An estimation algorithm of chirp based on fractional fourier transform and frequency domain differential

By combining the FFT, FRFT and frequency domain differential, this paper proposes an efficient algorithm which can be used to estimate the value of chirp ratio of mono-component LFM signal approximately. The fundamental idea is to differentiate in frequency domain for highlighting lateral peaks. Then, the chirp ratio can be estimate approximately. Using FRFT to search the peak in a range of angle plane, the accurate parameters could be determined by corresponding rotation angle. Theoretic deduction and computer simulations prove the proposed algorithm can lock the scope of error effectively and anti-noise performance is well. Computational cost can reduce remarkable with the same precision.