120 GBaud PAM-4/PAM-6 generation and Detection by Photonic Aided Digital-to-Analog Converter and Linear Equalization

In this article, for the first time, we propose a photonic-aided digital-to-analog converter (PA-DAC) to break through transmitter-side bandwidth limitation in intensity modulation and direct detection (IM-DD) systems. By using this method, bandwidth of receiver-side devices can be fully utilized, and nonlinear distortions in high-data-rate electrical signals are avoided. Experimental results show that, with only linear equalization, 120 GBaud PAM-4 and PAM-6 signals have been successfully generated and detected with bite error ratios (BERs) below 6.25%-OH HD-FEC and 20%-OH SD-FEC limits, respectively.