Unequal Wilkinson power divider with wide range of arbitrary power division based on recombinant technology

An arbitrary ratio Wilkinson power divider with large power dividing ratio is analysed and demonstrated in this study. This kind of Wilkinson power divider is constructed by incorporating equal (or unequal) power divider cells, recombinant structures, extra low power branches and transformers for matching the circuits. The proposed structure is compatible with single-layer printed circuit board fabrication process. The structure is analysed in detail, while the formulas are given as design guidelines. Moreover, this method is extended to unequal power dividers based on three-way Wilkinson power divider with larger dividing ratio. To verify the proposed design approach, the prototypes of 5:1, 7:1 and 11:1 unequal power divider are optimised, fabricated and measured. The measured bandwidth of 20 dB return loss are about 10, 10 and 6%, respectively, while the isolations of the output ports are better than 20 dB. Good agreements can be observed between the simulated and measured results. The phase differences of output ports are within ±3° over 10% fractional bandwidth.