基于频率响应掩蔽法的宽带滤波器的设计

针对FIR滤波器设计中锐截止宽带滤波器阶数较高、计算复杂的问题,提出用频率掩蔽法,先设计一个过渡带为目标过渡带的L倍的原型滤波器,其实现复杂度远小于所要求的滤波器,依据L倍内插滤波器的过渡带宽是原型滤波器的1/L的原理,利用一对互补滤波器和掩蔽滤波器,得到了较低计算复杂度的锐截止宽带滤波器。

Design of Wideband Filters by Frequency Response Masking Approach

This article puts forward the frequency response masking approach in order to solve the problem about the design of sharp cutoff filters with high order and computational complexity.We first design a prototype filter which transition bandwidth four times larger than the one needed,the implementation complexity of this prototype filter is much smaller than the filter we required.Basing on the fact that an interpolated filter has a transition band L times smaller than the prototype filter,using a pair of complementary filter and a masking filter,one can generate large bandwidth sharp cutoff with low implementation complexity.