A compact circularly polarized (CP) microstrip antenna with inserted nine cross slots is proposed to reduce the size and widen the beamwidth. The antenna is operated at 1.268 GHz, and built by using a substrate with a coaxial probe feed. The impedance bandwidth (VSWR < 2) is 1.5% and the 3 dB axial ratio bandwidth is 0.52%. The measure gain is 4.5 dBi and beamwidth is about 110o. The measured results for the compact CP antenna with embedded cross slots size shows that the resonate frequency is significantly lowered from 1.951 GHz to 1.268 GHz, corresponding to a 35% antenna size reduction compared with the one without any slot.
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