新型负系数微波光子带通滤波器设计

提出了一种基于偏振调制的负系数带通微波光子滤波器结构,克服了正抽头系数低通滤波的限制,并对所提结构的可行性进行了详细的理论分析和仿真实验验证.系统利用偏振调制器特殊的相位调制特性,通过控制抽头光信号的偏振态,实现了相位调制到强度调制的转换,实现了2抽头的正、负系数带通滤波器.调节PC2和PC3,当上下2路抽头光信号的偏振态方向满足θ1=π-θ2时,实现了负系数带通滤波器;当满足θ1=θ2时,实现的是正抽头的低通滤波器.

Novel Microwave Photonics Band-pass Filter Design with Negative Coefficiect

A novel tunable negative-tap band-pass photonic microwave filter using polarization modulation together with susceptible to polarization components is proposed for overcoming the restrictions that positive tap coefficients can only achieve the low pass filter.We carried on the detailed theoretical analysis and simulation experiments about the feasibility of this structure.The polarization modulator is a special phase modulation that the passed optical signal will suffer from orthogonal and reverse phase direction modulation.The phase modulated signal will change to the intensity modulation by adjust the polarization controllers PC2 and PC3which effect on the polarization of modulated optical signal.A negative coefficient tap microwave photonic band pass filter will be obtained when the polarization of two taps satisfy the expressionθ1=π-θ2,simultaneously,a positive coefficient tap microwave photonic low pass filter realized whenθ1=θ2.