Advances in Microwave and Millimeter Filtering Circuit Design

Dear Colleagues,

Microwave and millimeter-wave filtering circuits and devices are essential components in modern wireless communication, radar, satellite, sensing and electronic systems. Beyond conventional standalone filters, the integration of frequency-selective responses with antennas, power dividers, couplers, baluns, amplifiers and other functional components has become an effective approach to reducing circuit size, insertion loss, interconnection complexity and system cost.

The rapid development of 5G/6G communications, satellite networks, automotive radar, the Internet of Things and highly integrated radio-frequency front ends has created increasing demand for filtering circuits with high selectivity, low loss, wide bandwidth, compact size, high isolation, reconfigurability and multifunctional integration. Recent advances in substrate-integrated waveguides, spoof surface plasmon polaritons, metamaterials and metasurfaces, integrated passive devices, superconducting technologies, acoustic-wave devices, additive manufacturing and reconfigurable materials are enabling innovative filtering circuits with enhanced electrical and integration performance.

Meanwhile, artificial intelligence is transforming the conventional design paradigm for microwave devices. Machine learning, deep learning, electromagnetic surrogate modeling, physics-informed neural networks and intelligent optimization provide promising solutions for rapid response prediction, topology optimization, inverse design, tolerance analysis and the automated design of complex filtering circuits.

This Special Issue aims to present recent theoretical, computational, technological and experimental advances in microwave and millimeter-wave filtering circuit design. Original research articles, review papers and short communications addressing novel filtering mechanisms, multifunctional circuit architectures, AI-assisted design methods, fabrication and integration technologies, measurement techniques and emerging system applications are welcome.

Topics of interest include, but are not limited to, the following:

• Microwave and millimeter-wave filtering circuit synthesis and design;
• Novel resonators, coupling structures and frequency-selective mechanisms;
• Planar, waveguide, SIW, cavity and integrated filtering circuits;
• Filtering antennas and antenna–filter co-design;
• Filtering power dividers, couplers, baluns and amplifiers;
• Diplexers, multiplexers and multifunctional filtering devices;
• Multiband, wideband, tunable and reconfigurable filtering circuits;
• Metamaterial-, metasurface- and SSPP-based filtering devices;
• AI-assisted microwave device design and electromagnetic surrogate modeling;
• Inverse design, topology optimization and robust design;

We look forward to receiving your contributions.

Prof. Dr. Pin Wen
Dr. Kai Xu
Dr. Fan Liu
Guest Editors

Manuscript Submission Information

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