US-12621825-B2 - Compact scheduling requests in sidelink

US12621825B2US 12621825 B2US12621825 B2US 12621825B2US-12621825-B2

Abstract

Methods, systems, and devices for wireless communications are described. A user equipment (UE) to be scheduled by a scheduler UE in a sidelink system may transmit a first scheduling request (SR) to request sidelink resources. The UE may transmit the first SR via a set of feedback resources. The scheduler UE may transmit, to the UE, a sidelink control message to schedule a sidelink transmission. The sidelink control message may indicate a set of feedback resources mapped to the sidelink transmission. The UE may transmit the scheduled sidelink transmission based on the sidelink control message and may request additional sidelink resources. The UE may transmit a second SR, where the second SR is transmitted via the set of feedback resources mapped to the sidelink transmission.

Inventors

Gabi SARKIS
Guangyi Liu
Tien Viet Nguyen
Qing Li
Karthika Paladugu

Assignees

QUALCOMM INCORPORATED

Dates

Publication Date: 20260505
Application Date: 20211207

Claims (20)

1 . A method for wireless communications at a first wireless device, comprising: receiving, from a second wireless device, a sidelink data message comprising data for the first wireless device and a trigger for a scheduling request, and indicating a set of feedback resources associated with the sidelink data message, wherein a timing of the set of feedback resources is based at least in part on a transmission time interval in which the sidelink data message is received; transmitting, to the second wireless device via the set of feedback resources based at least in part on receiving the sidelink data message, the scheduling request for sidelink resources for the first wireless device; and receiving, from the second wireless device, a grant for the sidelink resources in response to the scheduling request.
2 . The method of claim 1 , further comprising: selecting the set of feedback resources from multiple sets of feedback resources of a second transmission time interval that is associated with the transmission time interval.
3 . The method of claim 2 , wherein selecting the set of feedback resources comprises: selecting the set of feedback resources based at least in part on an identifier of the first wireless device or an assignment configuration associated with the multiple sets of feedback resources.
4 . The method of claim 2 , wherein selecting the set of feedback resources comprises: selecting the set of feedback resources based at least in part on a first periodicity associated with the first wireless device, a second periodicity associated with the multiple sets of feedback resources, or both.
5 . The method of claim 1 , further comprising: receiving an indication of the set of feedback resources indicated in the sidelink data message to use for transmission of the scheduling request, wherein the scheduling request is transmitted via the set of feedback resources based at least in part on receiving the indication.
6 . The method of claim 5 , wherein receiving the indication of the set of feedback resources comprises: receiving the indication of the set of feedback resources via a PC5 message, a radio resource control (RRC) message, a medium access control (MAC) control element (MAC-CE), or any combination thereof.
7 . The method of claim 5 , wherein the indication of the set of feedback resources comprises a second indication of a second set of feedback resources in a second transmission time interval subsequent the set of feedback resources, the second set of feedback resources corresponding to a subsequent scheduling request occasion for the first wireless device.
8 . The method of claim 1 , wherein transmitting the scheduling request comprises: transmitting the scheduling request according to a set of transmission parameters associated with the first wireless device, the set of feedback resources, or both.
9 . The method of claim 8 , further comprising: receiving an indication of the set of transmission parameters from the second wireless device via a PC5 message, a radio resource control (RRC) message, a UE assistance framework message, or any combination thereof.
10 . The method of claim 8 , wherein the set of transmission parameters is specific to the first wireless device or a set of wireless devices including the first wireless device.
11 . The method of claim 8 , wherein the set of transmission parameters comprises a destination identifier, a packet delay budget, a priority level, a number of retransmissions, a transport block size, a number of sub-channels, or any combination thereof.
12 . The method of claim 1 , wherein the set of feedback resources is allocated to a set of wireless devices including the first wireless device.
13 . The method of claim 1 , wherein the sidelink data message comprises a second grant for second sidelink resources for the first wireless device.
14 . A first wireless device for wireless communications, comprising: one or more processors; one or more memories coupled with the one or more processors; and instructions stored in the one or more memories and executable by the one or more processors to cause the first wireless device to: receive, from a second wireless device, a sidelink data message comprising data for the first wireless device and a trigger for a scheduling request, and indicating a set of feedback resources associated with the sidelink data message, wherein a timing of the set of feedback resources is based at least in part on a transmission time interval in which the sidelink data message is received; transmit, to the second wireless device via the set of feedback resources based at least in part on receiving the sidelink data message indicating the set of feedback resources, the scheduling request for sidelink resources for the first wireless device; and receive, from the second wireless device, a grant for the sidelink resources in response to the scheduling request.
15 . The first wireless device of claim 14 , wherein the instructions are further executable by the one or more processors to cause the first wireless device to: select the set of feedback resources from multiple sets of feedback resources of a second transmission time interval that is associated with the transmission time interval.
16 . The first wireless device of claim 15 , wherein the instructions are further executable by the one or more processors to cause the first wireless device to: select the set of feedback resources based at least in part on an identifier of the first wireless device or an assignment configuration associated with the multiple sets of feedback resources.
17 . The first wireless device of claim 15 , wherein the instructions are further executable by the one or more processors to cause the first wireless device to: select the set of feedback resources based at least in part on a first periodicity associated with the first wireless device, a second periodicity associated with the multiple sets of feedback resources, or both.
18 . The first wireless device of claim 14 , wherein the instructions are further executable by the one or more processors to cause the first wireless device to: receive an indication of the set of feedback resources indicated in the sidelink data message to use for transmission of the scheduling request, wherein the scheduling request is transmitted via the set of feedback resources based at least in part on receiving the indication.
19 . The first wireless device of claim 18 , wherein the instructions are further executable by the one or more processors to cause the first wireless device to: receive the indication of the set of feedback resources via a PC5 message, a radio resource control (RRC) message, a medium access control (MAC) control element (MAC-CE), or any combination thereof.
20 . The first wireless device of claim 18 , wherein the indication of the set of feedback resources comprises a second indication of a second set of feedback resources in a second transmission time interval subsequent the set of feedback resources, the second set of feedback resources corresponding to a subsequent scheduling request occasion for the first wireless device.

