US3918062A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Receiving loop antenna system
Assignee: Panasonic Holdings Corp
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Filing: 1974-07-24
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Granted: 1975-11-04
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Expires: 1994-07-24
Abstract
Abstract In a receiving loop antenna especially adapted for use as a built-in antenna of a portable wireless set and of the type wherein the antenna output terminals are so tapped that power matching impedance of the wireless set may be attained, a circuit having series resonant circuit characteristics and a transmission line connected in series with the circuit and having such a length that impedance matching may be obtained, which may minimize the noise at or in the proximity of the center frequency of the frequency band of the series resonant circuit, are inserted between the antenna output terminals and the input terminals of the wireless set.
Inventors
- 👤 Hiroshi Haruki
- 👤 Yoshiyasu Hiroi
- 👤 Kyohei Fujimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:53
CPC Classifications
H; H01; H01Q; H01Q7/00; H01Q1/00; H01Q1/12; H01Q1/22; H01Q1/24; H01Q1/241; H01Q1/242; H01Q1/243
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
133 words
In A receiving loop antenna system especially adapted for use as a built-in antenna which consists of a loop antenna and a grounding plate perpendicular to the loop antenna for a portable wireless set, the antenna output terminals being tapped at such points that said antenna may be matched with the input impedance of said wireless set, the improvement comprising a series-connected circuit comprising a. a circuit having series resonant circuit characteristics and tuned to the center frequency of the operating frequency range of said wireless set, and b. a transmission line having such a length as to attain the impedance matching which minimizes the noise in the proximity of said center frequency, said series-connected circuit being inserted between the output terminals of said antenna and the input terminals of said wireless set.
Claim 2
Dependent Claim
133 words
In A receiving loop antenna system especially adapted for use as a built-in antenna which consists of a loop antenna and a grounding plate perpendicular to the loop antenna for a portable wireless set, the antenna output terminals being tapped at such points that said antenna may be matched with the input impedance of said wireless set, the improvement comprising a series-connected circuit comprising a. a circuit having series resonant circuit characteristics and tuned to the center frequency of the operating frequency range of said wireless set, and b. a transmission line having such a length as to attain the impedance matching which minimizes the noise in the proximity of said center frequency, said series-connected circuit being inserted between the output terminals of said antenna and the input terminals of said wireless set.
Claim 3
Dependent Claim
84 words
A receiving loop antenna system as defined in claim 1 wherein ther length l of said transmission line is determined to satisfy the following relation ZF ZR ((1 + jtan Beta l) / (S + j tan Beta l)) where ZF impedance at which the noise matching of said wireless set may be attained; ZR impedance at which the power matching of said wireless set may be attained; S (1 + (ZF - ZR) )/ (1 - (ZF-ZR)/* *(ZF+ ZR) ); and Beta coefficient.
Claim 4
Dependent Claim
21 words
A receiving loop antenna system as defined in claim 1 wherein said series tuning circuit comprises an inductor, and a capacitor.
Claim 5
Dependent Claim
49 words
A receiving loop antenna as defined in claim 1 wherein said circuit having series resonant circuit characteristics; a series circuit consisting of a capacitor and an inductor; and parallel resonant circuits each consisting of an inductor and a capacitor, being connected with both ends of said series circuit respectively.
Claim 6
Dependent Claim
26 words
A receiving loop antenna as defined in claim 1 wherein said loop antenna and said circuit having series resonant characteristic are coupled through impedance conversion transformer.
References Cited (Backward Citations)
US3736591A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-03 | 1979-05-05 | 1979-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-03 | 1983-05-05 | 1983-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-03 | 1987-05-05 | 1987-11-04 | $7700.00 | Window Closed / Lapsed |