Method and apparatus for sharing channel occupancy time on unlicensed spectrum

Abstract

The present application relates to a method and apparatus for sharing channel occupancy time. One embodiment of the present application provides a method performed by a user equipment (UE) for wireless communication, the method comprising: receiving a first indicator from a base station (BS), the first indicator requesting the UE to share a channel occupancy time (COT) for downlink transmission within the COT, wherein the COT is initiated by the UE to transmit uplink data; determining a first channel access priority level (CAPC) value; initiating the COT by performing a channel access procedure using the first CAPC value; and transmitting at least a portion of the uplink data to the BS in the COT.

Description

Technical Field

[0001] The present application relates to a method and apparatus for a 3rd Generation Partnership Project (3GPP) network, and more particularly to a method and apparatus for sharing channel occupation time (COT) in a NR network. Background Art

[0002] Base stations (BS) and user equipment (UE) can operate in both licensed and unlicensed spectrum. In the licensed assisted access (FeLAA) further enhanced by Long Term Evolution (LTE) Rel-15, autonomous uplink (AUL) transmission for unlicensed spectrum is supported. In this way, the UE can perform physical uplink shared channel (PUSCH) transmission on the configured time-frequency resources without waiting for the uplink (UL) grant from the BS. Moreover, the BS can avoid transmitting the UL grant and performing the channel access procedure for transmitting the UL grant.

[0003] To improve the utilization of radio resources, the COT initiated by the UE for AUL transmission can be shared with the base station for downlink (DL) transmission. Summary of the invention

[0004] It may be desirable to provide a solution for sharing COT in NR networks.

[0005] One embodiment of the present application provides a method performed by a user equipment (UE) for wireless communication. The method includes: receiving a first indicator from a base station (BS), the first indicator requesting the UE to share a channel occupation time (COT) for downlink transmission within the COT, wherein the COT is initiated by the UE to transmit uplink data; determining a first channel access priority level (CAPC) value; initiating the COT by performing a channel access procedure using the first CAPC value; and transmitting at least a portion of the uplink data to the BS in the COT.

[0006] Another embodiment of the present application provides an apparatus comprising: a non-transitory computer-readable medium having computer-executable instructions stored thereon; a receiving circuit system; a transmitting circuit system; and a processor coupled to the non-transitory computer-readable medium, the receiving circuit system, and the transmitting circuit system, wherein the computer-executable instructions cause the processor, the receiving circuit system, and the transmitting circuit system to implement the above-mentioned method.

[0007] Another embodiment of the present application provides a method performed by a base station (BS) for wireless communication. The method includes: transmitting a first indicator to a user equipment (UE), the first indicator requesting the UE to share a channel occupation time (COT) for downlink transmission within the COT, wherein the COT is initiated by the UE to transmit uplink data; and receiving the uplink data from the UE within the COT.

[0008] Yet another embodiment of the present application provides an apparatus comprising: a non-transitory computer-readable medium having computer-executable instructions stored thereon; a receiving circuit system; a transmitting circuit system; and a processor coupled to the non-transitory computer-readable medium, the receiving circuit system, and the transmitting circuit system, wherein the computer-executable instructions cause the processor, the receiving circuit system, and the transmitting circuit system to implement the above-mentioned method. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 A schematic diagram illustrating a wireless communication system according to some embodiments of the present application is illustrated.

[0010] Figure 2 Illustrating COT initiated for a UE scheduled for PUSCH according to some embodiments of the present application.

[0011] Figure 3 The diagram illustrates a COT initiated for a UE configured with a granted PUSCH according to some embodiments of the present application.

[0012] Figure 4 A flow chart illustrating an exemplary procedure for sharing a UE-initiated COT for a scheduled PUSCH with a base station according to some embodiments of the present application.

[0013] Figure 5 A flow chart illustrating another exemplary procedure for sharing a UE-initiated COT for a scheduled PUSCH with a base station in accordance with some embodiments of the present application.

[0014] Figure 6 A flow chart illustrating an exemplary procedure for sharing a COT initiated by a UE for which a granted PUSCH is configured with a base station according to some embodiments of the present application.

[0015] Figure 7 A flow chart illustrating another exemplary procedure for sharing a UE-initiated COT for a configured granted PUSCH with a base station according to some embodiments of the present application.

[0016] Figure 8Illustrated is a UE initiated COT with both UL to DL switching point and DL to UL switching point according to some embodiments of the present application.

[0017] Fig. 9 A block diagram of a UE is illustrated according to some embodiments of the present disclosure.

[0018] Fig.10 A block diagram of a BS is depicted in accordance with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0019] The detailed description of the accompanying drawings is intended as a description of the currently preferred embodiments of the present invention, and is not intended to represent the only form in which the present invention can be practiced. It should be understood that the same or equivalent functions can be achieved by different embodiments that are also intended to be included in the spirit and scope of the present invention.

[0020] The embodiments provide a method and apparatus for transmitting downlink (DL) or uplink (UL) data on an unlicensed spectrum. For ease of understanding, the embodiments are provided under specific network architectures and new service scenarios such as 3GPP 5G, 3GPP LTE version 8, etc. It is clear to those skilled in the art that, with the development of network architectures and new service scenarios, the embodiments of the present disclosure are also applicable to similar technical problems.

[0021] Figure 1 A wireless communication system 100 is depicted in accordance with an embodiment of the present disclosure.

[0022] like Figure 1 , the wireless communication system 100 includes a UE 101 and a BS 102. Specifically, for illustrative purposes only, the wireless communication system 100 includes three UEs 101 and three BSs 102. Figure 1 A specific number of UEs 101 and BSs 102 are depicted in FIG. 1 , but those skilled in the art will recognize that any number of UEs 101 and BSs 102 may be included in the wireless communication system 100 .

[0023] UE 101 may include a computing device, such as a desktop computer, a laptop computer, a personal digital assistant (PDA), a tablet computer, a smart TV (e.g., a TV connected to the Internet), a set-top box, a game console, a security system (including a security camera), a car computer, a network device (e.g., a router, a switch, and a modem), etc. According to an embodiment of the present disclosure, UE 101 may include a portable wireless communication device, a smart phone, a cellular phone, a flip phone, a device with a subscriber identity module, a personal computer, a selective call receiver, or any other device capable of sending and receiving communication signals on a wireless network. In some embodiments, UE 101 includes a wearable device, such as a smart watch, a fitness band, an optical head-mounted display, etc. In addition, UE 101 may be referred to as a subscriber unit, a mobile phone, a mobile station, a user, a terminal, a mobile terminal, a wireless terminal, a fixed terminal, a subscriber station, a user terminal or a device, or described using other terms used in the art. UE 101 may communicate directly with BS 102 via an uplink (UL) communication signal.

[0024] BSs 102 may be distributed over a geographic area. In some embodiments, each of BSs 102 may also be referred to as an access point, an access terminal, a base station, a macro cell, a Node B, an enhanced Node B (eNB), a gNB, a Home Node B, a relay node or a device, or described using other terms used in the art. BSs 102 are typically part of a radio access network, which may include one or more controllers communicatively coupled to one or more corresponding BSs 102.

[0025] The wireless communication system 100 is compatible with any type of network capable of sending and receiving wireless communication signals. For example, the wireless communication system 100 is compatible with a wireless communication network, a cellular telephone network, a network based on time division multiple access (TDMA), a network based on code division multiple access (CDMA), a network based on orthogonal frequency division multiple access (OFDMA), an LTE network, a network based on the third generation partnership project (3GPP), a 3GPP 5G network, a satellite communication network, a high altitude platform network, and / or other communication networks.

