A CFAR-Enhanced Spectral Whitening Method for Acoustic Sensing via UAVs
Abstract
:1. Introduction
2. Background Information
3. CFAR-Enhanced Whitening
3.1. Description
3.2. Validation
4. Experimental Results & Discussion
5. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Sampling Frequency () | 48 kHz | Number of Signals | 4 |
Decimation Factor | 8 | FFT Window | 0.5 s |
IIR Step Size () | 5 × 10−4 | Window Overlap | 50% |
Notch Radius () | 0.995 | Padded Length () | 12,000 pts |
Harmonics Removed () | 8 | Spectral Resolution () | 0.5 Hz/bin |
Detector Type | OS-CFAR | Noise Samples ( | 101 |
Forgetting Factor () | 0.2 | Order Statistic ( | |
Flooring Factor () | 0.5 | Guard Cell Band () | 5.5 Hz |
Noise Band () | 50 Hz | Guard Cells () | 12 |
Noise Sample Band () | 1–1000 Hz | Consecutive Detections () | 2 |
Test Band () | 150–550 Hz | Cell Deviation () | 1 |
Guard Cell Band () | 10.5 Hz | Maxima Tested () | 2 |
Noise Samples () | 1998 pts | 1.0 × 10−3 | |
Test Cells () | 801 pts | 6.5 × 10−1 | |
Guard Cells (G) | 22 pts | 8.2 × 10−4 | |
Order Statistic () | 2 | 2.5 × 10−3 | |
Consecutive Trials () | 2 |
= 200 Hz | = 500 Hz | |||
---|---|---|---|---|
Unwhitened | Whitened | Unwhitened | Whitened | |
Detection Rate (ST, BI, RBI) | 64%, 54%, 55% | 100%, 97%, 99% | 69%, 37%, 51% | 100%, 63%, 83% |
Max SNR | 28 dB | 38.3 dB | 26.5 dB | 47.4 dB |
Average SNR | 12.4 dB | 19.7 dB | 8.2 dB | 32.5 dB |
Initial Detection | 13.25 s | 13 s | 11 s | 10.5 s |
Second Detection | 20.25 s | 13.25 s | 12 s | 10.75 s |
Observed Frequency Range | 212–190 Hz | 523–479 Hz |
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Harvey, B.; O’Young, S. A CFAR-Enhanced Spectral Whitening Method for Acoustic Sensing via UAVs. Drones 2018, 2, 1. https://doi.org/10.3390/drones2010001
Harvey B, O’Young S. A CFAR-Enhanced Spectral Whitening Method for Acoustic Sensing via UAVs. Drones. 2018; 2(1):1. https://doi.org/10.3390/drones2010001
Chicago/Turabian StyleHarvey, Brendan, and Siu O’Young. 2018. "A CFAR-Enhanced Spectral Whitening Method for Acoustic Sensing via UAVs" Drones 2, no. 1: 1. https://doi.org/10.3390/drones2010001