Monitoring device based on single-photon avalanche detector line-scan digital camera and speed measurement method

Abstract

The invention provides a speed measurement device and method based on a single-photon avalanche detector line-scan digital camera. A single-photon avalanche detector is used as an imaging device to form a linear array camera for speed measurement, and the speed of a moving object is calculated by utilizing the known size of the object, the number of longitudinal pixels corresponding to the objectin an image, the camera single-row shooting integral time and the camera shooting angle. Each unit of the single-photon avalanche detector linear array comprises a single-photon avalanche detector, aquenching and resetting circuit, a counter and a register, wherein the output end of the single-photon avalanche detector is sequentially connected with the quenching and resetting circuit and the counter, and the output end of the counter is connected with the register; and the single-photon avalanche detector adopts a single-photon avalanche diode. The device and the method provided by the invention have the remarkable advantages that speed measurement can be realized in daytime with strong illumination, night with weak light and an extremely dark environment, and the speed measurement is more accurate.

Description

technical field [0001] The invention relates to a speed measuring device and method for a moving target, in particular to a speed measuring method using imaging technology. Background technique [0002] At present, the main speed measurement technologies for moving targets include microwave radar monitoring technology, laser detection technology, ground sensing coil speed measurement and video speed measurement, etc. [0003] Microwave radar monitoring technology mainly uses the Doppler Effect principle: when the target approaches the radar antenna, the frequency of the reflected signal will be higher than that of the transmitter; conversely, when the target moves away from the antenna, the frequency of the reflected signal will be lower. on the transmission probability. In this way, the relative speed between the target and the radar can be calculated by changing the value of the frequency. However, the reception and emission of electromagnetic waves by this technology are...

AI Technical Summary

Problems solved by technology

Ground induction coil speed measurement requires the coil to be installed underground, which will damage the road surface during construction, and is easily deformed by the environment, and the actual maintenance cost is relatively high

[0005] Video speed measurement is based on imaging means, and then uses image processing to achieve speed measurement, but the video speed measurement method is limited by external conditions such as lighting, and the amount of video data is large, which is not conducive to real-time data processing

[0006] The existing linear array camera speed measurement system generally uses ordinary CCD or CMOS linear array as the imaging device to measure the speed, but the ordinary CCD or CMOS uses A / D conversion to read data, which is affected by the analog-to-digital converter (ADC) and The full well of the device is limited, and its dynamic range of light intensity is very limited. It is necessary to change the camera sensitivity or change the exposure time to achieve imaging of different ambient light intensities. When the ambient light intensity changes very quickly, CCD and CMOS may be sensitive to If the speed change is not timely, the phenomenon of data loss will occur

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