Abstract: Aligned listen before talk (LBT) gaps for single operator frame-based equipment (FBE) mode new radio (NR) shared spectrum (NR-SS) is disclosed. Within the FBE mode network, the base station determines a plurality of potential transmission bursts within a fixed frame period. The base station may then reserve a plurality of LBT gaps prior to the starting position of each such transmission burst. The base station communicates the location of each of the LBT gaps to all neighboring network entities and contends for access to the fixed frame period at the beginning of the frame regardless of whether it has data for transmission during the frame. Each neighboring base station that receives the LBT gaps locations will use the same locations in order to align the LBT gaps over the FBE mode network.

Abstract: New radio (NR) transmission opportunity (TxOP) structure having flexible starting points are disclosed for wireless communications. When a typical listen before talk (LBT) procedure is performed, the transmitting node will not know ahead of time when the LBT will pass and, thus, when data transmissions can start. NR systems may include a mini-slot design for accommodating transmission units smaller than a slot. Aspects of the present disclosure provide for flexibly increasing the number of potential starting transmission boundaries depending on when the LBT pass is detected. Alternative aspects of the present disclosure determine the potential starting transmission points using a mini-slot based design, a floating slot based design, or a punctured slot based design with a code block group (CBG) level retransmission mechanism.

Abstract: Aspects directed towards a frame-based equipment (FBE) design for a multi-operator New Radio shared spectrum (NR-SS) are disclosed. In one example, at least one contention slot is monitored within a fixed frame period of an unlicensed spectrum, and a determination is performed of whether a channel reservation signal associated with a higher priority node has been detected within the at least one contention slot. For this example, the at least one contention slot is associated with a resource of a subsequent fixed frame period of the unlicensed spectrum. A determination is then made of whether to transmit communication via the resource. Here, the communication is transmitted via the resource, if the channel reservation signal is not detected, and the communication is not transmitted via the resource, if the channel reservation signal is detected.

Abstract: A discovery measurement timing configuration (DMTC) window reservation signal is disclosed for new radio (NR) shared spectrum (NR-SS) networks. The DMTC window is defined providing a reserved location for transmission of essential control signaling and potentially high priority traffic that may be transmitted in a prioritized manner. Access within the DMTC window may be provided with a clear channel assessment (CCA) exempt transmission (CET) option or a non-CET option. When the CET option is used, the reservation duration and period may be conveyed through the channel reservation signal. User equipments (UEs) that detect the reservation signal may re-transmit with added offset to inform neighboring base station that may not be within range of the serving base station. Base station that receive either the transmitted or re-transmitted reservation signal will refrain from communications that may interfere with the reception at the UEs.

Abstract: Subband based uplink access for new radio (NR) shared spectrum (NR-SS) is disclosed. A base station performs a listen before talk (LBT) procedure on system allocated subbands of a shared communication channel. The base station determines a first set of candidate subbands that are signaled to a user equipment (UE). The UE performs an LBT procedure on the first set to identify a second set of candidate subbands including the successful LBT subbands of the first set. Aspects of the disclosure provide for managing and refining the subbands for transmissions. A first aspect provides the UE to determine a transmission behavior based on mismatch between the first and second sets. A second aspect provides the first and second sets in handshaking between the base station and UE for refining the eventual transmission set of subbands. A third aspect provides cross-band LBT reporting for further refining subband selection in later slots.

Abstract: In an embodiment, an access point executes a Clear Channel Assessment (CCA) protocol to determine whether to begin transmission within a DRS Measurement Timing Configuration (DMTC) window. The access point transmits, based on a result of the execution, a multi-subframe DRS within the DMTC window, the multi-subframe DRS including a plurality of DRS subframes that each includes a plurality of symbols.

Abstract: Methods, systems, and devices for wireless communication are described. Various autonomous uplink control channel configurations may be used for unscheduled uplink transmissions. For example, a user equipment (UE) may initiate an unscheduled uplink transmission and may identify an autonomous uplink control channel configuration for the uplink transmission. The UE may transmit control information and data during an initial transmission time interval of a transmission opportunity according to the control channel configuration, where the control channel configuration control may include a number of different waveforms and payload configurations. For example, an autonomous uplink control channel configuration may include control information frequency division multiplexed or time division multiplexed with data and transmitted in one or more frequency interlaces.

