自动线性跟踪Butterworth有源滤波器研究

滤波是通信、测试、数据采集和实时控制等领域至关重要的环节。通常的模拟滤波器，由于截止频率固定，在某些宽频率动态范围且有实时性要求的应用场合，往往达不到预期的滤波效果，有时甚至影响整个系统的正常运行。本文从有源滤波器的机理分析入手，提出了一种由单片机参与的滤波系统，它能自动跟踪输入信号频率，线性地选择合适的滤波器截止频率，弥补了原有滤波器的不足。

A Study on the Automatic-lincar-following Butterworth Active Filter

Filtering is extremely important in communication,measurement, data acquisition and real time control fields. The general analogue filter will not obtain expectiveaim in some real - time situations of wide frequency dynamic range because its cut-off frequency is fixed, sometimes it will even effect the runing of system.This paper analyzes filter for principle, puts forward a controllable filtering system based on single computer. It will follow frequency of input - signal automatically and select suitable cut - off frequency of filter linearly. It counteracts the weakness of the former filter.