Magnetic Anomaly Detection Utilizing Generalized Morse Wavelet and Morphological Filter

Magnetic anomaly detection (MAD) methods have been used for decades to detect and localize visually obscured ferromagnetic targets. In this work, an alternative MAD scheme based on the generalized Morse wavelet and morphological filter is proposed. First, the measured raw time sequence is converted into a time-scale representation, denoted as scalogram. Then an appropriate threshold is defined based on the histogram of the scalogram magnitude to filter out most geomagnetic noise and digitalize the scalogram as a binary image. Last, a proper two-dimensional structuring element is adopted for the morphological filter to reduce the residual noise. Experiments show that the proposed method achieves better performance than the traditional orthogonal basis functions method.