Spatial focusing algorithm for source enumeration with rotating uniform circular sonar arrays

• Published in: IET radar, sonar & navigation sonar & navigation, 2023-12, Vol.17 (12), p.1760-1767
• Main Authors: Liang, Guolong, Liu, Guolong, Hao, Yu, Zou, Nan, Zhao, Chunpeng
• Format: Article
• Language: English
• Subjects: sensor arrays; signal sources; sonar arrays; sonar detection
• ISSN: 1751-8784; 1751-8792
• DOI: 10.1049/rsn2.12462

Source enumeration with large snapshots is feasible for a static uniform circular sonar array (UCSA). However, the dimension of the signal subspace in the array coordinate system exceeds the number of signal sources due to the rotation of the UCSA, which makes standard source enumeration ineffective. To address this issue, a spatial focusing approach for source enumeration with rotating UCSAs is presented. The approach is based on the concept of phase‐mode excitation and makes use of the UCSA heading information to achieve spatial focusing. The proposed algorithm provides reliable source enumeration with a high signal‐to‐noise ratio (SNR) when compared to the previous signal‐subspace transformation (SST) method. Simulations demonstrate that the proposed algorithm outperforms the other three methods in the conditions of a low SNR and a small angular separation. A phase mode excitation‐based spatial focusing algorithm to deal with the challenge of source enumeration using rotating uniform circular arrays is proposed. The algorithm is based on the idea of phase‐mode excitation, which allows for source enumeration with large snapshots.