A Broadband Millimeter-Wave Waveguide Power Divider with High Isolation

Hua Zhang,Yun Shao,Deng Yun Shao

doi:10.11648/j.ajpa.20190704.12

Abstract

In this paper, an E-plane stepped-impedance transformer and Y-junction bifurcation are used to form a waveguide power divider with ceramic substrate loaded with thin film resistors. This structure is realized high isolation in V-band by inserting a ceramic substrate at the H-plane center of the Y-junction waveguide bifurcation, both sides of which loaded with thin film resistors. The waveguide power divider was fabricated with aluminium-50% silicon, and has characteristics of light weight, lower coefficient of thermal expansion, good thermal conductivity, and its properties are more compatible with those of ceramic substrate. The principle and design procedure are described in detail. A V-band E-plane waveguide power divider is designed, fabricated, and measured. The measured results show that insertion loss is less than 0.4dB in the frequency range of 50~60GHz, with typical isolation levels of 25dB between the two output ports and amplitude imbalance less than 0.19dB, phase imbalance less than 1.4°. The measured and simulated results show good amplitude, phase, and isolation characteristics validating the proposed power divider.

Highlights

Waveguide power divider is an important component commonly used in microwave and millimeter-wave system, which be widely used in power dividers/combiners, antenna feed systems and so on
When the two output ports are mismatched or mismatched at the same time, and the reflected power of the two output ports is inconsistent, it can be observed that the maximum electric field intensity of the input port of the power divider does not change much, and the estimated value of power-handling capability of the power divider is basically unchanged
A novel configuration of a waveguide power divider with ceramic substrate loaded with thin film resistor has been proposed

Summary

Introduction

Waveguide power divider is an important component commonly used in microwave and millimeter-wave system, which be widely used in power dividers/combiners, antenna feed systems and so on. In a power divider structure, when power is fed from an input port, the presence of other paths introduces reflection, which requires a matching structure to counteract the reflection. The machining H-plane waveguide power divider is split from the H-plane. The junction surface of the waveguide cavity is perpendicular to the wall current direction and the current path is cut off. Because millimeter-wave wavelength is short, the small slot at the junction of waveguide cavity will lead to the deterioration of waveguide performance. The machining and assembly accuracy of waveguide cavity is required to be very high

Methods

Discussion

Conclusion