[0026] In one embodiment, the wireless communication system 100 is compatible with the 5G New Radio (NR) of the 3GPP protocol, wherein the BS 102 transmits data using an Orthogonal Frequency Division Multiplexing (OFDM) modulation scheme on the downlink, and the UE 101 transmits data using a Discrete Fourier Transform-Diffusion-Orthogonal Frequency Division Multiplexing (DFT-S-OFDM) or Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) scheme on the uplink. However, more generally, the wireless communication system 100 may implement some other open or proprietary communication protocols (for example, WiMAX) as well as other protocols.

[0027] In other embodiments, BS 102 may communicate using other communication protocols (e.g., IEEE 802.11 wireless communication protocol family). In addition, in some embodiments, BS 102 may communicate via licensed spectrum, while in other embodiments, BS 102 may communicate via unlicensed spectrum. The present disclosure is not intended to be limited to implementations of any particular wireless communication system architecture or protocol. In another embodiment, BS 102 may communicate with UE 101 using 3GPP 5G protocols.

[0028] In LTE Rel-15 FeLAA, autonomous uplink (AUL) transmission is supported on the unlicensed spectrum, so that not only can the UE transmit PUSCH on the configured time-frequency resources without waiting for UL authorization, but the eNB can skip the listen-before-talk (LBT) procedure and the procedure of transmitting UL authorization. Like semi-persistent scheduling (SPS) transmission, the activation and deactivation of AUL transmission requires downlink control information (DCI), and the cyclic redundancy check (CRC) of DCI is scrambled with a specific radio network temporary identity (RNTI) AUL C-RNTI. For AUL transmission, the UE transmits AUL-UCI on the associated AUL PUSCH. AUL-UCI includes 4-bit HARQ process ID, 1 or 2-bit NDI (1 bit for TM1, 2 bits for TM2), 2-bit RV, 16-bit UE-ID, 1-bit PUSCH start point (indicating symbol 0 or 1), 1-bit PUSCH end point (indicating symbol 12 or 13), 1-bit COT sharing, and 16-bit CRC.

[0029] In LTE Rel-15 FeLAA, for AUL transmissions, the UE transmits the AUL PUSCH using a Type 1 channel access procedure (also known as LBTCat.4), and determines the channel access priority (CAPC) value from Table 4.2.1-1 in TS37.213 (reproduced below) based on the UL traffic data. This mechanism is completely under network control because the network maps logical channels to channel access priority values. In addition, if the AUL PUSCH falls within the eNB initiated COT, whether the AUL PUSCH is allowed to be transmitted within the eNB initiated COT depends on a one-bit COT sharing indicator in the common physical data control channel (PDCCH) with a CRC scrambled by the CC-RNTI.

[0030]

[0031]

[0032] Table 4.2.1-1: Channel access priority for UL

[0033] If the one-bit COT sharing indicator is set to true, the UE may perform AUL transmissions corresponding to any priority level of UL traffic data using channel access type 2. If the one-bit COT sharing indicator is set to false, the UE shall not transmit AUL transmissions in a COT initiated by the eNB.

[0034] Similarly, the COT initiated by the UE performing LBT Cat.4 AUL transmission can also be shared with the eNB for DL ​​transmission. Such permission to perform DL transmission within the UE initiated COT is indicated to the eNB by a one-bit COT sharing indicator in the AUL-UCI. If the one-bit COT sharing indicator is set to true, it implies that the UE intends to share its COT with the eNB for DL ​​transmission. If the one-bit COT sharing indicator is set to false, it implies that the UE does not intend to share its COT with the eNB.

[0035] For NR-based access to unlicensed spectrum (NR-U), the UE-initiated COT for configured authorized UL transmissions can be shared with the gNB for DL ​​transmissions. In general, there are two mechanisms for the UE and gNB to share the COT with each other, namely, the gNB-initiated COT for scheduled PUSCH transmissions and AUL PUSCH transmissions will be shared with the UE, and the UE-initiated COT for AULPUSCH transmissions can be shared with the gNB for PDCCH transmissions.

[0036] However, for the UE-initiated COT sharing mechanism, it is purely up to the UE to decide whether to share its COT with the gNB for DL ​​transmissions, and if UL to DL sharing is allowed, then which slots / symbols to share with the gNB. Obviously, in this procedure, the network cannot control this sharing. That is, when the gNB has more urgent DL traffic data, or the gNB needs to transmit periodic DL signals such as synchronization signal (SS) / physical broadcast channel (PBCH), group common PDCCH (GC-PDCCH), PDSCH carrying system information block 1 (SIB1), Msg.2 / 4, then the gNB has to wait for AUL transmission and perform LBT Cat.4 after completing the AUL transmission. This UE-initiated COT sharing mechanism can lead to system performance degradation. In order to achieve more efficient spectrum usage, from the system perspective, the gNB needs to have influence on this UL to DL sharing and request the UE to share the UE-initiated COT for DL ​​transmissions whenever the gNB needs to transmit more urgent DL traffic data.

[0037] One object of the present disclosure is to address several issues to facilitate a BS controlled UL to DL sharing mechanism.

[0038] First, a mechanism is provided for the BS to request the UE to share the UE-initiated COT for scheduled PUSCH transmission, so that the BS can transmit DL transmission in the COT based on its own decision. Figure 2 The diagram illustrates a COT initiated for a UE scheduled for PUSCH according to some embodiments of the present application. Figure 2 As depicted in FIG, COT is initiated by the UE through a LBTC Cat.4 procedure performed in time frame 202. After transmitting the PUSCH scheduled by DCI 210 in time frame 204, time frame 208 is shared with the BS to transmit DL transmissions. The gap 206 between time frame 204 and time frame 208 is used for the BS to perform the LBT Cat.2 procedure. That is, several symbols of the scheduled PUSCH scheduled to be transmitted in gap 206 are blanked.

[0039] Secondly, the present disclosure also provides a mechanism for the BS to request the UE to share the COT initiated by the UE to perform the configured authorized PUSCH transmission. Figure 3 The diagram illustrates the COT initiated for a UE configured with a PUSCH grant according to some embodiments of the present application. Figure 3, COT is initiated by the UE through the LBT Cat.4 procedure performed in time frame 302. After transmitting the configured granted PUSCH in time frame 304, time frame 308 is shared with the BS to transmit DL transmission. The gap 306 between time frame 304 and time frame 308 is used for the BS to perform the LBT Cat.2 procedure. That is, several symbols of the configured granted PUSCH scheduled to be transmitted in gap 306 are blanked.

[0040] Figure 4 A flowchart illustrating an exemplary procedure for sharing a UE-initiated COT with a base station for scheduled PUSCH according to some embodiments of the present application. In operation 402, the BS may transmit a COT sharing requested indicator to the UE in order to request the UE to share the UE-initiated COT with the BS for downlink transmission. In a preferred embodiment, the COT sharing requested indicator is a one-bit indicator included in a field of a DCI (e.g., an UL grant). It can be envisioned that the DCI is used to schedule one or more PUSCHs in order to transmit uplink data in the UE-initiated COT. Therefore, the BS may dynamically request the UE to share the UE-initiated COT for downlink transmission. In addition, the UL grant may include a COT sharing indicator indicating that the BS-initiated COT is shared with the UE for PUSCH transmission.

[0041] In operation 404, the BS may transmit another indicator to the UE, the other indicator indicating the duration requested for the downlink transmission. In a preferred embodiment, such an indicator may also be included in a field of the DCI. The requested duration may be indicated as a number of time slots or a number of symbols or a combination of a number of time slots and a number of symbols. In another embodiment, the duration requested for the downlink transmission may be configured by RRC signaling. For example, the requested duration may be determined from a candidate group consisting of, for example, 2 symbols, 3 symbols, 4 symbols, 8 symbols, and 12 symbols; 1 time slot, 2 time slots, 4 time slots, 6 time slots, and 8 time slots; and so on.

