发明名称 |
Filter circuit having an acoustic surface-wave filter device |
摘要 |
A filter circuit includes an acoustic surface-wave filter device having an input transducer comprised of a set of interleaved electrodes disposed on a first portion of a body of piezo-electric material adapted to propagate acoustic surface waves for producing an acoustic surface-wave signal in response to an input signal applied to the input transducer, and an output transducer comprised of a set of similar interleaved electrodes disposed on a second portion of the piezo-electric body spaced a selected distance from the first portion for receiving the acoustic surface-wave signals so as to produce a corresponding output signal having a selected frequency response. The frequency response (e.g., bandwidth) of the acoustic surface-wave filter device is controlled by selectively changing the number of conductor elements constituting the interleaved electrodes of the input and output transducers. An amplifier drives the acoustic surface-wave filter device, the gain and output impedance of the amplifier being changed as the frequency response of the acoustic surface-wave filter device changes, so as to compensate for corresponding changes in the insertion loss and input impedance of the filter device.
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申请公布号 |
US4021761(A) |
申请公布日期 |
1977.05.03 |
申请号 |
US19760652615 |
申请日期 |
1976.01.26 |
申请人 |
SONY CORPORATION |
发明人 |
MORII, KOKICHI;URAYAMA, KEN-ICHI |
分类号 |
H03H9/145;H03H3/08;H03H9/00;H03H9/64;(IPC1-7):H03H9/04;H03H9/26;H03H9/32;H03F13/00 |
主分类号 |
H03H9/145 |
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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