360° scanning multi-beam antenna based on homogeneous ellipsoidal lens fed by circular array

Presented is a multi-beam antenna which can realise 360° switching scanning in azimuth. The antenna system is composed of a homogeneous ellipsoidal lens and a planar circular tapered slot antenna (TSA) array. Each TSA element is fed with a rectangular waveguide by a special waveguide-to-TSA transition. Beam scanning can be achieved by switching between the waveguide feeders. A Ku-band Teflon ellipsoidal lens fed with 20 Fermi-TSAs has been fabricated. Measurements show that the sidelobe levels of the 20 beams are all below-17 dB and the gain differences are all within +0.4 dB.