[0042] In some embodiments, operation 404 may be omitted. For example, the duration of the downlink transmission may be preconfigured or fixed in the specification, and thus an indicator of the requested DL duration need not be transmitted to the UE.

[0043] In operation 406, upon receiving the COT sharing requested indicator, the UE may select a CAPC value from a set of predefined CAPC values, such as the CAPC values ​​defined in Table 4.2.1-1 in TS37.213 mentioned above. In a preferred embodiment, the UE may select a CAPC value based on the sum of the duration required to transmit uplink data and the duration requested for downlink transmission. The UE may first select the shortest MCOT that can accommodate both UL transmission and DL transmission from a set of predefined CAPC values, and then further determine the CAPC value based on Table 4.2.1-1 and the selected COT.

[0044] For example, if the duration required to transmit uplink data is 2ms and the duration requested for downlink transmission is 1ms, the COT initiated by the UE should have at least 3ms in order to accommodate both the duration of UL transmission and the duration of DL transmission. As shown in Table 4.2.1-1, a CAPC value of "1" corresponds to a maximum COT (MCOT) of 2ms; a CAPC value of "2" corresponds to a MCOT of 4ms; a CAPC value of "3" corresponds to a MCOT of 6ms or 10ms; and a CAPC value of "4" also corresponds to a MCOT of 6ms or 10ms. Therefore, the UE will select a CAPC value of "2" to perform the LBT Cat.4 procedure, for example, selecting a MCOT of 4ms, in order to ensure that the initiated COT can accommodate both the duration of UL transmission and the duration of DL transmission.

[0045] In another embodiment, the UE selects a CAPC value from a set of predefined CAPC values ​​based on the uplink data. It is contemplated that the CAPC value may be selected based on the quality of service (QoS) requirements of the uplink data, i.e., the lowest channel access priority level (i.e., the highest CAPC value) of the logical channel with data available for transmission. Since the requested duration of the DL transmission does not affect the determination of the CAPC value, it may not be necessary to inform the UE of the requested duration of the DL transmission. Therefore, in some embodiments, operation 404 may be omitted.

[0046] In operation 410, the UE determines whether the MCOT of the selected CAPC value is sufficient to accommodate both the duration of the UL transmission and the duration of the DL transmission. If the COT is determined based on both the duration of the UL transmission and the duration of the DL transmission, the operation of 410 may be omitted. If the COT is determined based on the UL transmission, operation 410 is preferred.

[0047] In operation 410, if the UE receives an indicator indicating that the requested duration of the DL transmission or the duration of the DL transmission is preconfigured or fixed, then in operation 410, the UE may determine whether the MCOT of the selected CAPC value is sufficient to accommodate both the duration of the UL transmission and the duration of the DL transmission. Several options for determining how the COT is distributed are provided in the present disclosure.

[0048] The first option is to prioritize uplink data. The UE transmits all scheduled PUSCHs first, and then shares the remaining COT with the BS, even if the duration of the remaining COT is shorter than the requested duration of the DL transmission.

[0049] The second option is that the BS decides which one of the uplink data and downlink transmission is prioritized. The BS can use RRC signaling to notify the UE of its decision. Therefore, if the duration of the COT is not long enough and the uplink data is prioritized, all uplink data is transmitted in the COT and the remaining COT is shared with the BS; and if the duration of the COT is not long enough and the downlink transmission is prioritized, the UE determines the duration of the uplink transmission by excluding the requested duration of the DL transmission from the determined ULMCOT. In this case, only a part of the uplink data is transmitted in the COT. In some embodiments, both the first option and the second option are applied. If there is a conflict between the two options, the BS can indicate which option is selected. In this article, the downlink transmission may include downlink data transmission, downlink control (e.g., group common PDCCH, periodic PDCCH, downlink feedback indication or other UE-specific DCI for UL configured authorization transmission, such as DL authorization or UL authorization), SS / PBCH block, SIB on PDSCH, periodic CSI-RS, etc.

[0050] Then, in operation 412, the UE performs LBT Cat.4 procedure using the selected CAPC value to initiate COT to transmit the scheduled PUSCH. Thereafter, in operation 414, the UE transmits PUSCH in the COT. The remaining COT may be shared with the BS for DL ​​transmission.

[0051] In operation 414, the UE may transmit information other than uplink data to the BS. For example, the UE may transmit a selected CAPC value (hereinafter referred to as "UL CAPC value") to the BS. The UL CAPC value may be carried as uplink control information (UCI) on a scheduled PUSCH, such as the first or last scheduled PUSCH, each scheduled PUSCH, or an associated PUCCH.

[0052] A one-bit indicator may also be included in the UCI. The one-bit indicator is a COT sharing indicator indicating whether the UE agrees to share the COT. In another embodiment, the one-bit indicator included in the UCI may indicate whether the requested downlink duration can be accommodated in the COT. In yet another embodiment, the one-bit indicator included in the UCI may indicate whether the UL to DL sharing is successful, because in some cases the UE cannot follow the BS's request for COT sharing. In some embodiments, one or more of the above indicators and the UL CAPC value are separately indicated in the UCI. In other embodiments, one or more of the above indicators are jointly encoded using the UL CAPC value.

[0053] If the UL CAPC value is determined by using Table 4.2.1-1, there are four candidate CAPC values. Therefore, at least two bits are required to indicate one of the four candidate CAPC values. In one embodiment, the two bits are attached on the scheduled PUSCH by puncturing certain resource elements (REs) immediately following the first DMRS for the PUSCH. In another embodiment, the two bits are multiplexed with the uplink shared channel (UL-SCH) on the PUSCH, for example, the modulated symbols of the two bits are pre-pended at the beginning of the modulated symbols of the UL-SCH, or the two bits are included in the MAC header or a new MAC CE. In yet another embodiment, the two bits are carried in the PUCCH associated with the scheduled PUSCH. In this embodiment, PUCCH format 0 or 1 can be used to transmit the two bits.

[0054] In operation 416, after receiving the PUSCH transmission, the BS determines whether downlink data can be transmitted in the UE-initiated COT. The BS may determine whether to share the UE-initiated COT with the BS based on the value of the COT sharing indicator included in the UCI. In some other embodiments, the BS may determine whether to transmit downlink data in the UE-initiated COT by comparing the received UL CAPC value with the DL CAPC value for downlink data. The DL CAPC value may be selected based on the QoS requirements of the downlink data. If the DL CAPC value is lower than or equal to the UL CAPC value, then downlink data is allowed to be transmitted in the UE-initiated COT. If the DL CAPC value is higher than the UL CAPC value, then downlink data is allowed to be transmitted in the UE-initiated COT.

[0055] In some embodiments, the BS transmits downlink data in the UE-initiated COT without comparing the UL CAPC value with the DL CAPC value. If so, it is not necessary for the UE to transmit the UL CAPC to the BS. In some cases, reporting of the UL CAPC value is not supported; the UE does not report the UL CAPC value to the BS; or the BS does not successfully receive the UL CAPC value from the UE. If so, the BS can at least transmit a downlink signal with the lowest CAPC value (e.g., SS / PBCH, GC-PDCCH, SIB on PDSCH, periodic PDCCH, periodic CSI-RS, downlink feedback indication for UL configured grant transmission, or other UE-specific DCI, such as DL grant or UL grant). It is reasonable to assume that the above DL transmission has a relatively short duration. The duration of the above DL transmission plus the duration of the scheduled PUSCH does not exceed the MCOT corresponding to the lowest CAPC value, for example, for a CAPC value of 1, the MCOT is 2ms.

