Patent · US Expired

Connectorless antenna coupler

US4740794A · kind A · utility

32Cited by
13References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 3, 1986
Grant dateApr 26, 1988
Priority date
Expiry dateJan 3, 2006

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01Q5/35
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A metal shield is dimensioned to enclose a portion of a portable radio having an internal antenna and a first transmission line. A transmission line mounted in the shield is positioned to be adjacent to the first transmission line when the shield engages the radio and permits energy to be coupled between the resonator and the first transmission line. The first transmission line and the shield are dimensioned so that the electrical length of the first transmission line increases to 2L when the shield engages the radio, where L is the electrical length of the first transmission line when the shield does not engage the radio. This electrical length transformation by an integral multiple of one half wavelength helps to maintain the input impedance to the internal antenna.

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