Design of probe-fed circularly-polarized rectangular-patch thick microstrip antenna revisited

Circularly polarized (CP) microstrip antennas are largely employed in GPS receivers. Consequently, the international antenna community has devoted much effort to the theoretical and experimental research on this kind of radiator [1], overcoming many of its inherent limitations [2]. However, in spite of these efforts, the technique used to compensate for the probe inductance, when a coaxial probe is used to feed an electrically thick (a known practical way to increase bandwidth [l]-[3]) microstrip antenna, still relies on the expertise of the designer [4]-[5]. To overcome this limitation, an efficient technique for designing probe-fed CP rectangular-patch electrically thick microstrip antenna without any external network is proposed.