Receiver design for type-I hybrid ARQ scheme in frequency-selective fading channels

This paper proposes a new receiver design for a type-I hybrid automatic repeat request (ARQ) scheme in wireless packet data services. To achieve reliable transmission under a multipath fading channel environment, temporal diversity from retransmissions is utilized to facilitate channel equalization and error correction via low density parity check (LDPC) codes. A linear equalization receiver structure and an iterative interference cancellation receiver structure are investigated separately. Moreover, three different channel estimation schemes are discussed and their impact on throughput performance are demonstrated.