基于复合色散傅里叶变换和Talbot效应的可调谐、可重构多载波调频信号光子学产生机理研究

雷达通信一体化是我国军事和民用领域的共性重大需求，低成本高性能多载波调频信号物理实现是雷达通信一体化亟待突破的瓶颈问题。电子学方法生成调频信号频率低、带宽小，多路调频需要多个发射机；微波光子方法可以产生高频、大带宽调频信号，却面临多路扩展困难、可调谐和可重构性能有限、成本高等挑战。本项目针对现有光生调频诸多挑战性问题，深入研究声光频移反馈信号源，修正含环内色散效应的无源腔模型，建立基于频移反馈色散和环内色散效应的新型复合色散傅里叶变换理论；揭示复合色散傅里叶变换和Talbot自成像共存机制，对时空二元性原理中菲涅尔衍射区两种特殊效应进行重要关联和补充，建立Talbot效应调控时域展宽脉冲重复频率的技术方法；低成本单发射机实现可调谐、可重构多载波调频信号。本项目的研究成果将丰富和发展频移反馈环基础理论研究，解决共享波形物理实现限制，为雷达通信一体化演进提供理论指导和技术支撑。

Radar-Communication integration has become a significant national demand in both military and civil areas, and yet the realization of multi-carrier frequency-modulated signal with low cost and high performance is one bottleneck of Radar-Communication integration. Conventional electronic technologies can only generate frequency-modulated signal with low central frequency and small bandwidth, and many transmitters are required to output multiple frequency-modulated signals. Microwave photonic methods can realize frequency-modulated signal with high central frequency and large bandwidth, however suffer from poor scalability of multi-carrier frequency-modulated signals, limited tunability and reconfigurability, and high-cost. This project is going to break through above challenges by deeply exploring frequency-shifted feedback signal generator with acousto-optic frequency shifter. First, the passive cavity model of frequency-shifted feedback signal generator will be rectified by introducing the loop dispersion, and novel complex dispersive Fourier-transform based on frequency-shifted feedback dispersion and loop dispersion will be established. Second, the coexistence of complex dispersive Fourier-transform and Talbot effect will be revealed. As both effects occur in Fresnel diffraction region, their theoretical correlation will be discovered based on space-time duality. Thus, Talbot effect will be utilized to control the repetition rate of temporally stretched pulse. At last, a cost-effective photonic method to achieve tunable and reconfigurable multi-carrier frequency-modulated signals using one transmitter will be proposed. As a result, this project will develop fundamental theoretical research of frequency-shifted feedback loop, overcome the challenging realization of Radar-Communication integrating waveform, and provide theoretical guidance and technical reference for advanced evolution of Radar-Communication integration.