An efficient OFDM-based system with an insufficient cyclic prefix via a novel constellation algorithm

Authors: SAEED GHAZI-MAGHREBI

Abstract: In this paper, a new special triangular constellation scheme is introduced to replace the commonly used rectangular QAM constellation in orthogonal frequency division multiplexing (OFDM) modulation. We have shown that this new scheme has 3 major advantages with respect to the well-known QAM. The first advantage is its lower error probability performance, which results from better usage of the constellation space with longer minimum distances. The 2 other advantages are a lower peak to average power ratio (PAPR) and higher noise immunity. Both mathematical analysis and simulation results demonstrate that by applying standard channels in 2 cases, i.e. channels with AWGN and channels with burst noise and also with intersymbol interference (ISI) impairment simultaneously, the proposed constellation exhibits superior performance compared to the well-known QAM. As a result, this constellation is a good choice for high-speed and real-time OFDM multicarrier applications such as WiFi, WiMAX, DVB, and DAB at no extra cost.

Keywords: Constellation, cyclic prefix, OFDM, QAM, PAPR

Full Text: PDF