Patent ID: 6738313
Filing Date: 2004-05-18
Classification: G01S

Abstract:
A system for detecting the distance from an obstacle, and comprising:at least one transducer for transmitting a transmission signal in a direction of the obstacle, and for receiving an echo signal corresponding to a reflection of the transmission signal off the obstacle; a chaos generator for driving said at least one transducer with a chaotic signal so that the transmission signal has characteristics of the chaotic signal; a pulse generator connected between said chaos generator and said at least one transducer, said pulse generator being driven according to a pulse position modulation scheme so that a time interval that elapses between generation of two consecutive pulses by said pulse generator has characteristics of the chaotic signal; and a driving circuit connected between said pulse generator and said at least one transducer, said driving circuit comprising a signal source for producing the transmission signal as a square-wave signal having a varying frequency with at least one first frequency and at least one second frequency, the at least one first and second frequencies being different from one another, and said signal source being driven by said pulse generator so that said signal source modifies a frequency of the transmission signal according to the chaotic signal.