Patent ID: 6701783
Filing Date: 2004-03-09
Classification: G01F

Abstract:
A process for determining a position of at least one border area between different mediums with the aid of electromagnetic waves, comprising:emitting a departing wave from a wave transmitter, said emitted wave having at least one propagation speed component that is parallel to normal line(s) of the border area of the different mediums; reflecting the emitted departing wave, at least partially, on at least one border area; receiving portions of the reflected returning wave by a wave receiver; determining travel times between emission of the departing wave and reception of the returning wave; determining a position of at least one border area from the travel times, based on different propagation speeds of the waves in the different mediums, whereinthe portions of the reflected returning wave are employed to determine the different propagation speeds (v) in the different mediums (4, 5), the different propagation speeds (v) in the different mediums (4, 5) are determined from the amplitude ratios (r) of the departing wave (UH1) to the returning wave (UR1) and a quadratic relationship of dielectric constants &egr;r to the amplitude ratios (r)(=reflection factor).