A new type of cascaded series feed beamforming networks (BFNs) is introduced. The network architecture is based on a dual-series Nolen matrix topology. It is able to produce tapered output amplitude distributions from NxN 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.
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