A Wideband suspended Microstrip Patch Antenna

ABSTRACT In this paper we propose a circularly polarized (CP) microstrip antenna on a suspended substrate with a coplanar capacitive feed and a slot within the rectangular patch. The antenna has an axial ratio bandwidth (< 3 dB) of 10.66%. The proposed antenna exhibits a much higher impedance bandwidth of about 32.12% (S11 < −10 dB) and also yields return loss better than −15 dB in the useful range of circular polarization. It has been found that this antenna offers higher directivity with good radiation properties required for GPS system and mobile applications. The resulting circular polarization bandwidth (with axial ratio ? 3 dB) has been found to meet that required for this application. The proposed antenna possesses a high gain of 6.0 dB overall the GPS (1575 MHz) and mobile (1800/1900 MHz) operation.