Patent Description:
The present disclosure relates generally to communication systems, and more particularly, to a wireless communication system that reselects and/or reserves resources for sidelink communications.

Wireless communication systems, as are for example described in 3GPP R1-<NUM> and <CIT>, are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts.

These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipment (UE) to communicate on a municipal, national, regional, and even global level.

In sidelink communication, a user equipment (UE) may reserve and/or reselect resources for later transmissions. The reservations may identify resources which overlap with resources selected for transmission or reserved by other UEs. A UE may determine when to reserve and/or reselect resources which it had selected but which overlap with a reservation of another UE, or may determine when to preempt a reservation of another UE.

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus determines that at least one resource of a first set of resources selected by the UE for sidelink communication overlaps with a second set of resources reserved by a set of UEs; and determines whether to reselect at least a subset of the first set of resources for a sidelink transmission upon determining that the at least one resource is an overlapping resource, the at least a subset of the first set of resources comprising one of a first overlapping resource of the overlapping resource, the overlapping resource, or the overlapping resource and at least a subset of non-overlapping resources of the first set of resources.

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus determines that at least one resource of a first set of resources selected by the UE for sidelink communication overlaps with a second set of resources reserved by a set of UEs; and determines, upon determining that the at least one resource is an overlapping resource, whether to reserve the at least one resource for a sidelink transmission when at least one of a first priority associated with the at least one resource is the same as a second priority associated with the second set of resources, a remaining time in a packet delay budget (PDB) for a sidelink transmission on the first set resources is greater than a threshold, or the remaining time in the PDB is greater than a remaining time in a PDB associated with the set of UEs for the second set of resources.

In addition to other functions, the base stations <NUM> may perform one or more of the following functions: transfer of user data, radio channel ciphering and deciphering, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), intercell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS), subscriber and equipment trace, RAN information management (RIM), paging, positioning, and delivery of warning messages. The third backhaul links <NUM> may be wired or wireless.

Generally, the AMF <NUM> provides quality of service (QoS) flow and session management.

Some of the UEs <NUM> may be referred to as loT devices (e.g., parking meter, gas pump, toaster, vehicles, heart monitor, etc.).

Referring again to <FIG>, in certain aspects, the UE <NUM> may be configured to determine that at least one resource of a first set of resources selected by the UE for sidelink communication overlaps with a second set of resources reserved by a set of UEs, and the UE <NUM> may also be configured to determine, upon determining that the at least one resource is an overlapping resource, whether to reselect at least a subset of the first set of resources for a sidelink transmission, the at least a subset of the first set of resources comprising one of a first overlapping resource of the overlapping resource, the overlapping resource, or the overlapping resource and at least a subset of non-overlapping resources of the first set of resources, as shown in <NUM>.

<FIG> is a diagram <NUM> illustrating resource allocation in sidelink communication. A UE may select resources for a sidelink transmission. The UE may select resources for a current transmission, or may select the resources to reserve for a future transmission. When a UE transmits a sidelink communication, it may include sidelink control information (SCI). The UE may include a reservation of future resources in the SCI to be transmitted to the other UEs. For example, as illustrated in <FIG>, a UE may select first transmission resources <NUM> for a first transmission, and the first transmission may include SCI which reserves future resources for a second transmission <NUM> and for a third transmission <NUM>. In some aspects, a sidelink transmission may include SCI reserving resources for two future transmissions.

<FIG> is a communication flow diagram <NUM> illustrating a reservation overlap in sidelink communication. As illustrated at <NUM>, A first UE <NUM> may select resources for a sidelink transmission. The first UE <NUM> may select the resources for a transmission which the UE <NUM> is currently preparing to transmit, or may select the resources to identify in a reservation in the SCI of a transmission which the UE <NUM> is currently preparing to transmit.

