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EP1045469A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Dielectric filter, dielectric duplexer and communication apparatus

Assignee: Murata Manufacturing Co Ltd
•
Filing: 2000-03-22
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Granted: —
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Expires: 2020-03-22
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Abstract

Abstract There is disclosed a dielectric filter and a stripline filter comprising: a λ/2 resonator (R1) for generating resonance of 1/2-wavelength at a predetermined frequency, having both ends open-circuited or short-circuited; and a pair of λ/4 resonators (R2,R3) respectively for generating resonance of 1/4-wavelength at a frequency substantially equal to the predetermined frequency, each having one end open-circuited and the other end short-circuited; wherein the pair of λ/4 resonators (R2,R3) are disposed in proximity to each of both ends from the vicinity of the center of the λ/2 resonator (R1); a terminal (A) coupling to the λ/2 resonator (R1) is provided as an unbalanced terminal; and terminals (B, C) coupling to the pair of λ/4 resonators (R2,R3) is used as a balanced terminal. In the above filter, the balanced-type input/output of signals can be performed without using a balun.

Inventors

  • 👤 Motoharu c/o Murata Manufacturing Co. Hiroshima
  • 👤 Shohachi c/o Murata Manufacturing Co. Nishijima
  • 👤 Hideyuki c/o Murata Manufacturing Co. Kato

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-07 19:21
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/20; H01P1/201; H01P1/205; H01P1/2056; B; B21; B21B; B21B39/00; B21B39/02; H01P1/213; H01P1/2136; H01P5/00; H01P5/08; H01P5/10

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 139 words
A dielectric filter comprising: a λ/2 resonator (11; R1; 2a, 5a) for generating resonance of 1/2-wavelength at a predetermined frequency, having both ends open-circuited or short-circuited; and a pair of λ/4 resonators (12; R2, R3; 2b, 5b) respectively for generating resonance of 1/4-wavelength at a frequency substantially equal to the predetermined frequency, each having one end open-circuited and the other end short-circuited; wherein the pair of λ/4 (12; R2, R3; 2b, 5b) resonators are disposed in proximity to each of both ends from the vicinity of the center of the λ/2 resonator (11; R1; 2a, 5a); a terminal (A; 6) coupling to the λ/2 resonator (11; R1; 2a, 5a) is provided as an unbalanced terminal; and terminals (B, C; 7, 8) coupling to the pair of λ/4 resonators (12; R2, R3; 2b, 5b) is used as a balanced terminal.
Claim 2
Dependent Claim 23 words
The dielectric filter according to Claim 1, wherein the λ/2 resonator (R1) is bent at substantially the center of the λ/2 resonator (R1).
Claim 3
Dependent Claim 112 words
A dielectric filter comprising: a first λ/2 resonator (R11; 2a, 5a) for generating resonance of 1/2-wavelength at a predetermined frequency, having both ends open-circuited or short-circuited; and a second λ/2 resonator (R12; 2b, 5b) for generating resonance of 1/2-wavelength at a frequency substantially equal to the predetermined frequency, having both ends open-circuited; wherein the second λ/2 resonator (R12; 2b, 5b) is disposed in proximity to the first λ/2 resonator (R11; 2a, 5a); a terminal (A; 6) coupling to the first λ/2 resonator (R11; 2a, 5a) is provided as an unbalanced terminal; and two terminals (B, C; 7, 8) coupling to the second λ/2 resonator (R12; 2b, 5b) are provided as balanced terminals.
Claim 4
Dependent Claim 32 words
The dielectric filter according to one of Claims 1 to 3, wherein the λ/2 resonator (11) and the λ/4 resonator (12) are each either formed by a micro stripline or a stripline.
Claim 5
Dependent Claim 43 words
The dielectric filter according to one of Claims 1 to 3, wherein the λ/2 resonator (2a, 5a) and the λ/4 resonator (2b, 5b) are formed by a dielectric coaxial resonator comprising a dielectric block (1) on which a conductor film (3) is disposed.
Claim 6
Dependent Claim 14 words
A dielectric duplexer comprising the dielectric filter of one of Claims 1 to 5.
Claim 7
Dependent Claim 21 words
A communication apparatus comprising the dielectric filter of one of Claims 1 to 5 or the dielectric duplexer of Claim 6.

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