Patent ID: 7548060

Claim:
A magnetic sensor system, comprising: magnetoresistive XMR sensor elements ( 5 , 6 ) that are sensitive to magnetic fields, electrical properties of said sensor elements being modifiable according to a magnetic field that can be influenced by a mobile, passive transmitter element ( 8 ), wherein the magnetic sensor system ( 1 ) has the two magnetoresistive XMR sensor elements ( 5 , 6 ) in a gradiometer system, each of which is assigned to one of two permanent magnets ( 2 , 3 ) having a predetermined separation (a) so that a homogenous magnetic field does not induce a bridge signal of a measuring bridge of a magnetic field of the gradiometer system, while a variation of the magnetic field produces a bridge signal; and wherein in terms of dimensions, separation and position relative to the magnetoresistive XMR sensor elements ( 5 , 6 ), the permanent magnets ( 2 , 3 ) are located such that an offset of the output signal of the sensor elements ( 5 , 6 ) in the gradiometer system is minimized, wherein the two magnetoresistive XMR sensor elements are positioned symmetrically to a central axis between the two permanent magnets.