超声回波参数估计的初值选取方法

针对超声回波参数估计中,初值随机选取带来的收敛速度慢,搜索效率低,易受噪声影响等问题,对回波参数估计的初值选取进行了探讨。理论上研究了超声回波信号的包络和能量与信号参数的关系,阐明了从信号自身选取参数初值的可行性。在此基础上,利用希尔伯特变换和傅里叶变换提取有效信息,为回波参数估计提供合适的初值,从而减少估计过程的迭代次数、提高参数估计速度。实验结果表明,与传统参数估计方法相比,该方法在不同信噪比情况下都可获得较高的估计精度,而且参数估计的收敛速度较快。 

Selection of initial values for ultrasonic echo parameter estimation

In the estimation of ultrasonic echo parameters,initial values are usually randomly selected.This approach makes the algorithm slow in convergence,low in search efficiency,and susceptible to noise and other issues.The selection of the initial value of the echo parameter estimation is discussed.The relationship between the envelope and energy of the ultrasonic echo signal and the signal parameters is theoretically analyzed,and the feasibility of selecting the initial value of the signal from the signal itself is clarified.On this basis,the effective information is extracted using Hilbert transform and Fourier transform to provide suitable initial values for echo parameter estimation,thereby reducing the number of iterations of the estimation process and increasing the parameter estimation speed.Experimental results show that compared with the traditional parameter estimation methods,this method can obtain higher estimation accuracy under different signal-to-noise ratios,and the convergence rate of parameter estimation is faster.