Multi-Functional Balanced-to-Unbalanced Filtering Power Dividers With Extended Upper Stopband

Two new types of multi-functional RF wide-band differential-mode-to-single-ended filtering power dividers are reported in this brief. Their first configurations exploit half-wavelength ring resonators and coupled-line sections to attain common-mode suppression throughout a broad spectral range. Furthermore, asymmetrical coupled-line stages are incorporated in more-advanced schemes to enlarge upper-stopband bandwidth. Two demonstrative microstrip prototypes for the different structures of this RF tri-functional circuit concept that operate at the 1.7-2.7-GHz 4/5-generation long-term-evolution band are built and tested.