基于非相干滤波的新型光电振荡器及其应用研究

Microwave signal generation by using photonic methods has attracted much research attentions due to its inherent advantages, such as large bandwidth, low loss, cost-effective, the immunity to electromagnetic intereference, and also the capability of overcoming the drawbacks of electronic generation technology. Optoelectronic oscillator is a new class of technique for the photonic generation of microwave signals, by which we can realize miniature sources of high-frequency microwave signals with exceptional spectral purity and narrow linewidth. In this project, a systematical study of novel optoelectronic oscillators based on incoherent microwave photonic filters will be carried out both theoretically and experimentally. Incoherent microwave photonic filters exhibit good performance on stability, tunibility and configurability, etc. Specially designed and optimized incoherent microwave photonic filters with high Q factor, high extinction ratio, as well as wideband tunibility and configruability will be incorporated into the optoelectronic oscillator loop in order to selete desired frequencies and suppress unwanted noises. The theoretical model for phase noise and stability mechanism of the proposed optoelectronic oscillator will be carried out, base on which the generation signal performance will be further improved to realize the a tunable microwave signal generation with high frequency and low phase noise. Furthermore, based on the advantages of the optoelectronic oscillators, especially its high spectral purity, we will exploit the application of our proposed optoelectronic oscillator in fiber sensing area by employing sensitive and dispersive elements. This project is a multidiscipline study related to several research areas, such as optoelectronics, electromagnetic fields and technologies, and fiber sensing, etc., which will be useful for the development of high frequency and low noise optoelectronic oscillators and broadening their applications.

采用光学方法来产生微波信号能有效地克服电学方法产生微波信号技术的不足，而光电振荡器是一种新的微波信号光学产生技术，能够获得高频谱纯度的微波信号，这种方法在相关领域具有潜在的应用前景。本项目拟将微波光子滤波技术应用于光电振荡器环路来产生高频率低相位噪声的可调微波信号。构建具有高Q值和抑制比、宽带可调谐和可重构的非相干微波光子滤波器，并将其应用于光电振荡器环路，进行边模抑制从而实现光电振荡器的单模起振，同时对环路噪声进行有效抑制；通过对该光电振荡器的相位噪声模型和稳定机制的研究，进一步优化器件参数特性，改善输出信号性能，实现高频率低相位噪声的可调谐微波信号产生。在此基础上，通过引入敏感元件，利用光电振荡信号频谱纯净度好的优越特性，进而探索新型光电振荡器在光纤传感领域的应用。本项目的研究将有助于发展新型高频低相位噪声的光电振荡器并拓展其具体应用。

采用光学方法来产生微波信号能有效地克服电学方法产生微波信号技术的不足，光电振荡器是一种新型的微波信号光学产生技术，能够获得高频谱纯度的微波信号，因而具有潜在的应用前景。本项目采用非相干微波光子滤波技术对光电振荡器环路中的谐波进行选频，从而产生所需频率的微波信号，并研究其应用。在本项目中，分别对非相干微波光子滤波器、光电振荡器进行了理论和实验研究，设计并在实验中实现了双通带可调谐及可切换的非相干微波光子滤波器，实验中搭建了光电振荡环路并进行了优化；将非相干微波光子滤波器（包括光纤环微波光子滤波器和双抽头微波光子滤波器）应用于光电振荡环路，实现了有效的谐波抑制；研究了基于非相干微波光子滤波器（光纤环微波光子滤波器、双通带微波光子滤波器）的微波信号倍频技术，实现了可调谐、可切换的微波倍频信号产生；另外，还研究了光电振荡器在传感方面的应用，实现了基于光电振荡器的可定制灵敏度的温度传感及其解调。通过本项目取得了一些学术成果，发表相关SCI国际期刊论文6篇，EI期刊论文2篇，国际会议论文3篇；申请国家发明专利4项，其中获批2项。参加国际和国内会议交流4人次，其中邀请报告1次（EMN MEETING ON OPTOELECTRONICS 2015）；通过本项目培养博士生/硕士生4人。本项目按照计划执行，完成了预期目标。