6,168 research outputs found
Measurement of Radiated Cyclostationary EMI
No full textWe have extended the method for modeling the stocha
stic EM near-field which has already been
described for stationary stochastic fields to the case
of cyclostationary fields. Areas of application are the
modeling of the electromagnetic interference radiated by
digital circuitry inside the system and also into
the environment, where the period of the cyclostationar
y EMI is given by the clock frequency of the digital
circuits. Stochastic electromagnetic fields with Ga
ussian amplitude probability distribution can be fully
described by auto- and cross correlation spectra of
the field components. The
cross correlation spectra
have to be known for the pairs of field components ta
ken at different spatial points (Russer et al., 2015a,
b).
We present methods for measurement and evaluati
on of stationary and cyclostationary stochastic
electromagnetic fields. The radiated electromagnetic inte
rference (EMI) of electroni
c circuitry is recorded
by two-point measurements of the t
angential electric or magnetic fi
eld components and by evaluating the
field autocorrelation functions and for each pair of field sampling points also the cross correlation
functions (Russer and Russer, 2015). In case of di
gital circuitry clocked by a single clock pulse, the
generated EMI is a cyclostationary process where the ex
pectation values of the EMI are periodically time
dependent according to the clock frequency and which have to be considered in modeling the EMI.
In this contribution we present the experimental char
acterization of cyclostationary radiated EMI by two-
point correlation measurements. The radiated EMI is
measured simultaneously by two field probes. The
measured signals are recorded by a digital sampling
oscilloscope and the cycl
ostationary auto- and cross
correlation spectra are computed from the measured da
ta. From this the propagation of the radiated EMI
is computed using the CTLM method (Russer et al., 2016).
References
Russer, J. A. and Russer, P.: Modeling of Noisy EM Fi
eld Propagation Using Correlation Information, in
IEEE Transactions on Microwave
Theory and Techniques, 2015.
Russer, J. A., Russer, P., Konovalyuky, M., Gorbuno
va, A., Baev, A., and Kuznetsov, Y.: Analysis of
Cyclostationary Stochastic Electromagnetic Fields, in
: International Conference on Electromagnetics in
Advanced Applications (ICEAA), 2015
Russer, J. A., Russer, P., Konovalyuky, M., Gorbuno
va, A., Baev, A., and Kuznetsov, Y.: Near-Field
Propagation of Cyclostationary Stochastic Electrom
agnetic Fields, in: International Conference on
Electromagnetics in Advanced A
pplications (ICEAA), 2015, 2015.
Russer, J. A., Cangellaris, A., and Russer, P.: Corre
lation Transmission Line Matrix (CTLM) Modeling of
Stochastic Electromagnetic Fields, 10 in: Proceeding
of: IEEE International Microwave Symposium, IMS,
San Farncisco, CA, USA, 2016
Correlation Transverse Wave Formulation (CTWF) for Modeling of Stochastic Electromagnetic Fields
No full textIn this work we apply the Correlation Transver
se Wave Formulation (CTWF) method for direct
computation of the auto- and cros
s correlation functions (ACFs and
CCFs) of stationary stochastic
electromagnetic fields. These ACFs and CCFs are com
puted from the Johns matrices, i.e. the discrete-
time TWF Green's functions and are directly related to the EMI power spectra.
Radiated EMI is represented by stoc
hastic EM fields. For efficient EMI compliant design and optimization
of circuits and systems the si
mulation methodologies based on the field autocorrelation and cross
correlation spectral densities are required. Semi-ana
lytic numerical methods based on Green's function
formalism already were presented in
(Russer and Russer, 2011a, 2015).
The Transmission Line Matrix (TLM) method is an e
fficient time-and space discrete numerical method for
modeling of complex electromagnetic structures (R
usser and Russer, 2011b, 2014). Introducing network
models allows the application of correlation matrix met
hods for the modeling of stochastic fields. This can
be done either by method of moments as discussed in
(Russer and Russer, 2015) or by applying network
oriented space discretising methods for EM field computation as for example the TLM method (Russer et
al., 2016).
Mode matching is the superposition of modal field solu
tions. If an electromagnetic structure is subdivided
into substructures and complete sets of modal field
solutions are known for the sub-domains, these modal
solutions form a complete basis and allow to expand the field solutions into these basis functions.
