Enhancing the Performance of Advanced Fiber Communication Systems Using Probabilistic Constellation Shaping

Abstract

The aim of this work is to investigate how the probabilistic constellation shaping (PCS) technique is helpful in meeting the requirement of high traffic demand in coherent fiber communication (CFC) systems. The concepts of building an accurate and realistic simulation model of a long-haul CFC system implemented with PCS technique are presented using VPIphotonic software. The performance of regular (R)- and PCS-MQAM systems is studied in terms of bit error rate (BER) and mutual information (MI) after transmission of a multispan fiber link. The loss and dispersion of the fiber are compensated using in-line erbium-doped fiber amplifier (EDFA) and digital signal processing (DSP) at the receiver side, respectively. Two operating scenarios are used depending on whether optical signal-to-noise ratio (OSNR) or the number of 100 km-spans are used to simulate the transmission link. The effect of symbol rate on both transmission performance is reported for different values of symbol rate (10-50 Gbaud). The results show that the MI of PCS-system overperforms the R-QAM system when the received BER values exceeds 2×10-2 for both 16- and 64-QAM signaling