An efficient ARQ scheme using soft output demodulation in Rayleigh fading channel
نویسندگان
چکیده
An automatic repeat request (ARQ) scheme using rate compatible trellis coded modulation, pilot symbol aided channel estimation, soft output packet combining, and a retransmission request strategy supporting a variable quality of service within a packet is proposed. Simulation results show that this type II hybrid ARQ has about 3–5 dB SNR gain over its type I ARQ counterpart. Keywords— Hybrid ARQ, Rate Compatible TCM, Code Combining, Soft Output Demodulation.
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