A method and device for acquiring radial velocity based on automotive blind-filling radar

Abstract

The invention provides a radial speed acquisition method and a radial speed acquisition device based on vehicle close-proximity radar. The method comprises the following steps: after acquiring a rising edge intermediate-frequency receiving signal and a falling edge intermediate-frequency receiving signal of a triangular wave signal of vehicle close-proximity radar, respectively acquiring a rising edge spectrum signal corresponding to the rising edge intermediate-frequency receiving signal and a falling edge spectrum signal corresponding to the falling edge intermediate-frequency receiving signal; after mirroring the falling edge spectrum signal, calculating the correlation degree between the rising edge spectrum signal and the mirrored falling edge spectrum signal when knowing that the rising edge spectrum signal and the mirrored falling edge spectrum signal have matching peak serial numbers; and carrying out zero-padding inverse fast Fourier transform on a time-domain signal of the correlation degree to get a frequency-domain up-sampling signal of the correlation degree, acquiring the maximum serial number of the sampling signal, and acquiring the radial speed of a target vehicle according to the parameters and the wavelength and radar pulse repetition frequency of a preset radar triangular wave signal. The amount of calculation can be reduced under the condition of satisfying the calculation precision.

Description

technical field [0001] The invention relates to the technical field of automobiles, in particular to a radial velocity acquisition method and device based on an automobile blind-filling radar. Background technique [0002] Car blind-filling radar is an active safety configuration for cars, which can significantly reduce traffic accidents caused by blind spots in car rearview mirrors. Accurate measurement of the radial velocity of the target is an important parameter to distinguish the target from the stationary background and the velocity change of the same target at different times. Automotive blind-filling radar systems generally transmit triangular wave modulation signals, down-convert the rising and falling edges, discretely sample and perform Fourier transform to the spectrum, and measure the distance and radial velocity of the target by detecting the peak position of the spectrum. [0003] Such as figure 1 As shown, assume that the distance of the target vehicle is R...

AI Technical Summary

Problems solved by technology

[0009] At present, when calculating the radial velocity of the target vehicle according to formula (1), it is necessary to up-sample the peak signal of the rising edge spectrum and the peak signal of the falling edge spectrum respectively, and then calculate k up -k down , therefore, two upsampling is required, and the amount of calculation is large, but if no upsampling is performed, there will be spectrum leakage and fence effect, k up and k down Both are integers, and the radial velocity analysis accuracy of the target vehicle obtained by direct spectrum analysis is not greater than Corresponding to 11.25km / h, far from meeting application requirements

Images