数字式混频器

在红外激光测距中，一般是通过测量发射连续激光脉冲和被测目标回波信号的相位差而求得被测距离的。为了得到高测距精度，常把两信号分别同基准信号混频得到两个抵频信号再进行检相。传统的频率变换方法是利用晶体管的非线性来实现的，我们在研究JMX－1型精密激光测距仅中，采用数字集成电路，做成了数字式混频器，并取得高的测量精度。

Digital Mixer

We obtain the distance by measuring the difference of the phase between the continuous laser signal transmitted and the signal reflected by the object in the infrared rays distance measure.To obtain high precision,the method wixing the two signals with a basic standard signal to get two low frequency signals before phase measure is often implemented We adopt digital mixer consists of digital ICs in the JMX-1 precise laser distance metre and present high precision,in contras to the conventional frequency conversion which relies on the nonlinearity of transistors.