Vehicle type classification method based on single frequency continuous-wave radar

Abstract

The vehicle classification method includes: the time-domain radar signal of single-frequency continuous wave radar is used as input to conduct time-frequency analysis to obtain a radar echo Doppler frequency spectrum chart changing along time; by Hafford counterchange the Doppler chart is mapped into a scattered central position parameter image; through characteristic picking-up, Karhunen-Loeve(K-L) screening and compressing, a characteristic sample is obtained, which is classified using Fisher rule to obtain the vehicle-type classification. For multi-type condition, multiple two-type classifiers are used to conduct respectively pairwise classification, according to the result of the classifiers said above the classification result is obtained by voting. Advantage: simple and reliable structure and low cost, conducting classification synchronously with detecting and speed-measuring of vehicles.

Description

technical field [0001] The single-frequency continuous wave radar adopts the working method of continuously transmitting microwave signals, and uses a zero-IF receiver to directly mix the local oscillator signal and the received signal to obtain the Doppler signal. The invention relates to using a single-frequency continuous wave radar to detect and measure speeds of vehicles on the road while classifying vehicle types, and belongs to the field of intelligent traffic vehicle detection. Background technique [0002] Aiming at the problem that the current vehicle detection radar can only measure the distance and speed of the vehicle but cannot classify the vehicle type in detail, the invention proposes a method for classifying the vehicle type using the vehicle Doppler information provided by the low-cost single-frequency continuous wave radar. [0003] The following articles and patent documents basically cover the main background technologies in this field. In order to expl...

AI Technical Summary

Problems solved by technology

Disadvantages The radar is installed perpendicular to the ground, and the radar beam is perpendicular to the moving direction of the vehicle target, so the speed of the vehicle cannot be measured using Doppler information; secondly, an accurate vehicle profile must be obtained from the above measurement results (height versus time diagram) information, the speed of the vehicle must be known, and the uncertainty of the vehicle speed will bring certain ambiguity to the identification of the vehicle type; finally, this scheme usually uses a wideband pulse radar, which has a relatively complicated structure and high cost, which brings certain difficulties to the promotion of this technology. difficulty

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