Broadband Eight-Way Substrate Integrated Waveguide Radial Power Divider/Combiner With High-Isolation

Kaijun Song,Yong Fan,Yuxuan Chen,Te Kong

doi:10.1109/access.2020.2986339

Abstract

A broadband eight-way substrate integrated waveguide (SIW) radial power divider/combiner with high-isolation is presented. The step probes are utilized to achieve broadband impedance matching and improve the return loss. What's more, the star structure based on microstrip circuit is employed to improve the isolation performance. A two-layer SIW radial power divider/combiner is designed, fabricated and measured. Good agreement between simulated and measured results is achieved for the proposed power divider/combiner. The measured results show that both bandwidths of the input and output port are 25% and 20% when their return loss are lower than -15 dB. The measured output isolation is greater than 17.5 dB from 5.75 GHz to 7.85 GHz and greater than 20 dB from 6.8 GHz to 7.9 GHz. The presented eight-way SIW power divider/combiner has the advantage of wider bandwidth, lower return loss and insertion loss, and higher isolation between the outputs.

Highlights

With the rapid development of radio frequency (RF) and microwave systems, high power and small size have become major development trends
The isolation network is realized by microstrip structure
The proposed power divider/combiner adopts the step plated holes to improve the impedance matching of the input port and the output ports, while the star structure based on microstrip circuit is employed to improve the isolation performance between the outputs and miniaturize the dimension

Summary

INTRODUCTION

With the rapid development of radio frequency (RF) and microwave systems, high power and small size have become major development trends. In [14], a SIW differential radial power combiner design is presented based on changing the electric field polarity of selected probes It greatly simplifies the design and modelling, and has good phase and amplitude balance. In [16], an eight-way radial power divider with ring-shape isolation network is proposed It has a certain isolation, but its matching performance between the output ports of the radial power divider is poor and insertion loss is relatively high. The proposed power divider/combiner adopts the step plated holes to improve the impedance matching of the input port and the output ports, while the star structure based on microstrip circuit is employed to improve the isolation performance between the outputs and miniaturize the dimension. The proposed power divider/combiner realizes the miniaturized size, and has a high isolation performance and a good matching performance between the output ports

ANALYSIS AND DESIGN

Findings

CONCLUSION