Methods and apparatus for multi-carrier communication systems with automatic repeat request (ARQ)
Hybrid ARQ is employed in a multi-carrier communication system for retransmission of erroneous packets by taking advantage of time/frequency/space diversity and by combining ARQ functions at physical layer and MAC layers, making the multi-carrier system more robust in a high packet-error environment.
1. A method for a transceiver in a wireless communication system, the method comprising:
transmitting a data packet over a first subchannel to a receiver;
receiving a signal from the receiver; and
if the signal from the receiver indicates an error in the transmission of the data packet over the first subchannel, transmitting a redundancy version of the data packet to the receiver over a second subchannel and transmitting another data packet previously scheduled for the second subchannel over the first subchannel, wherein the second subchannel has a better channel quality for the receiver than the first subchannel.
2. The method of claim 1 , further comprising receiving a channel quality indicator (CQI) from the receiver.
3. The method of claim 2 , wherein the CQI is received with the signal from the receiver at substantially the same time.
4. The method of claim 1 , wherein the transmission over the first or second subchannel uses an adaptive modulation and coding scheme.
5. The method of claim 1 , wherein the transmission over the second subchannel uses a same modulation scheme as the transmission over the first subchannel.
6. The method of claim 1 , wherein the redundancy version of the data packet is a progressive parity packet of the data packet.
7. A wireless communication system comprising a transceiver configured to:
transmit a data packet over a first subchannel to a receiver;
receive a signal from the receiver; and
if the signal from the receiver indicates an error in the transmission of the data packet over the first subchannel, transmit a redundancy version of the data packet to the receiver over a second subchannel and transmit another data packet previously scheduled for the second subchannel over the first subchannel, wherein the second subchannel is has a higher better channel quality for the receiver than a channel quality of the first subchannel.
8. The system of claim 7 , wherein the transceiver is further configured to receive a channel quality indicator (CQI) from the receiver.
9. A method for a transceiver in a wireless communication system, the method comprising:
receiving a data packet over a first subchannel from a transmitter;
transmitting a signal to the transmitter; and
if the signal to the transmitter indicates an error in the transmission of the data packet over the first subchannel, receiving a redundancy version of the data packet from the transmitter over a second subchannel and receiving another data packet previously scheduled for the second subchannel over the first subchannel, wherein the second subchannel has a better channel quality for the transceiver than the first subchannel.
10. The method of claim 9 , further comprising transmitting a channel quality indicator (CQI) to the transmitter.
11. The method of claim 10 , wherein the CQI is transmitted with the signal to the transmitter at substantially the same time.
12. The method of claim 9 , wherein the reception over the first or second subchannel uses an adaptive modulation and coding scheme.
13. The method of claim 9 , wherein the reception over the second subchannel is based on a same modulation scheme as the reception over the first subchannel.
14. The method of claim 9 , wherein the redundancy version of the data packet is a progressive parity packet of the data packet.
15. A wireless communication system, the wireless communication system comprising a transceiver configured to:
receive a data packet over a first subchannel from a transmitter;
transmit a signal to the transmitter; and
if the signal to the transmitter indicates an error in the transmission of the data packet over the first subchannel, receive a redundancy version of the data packet from the transmitter over a second subchannel and receive another data packet previously scheduled for the second subchannel over the first subchannel, the second subchannel containing a second group of subcarriers, wherein the second subchannel has a better channel quality for the transceiver than the first subchannel.
16. The system of claim 15 , wherein the transceiver is further configured to transmit a channel quality indicator (CQI) to the transmitter.
17. The system of claim 16 , wherein the CQI is transmitted with the signal to the transmitter at substantially the same time.
18. The system of claim 15 , wherein the reception over the first or second subchannel uses an adaptive modulation and coding scheme.
19. The system of claim 15 , wherein the redundancy version of the data packet is a progressive parity packet of the data packet.