Finite rate of innovation sparse sampling for a binary frequency-coded ultrasonic signal  

基于有限新息率的二进制频率编码超声信号稀疏采样

作　　者：Song Shoupeng Chen Yiqian Xu Baowen Qiu Yue 宋寿鹏;陈仪倩;胥保文;邱越(江苏大学机械工程学院,镇江212013)

机构地区：[1]School of Mechanical Engineering,Jiangsu University,Zhenjiang 212013,China

出　　处：《Journal of Southeast University(English Edition)》2022年第1期27-35,共9页东南大学学报（英文版）

基　　金：The National Natural Science Foundation of China (No.51375217)。

摘　　要：To achieve sparse sampling on a coded ultrasonic signal,the finite rate of innovation(FRI)sparse sampling technique is proposed on a binary frequency-coded(BFC)ultrasonic signal.A framework of FRI-based sparse sampling for an ultrasonic signal pulse is presented.Differences between the pulse and the coded ultrasonic signal are analyzed,and a response mathematical model of the coded ultrasonic signal is established.A time-domain transform algorithm,called the high-order moment method,is applied to obtain a pulse stream signal to assist BFC ultrasonic signal sparse sampling.A sampling of the output signal with a uniform interval is then performed after modulating the pulse stream signal by a sampling kernel.FRI-based sparse sampling is performed using a self-made circuit on an aluminum alloy sample.Experimental results show that the sampling rate reduces to 0.5 MHz,which is at least 12.8 MHz in the Nyquist sampling mode.The echo peak amplitude and the time of flight are estimated from the sparse sampling data with maximum errors of 9.324%and 0.031%,respectively.This research can provide a theoretical basis and practical application reference for reducing the sampling rate and data volume in coded ultrasonic testing.为了实现编码超声信号的稀疏采样,提出了一种基于有限新息率的二进制频率编码超声信号稀疏采样方法.给出了脉冲类超声信号有限新息率稀疏采样的架构,分析了编码超声与脉冲超声信号的差异,建立了编码超声信号响应数学模型,采用高阶矩方法对编码回波信号进行了时域变换,获取了其脉冲流信号,经过采样核调制后实施等间隔稀疏采样,实现了编码超声的有限新息率稀疏采样.在此基础上,研制了硬件实现电路,并将该系统在铝合金样品试件上进行了稀疏采样测试,稀疏采样频率降至0.5 MHz(传统奈奎斯特采样频率至少为12.8 MHz),并能从稀疏采样数据中有效估计出回波信号的幅值和时延,最大估计误差分别为9.324%和0.031%.该研究为利用编码超声信号检测时降低采样速率和减少数据量提供了理论依据和实际应用参考.

关 键 词：coded ultrasonic signal finite rate of innovation high-order moment sparse sampling circuit implementation 

分 类 号：TB551[理学—物理]