Broadband circularly polarized microstrip antenna for airborne x band cp-sar

This paper presents a novel design of broadband circularly polarized microstrip antenna as an element of airborne X-band circularly polarized synthetic aperture radar (CP-SAR) sensor. The antenna is designed in low weight, low cost, low profile of configuration, and will transmit and receive left-handed circular polarization (LHCP) or right handed circular polarization (RHCP). The proposed antenna is an element of airborne CP-SAR that will be implemented into arrays that consist eight array submodule. For broaden the bandwidth, prototype constructed by double-layers substrate that has low dielectric constant and dissipation factor. Proximity-coupled feed stripline feeding adopted to avoid complexity in feeding network configuration. Basic characteristics of antenna parameters such as return loss, axial-ratio, and radiation pattern investigated and presented.