Patent ID: 6232911
Filing Date: 2001-05-15
Classification: G01S

Abstract:
Device for distance measurement by radar, comprising:(a) a distance measuring device having a frequency modulated radar-transmitter and -receiver (10) for guiding a radar beam onto an object to be measured and reflecting said beam from the object and for mixing of a transmitted frequency with a received frequency, a beat signal (30) generated by mixing the transmitted and received frequencies,(b) frequency modulator connected to the radar-transmitter and -receiver for periodically varying the transmitted frequency of the radar signal of the radar-transmitter and -receiver as a saw tooth function and wherein the frequency of the beat signal corresponds to a travel time of the radar beam reflected by the object to indicate a measure of a distance of the object and(c) a signal processing circuit connected to the modulator generating a measured value corresponding to the distance of the object and,(d) a phase control circuit (phase locked loop circuit) (66) connected to the modulator for feeding the beat signal and for providing an output frequency, the output frequency forming the measured value of the distance,further comprising a frequency voltage converter connected to the phase control circuit, wherein the output frequency of the phase control circuit (66) is fed into the frequency voltage converter (90) which supplies an output voltage which is proportional to the beat frequency and represents the measured value for the distance.