Wideband High-Selectivity Filtering All-Frequency Absorptive Power Divider With Deep Out-of-Band Suppression

In this article, a novel wideband high-selectivity filtering power divider (FPD) with all-frequency absorptive performance is presented. It is based on two cascaded coupled-line (CL) sections loaded with half-wavelength open-circuit stubs and three resonator absorptive stubs. To realize all-frequency absorption of the RF-input-power, three simple absorptive stubs composed of quarter-wavelength short-circuit stubs series with resistors are applied. By introducing the CL sections with half-wavelength open-circuit stubs, the power divider (PD) is easy to realize wideband high-selectivity filtering performance and deep stopband suppression. Besides, the impedances of the open-circuit stubs can be independently adjusted to control the bandwidth. Furthermore, explicit design equations and limitations of implementations are derived and discussed. Good agreements between the simulated and measured results verify the correctness of the design theory.