Photonic generation of quadruple bandwidth dual-band dual-chirp microwave waveforms with immunity to power fading

A photonic method to generate and transmit quadruple bandwidth dual-band dual-chirp microwave waveforms with immunity to fiber chromatic dispersion induced power fading is proposed and experimentally demonstrated, which is suitable for Doppler blind–speed elimination, small target detection, and multiband detection in multiband radar systems. A dual-polarization dual-parallel Mach–Zehnder modulator is utilized to realize carrier-suppressed harmonic single-sideband modulation of a radio frequency carrier and carrier-suppressed DSB modulation of a baseband single-chirped waveform at two orthogonal polarization states. After photoelectronic conversion, dual-band bandwidth-quadrupling dual-chirp waveforms are generated. Moreover, different from traditional DSB-based dual-chirp signal generation, the generated dual-chirp microwave waveforms can be transmitted over fiber without power fading, which is significant in dual-band radars for one to multiple base station transmissions.