(Received: 27-May-2020, Revised: 15-Jul.-2020 , Accepted: 3-Aug.-2020)
In this article, compact N-way Ultra Wide Band (UWB) equal and unequal split Wilkinson Power Dividers (WPDs) using exponentially λ/4 Tapered Transmission Line Transformers (TTLTs) are designed. First, 2-way WPDs are designed, simulated and then cascaded to get 4-way (equal and unequal split) and 8-way (equal split) UWB WPDs. 2- and 4-way (equal and unequal split) WPDs are fabricated and tested. The simulated and measured results of all the designed dividers are good in terms of insertion, return losses and group delay through UWB frequency band. The analysis of these dividers is carried out using the commercial ANSYS High Frequency Structure Simulator (HFSS) software package which is based on the Finite Element Method (FEM). Moreover, A MATLAB built-in function “fmincon.m” is used to find the optimum values of the three resistors chosen for perfect isolation. To validate the results, the simulation results are compared with the measured ones.

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