ABSTRACT Based on the constellation diagram of the different modulations, a novel S and Π-decision rule is designed for the analog demapper of the orthogonal frequency-division multiplexing (OFDM) systems. The dedicated short-range communications (DSRC) system is chosen as an OFDM platform to compare the performance among the proposed S and Π-decision decoder, hard-decision and soft-decision decoders. Simulation results demonstrate that both the complexity and performance of S and Π-decision demapper used for M-ary quad-rature amplitude modulation (QAM) OFDM system can be greatly improved. The number of decisions be-tween the received symbol and constellation points can be simplified to look up table times for M-ary QAM OFDM system.
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nullJ. MAR and C. KUO, "Performance Improvement of the DSRC System Using a Novel S and Π-Decision Demapper," Wireless Sensor Network, Vol. 1 No. 4, 2009, pp. 268-275. doi: 10.4236/wsn.2009.14033.
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