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A Cascaded MEMS Amplitude Demodulator for Large Dynamic Range Application in RF Receiver
Hao Yan1, Xiaoping Liao2, Chenglin Li2
1National ASIC Research Center, Southeast University, Nanjing 210096, China.
Micromachines
|December 24, 2021
Summary
This study introduces a microelectromechanical systems (MEMS) amplitude demodulator. This novel device offers a wide dynamic range for amplitude modulation (AM) signal demodulation up to 10 GHz.
Area of Science:
- Electrical Engineering
- Materials Science
- Microwave Engineering
Background:
- Traditional amplitude demodulators often face limitations in dynamic range and overload capacity.
- Microelectromechanical systems (MEMS) offer potential for miniaturized and efficient electronic components.
Purpose of the Study:
- To propose and demonstrate a novel MEMS-based amplitude demodulator with an extended dynamic range.
- To investigate the integration of capacitive and thermoelectric sensors for enhanced demodulation performance.
Main Methods:
- Implementation of a cascaded capacitive and thermoelectric sensor architecture.
- Leveraging the square-law relationship and low-pass characteristics of electromechanical and thermoelectric conversion.
- Fabrication process compatible with Gallium Arsenide monolithic microwave integrated circuit (GaAs MMIC) technology.
Main Results:
- Successful direct demodulation of amplitude modulation (AM) signals across a carrier frequency range of 0.35-10 GHz.
- Achieved a wide power measurement range from 0 to 23 dBm.
- Demonstrated high power handling capability and zero direct current (DC) power consumption.
Conclusions:
- The proposed MEMS amplitude demodulator provides a significant advancement in dynamic range and overload capacity.
- The device's compatibility with established MMIC processes facilitates potential integration into existing microwave systems.
- This MEMS solution offers a power-efficient and robust method for AM signal demodulation.
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