Find in Library

In order to obtain reliable estimate of parameters, it is very important to protect the integrality of linear frequency modulation (LFM) signal. Therefore, in the practical LFM radar signal processing, the length of data frame is often greater than the pulse width (PW) of signal. In this condition, estimating the parameters by fractional Fourier transform (FrFT) will cause the signal to noise ratio (SNR) decrease. Aiming at this problem, we multiply the data frame by a Gaussian window to improve the SNR. Besides, for a further improvement of parameters estimation precision, a novel algorithm is derived via Lagrange interpolation polynomial, and we enhance the algorithm by a logarithmic transformation. Simulation results demonstrate that the derived algorithm significantly reduces the estimation errors of chirp-rate and initial frequency.