All-Metal Wideband Circularly Polarized High-Gain Antenna for Space-borne Applications

A novel all-metal wideband circularly polarized antenna with high-gain used for Space-borne applications is proposed. The antenna should be mainly constructed by metal because of the harsh environment of the space navigation (lower temperature and higher radiation). The key innovation of the paper is the all-metal antenna element providing wideband circularly polarized, which is combined by a crossed dipole and a magneto-electric dipole. The single-fed configuration simplify the feeding network and the antenna processing. A prototype is fabricated with size of $550 \times 550 \times 40 \mathrm{~mm}^{3}$ and exhibits the $\mathbf{- 1 2. 5 d B}$ bandwidth of $1.12-2.15 \mathrm{GHz}$. The proposed antenna fed by air stripline and consists of 4 subarrays. The fabricated $4 \times 4$ subarray can be used to demonstrated the antenna design. A wider bandwidth of $1.12-2.15 \mathrm{GHz}$ with 18.1 dBic of the subarray verified the aperture efficiency reached 83%. The operating frequency of this antenna can cover all satellite navigation frequencies in the L-band and can be widely used in the field of remote sensing systems.