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Auerbach, E., Leder, N., Gider, S., Suess, D., Arthaber, H..  2017.  Characterization of dynamic nonlinear effects in MTJ-based magnetic sensors. 2017 Integrated Nonlinear Microwave and Millimetre-wave Circuits Workshop (INMMiC). :1–3.

The MgO-based magnetic tunnel junction (MTJ) is the basis of modern hard disk drives' magnetic read sensors. Within its operating bandwidth, the sensor's performance is significantly affected by nonlinear and oscillating behavior arising from the MTJ's magnetization dynamics at microwave frequencies. Static I-V curve measurements are commonly used to characterize sensor's nonlinear effects. Unfortunately, these do not sufficiently capture the MTJ's magnetization dynamics. In this paper, we demonstrate the use of the two-tone measurement technique for full treatment of the sensor's nonlinear effects in conjunction with dynamic ones. This approach is new in the field of magnetism and magnetic materials, and it has its challenges due to the nature of the device. Nevertheless, the experimental results demonstrate how the two-tone measurement technique can be used to characterize magnetic sensor nonlinear properties.

D
Moritz, Pierre, Mathieu, Fabrice, Bourrier, David, Saya, Daisuke, Blon, Thomas, Hasselbach, Klaus, Kramer, Roman, Nicu, Liviu, Lacroix, Lise-Marie, Viau, Guillaume et al..  2019.  Development Of Micro-Magnets For The Electromagnetic Transduction Of MEMS. 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems Eurosensors XXXIII (TRANSDUCERS EUROSENSORS XXXIII). :1748–1751.
This paper presents a new class of high-performance permanent micro-magnets based on the controlled assembly of cobalt nanorods for the electromagnetic transduction of MEMS. Micromagnets are fabricated using a low temperature fabrication process that yields a dense material exhibiting high coercive field and remanence to saturation magnetization ratio. The cartography of the magnetic induction produced by the sub-millimeter size magnets was obtained using a scanning Hall effect micro-probe microscope. Silicon microcantilevers placed in the vicinity of these magnets were successfully actuated using the Lorentz force with low currents. The good signal to noise ratio measured at resonance demonstrates the potentiality of these nanostructured micro-magnets.
H
Ferraris, L., Franchini, F., Pošković, E..  2016.  Hybrid magnetic composite (HMC) materials for sensor applications. 2016 IEEE Sensors Applications Symposium (SAS). :1–6.

Several applications adopt electromagnetic sensors, that base their principle on the presence of magnets realized with specific magnetic materials that show a rather high remanence, but low coercivity. This work concerns the production, analysis and characterization of hybrid composite materials, with the use of metal powders, which aim to reach those specific properties. In order to obtain the best coercivity and remanence characteristics various "recipes" have been used with different percentages of soft and hard magnetic materials, bonded together by a plastic binder. The goal was to find out the interdependence between the magnetic powder composition and the characteristics of the final material. Soft magnetic material (special Fe powder) has been used to obtain a low coercivity value, while hard materials were primarily used for maintaining a good induction remanence; by increasing the soft proportion a higher magnetic permeability has been also obtained. All the selected materials have been characterized and then tested; in order to verify the validity of the proposed materials two practical tests have been performed. Special magnets have been realized for a comparison with original ones (AlNiCo and ferrite) for two experimental cases: the first is consisting in an encoder realized through a toothed wheel, the second regards the special system used for the electric guitars.

M
Gao, J., Wang, J., Zhang, L., Yu, Q., Huang, Y., Shen, Y..  2019.  Magnetic Signature Analysis for Smart Security System Based on TMR Magnetic Sensor Array. IEEE Sensors Journal. :1–1.

This paper presents a novel low power security system based on magnetic anomaly detection by using Tunneling Magnetoresistance (TMR) magnetic sensors. In this work, a smart light has been developed, which consists of TMR sensors array, detection circuits, a micro-controller and a battery. Taking the advantage of low power consumption of TMR magnetic sensors, the smart light powered by Li-ion battery can work for several months. Power Spectrum Density of the obtained signal was analyzed to reject background noise and improve the signal to noise ratio effectively by 1.3 dB, which represented a 30% detection range improvement. Also, by sending the signals to PC, the magnetic fingerprints of the objects have been configured clearly. In addition, the quick scan measurement has been also performed to demonstrate that the system can discriminate the multiple objects with 30 cm separation. Since the whole system was compact and portable, it can be used for security check at office, meeting room or other private places without attracting any attention. Moreover, it is promising to integrate multiply such systems together to achieve a wireless security network in large-scale monitoring.

