• V.Bhanupriya
• C.Subhas

Forward Error Correction (FEC) codes are used for error detection and correction in communication systems. Low Density Parity Check (LDPC) codes are used as powerful FEC codes in long distance communication systems which work close to the Shannon limit. Linear LDPC block codes will have sparse parity-check matrices. The decoding algorithm used for LDPC codes is an iterative message passing algorithm (MPA). LDPC codes are used to reduce bit rate error (BER). This paper discusses BER performance of LDPC codes using Binary Phase Shift Keying (BPSK) modulation with different combining techniques used for mitigating the fading effects in Rayleigh channels. Maximal Ratio Combining (MRC) provides excellent reduction in BER as compare to Selection Combining (SC) and Equal Gain Combining (EGC). The simulation results show that with LDPC codes the performance of diversity combining techniques has been improved when compared with uncoded diversity combining techniques. Finally, it is shown that the BER performance of LDPC codes in Rayleigh channels has improved dramatically in the higher SNR region.

LDPC codes, diversity combining, BPSK modulation, Rayleigh fading channel, message passing algorithm.

"performance of LDPC codes in Rayleigh channels", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.5, Issue 7, page no.614-620, July-2018, Available :http://www.jetir.org/papers/JETIR1807096.pdf

"performance of LDPC codes in Rayleigh channels", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.5, Issue 7, page no. pp614-620, July-2018, Available at : http://www.jetir.org/papers/JETIR1807096.pdf