layer per RB set. [16] Device according to claim 15, wherein the processor is further configured to cause the UE to: Determining a number of remaining candidate resources from the set of matched candidate resources that is less than a predefined threshold; Notify the MAC layer of the candidate inadequacy; and Performing a re-selection of the resource pool by the MAC layer. [17] Device according to claim 1, wherein the processor is further configured to cause the UE to: Receiving, from an initiating UE, sidelink control information (SCI), including shared channel occupancy time (COT) information, wherein the shared COT information includes information about a shared COT initiated by the initiating UE; and where the selection of resources includes defining a resource selection window with a start time and an end time, where the end time is no later than a remaining COT duration and a remaining packet delay budget (PDB). [18] Methods for operating a user establishment (UE), comprising: Determining a resource selection window for sidelink communication in the unlicensed band (SL-U); Obtaining an initial set of candidate resources within the resource selection window; Excluding one or more resource blocks, based on a consistent Listen-Before-Talk (LBT) error indication from a MAC layer, from the initial set of candidate resources to form a set of matched candidate resources; Selecting resources from the set of matched candidate resources; and Transferring data to another UE using the selected resources. [19] The method of claim 18, further comprising: Determining a number of remaining candidate resources from the set of matched candidate resources that is less than a predefined threshold; Notify the MAC layer of the candidate's inadequacy; and Performing a re-selection of the resource pool by the MAC layer. [20] Baseband processor for a user facility (UE), comprising: a storage facility; and a baseband processor coupled to the memory and configured, when executing instructions stored in memory, to cause the UE to: Receiving, from an initiating UE, sidelink control information (SCI), including shared channel occupancy time (COT) information, wherein the shared COT information includes information about a shared COT initiated by the initiating UE; Determining a resource selection window for sidelink communication in an unlicensed spectrum (SL-U) with an end time that is no later than a remaining COT duration or a remaining packet delay budget (PDB). Selecting resources for Sl-U in the resource selection window; and Transfer data to the initializing UE using the selected resources for SL-U.

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