Blind recognition of retransmitted packets for HARQ system

A simple approach to blindly detect the status of incoming packets (new or retransmitted), in a type-II selective repeat HARQ scheme is presented. Performance results are given showing that the approach is not only able to recognize new from retransmitted packets but also to properly associate retransmitted ones to already stored ones in the receiver, in order to improve the decoding process. Results are given for Rayleigh channel and turbo-codes. Such method could then save signaling in any systems using HARQ transmission.