Patent Description:
In some cases, a downlink control channel may be used to schedule downlink and uplink grants for a user equipment (UE). The downlink control channel may be transmitted according to search space sets, and may be monitored by the UE continuously while in a connected or active state. For example, UEs may monitor the control channel by decoding control channel candidates within the search space across one or more aggregation levels. Reduced capabilities for the UEs may result in an increase in aggregation level or decoding candidates, which may result in an undesirable amount of overhead and/or power consumption for the UEs.

<CIT> discloses a mobile communication system supporting uplink transmission using an unlicensed spectrum. Specifically, a user terminal is described which comprises a controller configured to perform LBT (Listen-Before-Talk) before the uplink transmission. The controller applies a first LBT scheme to the LBT, in response to reception of information indicating the first LBT scheme from a base station. The controller applies a second LBT scheme to the LBT, in response to reception of information indicating the second LBT scheme with a shorter LBT time interval than the first LBT scheme, from the base station.

<CIT> discloses a method for performing an uplink transmission to a base station by a user equipment through an unlicensed cell in a wireless communication system, including receiving an uplink grant that schedules the uplink transmission in at least one subframe from the base station; and performing the uplink transmission in the at least one subframe using at least one of a first type channel access or a second type channel access. The uplink transmission is performed using the second type channel access when all of the at least one subframe is included in a predetermined interval determined based on a downlink transmission through the unlicensed cell from the base station.

Preferred embodiments are defined by the subject-matter of the dependent claims.

Some user equipment (UE) that perform wireless communications may lack capabilities (e.g., a high enough processing or battery capacity) to support a full range of wireless communication features. For example, New Radio (NR) may support features related to high bandwidth or low latency communications. Some NR UEs, referred to as NR-light UEs, may be designed for simplified or lower cost implementations. However, some features of NR communications may disproportionately affect power consumption for NR-light UEs. For instance, when using physical downlink control channel (PDCCH) or downlink control information (DCI)-based dynamic scheduling to receive a physical downlink shared channel (PDSCH), NR-light UEs may experience increased overhead or increased power consumption as compared to other NR UEs. The NR-light UEs may experience the increased overhead or increased power consumption due to having narrower operation bandwidths, smaller numbers of transmit and receive antennas, a more relaxed time-line, or a combination of these. Additionally, if an NR-light UE is communicating in the unlicensed spectrum, the NR-light UE may experience greater overhead than when communicating in the licensed spectrum due to listen-before-talk (LBT) uncertainty.

To decrease overhead and/or power consumption in one or both scenarios, an NR-light UE may be configured to monitor for a PDSCH transmission from a base station over a set of periodically scheduled resources in an unlicensed spectrum without receiving a corresponding downlink (e.g., dynamic scheduling) grant. The PDSCH transmission may include a medium access control (MAC) control element (MAC-CE) that indicates a channel access configuration (e.g., an LBT configuration) for the UE to access the unlicensed spectrum. The UE may use the indicated channel access configuration to transmit a message (e.g., an acknowledgement (ACK)) to the base station. By receiving PDSCHs without a corresponding grant (e.g., via PDCCH or DCI), the UE may avoid the overhead and/or power consumption associated with monitoring and receiving grants via the PDCCH. Additionally or alternatively, by receiving a channel access configuration in the PDSCH, the UE may decrease overhead associated with communicating in the unlicensed spectrum.

Aspects of the disclosure are initially described in the context of a wireless communications system. Additional aspects of the disclosure are described in the context of an additional wireless communications system, a cluster scheme, and process flows. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to indication of listen-before-talk configuration for uplink communications.

<FIG> illustrates an example of a wireless communications system <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The wireless communications system <NUM> includes base stations <NUM>, UEs <NUM>, and a core network <NUM>. In some aspects, the wireless communications system <NUM> may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. In some cases, wireless communications system <NUM> may support enhanced broadband communications, ultra-reliable (e.g., mission critical) communications, low latency communications, or communications with low-cost and low-complexity devices.

In some aspects, a base station <NUM> may be movable and therefore provide communication coverage for a moving geographic coverage area <NUM>. In some aspects, different geographic coverage areas <NUM> associated with different technologies may overlap, and overlapping geographic coverage areas <NUM> associated with different technologies may be supported by the same base station <NUM> or by different base stations <NUM>.

In some aspects, a carrier may support multiple cells, and different cells may be configured according to different protocol types (e.g., machine-type communication (MTC), narrowband Internet-of-Things (NB-IoT), enhanced mobile broadband (eMBB), or others) that may provide access for different types of devices.

In some aspects, a UE <NUM> may also refer to a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or an MTC device, or the like, which may be implemented in various articles such as appliances, vehicles, meters, or the like.

In some aspects, M2M communication or MTC may include communications from devices that integrate sensors or meters to measure or capture information and relay that information to a central server or application program that can make use of the information or present the information to humans interacting with the program or application.

In some aspects half-duplex communications may be performed at a reduced peak rate.

In some aspects, wireless communications system <NUM> may support millimeter wave (mmW) communications between UEs <NUM> and base stations <NUM>, and EHF antennas of the respective devices may be even smaller and more closely spaced than UHF antennas.

In some aspects, base station <NUM> or UE <NUM> may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. For example, wireless communications system <NUM> may use a transmission scheme between a transmitting device (e.g., a base station <NUM>) and a receiving device (e.g., a UE <NUM>), where the transmitting device is equipped with multiple antennas and the receiving device is equipped with one or more antennas.

In one aspect, a base station <NUM> may use multiple antennas or antenna arrays to conduct beamforming operations for directional communications with a UE <NUM>. For instance, some signals (e.g. synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted by a base station <NUM> multiple times in different directions, which may include a signal being transmitted according to different beamforming weight sets associated with different directions of transmission. Transmissions in different beam directions may be used to identify (e.g., by the base station <NUM> or a receiving device, such as a UE <NUM>) a beam direction for subsequent transmission and/or reception by the base station <NUM>.

