A Circularly Polarized Patch Antenna Array for Ku-Band Data-Link

This paper describes a design of a circularly polarized patch antenna array for Ku-band (14.45 GHz - 15.65 GHz) data-link for small to medium unmanned aerial vehicles. A multilayer antenna structure including the feeding network is studied in this paper. Compact size, circular polarization and bandwidth are important requirements in designing this system. The required bandwidth and circular polarization are achieved by truncating the corners of patch elements using a 90 degrees power divider and four bent slots to reduce the coupling effects and maintain the polarization purity. The antenna array is analyzed in terms of return loss, radiation pattern, axial ratio and total gain over the complete frequency band.