Design of a Dual-Band Three-Way Power Divider with Unequally High Power Split Ratio

In this paper, a dual-band three-way power divider with unequally high power split ratio is proposed. The dual-band operation is achieved by using a two-section impedance transformer, and to reach a high split ratio, transmission lines with impractical high characteristic impedances are replaced with dual–band T-shaped structures. The design is conducted with a thorough analysis and systematic design procedure for facilitating the rapid development of the prototypes. To verify the effectiveness of the proposed design method, an example of a power divider with a power split ratio of 7:5:1 is investigated, fabricated, and measured on a Rogers RO4003C substrate. Good agreements between the simulation and measurement results are obtained. Compared with several three-way unequal dual-band power dividers in previous works of the others, our proposed power divider delivered the highest power split ratio while still retaining good performance of insertion loss, return loss, and isolation between output ports.