Choosing modal functions as the basis functions ensure
s that these functions are
already solutions within
the respective regions and we need
only to care that the boundar
y conditions are fulfilled. The mode
matching method is potentially exact if we allow infi
nite series expansions. Considering the modal basis
functions as the basis of a function space, Hilbert
space methods, in particular the method of moments
(Harrington, 1968), can be applied. Baudrand and Baj
on introduced Hilbert space methods to transform
integral formulations of electromagnetic field pr
oblems into algebraic ones (Baudrand, 2001). An
extension of this method has been given in the transve
rse wave formulation (Wane et al., 2003). Now, we
extend the Transverse Wave Formulation method to
compute auto- and cross correlation functions of
stationary stochastic
electromagnetic fields.
References
Baudrand, H.: Introduction au Calcul des Elements de
Circuits Passifs en Hyperfreequences, Cépaduès-
Éditions, Toulouse, 2001.
Harrington, R. F.: Field Computation by Mom
ent Methods„ IEEE Press,
San Francisco, 1968.
Russer, J. A. and Russer, P.: Stochastic electrom
agnetic fields, in: German Microwave Conference
(GeMIC), pp. 1-4, 2011a.
Russer, J. A. and Russer, P.: Modeling of Noisy EM
Field Propagation Using Correlation Information, in
IEEE Transactions on Microwave
Theory and Techniques, 2015.
Russer, J. A., Cangellaris, A., and Ru
sser, P.: Correlation Transmission Line Matrix (CTLM) Modeling of
Stochastic Electromagnetic Fields, in: Proceeding o
f: IEEE International Microwave Symposium, IMS,
San Francisco, CA, USA, 2016.
Russer, P. and Russer, J.: Transmission Line Matrix (TLM) and network methods applied to
electromagnetic field computation, in: Micr
owave Symposium Digest (MTT), 2011 IEEE MTT-S
International, pp. 1-4, IEEE,
doi:10.1109/MWSYM.201
1.5972622, 2011b
Rigorous design of magnetic-resonant wireless power transfer links realized with two coils
No full textMagnetic resonant wireless power transfer has been typically realized by using systems of coupled resonators. We show that the essential elements are only the coupled inductances. In fact, by starting from coupled inductances, and by introducing their conjugate image impedances, we can derive the series and parallel matching topologies that realize maximum wireless power transfer. By sacrificing some efficiency we show that we can realize a matched (lossless case) mid-range wireless power transfer link by using just one inductive coil on the secondary side and having the required capacitances all on the primary side (or viceversa). The proposed topology greatly simplifies the design; in addition, when tuning is required due to coils misalignment or to link distance variation, it can be attained without the need for a feed-back through the communication link. A preliminary experimental verification of the proposed approach is also presented
Cyclostationary characterization of electromagnetic interference with spread spectrum clocking
No full textSpread spectrum clocking (SSC) is used for data transmission in modern synchronous digital systems in
order to comply with electromagnetic compatibility (E
MC) regulations. In a synchronous digital system, a
single clock signal is delivered to all subsystems, where actions within each subsystem only occur during
the clock periods (Kao and Hsieh, 2009; Kawamoto
et al., 2014). Due to the periodic nature of a clock
signal, its bandwidth is very narrow. In an ideal rect
angular clock signal, in fact all the signal energy is
concentrated at a single frequency and the higher
order harmonics. Radiated electromagnetic
interference (EMI) originating from clock signals ther
efore also radiates all it
s energy at a very narrow
frequency band. The peak radiation power in such a
scenario can easily reach the limits defined by EMC
regulations.
When measuring the near-field emissions from th
e PCB under test, the existence of the spreading
spectrum effects need to be taken into account for
correct signal processing of the measured time domain
data. It is known that data containing emissions reveal
the cyclostationary properti
es of their second-order
stochastic characteristics. But in the case of SSC
the cyclic frequencies of
the correlation functions
become dependent on time lag, which in the case of
time-continuous functions could be described by a
Generalized Almost Cyclostationary model (Russer et
al., 2015a, b). But after the uniform discretization
the stochastic process could loose
the properties of the continuous one. The possible way for overcome
this problem is the de-spreading of the clock signa
l at the preprocessing stage of the algorithm for
revealing cyclostationary properti
es of the measured EMI data.
