Patent US3398306A successfully refreshed from Google Patents.
Patent US5940040A successfully refreshed from Google Patents.
US5940040A
Expired / Lapsed
US
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System for selecting between a whip antenna and a built-in antenna
Assignee: Panasonic Holdings Corp
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Filing: 1997-08-13
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Granted: 1999-08-17
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Expires: 2017-08-13
Abstract
Abstract An antenna system comprises: a whip antenna and a built-in antenna for diversity reception; an antenna select switch for selecting one of the antennas and connecting the selected one to a radio circuit; and a transmission line length adjusting circuit, inserted between the antenna select switch and the whip antenna, for controlling a terminal load condition of the whip antenna, when the built-in antenna is connected to the radio circuit.
Inventors
- 👤 Yoshio Koyanagi
- 👤 Tsukasa Takahashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 01:33
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/12; H01Q1/22; H01Q1/24; H01Q1/241; H01Q1/242; H01Q1/243; H01Q1/244; H01Q1/52; H01Q1/521; H01Q21/00; H01Q21/28; H01Q21/29; H01Q3/00; H01Q3/24; H04; H04B; H04B7/00; H04B7/02; H04B7/04; H04B7/06; H04B7/0602; H04B7/08; H04B7/0802; H04B7/0825
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
70 words
An antenna system comprising: a whip antenna and a built-in antenna for diversity reception; an antenna select switch for selecting one of said antennas and connecting said selected one to a radio circuit; and a transmission line length adjusting circuit, inserted between said antenna select switch and said whip antenna, for controlling a terminal load condition of said whip antenna, when said built-in antenna is connected to said radio circuit.
Claim 2
Dependent Claim
70 words
An antenna system comprising: a whip antenna and a built-in antenna for diversity reception; an antenna select switch for selecting one of said antennas and connecting said selected one to a radio circuit; and a transmission line length adjusting circuit, inserted between said antenna select switch and said whip antenna, for controlling a terminal load condition of said whip antenna, when said built-in antenna is connected to said radio circuit.
Claim 3
Dependent Claim
46 words
The antenna system of claim 1, wherein said antenna select switch comprises a further select switch for connecting a termination circuit, which is for controlling an impedance of said whip antenna, to said antenna select switch, when said built-in antenna is connected to the radio circuit.
References Cited (Backward Citations)
US4633519A
Cited
EP0210746A2
Cited
US4914714A
Cited
US4803447A
Cited
US4958382A
Cited
US5493311A
Cited
US5659886A
Cited
US5734355A
Cited
EP0680161A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-08-16 | 2003-02-15 | 2003-08-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-08-16 | 2007-02-15 | 2007-08-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-08-16 | 2011-02-15 | 2011-08-17 | $7700.00 | Window Closed / Lapsed |