Patent ID: 6392607
Filing Date: 2002-05-21
Classification: B60R,G07C,H01Q

Abstract:
Antenna system for an anti-theft system of a motor vehicle, comprising:a. at least one primary coil which produces a magnetic field by which a query signal controlled by a control unit is transmitted to a code sender and thereupon a response signal is received from the code sender, b. a magnetic coupling element which is disposed in the vicinity of the primary coil and which is coupled magnetically therewith, whereby the signals are inductively transferred from the primary coil to the coupling element and vice versa, and by c. at least one secondary coil disposed at a distance from the primary coil which is connected by a conductor to the coupling element and which produces an additional magnetic field through which the query signal is also transmitted to the code sender and thereupon the response signal is received from the code sender.