Broadband ultrasound signals will produce distortion in viscoacoustic medium, which may influence the accuracy of time-of-flight (TOF) measurement. Under the condition of single-frequency acoustic source, the wave pro...Broadband ultrasound signals will produce distortion in viscoacoustic medium, which may influence the accuracy of time-of-flight (TOF) measurement. Under the condition of single-frequency acoustic source, the wave propagation process in viscoacoustic medium was analyzed and an approximate solution of the wave propagation was given. Instances of broadband ultrasound were analyzed and simulated based on the single-frequency results. A single-frequency matching pursuits (SFMP) algorithm was then introduced to solve the waveform distortion problem. Time-frequency decomposition was applied to extracting the single-frequency compositions from broadband ultrasound signals, and then these compositions were sent to the matching pursuits (MP) algorithm for calculating the TOF parameters. Compared with the broadband signals, the shapes of extracted single-frequency signals change more slightly as distance and attenuation coefficient increase. The residuals of SFMP were far less than those of MP algorithm. Experimental results show that the SFMP algorithm is able to eliminate waveform distortion of broadband ultrasound in viscoacoustic medium, which helps improve the accuracy of TOF measurement.展开更多
Orthogonal matching pursuit （OMP） algorithm is an efficient method for the recovery of a sparse signal in compressed sensing, due to its ease implementation and low complexity. In this paper, the robustness of the O...Orthogonal matching pursuit （OMP） algorithm is an efficient method for the recovery of a sparse signal in compressed sensing, due to its ease implementation and low complexity. In this paper, the robustness of the OMP algorithm under the restricted isometry property （RIP） is presented. It is shown that 5K＋V/KOK,1 〈 1 is sufficient for the OMP algorithm to recover exactly the support of arbitrary /（-sparse signal if its nonzero components are large enough for both 12 bounded and lz~ bounded noises.展开更多
This paper describes a full waveform sampling LiDAR system applying stripe principle. A kind of denoising method based on edge detection of original stripe signal is proposed. This method is compared with other denois...This paper describes a full waveform sampling LiDAR system applying stripe principle. A kind of denoising method based on edge detection of original stripe signal is proposed. This method is compared with other denoising methods, such as Wiener filtering, mean filtering and median filtering. It is found that the proposed denoising method is much more effective for dealing with the waveform signals.展开更多
基金Supported by National Natural Science Foundation of China (No.30800240 and No.60901043)
文摘Broadband ultrasound signals will produce distortion in viscoacoustic medium, which may influence the accuracy of time-of-flight (TOF) measurement. Under the condition of single-frequency acoustic source, the wave propagation process in viscoacoustic medium was analyzed and an approximate solution of the wave propagation was given. Instances of broadband ultrasound were analyzed and simulated based on the single-frequency results. A single-frequency matching pursuits (SFMP) algorithm was then introduced to solve the waveform distortion problem. Time-frequency decomposition was applied to extracting the single-frequency compositions from broadband ultrasound signals, and then these compositions were sent to the matching pursuits (MP) algorithm for calculating the TOF parameters. Compared with the broadband signals, the shapes of extracted single-frequency signals change more slightly as distance and attenuation coefficient increase. The residuals of SFMP were far less than those of MP algorithm. Experimental results show that the SFMP algorithm is able to eliminate waveform distortion of broadband ultrasound in viscoacoustic medium, which helps improve the accuracy of TOF measurement.
基金supported by National Natural Science Foundation of China(Grant Nos.11271060,U0935004,U1135003,11071031,11290143 and 11101096)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry,National Engineering Research Center of Digital Lifethe Guangdong Natural Science Foundation(Grant No.S2012010010376)
文摘Orthogonal matching pursuit （OMP） algorithm is an efficient method for the recovery of a sparse signal in compressed sensing, due to its ease implementation and low complexity. In this paper, the robustness of the OMP algorithm under the restricted isometry property （RIP） is presented. It is shown that 5K＋V/KOK,1 〈 1 is sufficient for the OMP algorithm to recover exactly the support of arbitrary /（-sparse signal if its nonzero components are large enough for both 12 bounded and lz~ bounded noises.
基金supported by the National Natural Science Foundation of China(No.11004042)the National Key Scientific Instrument and Equipment Development Projects(No.2012YQ040164)the Science Funds of Heilongjiang Province(No.F2016015)
文摘This paper describes a full waveform sampling LiDAR system applying stripe principle. A kind of denoising method based on edge detection of original stripe signal is proposed. This method is compared with other denoising methods, such as Wiener filtering, mean filtering and median filtering. It is found that the proposed denoising method is much more effective for dealing with the waveform signals.
