Over-Size Pill-Box Window for Sub-Terahertz Vacuum Electronic Devices

Tongbin Yang,Dun Lu,Xuesong Yuan,Chaoyang Zhang,Jie Xie,Wenjie Fu,Yang Yan,Xiaotong Guan

doi:10.3390/electronics10060653

Tongbin Yang, Dun Lu + Show 6 more

Open Access

https://doi.org/10.3390/electronics10060653

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Abstract

The pill-box window is one of the important components of microwave vacuum electronic devices (VEDs), and research into it is of great significance. As the operating frequency increases, the problems associated with the reduction in the structure size include the reduction of the brazing plane and the reduction in the tolerance of the pill-box window. These problems will cause traditional pill-box windows to be unsuitable in high-frequency bands, especially in terahertz and sub-terahertz regions. The most influential factor is the length of the circular waveguide in the box window. The welding plane of the over-size pill-box window is the annular bottom surface on both sides of the dielectric sheet, which is larger than the circular waveguide, and the operating frequency does not directly affect the area of the brazing surface. Choosing a suitable diameter for the dielectric sheet can effectively increase the tolerance to the length of the pill-box window circular waveguide. Therefore, an over-size pill-box window would be a practicable approach to improve the performance compared to the traditional pillow-box in high-frequency bands. This paper describes, in detail, the theoretical design, simulation optimization and experimental process of this improved pill-box window. An over-size pill-box window suitable for G band VEDs was successfully developed. The experimental result in the 215–225 GHz band is that the maximum transmission loss is −1 dB, and the overall transmission loss is close to −0.5 dB. The overall reflection is less than −11 dB.

Highlights

In Recent decades, with the rapid development of terahertz science and technology, the lack of terahertz radiation sources has become, have limiting the research into and applications of the terahertz wave
The components of the over-size pill-box window are cleaned and dimensioned, and components with qualified dimensions are selected for assembly, and the first test is performed on the vector network analyzer (CEYAER AV3672C (Shandong, China))
This paper introduces the design, production and testing of a pill-box window developed for G band Vacuum electronic devices (VEDs)

Summary

Introduction

In Recent decades, with the rapid development of terahertz science and technology, the lack of terahertz radiation sources has become, have limiting the research into and applications of the terahertz wave. In the high-frequency pill-box window experiment process, the error capacity of the circular waveguide length (L1) is the biggest factor affecting the pill-box window test results.

Results

Conclusion