Patent Number: 6,166,638

Title: RF/ID transponder with squinted beam radiation pattern using dipole-over-ground plane antenna

Abstract: An RF/ID transponder comprises an integrated circuit package including at least a memory and an RF modulator. A dipole antenna is coupled to the RF modulator, and has a length greater than one-half wavelength of an electromagnetic wave having a nominal frequency within an operating frequency band of the RF modulator. A base plate provides an electrically conductive ground plane, and a housing is attached to the base plate. The integrated circuit package and the dipole antenna are supported by the housing at a predetermined distance from the conductive ground plane. Thereby, the dipole antenna provides a radiation pattern that includes at least first and second squinted beams extending at respective acute angles relative to a vector defined normal to the conductive ground plane, and at least one center beam extending along the vector defined normal to the conductive ground plane. In a preferred embodiment of the invention, the length of the dipole antenna is approximately one and one-half wavelengths at the nominal frequency, and the housing supports the dipole antenna above the conducting ground plane at a distance of approximately 6 to 12 percent of a wavelength of the nominal frequency.

Inventors: Brady; Michael John (Brewster, NY), Duan; Dah-Weih (Yorktown Heights, NY)

Assignee: Intermec IP Corp.

International Classification: H01Q 9/28 (20060101); H01Q 9/04 (20060101); H01Q 1/22 (20060101); G08B 013/14 ()

Expiration Date: 12/26/2017