Multi-band multi-format switchable microwave waveforms generation based on an AML-OEO

We present a photonic-assisted multi-band multi-format microwave waveforms generator through polarization manipulation of the optical signal. By constructing an active mode-locking optoelectronic oscillator (AML-OEO), simultaneous multi-frequency oscillation in the loop is realized compared to the traditional OEO. Besides, by applying electrical baseband signals with different formats to the modulator, the recovered microwave waveforms can be switched between phase-coded and dual-chirp signals, which is meaningful for radar systems to realize multi-scene application ability. In addition, the generated binary phase-coded waveforms are in pulse mode, and an accurate π phase jump can be obtained with no need for controlling the amplitude of the baseband signal carefully, which brings great convenience in realistic applications. Furthermore, the RF signals provided by the AML-OEO substitute external high-frequency microwave source in our scheme, ensuring that RF signals in the high-frequency range have better phase noise performance. The proposed approach is theoretically analyzed and experimentally demonstrated.