A Miniaturized 4: 1 Unequal Wilkinson Power Divider Using Artificial Transmission Lines and Double-Sided Parallel-Strip Lines

A 4 : 1 unequal Wilkinson power divider using microstrip artificial transmission lines (ATLs) is proposed. For the ATL, a series of meandered-line inductors, parallel-plate capacitors, and interdigital capacitors are employed. The designed power divider is composed of three ATLs, and a method has been proposed using technology of ATLs and double-sided parallel-strip lines (DSPSLs) to design line of high characteristic impedance. Microstrip line with very high characteristic impedance of over 150 Omega has been achieved by this method, which cannot be easily achieved by conventional transmission lines because of comparably thin conductor width. The fabricated 4 : 1 unequal power divider has good operational performance and occupies 55.3 mm x 37.8 mm, which is only about 40% of area compared to a conventional one at 0.9 GHz.