Hossain, MM, Islam, MM, Rahman, MS, Islam, MM, and Islam, MS 2010. BER evaluation of low-density parity-check coded OFDM system under different modulation schemes. Inst. eng. tech. 1 (1): 1-4.
In this paper, the impact of low-Density Parity-Check code (LDPC) on the performance of an Orthogonal Frequency Division Multiplexing (OFDM) system under various digital modulations (QPSK, 8PSK, QAM and 8QAM) over an Additive White Gaussian Noise (AWGN) and other fading (Raleigh and Rician) channels is investigated. The study is made with the development of a computer program and its application on the processing of a black and white (monochrome) digital image. Numerical results show that Bit error rate (BER) performance of LDPC coded OFDM system with QAM modulation technique is highly effective to combat inherent interference in the communication system. Due to constraint in data handling capability of the program editor, a black and white image in JPEG is converted into a monochrome BMP format and is used for analysis. The transmitted image is found to have retrieved effectively under noisy and fading situations.