Laser radar measurement method and laser radar system

Abstract

The invention provides a laser radar measurement method and a laser radar system. The laser radar measurement method comprises the steps of generating an output optical signal with a tunable wavelength through a tunable laser generation unit; performing linear frequency modulation on the output optical signal to obtain a frequency-modulated continuous wave signal; splitting the frequency-modulated continuous wave signal to obtain an emergent light signal and a local oscillation light signal; carrying out power amplification on the emergent light signal and then emitting the emergent light signal by an optical phased array emission unit, and carrying out two-dimensional scanning on a target object; and receiving an echo light signal reflected by the target object, and obtaining distance and / or speed information of the target object according to the echo light signal and the local oscillation light signal. Tunable laser and an optical phased array system are combined, two-dimensional scanning is achieved on the basis of a one-dimensional optical phased array device, and the situation that the one-dimensional optical phased array device achieves two-dimensional scanning in a stacking mode is avoided; by adopting an external modulation mode, the optical phased array and the broadband tunable laser are reasonably combined with a frequency modulation continuous wave system, and the defect that narrowband linear frequency modulation of the broadband tunable laser is difficult is overcome.

Description

technical field [0001] The invention relates to the technical field of laser radar, in particular to a laser radar measurement method and a laser radar system. Background technique [0002] Optical phased array (Optical Phased Array, OPA) can realize scanning at any emission angle, and there are no mechanical rotating parts, so it is considered to be one of the most competitive core devices in solid-state lidar. [0003] At present, the research on OPA devices is very hot, but it is still difficult to design and process the two-dimensional scanning OPA devices based on pure phase control, and it is still difficult to be widely used at this stage. On the other hand, the one-dimensional scanning OPA device can fully accept wavelength modulation to realize two-dimensional scanning according to its working principle. Frequency Modulated Continuous Wave (FMCW) technology is very suitable for application in lidar systems due to its inherent ranging and speed measuring mechanism, ...

AI Technical Summary

Problems solved by technology

[0004] In the prior art, the FMCW mechanism is implemented on the one-dimensional OPA, usually the two-dimensional scanning of the one-dimensional OPA cannot be realized through wavelength modulation, and the two-dimensional scanning can only be realized through the stacking of the one-dimensional OPA; in addition, the FMCW mechanism is realized on the one-dimensional OPA The dynamic range and precision requirements of the laser are relatively high

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