Patent ID: 7652977
Filing Date: 2010-01-26
Classification: H04L

Abstract:
1. A Hybrid Automatic Repeat Request (HARQ) combining method in an Orthogonal Frequency Division Multiplexing (OFDM) system, comprising steps of: a. a transmitter transmitting data to a receiver in a unit of frame, then the receiver weighting the received data based on its SNR and variance of SNR and storing the weighted data as final data in a buffer of a HARQ combining unit, and later, the receiver processing the stored final data to determine whether the received data frames are correct; b. if the data frames are correct, the receiver outputting the final data and feeding back an ACK indicator respectively to the HARQ combining unit of the receiver and the transmitter, and if the data frames are not correct, the receiver feeding back a NACK indicator respectively to the HARQ combining unit of the receiver and the transmitter; c. when the HARQ combining unit of the receiver and the transmitter receiving an ACK indicator, the process returning to step a, until all data has been transmitted; d. when the HARQ combining unit of the receiver and the transmitter receiving a NACK indicator, the transmitter retransmitting original data to the receiver, then the HARQ combining unit of the receiver weighting the received retransmission data based on its SNR and variance of SNR, and combining the weighted retransmission data with the data stored in the buffer of the HARQ combining unit, and at the same time, storing the combined data as final data in the buffer of the HARQ combining unit, then the receiver processing the combined final data to determine whether the combined data frames are correct, after that, the process returning to step b.