Design of Unequal Wilkinson Power Divider for Tri-band Operation

Abstract—This paper presents a novel tri-band unequal Wilkinson power divider. The proposed structure is derived from the conventional unequal Wilkinson power divider by replacing the quarter-wavelength branch lines and quarter-wavelength transformers with the extended T-shaped short stubs and three-section transformers respectively. The first and third operating frequencies of the proposed Wilkinson power divider can be flexibly controlled, while the second frequency is equal to the mean value of the other two frequencies. Both of the closedform equations and design procedure are given. For verification, a triband unequal power divider with the power dividing ratio of 2 : 1 and operating frequencies of 1.3, 3.0 and 4.7 GHz is designed, fabricated and measured. The measurement results are in good agreement with the simulation ones. It is shown that the proposed power divider has simple topology and good performances in terms of insertion loss, port matching and isolation at all three operating frequency bands.