METHOD AND SYSTEM FOR ESTIMATING A PATH LENGTH DIFFERENCE OF A TARGET SIGNAL TRANSMITTED BY A SPACECRAFT OR AIRCRAFT

摘要

The present invention relates to a method (50) for estimating a path length difference between two paths followed by a target signal transmitted by a spacecraft or aircraft (21) in order to arrive at a first receiving antenna (32a) and a second receiving antenna (32b) of a receiving base respectively. The method (50) comprises a step (500) of measuring a useful phase difference between signals that correspond to the target signal received by the first receiving antenna (32a) and second receiving antenna (32b) and a step (502) of estimating the path length difference in accordance with the useful phase difference measurements. In addition the step (500) of measuring the useful phase difference comprises either correlating the signals received by the first receiving antenna (32a) and second receiving antenna (32b) respectively with a reference target signal or analysing said signals received by the first receiving antenna (32a) and second receiving antenna (32b) respectively using an FFT or a PLL. The present invention also relates to a system (30) for estimating path length differences.