Compact filtering power divider with wide passband bandwidth

In this article, a compact filtering power divider (PD) with wide passband bandwidth and high selectivity is designed and analyzed. The filtering PD is constructed by quarter- wavelength three-conductor parallel-coupled line structure terminated with two stepped impedance transmission line sections as well as an isolation resistor loaded on unique location. The even-odd mode analysis is adopted to explain the operating mechanism of signal splitting, filtering, and isolating. Then, a practical design procedure is introduced. For verification, a wideband filtering PD centered at 3.0 GHz with a fractional bandwidth of 62% is designed and fabricated. The measured results agree well with the simulated ones.