Maximum Likelihood Decoding of Low Density Parity Check Coded Subcarrier Modulation in Optical Wireless Systems

Abstract

We propose low density parity check (LDPC) coded optical wireless communication systems with multiple subcarrier modulation (BPSK and QPSK). Upper bounds on the bit-error rate (BER) for maximum likelihood (ML) decoding of LDPC coded systems have been obtained on atmospheric optical channels where the effects of the scintillation exist. We also show that LDPC coded atmospheric optical systems have better BER than turbo coded atmospheric optical systems