The UE <NUM> may receive SCI <NUM> from another UE <NUM>, and the SCI <NUM> may include a reservation of future resources. As illustrated at <NUM>, the UE <NUM> may sense for an overlap between the resources selected at <NUM> and resources reserved by other UEs. The reservation of future resources in the SCI <NUM> may identify some or all of the resources selected at <NUM>, which may be referred to as an overlap. In some aspects, the UE <NUM> may have selected the resources for current transmission but may not have transmitted on the resources prior to receiving the overlapping reservation in the SCI <NUM>, or may have selected the resources for future reservation but may not have transmitted the reservation prior to receiving the overlapping reservation in the SCI <NUM>. In some aspects, the UE <NUM> may have already transmitted a reservation for the selected resources, but the reservation received in the SCI <NUM> may be higher priority. Where the UE <NUM> has received SCI attempting to reserve some or all of the resources selected at <NUM>, the UE <NUM> may determine that an overlap has occurred between resources which the UE <NUM> selected for transmission at <NUM> and resources reserved by another UE <NUM>.

As illustrated at <NUM>, upon determining that an overlap has occurred, the UE <NUM> may determine whether to reselect the resources selected at <NUM>.

As illustrated at <NUM>, the UE <NUM> transmits a sidelink transmission <NUM>. (Transmission may be on selected or reselected, based on <NUM>). For example, in some aspects, the UE <NUM> may determine whether the time until the UE <NUM> is to transmit on the selected resources or to transmit SCI reserving the selected resources is greater than a threshold value. If the time is above the threshold, the UE <NUM> may reselect the resources selected at <NUM>, and if the time is not above the threshold, the UE <NUM> may transmit the transmission on the resources selected at <NUM> or may transmit the SCI reserving the resources selected at <NUM>. In some aspects, the UE <NUM> may compare a priority associated with its transmission with a priority of the transmission on the overlapping resources. If the transmission of the UE <NUM> has a higher priority, the UE <NUM> may transmit on the selected resources or may transmit the SCI reserving the selected resource, and if the transmission on the overlapping resources has a higher priority, the UE <NUM> may reselect the resources selected at <NUM>.

The UE <NUM> may transmit a sidelink transmission <NUM> to the other UE <NUM>. Where the UE <NUM> determined to reselect resources at <NUM>, it may transmit the sidelink transmission <NUM> on the reselected resources or may include SCI reserving the reselected resources in the sidelink transmission <NUM>. Where the UE <NUM> determined not to reselect resources at <NUM>, the UE <NUM> may transmit the sidelink transmission <NUM> on the resources selected at <NUM> or may include SCI reserving the resources selected at <NUM> in the sidelink transmission <NUM>.

<FIG> is a diagram <NUM> illustrating sensing for overlapping resources. A UE may be preparing to transmit a first transmission <NUM> at a transmission time <NUM>. The UE may be transmitting the first transmission <NUM> without a reservation, or the UE may be transmitting the first transmission <NUM> on resources reserved by a previous transmission <NUM>. The first transmission <NUM> may include SCI which reserves resources for a second transmission <NUM> and a third transmission <NUM>.

During a sensing period <NUM>, the UE may be sensing for overlap between resources reserved by other UEs and the resources for the first transmission <NUM>, the second transmission <NUM>, and the third transmission <NUM>. The UE may monitor reservations received from other UEs and may determine if the received reservations indicate resources which the UE had selected for the first transmission <NUM>, the second transmission <NUM>, or the third transmission <NUM>. The UE may sense up until a threshold time <NUM> (e.g., a time T3) prior to the transmission time <NUM>.

<FIG> is a diagram <NUM> illustrating a received reservation overlapping with selected resources. A UE may have selected resources for a first transmission <NUM>, a second transmission <NUM>, and a third transmission <NUM>. For example, the first transmission <NUM>, the second transmission <NUM>, and the third transmission <NUM> may be the first transmission <NUM>, the second transmission <NUM>, and the third transmission <NUM> described in connection with <FIG>. The UE may receive a reservation <NUM>, and the received reservation <NUM> may identify overlapping resources <NUM> which overlap with the resources for the first transmission <NUM>. The UE may receive a reservation <NUM>, and the received reservation <NUM> may identify overlapping resources <NUM> which overlap with the resources the UE had reserved or had planned to reserve for the third transmission <NUM>.

