Zero-Degree TL Based Dual-Band Wilkinson Power Divider for Multi-Band Wireless Applications

In this paper, a new dual-band Wilkinson power divider (PD) featuring simple structure, miniaturized size, and high design flexibility is presented, whose function is mainly realized by a novel dual-band biasing network (DBN). Compared to the conventional one, the half-wavelength transmission lines (TLs) are replaced by zero-degree composite right- and lefthanded (CRLH) TLs, which configuration results in a compact size, and high design flexibility that different with the previous CRLH-TL based dual-band studies, the impedance of the utilized CRLH-TL can be freely selected. Meanwhile, closed-form design equations are derived and can be mathematically utilized to introduce a large number of passbands. For demonstration, a dual-band Wilkinson PD centered at 1.90 GHz and 2.45 GHz is designed and fabricated. It is worth noting that the two frequencies are chosen so that the first frequency is for LTE mobile communication, while the other band is for wireless fidelity (WIFI), Bluetooth, etc. Good agreement between the theoretical and experimental results can be observed. Besides the low in-band insertion loss and full-ports matching properties, the proposed PD also features a good out-of-band rejection performance.