A new design of compact microstrip Wilkinson power dividers

Abstract

A novel compact microstrip Wilkinson power divider with an easy design and fabrication is proposed in this paper. Through capacitive or inductive loading of both of the quarter-wave transmission lines and the isolated resistor employed in conventional Wilkinson power dividers, reduction of the transmission line segments from g/4 to g/30 is obtained. Therefore, the proposed structure can distinctly save the occupied area. Furthermore, some useful design equations based on odd-even mode analysis for the proposed circuit model are introduced to provide an accurate method to design compact Wilkinson power dividers. The fabricated power divider designed for the frequency of 800MHz is 84% smaller than conventional ones, and has a 120MHz bandwidth for which the input return loss is better than 20-dB. Within this bandwidth, the insertion loss is less than 0.3-dB and the isolation between the outputs more than 20-dB.Index Terms-Wilkinson power divider, compact size, capacitive or inductive loading, quarter-wave transmission lines.

Rigorous Analysis and Investigation of the Bandwidth Broadening Mechanism in a Compact Power Divider With Physical Port Isolation

“…Among them, reactive loading technique was proposed [4][5][6] in which the isolation termination remained purely resistive. Further size reduction was made possible by introducing complex isolation networks (INWs) containing reactive components in addition to the resistive one [7][8][9][10][11][12]. In [7], both the capacitive loading and the complex INW were applied and the overall size was reduced to /30 (is the wavelength at the center frequency of operation).…”

“…Further size reduction was made possible by introducing complex isolation networks (INWs) containing reactive components in addition to the resistive one [7][8][9][10][11][12]. In [7], both the capacitive loading and the complex INW were applied and the overall size was reduced to /30 (is the wavelength at the center frequency of operation). Despite the very compact size achieved, the main issue was the very limited space between the split ports.…”

A Novel Compact Size Wilkinson Power Divider With Two Transmission Zeros for Enhanced Harmonics Suppression

“…Since these designs depend only on microstrip lines, the post fabrication tuning is not possible to overcome the deviation between measured and required response if any. Therefore, lumped elements are presented, which play extra important roles in miniaturization and harmonic suppression such as capacitive loaded [13] and inductive loaded-based designs [14,15].…”

“…In this paper, the inductor loaded design is adopted with the addition of two transmission zeros to improve the harmonic suppression performance by utilizing extra stub and a transmission line. Through even and odd mode analysis, the general design equations have been derived in closed form with the advantage of choosing the harmonic order which are required to be suppressed to suppressed [13] as in Section 2. Based on the derived equations, a design flows as well as design curves are proposed to facilitate the calculation-to-fabrication procedure, in Section 3.…”