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Design of LDPC Encoder and Decoder for 40 Gb/s Optical Communication Systems

Prabhmandeep Kaur, Divya Dhawan

Abstract


 

This paper presents a design approach for low-density parity-check (LDPC) encoder and decoder for applications in optical communication systems at 40 Gb/s. In order to get the best performance, the system is further optimized for the powers of the EDFA (Erbium Doped Fiber Amplifier) amplifiers used with the SMF (Single Mode Fiber) and DCF (Dispersion Compensating Fiber) fibers to achieve the highest Q factor. The designed LDPC coded system (using LDPC codes of r=0.8 for coding and sum-product algorithm (SPA) for decoding) is compared with the uncoded system at bit rate of 40 Gb/s and seen to provide significant performance improvement in terms of the BER. LDPC codes also provide near-capacity performance and significant system enhancement with respect to the state-of-the-art FEC (Forward Error Correction) schemes. High coding gains and their inherent low complexity of both the encoder and decoder have made them an attractive and viable choice for high-speed optical communication.


Keywords


Forward Error Correction (FEC), Low Density Parity Check (LDPC) Codes, Sum Product Algorithm (SPA).

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References


O. Milenkovic, I. B. Djordjevic, and B. Vasic, “Block-circulant lowdensity parity-check codes for optical communication systems,” IEEE/ LEOS J. Sel. Topics Quantum Electron., vol. 10, pp. 294–299, Mar. 2004.

C. E. Shannon . Certain results in coding theory for noisy channels. Information and Control 1:6-25,1957

R. H. Morelos-Zaragoza, The Art of Error Correcting Coding. Boston,A: Wiley, 2002.

O. A. Sab, “FEC techniques in submarine transmission systems,” in Proc.Optical Fiber Communication Conf., 2001, vol. 2, pp. TuF1-1–TuF1-3.

R. M. Pyndiah, “Near optimum decoding of product codes,” IEEE Trans.Commun., vol. 46, pp. 1003–1010, 1998.

O. A. Sab et al., “Concatenated forward error correction schemes for long-haul DWDM optical transmission systems,” in ECOC, 1999, pp.II–290.

R. G. Gallager, Low Density Parity Check Codes. Cambridge, MA: MIT Press, 1963.

B. Vasic and I. B. Djordjevic, “Low-density parity check codes for long haul optical communications systems,” IEEE Photon. Technol. Lett., vol. 14, pp. 1208–1210, 2002.

B. Vasic, I. B. Djordjevic, and R. Kostuk, “Low-density parity check codes and iterative decoding for long haul optical communication systems,” J. Lightwave Technol., vol. 21, pp. 438–446, 2003.

S. Chung et al., “On the design of low-density parity-check codes within 0.0045 dB of the Shannon Limit,” IEEE Commun. Lett., vol. 5, pp. 58–60, Feb. 2001.

M. Tanner, “A recursive approach to low complexity codes,” IEEE Trans. Inform. Theory, vol. IT-27, pp. 533–547, Sept. 1981.

Ivan B. Djordjevic, Murat Arabaci, , and Lyubomir L. Minkov,” Next Generation FEC for High-Capacity Communication in Optical Transport Networks,” J. Lightwave Technol.,vol.27, pp.3518-3530, August 2009.

W. E. Ryan, “An introduction to LDPC codes,” in CRC Handbook forCoding and Signal Processing for Recording Systems, B. Vasic, Ed.Boca Raton, FL: CRC, 2004.

H. Xiao-Yu et al., “Efficient implementations of the sum-product algorithm for decoding of LDPC codes,” in Proc. IEEE Global Telecommunications Conf. (Globecom’01) Nov. 25–29, 2001, vol. 2, pp. 1036–1036E.

Ivan B. Djordjevic, Sundararajan Sankaranarayanan, Shashi Kiran Chilappagari,and Bane Vasic, “Low-Density Parity-Check Codes for 40-Gb/s Optical Transmission Systems, ” IEEE J. Sel. Topics Quantum Electron., Vol. 12, No. 4, , pp. 555-562, July/August 2006.

I. B. Djordjevic, O. Milenkovic, and B. Vasic, “Generalized low-densityparity-check codes for optical communication systems,” J. Lightw. Technol.,vol. 23, no. 5, pp. 1939–1946, May 2005.


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