To surely identify an article by suppressing the absorption of radio waves transmitted from a transmission coil for making an operating distance relatively long, and preventing the deterioration of the L values of reception and transmission coils.
An identification tag 11 is attached to an article 16, and provided with a reception coil 12 and a transmission coil 13 and an RFID(radio frequency identification) element 14 with which the reception and transmission coils 12 and 13 are connected. The reception and transmission coils 12 and 13 are wound around a single magnetic core member 18 made of magnetic materials so that magnetic field directions generated when currents are allowed to flow in the coils can orthogonally cross each other on a face in parallel with a mounting face 16a of an article 16. The article 16 is made of magnetic materials, and a non-magnetic and conductive electromagnetic shielding plate 17 or an electromagnetic shielding foil is bonded to the reception and transmission coils 12 and 13 faced to the mounting face 16a of the article 16. A transmission antenna 22 and a reception antenna 23 are mounted on a questioner 21 so that the magnetic field directions can orthogonally cross each other.
YONEZAWA MASA
TSUCHIDA TAKASHI
HACHIMAN SEIRO
