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Frequency-chirped microwave waveforms have high pulse compression ratio and are widely used as radar waveforms to increase the detection range and range resolution. In radar networks, the frequency-chirped microwave waveforms generated in center office (CO) need to be transmitted to remote base stations. During fiber transmission, the dispersion of long-distance fiber may cause power fading to the radar waveforms which restricts the signal frequency, signal bandwidth and transmission distance. In this paper, we review our recent works about photonic generation and antidispersion transmission of frequency chirped microwave waveforms. First, based on polarization multiplexing Fourier mode-locked optoelectronic oscillator, frequency and bandwidth doubling chirped microwave signals are generated. By adding a laser, the system can also generate dual-chirp signals. Second, by combining the generation and transmission of dual-chirp microwave waveforms, we proposed a photonic scheme for the generation and transmission of dual-chirp microwave signals based on shifting the power fading frequency response to compensate the fiber dispersion. In order to further improve the bandwidth of dual-chirp waveforms and the anti-dispersion transmission capability, we used optical frequency doubling and carrier frequency shifting technology to achieve quadruple-bandwidth dual-chirp signal generation and transmission with the elimination of power fading. Moreover, an equivalent splitting parabolic phase modulation scheme was proposed to generate background-free dual-chirp microwave waveforms, which is independent of the direct current bias points of the modulator and the polarization states of the system. The system can eliminate the power fading induced by fiber dispersion in principle, which has good application prospects in radar networks.
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