Kroon, Martin, Bongers, Ed, Bubeck, Klaus.  2019.  Magnetic tests and analysis of JUICE solar array. 2019 European Space Power Conference (ESPC). :1–5.
Very sensitive magnetic instruments on the JUICE spacecraft require an extremely low magnetic field emission of the various subsystems. The JUICE solar array includes a photovoltaic assembly and various mechanisms with a magnetic signature. The design of the photovoltaic assembly has been optimised not only with respect to magnetic moment, but also with respect to the emitted magnetic field, by applying the so-called back-wiring technique, alternating string polarity etc. The remanent magnetic field of the mechanisms (hinges, eddy-current damper, hold-down & release mechanism) was tested including a process for demagnetisation. In addition, the temperature coefficient for the magnetic moment was measured, down to the operational temperature of -130°C. The eddy-current damper was also subjected to a field-induced magnetisation test. All the contributors were included in a model to calculate the magnetic field at the instrument location.
Beran, P., Klöhn, M., Hohe, H..  2019.  Measurement Characteristics of Different Integrated Three-Dimensional Magnetic Field Sensors. IEEE Magnetics Letters. 10:1–5.
Datasheets of different commercially available integrated sensors for vector measurements of magnetic fields provide typical specifications, such as measurement range, sampling rate, resolution, and noise. Other characteristics of interest, such as linearity, cross-sensitivity, remanent magnetization, and drifts over temperature, are mostly missing. This letter presents testing results of those characteristics of integrated three-dimensional (3-D) sensors working with different sensor principles and technologies in a reproducible measuring process. The sensors are exposed to temperatures from -20 °C to 80 °C and are cycled in hysteresis loops in fields up to 2.5 mT. For applying high-accuracy magnetic fields, a calibrated 3-D Helmholtz coil setup is used. Commercially available integrated 3-D magnetic field sensors are put in operation on a printed circuit board using nonmagnetic passive components. All sensors are configured for best measurement accuracy according to their data-sheets. The results show that sensors based on anisotropic magnetoresistance have high accuracy and low offsets yet also a high degree of nonlinearity. Hall-based sensors show good linearity but also high cross-sensitivity. A magnetic remanence appears for Hall-based sensors with integrated magnetic concentrators as well as for sensors using anisotropic magnetoresistance. Nearly all sensors show remaining drifts over temperature regarding offset and sensitivity up to several percentages.
S
Singh, S., Saini, H. S..  2018.  Security approaches for data aggregation in Wireless Sensor Networks against Sybil Attack. 2018 Second International Conference on Inventive Communication and Computational Technologies (ICICCT). :190–193.
A wireless sensor network consists of many important elements like Sensors, Bass station and User. A Sensor can measure many non electrical quantities like pressure, temperature, sound, etc and transmit this information to the base station by using internal transreceiver. A security of this transmitted data is very important as the data may contain important information. As wireless sensor network have many application in the military and civil domains so security of wireless sensor network become a critical concern. A Sybil attack is one of critical attack which can affect the routing protocols, fair resourse allocation, data aggregation and misbehavior detection parameters of network. A number of detection techniques to detect Sybil nodes have already designed to overcome the Sybil attack. Out of all the techniques few techniques which can improve the true detection rate and reduce false detection rate are discussed in this paper.
Pawlenka, T., Škuta, J..  2018.  Security system based on microcontrollers. 2018 19th International Carpathian Control Conference (ICCC). :344–347.
The article describes design and realization of security system based on single-chip microcontrollers. System includes sensor modules for unauthorized entrance detection based on magnetic contact, measuring carbon monoxide level, movement detection and measuring temperature and humidity. System also includes control unit, control panel and development board Arduino with ethernet interface connected for web server implementation.