초록 ▼

A rate-adaptive method of communicating over a multipath wireless communication system uses multiple links such that each end of a link uses multiple transmit and receive antennas. A number of independent streams that are to be transmitted for each link is determined based on an overall system perfo

A rate-adaptive method of communicating over a multipath wireless communication system uses multiple links such that each end of a link uses multiple transmit and receive antennas. A number of independent streams that are to be transmitted for each link is determined based on an overall system performance measure. In addition, the system may also jointly determine the best modulation, coding, power control, and frequency assignment for each link, based on an overall system performance measure. In OFDM systems, the number of independent streams, as well as the modulation, coding, and power control, may be determined on a tone-by-tone basis based on an overall system performance measure.

대표청구항 ▼

What is claimed is: 1. A rate-adaptive method of communicating over a wireless communication system, the wireless communication system including a first station having multiple transmit antennas and multiple receive antennas and a second station having multiple transmit antennas and multiple receiv

What is claimed is: 1. A rate-adaptive method of communicating over a wireless communication system, the wireless communication system including a first station having multiple transmit antennas and multiple receive antennas and a second station having multiple transmit antennas and multiple receive antennas, the method comprising steps of: (a) transmitting a signal in a first frame from the first station to the second station using one of a single transmit antenna of the first station and multiple transmit antennas of the first station with transmission diversity; (b) receiving a second frame from the second station at the first station, the second frame including an indication that at least one additional signal should be transmitted in the third frame; (c) transmitting a predetermined number of signals in the third frame from the first station to the second station when the second frame includes the automatic retransmission request instruction, the predetermined number of signals being transmitted using a corresponding predetermined number of transmit antennas of the first station, the predetermined number of signals being based on the indication received from the second station that at least one additional signal should be transmitted in the third frame; (d) receiving a fourth frame from the second station at the first station, the fourth frame including an indication of a number of signals that should be transmitted from the first station to the second station in a fifth frame in a control sequence of the fourth frame; and (e) repeating each step continuously from step (b) when a number of transmitted signals in the frame transmitted from the first station to the second station is one; otherwise repeating each step continuously from step (c). 2. The method according to claim 1, wherein the indication received in the second frame is based on an overall system performance measure. 3. The method according to claim 2, wherein the overall system performance measure is based on an overall system throughput. 4. The method according to claim 2, wherein the overall system performance measure is based on a minimum of a maximum delay for all links in the wireless communication system. 5. The method according to claim 2, wherein the overall system performance measure is based on a maximum of a minimum data rate for all links in the wireless communication system. 6. The method according to claim 2, wherein the overall system performance measure is based on an SINR associated with the first frame. 7. The method according to claim 2, wherein the overall system performance measure is based on a minimum mean-square error associated with the first frame. 8. The method according to claim 1, wherein the fourth frame further includes an indication of a modulation method that is to be used for each signal transmitted in the fifth frame. 9. The method according to claim 1, wherein the fourth frame further includes an indication of a coding scheme that is to be used for each signal transmitted in the fifth frame. 10. The method according to claim 1, wherein the fourth frame further includes an indication of a coding rate that is to be used for each signal transmitted in the fifth frame. 11. The method according to claim 1, wherein the first station is a base station, the second station is a mobile station, the first, third and fifth frames are downlink frames, and the second and fourth frames are uplink frames. 12. The method according to claim 1, wherein the first station is a mobile station, the second station is a base station, the first, third and fifth frames are uplink frames, and the second and fourth frames are downlink frames. 13. A rate adaptive method of communicating over a wireless communication system, the wireless communication system including a first station having multiple transmit antennas and multiple receive antennas and a second station having multiple transmit antennas and multiple receive antennas, the method comprising steps of: (a) receiving a signal at the first station from the second station using all of the receive antennas of the first station for CCI suppression; (b) computing at the first station a best weight for each receive antenna based on the received signal; (c) generating a composite signal that is based on a weighted summation of all received signals, each respective received signal being received by a receive antenna of the first station; (d) decoding the composite signal for obtaining a payload sequence, a CRC sequence, and a control sequence contained in the composite signal; (e) setting an automatic retransmission request instruction in a control sequence of a second frame to indicate a third frame should be transmitted from the second station when the decoded CRC sequence matches the CRC sequence computed from the decoded payload sequence; (f) setting at least one index corresponding to each signal sequence for retransmission in the automatic retransmission request instruction in the control sequence of the second frame when the decoded CRC sequence does not match the CRC sequence computed from the decoded payload sequence; (g) determining whether at least one additional signal should be transmitted by the first station in the third frame based on an overall system performance measure; (h) transmitting the second frame from the first station to the second station, the second frame including an indication of the determination whether at least one additional signal should be transmitted from the second station in the third frame; (i) receiving at the first station a predetermined number of transmitted signals in the third frame using a corresponding predetermined number of the receive antennas of the first station, the predetermined number of signals being based on the indication transmitted in the second frame; (j) computing at the first station a best weight for each receive antenna for the predetermined number of received signals; (k) generating a composite signal that is based on a weighted summation of a predetermined number of all received signals, each respective received signal of the predetermined number of received signals being received from a receive antenna of the first station; (l) decoding the composite signal that is based on the weighted summation of the predetermined number of all received signals for obtaining a payload sequence, a CRC sequence, and a control sequence contained in the composite signal that is based on the weighted summation of the predetermined number of signals; (m) setting an automatic retransmission request instruction in a control sequence in a fourth frame to indicate a fifth frame should be transmitted when the decoded sequence matches the CRC sequence computed from the decoded payload sequence of the composite signal; (o) setting at least one index corresponding to each signal sequence that should be retransmitted in the automatic retransmission request instruction in the control sequence of the fourth frame when the decoded CRC sequence of the composite signal does not match the CRC sequence computed from the decoded payload sequence contained in the composite signal that is based on the predetermined number of weighted signals; (p) estimating at the first station a predetermined number of signals that should be transmitted from the second station in the fifth frame; (q) transmitting from the first station to the second station the estimated number of signals to be transmitted in the fifth frame in a control sequence of the fourth frame; and (s) repeating each step continuously from step (a) when a number of transmitted signals in the frame transmitted from the first station to the second station is one; otherwise repeating each step continuously from step (i). 14. The method according to claim 13, wherein the indication transmitted in the second frame is based on an overall system performance measure. 15. The method according to claim 14, wherein the overall system performance measure is based on an overall system throughput. 16. The method according to claim 14, wherein the overall system performance measure is based on a minimum of a maximum delay for all links in the wireless communication system. 17. The method according to claim 14, wherein the overall system performance measure is based on a maximum of a minimum data rate for all links in the wireless communication system. 18. The method according to claim 14, wherein the overall system performance measure is based on an SINR associated with the first frame. 19. The method according to claim 14, wherein the overall system performance measure is based on a minimum mean-square error associated with the first frame. 20. The method according to claim 13, wherein the first station is a base station, the second station is a mobile station, the first, third and fifth frames are downlink frames, and the second and fourth frames are uplink frames. 21. The method according to claim 13, wherein the first station is a mobile station, the second station is a base station, the first, third and fifth frames are uplink frames, and the second and fourth frames are downlink frames.