Wideband Circularly Polarized Phased Array Antenna for K/Ka-Band Satellite Communication Using ME-Dipole Elements

This letter presents a new K/Ka-band circularly polarized (CP) phased array antenna (PAA) using magneto-electric dipole (ME-dipole) elements. First, a novel CP ME-dipole element is proposed, combining two technologies, namely asymmetric radiating patches and asymmetric crossed slot, to achieve a CP axial ratio bandwidth (ARBW) of 23% [(24.5 to 31.0) GHz]. Then, the PAA is formed using the sequential rotation technology to further increase the ARBW by 13% to 36% [(22.5 to 32.5) GHz], covering the entire impdence bandwidth (IBW). This is achieved while ensuring symmetry in scanning patterns and maintaining CP purity across the entire scanning angles. The fabricated 4 x 4 PAA offers a wide scanning range of +/- 56 degrees, +/- 45 degrees, and +/- 41 degrees at 22.5 GHz, 27.5 GHz, and 32.5 GHz with a scan loss of less than 3 dB. These excellent performances make the proposed PAA ideal for CP satellite communication (SatCom) terminal applications, covering the K-band [(22.5 to 27.5) GHz] and Ka-band [(27.5 to 32.5) GHz].