| US 7,535,364 B2 | ||
| Antenna apparatus | ||
| Isao Sakama, Hiratsuka (Japan); and Minoru Ashizawa, Tokyo (Japan) | ||
| Assigned to Hitachi, Ltd., Tokyo (Japan) | ||
| Filed on Dec. 13, 2005, as Appl. No. 11/299,671. | ||
| Claims priority of application No. 2005-244375 (JP), filed on Aug. 25, 2005. | ||
| Prior Publication US 2007/0046465 A1, Mar. 01, 2007 | ||
| Int. Cl. G08B 13/14 (2006.01) | ||
| U.S. Cl. 340—572.7 [340/572.1] | 27 Claims |
| 1. An antenna apparatus for making communication with a radio frequency IC tag to read information stored in an integrated
circuit chip included in the radio frequency IC tag and serving as a reader/writer, comprising:
a radiating antenna which generates an electric field by electric power supplied to a feeding point thereof; and
an auxiliary antenna which resonates by the electric field generated by the radiating antenna to generate an induced current;
the radiating antenna and the auxiliary antenna having the same length,
the auxiliary antenna comprising a plurality of conductive elements arranged in an array, each conductive element having the
same length as that of said radiating antenna, and
the plurality of conductive elements being disposed on the same plane and parallel to each other.
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