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A Quasi-Lumped Element Tunable Bandpass Filter Based on GaAs Technology
1The Innovation Center for Electronic Design Automation Technology, School of Electronics and Information (School of IC Science and Engineering), Hangzhou Dianzi University, Hangzhou 310018, China.
Micromachines
|March 28, 2026
Summary
This study introduces a compact, tunable bandpass filter on gallium arsenide (GaAs) chip. It achieves continuous frequency tuning from 5.4 to 6.2 GHz, ideal for miniaturized electronic systems.
Area of Science:
- Electrical Engineering
- Materials Science
- Microwave Engineering
Background:
- Miniaturization of electronic components is crucial for modern devices.
- Tunable filters are essential for flexible radio frequency (RF) systems.
- Gallium arsenide (GaAs) technology offers high performance for RF applications.
Purpose of the Study:
- To design and fabricate a miniaturized, continuously tunable bandpass filter chip.
- To enhance frequency selectivity using transmission zeros.
- To validate the filter's performance through simulation and measurement.
Main Methods:
- Utilized quasi-lumped elements instead of spiral inductors.
- Integrated on-chip PN-junction varactor diodes and Metal-Insulator-Metal (MIM) capacitors.
- Employed source-load coupling and grounded series LC resonators for three transmission zeros.
Main Results:
- Achieved continuous tunability of the operating frequency by tuning coupling capacitance and LC resonators.
- Fabricated filter occupies a compact die area of 1.35 × 1.365 mm².
- Measured center frequency tuning range from 5.4 to 6.2 GHz, matching simulations.
Conclusions:
- The proposed miniaturized continuously tunable filter design is validated.
- The filter demonstrates excellent frequency selectivity and tunability.
- This GaAs-based filter is suitable for compact, high-performance RF applications.
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