摘要:
In a process and with a device for non-contact measurement of speed on surfaces, in particular for ski speed measurement on snow surfaces, a signal (102) with a fixed frequency is beamed in the direction of travel (106) at a beam angle ( alpha ) which is less than a half aperture angle ( THETA /2) of the device (100) emitting the signal (102); a signal (110) reflected at the surface (104) and Doppler-shifted relative to the beamed signal (102) is received; from the Doppler spectrum of the received signal (110) that portion with the highest frequency and an energy value above a predetermined level is determined, and the speed is derived from the frequency of the determined portion of the spectrum.
摘要:
In a process and with a device for non-contact measurement of speed on surfaces, in particular for ski speed measurement on snow surfaces, a signal (102) with a fixed frequency is beamed in the direction of travel (106) at a beam angle ( alpha ) which is less than a half aperture angle ( THETA /2) of the device (100) emitting the signal (102); a signal (110) reflected at the surface (104) and Doppler-shifted relative to the beamed signal (102) is received; from the Doppler spectrum of the received signal (110) that portion with the highest frequency and an energy value above a predetermined level is determined, and the speed is derived from the frequency of the determined portion of the spectrum.
摘要:
In a process and with a device for non-contact measurement of speed on surfaces, in particular for ski speed measurement on snow surfaces, a signal (102) with a fixed frequency is beamed in the direction of travel (106) at a beam angle (α) which is less than a half aperture angle (Υ/2) of the device (100) emitting the signal (102); a signal (110) reflected at the surface (104) and Doppler-shifted relative to the beamed signal (102) is received; from the Doppler spectrum of the received signal (110) that portion with the highest frequency and an energy value above a predetermined level is determined, and the speed is derived from the frequency of the determined portion of the spectrum.