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: User equipment associated with a legacy network may utilize a bottom-to-top search technique to identify relevant control channel samples. Generating a control channel that is configured for the bottom-to-top search technique may lead to poor performance in a single-carrier waveform, which may be disadvantageous as networks move toward New Radio. In some aspects, described herein, a base station generates a control channel that is configured to minimize gaps in the control channel, and a user equipment performs a top-to-bottom search technique to identify relevant control channel samples. By using the top-to-bottom search technique, degradation of single-carrier waveforms is reduced and efficiency is improved.

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.

Abstract: Some techniques and apparatuses described herein may be used to avoid or reduce collisions between uplink data communications and uplink control communications for an enhanced machine-type communication user equipment (eMTC UE) operating in an unlicensed radio frequency spectrum band. Furthermore, some techniques and apparatuses may avoid such collision while still allowing efficient use of resources, such as by deferring the uplink data communication within a data segment, rate matching an uplink data communication around uplink control resources (e.g., cell-specific uplink control resources and/or UE-specific uplink control resources), puncturing the uplink data communication to avoid the uplink control resources, multiplexing uplink control information on an uplink data channel, and/or the like.

Abstract: Methods, systems, and devices for wireless communications are described that asynchronous carrier aggregation, including between high frequency band and lower frequency band transmissions. A user equipment (UE) may be configured to monitor transmissions in a first frequency band and a second frequency band. The UE may measure a timing difference between transmissions in the first frequency band and one or more of the transmissions in the second frequency band, and transmit an indication of the timing difference to a base station. The base station may use the timing difference to determine whether the UE is to use asynchronous carrier aggregation. If the base station determines that the UE is to use asynchronous carrier aggregation, the base station may configure the UE to observe at least a minimum amount of delay when conducting uplink signaling via one of the frequency bands.

Abstract: A method of wireless communication may include determining a communication operation between a base station and one or more served UEs. The method may further include monitoring for radio frequency (RF) energy on a communication channel at a beginning of a listen before talk (LBT) window of a current frame in a shared spectrum shared between at least one or more opportunistic general authorized users. The method may further include transmitting an LBT trigger signal in response to detection of no RF energy above a minimum energy threshold at the beginning of the LBT window. The method may further include receiving an LBT trigger response signal from the one or more served UEs. The method may also include communicating, by the base station, with the one or more UEs during a channel occupancy time (COT) of the current frame after the LBT window.

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: 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.

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: 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: A method, an apparatus, and a computer program for wireless communication that allows for greater scheduling flexibility of physical resources are disclosed. A UE determines a time division duplex (TDD) frame structure for a plurality of frames, where the plurality of frames include a plurality of uplink (UL) subframes and a plurality of downlink (DL) subframes. The UE determines whether a control signaling instance is scheduled during an UL subframe of the plurality of UL subframes, wherein the control signaling instance is scheduled periodically and the control signaling includes at least one of a random access channel, an uplink control channel, a sounding reference signal (SRS), or a scheduling request (SR). The UE communicates the control signaling instance if the control signaling instance is scheduled during an UL subframe.

Abstract: Methods, systems, and devices for wireless communications are described that asynchronous carrier aggregation, including between high frequency band and lower frequency band transmissions. A user equipment (UE) may be configured to monitor transmissions in a first frequency band and a second frequency band. The UE may measure a timing difference between transmissions in the first frequency band and one or more of the transmissions in the second frequency band, and transmit an indication of the timing difference to a base station. The base station may use the timing difference to determine whether the UE is to use asynchronous carrier aggregation. If the base station determines that the UE is to use asynchronous carrier aggregation, the base station may configure the UE to observe at least a minimum amount of delay when conducting uplink signaling via one of the frequency bands.

Abstract: Some techniques and apparatuses described herein may be used to avoid or reduce collisions between uplink data communications and uplink control communications for an enhanced machine-type communication user equipment (eMTC UE) operating in an unlicensed radio frequency spectrum band. Furthermore, some techniques and apparatuses may avoid such collision while still allowing efficient use of resources, such as by deferring the uplink data communication within a data segment, rate matching an uplink data communication around uplink control resources (e.g., cell-specific uplink control resources and/or UE-specific uplink control resources), puncturing the uplink data communication to avoid the uplink control resources, multiplexing uplink control information on an uplink data channel, and/or the like.

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: 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: Various aspects of the disclosure relate to event triggers for independent links. For example, an event trigger may be based on measurements from multiple links. In some aspects, the independent links may involve a first device (e.g., a user equipment) communicating via different independent links with different devices (e.g., transmit receive points (TRPs) or sets of TRPs). For example, the first device may communicate with a second device (e.g., a TRP) via a first link and communicate with a third device (e.g., a TRP) via a second link. In some scenarios, an event trigger may be based on aggregated measurements from multiple links.

Abstract: When a base station is capable of using multiple different types of waveforms for a downlink communication to a UE, the UE may waste processing resources attempting to receive and/or process the downlink communication. For example, the UE may cycle through various possible types of waveforms in an attempt to process the downlink communication. Techniques described herein use waveform signaling for downlink communications to notify the UE of a type of waveform being used for a downlink communication, thereby conserving UE resources (e.g., processing resources, memory resources, RF resources, and/or the like) that would otherwise be wasted attempting to process the downlink communication using multiple types of waveforms.

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: Techniques for autonomous uplink (AUL) transmissions are provided that allow for efficient use of shared radio frequency spectrum band resources. A user equipment (UE) may determine a duration of an AUL transmission and modify an uplink waveform or provide an indication to a base station of one or more channel resources that may be available for base station transmissions, in order to more fully utilize shared radio frequency spectrum band resources within a maximum channel occupancy time (MCOT). A base station may activate or deactivate AUL transmissions through downlink control information (DCI) transmitted to the UE. A UE and base station may exchange various other control information to provide relatively efficient autonomous uplink transmissions and use of the shared radio frequency spectrum band resources.

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.