Electromagnetic Field Probes Research Articles

Enhanced Electromagnetic Near Field Probe for Diagnosis and Materials Characterization

Enhanced Electromagnetic Near Field Probe for Diagnosis and Materials Characterization

A Detection method of electromagnetic analysis attacks based on change in amplitude of noise around integrated circuits

Electromagnetic analysis (EMA) attacks are a type of side-channel attacks that can be performed without opening or modifying a cryptographic module. In this study, we propose a detection method for the measurement of side-channel information, which is performed at the preliminary stage of the analysis of the target device as a countermeasure against EMA attacks performed near integrated circuits (ICs) with cryptographic modules. The presence of an electromagnetic (EM) field probe is detected by analyzing the sampling background noise around the IC using an analog-to-digital converter (ADC) inside the IC and by observing any changes in the EM environment. The proposed method can effectively detect a probe placed 5 cm from the IC package.

Discharge and electromagnetic radiation behind the hole of simulated charging satellite surface under impact

To evaluate the threat of the impact of micrometeoroids and orbital debris on the satellite, we designed an unequal potential charging device on the satellite surface in the ground experiment. The unequal potential charging device is placed on a metal box to simulate the satellite shell. A small hole is opened on the metal box to study the coupling effect between the electromagnetic pulse generated by the impact and the small hole. We recorded the impact experiment's discharge current and voltage curves and detected the electromagnetic and plasma signals on both sides of the hole. The experimental results show that the plasma entering the metal box through the small hole will release the voltage difference inside and outside the metal box and cause the discharge. The electromagnetic field probe in the metal box also detected the electromagnetic radiation signal of 20∼100 MHz.

Near-Field Precision Measurement System of High-Density Integrated Module

An automatic near-field precision measurement system was proposed in this article. The work was mainly focused on the hardware structure design of the near-field precision measurement system and the software development of the upper computer. At the same time, the electromagnetic field probes used in the system were selected and introduced. The near-field precision measurement system was composed of an upper computer control part, motion controller, power amplifier module, three-axes mechanical arms, spectrum analyzer, and near-field probes. Three-axes mechanical arm, multi-degree-of-freedom fixture, and electromagnetic field probe cooperate with each other for near-field measurement. The electromagnetic radiation emission of high-density integrated module and liquid crystal display (LCD)-printed circuit board (PCB) of laptop computer were measured. According to the measured data, the visual field distribution map was generated, and the measured results were analyzed. Compared with manual measurement method and commercial electromagnetic compatibility (EMC) scanners, the near-field precision measurement system has more accurate measurement results and can accurately locate the noise source.

An ultra wideband-high spatial resolution-compact electric field sensor based on Lab-on-Fiber technology

Non-intrusive, wide bandwidth and spatial resolution are terms often heard in electric field sensing. Despite of the fact that conventional electromagnetic field probes (EMF) can exhibit notable functional performances, they fail in terms of perturbation of the E-field due to their loaded metallic structure. In addition, even though electro-optical technology offers an alternative, it requires large interaction lenghts which severely limit the sensing performances in terms of bandwidth and spatial resolution. Here, we focus on miniaturizing the interaction volume, photon lifetime and device footprint by taking advantage of the combination of lithium niobate (LN), Lab-on-Fiber technologies and photonic crystals (PhC). We demonstrate the operation of an all-dielectric E-field sensor whose ultra-compact footprint is inscribed in a 125 μm-diameter circle with an interaction area smaller than 19 μm × 19 μm and light propagation length of 700 nm. This submicrometer length provides outstanding bandwidth flatness, in addition to be promising for frequency detection beyond the THz. Moreover, the minituarization also provides unique features such as spatial resolution under 10 μm and minimal perturbation to the E-field, accompanied by great linearity with respect to the E-field strength. All these specifications, summarized to the high versatibility of Lab-on-Fiber technology, lead to a revolutionary and novel fibered E-field sensor which can be adapted to a broad range of applications in the fields of telecommunications, health and military.

