Patent · US Expired

Antenna apparatus for capacitively coupling an antenna ground plane to a moveable antenna

US5440315A · kind A · utility

63Cited by
8References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 24, 1994
Grant dateAug 8, 1995
Priority date
Expiry dateJan 24, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01Q1/084
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

An antenna apparatus for a hand-held symbology reader device having a housing and an elongated one-quarter wavelength antenna. A rotatable coupling member has an L-shaped conductor fixedly and electrically coupled to the antenna by a first end thereof. A second end of the L-shaped conductor is rotatably received by the housing. A ground plane of an electrically conductive material, having a plastic film coated thereon, is positioned within the housing. A washer of an electrically conductive material is electrically coupled to the second end of the L-shaped conductor, and is positioned in face-to-face juxtaposition with a portion of the ground plane. The washer and the portion of the ground plane form a parallel plate capacitor, with the plastic film forming a dielectric therebetween to capacitively couple the ground plane to the antenna. The antenna may be repeatedly rotated from an upright, transmitting/receiving position to a stowed position, without damage to the device or electrical disconnection between the antenna and the ground plane.

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