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A Two-Channel DFT Spectrum Analyzer for Fluctuation Enhanced Sensing Based on a PC Audio Board
Emanuele Cardillo1, Graziella Scandurra1, Gino Giusi1
1Department of Engineering, University of Messina, 98100 Messina, Italy.
Sensors (Basel, Switzerland)
|July 2, 2021
Summary
This study presents a low-cost, portable dual-channel spectrum analyzer using a USB sound card for Fluctuation Enhanced Sensing. It enables low-frequency noise measurements down to DC by upconverting signals, making advanced sensing accessible.
Area of Science:
- Instrumentation and Measurement
- Signal Processing
- Applied Physics
Background:
- Fluctuation Enhanced Sensing requires low-frequency noise measurements.
- Portable measurement systems are highly desirable.
- Standard spectrum analyzers often lack DC capability or portability.
Purpose of the Study:
- To propose a dual-channel spectrum analyzer capable of low-frequency measurements down to DC.
- To achieve portability and low cost using readily available hardware.
- To enable Fluctuation Enhanced Sensing applications with enhanced accessibility.
Main Methods:
- Utilizing a USB sound card for data acquisition.
- Employing a simple modulation board to upconvert low-frequency signals (down to DC) to higher frequencies within the sound card's range.
- Numerical reconstruction of the full spectrum using efficient software based on a public domain library.
Main Results:
- Demonstration of a dual-channel spectrum analyzer with DC frequency response.
- System construction on a low-cost single-board computer (Raspberry PI3).
- Achieved portability and isolation from electromagnetic interference via an optical TCP/IP link.
Conclusions:
- The proposed method provides a cost-effective and portable solution for low-frequency spectrum analysis.
- This approach significantly enhances the accessibility of Fluctuation Enhanced Sensing.
- The system offers a compact and robust spectrum analyzer suitable for various applications.
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