Parameter Estimation of LFM Signal Based on Improved Fractional Fourier Transform

Given the current computational complexity and the unsatisfactory anti-noise performance of the linear frequency modulated (LFM) signal parameter estimation method, this paper proposes a rather innovative and efficient method based on improved fractional Fourier transform (FrFT). This method first obtains the energy distribution of time-frequency domain (TFD) through short-time Fourier transform (STFT), which is used to determine the order search range of FrFT. On the other hand, incoherent accumulation is also employed to improve the anti-noise performance under low signal-to-noise-ratio (SNR) environments. Extensive computer simulations verified that the algorithm displays a good anti-noise performance while reducing the amount of calculation.