A wideband circularly polarized slot-antenna array

In this paper, a wideband circularly polarized (CP) slot-antenna array is presented. A feeding network with four output ports is designed using metamaterial transmission line (MM TL) to feed four slot antenna elements, forming a sequential-rotation array (SRA) and resulting in CP operation. The antenna array is studied and designed using computer simulation and measurement. The measured results show that the antenna array has a wide impedance bandwidth (IMBW) of 0.92-3.65 GHz (2.73 GHz, 119.5%) and axial-ratio bandwidth (ARBW) of 1.43-3.59 GHz (2.16 GHz, 86.1%).