A Wideband Balanced-to-Unbalanced Out-of-Phase Power Divider Based on Hybrid Microstrip/Slotline Structure

A wideband four-port balanced-to-unbalanced circuit with the feature of out-of-phase power division was presented in this letter. By introducing the slotline in the center ground, the common-mode noises could be suppressed by nature. In the differential-mode excitation, a differential-mode out-of-phase power divider could be realized. An isolated resistor placed in the symmetry line of two unbalanced out-ports can increase the isolation. Using the even/odd-mode circuit analysis, the corresponding equivalent circuits can be obtained. To validate the correctness of the design, a 93% fractional bandwidth balanced-to-unbalanced power divider with the feature of out-of-phase is simulated. And in the whole passband, the common-mode rejection can reach to 43 dB.