Abstract：A new method is proposed in this paper to accomplish the carrier frequency estimation of non- cooperative underwater acoustic DSSS-BPSK signal. The carrier frequency estimated using the method is accurate even under low-CNR and signal distortion conditions. A rough estimation of the carrier frequency is first made through gravity method. With the concave point characteristic of the signal power spectrum envelope at the carrier frequency, a more precise carrier frequency is then estimated by searching the local minimum of the power spectrum envelope in the frequency neighborhood of the rough estimation. Monte Carlo simulations of the method are in accord with theoretical analysis. Results of oceanic experimental data test also verify the effectiveness feasibility and practicality of the method for its low complexity and robustness under low-CNR and signal distortion conditions.
2009, Vol. 31 
