Li Xing, Zhang Siteng, Li Shuguang, Chen Jianping, Zou Weiwen
Opt Lett. 2020 Oct 15;45(20):5736-5739. doi: 10.1364/OL.405640.
Linearly chirped signals with long temporal duration are generated by adding a dispersive loop in the photonic time-stretched coherent radar. The signal-to-noise ratio (SNR) variation of the optical pulse recirculation is analyzed and simulated to evaluate the multiple extension of temporal duration. The achievable temporal duration is confined by the dispersion and the amplified spontaneous emission noise accumulation. The experimental results verify the SNR variation of the optical pulse recirculation. Moreover, tunable linearly chirped signals with temporal duration of 100 ns and a bandwidth of 4 GHz at X or Ku band are generated. With the improvement of the time-bandwidth product, a drone can be successfully observed.
通过在光子时间拉伸相干雷达中添加色散环来生成具有长时间持续时间的线性啁啾信号。分析并模拟了光脉冲再循环的信噪比（SNR）变化，以评估时间持续时间的多重扩展。可实现的时间持续时间受色散和放大自发辐射噪声积累的限制。实验结果验证了光脉冲再循环的SNR变化。此外，还生成了在X或Ku波段具有100 ns时间持续时间和4 GHz带宽的可调谐线性啁啾信号。随着时间带宽积的提高，能够成功观测到无人机。
