Compact filtering unequal Wilkinson power divider with 1:15 power dividing ratio using composite right/left handed-coupled lines

A novel design approach for a compact unequal Wilkinson power divider (WPD) with arbitrary large power dividing ratio, 1:15, and filtering response based on composite right/left-handed coupled-line (CRLH-CL) circuit structure is proposed and investigated. The presented structure is stemmed from a typical unequal WPD by utilizing asymmetric CRLH-CL section as a λ/4 transformer between input and output ports and integrating two CRLH-CL band-pass filter transformers near the output ports. The analytical closed-form design equations for the proposed structure are derived and a design procedure for physical implementation is presented. To theoretically verify the proposed design approach, a 1:15 filtering WPD operating at center frequency of 1.4 GHz, is designed and simulated.