Determining instantaneous position and velocity vector of object - using frequency shift and time lapse between transmitted reflected radar signal

摘要

The frequency change of the received reflected signal is used to determine a velocity component of the object in the direction of the point (R) whilst the object distance is determined from the time lapse between transmission and reception. In computing this distance (k), account is taken of the effect on the time lapse (tt) due to vectorial addition in longitudinal direction or use is made of the formulae k = (c + v1)tt or k = (c -v1)tt in which c = velocity of light in vacuum and v1 = object velocity. This may be combined with transmission by the object of a signal with known frequency and, on reception at (R), determining the frequency and/or time lapse taking account of the differences in characteristics between the reflected and the emitted signals.