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About classical electrodynamics
The
109 Experiment
He agre
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Crosstalk (Noise) in Digital Systems
Pages
1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , some of which is in two
of my books. The argument starts at page 30 of one book , and at page 4 of the other book
, continuing on page
55 . Here in
figure 9.2 we see “a very narrow pulse introduced at the front end of the
active line. If there were no parallel passive line nearby, this pulse
would travel down the active line (at the speed of light for the
dielectric) more or less unchanged,” in a TEM mode. “However, as the other
two traces show, the presence of the passive line caused the original
narrow pulse to break up into two similar pulses.”
He agre
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Published
in 1967, this paper of mine announced that crosstalk between parallel
conductors involved two velocities. If a asignal is delivered to an
(active) conductor in a surface microstrip or buried stripline in the
presence of a parallel second (passive) conductor, the original signal
breaks up into two signals, the Odd Mode and the Even Mode. In the odd
mode, the signal in the two sires is equal and opposite. In the even mode,
the signal in the two conductors is equal, See the diagram. However, using
the method of images, it is preferable to think in terms of this diagram , where the
active line A on the top left has its image B below, and the passive line P
on the right has its image Q below. In each mode, it is as though pairs of
conductors are shorted together as shown.
In the
case of the surface microstrip, more of the Odd Mode signal is in the air,
so that the effective dielectric constant is lower. This leads to a higher
velocity. However, in the case of buried striplines between two voltage planes,
the dielectric is all epoxy glass, and so the velocity of the two modes,
odd and even, is the same. In the surface lines, the two modes separate
out, but in the buried lines, the two modes stay together. In the buried
lnes, the signals are pure TEM. In the case of the surfaace lines, the
signals approximate closely to TEM.
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