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EP0422637A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Surface acoustic wave device and communication apparatus

Assignee: Hitachi Ltd
•
Filing: 1990-10-11
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Granted: —
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Expires: 2010-10-11
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Abstract

Abstract A surface acoustic wave device is disclosed for use in a communication apparatus. It has a multiple of surface acoustic wave elements (64-1 to 64-6) having different filter characteristics formed on individual piezoelectric substrates (67-1, 67-2), the different filter characteristics being synthesized to form a combined filter having a desired filter characteristic.

Inventors

  • 👤 Toyoji Tabuchi
  • 👤 Mitsutaka Hikita
  • 👤 Nobuhiko Shibagaki
  • 👤 Tetsuya Hirashima

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-08 14:55
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/125; H03H9/145; H03H9/14544; H03H9/1455; H03H9/46; H03H9/64; H03H9/6423; H03H9/6426; H03H9/6433; H03H9/6483

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 72 words
A surface acoustic wave device comprising: a first surface acoustic wave element (64-1,64-2) having a first filter characteristic; and a second surface acoustic wave element (64-1,64-2) having a second filter characteristic; wherein the first and second surface acoustic wave elements are provided on a first and second piezoelectric substrate (67-1,67-2), respectively, and the first and second filter characteristic are made to synthesize to form a combined filter having a desired filter characteristic.
Claim 2
Dependent Claim 72 words
A surface acoustic wave device comprising: a first surface acoustic wave element (64-1,64-2) having a first filter characteristic; and a second surface acoustic wave element (64-1,64-2) having a second filter characteristic; wherein the first and second surface acoustic wave elements are provided on a first and second piezoelectric substrate (67-1,67-2), respectively, and the first and second filter characteristic are made to synthesize to form a combined filter having a desired filter characteristic.
Claim 3
Dependent Claim 33 words
A surface acoustic wave device as set forth in Claim 1, wherein the first piezoelectric substrate has a first electro-mechanical coupling coefficient, and the second piezoelectric substrate has a second electro-mechanical coupling coefficient.
Claim 4
Dependent Claim 51 words
A surface acoustic wave device as set forth in Claim 1, wherein the surface acoustic wave device also comprises a first package and a second package, the first surface acoustic wave element being provided in the first package, and the second surface acoustic wave element being provided in the second package.
Claim 5
Dependent Claim 28 words
A surface acoustic wave device as set forth in Claim 1, wherein the surface acoustic wave device further comprises a signal filter (3,18) having a third filter characteristic.
Claim 6
Dependent Claim 49 words
A surface acoustic wave device as set forth in Claim 4, wherein the surface acoustic wave device further comprises a receiver and transmitter antenna, (1;141) a signal received by the antenna and a signal transmitted by the antenna being filtrated through the combined filter and the signal filter, respectively.
Claim 7
Dependent Claim 22 words
A surface acoustic wave device as set forth in Claim 4, wherein the signal filter is formed of surface acoustic wave filter.
Claim 8
Dependent Claim 96 words
A communication apparatus comprising: an antenna (1;141) for receiving or transmitting a signal; a first surface acoustic wave element (5) having a first filter characteristic electrically connected to the antenna (1;141); and a second surface acoustic wave element (3) having a second filter characteristic electrically connected to the first surface acoustic wave element (5); wherein the first and second surface acoustic wave elements are provided on a first and a second piezoelectric substrate (67-1,67-2), respectively, and the first and second filter characteristics are made to synthesize to form a combined filter having a desired filter characteristic.
Claim 9
Dependent Claim 96 words
A communication apparatus comprising: an antenna (1;141) for receiving or transmitting a signal; a first surface acoustic wave element (5) having a first filter characteristic electrically connected to the antenna (1;141); and a second surface acoustic wave element (3) having a second filter characteristic electrically connected to the first surface acoustic wave element (5); wherein the first and second surface acoustic wave elements are provided on a first and a second piezoelectric substrate (67-1,67-2), respectively, and the first and second filter characteristics are made to synthesize to form a combined filter having a desired filter characteristic.
Claim 10
Dependent Claim 33 words
A communication apparatus as set forth in Claim 7, wherein the first piezoelectric substrate (67-1) has a first electro-mechanical coupling coefficient, and the second piezoelectric substrate (67-2) has a second electro-mechanical coupling coefficient.
Claim 11
Dependent Claim 47 words
A communication apparatus as set forth in Claim 7, wherein the communication apparatus also comprises a first package and a second package, the first surface acoustic wave element being provided in the first package, and the second surface acoustic wave element being provided in the second package.
Claim 12
Dependent Claim 23 words
A communication apparatus as set forth in Claim 7, wherein the communication apparatus further comprises a signal filter having a third filter characteristic.
Claim 13
Dependent Claim 46 words
A communication apparatus as set forth in Claim 7, wherein the communication apparatus further comprises a receiver and transmitter antenna (1;141), a signal received by the antenna and a signal transmitted by the antenna being filtrated through the combined filter and the signal filter (3), respectively.
Claim 14
Dependent Claim 20 words
A communication apparatus as set forth in Claim 7, wherein the signal filter is formed of surface acoustic wave filter.

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