Spread spectrum technology-based laser radar ranging method and device

Abstract

The invention discloses a spread spectrum technology-based laser radar ranging method and device, and belongs to the field of laser radar ranging. The method comprises the following steps of S1, enabling bit information of a transmission sequence to carry out phase modulation on a light source signal by utilizing a phase difference between a pair of adjacent code elements; S2, enabling the phase-modulated light signal to enter a to-be-measured space through a transmission optical antenna; S3, enabling the reflected light signal to enter a delay interferometer so as to realize the demodulationof the light signal; S4, carrying out photoelectric conversion on the demodulated light signal through a photoelectric balance detector; and S5, enabling a local sequence to realize range measurementby utilizing at least one phase comparison manner of code chip phase comparison and code clock phase comparison. Based on a spread spectrum technology, the laser radar ranging method and device are strong in external interference resistance, long in detection distance and low in cost, and are capable of carrying out rough measurement or accurate measurement according to practical requirements so as to improve the measurement speed.

Description

technical field [0001] The invention relates to the field of laser radar distance measurement, in particular to a laser radar distance measurement method based on spread spectrum technology. [0002] The invention relates to the field of laser radar distance measurement, in particular to a laser radar distance measurement device based on spread spectrum technology. Background technique [0003] As a sensor that can obtain information about the position and shape of objects, lidar is suitable for terrain mapping. It is often used in indoor modeling, data collection of roads and facilities, mine goaf measurement, or carried on aircraft for large-scale power line inspection, forestry census, water conservancy survey, etc., and has a wide range of applications. At present, the application of lidar measurement technology is showing a diversified trend. In addition to traditional surveying and mapping, it has shown broad market prospects in emerging industries such as unmanned dr...

AI Technical Summary

Problems solved by technology

The main disadvantages of FMCW are: firstly, the FMCW laser source is bulky and expensive, and secondly, it requires more computing power, so it is slower in generating a full 3D surround map, and the measurement accuracy is very critical to the degree of linearity in modulation. sensitive

The difference in beam diameter will lead to completely different phase modulation methods. For example, it is very easy to select a device with a half-wave voltage of a few volts for a fiber phase modulator. If the phase modulation is performed on a beam whose beam diameter reaches centimeters, the half-wave voltage will Dozens of times or even hundreds of thousands of times increase, which will make the modulation method used in the optical fiber phase modulator unchanged, and in some cases it is difficult to use it in the laser radar

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