Frequency-doubled triangular-shaped waveform generation based on spectrum manipulation

In this approach, spectrum manipulation is employed in triangular-shaped waveform generation. By aligning the power of five primary modulation sidebands, optical intensity with expression corresponding to the first two-term Fourier expansion of triangular-shaped waveform can be obtained. It is found that the modulation index in this Letter is no longer a fixed one, but should be within a proper range (2-3). Triangular-shaped waveform signals can be generated by using a single-drive Mach-Zehnder modulator, a standard optical interleaver, and a grating. The principle is illustrated by theory, simulation, and experiment. A 20 GHz triangular-shaped waveform signal is experimentally generated by using a 10 GHz sinusoid signal, which agrees well with the theoretical prediction and shows great potential in generating a high-quality intensity profile.