Handling conflicts between dynamic scheduling and random access resource
Methods, systems, and devices for wireless communications are described. In some systems, a user equipment (UE) may perform a random access channel (RACH) procedure with a base station. The UE may receive a message configuring a RACH preamble occasion and an uplink data occasion. The message may be a radio resource control (RRC) message or a system information (SI) message. In some cases, the UE may determine if the RACH preamble occasion, the uplink data occasion, or both are restricted for cancellation based on the message. The UE may determine when to monitor a downlink control channel for dynamic scheduling based on determining which occasions are restricted for cancellation and may transmit a RACH message based on monitoring—or not monitoring—the downlink control channel for dynamic scheduling preempting a RACH occasion. In some other cases, a base station may schedule transmissions to not overlap with configured RACH occasions.
1. An apparatus for wireless communications at a user equipment (UE), comprising:
one or more processors; and
one or more instructions stored in one or more memories and executable by the one or more processors, individually or collectively, to cause the apparatus to:
receive signaling configuring a resource allocation for at least a random access preamble occasion and an uplink data occasion;
receive, via a downlink control channel, a dynamic slot format indicator (SFI),
a cancellation of the random access preamble occasion, the uplink data occasion, or both being based at least in part on the dynamic SFI;
determine if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation based at least in part on receiving the dynamic SFI at a time prior to the random access preamble occasion, the uplink data occasion, or both; and
transmit a random access message in the random access preamble occasion, the uplink data occasion, or both based at least in part on the determining if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation.
2. The apparatus of claim 1 , wherein the one or more instructions executable by the one or more processors to cause the apparatus to determine if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation are executable by the one or more processors to cause the apparatus to:
determine if the random access preamble occasion is restricted for cancellation based at least in part on a first indicator for random access preamble occasion restriction in the signaling.
3. The apparatus of claim 1 , wherein the one or more instructions executable by the one or more processors to cause the apparatus to determine if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation are executable by the one or more processors to cause the apparatus to:
determine if the uplink data occasion is restricted for cancellation based at least in part on a second indicator for uplink data occasion restriction in the signaling.
4. The apparatus of claim 1 , wherein the one or more instructions executable by the one or more processors to cause the apparatus to transmit the random access message are executable by the one or more processors to cause the apparatus to:
transmit, in the random access preamble occasion, a random access preamble message based at least in part on the determining if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation.
5. The apparatus of claim 4 , wherein the one or more instructions are further executable by the one or more processors to cause the apparatus to:
refrain from transmitting, in the uplink data occasion, an uplink data message based at least in part on the determining if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation.
6. The apparatus of claim 1 , wherein:
the signaling comprises system information; and
the signaling configures the resource allocation for contention-based random access.
7. The apparatus of claim 1 , wherein:
the signaling comprises radio resource control signaling; and
the signaling configures the resource allocation for contention-free random access.
8. The apparatus of claim 1 , wherein the one or more instructions executable by the one or more processors to cause the apparatus to transmit the random access message are executable by the one or more processors to cause the apparatus to:
transmit, in the random access preamble occasion, a random access message one (Msg 1) of a four-step random access procedure based at least in part on determining that the random access preamble occasion is restricted for cancellation, wherein the one or more instructions are further executable by the one or more processors to cause the apparatus to:
refrain from monitoring the downlink control channel for dynamic scheduling preempting the random access preamble occasion, the uplink data occasion, or both based at least in part on the random access preamble occasion being restricted for cancellation and the transmitting the random access Msg 1.
9. The apparatus of claim 1 , wherein the one or more instructions are further executable by the one or more processors to cause the apparatus to:
monitor the downlink control channel for dynamic scheduling preempting the uplink data occasion based at least in part on determining that the uplink data occasion is non-restricted for cancellation.
10. The apparatus of claim 1 , wherein the one or more instructions are further executable by the one or more processors to cause the apparatus to:
monitor the downlink control channel for dynamic scheduling preempting the random access preamble occasion, the uplink data occasion, or both based at least in part on determining that the random access preamble occasion is non-restricted for cancellation.
11. The apparatus of claim 1 , wherein the one or more instructions executable by the one or more processors to cause the apparatus to receive the signaling are executable by the one or more processors to cause the apparatus to:
receive a system information message, a radio resource control message, or both configuring a plurality of random access preamble occasions and a plurality of uplink data occasions for a configuration period, the plurality of random access preamble occasions comprising at least the random access preamble occasion and the plurality of uplink data occasions comprising at least the uplink data occasion.
