A Circularly Polarized Wide-Angle Scanning Phased Array Antenna for High-Power Applications

In this paper, a high-power, wide-angle scanning circularly polarized (CP) phased array antenna is proposed, based on multi-layer microstrip structure. In order to realize CP radiation, symmetric cross slots are designed to generate two sets of orthogonal polarizations, and a planar phase shifter is designed to form <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$90^\circ$</tex> phase difference. The unit size of the proposed antenna is <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$18^*18^*6.4 \text{mm}^{3}(0.54\lambda_{0^{*}}0.54\lambda_{0^{*}}0.19\lambda_{0})$</tex>. Simulation of the infinite array shows that it achieves 10-dB impedance bandwidth of 35.6% (7.4-10.6 GHz) and 3-dB axis ratio bandwidth of 27.8% (7.8-10.3 GHz). And it achieves wide-angle scanning up to <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\pm 40^{\circ}$</tex> in both orthogonal planes. The power capacity is up to 10 kW.