The comparison of the modeling and measurement
results shows the good agreement between the
characteristics of the composed model for the SSC
signal and corresponding c
haracteristics evaluated
from the near-field measurements of the EMI from t
he Spartan 6 FPGA electroni
c device. The proposed
model can be used for the prediction of spectral
characteristic of any m
easured and approximated
frequency modulation function using for the implementation
of the SSC. It can be also effectively used for
the necessary de-spreading procedure of t
he measured near-field time domain EMI data.
Kao, Y. H. and Hsieh, Y. B.: A Low-Power and Hi
gh-Precision Spread Spectrum Clock Generator for
Serial Advanced Technology Attachment Applicatio
ns Using Two-Point Modula
tion, IEEE Transactions on
Electromagnetic Compatibility, 51, 245-
254, doi:10.1109/TEMC.2008.2012115, 2009.
Kawamoto, T., Suzuki, M., and Noto, T.: 1.9-ps Jitte
r, 10.0-dBm-EMI Reduction Spread-Spectrum Clock
Generator With Autoca
libration VCO Technique for Serial-ATA
Application, IEEE Tr
ansactions on Very
Large Scale Integration (VLSI) Systems, 22,
1118-1126, doi:10.1109/TVLSI.2013.2257901, 2014.
Russer, J. A., Russer, P., Konovalyuk, M., Gorbuno
va, A., Baev, A., and Kuznetsov, Y.: Analysis of
Cyclostationary Stochastic Electromagnetic Fields,
in: International Conference on Electromagnetics in
Advanced Applications (ICEAA)
, 2015, pp. 1452-1455, IEEE, 2015a.
Russer, J. A., Russer, P., Konovalyuky, M., Gorbuno
va, A., Baev, A., and Kuznetsov, Y.: Near-Field
Propagation of Cyclostationary Stochastic Electrom
agnetic Fields, in: International Conference on
Electromagnetics in Advanced Applic
ations (ICEAA), 2015, pp. 1456-1459,
IEEE, 2015b
J.A. Daigneau
No full textPhotograph - J.A. Daigneau building, Athabasca, Alberta. It was built in 1912 by Joseph Daigneau and burnt down in 198
Author inscription in The Chinese slave-girl: a story of woman's life in China
No full textThis edition includes a gift inscription by author Rev. J.A. Davis, "To Rev. A. G. Russell with the warmest regards of the author J.A. Davis."Davis, John Agnell, 1839-1897
Group living homes for older people with dementia: Concept and effects
Get PDFEefsting, J.A. [Promotor]Pot, A.M. [Promotor]Depla, M.F.I.A. [Copromotor]Lange, J. de [Copromotor
A System for Dynamic Inductive Power Supply of Electric Vehicles on the Road
No full textA moving field inductive power transfer (MFIPT) system for supplying power to electric vehicles while driving along the route is described. This MFIPT system uses primary coils arranged below the pavement. The primary coils transmit the energy via an alternating magnetic field to a secondary coil located at the vehicle below its floor. Only those primary coils located below the secondary coil of a vehicle are excited. By this way losses and radiation in the environment are minimized.
The operation principle of the moving field inductive power transfer system is based on a switched DC-to-DC converter which converts the DC power supplied by the stationary power line to DC power delivered to the moving electric vehicle. The dynamics, the operating regimes and the power balance of the moving field inductive power transfer system and the costs for the implementation of the system are discussed.
The contactless power supply of electric vehicles on highways makes it possible to get along with battery capacities otherwise suitable only for shorter range. The batteries are used only in local traffic and on side roads where no moving field inductive power transfer system is installed. In areas where there are no inductive supply roads available, the inductive energy transmission system may still be used in stationary charging stations. Since only the primary coils below the vehicles are activated, high efficiency is achieved and the magnetic field is shielded against the environment.
The MFIPT system is especially interesting for intelligent autonomous electric vehicles. In transportation systems based on this combination the electric vehicles will exchange information with traffic management systems and with each other and thereby achieve a steady, energy-efficient traffic flow even at very high vehicle densities
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