Some signals, such as data signals associated with a particular receiving device, may be transmitted by a base station <NUM> in a single beam direction (e.g., a direction associated with the receiving device, such as a UE <NUM>). In some aspects, the beam direction associated with transmissions along a single beam direction may be determined based at least in in part on a signal that was transmitted in different beam directions. For example, a UE <NUM> may receive one or more of the signals transmitted by the base station <NUM> in different directions, and the UE <NUM> may report to the base station <NUM> an indication of the signal it received with a highest signal quality, or an otherwise acceptable signal quality. Although these techniques are described with reference to signals transmitted in one or more directions by a base station <NUM>, a UE <NUM> may employ similar techniques for transmitting signals multiple times in different directions (e.g., for identifying a beam direction for subsequent transmission or reception by the UE <NUM>), or transmitting a signal in a single direction (e.g., for transmitting data to a receiving device).

In some aspects a receiving device may use a single receive beam to receive along a single beam direction (e.g., when receiving a data signal). The single receive beam may be aligned in a beam direction determined based on listening according to different receive beam directions (e.g., a beam direction determined to have a highest signal strength, highest signal-to-noise ratio, or otherwise acceptable signal quality based on listening according to multiple beam directions).

A carrier may be associated with a pre-defined frequency channel (e.g., an evolved universal mobile telecommunication system terrestrial radio access (E-UTRA) absolute radio frequency channel number (EARFCN)), and may be positioned according to a channel raster for discovery by UEs <NUM>. In some aspects, signal waveforms transmitted over a carrier may be made up of multiple sub-carriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM)).

The organizational structure of the carriers may be different for different radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR). In some aspects (e.g., in a carrier aggregation configuration), a carrier may also have acquisition signaling or control signaling that coordinates operations for other carriers.

In some aspects, control information transmitted in a physical control channel may be distributed between different control regions in a cascaded manner (e.g., between a common control region or common search space and one or more UE-specific control regions or UE-specific search spaces).

A carrier may be associated with a particular bandwidth of the radio frequency spectrum, and in some aspects the carrier bandwidth may be referred to as a "system bandwidth" of the carrier or the wireless communications system <NUM>. In some aspects, each served UE <NUM> may be configured for operating over portions or all of the carrier bandwidth.

Devices of the wireless communications system <NUM> (e.g., base stations <NUM> or UEs <NUM>) may have a hardware configuration that supports communications over a particular carrier bandwidth, or may be configurable to support communications over one of a set of carrier bandwidths. In some aspects, the wireless communications system <NUM> may include base stations <NUM> and/or UEs <NUM> that support simultaneous communications via carriers associated with more than one different carrier bandwidth.

Wireless communications system <NUM> may support communication with a UE <NUM> on multiple cells or carriers, a feature which may be referred to as carrier aggregation or multi-carrier operation.

In some cases, an eCC may utilize a different symbol duration than other component carriers, which may include use of a reduced symbol duration as compared with symbol durations of the other component carriers.

Wireless communications system <NUM> may be an NR system that may utilize any combination of licensed, shared, and unlicensed spectrum bands, among others. The flexibility of eCC symbol duration and subcarrier spacing may allow for the use of eCC across multiple spectrums. In some aspects, NR shared spectrum may increase spectrum utilization and spectral efficiency, specifically through dynamic vertical (e.g., across the frequency domain) and horizontal (e.g., across the time domain) sharing of resources.

A wireless network, for example a wireless local area network (WLAN), such as a Wi-Fi (i.e., Institute of Electrical and Electronics Engineers (IEEE) <NUM>) network may include an access point (AP) that may communicate with one or more wireless or mobile devices. The AP may be coupled to a network, such as the Internet, and may enable a mobile device to communicate via the network (or communicate with other devices coupled to the access point). A wireless device may communicate with a network device bi-directionally. For example, in a WLAN, a device may communicate with an associated AP via downlink (e.g., the communication link from the AP to the device) and uplink (e.g., the communication link from the device to the AP). A wireless personal area network (PAN), which may include a Bluetooth connection, may provide for short range wireless connections between two or more paired wireless devices. For example, wireless devices such as cellular phones may utilize wireless PAN communications to exchange information such as audio signals with wireless headsets.

A UE <NUM> may monitor for a transmission over a set of periodically scheduled resources of a downlink shared channel in an unlicensed spectrum. Monitoring the set of periodically scheduled resources of the downlink shard channel may be performed in place of monitoring of a downlink control channel. The UE <NUM> may receive the transmission, where the transmission indicates a channel access configuration (e.g., a listen-before-talk (LBT) configuration) for accessing the unlicensed spectrum. In some cases, the transmission may include a medium access control (MAC) control element (MAC-CE) that indicates the channel access configuration. The transmission may additionally indicate at least one uplink channel over which the UE <NUM> may transmit a message and/or a channel occupancy time (COT) associated with a successful acquisition of the unlicensed spectrum by the base station. The UE <NUM> may transmit a message (e.g., an acknowledgement (ACK)) based on the channel access configuration.

<FIG> illustrates an example of a wireless communications system <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. In some aspects, wireless communications system <NUM> may implement aspects of wireless communications system <NUM>. For instance, wireless communications system <NUM> may include a base station <NUM>-a, which may be an example of a base station <NUM> as described with reference to <FIG>, and a UE <NUM>-a, which may be an example of a UE <NUM> as described with reference to <FIG>. UE <NUM>-a may perform uplink communications with base station <NUM>-a via communication link <NUM>-a and base station <NUM>-b may perform downlink communications with UE <NUM>-a via communication link <NUM>-b. In some cases, communication link <NUM>-a and communication link <NUM>-b may span a same set of frequencies.

