本文给出了连续复线性调频(LFM)信号Radon-Wigner变换(RWT)、Wigner-Hough变换(WHT)、分数阶傅立叶变换(FrFT)、解线调方法(Dechirp)和最大似然(ML)方法的相互转换关系。给出了参数估计的最佳表述及其离散形式,省略包含调频率的表达式系数,将RWT、WHT、FrFT和Dechirp和ML方法用统一表达式表述。几种方法的离散LFM信号参数估计均可以用ML或去斜方法实现,并采用FFT方法提高运算速度,因此最佳快速算法的计算量和估计性能是相同的。本文对于这几种参数估计方法的快速算法和估计性能研究具有指导意义。
The reciprocal transforming relationship of FM (Frequency Modulation) parameters estimation methods for continuous complex LFM signal, including Radon-Wigner transform ( RWT), Wigner-Hough transform ( WHT), Fractional Fourier transform ( FrFT), Dechirp and Maximum Likelihood ( ML), is given in this paper. The optimal expression and discrete form of FM parameters esti- mation is proposed, which omits the coefficient of chirp rate, and those methods are given in uniform expression. For discrete sampling signal, those methods can be carried out via ML or Dechirp, and the fast Fourier transform (FFT) can be utilized to improve the operation speed. The operation amount and estimation performance are uniform for those methods via the optimal algorithm. The paper can be used to help the study of the fast algorithm and estimation performance analysis of those methods of FM parameters estimation.