Novel Design of Wilkinson Power Dividers With Arbitrary Power Division Ratios

In this paper, a stub-loaded transmission line that is used to design Wilkinson power dividers with arbitrary power division ratios is discussed in depth. Power division is always required in most wireless/wireline communications such as industrial systems and consumer electronics. However, the design of an unequal Wilkinson power divider, particularly with a large division ratio, becomes a challenge in engineering because of the impractical realization of the high- or low-impedance transmission lines on a dielectric substrate. In this paper, we first introduce a transmission-line structure and perform theoretical analysis. The derivations reveal that the studied structure can be utilized to design Wilkinson power dividers with equal or unequal power divisions. For demonstration purposes, two power dividers with division ratios of 1 : 1 and 1 : 9, respectively, and operating in the popular industrial, scientific, and radio-frequency identification frequency bands are implemented by loading distributed transmission-line elements, namely, open- or short-circuited stubs. The demonstrators are also fabricated and validated by measurements, and good agreement between the experimental results and the simulated responses is observed.