相位计

高精度数字相位计及其测试

赵海章 许 永 陈希辰

摘要

当今，相位的测量需求日益增长。高精度测距大多采用的是激光相位式测距。相位式测距是通过测量连续的幅度调制信号在待测距离上往返传播所产生的相位延迟，来间接的测定信号传播的时间，从而求得被测距离的。因此，信号相位测量的精度也就决定了测距的精度。

本文将介绍一种新型高精度数字相位计，它将可编程逻辑器件的高速度和高精度与单片机强大的控制和运算功能相结合，采用填充计数测量相位的原理设计出一种高精度相位计。为了对这一个设计进行测试，我们设计了一高精度相位差可调直接数字频率合成信号源作为被测对象。

从实验结果来看，这种相位计不仅精度高、稳定性好、实现方便、而且使相位测量变得简单方便，实现宽频率范围内的相位测量的设计，该设计在实际应用中获得理想效果。 从市场来看，测量交流电流，测量两电压之间、两电流之间及电压、电流之间的相位，在电力部门、工厂和矿山、石油化工、冶金系统等是理想仪表，具有广泛的市场前景。同档次的相位计市面上要买5000元以上，而此设计只要300~400元则可以做到。可见此设计市场潜力巨大，效益可观。

关键词：相位，相位测量，可编程逻辑器件，直接数字频率合成

A high precision digital phasic measure and its testing

Abstract

Moderm time, phasic measure demand increasingly. high precision distance measure mostly adopt is measure distance with laser phasic model. Measure distance with laser phasic model which is mesure phasic delay which sequence amplitude modulation signal spead out and home on the target distance,to indirect mensurate spread time,accordingly obtain distance.so ,precision of signal phasic measure decide the precision of measure distance.

This text introduce a new type high precision digital phasic measure,it plenty syncretize with the high precision and high rate of CPLD and the mightiness control and operation of MCU, designed a high precision phasic by the theory of fill counting measure phasic.For testing this design,we design a high precision changeable phasic difference DDFS signals source as measure object.

the experiment result show that this phasic measure not only has high precision, highly stability,realize easy,but also let phasic measure easily,realize width frequency phasic measure,this design work ideality in practice.

Seeing from market,measure AC current,measure phasic between two voltage, two current,voltage and current,it generally use in electric power,factory and mine,oid chemical plant,metallurgy system and so on is a ideality measure,having wide market foreground.The same level measure sale over 5000 yuan,but this design only need 300~400 yuan in produce.so ,it may