Performance Analysis of Circle-Constellation-Based M-DCSK Modulation for Broadcasting Application with Enhanced Reliability by LDPC

Abstract

In this paper, a circle-constellation-based M-ary differential chaos shift keying (M=8;8-DCSK) is proposed for broadcasting application, such as digital video broadcasting (DVB), rather than coherent amplitude phase shift keying (APSK) which implementation is much complex because of the necessity of synchronous demodulation at the receiver. In addition, low density parity check (LDPC) which can denote the effective reduction of bit error rate (BER) by an iteration decoding algorithm is also deployed in the proposed system to overcome the degradation of BER performance which results from the channels nonlinearity and the effect of natural or man-made noises, such as additive white Gaussian noise (AWGN) or partial band noise jamming (PBNJ). From the computer simulation results, the proposed regular and irregular LDPC-coded 8-DCSK requires merely $-27\mathrm{d}\mathrm{B}$ power to retain the BER in the range of $10^{-1}\sim 10^{-3}$ under AWGN and PBNJ with $\rho=0.5$.