Improvement of Range Resolution by Spectral Extrapolation
Improvement of Range Resolution by Spectral Extrapolation
复制标题
通过光谱外推提高距离分辨率
DOI：
10.1177/016173467900100202
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发表时间：
1979
影响因子：
2.3
通讯作者：
C. Chamzas
中科院分区：
文献类型：
--
作者：
A. Papoulis;C. Chamzas
在各种简化假设下，超声波对物质的询问中的反射信号y(T)是传输信号x(T)与函数h(T)的卷积，h(T)与介质在传播方向上的反射系数有关。函数h(T)原则上可以通过反卷积来确定。然而，由于x(T)的频谱X(ω)的频带B是有限的，所以不能可靠地找到B之外的h(T)的频率分量。本文提出了一种将X(ω)外推到B以外的方法。由此产生的分辨率的提高仅受噪声水平的限制。当h(T)是脉冲之和时，该方法特别有效。
Under various simplifying assumptions, the reflected signal y(t) in the interrogation of a substance by an ultrasonic wave is a convolution of the transmitted signal x(t) with a function h(t) that is related to the reflection coefficient of the medium in the direction of propagation. The function h(t) can, in principle, be determined by deconvolution. However, since the band B of the spectrum X(ω) of x(t) is finite, the frequency components of h(t) outside B cannot be found reliably. In this paper, a method is presented for extrapolating X(ω) beyond B. The resulting increase in resolution is limited only by the level of noise. The method is particularly effective if h(t) is a sum of impulses.