UE <NUM>-a may be configured to monitor or listen at periodic instances <NUM> for receiving a PDSCH transmission <NUM>. In some cases, the UE <NUM>-a may stop or suppress monitoring of a control channel when configured to monitor for periodic instances <NUM> of the PDSCH. The periodic instances <NUM> may be configured via radio resource control (RRC)signaling and may include periodically scheduled resources repeating with a period <NUM>. In some cases, the PDSCH transmission <NUM> may contain UE data <NUM> for UE <NUM>-a and a MAC-CE <NUM> containing information for how to transmit ACKs <NUM> corresponding to the UE data <NUM> over an uplink (e.g., communication link <NUM>-a). Such information may include an indication of which channel to transmit the ACKs <NUM> over and the associated channel access configuration (e.g., an LBT configuration) used to transmit the ACKs <NUM>. In some aspects, the MAC-CE <NUM> may include a number of bits (e.g., <NUM> bits) for a PDSCH-to-ACK feedback timing indicator whose value may be an index to a table of numbers that may be predetermined or configured.

The indicated channel for carrying ACKs <NUM> may be a physical uplink control channel (PUCCH), a configured-grant (CG) PUSCH, a random access channel (RACH), or a combination of channels. If the MAC-CE <NUM> indicates more than one channel, UE <NUM>-a may choose one channel in the set (e.g., just PUCCH, PUSCH, or the RACH) or may transmit multiple duplicates of the ACK <NUM> over multiple of the channels (e.g., one duplicate over PUCCH and one duplicate over CG PUSCH). If UE <NUM>-a uses the RACH to transmit an ACK <NUM>, UE <NUM>-a may transmit the ACK <NUM> with a pre-configured preamble that is contention-free and may do so as part of a <NUM>-step RACH procedure. UE <NUM>-a may choose to use the RACH if it is not able to maintain synchronization for the uplink (e.g., due to a inter-data-packet interval longer than a threshold value). The PUCCH resource indicator within the MAC-CE <NUM> may consist of <NUM> bits whose value may be an index to a table of numbers that may be predetermined or configured; the CG-PUSCH resource indicator within the MAC-CE <NUM> may consist of <NUM> bits, which may indicate up to <NUM> configurations; and the preamble index for contention-free <NUM>-step RACH within the MAC-CE <NUM> may consist of <NUM> bits.

If UE <NUM>-a lacks a capability to perform advanced adaptive HARQ, UE <NUM>-a may use a simplified implementation. For instance, base station <NUM>-a may transmit a first PDSCH transmission <NUM> containing UE data <NUM> and MAC-CE <NUM> that specifies where to transmit an ACK <NUM>. If UE <NUM>-a does not receive the PDSCH transmission <NUM> or if base station <NUM>-a fails to receive the corresponding ACK <NUM>, base station <NUM>-a may transmit another PDSCH transmission <NUM> containing the same UE data <NUM> as that of the original PDSCH transmission <NUM> but with a different MAC-CE <NUM>.

For operation in unlicensed spectrum, base station <NUM>-a may check out a COT and may provide an indication of when the COT ends to UE <NUM>-a via the MAC-CE <NUM>. The process of base station <NUM>-a checking out the COT may be referred to as a base station-initiated COT. UE <NUM>-a may use the indication to access the uplink channel before the end of indicated COT (e.g., using one-shot LBT). Generally, one-shot LBT may refer to CAT1 or CAT2 LBT, which may be in load-based-equipment (LBE), or frame-based equipment (FBE). In some cases, the COT ending indication may include <NUM> bits and may indicate a number of subframes.

Assuming, for instance, that UE <NUM>-a does not support back-off based LBT (e.g., a CAT4 LBT), base station <NUM>-a may send a MAC-CE <NUM> if the uplink channel may be accessed using one-shot LBT and may not send the MAC-CE <NUM> otherwise (e.g., if an amount of time left to access the uplink channel is below a threshold amount or if the COT does not support the uplink channel for the ACK <NUM>). In the case that UE <NUM>-a supports back-off based LBT, base station <NUM>-a may send MAC-CE <NUM> without regard to whether or not the uplink channel may be accessed using one-shot LBT. In such a case, UE <NUM>-a may access the uplink channel using a back-off based LBT procedure and may transmit an ACK <NUM> upon accessing the uplink channel.

If UE <NUM>-a fails to receive a MAC-CE <NUM> with a first PDSCH transmission <NUM> (e.g., due to the uplink channel being inaccessible with one-shot LBT before the end of the base-station initiated COT), UE <NUM>-a may wait for a next configured instant for a second PDSCH transmission <NUM> containing a MAC-CE <NUM> before accessing the uplink channel. The next configured instant may be within a different COT from the COT in which the first PDSCH transmission <NUM> was sent. The second PDSCH transmission <NUM> may not contain UE data <NUM>, as UE <NUM>-a may use the MAC-CE <NUM> of the second PDSCH transmission <NUM> to transmit an ACK <NUM> for the UE data <NUM> contained within the first PDSCH transmission <NUM>.

In other cases, UE <NUM>-a may check out a COT (i.e., a UE-initiated COT) and may provide a request to base station <NUM>-a to transmit a PDSCH transmission <NUM>. In some cases, UE <NUM>-a transmitting the request to base station <NUM>-a may be referred to as polling. UE <NUM>-a may transmit the request if the COT is of a predetermined type (e.g., a CAT4 LBT-based COT from a CG uplink) and may refrain from transmitting the request elsewise. The request may be a one-bit indicator.

Upon receiving the request, base station <NUM>-a may transmit a PDSCH transmission <NUM> over resources at least partially different from periodic instances <NUM> and which may be within the COT. In some cases, the request may trigger multiple base stations <NUM> to perform joint or simultaneous transmission of a PDSCH transmission <NUM>. For instance, base station <NUM>-a and another base station <NUM> may receive the request and may both transmit a respective PDSCH transmission <NUM> to UE <NUM>-a. UE <NUM>-a may receive a PDSCH transmission <NUM> from base station <NUM>-a and may transmit an ACK <NUM> for data received from base station <NUM>-a. In some cases, the data may have been received in a prior PDSCH transmission <NUM> which included UE data <NUM>. In such cases, the PDSCH transmission <NUM> may include a MAC-CE <NUM> but not UE data <NUM>, as the MAC-CE <NUM> may indicate a channel for transmitting ACK <NUM> for the UE data <NUM> received in the prior PDSCH transmission <NUM>. Alternatively, the current PDSCH transmission <NUM> may contain both a MAC-CE <NUM> and UE data <NUM>, in which UE <NUM>-a may transmit an ACK <NUM> for the UE data <NUM> received in the current PDSCH transmission <NUM>. If UE <NUM>-a still has the UE-initiated COT checked out, UE <NUM>-a may transmit the ACK <NUM> within the UE-initiated COT. Alternatively, UE <NUM>-a may access an uplink channel indicated by the MAC-CE <NUM> and may transmit the ACK <NUM> in the uplink channel indicated by the MAC-CE <NUM>.

