In-Phase and Anti-Phase Power Dividers for UWB Differentially Fed Antenna Arrays

This letter presents two novel power dividers operating in the FCC frequency range from 3.1 to 10.6 GHz. The two outputs of each power divider are coplanar striplines, while the input is a microstrip line. Hence, the power dividers act as baluns and are suited for differentially fed antennas. The in-phase version shows a return loss of better than 15 dB from 1 to 12.3 GHz, whereas for the anti-phase version the return loss is better than 10 dB from 1 to 12.3 GHz. Besides the characterization of the dividers, a linear antenna array fed by one of the dividers is shown, and measurement results in the time domain and frequency domain are presented. The mean gain of the realized four-element array is 9.7 dBi.