Performance Improvement of the DSRC System Using a Novel S and PI-Decision Demapper

Based on the constellation diagram of the different modulations, a novel S and pi -decision rules are designed for the analog demapper of the OFDM systems. The DSRC system is chosen as an OFDM platform to compare the performance among the proposed S and pi -decision decoder, hard-decision and soft-decision decoders. Simulation results demonstrate that both the complexity and performance of S and pi -decision demapper used for M-ary QAM OFDM system can be greatly improved. The number of decisions between the received symbol and constellation points can be simplified to look up table log
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M times for M-ary QAM OFDM system.