Analysis on the Radiation Property of the Bounded Modes of Periodic Leaky-Wave Structure with Finite-Length Using a Hybrid Method.

Zheng Li,Zhan Zhang,Jianjie Duan,Meie Chen,Junhong Wang

doi:10.1038/srep22917

Abstract

In this paper the radiation property of the one-dimensional periodic leaky-wave structure is analysed using a new hybrid method, which involves the mode expansion method for expanding the periodic aperture field in terms of spatial harmonics and the method of effective radiation sections for transforming the expanded fields into far fields. Using this method, the radiation of each spatial harmonic can be achieved, and the contributions of the harmonics (especially the bounded modes) to the total radiation of the periodic leaky-wave structure can be calculated. The main findings in this paper demonstrate that the bounded modes in a finite length structure have obvious contribution to the far-field radiation, which was considered to be non-radiative and always ignored in the conventional researches.

Highlights

The bounded modes involved in a periodic aperture field can be seen as a series of uniform slow waves
In this paper, taking the leaky rectangular waveguide (LRWG) as an example, the radiation property of one-dimensional periodic leaky-wave structure is studied with a new hybrid method, which involves the mode expansion method and the Effective Radiation Sections (ERSs) method
The periodic aperture field of the LRWG can be efficiently expanded into spatial harmonics

Summary

Introduction

The bounded modes involved in a periodic aperture field can be seen as a series of uniform slow waves (ignoring attenuation). In order to extract the propagation constant of each spatial harmonic from the periodic aperture field, mode expansion must be implemented.

Results

Conclusion