| US 7,486,192 B2 | ||
| RFID tag with frequency adjusting portion | ||
| Takashi Yamagajo, Kawasaki (Japan); Toru Maniwa, Kawasaki (Japan); and Manabu Kai, Kawasaki (Japan) | ||
| Assigned to Fujitsu Limited, Kawasaki (Japan) | ||
| Filed on May 23, 2006, as Appl. No. 11/438,368. | ||
| Claims priority of application No. 2006-049306 (JP), filed on Feb. 24, 2006. | ||
| Prior Publication US 2007/0200705 A1, Aug. 30, 2007 | ||
| Int. Cl. G08B 13/14 (2006.01) | ||
| U.S. Cl. 340—572.7 [340/572.5; 340/572.8; 343/868; 343/748] | 12 Claims |
| 12. A radio frequency identification tag comprising:
an antenna including a conductor pattern in a form of dipole, and connected to an integrated circuit chip of the radio frequency
identification tag;
a first adjusting portion including a plurality of folding points at which the conductor pattern is folded;
a second adjusting portion including an adjusting pattern having an inductance component corresponding to a length of the
adjusting pattern, and connected to the integrated circuit chip in parallel with the antenna;
a first marking portion at which instructions for an adjusting operation using the first adjusting portion are indicated;
and
a second marking portion at which instructions for an adjusting operation using the second adjusting portion are indicated,
wherein
gain of the antenna is changed by changing the folding points, and inductance of the antenna is changed by changing the length
of the adjusting pattern, wherein changing the inductance of the antenna adjusts an imaginary portion of an impedance of the
antenna.
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