中文摘要：

锯齿形光谱（JAWS）滤波器的光谱成分比较复杂，是一种较难实现的光谱滤波器。本文通过数值仿真对基于虚像相位阵列（VIPA）的JAWS滤波器的主要参数如线性度、占空比和信噪比（SNR）等进行了优化，并进行了实验验证；通过对JAWS滤波器插损的分析，将反射式的工作方式改变为透射式的工作方式，使整个滤波器的附加损耗从20dB减小到小于6dB；同时，滤波器的性能也有了明显的进步。

英文摘要：

Jammed-array wideband sawtooth （JAWS） filter has periodic multi-channel sawtooth spec- trum. Due to the complex spectral components, it＇s difficult to make a passive multi-channel sawtooth fil- ter. In this article,we present a modified JAWS filter with low loss. It only consists of four elements,in- eluding a fiber collimator, two lenses and a virtually-imaged phased array （VIPA）. The beam transmitted through the VIPA is collected by a lens and a large area photodetector rather than a mirror is used to re- flect the beam back into the fiber. The extra insertion loss is lower than 6 dB and the performance of the filter is much better than that of the JAWS filter with beam reflected by a mirror. The main characteris- tics of the jammed-array wideband sawtooth filter based on a virtually-imaged phased array are studied systematically. The main parameters, such as linearity, duty cycle and signal-to-noise ratio,are optimized by numerical simulation and tested by the experiment. Since the free spectrum range of the filter is decid- ed by the thickness of VIPA,the optimization of VIPA with different thicknesses is also discussed. The filter might be used in fast sensitive interrogation of concatenated multi-channel fiber Bragg grating sen- sors and ultra-high-frequency electrical sawtooth waveform generation.