Magnetic Anomaly Detection Method with Empirical Mode Decomposition and Minimum Entropy Feature
Journal Title: Applied Electromagnetics - Year 2023, Vol 11, Issue 1
Abstract
Abstract: Magnetic anomaly detection (MAD) is a passive method for airborne detection of subsurface objects. Light, radar and sound waves are unable to pass through the open air into the sea water environment and penetrate deep into the water, weaken or return to the air environment. On the other hand, the magnetic field force lines on this boundary are unchanged. MAD method is based on measuring the smallest changes or anomalies caused by the earth's magnetic field due to the passage of a ferro-magnetic object and the magnetic bipolar field generated around it, and especially in shallow waters, is one of the most efficient methods. Due to the rapid reduction of the magnetic field by increasing the distance, the magnetic disturbance generated by the magnetic target in the distance, usually buried in magnetic noise, in other words, the signal-to-noise ratio (SNR) decreases. In this paper, in order to improve the detection performance of magnetic impairment in low SNR, a hybrid method of MAD based on empirical mode decomposition (EMD) and minimal entropy method is proposed. In order to evaluate the performance of the method, an electronic measuring device has been constructed and magnetic data have been fieldly harvested from caspian sea in Anzali port area. These data impregnated with environmental magnetic noise have been investigated by entropy method. According to the entropy feature, magnetic anomaly is detected whenever entropy degrades below the defined threshold. In this way, the proposed method for detecting weak magnetic anomalies is also effective. The test results indicate a high probability of detection of the proposed method for low input SNR. Compared to the original signal SNR with -10 dB, the reconstructed signal SNR has improved to 8 dB. In addition, the total time of updating the parameters of the probability density function (PDF ), of noise is about 0.075s obtained.
Authors and Affiliations
Mehdi Jafri Moghaddam,Hamid Reza Khodadadi,Pourya etezadifar
Keywords
Related Articles
- EP ID EP730693
- DOI -
- Views 70
- Downloads 0
Theoretical study of the effect of the layer thickness on the sensitivity of tapered fiber optic sensors
In this paper, a comprehensive study was performed to investigate the effect of the absorbent layer thickness on the tapered fiber sensor sensitivity, which leads to the highest sensitivity for the sensor. For this purpo...
Review on In-service Efficiency Estimation of Three Phase Induction Motors
The standard methods for determining the efficiency of electric motors have been divided into two distinct categories; direct and indirect methods. Usually, it is difficult to prepare all necessary facilities and require...
Improving the model of Permanent Magnet Brushed DC Motor Used in Automotive Industry for Sensorless Speed Estimation
Permanent magnet brushed DC motors are widely used in the automotive industry due to their low cost and simple speed control. Sensorless speed and position estimation are interesting topics for car manufacturers and rese...
3D Simulation of Armature Motion in Electromagnetic Rail Launchers Using Finite Element Method
In the vast majority of previous research on electromagnetic rail launchers, either the two-dimensional analysis have been performed by finite element simulation, or in the case of three-dimensional study, armature and p...
A High-Resolution Active Microwave Sensor for Contactless Pressure Measurement
In this paper, an active contacless microwave pressure sensor with high-quality factor for harsh environment applications are presented. The proposed sensor operates at 1.2GHz and consists of two parts of a reader antenn...