Design Method of Shared Aperture S/C-Band Array Antenna Based on Thinned

This paper proposes a design method for thinned array-based aperture-sharing antenna for S/C-band applications. The operating frequencies of the proposed antenna are 3~3.2 GHz in the S band and 6~6.4 GHz in the C band. The single element design uses two RF-35 substrates and achieves a reflection coefficient below −10 dB in the aforementioned operating bands. The measured antenna gains are 6.64 and 6.65 dBi in S and C bands, respectively. To realize aperture sharing for the designed S/C-band single-radiating element, a thinned array-based aperture-sharing array antenna is proposed using the binary genetic learning particle swarm optimization (GLPSO) algorithm. The S-band array antenna of the transmitter shows a half-power beamwidth (HPBW) of 9°, and the sidelobe level of the C-band array antenna of the receiver is −20 dB.