In some cases, UE <NUM>-a may receive MAC-CE <NUM> for purposes besides transmitting ACKs. For instance, if UE <NUM>-a receives a PDSCH transmission <NUM> in a gNB-initiated COT, such as described herein, the COT-ending indicator of the MAC-CE <NUM> may be used for triggering within-COT channel access for PUCCH, configured-grant PUSCH, or physical random access channel (PRACH) for non-ACK purposes. Additionally or alternatively, a MAC-CE <NUM> may carry a downlink feedback indication (DFI) for a CG uplink. The DFI may be carried in lieu of the channel access configuration and may be carried with UE data <NUM> or may be carried alone if the PDSCH transmission does not include UE data <NUM>. The DFI may include, for example, an indicator for an aperiodic feedback transmission or other information related to transmission over the CG uplink. There may be cases where the DFI and the channel access configuration may be carried within the same MAC-CE <NUM>.

In general, UE <NUM>-a receiving MAC-CE <NUM> over PDSCH transmission <NUM> at pre-configured periodic instances <NUM> may enable UE <NUM>-a to have a larger coding gain as compared to having separate PDCCHs and PDSCH transmissions <NUM>. The PDSCH transmission <NUM> containing the MAC-CE <NUM> may have more bits than either a PDCCH or a PDSCH transmission alone and may thus be able to be encoded to achieve a higher coding gain. Additionally, base stations <NUM> communicating with UE <NUM>-a may be able to use advanced downlink coordinated multi-point (CoMP) for better performance since PDSCH transmission <NUM> is arranged at pre-configured instants.

<FIG> illustrates an example of a cluster scheme <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. In some aspects, cluster scheme <NUM> may implement aspects of wireless communications system <NUM>. For instance, cluster scheme <NUM> may be implemented by a base station <NUM> and/or a UE <NUM> as described with reference to <FIG>. In some cases, multiple transmission time intervals (TTIs) <NUM> may be arranged into a cluster <NUM>. For instance TTIs <NUM>-a, <NUM>-b, and <NUM>-c may be arranged into a cluster <NUM>. Each cluster <NUM> may represent a periodic instance <NUM> as described with reference to <FIG>.

In some cases, a base station <NUM> may perform LBT to acquire a channel in the unlicensed spectrum before TTI <NUM>-a, TTI <NUM>-b, or TTI <NUM>-c. If a UE <NUM> receives a PDSCH transmission <NUM> within a TTI <NUM> during the associated COT (e.g., TTI <NUM>-a if base station <NUM> acquires the channel before TTI <NUM>-a) and successfully decodes the PDSCH transmission <NUM>, the UE <NUM> may cease from monitoring for PDSCH transmissions <NUM> in the remaining TTIs <NUM> (e.g., TTIs <NUM>-b and <NUM>-c) of the cluster <NUM>. However, if the PDSCH transmission <NUM> contains a MAC-CE <NUM>, the UE <NUM> may continue to monitor for PDSCH transmissions <NUM> in the remaining TTIs <NUM> (e.g., the remaining TTIs <NUM> within the COT and/or within the cluster <NUM>). For instance, the MAC-CE <NUM> may indicate over which TTI <NUM> the UE <NUM> is to monitor for the PDSCH transmission <NUM> or may simply indicate that the UE <NUM> is to monitor for additional PDSCH transmissions <NUM> in the remaining TTIs <NUM>.

For the latter case, after receiving an additional PDSCH transmission <NUM> in an additional TTI <NUM> (e.g., TTI <NUM>-b), the UE <NUM> may check the MAC-CE <NUM>, if applicable, of the additional PDSCH transmission <NUM> to determine whether or not to continue to monitor for PDSCH transmissions <NUM> in the remaining TTIs <NUM>. For instance, if the UE <NUM> receives an additional PDSCH transmission <NUM> in TTI <NUM>-b, the UE <NUM> may check the MAC-CE <NUM> to determine whether or not to monitor for a PDSCH transmission <NUM> in TTI <NUM>-c. Alternatively, the UE <NUM> may continue monitoring for PDSCH transmissions <NUM> in the remaining TTIs <NUM> (e.g., the remaining TTIs <NUM> within the COT and/or within the cluster <NUM>) after receiving an additional PDSCH transmission <NUM> without making the determination of whether or not to continue monitoring.

<FIG> illustrates an example of a process flow <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. In some aspects, process flow <NUM> may implement aspects of wireless communications system <NUM>. For instance, process flow <NUM> may include a base station <NUM>-b, which may be an example of a base station <NUM> as described with reference to <FIG>, and a UE <NUM>-b, which may be an example of a UE <NUM> as described with reference to <FIG>.

At <NUM>, UE <NUM>-b may perform a channel access procedure on the unlicensed spectrum. In some cases, the channel access procedure may include an LBT procedure with random back off for acquiring a CG uplink channel. At <NUM>, UE <NUM>-b may identify a COT associated with a successful acquisition of the unlicensed spectrum for performing communications based on the channel access procedure. At <NUM>, UE <NUM>-b may transmit a request for a transmission (e.g., a PDSCH transmission <NUM>) to base station <NUM>-b. Base station <NUM>-b may receive the request.

