Fig. 1. Schematic diagram for pulsed microwave waveform generation based on spectral shaping and FTTM.

Fig. 2. Proposed scheme for background-free pulsed microwave signal generation. MLL, mode-locked laser; PC, polarization controller; DGDE, differential group delay element; DE, dispersive element; PBS, polarization beam splitter; BPD, balanced photodetector; OSC, oscilloscope; ESA, electrical spectral analyzer.

Fig. 3. Simulation results for the generation of a Gaussian-shaped microwave pulse. Waveforms generated by (a) single-end detection and (b) balanced detection; (c) shows the corresponding electrical power spectra.

Fig. 4. Optical spectra (a) before the PBS and (b) at the two outputs of the PBS.

Fig. 5. Measured waveforms of the generated microwave pulses obtained by (a) single-end detection using the BPD and (b) balanced photodetection.

Fig. 6. Electrical power spectra of the pulsed microwave signals obtained by (a) single-end and (b) balanced detection.

Fig. 7. Waveforms and electrical spectra of the pulsed microwave signals at (a) and (b) PMF=6.5  m, SMF=5.88  km and (c) and (d) PMF=12.4  m, SMF=7.8  km.