Photonic Generation of Dual-Band Microwave Waveforms with Simultaneous and Diverse Modulation Formats

A photonic method of generating dual-band microwave waveforms with simultaneous and different formats is proposed and experimentally verified using a dual-polarization dual-parallel Mach-Zehnder Modulator (DP-DPMZM). The four sub-MZMs of DP-DPMZM are driven by two independent radio frequency (RF) signals and two independent baseband signals. After photo-detection, two baseband signals are up-converted into two different higher frequency bands. The two RF signals and two baseband signals are utilized to adjust the central frequencies and modulation formats of two frequency bands, respectively. Dual-band phase-coded microwave signal with different bit rates and coding patterns at two different frequency bands, dual-band dual-chirp microwave signal with different chirp rates, and one-band dual-chirp and one-band phase-coded microwave signal are successfully generated in our experiments. The central frequencies of two frequency bands are independently tunable, and the modulation formats of waveforms at two frequency bands can also be diverse, which brings more convenience and feasibility into real-world applications. The flexible tunability in the central frequencies and modulation formats of different frequency bands can meet different requirements for radar and communication systems.