Ultra-wideband Wilkinson Power Dividers Based on Substrate Integrated Coaxial Line

The power divider plays an important role in feeding microwave and millimeter-wave array antennas. In this paper, two ultra-wideband Wilkinson power dividers using substrate integrated coaxial line (SICL) are presented. A 2-Way Wilkinson power divider is fabricated and the measured results are consistent with the simulated ones. From 10.9-34.5 GHz, the return loss is lower than -10 dB with a fractional bandwidth of 104%. The insertion loss is less than 0.5 dB from 13-33.9 GHz and the isolation is greater than 15 dB from 10.2-33 GHz. In addition, the amplitude imbalance of two ports is only 0.1 dB from 10-32.8 GHz and the size is only 32.4 mm
²
. On the basis of this, a 4-Way Wilkinson power divider is implemented. The measured results indicate that it has a fractional bandwidth of 75% from 15.5- 34.1 GHz. The isolation is more than 15 dB at a frequency range of 14-31.8 GHz.