At <NUM>, base station <NUM>-b may transmit a transmission. The transmission may indicate a channel access configuration (e.g., an LBT configuration) for UE <NUM>-b for the unlicensed spectrum. In some cases, the transmission may include a control element (e.g., a MAC-CE <NUM>) that indicates the channel access configuration. In some cases, the transmission may not include data for UE <NUM>-b (e.g., UE data <NUM>).

The transmission may be received based on the request transmitted at <NUM> and may be received during the COT associated with the successful acquisition by UE <NUM>-b. Additionally, a second transmission may be received from another base station <NUM> during the COT associated with the successful acquisition by UE <NUM>-b. In some cases, the transmission may be received at least partially over resources outside of a set of periodically scheduled resources.

At <NUM>, UE <NUM>-b may transmit a message (e.g., an ACK) based on the channel access configuration. UE <NUM>-b may use an uplink channel indicated by the transmission (e.g., by the MAC-CE). The at least one uplink channel may include an uplink control channel, a CG uplink shared channel, a RACH, or a combination thereof. If the at least one uplink channel includes the RACH, UE <NUM>-b may transmit a pre-assigned preamble to base station <NUM>-b based on the at least one uplink channel including the RACH. If the at least one uplink channel includes two or more uplink channels, UE <NUM>-b may select one of them for transmitting the message. Alternatively, UE <NUM>-b may use multiple of the two or more uplink channels to transmit duplicates of the message.

<FIG> illustrates an example of a process flow <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. In some aspects, process flow <NUM> may implement aspects of wireless communications system <NUM>. For instance, process flow <NUM> may include a base station <NUM>-c, which may be an example of a base station <NUM> as described with reference to <FIG>, and a UE <NUM>-c, which may be an example of a UE <NUM> as described with reference to <FIG>.

At <NUM>, base station <NUM>-c may perform a channel access procedure on the unlicensed spectrum. At <NUM>, base station <NUM>-c may identify a COT associated with a successful acquisition of the unlicensed spectrum for performing communications based on the channel access procedure.

At <NUM>, UE <NUM>-c may monitor for a transmission (e.g., a PDSCH transmission <NUM>) over a set of periodically scheduled resources (e.g., periodic instances <NUM>) of a downlink shared channel in an unlicensed spectrum.

At <NUM>, base station <NUM>-c may transmit the transmission over at least one of the set of periodically scheduled resources for the UE of the downlink shared channel in the unlicensed spectrum. The transmission may indicate a channel access configuration (e.g., an LBT configuration) for UE <NUM>-c for the unlicensed spectrum. In some cases, the transmission may include a control element (e.g., a MAC-CE <NUM>) that indicates the channel access configuration. Additionally, the transmission may include data for UE <NUM>-c (e.g., UE data <NUM>).

In some aspects, the control element may indicate a COT associated with the transmission. The channel access configuration may indicate a one-shot channel access configuration. In some cases, UE <NUM>-b may receive a second transmission from base station <NUM>-b that indicates a DFI. The second transmission may include data for UE <NUM>-b (e.g., UE data <NUM>).

In some cases, each of the set of periodically scheduled resources may include a set of TTIs (e.g., TTIs <NUM>). In such cases, UE <NUM>-c may receive the transmission over a first TTI of the set of TTIs of a periodically scheduled resource and may identify, from the control element of the transmission, an indication to continue monitoring for one or more additional transmissions over additional TTIs of the set. UE <NUM>-c may continue to monitor for the one or more additional transmissions over the additional TTIs of the set of TTIs after identifying the indication to continue monitoring.

In some aspects, base station <NUM>-c may transmit a second transmission (e.g., a second PDSCH transmission), where the second transmission includes a second control element (e.g., a second MAC-CE <NUM>) and a copy of the data for UE <NUM>-c (e.g., UE data <NUM>).

In some cases, UE <NUM>-c may receive a second transmission (e.g., a PDSCH), where the second transmission includes data for UE <NUM>-c and does not include an indication of a second channel access configuration for accessing the unlicensed spectrum in response to the second transmission. UE <NUM>-c may receive a third transmission after receiving the second transmission, the third transmission including an indication of a second channel access configuration (e.g., via a MAC-CE).

At <NUM>, UE <NUM>-c may transmit a message (e.g., an ACK <NUM>) based on the channel access configuration. UE <NUM>-c may use an uplink channel indicated by the transmission (e.g., by the MAC-CE). The at least one uplink channel may include an uplink control channel, a CG uplink shared channel, a RACH, or a combination thereof. If the at least one uplink channel includes the RACH, UE <NUM>-c may transmit a pre-assigned preamble to base station <NUM>-c based on the at least one uplink channel including the RACH. If the at least one uplink channel includes two or more uplink channels, UE <NUM>-c may select one of them for transmitting the message. Alternatively, UE <NUM>-c may use multiple of the two or more uplink channels to transmit duplicates of the message. In some cases, transmitting the message occurs before an end of the indicated COT (e.g., at <NUM>). UE <NUM>-c may transmit the message before the end of the indicated COT based on the one-shot channel access configuration being indicated by the channel access configuration.

<FIG> shows a block diagram <NUM> of a device <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a UE <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communication manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The receiver <NUM> may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to indication of listen-before-talk configuration for uplink communications, etc.). Information may be passed on to other components of the device <NUM>. The receiver <NUM> may be an example of aspects of the transceiver <NUM> described with reference to <FIG>. The receiver <NUM> may utilize a single antenna or a set of antennas.

The communication manager <NUM> may monitor for a transmission over a set of periodically scheduled resources of a downlink shared channel in an unlicensed spectrum, receive the transmission, where the transmission indicates a channel access configuration for the UE for accessing the unlicensed spectrum, and transmit a message based on the channel access configuration. The communication manager <NUM> may be an example of aspects of the communication manager <NUM> described herein.

