Abstract: The invention concerns an RF-type contactless chip card, comprising a sensor coil (1), an electronic circuit (2) connected to the coil and an antenna (3) made form a material with high magnetic permeability, including a first part located substantially in the plane of the coil upper surface (A), a second part located substantially in the plane of the coil lower surface (B) and a connecting part (C) located in the center of the coil. The latter part is dimensioned relative to the antenna (3) such that the voltages induced at its terminals are of the same order of magnitude, whether the antenna is parallel or perpendicular to the lines of flux generated by a reader.

Abstract: The invention concerns a chip card associated with RF transmission means. Said chip card comprises on each surface high permeability zones arranged so as to concentrate the flux generated by the RF transmission means onto a sensor coil. To ensure the proper functioning of the system, the transmission means generate flux lines parallel to the surface of the chip card.