Patent · US Expired

Dual antenna assembly with antenna retraction inactivation

US5353036A · kind A · utility

176Cited by
12References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 8, 1992
Grant dateOct 4, 1994
Priority date
Expiry dateJul 8, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01Q1/244
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

An antenna assembly comprises an elongate antenna element (11) mounted in a support (5) and movable between a retracted position (see FIG. 2) and an extended position (see FIG. 1). A helical antenna element (12) is carried at one end of the elongate element. The support (5) comprises a pair of concentric conductors (9,10) which provide a coaxial feed to the antenna elements (11, 12). Suitably the support (5) comprises a dielectric tube (6) having respective conductive portions (9,10) provided on the inner and outer faces thereof. The elongate antenna element is slidably mounted within the central conductor (9). In the retracted position both ends of the elongate antenna element are electrically connected to the central conductor (9). The elongate antenna element is thus rendered inactive as a radiating element and essentially becomes part of the central coaxial feed coupled directly to the helical antenna element. The invention provides a compact and convenient dual antenna arrangement ideally suited for use in a portable cellular radio telephone.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.