发明名称 |
TRANSMITTING FILTER INCLUDING SAW RESONATORS |
摘要 |
A surface acoustic wave filter includes an antenna terminal, a transmitting filter and a variable branching line both of which are coupled to the antenna terminal and a receiving filter coupled to the variable branching line. The transmitting filter has a first end series-arm SAW resonator, a second end series-arm SAW resonator, a middle series-arm SAW resonator coupled between the first and second end series-arm SAW resonators and parallel-arm SAW resonators. Each of the first and second end series-arm SAW resonator has a first resonance frequency. The middle series-arm SAW resonator has a second resonance frequency that is higher than the first resonance frequency.
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申请公布号 |
US2005134407(A1) |
申请公布日期 |
2005.06.23 |
申请号 |
US20040983788 |
申请日期 |
2004.11.09 |
申请人 |
ANASAKO KENICHI;FUJITA YOSHIAKI;EHARA HISANORI;KOMAZAKI TOMOKAZU |
发明人 |
ANASAKO KENICHI;FUJITA YOSHIAKI;EHARA HISANORI;KOMAZAKI TOMOKAZU |
分类号 |
H03H9/72;B05D3/06;B05D7/24;C23C16/44;C23C16/455;C23C16/48;H03H9/64;(IPC1-7):H03H9/64 |
主分类号 |
H03H9/72 |
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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