3-D-Printed Circularly Polarized Twisted-Ridge Horn Antenna

A novel wideband circularly polarized (CP) horn antenna with a pair of twisted ridges is investigated in this communication. The wide impedance bandwidth is obtained by adapting a pair of exponential-shaped ridges, whereas the wide axial ratio (AR) bandwidth is achieved by twisting the ridges. The impedance matching and AR can be tuned easily and independently, which is an attractive feature of the design. An $X$ -band right-hand circular polarization (RHCP) design was simulated with CST Microwave Studio. Its metal-printed prototype was fabricated to validate the simulation. The measured 15 dB impedance and 3 dB AR bandwidths are 53% (7.43-12.80 GHz) and 65% (7.63-15.00 GHz), respectively, with an overlapping bandwidth of 51% (7.63-12.80 GHz). The measured peak antenna gain is between 8.0 and 10.1 dBic in the operating band.