中文摘要：

为了提高相位式激光测距的精度，提出以马赫增德尔调制器作为外调制器，提高调制频率以提高测距分辨率。介绍了射频相位式激光测距试验装置的组成，该系统以小数分频锁相环产生1.5 GHz左右正弦调制信号，采用马赫增德尔调制器对光波进行强度调制，并以差分式测量的方法抵消温度引起的相位差漂移，将信号下变频后按相关法计算相位差。试验表明，由光电探测器噪声和电路噪声引起的相位差漂移小于0.15°，该测距装置的测距误差在±0.05 mm以内。

英文摘要：

In order to improve the performance of laser phase-shift range finder, a Mach-Zehnder modulator is used as external modulator of the range finder, and the modulation frequency is increased to obtain high distance resolution. A phase-shift ranging system is described. In the system, the sinusoidal modulation signals about 1.5 GHz is generated by a fractional-N frequency synthesizer, and the Mach-Zehnder modulator working as an intensity modulator is used. The phase difference drift caused by temperature is eliminated with differential measurement method, and the phase-shift is obtained with a heterodyne technique associated with cross-correlation analysis. The experimental results show that the phase difference drift caused by the photoelectric detector and circuit noise is less than 0.15°, and the distance error of the ranging device is within ±0.05 mm .