In some examples, the communication manager <NUM> receiving the transmission over a set of periodically scheduled resources may have one or more advantages. For instance, receiving the transmission at pre-configured periodic instances may enable the communication manager <NUM> to have a larger coding gain as compared to having separate transmissions for performing scheduling. The transmission may have more bits than either a data transmission or a control transmission scheduling the data transmission alone and may thus be able to be encoded to achieve a higher coding gain. Additionally, by receiving an indication of channel access configuration in the transmission, the communication manager <NUM> may decrease overhead associated with communicating in the unlicensed spectrum.

The communication manager <NUM>, or its sub-components, may be implemented in hardware, code (e.g., software or firmware) executed by a processor, or any combination thereof. If implemented in code executed by a processor, the functions of the communication manager <NUM>, or its sub-components may be executed by a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure.

The communication manager <NUM>, or its sub-components, may be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations by one or more physical components. In some aspects, the communication manager <NUM>, or its sub-components, may be a separate and distinct component in accordance with various aspects of the present disclosure. In some aspects, the communication manager <NUM>, or its sub-components, may be combined with one or more other hardware components, including but not limited to an input/output (I/O) component, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof in accordance with various aspects of the present disclosure.

In some aspects, the transmitter <NUM> may be collocated with a receiver <NUM> in a transceiver module.

<FIG> shows a block diagram <NUM> of a device <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a device <NUM>, or a UE <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communication manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The communication manager <NUM> may be an example of aspects of the communication manager <NUM> as described herein. The communication manager <NUM> may include a transmission monitoring component <NUM>, a transmission receiver <NUM>, and a message transmitter <NUM>. The communication manager <NUM> may be an example of aspects of the communication manager <NUM> described herein.

The transmission monitoring component <NUM> may monitor for a transmission over a set of periodically scheduled resources of a downlink shared channel in an unlicensed spectrum.

The transmission receiver <NUM> may receive the transmission, where the transmission indicates a channel access configuration for the UE for accessing the unlicensed spectrum.

The message transmitter <NUM> may transmit a message based on the channel access configuration.

In some examples, the transmission receiver <NUM> receiving the transmission over a set of periodically scheduled resources may have one or more advantages. For instance, receiving the transmission at pre-configured periodic instances may enable the transmission receiver <NUM> to have a larger coding gain as compared to having separate transmissions for performing scheduling. The transmission may have more bits than either a data transmission or a control transmission scheduling the data transmission alone and may thus be able to be encoded to achieve a higher coding gain. Additionally, by receiving an indication of channel access configuration in the transmission, the transmission receiver <NUM> may decrease overhead associated with communicating in the unlicensed spectrum.

<FIG> shows a block diagram <NUM> of a communication manager <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The communication manager <NUM> may be an example of aspects of a communication manager <NUM>, a communication manager <NUM>, or a communication manager <NUM> described herein. The communication manager <NUM> may include a transmission monitoring component <NUM>, a transmission receiver <NUM>, a message transmitter <NUM>, an uplink channel selection component <NUM>, a channel access procedure component <NUM>, and a request transmitter <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

The transmission monitoring component <NUM> may monitor for a transmission over a set of periodically scheduled resources of a downlink shared channel in an unlicensed spectrum. In some aspects, the transmission monitoring component <NUM> may identify, from the control element, an indication to continue monitoring for one or more additional transmissions over additional TTIs of the set of TTIs. In some aspects, the transmission monitoring component <NUM> may continue to monitor for the one or more additional transmissions over the additional TTIs of the set of TTIs after identifying the indication to continue the monitoring.

The transmission receiver <NUM> may receive the transmission, where the transmission indicates a channel access configuration for the UE for accessing the unlicensed spectrum. In some aspects, the transmission receiver <NUM> may transmit a pre-assigned preamble to a base station based on the at least one uplink channel including the random access channel. In some aspects, receiving a second transmission, where the second transmission includes a second control element and a copy of the data for the UE. In some aspects, the transmission receiver <NUM> may receive the second transmission from the base station during the COT. In some aspects, the transmission receiver <NUM> may receive a third transmission from a second base station during the COT. In some aspects, the transmission receiver <NUM> may receive the transmission over a first TTI of a set of TTIs of a periodically scheduled resource. In some aspects, receiving a second transmission, where the second transmission includes a second control element that indicates a downlink feedback indication (DFI). In some aspects, receiving a second transmission, where the second transmission includes data for the UE and does not include an indication of a second channel access configuration for accessing the unlicensed spectrum in response to the second transmission. In some aspects, receiving a third transmission after receiving the second transmission, where the third transmission includes the indication of the second channel access configuration. In some cases, the transmission includes a control element that indicates the channel access configuration. In some cases, the at least one uplink channel includes an uplink control channel, a configured-grant uplink shared channel, a random access channel, or a combination thereof. In some cases, the transmission further includes data for the UE. In some cases, the second transmission includes a second control element. In some cases, the second transmission further includes data for the UE. In some cases, the control element includes an indication of downlink shared channel transmission to message timing, an uplink control channel resource indicator, a configured-grant uplink shared channel indicator, a preamble index for a random access channel, an indication of an end of a channel occupancy time (COT), or a combination thereof.

The message transmitter <NUM> may transmit a message based on the channel access configuration. In some aspects, the message transmitter <NUM> may transmit an acknowledgement message for the second transmission based on the indicated second channel access configuration. In some aspects, the message transmitter <NUM> may suppress transmission of the acknowledgement message prior to receiving the third transmission based on a channel access capability of the UE. In some cases, the message includes an acknowledgement message associated with the transmission.

The uplink channel selection component <NUM> may select one uplink channel of the two or more uplink channels for transmitting the acknowledgement message. In some aspects, the uplink channel selection component <NUM> may transmit copies of the acknowledgement message over at least two of the two or more uplink channels.

The channel access procedure component <NUM> may perform a channel access procedure on the unlicensed spectrum. In some aspects, the channel access procedure component <NUM> may identify a channel occupancy time (COT) associated with a successful acquisition of the unlicensed spectrum for performing communications based on the channel access procedure. In some cases, the channel access procedure includes a listen-before-talk procedure with random back off for acquiring a configured-grant uplink channel.

