中心博士生杨涌澜的工作——“Enhancement of time-delay measurement accuracy of an insufficient stimulated Brillouin scattering based pulse compression system via lock-in detection”（利用不充分受激布里渊散射原理和锁定检测方法对基于脉冲压缩的延时测量技术的优化）的相关成果近期被Optics Express期刊接收，该工作得到了国家重点研发计划（2019YFB2203700）、国家自然科学基金（61822508）的部分资助。该工作通过建立雷达回波信号延时与SBS脉冲压缩增益之间的联系，检测脉冲压缩增益并反演计算得到回波信号的延时信息。此外，利用锁相检测方法对探测端的脉冲压缩增益进行积累，进一步降低对系统采样率的要求，减少噪声引入的系统抖动和增益衰减。实验采用带宽为1GHz的线性调频信号进行验证，延时测量精度约为1ns。该方案为未来实现快速实时测量回波信号延时提供了可能性。
摘要: We demonstrate a novel scheme to increase the accuracy of time-delay measurement of an insufficient stimulated Brillouin scattering (ISBS) based pulse compression system. It is realized by relating the time delay with the pulse compression gain, which is accumulated by a lock-in amplifier (LIA). We theoretically demonstrate that the time delay is proportional to the accumulated gain via the LIA. In the experiment, the pulse compression gain is accumulated through lock-in detection. It narrows down the detection bandwidth and reduces the influence from the broadband noise. The time-delay measurement is completed in a real-time manner and thus provides a possible solution to realizing a high-speed process in the future. The accuracy of measurement of a linear frequency modulated (LFM) signal with a bandwidth of 1 GHz is 1 ns.