Laser Doppler Signal Denoising Based on Wavelet Packet Thresholding Method
In laser Doppler velocimeter (LDV), calculation precision of Doppler shift is affected by noise contained in Doppler signal. In order to restrain the noise interference and improve the precision of signal processing, wavelet packet threshold denoising methods are proposed. Based on the analysis of D...
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Wiley
2019-01-01
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| Series: | International Journal of Optics |
| Online Access: | http://dx.doi.org/10.1155/2019/1097292 |
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| author | Da Zhang Ranglei Liu |
| author_facet | Da Zhang Ranglei Liu |
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| collection | DOAJ |
| description | In laser Doppler velocimeter (LDV), calculation precision of Doppler shift is affected by noise contained in Doppler signal. In order to restrain the noise interference and improve the precision of signal processing, wavelet packet threshold denoising methods are proposed. Based on the analysis of Doppler signal, appropriate threshold function and decomposition layer number are selected. Heursure, sqtwolog, rigrsure, and minimaxi rules are adopted to get the thresholds. Processing results indicate that signal-to-noise ratio (SNR) and root mean square error (RMSE) of simulated signals with original SNR of 0 dB, 5 dB, and 10 dB in both low- and high-frequency ranges are significantly improved by wavelet packet threshold denoising. A double-beam and double-scattering LDV system is built in our laboratory. For measured signals obtained from the experimental system, the minimum relative error of denoised signal is only 0.079% (using minimaxi rule). The denoised waveforms of simulated and experimental signals are much more smooth and clear than that of original signals. Generally speaking, denoising effects of minimaxi and saqtwolog rules are better than those of heursure and rigrsure rules. As shown in the processing and analysis of simulated and experimental signals, denoising methods based on wavelet packet threshold have ability to depress the noise in laser Doppler signal and improve the precision of signal processing. Owing to its effectiveness and practicability, wavelet packet threshold denoising is a practical method for LDV signal processing. |
| format | Article |
| id | doaj-art-0265edaace21483dbc2eadce4d37ff43 |
| institution | OA Journals |
| issn | 1687-9384 1687-9392 |
| language | English |
| publishDate | 2019-01-01 |
| publisher | Wiley |
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| series | International Journal of Optics |
| spelling | doaj-art-0265edaace21483dbc2eadce4d37ff432025-08-20T02:01:50ZengWileyInternational Journal of Optics1687-93841687-93922019-01-01201910.1155/2019/10972921097292Laser Doppler Signal Denoising Based on Wavelet Packet Thresholding MethodDa Zhang0Ranglei Liu1College of Automation & Electronic Engineering, Qingdao University of Science and Technology, Qingdao 260061, ChinaCollege of Electromechanical Engineering, Qingdao University of Science and Technology, Qingdao 260061, ChinaIn laser Doppler velocimeter (LDV), calculation precision of Doppler shift is affected by noise contained in Doppler signal. In order to restrain the noise interference and improve the precision of signal processing, wavelet packet threshold denoising methods are proposed. Based on the analysis of Doppler signal, appropriate threshold function and decomposition layer number are selected. Heursure, sqtwolog, rigrsure, and minimaxi rules are adopted to get the thresholds. Processing results indicate that signal-to-noise ratio (SNR) and root mean square error (RMSE) of simulated signals with original SNR of 0 dB, 5 dB, and 10 dB in both low- and high-frequency ranges are significantly improved by wavelet packet threshold denoising. A double-beam and double-scattering LDV system is built in our laboratory. For measured signals obtained from the experimental system, the minimum relative error of denoised signal is only 0.079% (using minimaxi rule). The denoised waveforms of simulated and experimental signals are much more smooth and clear than that of original signals. Generally speaking, denoising effects of minimaxi and saqtwolog rules are better than those of heursure and rigrsure rules. As shown in the processing and analysis of simulated and experimental signals, denoising methods based on wavelet packet threshold have ability to depress the noise in laser Doppler signal and improve the precision of signal processing. Owing to its effectiveness and practicability, wavelet packet threshold denoising is a practical method for LDV signal processing.http://dx.doi.org/10.1155/2019/1097292 |
| spellingShingle | Da Zhang Ranglei Liu Laser Doppler Signal Denoising Based on Wavelet Packet Thresholding Method International Journal of Optics |
| title | Laser Doppler Signal Denoising Based on Wavelet Packet Thresholding Method |
| title_full | Laser Doppler Signal Denoising Based on Wavelet Packet Thresholding Method |
| title_fullStr | Laser Doppler Signal Denoising Based on Wavelet Packet Thresholding Method |
| title_full_unstemmed | Laser Doppler Signal Denoising Based on Wavelet Packet Thresholding Method |
| title_short | Laser Doppler Signal Denoising Based on Wavelet Packet Thresholding Method |
| title_sort | laser doppler signal denoising based on wavelet packet thresholding method |
| url | http://dx.doi.org/10.1155/2019/1097292 |
| work_keys_str_mv | AT dazhang laserdopplersignaldenoisingbasedonwaveletpacketthresholdingmethod AT rangleiliu laserdopplersignaldenoisingbasedonwaveletpacketthresholdingmethod |