Sidelobe Suppression in OFDM Systems using Suitable Map in Constellation Expansion Method
Orthogonal frequency division multiplexing (OFDM) suffers from high out-of-band (OOB) radiation. Constellation expansion (CE) is one of the methods for reduction of OFDM sidelobes that has a good performance. In CE, no side information needs to be transmitted and it doesn’t involve complex optimization problem but, it has an increment in the bit error rate (BER) parameter. In this method, the symbols map to the high order constellation that, the CE performance depends on this map of symbols. The selected map directly affects on sidelobes reduction. In this letter, we compare the different maps in CE method and propose a suitable map that has the best sidelobes reduction. Simulation results show that the proposed map reduces the OFDM sidelobes significantly.
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