Coherent Accumulation Algorithm Based Multilevel Switching Adaptive Line Enhancer

摘要

For effectively extracting line spectrum signals from non-Gaussian noise, a Coherent Accumulation algorithm based Two-path Three-stage Switching Adaptive Line Enhancer(CATTSALE) was established. In the CATTSALE, one path is composed of a Fourth order cumulant Variable step size Sign Coherent Accumulation algorithm based Adaptive Line Enhancer (FVSCAALE), a Least mean square Coherent Accumulation based Adaptive Line Enhancer(LCAALE), and a Short-term Correlation Coherent Accumulation based Adaptive Line Enhancer(SCCAALE), whereas the other one is made up of the FVSCAALE and two SCCAALEs. Two-path may be switched by the on-off in the second level of the CATTSALE to obtain the much better effect of enhancing line spectra. Simulation tests with real data of the underwater moving target-radiated noise were carried out. The results have shown that the CATTSALE has immunity to Gaussian noise and that better ability to suppress non-Gaussian noise and to trace time-varying signals and outperforms the single LCAALE, the FVSCAALE, and the SCCAALE.