A Band-Pass Filter Based on Half-Mode Substrate Integrated Waveguide and Spoof Surface Plasmon Polaritons

Area of Science:

• Electromagnetics and Wave Propagation
• Microwave Engineering
• Materials Science

Background:

• Substrate integrated waveguide (SIW) technology is widely used in microwave circuits.
• Spoof surface plasmon polaritons (SSPPs) offer unique waveguiding properties at lower frequencies.
• Existing band-pass filters often face limitations in size, bandwidth, and loss.

Purpose of the Study:

• To propose and analyze a novel band-pass filter.
• To integrate half-mode substrate integrated waveguide (HMSIW) with double-layer SSPPs.
• To achieve compact size, wide bandwidth, and low loss in microwave frequencies.

Main Methods:

• Design of a band-pass filter utilizing HMSIW and double-layer SSPPs with periodic grooves.
• Parametric study to analyze the influence of key parameters on filter performance.
• Equivalent circuit modeling to elucidate the physical mechanism.

Main Results:

• The proposed filter demonstrates independent control over low and high cut-off frequencies.
• Achieved a wide bandwidth of 69.77% (15.6-32.1 GHz) with insertion loss greater than -0.8 dB.
• Simulated and measured results show good agreement, validating the filter's performance.

Conclusions:

• The developed HMSIW and SSPP-based band-pass filter offers superior performance compared to existing structures.
• The filter exhibits a smaller size, wider bandwidth, and lower loss.
• The proposed design holds significant potential for microwave frequency applications.