The request transmitter <NUM> may transmit a request for a second transmission to a base station.

<FIG> shows a diagram of a system <NUM> including a device <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The device <NUM> may be an example of or include the components of device <NUM>, device <NUM>, or a UE <NUM> as described herein. The device <NUM> may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communication manager <NUM>, a transceiver <NUM>, an antenna <NUM>, memory <NUM>, and a processor <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>).

The communication manager <NUM> may monitor for a transmission over a set of periodically scheduled resources of a downlink shared channel in an unlicensed spectrum, receive the transmission, where the transmission indicates a channel access configuration for the UE for accessing the unlicensed spectrum, and transmit a message based on the channel access configuration.

The processor <NUM> may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor <NUM> may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into the processor <NUM>. The processor <NUM> may be configured to execute computer-readable instructions stored in a memory (e.g., the memory <NUM>) to cause the device <NUM> to perform various functions (e.g., functions or tasks supporting indication of listen-before-talk configuration for uplink communications).

<FIG> shows a block diagram <NUM> of a device <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a base station <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communication manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The communication manager <NUM> may transmit, to a UE, a transmission over at least one of a set of periodically scheduled resources for the UE of a downlink shared channel in an unlicensed spectrum, where the transmission indicates a channel access configuration for the UE for the unlicensed spectrum and receive a message based on the indicated channel access configuration. The communication manager <NUM> may be an example of aspects of the communication manager <NUM> described herein.

In some examples, the communication manager <NUM> transmitting the transmission over a set of periodically scheduled resources may have one or more advantages. For instance, transmitting the transmission at pre-configured periodic instances may enable the communication manager <NUM> to have a larger coding gain as compared to having separate transmissions for performing scheduling. The transmission may have more bits than either a data transmission or a control transmission scheduling the data transmission alone and may thus be able to be encoded to achieve a higher coding gain. Additionally, the communication manager <NUM> when communicating with a UE <NUM> may be able to use advanced downlink CoMP for better performance since the transmission is arranged at pre-configured instants. Additionally, by transmitting an indication of channel access configuration in the transmission, the communication manager <NUM> may decrease overhead associated with communicating in the unlicensed spectrum.

The communication manager <NUM>, or its sub-components, may be implemented in hardware, code (e.g., software or firmware) executed by a processor, or any combination thereof. If implemented in code executed by a processor, the functions of the communication manager <NUM>, or its sub-components may be executed by a general-purpose processor, a DSP, an application-specific integrated circuit (ASIC), a FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure.

<FIG> shows a block diagram <NUM> of a device <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a device <NUM>, or a base station <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communication manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The communication manager <NUM> may be an example of aspects of the communication manager <NUM> as described herein. The communication manager <NUM> may include a transmission transmitter <NUM> and a message receiver <NUM>. The communication manager <NUM> may be an example of aspects of the communication manager <NUM> described herein.

The transmission transmitter <NUM> may transmit, to a UE, a transmission over at least one of a set of periodically scheduled resources for the UE of a downlink shared channel in an unlicensed spectrum, where the transmission indicates a channel access configuration for the UE for the unlicensed spectrum.

The message receiver <NUM> may receive a message based on the indicated channel access configuration.

In some examples, the transmission transmitter <NUM> transmitting the transmission over a set of periodically scheduled resources may have one or more advantages. For instance, transmitting the transmission at pre-configured periodic instances may enable the transmission transmitter <NUM> to have a larger coding gain as compared to having separate transmissions for performing scheduling. The transmission may have more bits than either a data transmission or a control transmission scheduling the data transmission alone and may thus be able to be encoded to achieve a higher coding gain. Additionally, the transmission transmitter <NUM> when communicating with a UE <NUM> may be able to use advanced downlink CoMP for better performance since the transmission is arranged at pre-configured instants. Additionally, by transmitting an indication of channel access configuration in the transmission, the transmission transmitter <NUM> may decrease overhead associated with communicating in the unlicensed spectrum.

<FIG> shows a block diagram <NUM> of a communication manager <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The communication manager <NUM> may be an example of aspects of a communication manager <NUM>, a communication manager <NUM>, or a communication manager <NUM> described herein. The communication manager <NUM> may include a transmission transmitter <NUM>, a message receiver <NUM>, and a request receiver <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

The transmission transmitter <NUM> may transmit, to a UE, a transmission over at least one of a set of periodically scheduled resources for the UE of a downlink shared channel in an unlicensed spectrum, where the transmission indicates a channel access configuration for the UE for the unlicensed spectrum. In some aspects, the transmission transmitter <NUM> may transmit the second transmission during a channel occupancy time (COT) associated with a successful acquisition of the unlicensed spectrum by the UE for performing communications based on a channel access procedure. In some aspects, transmit the transmission over a first TTI of a set of TTIs of a periodically scheduled resource of the set of periodically scheduled resources, where the control element includes an indication to continue monitoring for one or more additional transmissions over additional TTIs of the set of TTIs. In some aspects, the transmission transmitter <NUM> may transmit the one or more additional transmissions over one or more of the additional TTIs of the set of TTIs.

In some aspects, transmit a second transmission, where the second transmission includes a second control element that indicates a downlink feedback indication (DFI). In some aspects, transmit a second transmission, where the second transmission includes a second control element and a copy of the data for the UE. In some aspects, transmit a second transmission, where the second transmission includes data for the UE and does not include an indication of a second channel access configuration for accessing the unlicensed spectrum in response to the second transmission. In some aspects, transmit a third transmission after receiving the second transmission, where the third transmission includes the indication of the second channel access configuration. In some cases, the transmission includes a control element that indicates the channel access configuration. In some cases, the at least one uplink channel includes an uplink control channel, a configured-grant uplink shared channel, a random access channel, or a combination thereof. In some cases, the second transmission includes a second control element. In some cases, the channel access procedure includes a listen-before-talk procedure with random back off for acquiring a configured-grant uplink channel. In some cases, the second transmission further includes data for the UE. In some cases, the control element includes an indication of downlink shared channel transmission to message timing, an uplink control channel resource indicator, a configured-grant uplink shared channel indicator, a preamble index for a random access channel, an indication of an end of a channel occupancy time (COT), or a combination thereof. In some cases, the transmission further includes data for the UE.

