Research on the Combined Detection of Magnetic Anomaly and Shaft‐Rate Magnetic Field Signals

ABSTRACT Due to the stable propagation of magnetic signals in ocean and air, magnetic detection technology has become an effective means for nonacoustic detection. The magnetic anomaly signal and shaft‐rate magnetic signal radiated by underwater vehicles are currently the most effective magnetic detection signals. Existing magnetic detection methods primarily focus on studying either magnetic anomaly signal or shaft‐rate magnetic signal. However, since a target can generate both of these magnetic signals simultaneously, detecting one type may lead to the neglect of the other, reducing detection accuracy. To overcome the limitations of existing technologies, this paper presents a combined detection method for magnetic anomaly and shaft‐rate magnetic signals. The detection process is divided into magnetic anomaly signal detection based on orthogonal basis function (OBF) and shaft‐rate magnetic signal detection based on adaptive line spectrum enhancement (ALE). Especially for the detection of magnetic anomaly signal, this paper proposes a preprocessing method based on the LOESS smoothing technique, utilising noise characteristics, and combines it with the CFAR criterion for decision‐making. This approach significantly improves the detection accuracy of the magnetic anomaly signal. Finally, the simulation and experimental results show that combining magnetic anomaly and shaft‐rate magnetic signals for combined detection can effectively improve the detection accuracy.