If the UE received the received reservation <NUM> or the received reservation <NUM> and detected the overlap ping resources <NUM> or <NUM> during the sensing period <NUM>, the UE may reselect some or all of the resources selected for the first transmission <NUM>, the second transmission <NUM>, or the third transmission <NUM>. In some aspects, the UE may reselect the first overlapping resource in the SCI it is to send. For example, the UE may reselect the resources for the first transmission <NUM>, or just the overlapping resources <NUM>, but may not reselect the resources for the second transmission <NUM> or the resources for the third transmission <NUM> (including the overlapping resources <NUM>). In some aspects, the UE may reselect the overlapping resource, but not reselect the non-overlapping resources. For example, the UE may reselect the overlapping resources <NUM> and <NUM>, but may not reselect the non-overlapping resources of the first transmission <NUM> and the third transmission <NUM>.

In some aspects, the UE may reselect non-overlapping resources in addition to overlapping resources. The UE may reselect non-overlapping resources due to processing timeline issues. For example, a future resource may be overlapping, but the UE may not be able to find new resources and update SCI before the original transmission time. As illustrated in <FIG>, the UE may not be able to find resources to reselect for the third transmission <NUM> prior to transmitting the first transmission <NUM> reserving the resources for the third transmission, so the UE may reselect the resources for the first transmission <NUM>, including the non-overlapping resources. The UE may not be able to find resources to reselect for the first transmission <NUM> prior to the resources selected for the second transmission <NUM>, so the UE may reselect the resources for the first transmission <NUM> and reselect the resources for the second transmission <NUM> to resources after the resources reselected for the first transmission <NUM>. The UE may reselect non-overlapping resources due to signaling restrictions. For example, SCI may only signal reservations that are a set number of slots apart. The UE may reselect the same resources for non-overlapping resources or may choose different resources. In some aspects, the UE behavior with respect to which resources are reselected may be configured or preconfigured per resource pool.

In some aspects, if the UE receives the received reservation <NUM> or the received reservation <NUM> after the sensing period <NUM>, the UE may or may not reselect resources based on the received reservations <NUM> and <NUM>.

In some aspects, the UE may compare a priority of its transmission with that of a received reservation with overlapping resources. For example, the UE may compare a priority of the received reservation <NUM> with a priority of the first transmission <NUM>, or may compare a priority of the received transmission <NUM> with a priority of the third transmission <NUM>. In some aspects, if the received reservation has a higher priority, the UE may reselect the overlapping resources, and if the received reservation has the same or a lower priority, the UE may not reselect the overlapping resources. In some aspects, if the received reservation has the same priority, the UE may reselect the overlapping resources. In some aspects, if the received reservation has the same priority as the transmission of the UE and the UE has not transmitted SCI reserving the resources for its transmission, the UE may reselect the overlapping resources, but if the received reservation has the same priority and the UE already reserved the resources for its transmission, the UE may not reselect the overlapping resources.

In some aspects, the UE may compare a packet delay budget of a transmission with a packet delay budget of a received reservation to determine whether to reselect resources. In some aspects, if the packet delay budget of the UE is greater than the packet delay budget of the received reservation, the UE may reselect the overlapping resources. In some aspects, if the packet delay budget of the transmission of the UE is above a threshold time (e.g., an amount of time for the UE to which it takes the UE to reselect resources), the UE may reselect the overlapping resources.

<FIG> is a communication flow diagram <NUM> illustrating reservation preemption in sidelink communication. <FIG> is a diagram illustrating selected resources overlapping with a previous reservation. A UE <NUM> may receive SCI <NUM> from another UE <NUM> reserving resources for a future transmission of the other UE <NUM>. For example, the SCI <NUM> may be received in a transmission <NUM> from the UE <NUM>, and may include previous reservations <NUM> and <NUM> identifying resources for future transmissions for the UE <NUM>.

As illustrated at <NUM>, the UE <NUM> may select resources for a future transmission of the UE <NUM>. For example, the UE <NUM> may select resources <NUM> for the future transmission. As illustrated at <NUM>, the UE <NUM> may determine that the resources selected at <NUM> overlap with the resources reserved in the SCI <NUM>. For example, the UE <NUM> may determine that selected resources <NUM> and the previous reservation <NUM> both indicate overlapping resources <NUM>.

