A Compact Wideband Lumped-Element Wilkinson Power Divider Using Inverting Coupled Coil

This letter presents a lumped-element wideband Wilkinson power divider (WPD) with C–L– $C~\pi $ -network. Based on the inverting coupled coils and capacitive loading, the proposed WPD can achieve compact circuits and wideband performance. The design equations for the proposed WPD are derived by even–odd modes analysis techniques. As an example, a WPD using Rogers 4003C is implemented for verification. The measurement and simulation results are presented to confirm the theory’s validity. The compact size of the power divider is $0.165\lambda \text{g}\,\,\times 0.0625\lambda \text{g}$ without input and output transmission lines (TLs). The power divider has a minimum insertion loss (IL) of 0.47 dB. The measured isolation is greater than 16 dB, and return loss (RL) is better than 15 dB over a range of 0.88–2.02 GHz and a relative operating bandwidth of 78.6%.