Development of shared aperture dual configuration antenna for S/Ka-band communication

Shared aperture dual configuration antenna has been developed for dual linearly/circularly polarized operation at S/Ka-band. The antenna operates in cassegrain configuration at Ka-band and in prime focus configuration at S-band using the same parabolic reflector. Measured gain of the overall antenna at Ka-band is better than 48 dBi in each port and interport isolation is better than 19 dB. Measured gain at S-band is better than 28 dBi in each port and interport isolation is better than 20 dB. Measured 2:1 VSWR bandwidth is better than 7% at either port at Ka-band and is about 10% at either port at S-band. Measured 3-dB axial-ratio bandwidth is better than 7% at each port at Ka-band.