×

Passive transponder

  • US 4,890,111 A
  • Filed: 10/20/1987
  • Issued: 12/26/1989
  • Est. Priority Date: 10/22/1986
  • Status: Expired due to Term
First Claim
Patent Images

1. A passive radio frequency transponder comprising two antenna elements coupled by a non-linear passive electronic component and by a conductor arranged in parallel with said passive electronic component, each of said antenna elements being formed by a metallic ribbon arranged in a planar loop surrounding a space devoid of any metallic elements, and said loops each having the general form of a rectangular trapezoid with a small base, a large base and a side perpendicular to said bases, wherein said small bases face and are parallel to one another, said electronic component is connected between said small bases, said perpendicular sides are aligned with one another and connected by a conductive portion formed by a metallic ribbon having a width less than the width of said perpendicular sides and disposed so its outer edge is aligned with the outer edge of said perpendicular sides, and said perpendicular sides each includes a rectilinear slot extending parallel to its length, closed on the side of said large base and opened on the side of said small base proximate said conductive portion, said conductor thus being formed by the portions of said perpendicular sides which are located outwardly of said slots and by said conductive portion, and the space bounded by the antenna elements, the passive electronic component and the conductor having substantially the form of a T, the horizontal bar of which is formed by said slots and the vertical bar of which is formed by said space separating said small bases between said passive electronic component and said conductor.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×