Method for requesting retransmission, method for retransmission and devices thereof

A method for requesting retransmission, method for retransmission and the corresponding transmitter, receiver and system are provided. The method for requesting retransmission includes the following steps: signals from the transmitter are received and whether retransmission is needed is judged; the indication information of whether the transmitter needs to execute retransmission is fed back in a main feedback channel; if retransmission is needed, then retransmission enhancement information is fed back in a second feedback channel associated with the main feedback channel, and the retransmission enhancement information is used for improving the reception quality or the transmission efficiency of retransmission signals. With the technical solution, the quality and efficiency of retransmission can be effectively improved.