12. A method for wireless communications at a user equipment (UE), comprising:
receiving signaling configuring a resource allocation for at least a random access preamble occasion and an uplink data occasion;
receiving, via a downlink control channel, a dynamic slot format indicator (SFI),
a cancellation of the random access preamble occasion, the uplink data occasion, or both being based at least in part on the dynamic SFI;
determining if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation based at least in part on receiving the dynamic SFI at a time prior to the random access preamble occasion, the uplink data occasion, or both; and
transmitting a random access message in the random access preamble occasion, the uplink data occasion, or both based at least in part on the determining if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation.
13. The method of claim 12 , wherein determining if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation comprises:
determining if the random access preamble occasion is restricted for cancellation based at least in part on a first indicator for random access preamble occasion restriction in the signaling.
14. The method of claim 12 , wherein determining if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation comprises:
determining if the uplink data occasion is restricted for cancellation based at least in part on a second indicator for uplink data occasion restriction in the signaling.
15. The method of claim 12 , wherein transmitting the random access message comprises:
transmitting, in the random access preamble occasion, a random access preamble message based at least in part on the determining if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation.
16. The method of claim 15 , further comprising:
refraining from transmitting, in the uplink data occasion, an uplink data message based at least in part on the determining if the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation.
17. The method of claim 12 , wherein:
the signaling comprises system information; and
the signaling configures the resource allocation for contention-based random access.
18. The apparatus of claim 1 , wherein a processor of the one or more processors comprises a combination of computing devices, a combination of intelligent hardware devices, or both.
19. An apparatus for wireless communications at a network device, comprising:
one or more processors; and
one or more instructions stored in one or more memories and executable by the one or more processors, individually or collectively, to cause the apparatus to:
transmit signaling configuring a resource allocation for at least a random access preamble occasion and an uplink data occasion, the signaling indicating whether the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation;
transmit, via a downlink control channel, a dynamic slot format indicator (SFI) at a time prior to the random access preamble occasion, the uplink data occasion, or both,
a cancellation of the random access preamble occasion, the uplink data occasion, or both being based at least in part on the dynamic SFI; and
receive a random access message in the random access preamble occasion, the uplink data occasion, or both based at least in part on the signaling indicating whether the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation.
20. The apparatus of claim 19 , wherein the signaling comprises a first indicator for random access preamble occasion restriction that indicates whether the random access preamble occasion is restricted for cancellation.
21. The apparatus of claim 19 , wherein the signaling comprises a second indicator for uplink data occasion restriction that indicates whether the uplink data occasion is restricted for cancellation.
22. The apparatus of claim 19 , wherein the one or more instructions executable by the one or more processors to cause the apparatus to receive the random access message are executable by the one or more processors to cause the apparatus to:
receive, in the random access preamble occasion, a random access preamble message based at least in part on the signaling indicating whether the random access preamble occasion, the uplink data occasion, or both are restricted for cancellation.
23. The apparatus of claim 19 , wherein:
the signaling comprises system information; and
the signaling configures the resource allocation for contention-based random access.
24. The apparatus of claim 19 , wherein:
the signaling comprises radio resource control signaling; and
the signaling configures the resource allocation for contention-free random access.
25. The apparatus of claim 19 , wherein the one or more instructions executable by the one or more processors to cause the apparatus to transmit the dynamic SFI are executable by the one or more processors to cause the apparatus to:
transmit, via the downlink control channel, dynamic scheduling preempting the uplink data occasion based at least in part on the signaling indicating that the uplink data occasion is non-restricted for cancellation.
26. The apparatus of claim 19 , wherein the one or more instructions executable by the one or more processors to cause the apparatus to transmit the dynamic SFI are executable by the one or more processors to cause the apparatus to:
transmit, via the downlink control channel, dynamic scheduling preempting the random access preamble occasion, the uplink data occasion, or both based at least in part on the signaling indicating that the random access preamble occasion is non-restricted for cancellation.
27. The apparatus of claim 19 , wherein the one or more instructions executable by the one or more processors to cause the apparatus to transmit the signaling are executable by the one or more processors to cause the apparatus to:
transmit a system information message, a radio resource control message, or both configuring a plurality of random access preamble occasions and a plurality of uplink data occasions for a configuration period, the plurality of random access preamble occasions comprising at least the random access preamble occasion and the plurality of uplink data occasions comprising at least the uplink data occasion.
28. The apparatus of claim 19 , wherein a processor of the one or more processors comprises a combination of computing devices, a combination of intelligent hardware devices, or both.
29. The method of claim 12 , wherein:
the signaling comprises radio resource control signaling; and
the signaling configures the resource allocation for contention-free random access.
30. The method of claim 12 , wherein receiving the signaling comprises:
receiving a system information message, a radio resource control message, or both configuring a plurality of random access preamble occasions and a plurality of uplink data occasions for a configuration period, the plurality of random access preamble occasions comprising at least the random access preamble occasion and the plurality of uplink data occasions comprising at least the uplink data occasion.