Purpose

This paper aims to design a dual mode X-band substrate integrated waveguide (SIW) bandpass filter in the conventional SIW structure. A pair of back-to-back square and split ring resonator is introduced in the single-layer SIW bandpass filter. The various coupling configurations of SIW bandpass filter using split square ring slot resonator is designed to obtain dual resonant mode in the passband. It is shown that the measured results agree with the simulated results to meet compact size, lower the transmission coefficient, better reflection coefficient, sharp sideband rejection and minimal group delay.

Design/methodology/approach

A spurious suppression of wideband response is suppressed using an open stub in the transmission line. The width and length of the stub are tuned to suppress the wideband spurs in the stopband. The measured 3 dB bandwidth is from 8.76 to 14.24 GHz with a fractional bandwidth of 48.04% at a center frequency of 11.63 GHz, 12.59 GHz. The structure is analyzed using the equivalent circuit model, and the simulated analysis is based on an advanced design system software.

Findings

This paper discusses the characteristics of resonator below the waveguide cut-off frequency with their working principles and applications. Considering the difficulties in combining the resonators with a metallic waveguide, a new guided wave structure – the SIW is designed, which is synthesized on a planar substrate with linear periodic arrays of metallized via based on the printed circuit board.

Originality/value

This study has investigated the wave propagation problem of the SIW loaded by square ring slot-loaded resonator. The electric dipole nature of the resonator has been used to achieve a forward passband in a waveguide environment. The proposed filters have numerous advantages such as high-quality factor, low insertion loss, easy to integrate with the other planar circuits and, most importantly, compact size.

中文翻译：

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紧凑型双模 X 波段 SIW 带通滤波器，具有使用分裂方形环形槽谐振器的宽杂散抑制

目的

本文旨在设计一种传统SIW结构的双模X波段衬底集成波导（SIW）带通滤波器。在单层SIW带通滤波器中引入了一对背靠背的方形和开口环谐振器。SIW 带通滤波器的各种耦合配置使用分裂方环槽谐振器，旨在获得通带中的双谐振模式。结果表明，测量结果与仿真结果一致，满足紧凑的尺寸、更低的传输系数、更好的反射系数、尖锐的边带抑制和最小的群延迟。

设计/方法/方法

使用传输线中的开路短截线来抑制宽带响应的杂散抑制。短截线的宽度和长度经过调整以抑制阻带中的宽带杂散。测得的 3 dB 带宽为 8.76 至 14.24 GHz，中心频率为 11.63 GHz、12.59 GHz 时的部分带宽为 48.04%。采用等效电路模型进行结构分析，仿真分析基于先进的设计系统软件。

发现

本文讨论了波导截止频率以下谐振器的特性及其工作原理和应用。考虑到谐振器与金属波导结合的困难，设计了一种新的导波结构——SIW，它是在平面基板上合成的，具有基于印刷电路板的金属化通孔的线性周期阵列。

原创性/价值

本研究研究了方环槽加载谐振器加载的 SIW 的波传播问题。谐振器的电偶极子特性已被用于在波导环境中实现正向通带。所提出的滤波器具有许多优点，例如高品质因数、低插入损耗、易于与其他平面电路集成以及最重要的是尺寸紧凑。