A novel microstrip diplexer based on coupled line

Abstract

ABSTRACTA novel diplexer operated at 1.8 GHz and 2.4 GHz is proposed. It is based on the coupled microstrip line and features low insertion loss, high isolation, simple topology, and compact size. As compared with the conventional diplexer type, both channel selecting filters and T-junction of the proposed diplexer are avoided by introducing a pair of coupled line and matching stubs. A prototype circuit of the proposed diplexer is developed and examined experimentally. The simulated and measured results are in good agreement, confirming the proposed design method.