Abstract:

A parameters estimation method based on morphology operations is proposed to estimate the parameters of linear frequency modulation (LFM) signals, to resolve the contradiction between the estimation accuracy and the computation. According to the relationship between the parameters and the shape features of signal power spectra, the parameters of the LFM signals can be calculated. The experimental results demonstrate that the estimation accuracy of the chip rate and initial frequency can increase by about 2% and 4.5%, compared with the discrete spectrum correction method based on Radonambiguity transform (RAT) and fractional Fourier transform (FRFT) when signalto noise ratio (SNR) is -5dB, respectively. The root mean square errors (RMSE) of band width and pulse width estimation are less than 2. MHz and 0.025 μs, respectively. At the same time, the method can reduce the computational complexity by about 70% with the interpolation algorithms based on fractional Fourier transform (FRFT) when N≤4 096. And the simulation results prove the method has the advantage of high estimation accuracy and less computation.