radiated interference emission source

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Radiated emission measurement of a cell phone processor module using TEM cell

Radiated emission measurement of a cell phone processor module using TEM cell

Billions of cell phones have been purchased every year in the world. They are widely used in people’s daily life. Though there is no direct evidence, people doubts its influence on health [1-2]. They are also emission source that could influence the safety of airplane. Several airplane accidents are found caused by electromagnetic interference (EMI) [3]. One of the main EMI sources in airplane is the cell phone. That’s why the Federal Communications Commission (FCC) [4] and Federal Aviation Administration (FAA) [5] regulations prohibit the use of cell phones on airplane.
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EMC study of an automotive application

EMC study of an automotive application

In this report, models of switch, relay, cable, motor and SCU are firstly developed in PSPICE so that the potential noise sources can be pointed out. Some models are validated by experiments. Our experience and the analysis and experiments described in this report show that the EMI is unwanted oscillatory current or voltage noise sources originated by transient. The transient may be opening and closure of switch, bouncing of relay, switching of MOSFET or commutation of motor, etc., and potential noise sources produced by transient will conduct and radiate interference to surrounding. Radiation models are constructed to find correlation between noise source and radiated emission. One model used in predicting radiated emission in low frequency has been presented and the condition for use is described.
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Characterization of the measurement uncertainty for the electromagnetic conducted and radiated emission test

Characterization of the measurement uncertainty for the electromagnetic conducted and radiated emission test

The Electromagnetic Interference (EMI) in electrical and electronics within the stipulated radio spectrum often exists and not directly visible from the outside of the equipment. It deals with the generation, transmission and reception of the unintended radio signals. This interference phenomenon can be described in a coupling model which are the source, coupling path and victim. In order for the interference to take place from the source, the coupling path can be radiative or the radiated emission (RE), conductive, capacitive and inductive for conducted emission (CE) [1]. Since it occurs over a broad spectral range from very low frequencies up to millimeterwave range and above, the manufacturer is obliged to declare the conformity with the achieved goals of the required directive; a harmonized and compatible level regarding the emissions and immunity of the equipment [2]. The directive has been recognized in the US in 1979 by introducing the FCC article 15 subpart J on emission restrictions for computers [3].The EMC standards clearly specify the limits and what is to be measured – the “measurand” and to define the method for measuring it. Nowadays, advancement in technology, consumer demand and enforcement requirements on an accredited lab test has resulted in acquiring ISO 17025 (General requirements for the competence of testing and calibration laboratories) certification [4].
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Mobile Source Emission Inventory In MBMB Area

Mobile Source Emission Inventory In MBMB Area

1. The emission inventory for this thesis covers the road that in the first quarter of MBMB area which include roads at Sungai Udang, Tangga Batu, Tanjong Keling, Bukit Rambai, Klebang Besar, Bertam, Balai Panjang, Cheng, Tanjong Minyak and Paya Rumput.

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Ray Interference: a Source of Plateaus in Deep Reinforcement Learning

Ray Interference: a Source of Plateaus in Deep Reinforcement Learning

What makes it better? There are essentially three approaches: reduce interference, reduce coupling, or tackle ray interfere head-on. Assuming knowledge of the components of the objective, the multi-task litera- ture offers a plethora of approaches to avoid negative interference, from modular or multi-head architectures to gating or attention mechanisms [3, 7, 32, 37, 41, 44]. Additionally, there are methods that prevent the inter- ference directly at the gradient level [5, 47], normalize the scales of the losses [15], or explicitly preserve ca- pacity for late-learned subtasks [18]. It is plausible that following the natural gradient [1, 28] helps as well, see for example [4] (their figures 9b and 11b) for prelimi- nary evidence. When the components are not explicit, a viable approach is to use population-based methods that encourage diversity, and exploit the fact that dif- ferent members will learn about different implicit com- ponents; and that knowledge can be combined [e.g., using a distillation-based cross-over operator, 9]. A possibly simpler approach is to rely on innovations in deep learning itself: it is plausible that deep networks with ReLU non-linearities and appropriate initialization schemes [13] implicitly allow units to specialize. Note also that the interference can be positive, learning one component helps on others (e.g., via refined features). Coupling can be reduced by introducing elements of off-policy learning that dilutes the coupled data distri- bution with exploratory experience (or experience from other agents), rebalancing the data distribution with a suitable form of prioritized replay [35] or fitness shar- ing [33], or by reward shaping that makes the learning signal less sparse [2]. A generic type of decoupling solution (when components are explicit) is to train sep- arate networks per component, and distill them into a single one [21, 32]. Head-on approaches to alleviate ray interference could draw from the growing body of continual learning techniques [22, 29, 30, 36, 40].
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An Improved Model for Estimating Radiated Emissions from a PCB with Attached Cable

