可调光纤延迟线不仅是未来全光网络中的关键器件，而且在光信号处理和微波光子学等领域有着极其重要的用途。基于布里渊散射效应（SBS）实现可调光纤延迟线是近年来发展起来的一门新兴的可调光延迟技术，具有泵浦光功率阈值低、工作波长可调谐、室温下工作以及与光纤通信系统兼容性好等优点。但SBS增益谱带宽较窄，且布里渊频移受限，斯托克斯光脉冲获得延迟的同时存在严重失真，无法满足宽带系统的应用要求。 本项目从宽带光泵浦的 SBS 理论出发，研究提高延迟-带宽积物理方法；基于光注入半导体激光器产生的周期振荡作为多谱线泵浦光，探索拓展微波信号带宽、提高微波信号频率的可调谐延迟机理；通过构建高精度光纤延迟线实验系统，实现连续可调谐微波信号的最小畸变延时。本项目的研究结果为实现宽带高频可调谐的光纤延迟线系统提供了一条新的研究思路，对于灵活实现光信号存储与处理、高精度光控相控阵雷达奠定了理论与应用基础。

Tunable fiber-optic delay line is not only the key component in future all-optical network, but also plays a critical role in optical signal processing and microwave photonics. Recently, stimulated Brillouin scattering (SBS), as a promising technique, has been developed to realize tunable fiber-delay lines, which has the advantages of low pump power with tunable wavelength and is compatible with the existing telecommunication technology. Moreover, the process can be achieved at room temperature. However, the narrow gain bandwidth and the limited SBS frequency shift induce serious distortion on the delayed optical pulses. It is impossible to be applied to wideband systems. Based on the theory of wideband pump signal of SBS, this proposal will conduct research on the physical method to improve the product of delay time and bandwidth; and explore the principle of tunable fiber-delay line for wideband and high frequency microwave signal by using the periodic oscillations generated from optically injected laser system. The related studies will be applied to realize continuously tunable fiber-optic delay lines with minimized distortion on microwave signals . The outcomes of the proposal will provide a novel option for wideband high frequency fiber-optic delay lines and have theoretical instructions to solve all optical routing and high precision phase-array antenna radar systems.