Method and apparatus for cooperative wireless communications
A method and apparatus for cooperation in wireless communications. Cooperation is considered among a number of network elements, including at least one wireless transmit-receive unit, at least one relay station, and at least one base station.
1. A method for use in wireless communications, the method comprising:
receiving a first portion of a first message from a base station via a first frequency;
receiving a second portion of the first message from at least one relay station of a plurality of relay stations via a second frequency, wherein the second portion originated at the base station and wherein the first portion and the second portion of the first message include cooperation information that includes information related to at least one relay station of the plurality of relay stations to be used for transmission to the base station;
splitting a second message into a first portion and a second portion;
transmitting the first portion of the second message directly to the base station via a third frequency; and
transmitting, based on the cooperation information, the second portion of the second message to the base station via at least one relay station of the plurality of relay stations via a fourth frequency, the at least one relay station selected based in part on the cooperation information.
2. The method of claim 1 , further comprising:
decoding the received first portion of the message;
wherein the second portion of the message is the remaining portion that the WTRU did not decode.
3. The method of claim 2 further comprising:
using a distributed antenna scheme, wherein the WTRU receives different information bits from the base station and the relay station simultaneously; and
the WTRU using successive interference cancellation to distinguish between the different information bits.
4. The method of claim 1 , wherein control information associated with the first message is received from the base station.
5. A method for use in wireless communications, the method comprising:
receiving a first portion of a first message from a base station, the first message intended for a wireless transmit/receive unit (WTRU) wherein a second portion of the first message is sent directly from the base station to the WTRU;
decoding the first message;
recoding the first message;
retransmitting the recoded first message and cooperation information to the intended WTRU, the cooperation information including information related to the relay station; and
receiving, based on the cooperation information, a first portion of a second message from the WTRU, the second message intended for the base station, wherein a second portion of the second message is sent directly from the WTRU to the base station.
6. A wireless transmit/receive unit (WTRU) configured for use wireless cooperative communications comprising:
a receiver configured to:
receive a first portion of a first message from a base station via a first frequency;
receive a second portion of the first message from at least one relay station of a plurality of relay stations via a second frequency, wherein the second portion originated at the base station and wherein the first portion and the second portion of the first message include cooperation information that includes information related to at least one relay station of the plurality of relay stations to be used for transmission to the base station;
a processor configured to split a second message into a first portion and a second portion;
a transmitter configured to transmit the first portion of the second message to the base station via a third frequency and transmit the second portion of the second message to at least one relay station of the plurality of relay stations via a fourth frequency, the at least one relay station selected based in part on the cooperation information.
7. The WTRU of claim 6 , wherein:
the processor is configured to decode the received first portion of the message;
wherein the second portion of the message is the remaining portion that the WTRU did not decode.
8. The WTRU of claim 7 further comprising:
a distributed antenna scheme configured to receive different information bits from the base station and the relay station simultaneously; and
wherein the processor uses successive interference cancellation to distinguish between the different information bits.
9. The WTRU of claim 6 , wherein control information associated with the first message is received, via the receiver, from the base station.
10. A relay station configured for use in wireless cooperative communications comprising:
a receiver configured to receive a first portion of a first message from a base station, the first message intended for a wireless transmit/receive unit (WTRU), wherein a second portion of the first message is sent directly from the base station to the WTRU;
a processor configured to decode and recode the first message;
a transmitter configured to retransmit the recoded first message and cooperation information to the intended WTRU, the cooperation information including information related to the relay station; and
the receiver configured to receive, based on the cooperation information, a first portion of a second message from the WTRU, the second message intended for the base station, wherein a second portion of the second message is sent directly from the WTRU to the base station.