Dual-frequency sweep frequency laser ranging device and method

Abstract

The invention discloses a dual-frequency sweep frequency laser ranging device and method. The device comprises a wide-spectrum pulse light source, a pulse modulation module, a dispersion stretching module, a measuring arm, a reference arm, a precision coherent detection module, a flight time measurement module and a control terminal. The pulse modulation module and the dispersion stretching module are respectively used for performing frequency multiplication processing, frequency division processing and dispersion time domain stretching on coherent wide-spectrum mode-locked pulse light generated by the wide-spectrum pulse light source to obtain a first sweep frequency signal and a second sweep frequency signal; the precision coherent detection unit is used for collecting interference signals of the first sweep frequency signal and the second sweep frequency signal; the flight time measurement module is used for collecting a second sweep frequency signal before the measurement arm is input and a second sweep frequency signal output by the measurement arm; and the control terminal is used for determining a to-be-measured distance. The ranging device can be used for measuring a blind area, so that the detection range is enlarged to more than tens of kilometers, and high-speed, high-precision and wide-range sweep frequency interference laser distance measurement is realized. 本发明公开了一种双重频扫频激光测距装置及方法，包括：宽谱脉冲光源、脉冲调制模块、色散拉伸模块、测量臂、参考臂、精度相干探测模块、飞行时间测量模块以及控制终端；脉冲调制模块和色散拉伸模块分别用于对宽谱脉冲光源产生的相干宽谱锁模脉冲光进行倍频处理、分频处理以及色散时域拉伸，得到第一扫频信号和第二扫频信号；精度相干探测单元用于采集第一扫频信号和第二扫频信号的干涉信号；飞行时间测量模块用于采集输入测量臂前的第二扫频信号和测量臂输出的第二扫频信号；控制终端用于确定待测距离。本发明的测距装置可以测量盲区，使探测范围提高到数十千米以上，实现高速、高精度和大量程的扫频干涉激光测距。