The message receiver <NUM> may receive a message based on the indicated channel access configuration. In some aspects, the message receiver <NUM> may receive a pre-assigned preamble from the UE based on the at least one uplink channel including the random access channel. In some aspects, the message receiver <NUM> may receive copies of the acknowledgement message over at least two of the two or more uplink channels. In some aspects, the message receiver <NUM> may receive an acknowledgement message for the second transmission based on the indicated second channel access configuration. In some cases, the message includes an acknowledgement message. In some cases, the at least one uplink channel includes two or more uplink channels, and where the base station receives the acknowledgement message over one of the two or more uplink channels.

The request receiver <NUM> may receive, from the UE, a request for a second transmission.

<FIG> shows a diagram of a system <NUM> including a device <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The device <NUM> may be an example of or include the components of device <NUM>, device <NUM>, or a base station <NUM> as described herein. The device <NUM> may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communication manager <NUM>, a network communications manager <NUM>, a transceiver <NUM>, an antenna <NUM>, memory <NUM>, a processor <NUM>, and an inter-station communications manager <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>).

The communication manager <NUM> may transmit, to a UE, a transmission over at least one of a set of periodically scheduled resources for the UE of a downlink shared channel in an unlicensed spectrum, where the transmission indicates a channel access configuration for the UE for the unlicensed spectrum and receive a message based on the indicated channel access configuration.

The memory <NUM> may include RAM and ROM.

In some aspects, the inter-station communications manager <NUM> may provide an X2 interface within an LTE/LTE-A wireless communication network technology to provide communication between base stations <NUM>.

<FIG> shows a flowchart illustrating a method <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The operations of method <NUM> may be implemented by a UE <NUM> or its components as described herein. For example, the operations of method <NUM> may be performed by a communication manager as described with reference to <FIG>. In some aspects, a UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally or alternatively, a UE may perform aspects of the described functions using special-purpose hardware.

At <NUM>, the UE may monitor for a transmission over a set of periodically scheduled resources of a downlink shared channel in an unlicensed spectrum. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a transmission monitoring component as described with reference to <FIG>.

At <NUM>, the UE may receive the transmission, where the transmission indicates a channel access configuration for the UE for accessing the unlicensed spectrum. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a transmission receiver as described with reference to <FIG>.

At <NUM>, the UE may transmit a message based on the channel access configuration. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a message transmitter as described with reference to <FIG>.

At <NUM>, the UE may perform a channel access procedure on the unlicensed spectrum. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a channel access procedure component as described with reference to <FIG>.

At <NUM>, the UE may identify a COT associated with a successful acquisition of the unlicensed spectrum for performing communications based on the channel access procedure. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a channel access procedure component as described with reference to <FIG>.

At <NUM>, the UE may transmit a request for a second transmission to a base station. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a request transmitter as described with reference to <FIG>.

At <NUM>, the UE may receive the second transmission from the base station during the COT. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a transmission receiver as described with reference to <FIG>.

At <NUM>, the UE may receive the transmission over a first TTI of a set of TTIs of a periodically scheduled resource. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a transmission receiver as described with reference to <FIG>.

At <NUM>, the UE may identify, from the control element, an indication to continue monitoring for one or more additional transmissions over additional TTIs of the set of TTIs. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a transmission monitoring component as described with reference to <FIG>.

At <NUM>, the UE may continue to monitor for the one or more additional transmissions over the additional TTIs of the set of TTIs after identifying the indication to continue the monitoring. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a transmission monitoring component as described with reference to <FIG>.

At <NUM>, the UE may receive a second transmission, where the second transmission includes data for the UE and does not include an indication of a second channel access configuration for accessing the unlicensed spectrum in response to the second transmission. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a transmission receiver as described with reference to <FIG>.

At <NUM>, the UE may receive a third transmission after receiving the second transmission, where the third transmission includes the indication of the second channel access configuration. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a transmission receiver as described with reference to <FIG>.

At <NUM>, the UE may transmit an acknowledgement message for the second transmission based on the indicated second channel access configuration. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a message transmitter as described with reference to <FIG>.

<FIG> shows a flowchart illustrating a method <NUM> that supports indication of listen-before-talk configuration for uplink communications in accordance with aspects of the present disclosure. The operations of method <NUM> may be implemented by a base station <NUM> or its components as described herein. For example, the operations of method <NUM> may be performed by a communication manager as described with reference to <FIG>. In some aspects, a base station may execute a set of instructions to control the functional elements of the base station to perform the described functions. Additionally or alternatively, a base station may perform aspects of the described functions using special-purpose hardware.

At <NUM>, the base station may transmit, to a UE, a transmission over at least one of a set of periodically scheduled resources for the UE of a downlink shared channel in an unlicensed spectrum, where the transmission indicates a channel access configuration for the UE for the unlicensed spectrum. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a transmission transmitter as described with reference to <FIG>.

At <NUM>, the base station may receive a message based on the indicated channel access configuration. The operations of <NUM> may be performed according to the methods described herein. In some aspects, aspects of the operations of <NUM> may be performed by a message receiver as described with reference to <FIG>.

By way of example, and not limitation, non-transitory computer-readable media may include random-access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor.

Claim 1:
A method for wireless communication implemented by a user equipment, UE, (<NUM>) comprising:
monitoring (<NUM>) for a transmission over a set of periodically scheduled resources of a downlink shared channel in an unlicensed spectrum without receiving a corresponding dynamic scheduling grant;
receiving (<NUM>) the transmission, wherein the transmission indicates a listen-before-talk, LBT, configuration for the UE (<NUM>) for accessing the unlicensed spectrum; and
transmitting (<NUM>) a message based at least in part on the LBT configuration.