[0056] In operation 418, if downlink data is transmitted in the COT initiated by the UE, the BS performs the LBT Cat.2 procedure. The LBT Cat.2 procedure is simpler than the LBT Cat.4 procedure, so the BS can use less time to complete the LBT procedure. Please refer again Figure 2 .like Figure 2 As depicted in , the gap 206 between the time frame 204 and the time frame 208 is used for the BS to perform the LBT Cat.2 procedure, and thus the gap 206 can be regarded as a UL to DL switching point. In general, the gap 206 will not be shorter than 25us or 16us, so as to perform LBT Cat.2 with a sensing interval of 25us or with a sensing interval of 16us. The exact number of blanked symbols depends on the subcarrier spacing. If a subcarrier spacing of 15kHz or a subcarrier spacing of 30kHz is applied, at least the last symbol of the last PUSCH is blanked for the BS to perform LBT Cat.2. If a subcarrier spacing of 60kHz is applied, at least the last two symbols of the last PUSCH are blanked. If a subcarrier spacing of 120kHz is applied, at least the last four symbols of the last PUSCH are blanked. In operation 420, after completing the LBT procedure, the BS transmits downlink data.

[0057] It can be imagined that Figure 4 The order in which operations 402-420 are performed is not limited in the embodiments shown in FIG. 4. For example, operation 410 may be performed after operation 412 is completed. A person skilled in the art may change the order of operations 402-420 based on design choices. A person skilled in the art may also delete Figure 4Some operations shown in the figure, especially one or more operations drawn with dashed lines, are removed to improve time efficiency, reduce system workload or for other purposes.

[0058] Figure 5 A flow chart illustrating an exemplary procedure for sharing a UE-initiated COT for a scheduled PUSCH with a base station according to some embodiments of the present application. Figure 5 The operation in is similar to Figure 4 The operation is the same as in the previous example, except that the UL CAPC value is determined by the BS instead of the UE.

[0059] In operation 502, the BS may transmit a COT sharing requested indicator to the UE in order to request the UE to share the UE-initiated COT with the BS for downlink transmission. In a preferred embodiment, the COT sharing requested indicator is a one-bit indicator included in a DCI field, such as a UL grant. It can be envisioned that the DCI is used to schedule one or more PUSCHs for uplink data transmission in the UE-initiated COT. Therefore, the BS may dynamically request the UE to share the UE-initiated COT for downlink transmission.

[0060] In operation 504, the BS may transmit another indicator to the UE, the other indicator indicating the duration requested for the downlink transmission. In a preferred embodiment, such an indicator may also be included in a field of the DCI. The requested duration may be indicated as a number of time slots or a number of symbols or a combination of a number of time slots and a number of symbols. In another embodiment, the duration requested for the downlink transmission may be configured by RRC signaling. For example, the requested duration may be determined from a candidate group consisting of, for example, 2 symbols, 3 symbols, 4 symbols, 8 symbols, and 12 symbols; 1 time slot, 2 time slots, 4 time slots, 6 time slots, and 8 time slots; and so on.

[0061] In some embodiments, operation 504 may be omitted. For example, the duration of the downlink transmission may be preconfigured or fixed in the specification, and thus an indicator of the requested DL duration need not be transmitted to the UE.

[0062] In operation 506, the BS may select a UL CAPC value from a set of predefined CAPC values, such as the CAPC values ​​defined in Table 4.2.1-1 in TS37.213 mentioned above. In a preferred embodiment, the BS may select the UL CAPC value based on the sum of the duration required to transmit uplink data and the duration requested for downlink transmission. The BS may first select the shortest MCOT that can accommodate both UL transmission and DL transmission from a set of predefined CAPC values, and then further determine the UL CAPC value based on Table 4.2.1-1 and the selected COT.

[0063] For example, if the duration required to transmit uplink data is 2ms and the duration requested for downlink transmission is 1ms, the COT initiated by the UE has at least 3ms in order to accommodate both the duration of UL transmission and the duration of DL transmission. As shown in Table 4.2.1-1, a CAPC value of "1" corresponds to a maximum COT (MCOT) of 2ms; a CAPC value of "2" corresponds to a MCOT of 4ms; a CAPC value of "3" corresponds to a MCOT of 6ms or 10ms; and a CAPC value of "4" also corresponds to a MCOT of 6ms or 10ms. Therefore, the BS will select a CAPC value of "2" to perform the LBT Cat.4 procedure, for example, selecting a MCOT of 4ms, in order to ensure that the initiated COT can accommodate both the duration of UL transmission and the duration of DL transmission.

[0064] In operation 508, the BS then transmits the selected UL CAPC value to the UE. The selected UL CAPC value may be included in a field of a DCI used to schedule one or more PUSCHs, e.g., a UL grant, to transmit uplink data in a COT initiated by the UE. In some embodiments, the UL CAPC value may be transmitted to the UE in the same DCI as the DCI used to transmit the COT sharing requested indicator. In this case, operation 502 for transmitting the COT sharing requested indicator and operation 508 for transmitting the UL CAPC value may be combined.

[0065] In operation 512, after receiving the COT sharing requested indicator and the UL CAPC value, the UE performs the LBT Cat.4 procedure with the received CAPC value to initiate the COT to transmit the scheduled PUSCH. Thereafter, in operation 514, the UE transmits the PUSCH in the COT. The remaining COT may be shared with the BS for DL ​​transmission.

[0066] In operation 514, the UE may transmit information other than the uplink data to the BS. A one-bit indicator may also be included in the UCI. The one-bit indicator is a COT sharing indicator indicating whether the UE agrees to share the COT. In another embodiment, the one-bit indicator included in the UCI may indicate whether the UL to DL sharing is successful, because in some cases the UE cannot comply with the BS's request for sharing the COT.

[0067] In operation 516, after receiving the PUSCH transmission, the BS determines whether downlink data can be transmitted in the UE-initiated COT. The BS may determine whether to share the UE-initiated COT with the BS based on the value of the COT sharing indicator received in operation 514. In some other embodiments, the BS may determine whether downlink data can be transmitted in the UE-initiated COT by comparing the UL CAPC value with the DL CAPC value for downlink data. The DL CAPC value may be selected based on the QoS requirements of the downlink data. If the DL CAPC value is lower than or equal to the UL CAPC value, then downlink data is allowed to be transmitted in the UE-initiated COT. If the DL CAPC value is higher than the UL CAPC value, then downlink data is not allowed to be transmitted in the UE-initiated COT.

[0068] In some embodiments, the BS transmits downlink data in the UE-initiated COT without comparing the UL CAPC value with the DL CAPC value. The BS may transmit at least a downlink signal with the lowest CAPC value (e.g., SS / PBCH, GC-PDCCH, SIB on PDSCH, periodic PDCCH, periodic CSI-RS, downlink feedback indication for UL configured grant transmission, or other UE-specific DCI, such as DL grant or UL grant). It is reasonable to assume that the above DL transmissions have a fairly short duration. The duration for transmitting the above signals plus the scheduled PUSCH duration does not exceed the MCOT corresponding to the lowest CAPC value, for example, for a CAPC value of 1, the MCOT is 2ms.

[0069] In operation 518, if downlink data is transmitted in the COT initiated by the UE, the BS performs the LBT Cat.2 procedure. The LBT Cat.2 procedure is simpler than the LBT Cat.4 procedure, so the BS can use less time to complete the LBT procedure. Please refer again Figure 2 .like Figure 2As depicted in , the gap 206 between the time frame 204 and the time frame 208 is used for the BS to perform the LBT Cat.2 procedure, and thus the gap 206 can be viewed as a UL to DL switching point. In general, the gap 206 will be shorter than 25us or 16us in order to perform LBT Cat.2 with a sensing interval of 25us or with a sensing interval of 16us. The exact number of blanked symbols depends on the subcarrier spacing. If a subcarrier spacing of 15kHz or a subcarrier spacing of 30kHz is applied, at least the last symbol of the last PUSCH is blanked for the BS to perform LBT Cat.2. If a subcarrier spacing of 60kHz is applied, at least the last two symbols of the last PUSCH are blanked. If a subcarrier spacing of 120kHz is applied, at least the last four symbols of the last PUSCH are blanked. In operation 520, after completing the LBT procedure, the BS transmits downlink data.

