A Dual-Wideband Circular Polarized Shared-Aperture Antenna for CubeSat Applications

A dual-wideband circular polarized shared aperture antenna for CubeSat applications is presented in this paper. The antenna exploits two distinct components operating at separate bands. The S-band antenna is based on a stacked patch structure. Circular polarization with a single feeding point is achieved by truncating the corners of both patches. The X-band antenna adopts an S-inverted printed dipole where the upper patch of the S-band antenna acts as a ground plane. An alternative technique to feed the printed dipole avoiding the use of a balun is then proposed. The shared aperture antenna shows a -10dB impedance bandwidth from 1.92 to 2.16 GHz and from 7.2 to 10 GHz in S- and X- band, respectively. These performances are able to cover the downlink and uplink frequencies for the Earth Exploration Satellite Services (EESS). An AR below 3dB in the S-band and below 1.5dB in the X-band within the EESS bandwidths is achieved.