An Impedance-Transforming Coupled-Line Wilkinson Power Divider with Port Isolations and Extensions

An impedance-transforming coupled-line Wilkinson power divider with port isolations and extensions is proposed in this article. It is composed of a coupled line section, an isolation resistor, and three extended transmission lines at each port for physical isolation and convenient installation. By substituting additional transmission lines for the three port extensions and introducing coupled lines, the power divider achieves suppressed insertion loss with enhanced physical output isolation. Closed-form design equations are successfully derived and verified. The excellent agreement between simulated and measured results shows that the proposed power divider can realize required functions with good matching, low insertion loss, fine isolation, and wide bandwidth.