Description

FIELD OF TECHNOLOGY The following relates to wireless communications, including compact scheduling requests in sidelink. BACKGROUND Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may be referred to as New Radio (NR) systems. These systems may employ technologies such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A wireless multiple-access communications system may include one or more base stations or one or more network access nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE). SUMMARY Generally, the described techniques relate to procedures for compact scheduling requests (SRs) in sidelink systems. The procedures enable a user equipment (UE) to transmit an SR using feedback resources such as those that would have otherwise gone unused based on current techniques. For instance, a UE to be scheduled by a scheduler UE in a sidelink system may transmit a first SR to request sidelink resources. The UE may transmit the first SR via a set of feedback resources, such as feedback resources associated with a previous transmission. The scheduler UE may transmit, to the UE, a sidelink control message to schedule a sidelink transmission in response to the first SR. In some examples, the sidelink control message may indicate a set of feedback resources associated with (mapped to) the sidelink control message or the sidelink transmission scheduled by the sidelink control message. The UE may receive the sidelink control message and may transmit the scheduled sidelink transmission based on the sidelink control message. In some cases, the UE may request additional sidelink resources for sidelink communications. In these cases, the UE may transmit a second SR to the scheduler UE via the set of feedback resources associated with the sidelink control message or the sidelink transmission. A method for wireless communications at a first wireless device is described. The method may include receiving a sidelink message from a second wireless device, the sidelink message indicating a set of feedback resources associated with the sidelink message, where a timing of the set of feedback resources is based on a transmission time interval (TTI) in which the sidelink message is received, transmitting, to the second wireless device via the set of feedback resources, an SR for sidelink resources for the first wireless device, and receiving, from the second wireless device, a grant for the sidelink resources in response to the SR. An apparatus for wireless communications at a first wireless device is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive a sidelink message from a second wireless device, the sidelink message indicating a set of feedback resources associated with the sidelink message, where a timing of the set of feedback resources is based on a TTI in which the sidelink message is received, transmit, to the second wireless device via the set of feedback resources, a SR for sidelink resources for the first wireless device, and receive, from the second wireless device, a grant for the sidelink resources in response to the SR. Another apparatus for wireless communications at a first wireless device is described. The apparatus may include means for receiving a sidelink message from a second wireless device, the sidelink message indicating a set of feedback resources associated with the sidelink message, where a timing of the set of feedback resources is based on a TTI in which the sidelink message is received, means for transmitting, to the second wireless device via the set of feedback resources, a SR for sidelink resources for the first wireless device, and means for receiving, from the second wireless device, a grant for the sidelink resources in response to the SR. A non-transitory computer-readable medium storing code for wireless communications at a first wireless device is described. The code may include instructions executable by a processor to receive a sidelink message from a second wireless device, the sidelink message indicating a set of feedback resources associated with the sidelink message, where a t