Design of modulated signal waveform in fully digital programmable optical frequency comb

Abstract

AbstractThis paper presents a new design method of digital baseband signal for generating fully digital programmable optical frequency comb (OFC), which solves the problem of how to optimally select the digital baseband signal when OFC is generated by binary digital signal modulation. The inverse Fourier transform is used to study the waveform of binary digital signal which is used to generate OFC. It is found that the number of “0” bits of digital signal determines the flatness of comb lines. Based on this, a tunable ultra‐fine and ultra‐flat OFC was obtained by using a digital signal containing a large number of “0” bits in the experiment. This saves substantial computing time and resources compared to the current method of the k‐means clustering algorithm.