Target position and speed detection - is performed by transmission of two frequencies and measuring reflected signals

摘要

Position and speed of a target is determined from reflection of signal comprising two frequencies. Time difference between transmissions is known and processing of received signals enables noise and signal dispersion effects in transmission medium to be overcome. A signal comprising two frequencies is transmitted to a target. These signals have a known initial difference in time of transmission. Signals reflected from a target are separated and the time is determined from initial transmission for both frequencies to determined target velocity components using correlation techniques. Corrections are applied to each transit time for the two transmission frequencies to determined target distance.