[0070] It can be imagined that Figure 5 The order of operations 502-520 is not limited in the embodiment shown in FIG. For example, operation 504 may be performed after operation 508; and operation 516 may be performed earlier, for example, before operation 508 or 514. A person skilled in the art may change the order of operations 502-520 based on design choices. A person skilled in the art may also delete Figure 5 Some operations shown in , especially one or more operations drawn with dashed lines, or some operations, such as operations 502 and 508, may be combined to improve time efficiency, reduce system workload or for other purposes.

[0071] Figure 6 A flowchart of an exemplary procedure for sharing a COT initiated by a UE for a configured authorized PUSCH with a base station according to some embodiments of the present application is illustrated. In operation 602, the BS may transmit a COT sharing requested indicator to the UE in order to request the UE to share the COT initiated by the UE with the BS for downlink transmission. In a preferred embodiment, the COT sharing requested indicator is a one-bit indicator included in downlink feedback information (DFI), and the line link feedback information corresponds to one or more configured authorized PUSCHs for transmitting uplink data. In another embodiment, the COT sharing requested indicator may be included in the DCI in order to activate one or more configured authorized PUSCHs to transmit uplink data. For configured grant type 2, the DCI has a CRC scrambled by the CS-RNTI. In another embodiment, the COT sharing requested indicator may be configured by radio resource control (RRC) signaling. Therefore, the BS may dynamically or semi-statically request the UE to share the COT initiated by the UE for downlink transmission.

[0072] In operation 604, the BS may transmit another indicator to the UE, the other indicator indicating the duration requested for downlink transmission. In a preferred embodiment, such an indicator may also be included in a DFI or DCI, the DFI corresponding to one or more configured authorized PUSCHs for transmitting uplink data, and the DCI is used to activate one or more configured authorized PUSCHs for transmitting uplink data. The requested duration may be indicated as a number of time slots or a number of symbols or a combination of a number of time slots and a number of symbols. In another embodiment, the duration requested for downlink transmission may be configured by RRC signaling. For example, the requested duration may be determined from a candidate group consisting of: for example, 2 symbols, 3 symbols, 4 symbols, 8 symbols, and 12 symbols; 1 time slot, 2 time slots, 4 time slots, 6 time slots, and 8 time slots; and so on.

[0073] In some embodiments, operation 604 may be omitted. For example, the duration of the downlink transmission may be preconfigured or fixed in the specification, and thus an indicator of the requested DL duration need not be transmitted to the UE.

[0074] In operation 606, upon receiving the COT sharing requested indicator, the UE may select a CAPC value from a set of predefined CAPC values, such as the CAPC values ​​defined in Table 4.2.1-1 in TS37.213 mentioned above. In a preferred embodiment, the UE may select a CAPC value based on the sum of the duration required to transmit uplink data and the duration requested for downlink transmission. The UE may first select the shortest MCOT that can accommodate both UL transmission and DL transmission from a set of predefined CAPC values, and then further determine the CAPC value based on Table 4.2.1-1 and the selected COT.

[0075] In another embodiment, the UE selects a CAPC value from a set of predefined CAPC values ​​based on the uplink data. It is contemplated that the CAPC value may be selected based on the quality of service (QoS) requirements of the uplink data, i.e., the lowest channel access priority level (i.e., the highest CAPC value) of the logical channel with data available for transmission. Since the requested duration of the DL transmission does not affect the determination of the CAPC value, it may not be necessary to inform the UE of the requested duration of the DL transmission. Therefore, in some embodiments, operation 604 may be omitted.

[0076] In operation 610, the UE determines whether the MCOT of the selected CAPC value is sufficient to accommodate both the duration of the UL transmission and the duration of the DL transmission. If the COT is determined based on both the duration of the UL transmission and the duration of the DL transmission, the operation of 610 may be omitted. If the COT is determined based on the UL transmission, operation 610 is preferred.

[0077] In operation 610, if the UE receives an indicator indicating that the requested duration of DL transmission or the duration of DL transmission is configured or fixed, then in operation 610, the UE may determine whether the MCOT of the selected UL CAPC value is sufficient to accommodate both the duration of UL transmission and the duration of DL transmission. If the MCOT of the selected UL CAPC value is insufficient to accommodate both the duration of UL transmission and the duration of DL transmission, the UE may adjust the duration for the configured granted PUSCH. Alternatively, the UE may transmit all configured granted PUSCHs and then share the remaining COT with the BS, even if the duration of the remaining COT is shorter than the requested duration of DL transmission. The mechanism for determining how the COT is distributed to uplink data and downlink data is similar to that for Figure 4 The mechanism of the embodiments in FIG. 1 is described below and therefore is not omitted here.

[0078] The UE then performs LBT Cat.4 procedure with the selected UL CAPC value to initiate a COT to transmit the configured granted PUSCH in operation 612. Thereafter, the UE transmits the PUSCH in the COT in operation 614. The remaining COT may be shared with the BS for DL ​​transmission.

[0079] In operation 614, the UE may transmit information other than uplink data to the BS. For example, the UE may transmit a selected UL CAPC value (hereinafter referred to as "UL CAPC value") to the BS. The UL CAPC value may be carried as uplink control information (UCI) on one of the configured grant PUSCHs (e.g., the first or last configured grant PUSCH, each configured grant PUSCH, or an associated PUCCH).

[0080] A one-bit indicator may also be included in the UCI. The one-bit indicator is a COT sharing indicator indicating whether the UE agrees to share the COT. In another embodiment, the one-bit indicator included in the UCI may indicate whether the requested downlink duration can be accommodated in the COT. In yet another embodiment, the one-bit indicator included in the UCI may indicate whether the UL to DL sharing is successful, because in some cases the UE cannot comply with the BS's request for COT sharing. In some embodiments, one or more of the above indicators and the UL CAPC value may be indicated separately in the UCI. In other embodiments, one or more of the above indicators may be jointly encoded using the UL CAPC value.

[0081] If the UL CAPC value is determined by using Table 4.2.1-1, then there are four candidate CAPC values. Therefore, at least two bits are required to indicate one of the four candidate CAPC values. In one embodiment, the two bits are attached on the scheduled PUSCH by puncturing certain resource elements (REs) immediately following the first DMRS for the PUSCH. In another embodiment, the two bits are multiplexed using the uplink shared channel (UL-SCH) on the PUSCH, for example, the modulated symbols of the two bits are pre-pended at the beginning of the modulated symbols of the UL-SCH, or the two bits are included in the MAC header or a new MAC CE. In yet another embodiment, the two bits are carried in the PUCCH after the PUSCH is configured to grant. In this embodiment, PUCCH format 0 or 1 can be used to transmit the two bits.

[0082] In operation 616, after receiving the PUSCH transmission, the BS determines whether downlink data can be transmitted in the UE-initiated COT. The BS may determine whether the UE-initiated COT is shared with the BS based on the value of the COT sharing indicator included in the UCI. In some other embodiments, the BS may determine whether downlink data can be transmitted in the UE-initiated COT by comparing the received UL CAPC value with the DL CAPC value for downlink data. The DL CAPC value may be selected based on the QoS requirements of the downlink data. If the DL CAPC value is lower than or equal to the UL CAPC value, then downlink data is allowed to be transmitted in the UE-initiated COT. If the DL CAPC value is higher than the UL CAPC value, then downlink data is not allowed to be transmitted in the UE-initiated COT.

