Forward Error Correction Codes—Reed–Solomon and LDPC for OFDM Over the Optical Fiber Communication Systems

Abstract

In this paper, authors have compared the performance of two popular optical FEC codes, Reed–Solomon (RS) and low-density parity-check (LDPC), to improve the performance of an OFDM over the optical fiber communication system. Both RS and LDPC codes improve the BER performance at receiver with different laser power levels. For received optical power 3 dBm, RS coded OFDM shows BER (2.32 * 10−14), LDPC coded OFDM shows (1.39 * 10−15), whereas BER recorded for uncoded OFDM for this laser power range is (9.17 * 10−12). Data array size in LDPC is almost two times compared to RS code and uncoded OFDM. Required optical power at receiver (receiver sensitivity) for laser power 0 dBm for uncoded OFDM (18.89 dBm), RS coded OFDM (13.88 dBm) and LDPC coded OFDM (12.69 dBm). LDPC outperforms in almost every aspect like decoder complexity, processing delay, BER and can be selected for improvement in nonlinearity and dispersion issues for closely spaced subcarriers in ODFM for optical fiber.