Analysis of Omni-directivity Error of Electromagnetic Field Probe using Isotropic Antenna

Abstract This manuscript analyzes the omni-directivity error of an electromagnetic field (EM) probe and its dependence on frequency. The global directional characteristic of a whole EM probe consists of three independent directional characteristics of EM sensors - one for each coordinate. The shape of particular directional characteristics is frequency dependent and so is the shape of the whole EM probe’s global directional characteristic. This results in systematic error induced in the measurement of EM fields. This manuscript also contains quantitative formulation of such errors caused by the shape change of directional characteristics for different types of sensors depending on frequency and their mutual arrangement.

Measurement of the electric field intensity in the near-field region with proposed electromagnetic field probe

This paper deals with a measurement of the electric field intensity in the near field region with proposed autonomous electromagnetic (EM) field probe. This probe is specially designed to measure in the near distance from the sources of the EM field. The output from the probe is a voltage corresponding to the measured component of the electric field intensity. At the end we compared results from measurement of the components of the electric field intensity with the results from simulation based on the numerical method. Streszczenie. Artykul dotyczy pomiaru natezenia pola elektrycznego w strefie bliskiej za pomocą zaproponowanej autonomicznej sondy pola elektromagnetycznego (EM). Sonda ta zostala zaprojektowana specjalnie do pomiaru w strefie bliskiej źrodla pola EM. Na wyjściu sondy otrzymuje sie napiecie odpowiadające mierzonemu komponentowi natezenia pola elektrycznego. W artykule porownano rezultaty pomiarow komponentow natezenia pola elektrycznego z wynikami symulacji prowadzonych z wykorzystaniem metod numerycznych. (Pomiar natezenia pola elektrycznego w strefie bliskiej za pomocą proponowanej sondy pola elektrycznego).

Optymalizacja metodyki pomiaru wieloczęstotliwościowego pola elektromagnetycznego stacji bazowych telefonii komórkowej

This paper presents the characteristics of the mobile phone base station (BS) as an electromagnetic field (EMF) source. The most common system configurations with their construction are described. The parameters of radiated EMF in the context of the access to methods and other parameters of the radio transmission are discussed. Attention was also paid to antennas that are used in this technology. The influence of individual components of a multi-frequency EMF, most commonly found in the BS surroundings, on the resultant EMF strength value indicated by popular broadband EMF meters was analyzed. The examples of metrological characteristics of the most common EMF probes and 2 measurement scenarios of the multisystem base station, with and without microwave relays, are shown. The presented method for measuring the multi-frequency EMF using 2 broadband probes allows for the significant minimization of measurement uncertainty. Equations and formulas that can be used to calculate the actual EMF intensity from multi-frequency sources are shown. They have been verified in the laboratory conditions on a specific standard setup as well as in real conditions in a survey of the existing base station with microwave relays. Presented measurement methodology of multi-frequency EMF from BS with microwave relays, validated both in laboratory and real conditions. It has been proven that the described measurement methodology is the optimal approach to the evaluation of EMF exposure in BS surrounding. Alternative approaches with much greater uncertainty (precaution method) or more complex measuring procedure (sources exclusion method) are also presented).

Sensor Interaction as a Source of the Electromagnetic Field Measurement Error

Abstract The article deals with analytical calculation and numerical simulation of interactive influence of electromagnetic sensors. Sensors are components of field probe, whereby their interactive influence causes the measuring error. Electromagnetic field probe contains three mutually perpendicular spaced sensors in order to measure the vector of electrical field. Error of sensors is enumerated with dependence on interactive position of sensors. Based on that, proposed were recommendations for electromagnetic field probe construction to minimize the sensor interaction and measuring error.

