Multi-isolation Resistors in Coupled Line Section for Wilkinson Power Divider and Its Optimization

By analyzing the equivalent circuit of coupled line section, three potential isolation resistor positions are investigated for Wilkinson power divider application in this letter. Design equations of Wilkinson power divider with multi-isolation resistors are newly derived in closed-form. After optimization, five designable cases (Case I~V) with one isolation resistor are summarized and compared in details. Finally, one circuit (Case IV) is selected, fabricated and measured. Measured and simulated results are matched very well. The purpose to investigate the multi-isolation resistance position could be quite useful to improve the isolation performance of multi-way or multi-section power divider topologies.