Theory and Experiment of Multiport Filtering Power Divider With Arbitrary Division Ratio Based on Dielectric Resonator

This paper presents a novel and simple design approach of multiport power divider with arbitrary power splitting ratio as well as filtering response. The relationship between the external Q-factors (Q es) and power splitting ratio is theoretically analyzed, and it is found that the power allocation for the multiple outputs is determined by their Qe's ratio. By altering the Q es of the splitting ports, the power ratio can be arbitrarily controlled while the output total Qe is equal to the input Qe. Based on this, the two functions of power division and bandpass response of the proposed filtering divider can be designed independently. Accordingly, two practical three-way filtering power dividers with different division ratios (1:1:1 and 3:1:1) using the same topology based on the dielectric resonator (DR) are constructed for the first time. Both of them can be easily built by properly changing the lengths of feeding probes for the output DR without increasing the circuit size, while the phase difference between the splitting ports mainly depends on the direction of the feeding probes. To verify the proposed design concept, the two filtering power dividers with different division ratios mentioned above are implemented and measured. Comparisons of the measured and simulated results show good accordance and verify the theoretical predications.