Modified Ring Power Divider Using Stepped-Impedance Resonator

Abstract In this paper, the design of a modified ring power divider dedicated for wideband communication or measurement systems is presented. The proposed power divider is built by using a conventional ring power divider and an additional Stepped-Impedance Resonator (SIR). The even-odd mode analysis is used to derive the design equations. In order to observe the bandwidth improvement, a comparative study between the designed device and the previously reported ring power divider is conducted. The electromagnetic (EM) simulated results show that the proposed divider has a fractional bandwidth of 90.2 % at the center frequency of 3.17 GHz. The measurement results of the fabricated prototype demonstrate high performance over the considered operational bandwidth from 1.7 GHz to 4.64 GHz with a return loss lower than −10 dB while maintaining a good insertion loss and a good isolation between the output ports. The maximum amplitude imbalance is better than 0.21 dB and the phase imbalance is better than 2.5 degrees between the output signals. The simulation and measurement results are in good agreement over the whole band of interest.