SELECTIVE HARQ COMBINING SCHEME FOR OFDM/OFDMA SYSTEMS

摘要

A method and apparatus for combining retransmitted hybrid automatic repeat-request (HARQ) messages at different stages in an orthogonal frequency-division multiplexing (OFDM)/orthogonal frequency-division multiple access (OFDMA) receiver are provided. The type of HARQ combiner used for a particular channel may depend on a number of selection criteria including the modulation order of the transmission, the number of bits needed for the combined signals, and the headroom in the HARQ buffer. For some embodiments, a combination of different types of HARQ combiners may be designed into a receiver and selected on a per-channel basis. Proper selection of a HARQ combining scheme may reduce the required HARQ buffer size and may provide an increased combining gain when compared to conventional HARQ combining techniques.