摘要
在研究MPF(微波光子滤波器)理论的基础上,针对滤波器的整体性能优化和偏振不稳定性,提出了一种基于法拉第旋转镜辅助设计的MPF结构,得到了一个高阶结构的MPF。实现了同时具有高Q值、高边频选择性和高阻带抑制比的可调谐带通滤波器。采用信号流图分析了法拉第旋转镜反射光纤环延迟线结构中微波调制信号的流程,推导出了传递函数、Q值表达式。并进行了仿真,分析了耦合系数、光纤放大器增益和光纤环环长对输出谱特性的影响。
In order to optimize the entire performances of Microwave Photonic Filters(MPF) and their polarization stability,a Faraday spinning mirror-based MPF structure is presented.This tunable bandpass filter has high Q value,high side frequency selection and high stopband suppression ratio.On the basis of the theory of MPF,the microwave modulated signal flow of Faraday spinning mirror assisted Fiber Ring Delay Line(FRDL) is analyzed and the transfer function and the expression of Q value derived by using the signal flow graph.Finally,simulation is conducted and the effects of coupling coefficient,EDFA gain and fiber ring length on the output spectral characteristics analyzed.
引文
[1]Capmany Jose,Dalma Novak.Microwave photonicscombines two worlds[J].Nature Photonics,2007,1(3):319-330.
[2]Capmany Jose,Ortega Beatriz,Pastor Daniel.A tuto-rial on microwave photonic filters[J].LightwaveTechnology,2006,24(1):201-229.
[3]Erwin H,Chan W.High-Order Infinite Impulse Re-sponse Microwave Photonic Filters[J].LightwaveTechnologyogy,2011,29(12):1775-1782.
[4]Minasian Robert A.Photonic signal processing of mi-crowave signals[J].IEEE Trans Microw Theory Tech,2006,54(2):832-846.
[5]Erwin H,Chan W.Cascaded Multiple Infinite ImpulseResponse Optical Delay Line Signal Processor WithoutCoherent Interference[J].Lightwave Technology,2011,29(9):1401-1406.
[6]Joshi Himanshu,Sigmarrsson Hjalti H.High-QFullyReconfigurable Tunable Bandpass Filters[J].Trans-chions on microwave theory and techniques,2009,57(12):3525-3533.
[7]Zhu Kun,Ou Haiyan,Fu Hongyan,et al.A simpleand tunable single-bandpass microwave photonic filterof adjustable shape[J].IEEE Photon Technol Lett,2008,20(23):1917-1919.
[8]肖云,赵文义,朱坤,等.基于光纤环结构的微波光子滤波器[J].浙江大学学报(工学版),2009,6(43):1168-1171.
[9]王旭,梁晓东,聂奎营.级联MZI带通巴特沃斯微波光子滤波器的设计[J].光通信研究,2012,(5):46-49.