CAJ | 학술논문

在满足对称分布的海洋噪声场中，为提高低信噪比条件下目标方位估计性能，提出一种重构信号协方差矩阵的MUSIC算法。利用数据协方差矩阵虚部与对称噪声无关的性质，根据协方差矩阵虚部和虚部MUSIC算法的预估角重构出信号协方差矩阵，在此基础上实现MUSIC算法。仿真结果表明，所提算法相比常规MUSIC算法能有效降低对称噪声的影响，提高方位估计性能，并避免双边谱的出现，有更高的分辨率和更低的分辨门限。还研究了协方差矩阵的Toeplitz修正处理对于MUSIC类算法的改善作用。仿真表明，Toeplitz修正处理能显著提高MUSIC类算法的分辨性能。
재만족대칭분포적해양조성장중，위제고저신조비조건하목표방위고계성능，제출일충중구신호협방차구진적MUSIC산법。이용수거협방차구진허부여대칭조성무관적성질，근거협방차구진허부화허부MUSIC산법적예고각중구출신호협방차구진，재차기출상실현MUSIC산법。방진결과표명，소제산법상비상규MUSIC산법능유효강저대칭조성적영향，제고방위고계성능，병피면쌍변보적출현，유경고적분변솔화경저적분변문한。환연구료협방차구진적Toeplitz수정처리대우MUSIC류산법적개선작용。방진표명，Toeplitz수정처리능현저제고MUSIC류산법적분변성능。
In the symmetrical distribution ocean noise field, in order to improve the direction-of-arrival (DOA) estima-tion performance in low signal-to-noise (SNR) conditions, a novel MUSIC algorithm that reconstructs the signal cova-riance matrix is presented. Based on the properties that the image part of data covariance matrix has no relation with the symmetric noise, the signal covariance matrix is reconstructed by using the image part of data covariance matrix and the DOA which is estimated by Image-MUSIC algorithm. Thus, the MUSIC algorithm is implemented. Simulation results show that the new algorithm effectively reduces the influence of symmetrical noise on DOA estimation and avoids bi-lateral spectrum arising, moreover the algorithm achieves higher resolution and lower resolution threshold in low SNR cases. Covariance matrix’s Toeplitz modification that aims to improve the DOA estimation performance of MUSIC algorithm has also been studied, and simulation results show that the resolution of MUSIC algorithm is improved sig-nificantly.