High precision speed-measuring distance-measuring radar system and method

Abstract

The invention relates to a high precision speed and distance measuring laser radar system and a speed and distance measuring method. The basic principle of the invention is as follows: linear chirp modulation and pseudo-random code modulation of lasers are performed; most lasers after modulation are taken as outgoing lasers and transmitted by a telescope; a small part of the lasers is taken as local oscillator beams and used for coherent detection; laser echo signals are divided into two parts; distance information is obtained after related operation of one part of the laser echo signals and original pseudo-random codes; the frequency difference of the local oscillator beams and echo signal beams is obtained after coherent detection of the other part of the laser echo signals and the local oscillator beams and pulse compression, and simultaneously comprises the distance information and Doppler shift; the Doppler shift is obtained through mathematical manipulation, thereby speed information is obtained. The high precision speed and distance measuring laser radar system and a speed and distance measuring method of the invention is characterized in that the speed information and the distance information of a target can be obtained with high precision.

Description

Technical field [0001] The patent of the invention relates to lidar, especially a high-precision speed and distance measurement lidar system and speed and distance measurement method. It is a system that combines pseudo-random code modulation technology, photon counting technology, coherent detection technology and pulse compression technology. , The speed and distance information of the target can be obtained with high precision. Background technique [0002] The aircraft needs to know its own speed and position information accurately when landing. This is critical for a safe landing. Especially for landing surfaces with significant discontinuities, such as the moon. The commonly used method is to measure the distance and then differentiate the distance to get the speed, because the discontinuity of the distance can not get the correct speed information. However, the method of cutting the echo signal into multiple small time periods, measuring the Doppler frequency shift of each...

AI Technical Summary

Problems solved by technology

The commonly used method is to measure the distance and then differentiate the distance to obtain the speed, because the discontinuity of the distance cannot obtain the correct speed information

However, the method of cutting the echo signal into multiple small time periods, measuring the Doppler frequency shift of each time period to obtain the speed information, and then calculating the distance information according to the time corresponding to the time period cannot obtain high resolution. rate distance information

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