Quantum probes of timelike naked singularities in the weak field regime of f (R) global monopole spacetime

The formation of a naked singularity in $f(R)$ global monopole spacetime is considered in view of quantum mechanics. Quantum test fields obeying the Klein$-$Gordon, Dirac and Maxwell equations are used to probe the classical timelike naked singularity developed at $r=0$. We prove that the spatial derivative operator of the fields fails to be essentially self-adjoint. As a result, the classical timelike naked singularity formed in $f(R)$ global monopole spacetime remains quantum mechanically singular when it is probed with quantum fields having different spin structures. Pitelli and Letelier (Phys. Rev. D 80, 104035, 2009) had shown that for quantum scalar ($spin$ $0$% ) probes the general relativistic global monopole singularity remains intact. For specific modes electromagnetic ($spin$ $1$) and Dirac field ($% spin$ $1/2$) probes, however, we show that the global monopole spacetime behaves quantum mechanically regular. The admissibility of this singularity is also incorporated within the Gubser's singularity conjecture.

The Effect of Diode Response of Electromagnetic Field Probes for the Measurements of Complex Signals

Diode detectors present inside electromagnetic field probes are typically calibrated for linearity using continuous sinusoidal waveforms (CW). In this paper, it is shown that CW linearization is not adequate for the measurement of complex wireless communication signals with high peak-to-average power ratios. While previous analog and digital communication signals (1G and 2G) can be more easily corrected for linearity, newer 3G and 4G communication protocols employ complex modulations with stochastic signal envelopes. As a result, proper linearization depends on the diode response and signal characteristics, and large errors results if CW linearization is used. The errors introduced when measuring such signals with probes employing CW linearization are quantified in this paper. A numerical model of the diode response is provided and validated against measurements. Errors due to CW linearization can exceed 2 dB, whereas linearity errors within 0.4 dB are attainable using the proposed calibration procedures for even increased dynamic ranges.

A New Electromagnetic Field Probe by Using Printed Dipole Antenna

This paper presents a novel Electromagnetic field (E-Field) probe structure employing a printed dipole antenna to get isotropic pattern. The printed dipole is constituted by a variety of orthogonal dipole antenna array, and it is used in the design to reduce the complexity and cost. In this paper, we stimulate the printed dipole antenna and detector diodes by software, and the results confirm the validity of the printed dipole antenna. Moreover, the directivity of antenna array depends on the location of dipole antenna. By changing some design of the antenna, the probe achieves flat frequency response in 0.1GHz-10GHz.

Design of experiments and data-fitting techniques applied to calibration of high-frequency electromagnetic field probes

Characterization of electromagnetic field sensors requires that the behaviour of each sensor is investigated over the whole functional space, i.e., the range in which the device is expected to work. In most cases, for the sake of time reduction, experiments are run only over a subset of the functional space. The reduced extension of the experimental space limits the knowledge of the actual behaviour of the probe represented by the calibration factor K. Linear regression is a common technique to represent measurement data, but it is generally not applied to sensor calibration. Furthermore, no comparative study of experimental plans differing in the number and location of experimental points has ever been carried out nor has a methodology to determine the optimal degree of the regression polynomial been outlined. This paper compares the error variance between experimental points and fitted curve obtained using different experimental plans and regression polynomials.

Electromagnetic near field measurements by using magnet garnet crystal

An optical scanning electromagnetic field probe system consisting of an optic crystal substrate and a galvano scanner has been developed for high speed, low-invasive measurement of electromagnetic near field distribution. We measured magnetic field distributions above a microstrip line using several magnetic garnet crystal substrates and the probe system. We observed that the frequency response in the gigahertz range improved when we applied a magnetic bias to the crystal. In addition, a magnetic field component in a particular direction could be detected by controlling the direction of the magnetic bias.