As illustrated at <NUM>, the UE <NUM> may determine whether to preempt the previous reservation. The UE <NUM> may compare a priority of the transmission of the UE <NUM> (e.g., a priority of the transmission for the selected resources <NUM>) with a priority of the transmission of the UE <NUM> (e.g., a priority of the transmission for the previous reservation <NUM>). The UE <NUM> may then determine whether to preempt the previous reservation based on the comparison of the priority of the transmission of the UE <NUM>. In some aspects, the UE <NUM> may determine to preempt the previous reservation <NUM> if the transmission of the UE <NUM> has a higher priority than the transmission of the UE <NUM>. In some aspects, the UE <NUM> may determine to preempt the previous reservation <NUM> if the transmission of the UE <NUM> has a the same priority as the transmission of the UE <NUM>. In some aspects, the UE <NUM> may compare the packet delay budget of the transmission of the UE <NUM> on the resources of the previous reservation <NUM> with the packet delay budget of the transmission of the UE <NUM> on the selected resources <NUM>. The UE <NUM> may determine to preempt the previous reservation <NUM> if the time remaining in the packet delay budget of the transmission of the UE <NUM> is less than the time remaining in the packet delay budget of the transmission of the UE <NUM>. In some aspects, the UE <NUM> may determine to preempt the previous reservation <NUM> if the time remaining in the packet delay budget of the transmission of the UE <NUM> on the selected resources <NUM> is insufficient to delay transmission without exceeding the packet delay budget.

<FIG> is a flowchart <NUM> of a method of wireless communication. The method may be performed by a UE (e.g., the UE <NUM>, <NUM>, which may include the memory <NUM> and which may be the entire UE or a component of the UE, such as the TX processor <NUM>, the RX processor <NUM>, and/or the controller/processor <NUM>).

At <NUM>, the UE determines that at least one resource of a first set of resources selected by the UE for sidelink communication overlaps with a second set of resources reserved by a set of UEs. The at least one resource may at least partially overlap with the second set of resources. The at least one resource may completely overlap with the second set of resources. For example, in the context of <FIG>, <NUM> may be performed by UE <NUM> selecting at least one resource in a first set of resources as described with respect to <NUM>, and sensing that there is an overlap of the at least one resource with a second set of resources as described with respect to <NUM>.

In some aspects, the UE may receive SCI from the set of UEs, the received SCI indicating the second set of resources. For example, in the context of <FIG>, UE <NUM> may receive SCI as described in <NUM>.

At <NUM>, the UE determines whether to reselect at least a subset of the first set of resources for a sidelink transmission upon determining that the at least one resource is an overlapping resource, the at least a subset of the first set of resources comprising one of a first overlapping resource of the overlapping resource, the overlapping resource, or the overlapping resource and at least a subset of non-overlapping resources of the first set of resources. For example, in the context of <FIG>, <NUM> may be performed by UE <NUM> ascertaining that there is an overlap of the at least one resource in <NUM>, reviewing the resources selected in <NUM>, and reselecting at least a subset of resources in the first set of resources as described with respect to <NUM>.

The UE may determine to reselect the at least the subset of the first set of resources when a remaining time in a packet delay budget for a sidelink transmission on the first set of resources is greater than a threshold.

According to the present invention, the UE has a first transmission priority associated with transmitting in the first set of resources, and the UE determines to reselect the at least the subset of the first set of resources when the overlapping resources are associated with one or more transmission priorities that is the same as the first transmission priority. In an embodiment, the UE has the first transmission priority associated with transmitting in the first set of resources, and the UE determines to reselect the at least the subset of the first set of resources when the overlapping resources are associated with one or more transmission priorities that is the same as the first transmission priority and that the first set of resources are unreserved through transmission of SCI.

