一种锐化的高速CIC抽取滤波器

将余弦滤波器和锐化技术应用到CIC抽取滤波器中，提出一种高速高效的CIC滤波器设计方法。首先，将抽取滤波器分解为两部分，工作在高速端的部分作解递归处理，另一部分作部分锐化处理。然后，对非递归部分用余弦滤波器预滤波，并按照抽取等效变换规则，实行分解置换，使各单元的工作速度逐级降低。最后，把多相滤波技术应用到非递归部分的各单元，进一步降低其工作速度。仿真结果证明，改进的CIC抽取滤波器频率响应特性得到显著改善，滤波器工作速度大大降低。

High Speed Sharpening of CIC Decimation Filter

Cascade Integrator Comb (CIC) decimation filter is attractive due to no multipliers needed, but the response and speed of conventional CIC filter do not satisfy the performance requirement. To improve the filter performance, a high speed and efficient CIC decimation filter is proposed in this paper. The decimation filter is decomposed into two sections. Non-recursive form is deduced for the front section, and exchange rule and polyphase decomposition technique are applied. These measures make the front section work at lower data rate and compute efficiently. Sharpening technique and cosine prefilter are applied to the other section, which enhances the response of the filter greatly. Simulation results demonstrate that the frequency response and speed of proposed CIC decimation filter are improved evidently.