数字接收机中合成滤波器的设计与性能分析

在宽带／窄带兼容的数字接收机中，匹配滤波器一般需要前置级联积分梳状（CIC）滤波器。在高性能要求的系统中，还需要对CIC进行补偿。传统的方法是将CIC补偿滤波器和匹配滤波器分开设计，而本文提出了一种将两者合并，使用一个滤波器来实现两种功能的方法。在不增加滤波器阶数的情况下，这种方法可以得到更好的滤波器性能，同时又节约了硬件资源。

Design and Performance Analysis of Composite Filter in Digital Receiver

In a narrowband/wideband compatible digital receiver,a CIC filter located before the match filter is preferred.In a high performance system,a FIR filter to reduce the CIC filter''s droop in pass-band is also necessary.The CIC compensation filter and the match filter are designed separately in a traditional digital receiver,while in this paper FIR design method is developed which combines the frequency responses of CIC compensation filter and match filter together.With the same length of FIR taps,the composite filter has a better performance than the separated design.On the other hand,only half the number of taps of the separated method is needed in a composite filter to obtain the same performance.