At <NUM>, the UE determines, upon determining that the at least one resource is an overlapping resource, whether to reserve the at least one resource for a sidelink transmission when at least one of a first priority associated with the at least one resource is the same as a second priority associated with the second set of resources, a remaining time in a PDB for a sidelink transmission on the first set resources is greater than a threshold, or the remaining time in the PDB is greater than a remaining time in a PDB associated with the set of UEs for the second set of resources. The UE may determine to reserve the at least one resource when the first priority associated with the at least one resource is the same as the second priority associated with the second set of resources. For example, in the context of <FIG>, <NUM> may be performed by UE <NUM> selecting at least one resource in a first set of resources as described with respect to <NUM>, and sensing that there is an overlap of the at least one resource with a second set of resources as described with respect to <NUM>, and reserving the at least one resource for a sidelink transmission as described with respect to <NUM>.

The UE may determine to reserve the at least one resource when the remaining time in the PDB for the sidelink transmission on the first set resources is greater than the threshold. The UE may determine to reserve the at least one resource when the first priority associated with the at least one resource is the same as the second priority associated with the second set of resources and the remaining time in the PDB for the sidelink transmission on the first set resources is greater than the threshold. The UE may determine to reserve the at least one resource when the remaining time in the PDB for the sidelink transmission on the first set resources is greater than the remaining time in the PDB associated with the set of UEs for the second set of resources.

In some aspects, the UE may reselect the at least the subset of the first set of resources for the sidelink transmission upon determining to reselect the at least the subset of the first set of resources. In some aspects, the UE may transmit SCI indicating the at least the subset of the first set of resources that were reselected. In some aspects, the UE may transmit sidelink control information or data to one or more UEs, the sidelink control information or data being transmitted within the at least the subset of the first set of resources that were reselected.

At <NUM>, the UE determines that at least one resource of a first set of resources selected by the UE for sidelink communication overlaps with a second set of resources reserved by a set of UEs. For example, in the context of <FIG>, <NUM> may be performed by UE <NUM> selecting at least one resource in a first set of resources as described with respect to <NUM>, and sensing that there is an overlap of the at least one resource with a second set of resources as described with respect to <NUM>.

At <NUM>, the UE determines, upon determining that the at least one resource is an overlapping resource, whether to reserve the at least one resource for a sidelink transmission when at least one of a first priority associated with the at least one resource is the same as a second priority associated with the second set of resources, a remaining time in a PDB for a sidelink transmission on the first set resources is greater than a threshold, or the remaining time in the PDB is greater than a remaining time in a PDB associated with the set of UEs for the second set of resources. For example, in the context of <FIG>, <NUM> may be performed by UE <NUM> selecting at least one resource in a first set of resources as described with respect to <NUM>, sensing that there is an overlap of the at least one resource with a second set of resources as described with respect to <NUM>, and reserving the at least one resource for a sidelink transmission as described with respect to <NUM>.

The UE may determine to reserve the at least one resource when the first priority associated with the at least one resource is the same as the second priority associated with the second set of resources. The UE may determine to reserve the at least one resource when the remaining time in the PDB for the sidelink transmission on the first set resources is greater than the threshold. The UE may determine to reserve the at least one resource when the first priority associated with the at least one resource is the same as the second priority associated with the second set of resources and the remaining time in the PDB for the sidelink transmission on the first set resources is greater than the threshold. The UE may determine to reserve the at least one resource when the remaining time in the PDB for the sidelink transmission on the first set resources is greater than the remaining time in the PDB associated with the set of UEs for the second set of resources.

The communication manager <NUM> includes a determination component <NUM> that is configured to determine that at least one resource of a first set of resources selected by the UE for sidelink communication overlaps with a second set of resources reserved by a set of UEs, e.g., as described in connection with <NUM> of <FIG> and/or <NUM> of <FIG>.

The communication manager <NUM> further includes a determination component <NUM> that receives input from determination component <NUM> and is configured to determine, upon determination component <NUM> determining that the at least one resource is an overlapping resource, whether to reselect at least a subset of the first set of resources for a sidelink transmission the at least a subset of the first set of resources comprising one of a first overlapping resource of the overlapping resource, the overlapping resource, or the overlapping resource and at least a subset of non-overlapping resources of the first set of resources, e.g., as described in connection with <NUM> of <FIG>.

