Patent ID: 6501418
Filing Date: 2002-12-31
Classification: G01S

Abstract:
A method of automatically determining a ratio between the frequency of an output signal from a vehicle speed sensor and the vehicle's speed using a police Doppler traffic radar coupled to said vehicle speed sensor, comprising the steps:a) reading at least one signal frequency output from a vehicle speed sensor to a police Doppler traffic radar, and obtaining from the police Doppler traffic radar what the traffic radar computes is the correct ground speed calculated from the reflected signal from a stationary object at the time the signal frequency from said vehicle speed sensor is read; b) repeating the process of step a) multiple times and storing the data; c) automatically determining the reliability of the ratio without any input from a human being needed by evaluating over time one or more factors which are indicative that said police Doppler traffic radar has locked onto and is tracking the correct ground speed including at least persistence of the same ratio for a plurality of different ground speeds obtained from said police Doppler traffic radar.