Method and system for supporting multiple hybrid automatic repeat request processes per transmission time interval
A method and apparatus may be used for supporting multiple hybrid automatic repeat request (H-ARQ) processes per transmission time interval (TTI). A transmitter and a receiver may include a plurality of H-ARQ processes. Each H-ARQ process may transmit and receive one TB per TTI. The transmitter may generate a plurality of TBs and assign each TB to a H-ARQ process. The transmitter may send control information for each TB, which may include H-ARQ information associated TBs with the TBs. The transmitter may send the TBs using the associated H-ARQ processes simultaneously per TTI. After receiving the TBs, the receiver may send feedback for each of the H-ARQ processes and associated TBs indicating successful or unsuccessful receipt of each of the TBs to the transmitter. The feedback for multiple TBs may be combined for the simultaneously transmitted H-ARQ processes, (i.e., TBs).
1. A base station for transmitting multiple transport blocks (TB)s, the base station comprising:
a processor configured to generate a plurality of TBs for a wireless transmit/receive unit (WTRU); and
a transmitter configured to:
transmit a control message associated with the plurality of TBs, wherein the control message includes control information for each of the plurality of TBs and includes hybrid automatic repeat request (H-ARQ) information associated with the TBs; wherein the H-ARQ information includes a redundancy version for each of the TBs; and
transmit the plurality of TBs simultaneously in one transmission time interval (TTI).
2. The base station of claim 1 wherein the H-ARQ information includes an H-ARQ process identity (ID) associated with the TBs.
3. The base station of claim 1 wherein the processor is further configured to attach a separate cyclic redundancy check (CRC) to each of the plurality of TBs.
4. The base station of claim 1 further comprising:
a receiver configured to receive combined H-ARQ feedback indicating successful or unsuccessful receipt of each of the plurality of TBs in response to the transmitted TBs.
5. The base station of claim 1 wherein the control information includes an indication of a modulation scheme for each of the TBs.
6. The base station of claim 4 , wherein the processor and transmitter are further configured to implement a synchronous H-ARQ scheme and recognize which feedback corresponds to which H-ARQ process based on a predetermined timing.
7. The base station of claim 1 wherein the control information includes a modulation and coding scheme for each of the TBs.
8. The base station of claim 1 , wherein the transmitter is further configured to transmit the TBs using multiple spatial streams.
9. The base station of claim 1 , wherein the control information includes a transport block size for each of the TBs.
10. A wireless transmit/receive unit (WTRU) for receiving a plurality of transport blocks (TBs), the WTRU comprising:
a receiver configured to:
receive a control message associated with the plurality of TBs;
wherein the control message includes control information for each of the plurality of TBs and includes hybrid automatic repeat request (H-ARQ) information associated with the TBs; wherein the H-ARQ information includes a redundancy version for each of the TBs; and
in response to the received control message, receive the plurality of TBs in one transmission time interval (TTI).
11. The WTRU of claim 10 , wherein the receiver is further configured to receive a separate cyclic redundancy check (CRC) for each of the plurality of TBs.
12. The WTRU of claim 10 further comprising:
a transmitter configured to transmit combined feedback for the plurality of TBs.
13. The WTRU of claim 10 , wherein the control message includes a transport block size for each of the TBs.
14. The WTRU of claim 10 , wherein the control message includes a modulation and coding scheme for each of the TBs.
15. A method for receiving multiple transport blocks (TB)s by a wireless transmit/receive unit (WTRU), the method comprising:
receiving, by the WTRU, a control message associated with a plurality of TBs; wherein the control message includes control information for each of the plurality of TBs and includes hybrid automatic repeat request (H-ARQ) information associated with the TBs; wherein the H-ARQ information includes a redundancy version for each of the TBs; and
in response to the received control message, receiving, by the WTRU, a plurality of TBs simultaneously in one transmission time interval (TTI).
16. The method of claim 15 , wherein the control message includes a modulation and coding set for each of the TBs.
17. The method of claim 15 , wherein a separate cyclic redundancy check (CRC) is received for each of the plurality of TBs.
18. The method of claim 15 further comprising:
transmitting combined feedback for the plurality of TBs.
19. The method of claim 15 wherein the control message includes a transport block size for each of the plurality of TBs.
20. The method of claim 15 wherein the control message includes an indicates a modulation scheme for each of the plurality of TBs.
21. The method of claim 15 further comprising:
transmitting, by the WTRU, combined feedback for the plurality of TBs.