Novel nolen matrix based beamforming networks for series-fed low SLL multibeam antennas

Abstract

A new type of cascaded series feed beamforming networks (BFNs) is introduced. The network architecture is based on a dualseries Nolen matrix topology. It is able to produce tapered output amplitude distributions from N × N configurations. The general concept, analysis and systematic design of the BFNs are given. The networks are designed and intended to be used mainly for low Sidelobe Level (SLL) linear Multibeam Antennas (MBAs). Several design examples are presented, along with fabrication and measurements of an S-band prototype.