[0083] In some embodiments, the BS transmits downlink data in the UE-initiated COT without comparing the UL CAPC value with the DL CAPC value. If so, it is not necessary for the UE to transmit the UL CAPC to the BS. In some cases, reporting of the UL CAPC value is not supported; the UE does not report the UL CAPC value to the BS; or the BS does not successfully receive the UL CAPC value from the UE. If so, the BS can at least transmit a downlink signal with the lowest CAPC value (e.g., SS / PBCH, GC-PDCCH, SIB on PDSCH, periodic PDCCH, periodic CSI-RS, downlink feedback indication for UL configured grant transmission, or other UE-specific DCI, such as DL grant or UL grant). It is reasonable to assume that the above DL transmission has a relatively short duration. The duration of the above DL transmission plus the duration of the configured grant PUSCH does not exceed the MCOT corresponding to the lowest CAPC value, for example, for a CAPC value of 1, the MCOT is 2ms.

[0084] In operation 618, if downlink data is transmitted in the COT initiated by the UE, the BS performs the LBT Cat.2 procedure. The LBT Cat.2 procedure is simpler than the LBT Cat.4 procedure, so the BS can use less time to complete the LBT procedure. Please refer again Figure 3 .like Figure 3 As depicted in , the gap 306 between time frame 304 and time frame 308 is used for the BS to perform the LBT Cat.2 procedure, and thus the gap 306 can be viewed as a UL to DL switching point. In general, the gap 306 will not be shorter than 25us or 16us in order to perform LBT Cat.2 with a sensing interval of 25us or with a sensing interval of 16us. The exact number of blanked symbols depends on the subcarrier spacing. If a subcarrier spacing of 15kHz or a subcarrier spacing of 30kHz is applied, at least the last symbol of the last PUSCH is blanked for the BS to perform LBT Cat.2. If a subcarrier spacing of 60kHz is applied, at least the last two symbols of the last PUSCH are blanked. If a subcarrier spacing of 120kHz is applied, at least the last four symbols of the last PUSCH are blanked. In operation 620, after completing the LBT procedure, the BS transmits downlink data.

[0085] It can be imagined that Figure 6 The order in which operations 602-620 are performed is not limited in the embodiments shown in FIG. 6. For example, operation 610 may be performed after operation 612 is completed. A person skilled in the art may change the order of operations 602-620 based on design choices. A person skilled in the art may also delete Figure 6Some operations shown in the figure, especially one or more operations drawn with dashed lines, are removed to improve time efficiency, reduce system workload or for other purposes.

[0086] Figure 7 A flow chart illustrating another exemplary procedure for sharing a UE-initiated COT for a configured granted PUSCH with a base station according to some embodiments of the present application. Figure 7 The operation in is similar to Figure 6 The operation is the same as in the previous example, except that the UL CAPC value is determined by the BS instead of the UE.

[0087] In operation 702, the BS may transmit a COT sharing requested indicator to the UE in order to request the UE to share the UE-initiated COT with the BS for downlink transmission. In a preferred embodiment, the COT sharing requested indicator is a one-bit indicator included in downlink feedback information (DFI), and the downlink feedback information corresponds to one or more configured granted PUSCHs for transmitting uplink data. In another embodiment, the COT sharing requested indicator may be included in the DCI in order to activate one or more configured granted PUSCHs for transmitting uplink data. For the configured grant type 2, the DCI has a CRC scrambled by the CS-RNTI. In another embodiment, the COT sharing requested indicator may be included in the radio resource control (RRC) signaling. Therefore, the BS may dynamically or semi-statically request the UE to share the UE-initiated COT for downlink transmission.

[0088] In operation 704, the BS may transmit another indicator to the UE, the other indicator indicating the duration requested for the downlink transmission. In a preferred embodiment, such an indicator may also be included in a DFI corresponding to one or more configured grants PUSCH for transmitting uplink data. The requested duration may be indicated as a number of time slots or a number of symbols or a combination of a number of time slots and a number of symbols. In another embodiment, the duration requested for the downlink transmission may be configured by RRC signaling. For example, the requested duration may be determined from a candidate group consisting of, for example, 2 symbols, 3 symbols, 4 symbols, 8 symbols, and 12 symbols; 1 time slot, 2 time slots, 4 time slots, 6 time slots, and 8 time slots; and so on.

[0089] In some embodiments, operation 704 may be omitted. For example, the duration of the downlink transmission may be preconfigured or fixed in the specification, and thus an indicator of the requested DL duration need not be transmitted to the UE.

[0090] In operation 706, the BS may select a UL CAPC value from a set of predefined CAPC values, such as the CAPC values ​​defined in Table 4.2.1-1 in TS37.213 mentioned above. In a preferred embodiment, the UE may select the UL CAPC value based on the sum of the duration required to transmit uplink data and the duration requested for downlink transmission. The BS may first select the shortest MCOT that can accommodate both UL transmission and DL transmission from a set of predefined CAPC values, and then further determine the UL CAPC value based on Table 4.2.1-1 and the selected COT.

[0091] In operation 708, the BS then transmits the selected UL CAPC value to the UE. In one embodiment, the selected UL CAPC value may be included in a field of a DFI or a DCI, the DFI corresponding to one or more configured granted PUSCHs for the UE to transmit uplink data, the DCI being used to activate the one or more configured granted PUSCHs for transmitting uplink data. In some embodiments, the UL CAPC value may be transmitted to the UE in the same DFI as the DFI used to transmit the COT sharing requested indicator. In this case, operation 702 for transmitting the COT sharing requested indicator and operation 708 for transmitting the UL CAPC value may be combined. In another embodiment, the selected UL CAPC value may be configured by radio resource control (RRC) signaling.

[0092] In operation 712, after receiving the COT sharing requested indicator and the UL CAPC value, the UE then performs the LBTCat.4 procedure to initiate the COT to transmit the configured granted PUSCH. Thereafter, in operation 714, the UE transmits the PUSCH in the COT. The remaining COT may be shared with the BS for DL ​​transmission.

[0093] In operation 714, the UE may transmit information other than the uplink data to the BS. For example, a one-bit indicator may be transmitted along with the configured grant PUSCH. The one-bit indicator may be a COT sharing indicator indicating whether the UE agrees to share the COT. In another embodiment, a one-bit indicator included in the UCI may indicate whether the UL to DL sharing is successful, because in some cases the UE will not comply with the BS's request to share the COT.

[0094] In operation 716, after receiving the PUSCH transmission, the BS determines whether downlink data can be transmitted in the UE-initiated COT. The BS may determine whether to share the UE-initiated COT with the BS based on the value of the COT sharing indicator received in operation 714. In some other embodiments, the BS may determine whether downlink data can be transmitted in the UE-initiated COT by comparing the UL CAPC value with the DL CAPC value for downlink data. The DL CAPC value may be selected based on the QoS requirements of the downlink data. If the DL CAPC value is lower than or equal to the UL CAPC value, then downlink data is allowed to be transmitted in the UE-initiated COT. If the DL CAPC value is higher than the UL CAPC value, then downlink data is not allowed to be transmitted in the UE-initiated COT.

[0095] In some embodiments, the BS transmits downlink data in the UE-initiated COT without comparing the UL CAPC value with the DL CAPC value. The BS may transmit at least a downlink signal with the lowest CAPC value (e.g., SS / PBCH, GC-PDCCH, SIB on PDSCH, periodic PDCCH, periodic CSI-RS, downlink feedback indication for UL configured grant transmission, or other UE-specific DCI, such as DL grant or UL grant). It is reasonable to assume that the above DL transmissions have a fairly short duration. The duration for transmitting the above signals plus the configured grant PUSCH duration does not exceed the MCOT corresponding to the lowest CAPC value, for example, for a CAPC value of 1, the MCOT is 2ms.

