Compact Balanced Filtering Power Divider With High Common Mode Suppression level Using Spoof Surface Plasmon Polaritons
Published in IEEE Transactions on Components, Packaging and Manufacturing Technology, 2025
In this article, a compact ultra-wideband balanced filtering power divider (FPD) with controllable cut-off frequencies is proposed based on the spoof surface plasmon polaritons (SSPPs). Firstly, a compact SSPP unit cell is designed using the I-shaped microstrip structure for size miniaturization, and the dispersion characteristics are analyzed. Next, a balanced highpass power divider (PD) with high common mode (CM) suppression level is designed using the microstrip-to-slotline (MTS) transition feeding structure and T-shaped slotline structure. A differential mode (DM) highpass response and a high CM suppression level are achieved by the MTS transition feeding structure, and the function of power division is achieved by the T-shaped slotline structure. Then, by combing balanced highpass PD and low-pass SSPP structure, a balanced FPD with center frequency of 2.4 GHz and 3-dB fractional bandwidth of 116% is designed. The low and upper cut-off frequencies can be controlled independently, and in-band CM suppression level is above 35 dB. And the resistors are loaded for improving the isolation. Finally, the balanced FPD with compact size and high CM suppression level is fabricated and measured.
Citation: Y. Song, J. Yu, Q. Yang, M. Zhao, G. Liu and A. Zhang, "Compact balanced filtering power divider with high common mode suppression level using spoof surface plasmon polaritons," IEEE Trans. Compon. Packag. Manuf. Technol., vol. 15, no. 3, pp. 535-541, Mar. 2025.
