ML PAM4 Pre-Emphasis Coefficients Optimization Algorithm for Mitigating Gain Nonlinearity in SOAs

This paper proposes a ML algorithm using stochastic gradient descent (SGD) to optimize PAM4 pre-emphasis to mitigate gain nonlinearity in semiconductor optical amplifier (SOA). Experimental results validate its effectiveness, reducing the power penalty from <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$21 d B$</tex> to <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$4.2 d B$</tex> with 53 GBaud PAM4 data transmission.