Abstract: Wireless communications systems and methods related to multiplexing different waveforms in wireless networks are provided. A first wireless communication device identifies a configuration for communicating a first guard interval (GI)-based waveform signal after at least one of a second GI-based waveform signal or a cyclic prefix (CP)-based waveform signal. The first wireless communication device communicates, with a second wireless communication device, the first GI-based waveform signal including a plurality of first symbols, wherein a beginning symbol of the plurality of first symbols include repetitions of a reference signal sequence based on the configuration.

Abstract: Methods, systems, and devices for wireless communication are described. The payload size for uplink transmissions of unscheduled control information may vary and, in some cases, may be dynamically determined. A user equipment (UE) may determine a payload size or may select a payload size from a set of predetermined sizes. A base station may independently determine the same payload size or it may blindly detect the payload size upon receiving the uplink (UL) transmission. Or the base station may indicate the payload size to the UE. Additionally, UL grants issued to the UE may take one of several forms (e.g., different downlink control indicator formats), and characteristics of the grant may indicate information about resources assigned by the grant, including a location of the resources among various transmission opportunities or whether the grant is for multiple subframes.

Abstract: A medium reservation framework is disclosed for coexistence of coordinated and uncoordinated wireless networks in licensed spectrum and shared spectrum. The proposed medium reservation framework organically takes into account operating regimes with different numbers of Tx/Rx antennas per node, provides flexibility in trading off medium contention aggressiveness and power saving, leverages the inherent synchronization nature of NR, and covers both coordinated and uncoordinated operation scenarios. Various aspects of the medium reservation framework may be centered on one or more combinations of some basic building blocks, such as an operation grid, synchronization signals, and reservation messages, such as a reservation request signal (RRQ) and one or more a reservation response signals (RRS).

Abstract: Wireless communications systems and methods related to operating in a network deployed in a downlink (DL) unlicensed band and an uplink (UL) licensed band are provided. A first wireless communication device communicates, with a second wireless communication device, a first downlink communication signal in a downlink unlicensed band of a network. The first wireless communication device communicates, with the second wireless communication device, a second downlink communication signal in an uplink licensed band of the network. The second downlink communication signal includes at least one of a synchronization signal block (SSB), system information, a random access response, a contention resolution message, paging information, a downlink feedback signal, or low-latency data.

Abstract: Aligned listen before talk (LBT) gaps for single operator frame-based equipment (FBE) mode new radio (NR) shared spectrum (NR-SS) is disclosed. Within the FBE mode network, the base station determines a plurality of potential transmission bursts within a fixed frame period. The base station may then reserve a plurality of LBT gaps prior to the starting position of each such transmission burst. The base station communicates the location of each of the LBT gaps to all neighboring network entities and contends for access to the fixed frame period at the beginning of the frame regardless of whether it has data for transmission during the frame. Each neighboring base station that receives the LBT gaps locations will use the same locations in order to align the LBT gaps over the FBE mode network.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may determine that a serving base station of the UE has obtained access to a wireless channel of a shared radio frequency spectrum band during a transmission opportunity that is separate from a scheduled uplink transmission by the UE. The UE may perform, based at least in part on the determination, a clear channel assessment (CCA) procedure on the wireless channel during a designated quiet portion of the transmission opportunity. The UE may transmit an unsolicited CCA status report to the serving base station during the transmission opportunity based at least in part on the CCA procedure.

Abstract: Techniques providing opportunistic frequency switching for frame based equipment (FBE), such as may be configured to minimize opportunistic frequency switching delay in FBE new radio (NR) unlicensed (NR-U) networks and/or to provide frequency diversity FBE access based on offset sequences of medium sensing occasions for the carrier frequencies are disclosed. Within the FBE mode network, a base station may configure a pattern of sensing locations in each frame for each frequency transmission unit of the plurality of frequency transmission units, wherein an inter-unit delay of sensing locations between a first frequency transmission unit and a next adjacent frequency transmission unit and between a last frequency transmission unit and the first frequency transmission unit is a fixed duration.

