Laser detection system and method for pulse emission coherent reception

Abstract

The invention relates to the field of detectors, and especially relates to a laser detection system and method for pulse emission coherent reception. The laser detection system comprises a laser seedsource, a beam splitter, a delay optical fiber, an optical receiving assembly, a scanner, a frequency mixer, a signal processing assembly and a main control unit. According to the pulse emission coherent reception laser detection system and method, a pulse signal with bias is set, and a coherent receiving mode is combined, so that direct pulse distance measurement and a coherent receiving system are combined, and the advantages of high coherent receiving sensitivity and high external interference resistance are utilized; the minimum detectable distance is effectively reduced, expensive modulation devices in an existing coherent detection system are avoided, and the system cost is effectively reduced; and meanwhile, the pulse power of the emitted laser can be effectively reduced in a pulseemission coherent receiving mode, continuous emission of the continuously modulated laser is not needed, the average laser power of the system is effectively reduced, and the power consumption of thesystem is further reduced.

Description

technical field [0001] The invention relates to the field of detectors, in particular to a laser detection system and detection method for pulse emission and coherent reception. Background technique [0002] Lidar is a radar system that emits laser beams to detect characteristic quantities such as the position and speed of targets. At present, common laser detection can be divided into direct detection and coherent detection according to different detection methods. [0003] There are two main types of direct detection schemes. One is to emit one or several laser pulse signals during the working process. When these emitted pulses irradiate the target, a part of the energy will be reflected and received by the detection system. The time difference between receiving moments is used to realize distance detection, and the other is to transmit an amplitude-modulated continuous sine / cosine modulation signal or square wave modulation signal. The receiving system receives the energy...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to provide a laser detection system and detection method for pulse emission and coherent reception in view of the above-mentioned defects of the prior art, which overcomes the limited responsivity of the direct detection system in the prior art and is easily disturbed by external noise And the defects that require higher laser emission energy, as well as the defects that the coherent detection system in the prior art requires expensive modulation devices and complex algorithms for signal analysis

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