Estimation method of LFM signal parameters based on efficient FrFT and iterative interpolation

Aiming at the scenario of reconnaissance receiver estimating LFM radar signal modulation parameters under low signalto- noise ratio, an efficient signal parameter estimation method based on FrFT and iterative interpolation is proposed. Firstly, the reconnaissance receiver uses the efficient FrFT algorithm to estimate the optimal rotation angle of different subcarriers, and then uses the fractional autocorrelation iterative interpolation method to continue to reduce the error between the optimal rotation angle estimate and the true value, and obtains a more accurate rotation angle estimate after finite iterations. The proposed method has low computational complexity, which is conducive to the rapid estimation of radar signal parameters by the reconnaissance receiver, and has good estimation performance in the low signal-to-noise ratio environment, which provides a certain basis for the engineering implementation.