Patent ID: 7511483

Claim:
A device for sensing an RF field, the device comprising a flux-receiving loop including a circumferential path having a defined path width (d), said flux-receiving loop having a portion that transforms a magnetic flux flowing through the flux receiving loop into a high magnetic field, wherein said portion comprises a constriction of the flux-receiving loop that concentrates current lines in the circumferential path to define a current-field transformer, and at least one very low noise magnetic field transducer which is located at a very close distance from said constriction, wherein the flux-receiving loop is manufactured by lithography in thin film and the at least one very low noise magnetic field transducer comprises at least one magnetoresistive sensor in thin film which is superimposed to said constriction, an insulating layer of small thickness being interposed between the at least one magnetoresistive sensor and the constriction.