An Improved Model for Estimating Radiated Emissions from a PCB with Attached Cable

Cable attached on a PCB is a well-known source of unintentional radiated emissions due to its large dimension relative to the PCB [1]. The study on this kind of structure has gained a lot of interest as it is one of the most commonly seen setup of electronic equipment. There are a few recent papers on the study of EMC effect of attached cable and simplified models are proposed to estimate radiated emission from such structure [1–7]. These studies showed that the electromagnetic field coupling of noise sources from PCB traces to the attached cable can be modelled as an equivalent board-cable model driven by a common-mode source. Shim and Hubing showed that the magnitude of this common-mode noise source generated through voltage-driven mechanism was related to the capacitance of the PCB trace and signal return plane [2]. Based on this, Deng et al. proposed that if the magnitude of the common-mode voltage source of such model was known, a closed-from equation can be used to estimate the maximum radiated E field at resonant frequency of such model [3]. Similar approach was taken by Wang et al. to investigate the maximum radiated E field of PCB with attached cable whereby the PCB was shielded with a conducting enclosure [4]. The enclosure and attached cable were modelled as an asymmetrical dipole instead of a monopole as in Deng’s method. However, the noise coupling mechanism in an actual product is usually too complicated to be described by a simple equation due to multiple noise sources and coupling paths. Park et al. presented an alternative to circumvent this problem by combining the measured common-mode current on the attached cable and simulation of the Radiation Transfer Function to predict the radiated emission of a box-source-cable model [8].
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EMC Electromagnetic Compatibility (

EMC Electromagnetic Compatibility (

– Supress the emission at its source (“Nip it in the bud!”) – Make the coupling path as inefficient as possible.. – Make the receptor less susceptible to the emission.[r]

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Influence of Reactive Volatile Organic Compounds on Ozone Production in Houston Galveston Brazoria Area

Influence of Reactive Volatile Organic Compounds on Ozone Production in Houston Galveston Brazoria Area

TCEQ modifies Texas Ozone Season Day (OSD) data by State of Texas Air Reporting System (STARS) and produces AIRS Facility Subsystem (AFS) archived ASCII file format which is compatible for Emission Pro- cessing System (EPS3). “afs.osd_2006_with_ards_removed_CB06_RPOlcp_v3” under Rider 8 program was used for case HGB point source emissions. Emissions files for area source, on-road source, non-road source and biogenic source were collected from TCEQ Rider 8 program [16] which was generated by EPS3, MOVES, NON-ROAD and GloBEIS model respectively [18]. Meteorological data and boundary condition data files gen- erated by WRF and GOES-Chem models and these files were also collected from TCEQ [16]. For case ALL, HGB and WOP, same meteorological, boundary conditions, land use and other input files were used. Only emissions input files were developed for the different emissions scenarios by EPS3.
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EMI reduction on high speed PCB using electromagnetic bandgap structure

EMI reduction on high speed PCB using electromagnetic bandgap structure

In high-speed digital circuits, the flow of the time-varying currents through vias between in multi-layer PCB design, result in radiations as well as switching noise (SSN) which is often induced in such circuitries. This noise is created whilst many outputs of a digital circuit switch at the same time. In addition, SSN depends on the geometry of the PCB. Therefore, it cannot be quantified precisely. Current traces are another issue where various studies have been concentrated on modeling this phenomenon (Shahparnia & Ramahi, 2007). The rapid increase of frequency clock is another primary source of switching noise. Recently, the uses of electromagnetic bandgap (EBG) structures have been introduced as an inexpensive effective method for SSN suppression in the gigahertz frequency bands (Shahparnia et al., 2004). By introducing the EBG structure to PCB design, it is possible to suppress switching and other noise generated within boards for frequencies in the gigahertz frequency range. In the work of (Shahparnia et al., 2004), the EBG cells have been surrounding the port of exitation as shown in Figure 2.16 (a) . Later, the boad was going under test by using a monopole antenna that will detect the radiated signals from the board as illustrated in Figure 2.16 (b). The results shows segnificant reduction of the incoming noise as shown in Figure 2.16 (c).
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Suitable Impedance Boundary Condition Applied to the Enhancement of the Electric Field Radiated by a High Frequency Surface Wave Radar

