Sidelink physical layer procedures for collision avoidance, HARQ feedback, and CSI acquisition
A wireless communication device is disclosed for setting transmission slot priorities in a broadcast environment. Upon receipt of a broadcast signal from the wireless communication environment, the UE analyzes the received signal to determine time slots in which members of its own group are transmitting. The UE then sets priorities of previously-used time slots to be low for allocation purposes. When the UE needs to transmit a signal, it first performs allocation of time slots within the signal frame. This allocation is performed based on the earlier-set priorities such that time slots identified as being used by other group members will not be used unless necessary.
1. A wireless communication device, comprising:
a memory that stores a group ID of the wireless communication device;
radio front end circuitry configured to receive a first broadcast signal;
one or more processors configured to:
determine, based on the first broadcast signal, time slots previously-used by other devices having a same group ID as the wireless communication device;
set the previously-used time slots to have a lower selection priority;
identify retransmission resources from the first broadcast signal;
set the identified retransmission resources to have a higher selection priority;
allocate time slots for signal transmission based on the previously-used time slots and their respective selection priority, wherein the allocation is further based on a quality of service metric; and
cause the radio front end circuitry to transmit a second signal using the allocated time slots.
2. The wireless communication device of claim 1 , wherein the one or more processors are further configured to:
determine that a second broadcast signal was expected to be received; and
determine that the second broadcast signal was not received.
3. The wireless communication device of claim 2 , wherein the one or more processors are further configured to cause the radio front end circuitry to transmit a NACK signal based on the determinations.
4. The wireless communication device of claim 3 , wherein the NACK signal is transmitted according to a Hybrid Automatic Repeat Request (HARQ) procedure.
5. The wireless communication device of claim 4 , wherein the NACK signal includes a HARQ ID and new data indicator (NDI), and
wherein the HARQ ID and NDI are transmitted in a sidelink control information portion of the NACK signal.
6. The wireless communication device of claim 3 , wherein the NACK signal includes the group ID.
7. The wireless communication device of claim 3 , wherein the NACK signal is transmitted a plurality of times.
8. The wireless communication device of claim 2 , wherein the one or more processors are further configured to cause the radio front end circuitry to transmit an announcement signal to announce a collision based on the determining that the second broadcast signal was not received.
9. The wireless communication device of claim 8 , wherein the announcement signal is transmitted once and is associated with the group ID and a time instance of collision detection.
10. A method of a wireless communication device allocating transmission resources in a wireless communication environment, the method comprising:
storing a group ID associated with the wireless communication device;
receiving a first broadcast signal;
determine, based on the first broadcast signal, time slots previously-used by other devices having a same group ID as the wireless communication device;
set the previously-used time slots to have a lower selection priority;
identify retransmission resources from the first broadcast signal;
set the identified retransmission resources to have a higher selection priority;
allocate time slots for signal transmission based on the previously-used time slots and their respective selective priority, wherein the allocation is further based on a quality of service metric; and
transmit a second signal using the allocated time slots.
11. The method of claim 10 , further comprising:
determining that a second broadcast signal was expected to be received; and
determining that the second broadcast signal was not received.
12. The method of claim 11 , further comprising transmitting a NACK signal based on the determining that the broadcast signal was not received.
13. The method of claim 12 , wherein the NACK signal is transmitted according to a Hybrid Automatic Repeat Request (HARQ) procedure.
14. The method of claim 13 , wherein the NACK signal includes a HARQ ID and new data indicator (NDI), and
wherein the HARQ ID and NDI are transmitted in a sidelink control information portion of the NACK signal.
15. The method of claim 12 , wherein the NACK signal includes the group ID.
16. The method of claim 12 , wherein the NACK signal is transmitted a plurality of times.
17. The method of claim 11 , further comprising transmitting an announcement signal based on the determining that the second broadcast signal was not received.
18. The method of claim 17 , wherein the announcement signal is transmitted once and is associated with the group ID and a time instance of collision detection.