Star-junction multiplexers are used when the number of channels is relatively small since the resonating junction has to be connected to many filters' outputs. In this paper, novel topologies of star-junction multiplexers with resonating junctions are proposed. The advantage of the proposed topologies is that the number of connections to the resonating junction is reduced and thus allowing multiplexers with more channels to be implemented. An optimization technique is used to synthesize the coupling matrix of the proposed multiplexers, and numerical examples are illustrated in this paper.
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