| 摘要 |
PROBLEM TO BE SOLVED: To surely perform data demodulation, without bringing about a special drop in a receiving distance by arranging the end faces of bar-shaped magnetic cores to face opposite each other with a gap between them, while their central axes are arranged on the same straight line so that the bar-shaped magnetic cores of 1st and 2nd loop antennas can be on the same magnetic field axis in the same substrate. SOLUTION: A 1st loop antenna has a 1st coil 22, a bar-shaped magnetic core 21 passing has a capacitance 23 it and connected serially or in parallel. A 2nd loop antenna device has a 2nd coil 25 which resonates in parallel in a resonance frequency which is substantially the same as in the 1st loop antenna, capacitance 26 and a bar-shaped magnetic core 24 passing through the 2nd coil 25. Then, the 1st and 2nd loop antennas are arranged, so that the cores 21 and 24 of the 1st and 2nd loop antennas exist on the same magnetic field axis in the same substrate, while their central axes are arranged on the same straight line with their end faces opposite to each other and with a gap between them.
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