Sidelink control information stage 2 format
Systems, methods, and circuitries are provided for performing sidelink communication. An example method generates SCI stage 1 and stage 2 for transmitting a transport block (TB) to a user equipment device (UE). The method includes determining the type of sidelink communication for transmitting the TB. An SCI stage 2 format is selected based on the type of sidelink communication. An SCI stage 2 payload is encoded in accordance with the selected SCI stage 2 format. The selected SCI stage 2 format value is encoded in an SCI stage 1 payload. The SCI stage 1 payload and SCI stage 2 payload are transmitted to the UE.
1. A user equipment wireless communication device (UE), comprising a memory and one or more processors configured to, when executing instructions stored in the memory, cause the first UE to:
select a sidelink control information (SCI) stage 2 format based on a sidelink communication type by:
selecting a first SCI stage 2 format when the sidelink communication type is groupcast with acknowledgement/non-acknowledgement (ACK/NACK) feedback enabled, broadcast, or unicast; and
selecting a second SCI stage 2 format when the sidelink communication type is groupcast with NACK feedback only enabled; and
transmit, to a second UE, an SCI stage 2 payload in accordance with the selected SCI stage 2 format.
2. The UE of claim 1 , wherein the one or more processors are configured to cause the UE to, when the first SCI stage 2 format or the second SCI stage 2 format is selected,
enable a feedback bit in the SCI stage 2 payload to instruct the second UE to provide ACK/NACK feedback; or
disable the feedback bit in the SCI stage 2 payload to instruct the second UE not to provide feedback.
3. The UE of claim 1 , wherein the one or more processors are configured to cause the UE to, when the second SCI stage 2 format is selected,
encode a communication range in the SCI stage 2 payload that defines a distance with respect to the first UE;
enable a feedback bit to cause the second UE to provide NACK feedback when the second UE is within the communication range with respect to the first UE and not to provide feedback when the second UE is outside the communication range with respect to the first UE; and
disable the feedback bit to cause the second UE to not provide feedback.
4. The UE of claim 1 , wherein the one or more processors are configured to cause the UE to, when the second SCI stage 2 format is selected,
encode a communication range in the SCI stage 2 payload that defines a distance with respect to the first UE to cause the second UE to provide NACK feedback when the second UE is within the communication range with respect to the first UE and not to provide feedback when the second UE is outside the communication range with respect to the first UE; and
set the communication range to zero to cause the second UE to not provide feedback.
5. A method for a user equipment (UE), comprising:
selecting a first sidelink control information (SCI) stage 2 format when a sidelink communication type is groupcast with acknowledgement/non-acknowledgement (ACK/NACK) feedback enabled, broadcast, or unicast; and
selecting a second SCI stage 2 format when the sidelink communication type is groupcast with NACK feedback only enabled; and
transmitting, to another UE, an SCI stage 2 payload in accordance with the selected SCI stage 2 format.
6. The method of claim 5 , comprising, when the first SCI stage 2 format or the second SCI satge 2 format is selected,
enabling a feedback bit in the SCI stage 2 payload to instruct the other UE to provide ACK/NACK feedback; or
disabling the feedback bit in the SCI stage 2 payload to instruct the other UE not to provide feedback.
7. The method of claim 5 , comprising, when the second SCI stage 2 format is selected,
encoding a communication range in the SCI stage 2 payload that defines a distance with respect to the UE;
enabling a feedback bit to cause the other UE to provide NACK feedback when the other UE is within the communication range and not to provide feedback when the other UE is outside the communication range; and
disabling the feedback bit to cause the other UE to not provide feedback.
8. The method of claim 5 , comprising, when the second SCI stage 2 format is selected,
encoding a communication range in the SCI stage 2 payload that defines a distance with respect to the UE to cause the other UE to provide NACK feedback when the UE is within the communication range and not to provide feedback when the other UE is outside the communication range; and
setting the communication range to zero to cause the other UE to not provide feedback.
9. An apparatus for a first user equipment wireless communication device (UE), comprising a memory and one or more processors configured to, when executing instructions stored in the memory, cause the first UE to
receive a SCI stage 2 from a second UE, wherein
when a sidelink communication type is groupcast with acknowledgement/non-acknowledgement (ACK/NACK) feedback enabled, broadcast, or unicast a first SCI stage 2 format is used; and
when the sidelink communication type is groupcast with NACK feedback only enabled a second SCI stage 2 format is used; and
decode an SCI stage 2 payload in accordance with the SCI stage 2 format.
10. The apparatus of claim 9 , wherein the one or more processors are configured to cause the first UE to, when the first SCI stage 2 format or the second SCI stage 2 format is used,
provide ACK/NACK feedback when a feedback bit in the SCI stage 2 is enabled; or
refrain from providing feedback when the feedback bit in the SCI stage 2 payload is disabled.
11. The apparatus of claim 9 , wherein the one or more processors are configured to cause the first UE to, when the second SCI stage 2 format is used,
decode a communication range in the SCI stage 2 payload that defines a distance with respect to the second UE;
when a feedback bit in the SCI stage 2 format is set, provide NACK feedback when the first UE is within the communication range with respect to the second UE and refrain from providing feedback when the first UE is outside the communication range with respect to the second UE; and
when the feedback bit is disabled, refrain from providing feedback.
12. The apparatus of claim 9 , wherein the one or more processors are configured to cause the first UE to, when the second SCI stage 2 format is selected:
decode a communication range in the SCI stage 2 payload that defines a distance with respect to the second UE;
when a feedback bit in the SCI stage 2 format is set, provide NACK feedback when the first UE is within the communication range with respect to the second UE and refrain from providing feedback when the first UE is outside the communication range with respect to the second UE; and
when the communication range is set to zero refrain from providing feedback.
13. A method for a user equipment (UE), comprising:
receiving sidelink control information (SCI) from another UE, wherein
when a sidelink communication type is groupcast with acknowledgement/non-acknowledgement (ACK/NACK) feedback, broadcast, or unicast a first sidelink control information (SCI) stage 2 format is used and,
when the sidelink communication type is groupcast with NACK feedback only enabled a second SCI stage 2 format is used; and
decoding an SCI stage 2 payload in accordance with the SCI stage 2 format.
14. The method of claim 13 , comprising, when the first SCI stage 2 format or the second SCI stage 2 format is used,
providing ACK/NACK feedback when a feedback bit in the SCI stage 2 payload is enabled; or
refraining from providing feedback when the feedback bit in the SCI stage 2 payload is disabled.
15. The method of claim 13 , comprising, when the second SCI stage 2 format is used,
decoding a communication range in the SCI stage 2 payload that defines a distance with respect to the other UE;
in response to a feedback bit being enabled, providing NACK feedback when the UE is within the communication range and refraining from providing feedback when the UE is outside the communication range; and
in response to the feedback bit being disabled, refraining from providing feedback.
16. The method of claim 13 , comprising, when the second SCI stage 2 format is selected:
decoding a communication range in the SCI stage 2 payload that defines a distance with respect to the other UE;
in response to the UE being within the communication range, providing NACK feedback; and
in response to the UE being outside the communication range, refraining from providing feedback; and
in response to the communication range being set to zero, refraining from providing feedback.