A method for locating magnetic targets using the total geomagnetic field gradient array

Abstract

The present invention belongs to the technical field of terrestrial magnetism detection, and especially relates to a method for magnetic object location through adoption of a terrestrial magnetism total field gradient array. The method comprises the following steps of: constructing a sensor array formed by seven scalar magnetic sensors; according to the sensor array, based on a magnetic dipole far-field model, and establishing a relation of the terrestrial magnetism total field gradient and magnetic object position coordinates and magnetic moment vectors, wherein the relation of the terrestrial magnetism total field gradient and magnetic object position coordinates and magnetic moment vectors employs matrix transformation to perform elimination reduction of solution parameters to three; and establishing a fitness function, and employing a particle swarm optimization to calculate the minimum value of the fitness function to solve a target position. The method is relatively high in resolution ratio, can perform location of a flux weakening target, is long in location distance and wide in range, only needs to avoid the dead zone direction of an optical pump magnetometer when rapid solution and location equation measurement are performed with no need for real-time measurement and compensation of the attribute of each sensor, and is simple and rapid.

Description

technical field [0001] The invention belongs to the technical field of geomagnetic detection, and in particular relates to a method for locating a magnetic target by using a geomagnetic total field gradient array. Background technique [0002] The geomagnetic field is a natural physical field of the earth. It has various origins and is formed by the superposition of magnetic field components with different changing laws. According to the location of the field source, the geomagnetic field can be divided into internal source field and external source field. If we consider the changing characteristics of the geomagnetic field with time, the geomagnetic field that changes rapidly with time becomes the changing magnetic field of the earth, and the geomagnetic field that changes slowly or basically remains unchanged with time becomes the stable magnetic field of the earth. [0003] The magnetic field generated by a magnetic target will lead to changes in the distribution of the ...

AI Technical Summary

Problems solved by technology

Therefore, it is necessary and difficult to compensate the influence of the attitude change of the vector magnetic sensor on the measurement in real time.

In general, the resolution of common vector magnetic sensors (such as ordinary fluxgate magnetometers) on the market is relatively low (compared to scalar optical pump magnetometers), so the target positioning distance based on vector measurement cannot be too long, and the target magnetic moment not too small

[0005] To sum up, there are problems such as low resolution, complex installation and use, short detection distance, high requirements for detected objects, and small application range in the existing technology.

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