Massive Point-by-Point Temporal Pulse Shaping for Ultra-High-Speed and Long-Time-Duration Arbitrary Microwave Waveform Generation

Massive point-by-point temporal pulse shaping to generate ultra-high-speed and long-time-duration arbitrary microwave waveforms based on a temporal Vernier caliper is reported. The temporal Vernier caliper is implemented using a mode-locked laser (MLL) and a fiber loop. The period of a mode-locked pulse train is considered as the main temporal scale division, while the round-trip time of the fiber loop serves as the temporal Vernier scale division. A slight detuning and interpolation between the two temporal divisions result in a small temporal interval, enabling the generation of arbitrary microwave waveforms with a high sampling rate. By temporal duplication of the input pulse, massive temporal pulse shaping with an increased number of points can be realized, enabling the generation of arbitrary microwave waveforms with an extended time duration and increased memory depth. The approach is evaluated experimentally. Analog waveforms at a sampling rate of up to 1 tera-sample-per-second (TSa/s) and communication signals (OOK and PAM4) with a large memory depth of 10.4 kilo-points (kpts) are experimentally generated.