Broadband circularly-polarised slot antenna array

Abstract

A stacked slot antenna is proposed and studied to improve the performance of a circularly-polarised (CP) annular-ring slot antenna that has the disadvantages of a narrow bandwidth, a lower gain and bidirectional radiation. The stacked antenna structure is composed of a circular wide slot, a parasitic patch and a metallic reflector, and its CP radiation is excited through the proximity coupling of an L-shaped microstrip line. A 4×4 array using the stacked slot antenna as an element is also developed and designed at X-band. Details of the antenna design and obtained results are presented.