Remote laser distance measuring system based on high-speed pseudo-random code modulation and photon counting

Abstract

The invention provides a remote laser distance measuring system based on high-speed pseudo-random code modulation and photon counting. A basic principle is as follows: a high-speed pseudo-random code is used for modulating continuous optical fiber laser; modulated signal light is emitted through a transmitter-telescope system; and target reflection light is received by the transmitter-telescope system and enters a single-photon detector. A photon counting card is used for carrying out pulse identification and threshold value judgment on a signal output by the detector to obtain an echo code element sequence; and distance information is obtained by carrying out related calculation on an original pseudo-random code sequence. The remote laser distance measuring system has the characteristics of realizing high repetition frequency and high precision remote laser distance measurement.

Description

technical field [0001] The invention relates to laser radar, which is a long-distance laser ranging system based on high-speed pseudo-random code modulation and photon counting. Background technique [0002] At present, the commonly used laser ranging methods mainly include time-of-flight pulse direct ranging method and phase measurement method. The pulse direct ranging method based on time-of-flight is the most widely used. The ranging principle is to obtain distance information by measuring the time interval between the transmitter and the measurement point. This method is simple to implement, but the ranging accuracy is low. When this method is used for long-range laser ranging, high peak power, narrow-pulse solid-state lasers and large-aperture receiving telescopes are usually used. The laser works at high peak power and high energy for a long time, which will reduce the stability of the system and increase the volume and power consumption of the system. In order to a...

AI Technical Summary

Problems solved by technology

The laser works at high peak power and high energy for a long time, which will reduce the stability of the system and increase the size and power consumption of the system

In order to avoid distance ambiguity, the system can only work at low repetition frequency, resulting in sparse measurement points and low distance resolution.

Compared with the direct distance measurement method, the phase measurement method has a complex structure and higher requirements for the coherence of the laser light source. It is suitable for short-distance and high-precision measurement occasions, and is not suitable for long-distance distance measurement.

At present, the pulse direct ranging method is mostly used in remote ranging and 3D imaging systems. Under the high peak power and low repetition frequency working mode, the distance resolution and ranging accuracy are low, which cannot meet the requirements of high-precision laser ranging and mapping. requirements

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