Three-Way Wideband Filtering Power Dividers With Enhanced Power Dividing Ratio and High Isolation

In this paper, a novel topology for the multiway filtering power divider with a large power dividing ratio (PDR) is proposed. A three-line coupled structure and a λ/2 open-ended stub are introduced between the input port and the power dividing junction to reduce the requirement for high impedance in the low-power path and obtain filtering performance. The PDR is significantly enhanced, and the out-of-band rejection is improved. Meanwhile, a wideband port-to-port isolation is achieved through the isolation network. To verify the validity of the proposed methodology, two three-way wideband filtering power dividers with the power ratios of 5:3:2 and 8:1:1 are designed. The simulated and measured results demonstrate that the 5:3:2 (8:1:1) power divider has the bandwidth of 51.57% (48.5%) with the return loss less than −15 dB and the isolation bandwidth 80% (102%) with reference to −20 dB.