Concentric ring array of connecting spirals with WAVES

International audienceA dual circularly polarized wideband array working over a 2:1 bandwidth was previously developed. This array had the following requirements: 2:1 bandwidth, capable of steering up to 30° in theta, dual circular polarization, Relative Sidelobe Level (RSLL) <; -10dB, Axial Ratio (AR) <; 3dB and reflection coefficient (S11) <; -10dB. In this paper, we extend the array bandwidth to 15:1 through adding connections between the arms of neighboring spirals to improve the S11 at lower frequencies and using the WAVES (Wideband Array with Variable Element Size) technique to reduce the RSLL at higher frequencies