This paper presents a novel compact Wilkinson Power Divider (WPD) that improves harmonics suppression. The proposed WPD consists of a shunt open stub between two series similar inductors, and a microstrip line between an isolation resistor and each output port. This configuration acts as a low-pass filter with two transmission zeros. In addition, it facilitates manufacturability by using lower transmission line impedance values than conventional structures. Through Even and odd mode analysis, the general design equations have been derived in closed form. A 2 GHz microstrip WPD is designed, fabricated and measured based on the proposed technique. A great agreement has been obtained between the measured performance of fabricated WPD circuit and the simulation results. The measured results show that the second and third harmonic levels are about -47 dBc and -35 dBc, respectively. The proposed design has about 40% reduction in size better than conventional WPD. It achieves competing results compared to other published work.
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