We propose and demonstrate a photonic approach to generate and transmit a quadrupling-bandwidth dual-chirp microwave waveform with anti-dispersion transmission. Commonly, dual-chirp microwave waveforms are generated by double-sideband modulation, which brings severe chromatic-dispersion-induced power fading (CDIP) over fiber transmission. In this scheme, we perform optical carrier suppression via a polarization controller based on an integrated polarization-division multiplexing Mach–Zehnder modulator (PDM-MZM) to eliminate the CDIP. Moreover, by properly adjusting two bias voltages of PDM-MZM, we find that the bandwidth of the generated dual-chirp microwave signal is quadrupled. It is worth mentioning that we just need to operate in the central office to realize the above-mentioned functions and no optical filters are needed, which significantly improves the limitation of the devices. The method is analyzed theoretically and proved experimentally, which is of great significance for improving range-Doppler resolution and the detection capability of radars for one-to-multi base stations over fiber transmission.

中文翻译：

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基于偏振分频多路复用马赫曾德尔调制器的四倍频双线性调频微波波形的产生和抗色散传输

我们提出并演示了一种光子方法，以产生和传输具有反色散传输的四倍带宽双线性调频微波波形。通常，双线性调频微波波形是由双边带调制产生的，通过光纤传输会带来严重的色散引起的功率衰减（CDIP）。在该方案中，我们通过基于集成的偏振分频多路复用马赫曾德尔调制器（PDM-MZM）的偏振控制器执行光载波抑制，以消除CDIP。此外，通过适当地调整PDM-MZM的两个偏置电压，我们发现所生成的双线性调频微波信号的带宽是原来的四倍。值得一提的是，我们只需要在中心办公室进行操作即可实现上述功能，而无需任何滤光片，这大大改善了设备的局限性。该方法经过理论分析和实验验证，对于提高测距多普勒分辨率和通过光纤传输的一对多基站雷达的检测能力具有重要意义。