US6801101B2
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dielectric filter, dielectric duplexer, and communication apparatus
Assignee: Murata Manufacturing Co Ltd
•
Filing: 2003-01-09
•
Granted: 2004-10-05
•
Expires: 2023-01-09
Abstract
Abstract A dielectric filter including: a λ/2 resonator for generating resonance of ½-wavelength at a predetermined frequency, having both ends open-circuited or short-circuited; and a pair λ/4 resonators respectively for generating resonance of ¼-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 are disposed in proximity to each of both ends from the vicinity of the center of the λ/2 resonator; a terminal coupling to the λ/2 resonator is provided as an unbalanced terminal; and terminals coupling to the pair of λ/4 resonators 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 Hiroshima
- 👤 Shohachi Nishijima
- 👤 Hideyuki Kato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:15
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
94 words
A dielectric filter comprising: a first λ/2 resonator for generating resonance at a length of substantially ½ wavelength at a predetermined frequency, said first λ/2 resonator having both ends open-circuited or short-circuited; a second λ/2 resonator for generating resonance at a length of substantially ½ wavelength at a frequency substantially equal to the predetermined frequency, said second λ/2 resonator having both ends open-circuited, said second λ/2 resonator disposed in proximity to said first λ/2 resonator; an unbalanced terminal coupled to the first λ/2 resonator; and a balanced terminal coupled to the second λ/2 resonator.
Claim 2
Dependent Claim
94 words
A dielectric filter comprising: a first λ/2 resonator for generating resonance at a length of substantially ½ wavelength at a predetermined frequency, said first λ/2 resonator having both ends open-circuited or short-circuited; a second λ/2 resonator for generating resonance at a length of substantially ½ wavelength at a frequency substantially equal to the predetermined frequency, said second λ/2 resonator having both ends open-circuited, said second λ/2 resonator disposed in proximity to said first λ/2 resonator; an unbalanced terminal coupled to the first λ/2 resonator; and a balanced terminal coupled to the second λ/2 resonator.
Claim 3
Dependent Claim
19 words
The dielectric filter according to claim 1 , wherein each said λ/2 resonator comprises a microstripline or a stripline.
Claim 4
Dependent Claim
18 words
The dielectric filter according to claim 1 , wherein each said λ/2 resonator comprises a dielectric coaxial resonator.
Claim 5
Dependent Claim
52 words
A dielectric duplexer comprising the dielectric filter of claim 1 , and further comprising a second dielectric filter having two balanced or unbalanced terminals, wherein a respective terminal of said second dielectric filter and a corresponding terminal of said first-mentioned dielectric filter are interconnected to provide a common terminal of said duplexer.
Claim 6
Dependent Claim
49 words
A communication apparatus comprising the dielectric duplexer of claim 4 , further comprising an antenna terminal connected to said common terminal of said duplexer, and a transmission circuit and a reception circuit connected respectively to corresponding ones of said terminals other than the terminals connected to said antenna terminal.
Claim 7
Dependent Claim
40 words
A communication apparatus comprising the dielectric filter of claim 1 , and further comprising a high frequency circuit including at least one of a transmission circuit and a reception circuit, said dielectric filter being connected to said high frequency circuit.
References Cited (Backward Citations)
JPH06500442A
Cited
US5497137A
Cited
US5557246A
Cited
JPH07254807A
Cited
US5489882A
Cited
JPH08265048A
Cited
US5697088A
Cited
EP0869574A2
Cited
US6292070B1
Cited
US6133806A
Cited
US6426725B2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-10-05 | 2008-04-05 | 2008-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-10-05 | 2012-04-05 | 2012-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-10-05 | 2016-04-05 | 2016-10-05 | $7700.00 | Window Closed / Lapsed |