Electromagnetic Source Azimuth Measurement Using Electrooptical Electromagnetic Field Probe

A new type electrooptical electromagnetic field probe was fabricated by combining three magnetic field sensors, each of which consists of a Mach-Zehnder modulator and an integrated annular antenna. The frequency response was flat from 50 MHz to 2.2 GHz. The average minimum detectable electromagnetic field intensity of the sensor is 2.22 mV/m. When the probe axis was pointed toward the electromagnetic radiation source, the highest sensitivity was obtained. The variation of the sensitivity is within plusmn0.5 dB with rotating the probe around its axis. This result indicates that the azimuth of the electromagnetic radiation source can be measured.

High Speed System for Measuring Electromagnetic Field Distribution

An optically scanning electromagnetic field probe system consisting of an electro-optic or magneto-optic crystal and a galvano scanner is proposed for high-speed electromagnetic field distribution measurements. We used this technique to measure electromagnetic field distributions near printed circuit boards or ICs to address electromagnetic compatibility problems or in designing electronic devices. With our scanning system, we can measure the electric field intensities of about 40,000 points with an area of 40 x 40 mm in about 3 minutes (4 ms per point) up to 2.7 GHz. We measured the electric near-field distribution above a five-split transmission line using a cadmium telluride (CdTe) electro-optic crystal. The measurement results showed that the spatial resolution of the system was less than 400 μm in the case of a common current with a crystal thickness of 1 mm. The electric near-field distribution above a microstrip line filter was measured using LiNbΟ 3 electro-optic crystal. Changes in the distribution according to the frequency were observed. The experimental results obtained using this system were compared with simulation results obtained using a finite-difference time-domain method. The overall results indicated that the measurement system is capable of accurately measuring electric near-fields. We also discuss the invasiveness of the measurement system, due to the electro-optic crystals, in terms of both the experimental and simulated results.

Invasiveness of an Optical Magnetic Field Probe

Electromagnetic field probes inevitably disturb the original distribution of the field when they are positioned close to a device. This disturbance in turn affects measurement accuracy and device operation. We developed an optical magnetic field probe, comprising a loop antenna element and an electro-optic crystal, for highly accurate magnetic near-field measurement in the GHz frequency range. We analyzed the invasiveness of the optical magnetic field probe quantitatively both experimentally and using finite difference time domain simulation. We found that eliminating the metal cable reduced the disturbance of the surrounding field that was to be measured. In addition, we investigated the magnetic field detection characteristics of the probe and its influence on the operation of a microstrip line. The optical magnetic field probe was less invasive and provided more accurate measurement.

Straight CTL cell with 3×3 cm test zone for calibrating EM field probes in air

Results are presented of a designed straight coupled transmission line (CTL) cell with a 3×3 cm test zone for calibrating small electromagnetic (EM) field probes up to about 900 MHz in air. The field uniformity and frequency bandwidth of the straight CTL cell are compared to those of a symmetric transverse electromagnetic (TEM) cell with the same afore mentioned test zone. It can provide the standard EM fields with high field uniformity and broadband frequency range simultaneously.

EMF probes calibration in a waveguide

This paper is devoted to an estimation of electromagnetic field probe calibration error, while the calibration is performed within a waveguide, due to the presence of conducting walls of the waveguide and their influence on the calibrated probe's transmittance. The presented estimations and measurements are performed for symmetric dipole antennas of different slenderness ratios. However, the approach is applicable to any type of electromagnetic field (EMF) standard and design of field probes.

Isotropic receive pattern of an optical electromagnetic field probe based upon Mach-Zehnder interferometer

This article describes a new idea for the design of electric field sensors that is informative for engineers studying sensors. However, there has been no experiment to show that such a sensor can be made. The phase difference between the light waves at the output ports of the sensors should be considered to realize the sensor. This article is devoted to an optical electromagnetic field probe based on a Mach-Zehnder interferometer. Unlike the electric sensors based on diode dipole technology, obtaining an isotropic receive pattern, in the case of an optical electromagnetic field probe, requires the use of three appropriately biased sensors connected in parallel before scalar summation. The configuration of such a sensor is discussed.