Photonic-Based Frequency-Doubling Dual-Band Dual-Chirp Microwave Waveforms Generation and Anti-Dispersion Transmission

We propose and demonstrate a photonic scheme to generate and transmit dual-band dual-chirp microwave waveforms based on a single dual-polarization dual-parallel Mach-Zehnder modulator (DP-DPMZM), which structure is simple and compact. The center frequencies of the generated dual-band dual-chirp signals are frequency-doubling and can be adjusted flexibly and independently to meet the practical requirement of radar systems. Moreover, chromatic dispersion-induced power fading (CDIP) can be eliminated by appropriately adjusting the direct current biases of the modulator to achieve carrier-suppressed single-sideband (CS-SSB) modulation. The proposed method is theoretically analyzed and experimentally proved. Dual-band dual-chirp signals with center frequencies of 12 GHz, 17 GHz, and 8 GHz, 14 GHz are successfully generated. In addition, the signal-to-noise ratios (SNRs) and pulse compression performance of the generated signals are evaluated. The proposed scheme is suitable for dual-band radar systems to conduct target detection, Doppler blind speed elimination, and one-to-multi base station transmission.