Precise Magnetic Sensors for Navigation and Prospection

Abstract

Navigation, position tracking, search for unexploded ammunition, and geophysical prospection of magnetic or conducting ore are key applications where very small magnetic field signatures and field increments should be detected in the presence of the Earth's magnetic field, typically 50,000 nT. The industry calls for a new generation of portable vectorial magnetic sensors with a precision better than 0.1 nT. This error requirement includes not only sensor noise but also linearity, cross-field error, hysteresis, and perming and also temperature drift of the sensitivity and mainly the offset drift. For application on moving platform, the sensors should also have fast response. We will show that these requirements can be met only by fluxgate sensors. On the other hand, mass market requires cheap, low-power, and small magnetic sensors for portable gadgets; the typical application is compass in mobile phone, with precision of several degrees, corresponding to a 100-nT precision. For these applications, anisotropic magnetoresistance (AMR) sensor is dominant, while integrated fluxgates may penetrate the high-end market.

Microfluidic Synthesis, Control, and Sensing of Magnetic Nanoparticles: A Review

“…Magnetic sensors can detect and characterize magnetic nanoparticles in microfluidic chips. Magnetic field sensors and detectors are widely used in various applications, including industrial navigation sensors [ 116 , 117 , 118 ], storage technologies [ 119 , 120 , 121 ], and biosensors [ 122 , 123 , 124 ]. Various types of magnetic sensors, including superconducting quantum interference devices (SQUIDs), magnetoelectric sensors, anisotropic/giant/tunneling magnetoresistive sensors, magnetorelaxometry-based sensors, optically pumped sensors, Hall effect sensors, and so on are available [ 125 ].…”

Recent Progress of Fluxgate Magnetic Sensors: Basic Research and Application

“…Janosek et al developed the lowest noise fundamental-mode, orthogonal fluxgate magnetometer published so far [ 25 ]. Low noise magnetometers are important in many fields such as geomagnetic observatories, scientific experiments in aerospace, nondestructive testing and evaluation, and nanoparticle detection [ 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. According to the structure, fluxgate magnetometers can be classified into the parallel type and orthogonal type.…”

Magnetic Communication Using High-Sensitivity Magnetic Field Detectors

“…The sensors are very cheap and are mainly used as proximity indicators. They cannot be used for navigation purposes due to their low sensitivity [9]. Most properties of Hall effect sensors are suitable for magnetic communication systems.…”

“…This proposal promises many benefits that could lead to cheap and reliable system design, among other advantages. Precise magnetic detectors have been applied for localization and navigation purposes, see for example [8,9,10]. To the authors best knowledge, however, high-sensitivity magnetic field detectors have not been studied in the area of data communication.…”