发明名称 |
Frequency variable filter, antenna duplexer, and communication apparatus incorporating the same |
摘要 |
A frequency variable filter in which both the frequency of an attenuation pole and the attenuation bandwidth can be varied. In the frequency variable filter, two serial resonance sections composed of resonators and resonance capacitors are electrically connected to each other via a capacitor. The respective resonator in each of the serial resonance sections is electrically connected in parallel with a corresponding serial circuit composed of a frequency shifting capacitor and a PIN diode. A coupling capacitor electrically connects the junctions defined respectively between the frequency shifting capacitor and the PIN diode in each of the serial circuits.
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申请公布号 |
US6522220(B2) |
申请公布日期 |
2003.02.18 |
申请号 |
US20010838815 |
申请日期 |
2001.04.19 |
申请人 |
MURATA MANUFACTURING CO., LTD. |
发明人 |
YAMADA YASUO;TSUNODA KIKUO;ATOKAWA MASAYUKI;MIYAMOTO HIROFUMI;SUEMASA HAJIME |
分类号 |
H01P1/205;H01P1/213;H03H7/12;H04B1/44;(IPC1-7):H01P1/213 |
主分类号 |
H01P1/205 |
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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