A Design of 3-dB Wideband Microstrip Power Divider With an Ultra-Wide Isolated Frequency Band

A 3-dB planar wideband power divider with an ultra-wide stopband and isolated frequency band is proposed. In order to extend the passband, the quasi-coupled lines are adopted. Moreover, the open and shorted stubs added at the input and output ports, respectively, can increase the bandwidths of the passband and stopband. Furthermore, in order to broaden the isolated frequency band, the impedance Ziso with the series connected resister and capacitor on the right side of the middle coupled line is adopted. The detailed derivation is proposed as well. In addition, this power divider is fabricated on the substrate Rogers RO4003C with a compact size of 15.19 mmx11.4 mm.