Pulse Amplitude Shaping for QAM and PAM Modulation Schemes

Probabilistic pulse amplitude shaping (PAS) is demonstrated for QAM and PAM modulation schemes for single and dual polarization. The PAS scheme can be used for standard and nonstandard PAMm techniques where m is an integer that could be 3, 4, 5, 6, and 8, or user defined bit-to-symbol mapping. Polarization compensation exploiting signal manipulation in the Stokes space is applied for the dual-polarization multiplexed signals. Local and global optimization algorithms are implemented to allow users find optimum parameters for adaptive equalization in the DSP.