基于梳状滤波器的FIR数字滤波器设计  

An FIR Digital Filter Design Based on Comb Filter

作　　者：叶波[1] 李天望[2] 江金光[2] 

机构地区：[1]上海电力学院计算机与信息工程学院微电子研究所,上海200090 [2]武汉大学集成电路与通讯软件系,武汉430079

出　　处：《半导体技术》2009年第10期1018-1021,共4页Semiconductor Technology

基　　金：国家科技部技术创新基金项目(07C26213101259)

摘　　要：根据子滤波器抽头级联法,采用梳状滤波器作为子滤波器,设计了一种新型FIR数字滤波器。通过C语言编程的方法来选择子滤波器阶数,使原型滤波器的过渡带宽度最宽。采用经过变换的通带和阻带边界频率来进行原型滤波器的设计,使得原型滤波器的阶数比传统实现方法低很多。采用该方法实现的FIR滤波器乘法器个数比传统方法少很多,硬件实现更为简单,大幅减小了硬件开销。该方法已成功用于回声消除和噪声抑制芯片,FIR滤波器的面积约为传统方法的50%,用180nm3.3V/1.8V6层金属混合信号CMOS工艺流片,结果表明,对于过渡带较窄的滤波器,该方法非常有效。Based on the tapped cascaded sub-filter, an FIR digital filter was proposed with the comb filter as the sub-filter. The order of the comb filter is calculated by a C language program, so that the prototype filter has the widest transition bandwidth. Using the transformed pass-band and stop-band edge frequency, the order of the prototype filter is less than that of the conventional design. Thus the number of multipliers in the new FIR filter can be greatly reduced, which simplifies hardware design and reduces the hardware overhead. The methodology is successfully used in an echo cancellation and noise suppression chip. The area of FIR filter is 50% of that the conventional design. The chip is fabricated in a 3.3 V/1.8 V 6- metal 180 nm mixed-signal CMOS process, and the results show that it is very efficient for the narrow transition band filter.

关 键 词：FIR数字滤波器 梳状滤波器 子滤波器抽头级联 

分 类 号：TN713.7[电子电信—电路与系统]