Photonic generation of frequency-quadrupled triangular waveform based on a DP-QPSK modulator with tunable modulation index. (May 2021) - Wang, Chuangye
Highlights: We proposed a scheme of triangular waveform generation using DP-QPSK modulator. The repetition rate of triangular waveform is four times the frequency of RF signal. The modulation index of the modulator in this scheme can be tunable. The scheme enables good repetition rate tunability. Abstract: In this paper, a scheme for generating frequency-quadrupled triangular waveform based on a dual-polarization quadrature phase-shift-keying (DP-QPSK) modulator is proposed. The repetition rate of the generated triangular waveform is four times the frequency of radio frequency (RF) signal. In this scheme, the modulation index of modulator is no longer a fixed value, and it can be adjusted in a certain range, which increases the flexibility of the scheme. Compared with previous frequency-quadrupled triangular waveform generation schemes, the structure of this scheme is simple, and the scheme enables good repetition rate tunability. The effect of extinction ratio and DC bias drift of modulator on the scheme is analyzed by simulation.