In the context of short-reach data-center interconnect, such as OIF 400ZR, we study the system impact of bandwidth loss of Silicon Photonics Mach-Zehnder modulators in high-speed coherent modems. As well, we propose a minimum-mean square gradient-descent based method to optimize the compensation of such loss at both transmitter and receiver signal processing finite-impulse response filters. The method improves required-optical signal to noise ratio (ROSNR), under realistic hardware restrictions such as implementation noise and clock jitters at data converters, by 0.5 dB compared to fully pre-compensating the frequency response. Other advantages, such as lower power consumption, are highlighted as well.
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