We 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.
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