Estimation of Underwater Acoustic Doppler Factor and time Delay based on time-frequency Analysis of multi-component LFM Signals
The use of the multicomponent Linear Frequency Modulated (LFM) signals for estimating the underwater acoustic Doppler factor and time delay estimation is increasingly common in the practical process.An adaptive chirp-mode-decomposition algorithm based on incomplete residual and ridge segment matching is proposed to solve the problem of inaccurate parameter estimation for multicomponent LFM with cross-terms in the time–frequency domain. The incomplete residual function is used to retain part of the time-frequency information at the intersection point, and the ridge segment matching method is used to provide a more accurate time-frequency ridge, improving the estimation accuracy of the frequency modulation slope and starting frequency of each component of LFM signal. A combination of these two estimators provides the algorithm for estimating the Doppler factor and time delay. The results showed the proposed method effectively solves the estimation error induced by the break of cross-interval, compared with the existing mode-decomposition algorithms. The accuracy of the proposed method for estimating the Doppler factor and time delay is better than that of the existing methods in underwater acoustic multipath propagation.
万方数据
维普
