Patent EP0459391A2 successfully refreshed from Google Patents.
EP0459391A2
Expired / Lapsed
EP
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Antenna for portable radio equipment
Assignee: NEC Corp
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Filing: 1991-05-28
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Granted: —
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Expires: 2011-05-28
Abstract
Abstract An antenna (10) for portable radio equipment serves as a lambda /2 wavelength long antenna when extended (Fig.1A) or as a less than lambda /4 wavelength long antenna such as a lambda /8 wavelength long antenna when contracted (Fig.1B). Both of such antenna configurations are matched by a single matching circuit (14) with respect to impedance. The antenna radiates power efficiently in the horizontal plane. <IMAGE> <IMAGE>
Inventors
- 👤 Hiroyuki C/O Nec Corporation Iwasaki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 20:42
CPC Classifications
H; H01; H01Q; H01Q1/00; H01Q1/08; H01Q1/10; H01Q1/12; H01Q1/22; H01Q1/24; H01Q1/241; H01Q1/242; H01Q1/243; H01Q1/244
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
69 words
An antenna which is λ/2 wavelength long (λ being a wavelength of a carrier frequency used) to serve as a λ/2 wavelength long antenna when a telescopic body section of said antenna is extended or is less than λ/4 wavelength long to serve as a less than λ/4 wavelength long antenna when said body section is contracted, said antenna having substantially the same impedance when extended and when contracted.
Claim 2
Dependent Claim
23 words
An antenna as claimed in claim 1, wherein said body section is substantially λ/8 wavelength long when contracted, serving as a λ/8 antenna.
Claim 3
Dependent Claim
58 words
An antenna comprising: a telescopic body section having a wavelength which is approximately one half of the wavelength of a carrier frequency used when said body section extended or is less than one-fourth of said wavelength of said carrier frequency when said body section is contracted; and a matching circuit connected to one end of said body section.
Claim 4
Dependent Claim
25 words
An antenna as claimed in claim 3, wherein said body section comprises a conductive tube assembly made up of a plurality of telescoped conductive tubes.
Claim 5
Dependent Claim
18 words
An antenna as claimed in claim 4, wherein said plurality of conductive tubes each has a particular diameter.
Claim 6
Dependent Claim
28 words
An antenna as claimed in claim 4 or 5, wherein said conductive tube assembly is approximately 0.17 meter long when extended or approximately 0.045 meter long when contracted.
Claim 7
Dependent Claim
22 words
An antenna as claimed in any of claims 3 to 6, wherein said body section is approximately λ/8 wavelength long when contracted.
Claim 8
Dependent Claim
21 words
An antenna as claimed in claim 7, wherein said body section has substantially the same impedance when extended and when contracted.
References Cited (Backward Citations)
No citation records indexed.
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