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Updated: Jun 28, 2026
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Coupled resonator filter with single-layer acoustic coupler
Tiberiu Jamneala1, Martha Small, Rich Ruby
1Avago Technologies Inc, San Jose, CA, USA. Tiberiu.Jamneala@avagotech.com
Summary
Novel coupled-resonator filters utilize acoustic couplers for improved performance. Adding a small capacitance enhances near-band rejection, enabling fabrication of 2.45 GHz filters.
Area of Science:
- Acoustic filter design
- Resonator physics
- Microwave engineering
Background:
- Coupled-resonator filters offer simplified fabrication.
- High acoustic attenuation in coupler materials presents a challenge.
- Accurate modeling requires complex acoustic impedance and phase at high attenuation.
Purpose of the Study:
- To analyze the operation of novel coupled-resonator filters with single-layer acoustic couplers.
- To investigate methods for improving the near-band rejection of these filters.
- To demonstrate the fabrication of 2.45 GHz filters based on theoretical findings.
Main Methods:
- Employed the physical Mason model for acoustic resonator analysis.
- Treated phase and acoustic impedance as complex quantities to predict filter insertion loss.
- Connected a small capacitance between filter input and output to create tunable transmission minima.
Main Results:
- Demonstrated that a small capacitance improves near-band rejection.
- Successfully fabricated coupled resonator filters operating at 2.45 GHz.
- Validated the necessity of complex acoustic impedance and phase for accurate high-attenuation predictions.
Conclusions:
- The developed method effectively enhances the performance of coupled-resonator filters.
- The findings enable the practical fabrication of microwave filters with improved characteristics.
- Complex acoustic parameter treatment is crucial for precise filter modeling.
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