Hybrid automatic repeat request round trip time and acknowledgement/negative acknowledgement repetition in discontinuous reception
View Patent ↗A method is provided for detecting a hybrid automatic repeat request (HARQ) message. The method comprising setting a round trip time (RTT) based on a time delay associated with acknowledgement (ACK)/negative acknowledgement (NACK) repetitions, and receiving a retransmitted HARQ message when the RTT expires. Also provided is a user equipment (UE) comprising a processor configured to set an RTT based on a time delay associated with ACK/NACK repetitions, and receive a retransmitted HARQ message when the RTT expires.
1. A method for detecting a hybrid automatic repeat request (HARQ) message, comprising:
setting a round trip time (RTT) based on a time delay associated with receiving a HARQ message;
transmitting a plurality of repeated acknowledgement (ACK)/negative acknowledgement (NACK) sub-frames in response to receiving the HARQ message;
receiving a request to update the predetermined number of ACK/NACK sub-frames; and
updating the predetermined number of ACK/NACK sub-frames based on radio conditions,
wherein the RTT is set equal to a predefined time in addition to a total time delay associated with transmitting the plurality of repeated ACK/NACK sub-frames,
wherein the plurality of repeated ACK/NACK sub-frames is equal to a predetermined number of ACK/NACK sub-frames to be transmitted in response to each received HARQ message.
2. The method of claim 1 further comprising receiving the HARQ message when the RTT expires.
3. The method of claim 1 further comprising, when the HARQ retransmitted, switching to a sleep mode when the RTT is set and waking up when the RTT is expired to receive the retransmitted HARQ message.
4. The method of claim 3 further comprising waking up during a discontinuous reception (DRX) off-duration when the RTT is expired.
5. The method of claim 1 , wherein the plurality of repeated ACK/NACK sub-frames is a predetermined number equal to one of two, four, or six repeated ACK/NACK sub-frames to be transmitted in response to each received HARQ message.
6. The method of claim 1 , wherein the total time delay comprises the time for transporting the plurality of repeated ACK/NACK sub-frames minus the time associated with transmitting one ACK/NACK sub-frame.
7. The method of claim 6 , wherein the predefined time is equal to eight milliseconds, and wherein the time delay for transporting one ACK/NACK sub-frame is equal to one millisecond.
8. The method of claim 7 , wherein communications are established using frequency-division duplexing (FDD).
9. The method of claim 6 , wherein the predefined time is equal to 4+m milliseconds, wherein m is a pre-determined integer.
10. The method of claim 9 , wherein communications are established using time-division duplexing (TDD).
11. A user equipment (UE) comprising:
a processor configured to:
set a round trip time (RTT) based on a time delay associated with receiving a HARQ message;
transmit a plurality of repeated acknowledgement (ACK)/negative acknowledgement (NACK) sub-frames in response to receiving the HARQ message;
receive a request to update a predetermined number of ACK?NACK sub-frames; and
update the predetermined number of ACK/NACK sub-frames based on radio conditions associated with the UE,
wherein the RTT is set equal to a predefined time in addition to a total time delay associated with transmitting the plurality of repeated ACK/NACK sub-frames,
wherein the plurality of repeated ACK/NACK sub-frames is equal to the predetermined number of ACK/NACK sub-frames, and
wherein the processor is configured to transmit the predetermined number of ACK/NACK sub-frames in response to each HARQ message the processor receives.
12. The UE of claim 11 , wherein the HARQ message is received when the RTT is expired.
13. The UE of claim 11 , wherein when the HARQ message is retransmitted, the retransmitted HARQ message is received after waking from a sleep mode when the RTT expires, and wherein the RTT is set before switching to the sleep mode.
14. The UE of claim 13 , wherein switching to the sleep mode promotes saving battery power.
15. The UE of claim 13 , wherein the retransmitted HARQ message is received when the RTT is expired during a discontinuous reception (DRX) off-duration.
16. The UE of claim 11 , wherein the plurality of repeated ACK/NACK sub-frames is a predetermined number equal to one of two, four, or six repeated ACK/NACK sub-frames that the processor is configured to transmit in response to each received HARQ message.
17. The UE of claim 16 , wherein the total time delay comprises the time for transporting the plurality of repeated ACK/NACK sub-frames minus the time associated with transmitting one ACK/NACK sub-frame.
18. The UE of claim 17 , wherein the predefined time is equal to eight milliseconds, and wherein the time delay for transporting one ACK/NACK sub-frame is equal to one millisecond.
19. The UE of claim 18 , wherein communications are established using frequency-division duplexing (FDD).
20. The UE of claim 17 , wherein the predefined time is equal to 4+m milliseconds, and the value of m is dependent on the configurations.
21. The method of claim 20 , wherein communications are established using time-division duplexing (TDD).