一种基于状态机的毛刺信号滤波方法

A Filtering Method for Burr Signal Based on State Machine

提出并实践了一种状态机的实时滤波方法,并成功应用于某军用车辆速度检测.该方法以CPLD(FPGA)作为硬件,在高频时钟驱动下检测信号中瞬态脉冲宽度,滤除宽度短的脉冲,输出宽脉冲,从而实现脉冲干扰滤波功能.阐述了该方法的原理和状态机实现方法,分析了该方法的滤波特性,并通过仿真计算其在方波毛刺信号上的应用,论证了该方法的可行性以及滤波宽度变化对该方法精度的影响.

High frequency burr in the pulse signal is one of the most important reasons to effect the detection accuracy and reliability of signal.This paper presented and practiced a real-time filtering method of state machine,and successfully applied to some speed detection for military vehicle.The method,using CPLD as hardware and driven by high frequency clock,detects transient signal,filtered out the short pulse and output the wide pulse,so as to realize filtering.This paper introduced in detail the principle and implementation method of the state machine,and analyzed the filtering characteristic of this method.This paper validated its feasibility and influence of filtering width changes on precision by simulating its application on square signal burr.