Abstract: Coordination of listen before talk (LBT) structure in new radio (NR) unlicensed (NR-U) multi-channel access operations is disclosed. In one aspect, when a base station determines to access shared communication spectrum, it may transmit an LBT structure signal that identifies the current LBT structure. The base station would then attempt access to the shared spectrum according to the LBT structure. In another aspect, a coordination server is used to manage access to the shared spectrum. Each node desiring access registers with the coordination server, which provides access parameters for the accessing node to use that increases the likelihood of successful access. The accessing nodes will transmit the selected access configuration used to access the shared spectrum, wherein the access configuration is selected based on the access parameters.

Abstract: Methods, systems, and devices for wireless communications are described. In systems supporting unlicensed downlink and licensed uplink communications, transmitter-based and/or receiver-based listen-before-talk may be implemented. In a transmitter-based scheme, a base station performs listen-before-talk on a downlink unlicensed band to monitor for signals from other base stations. In a first receiver-based scheme, a user equipment may send a clear to send signal on the licensed uplink channel or unlicensed downlink channel to assist a listen-before-talk operation at a serving base station. In a second receiver-based scheme, the user equipment monitors for downlink preamble transmissions from base stations other than a serving base station and reports detected preambles to the serving base station. The base station may schedule the user equipment based on the reported preambles.

Abstract: Methods, systems, and devices for wireless communications are described. A base station of a first network operator (OP) may determine a priority for the first OP for a transmission opportunity of a shared or unlicensed channel. The priority may be lower than a priority of a second OP for the transmission opportunity. Base station may transmit a tentative grant to a user equipment (UE) of the first OP scheduling transmissions over resources of the transmission opportunity. The transmitting device of the first OP may monitor a contention window for reservation signals communicated by devices of the second OP. Based on the monitoring and the tentative grant, the transmitting device of the first OP may perform the transmission over the resources of the shared or unlicensed channel.

Abstract: A discovery measurement timing configuration (DMTC) window reservation signal is disclosed for new radio (NR) shared spectrum (NR-SS) networks. The DMTC window is defined providing a reserved location for transmission of essential control signaling and potentially high priority traffic that may be transmitted in a prioritized manner. Access within the DMTC window may be provided with a clear channel assessment (CCA) exempt transmission (CET) option or a non-CET option. When the CET option is used, the reservation duration and period may be conveyed through the channel reservation signal. User equipments (UEs) that detect the reservation signal may re-transmit with added offset to inform neighboring base station that may not be within range of the serving base station. Base station that receive either the transmitted or re-transmitted reservation signal will refrain from communications that may interfere with the reception at the UEs.

Abstract: Various aspects related to ACK/NACK feedback for multi-TRP transmission scenarios are described. A base station, may send, to a UE, information indicating PDCCH monitoring occasions for each of a plurality of TRPs. In one aspect, the base station may send information indicating whether ACK/NACK feedback across the plurality of TRPs is allowed. The base station may send rules to the UE for performing ACK/NACK feedback bundling for providing feedback to the plurality of TRPs. The base station may also send information indicating a DAI definition for interpreting DAIs transmitted by the plurality of TRPs in corresponding PDCCH transmissions indicating whether the DAIs are independent or joint. The base station may receive a joint ACK/NACK feedback from the UE in a PUCCH based on the rules, or may receive multiple ACK/NACK feedback from the UE in a PUCCH for a first TRP independent from a second TRP.

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) and a base station may communicate in an unlicensed spectrum (e.g., a shared radio frequency spectrum band). As such, the UE may determine a codebook size for transmitting hybrid access request (HARQ) acknowledgement (ACK) feedback with respect to the unlicensed spectrum. Accordingly, the UE may base the HARQ ACK codebook size on a number of HARQ processes with which the UE has been configured. Additionally or alternatively, the UE may base the HARQ ACK codebook size on a number and/or duration of downlink channel monitoring occasions indicated by the base station. In some cases, the UE may base the HARQ ACK codebook size on a combination of the techniques described herein.