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A THz Waveguide Bandpass Filter Design Using an Artificial Neural Network
Chu-Hsuan Lin1, Yu-Hsiang Cheng1
1Graduate Institute of Communication Engineering, National Taiwan University, Taipei City 10617, Taiwan.
Micromachines
|June 24, 2022
Summary
Researchers developed a 300 GHz waveguide bandpass filter using asymmetric inductive irises and artificial neural networks. The novel filter achieves low insertion loss and high return loss, crucial for terahertz applications.
Area of Science:
- Electrical Engineering
- Electromagnetics
- Terahertz Technology
Background:
- Waveguide filters are essential components in high-frequency communication systems.
- Designing filters for the terahertz (THz) frequency range presents unique challenges due to component size and precision requirements.
Purpose of the Study:
- To design and fabricate a 300 GHz waveguide bandpass filter with specific performance characteristics.
- To explore the application of artificial neural networks (ANNs) in optimizing filter geometry for desired frequency responses.
Main Methods:
- Utilized coupling matrix synthesis to design a 6-pole Chebyshev filter.
- Employed an artificial neural network (ANN) to determine optimal filter geometries based on frequency response targets.
- Fabricated the filter using computer numeric controlled (CNC) milling for high precision.
Main Results:
- The fabricated filter operates in the 276-310 GHz range.
- Achieved an insertion loss of less than 3 dB.
- Demonstrated a return loss better than 17 dB, indicating efficient signal transmission and minimal reflection.
Conclusions:
- The study successfully demonstrates a high-performance 300 GHz waveguide bandpass filter.
- The integration of ANNs offers an effective approach for optimizing complex microwave and THz component designs.
- The achieved performance metrics are suitable for advanced THz system applications.
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