Suitable Impedance Boundary Condition Applied to the Enhancement of the Electric Field Radiated by a High Frequency Surface Wave Radar

On the contrary, when the line source is located over a ground with a negative permittivity, as shown in Fig. 4(b), there are two modes of propagation depending on the distance to the source. Close to it, the total magnetic field is equal to the surface wave, and at a larger distance the total magnetic field is equal to the sky wave. Similar results have been observed on a metallic plane at optical frequencies for which the interface behaves like a metamaterial [19]. In this case, the first order and FEKO solutions are not identical. Indeed, the first order solution is not accurate when the soil has a permittivity close to the unity.
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The application of wire mesh ground plane in open area test site for radiated emission measurement

The application of wire mesh ground plane in open area test site for radiated emission measurement

In radiated emission testing, electronic or electrical devices are tested for their electromagnetic radiation in order to comply with regulations and standards. There are four widely accepted facilities for measuring emission levels of the antenna which are OATS, Semi-Anechoic Chamber (SAC), Mode Stirred Chamber (MSC), and Gigahertz Transverse Electromagnetic (GTEM) Cell. The Federal Communication Commission (FCC) and European Norms (EN) suggested that the test should be conducted by using OATS for measurements in order to achieve the expected measurement with reduced error rate [2].
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Inverse Source Problem from the Knowledge of Radiated Field Over Multiple Rectilinear Domains

Inverse Source Problem from the Knowledge of Radiated Field Over Multiple Rectilinear Domains

The analysis is performed by means of the Singular Values Decomposition (SVD) of the relevant linear integral operator (radiation operator). Here we focus the attention on the increase of the information content in dependence of the added knowledge of the radiated field over a second observation domain by pointing out the different behavior when the domains are in Fresnel or near zone [1, 2]. Therefore, the work is organized as follows. Section 2 gives the formulation of the inverse source problem and the results for a single observation domain are briefly recalled. Section 3 addresses the problem of the determination of the magnetic source starting from the knowledge of the field over two domains located in Fresnel zone and an estimation of the NDF behavior is provided by resorting to the results in [2]. Section 4 is concerned with the case of the observation domains in the near zone and reconstruction examples are presented with noise-free and noisy data. Finally, conclusions follow.
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PM 2.5 and Ozone Permitting and Modeling in the Age of MERPs. Kristin Fritchman. October 1, 2019

PM 2.5 and Ozone Permitting and Modeling in the Age of MERPs. Kristin Fritchman. October 1, 2019

PM 2.5 MERPs for Selected Source Standard Precursor Emission Rate (tpy) Src.. PM 2.5 MERPs for Selected Source Standard Precursor Emission Rate (tpy) Src.[r]

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Equivalent wire model and travelling wave mode method to analyse the radiated emission of a bent microstrip line

Equivalent wire model and travelling wave mode method to analyse the radiated emission of a bent microstrip line

2D Radiation pattern of a 90° bent microstrip line with unmatched termination operating in 2 different frequencies.. Results are calculated based on analytical forn1Ulation.[r]

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Anten theor basics

Anten theor basics

– is defined for large distances from the antenna, where the spatial (angular) distribution of the radiated power does not depend on the distance from the radiation source. – is indepe[r]

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A Universal Condition Satisfied by the Action of Electromagnetic Radiation Fields

A Universal Condition Satisfied by the Action of Electromagnetic Radiation Fields

The action (the product of radiated energy and the time of emission) of the radiation fields generated by four types of radiators, namely, short electric di- pole, small magnetic dipole, travelling wave antenna and bi-conical antenna is investigated with special reference to the charge associated with the cur- rent waveform which is responsible for the radiation. The results obtained can be summarized by the order of magnitude inequality A ≥ h 2π → ≥ q e where A is the action (product of the radiated energy and the time of emis- sion), h is the Planck constant, q is the charge associated with the current that gave rise to the radiation and e is the electronic charge. The condition
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Use of Acoustic Emission for Testing Resistance of Hooves