[0096] In operation 718, if downlink data is transmitted in the COT initiated by the UE, the BS performs the LBT Cat.2 procedure. The LBT Cat.2 procedure is simpler than the LBT Cat.4 procedure, so the BS can use less time to complete the LBT procedure. Please refer again Figure 3 .like Figure 3As depicted in , the gap 306 between the time frame 304 and the time frame 308 is used for the BS to perform the LBT Cat.2 procedure, and thus the gap 306 can be regarded as a UL to DL switching point. In general, the gap 306 will not be shorter than 25us or 16us, so as to perform LBT Cat.2 with a sensing interval of 25us or with a sensing interval of 16us. The exact number of blanked symbols depends on the subcarrier spacing. If a subcarrier spacing of 15kHz or a subcarrier spacing of 30kHz is applied, at least the last symbol of the last PUSCH is blanked for the BS to perform LBT Cat.2. If a subcarrier spacing of 60kHz is applied, at least the last two symbols of the last PUSCH are blanked. If a subcarrier spacing of 120kHz is applied, at least the last four symbols of the last PUSCH are blanked. In operation 720, after completing the LBT procedure, the BS transmits downlink data.

[0097] It can be imagined that Figure 7 The order of operations 702-720 is not limited in the embodiment shown in FIG. For example, operation 704 may be performed after operation 708; and operation 716 may be performed earlier, for example, between operations 708 or 714. A person skilled in the art may change the order of operations 702-720 based on design choices. A person skilled in the art may also delete Figure 5 Some operations shown in , especially one or more operations drawn with dashed lines, or some operations, such as operations 702 and 708, may be combined to improve time efficiency, reduce system workload or for other purposes.

[0098] It can be envisioned that there may be both UL-to-DL switching points and DL-to-UL switching points in the UE-initiated COT. Figure 8 The diagram illustrates a COT initiated by a UE with both UL to DL switching point and DL to UL switching point for a scheduled PUSCH and a configured granted PUSCH according to some embodiments of the present application. Figure 8 In FIG. 8 , a gap 806 between a time frame 804 and a time frame 808 is used for the BS to perform the LBT Cat.2 procedure, and a gap 810 between a time frame 808 and a time frame 812 is used for the UE to perform the LBT Cat.2 procedure.

[0099] There are at least two situations where two UL-DL switching points are useful. In the first situation, when the BS requests that the shared resources be used just for transmitting a periodic DL signal / channel, the UE may use the remaining COT after the BS finishes transmitting the periodic DL signal / channel. In the second situation, after the BS finishes transmitting PDCCH and PDSCH in the UE-initiated COT, the UE may use the remaining COT to transmit HARQ feedback corresponding to the received PDSCH. It is contemplated that the UE-initiated COT may include one or more DL-to-UL switching points and one or more UL-to-DL switching points and is therefore not affected by Figure 8 The embodiments shown in .

[0100] Fig. 9 The block diagram of a UE according to an embodiment of the present disclosure is illustrated. The UE may include a receiving circuit system, a processor, and a transmitting circuit system. In one embodiment, the UE further includes a non-transitory computer-readable medium having computer-executable instructions stored thereon. The processor is coupled to the non-transitory computer-readable medium, the receiving circuit system, and the transmitting circuit system. The computer-executable instructions can be programmed to utilize the receiving circuit system, the transmitting circuit system, and the processor to perform operations (e.g., Figure 4-7 That is, after executing the computer-executable instructions, the receiving circuit system may receive a first indicator from the BS, the first indicator requesting the UE to share the COT for downlink transmission within the COT, wherein the COT is initiated by the UE to transmit uplink data; the processor may determine the first CAPC value and initiate the COT by performing a channel access procedure using the first CAPC value; and the transmitting circuit system may transmit at least a portion of the uplink data to the BS in the COT.

[0101] Fig.10 A block diagram of a BS according to an embodiment of the present disclosure is depicted. The BS may include a receive circuit system, a processor, and a transmit circuit system. In one embodiment, the BS further includes a non-transitory computer-readable medium having computer-executable instructions stored thereon. The processor is coupled to the non-transitory computer-readable medium, the receive circuit system, and the transmit circuit system. The computer-executable instructions may be programmed to utilize the receive circuit system, the transmit circuit system, and the processor to perform operations (e.g., Figure 4-7 That is, after executing the computer executable instructions, the transmitting circuit system may transmit a first indicator to the UE, wherein the first indicator requests the UE to share the COT for downlink transmission within the COT, wherein the COT is initiated by the UE to transmit uplink data; and may receive uplink data from the UE receiving circuit system within the COT.

[0102] The methods of the present disclosure may be implemented on a programmed processor. However, the controller, flow chart or module may also be implemented on a general purpose or special purpose computer, a programmed microprocessor or microcontroller and peripheral integrated circuit components, an integrated circuit, a hardware electronic or logic circuit such as a discrete component circuit, a programmable logic device, etc. In general, any device capable of implementing a finite state machine of the flow charts shown in the various figures may be used to implement the processing functions of the present disclosure.

[0103] Although the present disclosure has been described using specific embodiments of the present disclosure, it is apparent that many alternatives, modifications, and variations are apparent to those skilled in the art. For example, the various components of the embodiments may be interchanged, added, or replaced in other embodiments. Moreover, all elements shown in each figure are not necessary for the operation of the disclosed embodiments. For example, a person skilled in the art of the disclosed embodiments will be able to proceed and use the teachings of the present disclosure by simply adopting the elements of the independent claims. Therefore, the embodiments of the present disclosure as set forth herein are intended to be illustrative and not restrictive. Various changes may be made without departing from the spirit and scope of the present disclosure.

[0104] In the present disclosure, for example, "first", "second" or the like related terms can be used only to distinguish an entity or action from another entity or action, and may not necessarily require or imply any actual such relationship or order between such entities or actions. The term "include" or any other variation thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements does not only include those elements, but may include other elements that are not explicitly listed or inherent to such procedures, methods, articles or equipment. In the absence of more restrictions, the elements starting with "a", "an" or the like do not exclude the presence of additional equivalent elements in the process, method, article or equipment including the elements. Moreover, the term "another" is defined as at least the second more. As used herein, the terms "include", "have" or the like are positioned as "include".

Claims

1. A method for wireless communication performed by a user equipment (UE) using an unlicensed spectrum, the method comprising: receiving (402) a first indicator from a base station BS, the first indicator requesting the UE to share a channel occupation time COT with the BS for downlink transmission within the COT, wherein the COT is initiated by the UE in order to transmit uplink data; Determining (406) a first channel access priority level CAPC value; initiating the COT by performing (412) a Type-1 channel access procedure using the first CAPC value; and At least a portion of the uplink data is transmitted (414) to the BS within the COT, the transmission comprising a configured granted uplink (UL) transmission.

2. The method according to claim 1, wherein the first indicator is included in one of the following items: downlink control information DCI, which schedules one or more physical uplink shared channels PUSCH to transmit the uplink data; downlink feedback information DFI, which corresponds to one or more configured authorized PUSCHs to transmit the uplink data; DCI, which is used to activate the one or more configured authorized PUSCHs to transmit the uplink data; or radio resource control RRC signaling.

3. The method of claim 1 , wherein determining the first CAPC value comprises: The first CAPC value is received from the BS.

4. The method of claim 3, wherein the first CAPC value is indicated in one of: downlink control information, DCI, which schedules one or more PUSCHs for transmitting the uplink data; downlink feedback information, DFI, which corresponds to one or more configured granted PUSCHs for transmitting the uplink data; or radio resource control, RRC signaling.

5. The method of claim 1 , wherein determining the first CAPC value comprises: The first CAPC value is selected from a set of predefined CAPC values ​​based on the uplink data.

6. The method according to claim 1, further comprising: A second indicator is received from the BS, the second indicator indicating a requested duration for the downlink transmission.

