基于多波长激光器和MZ干涉仪的可调谐可重构微波光子滤波器

A Tunable and Reconfigurable Microwave Photonic Filter Based on Multi-wavelength Laser and MZ Interferometer

提出了1种基于波长间隔可调谐多波长激光器和MZ干涉仪的微波光子滤波器.光子晶体光纤(PCF)Sagnac环滤波器具有波长选择的功能,使激光器产生多波长.向PCF的一个大空气孔中填充甘油,调节温度,改变PCF的双折射,能够使激光器产生不同波长间隔的激光.该激光器作为微波光子滤波器的光源,通过连续调节输出激光的波长间隔,可使滤波器具有不同的自由频谱范围(FSR),实现了滤波器的连续可调谐.当温度的变化范围为25-120℃时,仿真测得,FSR的变化范围为2.33-10.54 GHz.此外,通过调节MZ干涉仪两臂的臂长差,改变载波系数,使滤波器通带具有不同的主旁瓣抑制比和3 d B带宽,频率响应形状发生明显变化,实现了滤波器的可重构特性.

A tunable and reconfigurable microwave photonic filter based on multi-wavelength laser and MZ interferometer is presented. Photonic crystal fiber（PCF） of Sagnac loop filter has the function of wavelength selection to make the laser producing multiple wavelength. One of a big air hole of PCF filling with glycerin, adjusting temperature could change the birefringence of PCF, then the laser produces lasing with different wavelength space. Taking this laser as the light source of the microwave photonic filter, and continuality adjusting the wavelength spacing, the filter will obtain different free spectral range（FSR）, implementing the continuality tenability. When the temperature range is 25-120℃, the stimulated result shows that the FSR range is 2.33-10.54 GHz. In addition, by adjusting the arm length difference of two arms of MZ interferometer, it could change carrier coefficient. The filter will have different main to sidelobe suppression ratio and 3 dB bandwidth, the shape of the frequency response is changed obviously, implementing reconfiguration.