为更准确且简洁地表达超宽带的线性调频(LFM)信号的非线性相位,文中采用一种高阶模糊函数,而不是经典的泰勒展开来表达非线性相位多项式,并用高阶模糊函数(HAF)法估计非线性相位多项式系数。针对因目标延时不同导致的非线性程度不同的问题,采用了一种频域校正法补偿回波的非线性相位,一次性完成不同距离目标的一维距离像聚焦,无需对不同距离目标分别进行校正处理,算法效率大大提高。

In order to express the non-linearity of ultrawideband linear frequency modulation (LFM) signal more accurately and concisely, a polynomial expression based on higher-order ambiguity function (HAF) rather than classical Taylor expansion is used to express the nonlinear phase polynomial, and the HAF method is used to estimate the parameters of the non-linear phase polynomial coefficients. In order to solve the problem of different degree of nonlinearity caused by different target delay, a frequency domain correction method is used to compensate the non-linear phase, and one-dimensional range profile of different range targets is refocused at one time. Different range targets don′t need to be corrected separately, so the efficiency of the algorithm is greatly improved.

TN957.51