Gain Enhancement for Wideband CP ME-Dipole Antenna by Loading With Spiral Strip in Ku-Band

One novel single-feed single-layer wideband circularly polarized magnetoelectric dipole antenna with enhanced gain property is presented in this communication. By loading coplanar spiral with the radiating patch, the unidirectional radiation gain of the antenna is effectively improved while the impedance bandwidth and axial ratio (AR) bandwidth unaffected. Surface current distributions with/without the spiral are compared to reveal the antenna's mechanism. The measurement shows that the left-hand circular polarized antenna features the impedance bandwidth from 11.4 to 18.5 GHz (or 52%), an AR bandwidth from 13.2 to 18 GHz (or 32%), and the maximum gain of 11.1 dBic at 16.9 GHz with 3 dB gain bandwidth from 12.5 to 18.6 GHz (or 36.1%). Owning to the low profile, broadband, and high gain, the proposed antenna is a capable candidate for satellite communication.