Use of Acoustic Emission for Testing Resistance of Hooves

The acoustic emission method is based on physical measurements of elastic and traction waves propagating through the object material or on its surface. These stress waves are generated with the occurrence of plastic deformations in the material that is exposed to external forces (mechanical stress) (Miller et al., 2005). For the estimating of the damping magnitude in practice, basic calibration source of AE emissions, referred to as the Pen Test (Scruby, 1987), is commonly used. This form of testing represents a sudden quantum mitigation of the force affecting the object’s surface in the perpendicular direction, resulting in a sharp pulse. The Pen Test is used to measure the damping and velocities of wave propagation in a given material, as well as to calibrate the AE sensors, or to express the intensity of AE sources related to the Pen Test (Yonn et al., 1995). The whole process of emission and detection of AE involves several procedures including the acoustic emission event, propagation of tensile waves from the source to the sensor, detection of tensile waves using the sensor and transformation to electrical signal, and final estimate of the resulting electrical signal of AE using a measuring device (Dickinson, 1990).
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Toward coexistence and sharing between IMT-­advanced and existing fixed systems

Toward coexistence and sharing between IMT-­advanced and existing fixed systems

With equipment that just conforms to the standards, it is unlikely to be possible to use a macrocellular IMT-Advanced BS in the same area as a macrocellular FWA BS if LOS path exists between the two antennas and each site is in the main beam of the other site’s antenna (i.e., a worst case scenario) without mitigation techniques. As shown in Table 9, by taking ACIR into account, if the BSs operate on the same radio channels they can not coexist for a distance of 8 km or less, because the additional isolation values are 55 dB as aforementioned from the figures. However, coexistence the two BSs in co-channel frequency can be achieved for different separation distances when spectral emission mask of FWA BS is applied as in Table 8. Using ACIR, it makes 1st and 2nd Adjacent channels offsets useless even up to 8 km separation, while 14 MHz adjacent channels may be used for the separation distances in Table 8.
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Design of a Multiband Patch Antenna for 5G Communication Systems

Design of a Multiband Patch Antenna for 5G Communication Systems

DOI: 10.4236/ojapr.2018.61001 2 Open Journal of Antennas and Propagation 2.45 GHz [3]. A circularly polarized switched beam antenna with pattern diver- sity for Wi-Fi applications covers an angular range of 180 degrees with 7 dB of ripple and with the maximum gain of 2.8 dB [4]. This proposed antenna also can be worked for Wi-Fi system which gives more bandwidth about 150 MHz, direc- tivity gain is about 6 dBi from the above literature papers. For improving Wi- MAX frequency and bandwidth in recent years, several printed monopole an- tennas [5] [6] and slot antennas [7] [8] have been proposed for Wi-Fi/WiMAX applications. However, most of them have large dimensions and do not pay at- tention to interference suppression [9]. In this paper, WiMAX and Wi-Fi both are proposed which works on small dimensions about 3.5 × 3.6 × 1 mm 3 and
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Diverse young stellar populations in the intermediate-redshift radio galaxies 3C 213.1 and 3C 459: implications for the evolution of the host galaxies

Diverse young stellar populations in the intermediate-redshift radio galaxies 3C 213.1 and 3C 459: implications for the evolution of the host galaxies

3C 459 is identified with a 17.55 V magnitude N-galaxy at a red- shift of 0.2199 (Spinrad et al. 1985; Eracleous & Halpern 1994) and is classified as a narrow-line radio galaxy (Tadhunter et al. 1993), albeit with relatively low emission line equivalent widths and evi- dence for strongly blueshifted components (Holt 2005). It was first noted as unusual during a spectroscopic study of a sample of galax- ies by Miller (1981) who found that, unusually for a radio galaxy, its spectrum shows higher order Balmer lines in absorption. On this basis, it was tentatively identified as an elliptical with recent star for- mation (see also Tadhunter et al. 2002). Another interesting feature of this source is that, based on IRAS observations, its far-IR lumi- nosity is unusually high for a radio galaxy (L IR = 1.6 × 10 12 L ⊙ ) – approximately 10 times brighter than most other radio sources from the 2 Jy sample at comparable redshifts (see Tadhunter et al. 2002, 2007). This leads to its classification as an ultraluminous infrared galaxy (ULIRG; see Sanders & Mirabel 1996 for definition). In common with many ULIRGs, the host galaxy of 3C 459 is not a normal, quiescent elliptical galaxy, but instead exhibits a fan-like protrusion suggestive of a recent tidal encounter (Heckman et al. 1986). In the radio, 3C 459 is also unusual in the sense that it shows a highly asymmetric double-lobed Fanaroff–Riley type II (FRII) ra- dio structure of diameter 8.5 arcsec (27 kpc), as well as a strong steep spectrum core (e.g. Thomasson, Saikia & Muxlow 2003).
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