Multi-channel frequency domain adaptive line spectrum enhancement technology based on line array

Abstract

For the issue of weak line spectrum target autonomous detection of unmanned platform in complex underwater environments, the multi-channel frequency domain adaptive line spectrum enhancement technology base on line array is proposed. This paper uses the relationship between coherence properties of line spectrum signals and the same delays of two adjacent array elements, and after averaging the cross-spectrum of two adjacent array elements, enhances the spectrum of the acquired signals. The Inverse Fourier Transform is taken as input signals of frequency domain adaptive filter, and to a certain extent, the SNR of the input signals is improved, and the processing gain is improved. The simulation result shows that when the input SNR is -21dB, the processing gain of this algorithm is 10.3dB higher than that of the STALE algorithm. The simulation and sea trial data indicate that the performance of this algorithm is greatly improved than that of STALE algorithm. Compared with the existing line spectrum target detection algorithm based on line spectrum characteristics, the algorithm in this Paper has lower requirements on SNR, and in complex situations such as the situations of multi-target and multi-line spectrum, etc., has better line spectrum target detection performance.