Theory and Design of a Flexible Two-Stage Wideband Wilkinson Power Divider

Antra Saxena,Mohammad Hashmi,Muhammad Akmal Chaudhary,Deepayan Banerjee

doi:10.3390/electronics10172168

Abstract

This article presents the design scheme of a wideband Wilkinson Power Divider (WPD) with two-stage architecture utilizing quarter-wave transmission lines and short-circuit stubs. The bandwidth of the proposed WPD is flexible and can be controlled using the design parameters. The proposed design achieves excellent isolation between output ports in addition good in-band performance. The analysis of the proposed circuit results in a simplified transfer function which is then equated with a standard band-pass transfer function to determine the parameters of transmission lines, stub’s impedances, and the value of the isolation resistors. Furthermore, it is also demonstrated that a simple alteration in the proposed circuit enables the design of a wideband DC isolated WPD that maintains a good in-band and isolation performance. A number of case studies have been included to highlight the flexibility of the proposed design. Two distinct prototypes are developed on different boards to demonstrate the wideband performance of the proposed design. An excellent agreement between the experimental and measured results for both the designs over a wide band including very good isolation between ports validate the proposed design.

Highlights

The isolation issues are readily addressed by Wilkinson Power Divider (WPD) [5]
The WPD in its original form makes use of quarter-wavelength transmission line that limits the intrinsic bandwidth at a single frequency
The measured insertion losses at output ports, S21 and S31 are −3.0 ± 0.4 dB which are comparable to the simulated results of −3 dB

Summary

Introduction

The advancements in communication protocols and standards have led to a number of innovations in both active and passive circuits, components and devices [1,2,3,4]. Within the passive components regime, there have been a plethora of design reports on advanced configurations for power divider, impedance transformer, directional coupler etc. In the context of power dividers, the T-junction configuration can be considered the most fundamental but it is constrained by poor isolation between the output ports. The isolation issues are readily addressed by Wilkinson Power Divider (WPD) [5]. The WPD achieves good matching at the ports and exhibits excellent isolation between the output ports. There have been extensive advancements in the WPD design techniques to meet the requirements of multi-standard communication systems. A majority of the research focus in the last decade has largely been on multi-band [6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22] and broadband WPDs [23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58]

Methods

Results

Conclusion