发明名称 |
Self-tuning radio frequency identification antenna system |
摘要 |
A self-tuning antenna that automatically adjusts its input impedance to compensate for externally induced impedance variations is provided. A variable impedance is adjusted by a control circuit to reconfigure the input impedance of than antenna to compensate for different environmental situations and different transponder mismatch situations. A negative-feedback signal is employed to determine or infer impedance mismatches and reconfigure the antenna input impedance (e.g., capacitance and/or resistance) until a desired equilibrium of the antenna input impedance is reached. A reference measurement (e.g., VSWR measurement) is automatically performed by an antenna tuning circuit that adjusts the antenna's impedance matching circuit to compensate for object interference. The antenna's impedance matching circuit includes a variable capacitor circuit having a plurality of individually controlled parallel plate capacitors that can be added or removed from the variable capacitor circuit, as necessary.
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申请公布号 |
US2007091006(A1) |
申请公布日期 |
2007.04.26 |
申请号 |
US20060357679 |
申请日期 |
2006.02.16 |
申请人 |
SANMINA-SCI, A DELAWARE CORPORATION |
发明人 |
THOBER DARIO S.;GIOLO WELLINGTON D.O.;BRECHE JEROME;CARDOSO THIAGO;FERNANDES ALECIO;XAVIER ADEMIR |
分类号 |
H01Q9/00 |
主分类号 |
H01Q9/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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