Extremely unequal Wilkinson power divider with dual transmission lines

A new method to design an unequal Wilkinson power divider (UWPD) with a high power-dividing ratio is presented. By employing dual transmission lines, the ratio of highest to lowest characteristic impedance in the UWPD is effectively reduced while maintaining the main frequency response, thus the conventional narrow width in the microstrip can be avoided in practical implementation. For verification, a 5:1 microstrip UWPD operating at 1 GHz has been designed, fabricated and tested. Results show that there is good agreement between calculation and measurement.