7. The method according to claim 6, wherein the second indicator is included in one of the following items: downlink control information DCI, which schedules one or more physical uplink shared channels PUSCH to transmit the uplink data; downlink feedback information DFI, which corresponds to one or more configured authorized PUSCHs to transmit the uplink data; DCI, which is used to activate the one or more configured authorized PUSCHs to transmit the uplink data; or radio resource control RRC signaling.

8. The method of claim 6, wherein the uplink data is prioritized in response to a duration of the COT being shorter than a sum of a duration required to transmit the uplink data and the duration requested for the downlink transmission.

9. The method according to claim 6, further comprising: receiving first signaling from the BS, the first signaling indicating which of the uplink data and the downlink transmission is to be prioritized, wherein in response to the duration of the COT being shorter than the sum of the duration required to transmit the uplink data and the duration requested for the downlink transmission and the uplink data being prioritized, all of the uplink data is transmitted in the COT; and wherein in response to the duration of the COT being shorter than the sum of the duration required to transmit the uplink data and the duration requested for the downlink transmission and the downlink transmission being prioritized, a portion of the uplink data is transmitted in the COT.

10. The method according to claim 6, further comprising: The first CAPC value is selected from a set of predefined CAPC values ​​based on a sum of a duration required to transmit the uplink data and the duration requested for the downlink transmission.

11. The method according to claim 1, further comprising: The first CAPC value is transmitted to the BS. 12 . The method according to claim 11 , wherein the first CAPC value is indicated by puncturing resource elements (REs) of a physical uplink shared channel (PUSCH) carrying the uplink data.

13. The method of claim 11, wherein the first CAPC value is multiplexed with an uplink shared channel (UL-SCH) carrying the uplink data.

14. The method of claim 11, wherein the first CAPC value is indicated in a Physical Uplink Control Channel (PUCCH). 15 . The method of claim 11 , wherein the first CAPC value is included in uplink control information (UCI) associated to a physical uplink shared channel (PUSCH) carrying the uplink data.

16. The method of claim 1, further comprising: A third indicator is transmitted to the BS, the third indicator indicating whether the COT is shared for the downlink transmission. 17 . The method according to claim 16 , wherein the third indicator is included in uplink control information (UCI) associated to a physical uplink shared channel (PUSCH) carrying the uplink data.

18. The method of claim 1, further comprising: A number of symbols immediately preceding the downlink transmission are blanked.

19. The method according to claim 18, wherein the shortest duration of the number of symbols is equal to 16 or 25 microseconds.

20. A method performed by a base station BS for wireless communication using an unlicensed spectrum, the method comprising: transmitting (402) a first indicator to a user equipment (UE), the first indicator requesting the UE to share a channel occupation time (COT) with a BS for downlink transmission within the COT, wherein the COT is initiated by the UE in order to transmit uplink data; and The uplink data is received (414) from the UE within the COT, the transmission comprising a configured granted uplink (UL) transmission.

21. A method according to claim 20, wherein the first indicator is included in one of the following items: downlink control information DCI, which schedules one or more physical uplink shared channels PUSCH for the UE to transmit the uplink data; downlink feedback information DFI, which corresponds to one or more configured authorized PUSCHs for the UE to transmit the uplink data; DCI, which is used to activate the one or more configured authorized PUSCHs for the UE to transmit the uplink data; or radio resource control RRC signaling.

22. The method of claim 20, further comprising: A first CAPC value is transmitted to the UE, wherein the UE initiates the COT using the first CAPC value.

23. The method of claim 22, wherein the first CAPC value is indicated in one of: downlink control information, DCI, which schedules one or more PUSCHs for the UE to transmit the uplink data; downlink feedback information, DFI, which corresponds to one or more configured granted PUSCHs for the UE to transmit the uplink data; or radio resource control, RRC signaling.

24. The method of claim 22, wherein the first CAPC value is selected from a set of predefined CAPC values ​​based on a sum of a duration required to transmit the uplink data and a duration requested for the downlink transmission.

25. The method of claim 20, further comprising: A second indicator is transmitted to the UE, the second indicator indicating a requested duration for the downlink transmission.

26. A method according to claim 25, wherein the second indicator is included in one of the following items: downlink control information DCI, which schedules one or more physical uplink shared channels PUSCH for the UE to transmit the uplink data; downlink feedback information DFI, which corresponds to one or more configured authorized PUSCHs for the UE to transmit the uplink data; DCI, which is used to activate the one or more configured authorized PUSCHs for the UE to transmit the uplink data; or radio resource control RRC signaling.

27. The method of claim 25, wherein the uplink data is prioritized in response to a duration of the COT being shorter than a sum of a duration required to transmit the uplink data and the duration requested for the downlink transmission.

28. The method of claim 25, further comprising: transmitting first signaling to the UE, the first signaling indicating which of the uplink data and the downlink transmission is to be prioritized, wherein in response to the duration of the COT being shorter than the sum of the duration required to transmit the uplink data and the duration requested for the downlink transmission and the uplink data being prioritized, all of the uplink data is transmitted in the COT; and wherein in response to the duration of the COT being shorter than the sum of the duration required to transmit the uplink data and the duration requested for the downlink transmission and the downlink transmission being prioritized, a portion of the uplink data is transmitted in the COT.

29. The method of claim 20, further comprising: A first CAPC value is received from the UE, wherein the UE initiates the COT using the first CAPC value.

30. The method according to claim 29, wherein the first CAPC value is indicated by puncturing resource elements (REs) of a physical uplink shared channel (PUSCH) carrying the uplink data.

31. The method of claim 29, wherein the first CAPC value is multiplexed with an uplink shared channel (UL-SCH) carrying the uplink data.

32. The method of claim 29, wherein the first CAPC value is indicated in a Physical Uplink Control Channel (PUCCH).

33. The method of claim 29, wherein the first CAPC value is included in uplink control information (UCI) associated to a physical uplink shared channel (PUSCH) carrying the uplink data.

34. The method of claim 20, further comprising: receiving a third indicator from the UE, the third indicator indicating whether to share the COT for the downlink transmission; In response to the third indicator indicating that the COT is to be shared for the downlink transmission, transmitting downlink data; and In response to the third indicator indicating that the COT will not be shared for the downlink transmission, the downlink data is not transmitted.

35. The method of claim 34, wherein the third indicator is included in uplink control information (UCI) associated to a physical uplink shared channel (PUSCH) carrying the uplink data.

36. The method of claim 20, further comprising: A number of symbols immediately preceding the downlink transmission are blanked.

37. The method of claim 36, wherein the shortest duration of the number of symbols is equal to 16 or 25 microseconds.

38. The method of claim 29, further comprising: determining a second CAPC value based on downlink data, wherein the downlink data is included in the downlink transmission; In response to the second CAPC value being less than or equal to the first CAPC value, transmitting the downlink data; and In response to the second CAPC value being greater than the first CAPC value, the downlink data is not transmitted.

39. A user equipment UE, comprising: at least one memory; as well as at least one processor coupled to the at least one memory and configured to cause the UE to: receiving (402) a first indicator from a base station BS, the first indicator requesting the UE to share a channel occupation time COT with the BS for downlink transmission within the COT, wherein the COT is initiated by the UE in order to transmit uplink data; Determining (406) a first channel access priority level CAPC value; initiating the COT by performing (412) a Type-1 channel access procedure using the first CAPC value; and At least a portion of the uplink data is transmitted (414) to the BS within the COT, the transmission comprising a configured granted uplink (UL) transmission.

40. A base station BS, comprising: at least one memory; as well as at least one processor coupled to the at least one memory and configured to cause the BS to: transmitting (402) a first indicator to a user equipment (UE), the first indicator requesting the UE to share a channel occupation time (COT) with the BS for downlink transmission within the COT, wherein the COT is initiated by the UE in order to transmit uplink data; and The uplink data is received (414) from the UE within the COT, the transmission comprising a configured granted uplink (UL) transmission.

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