Patent ID: 6842145

Claim:
A reduced size GPS microstrip antenna comprising: (a) a first dielectric substrate; (b) a second dielectric substrate mounted on an upper surface of said first dielectric substrate; (c) a ground plane mounted on a bottom surface of said first dielectric substrate; (d) a shaped layer of etched copper mounted on an upper surface of said second dielectric substrate; (e) first and second rectangular shaped quarter-wavelength microstrip antennas mounted on said upper surface of said second dielectric substrate, said first and second quarter-wavelength microstrip antennas being spaced apart from and electrically separated from said ground plane by said first and second dielectric substrates, said first and second quarter-wavelength mcirostrip antennas being adapted to receive an RF carrier signal containing GPS (Global Positioning System) data; (f) said first quarter-wavelength microstrip antenna being rotated ninety degrees with respect to said second quarter-wavelength microstrip antenna on the upper surface of said second dielectric substrate; (g) a feed network mounted on the upper surface of said first dielectric substrate, said feed network having one end of a first feed line and one end of a second feed line connected thereto, said first feed line having an opposite end thereof connected to said first quarter-wavelength microstrip antenna, said second feed line having an opposite end thereof connected to said second quarter-wavelength microstrip antenna, said first and second feed lines forming a power divider which provides for a phase shift of 90° of an electrical equivalent signal of said RF carrier signal when transmitted through said first and second feed lines; and (h) said phase shift of said electrical equivalent signal and said first quarter-wavelength microstrip antenna being rotated ninety degrees with respect to said second quarter-wavelength microstrip antenna, providing for a circular polarization of said GPS microstrip antenna.