A Shared-Aperture Broadband Circularly Polarized Antenna for Satellite Communications and Navigation

A shared-aperture broadband circularly polarized antenna for satellite communications and navigation is presented in this paper. This developed antenna deploys a 2×2 crossed- dipole antenna array and a 4×4 microstrip antenna phased array sharing a common aperture. With this compact scheme, the high aperture reuse efficiency can be achieved. The 2×2 crossed-dipole antenna array is designed to cover B1~B3 bands of Beidou satellite navigation system (BDS) while the 4×4 microstrip antenna phased array is designed to operate in S-band for satellite communications. The broadband phase-shift network with dual-probe feeding and four-probe feeding are employed to broaden the circularly polarized band respectively. The simulated results show that the relative operating bandwidth of the presented antenna is 34.5% in L-band and 38.1% in S-band.