Weber, N.N.WeberLueftner, H.H.LueftnerSeitzer, D.D.Seitzer2022-03-082022-03-082000https://publica.fraunhofer.de/handle/publica/304582In a process and a device for contactless velocity measurement on surfaces, in particular the measurement of ski speed on snow surfaces, a signal at a fixed frequency is emitted in the direction of travel below a radiation angle, whereby the radiation angle is smaller than half the aperture of a device emitting the signal: a signal reflected by the surface is received, said signal being subjected to a Doppler shift in relation to the emitted signal; the spectral component with the highest frequency from the Doppler spectrum of the received signal and which exceeds a specific energy value is detected; and the speed is derived from the frequency of the detected spectrum component.de608patent1995-19501228