The apparatus <NUM> may employ reception component <NUM> to receive SCI from the set of UEs, the received SCI indicating the second set of resources as described in connection with <NUM> of <FIG>.

The communication manager <NUM> may further include a selection component <NUM> that reselects the at least the subset of the first set of resources for the sidelink transmission upon determining to reselect the at least the subset of the first set of resources, as described in connection with <NUM> of <FIG>.

The apparatus <NUM> may employ transmission component <NUM> to transmit SCI indicating the at least the subset of the first set of resources that were reselected, as described in connection with <NUM> of <FIG>.

The apparatus <NUM> may employ transmission component <NUM> to transmit sidelink control information or data to one or more UEs, the sidelink control information or data being transmitted within the at least the subset of the first set of resources that were reselected, as described in connection with <NUM> of <FIG>.

The communication manager <NUM> further includes a reservation component <NUM> that receives input from the determination component <NUM> and is configured to reserve, upon determination component <NUM> determining that the at least one resource is an overlapping resource, the at least one resource for a sidelink transmission, when at least one of a first priority associated with the at least one resource is the same as a second priority associated with the second set of resources, a remaining time in a PDB for a sidelink transmission on the first set resources is greater than a threshold, or the remaining time in the PDB is greater than a remaining time in a PDB associated with the set of UEs for the second set of resources, e.g., as described in connection with <NUM> of <FIG> and/or <NUM> of <FIG>.

The apparatus may include additional components that perform each of the blocks of the algorithm in the aforementioned flowcharts of <FIG> and/or <NUM>. As such, each block in the aforementioned flowcharts of <FIG> and/or <NUM> may be performed by a component and the apparatus may include one or more of those components.

In one configuration, the apparatus <NUM>, and in particular the cellular baseband processor <NUM>, includes means for means for determining that at least one resource of a first set of resources selected by the UE for sidelink communication overlaps with a second set of resources reserved by a set of UEs. The apparatus <NUM>, and in particular the cellular baseband processor <NUM>, also includes means for determining, upon determining that the at least one resource is an overlapping resource, whether to reselect at least a subset of the first set of resources for a sidelink transmission the at least a subset of the first set of resources comprising one of a first overlapping resource of the overlapping resource, the overlapping resource, or the overlapping resource and at least a subset of non-overlapping resources of the first set of resources.

The apparatus <NUM>, and in particular the cellular baseband processor <NUM>, may also include means for reserving, upon determining that the at least one resource is an overlapping resource, the at least one resource for a sidelink transmission, when at least one of a first priority associated with the at least one resource is the same as a second priority associated with the second set of resources, a remaining time in a PDB for a sidelink transmission on the first set resources is greater than a threshold, or the remaining time in the PDB is greater than a remaining time in a PDB associated with the set of UEs for the second set of resources.

The aforementioned means may be one or more of the aforementioned components of the apparatus <NUM> configured to perform the functions recited by the aforementioned means. As described supra, the apparatus <NUM> may include the TX Processor <NUM>, the RX Processor <NUM>, and the controller/processor <NUM>.

In sidelink communication, UEs may reserve and/or reselect resources for later transmissions. The reservations may identify resources which overlap with resources selected for transmission or reserved by other UEs. A UE may determine when to reselect and/or reserve resources which it had selected but which overlap with a reservation of another UE, or may determine when to preempt a reservation of another UE.

Claim 1:
A method of wireless communication at a user equipment, UE (<NUM>), comprising:
determining (<NUM>) that at least one resource of a first set of resources selected by the UE (<NUM>) for sidelink communication overlaps with a second set of resources reserved by a set of UEs (<NUM>), wherein the UE has a first transmission priority associated with transmitting in the first set of resources; and
determining (<NUM>), upon determining that the at least one resource is an overlapping resource, to reselect at least a subset of the first set of resources for a sidelink transmission when the overlapping resource is associated with one or more transmission priorities that are same as the first transmission priority, the at least a subset of the first set of resources comprising one of a first overlapping resource of the overlapping resource, the overlapping resource, or the overlapping resource and at least a subset of non-overlapping resources of the first set of resources.