
34-16 Electromagnetic Variables
Strictly speaking, wave variables and S-parameters can only be applied to linear networks. is is
important because many publications are devoted to the so-called large-signal S-parameter measure-
ments
. e in
terpretation
of su
ch
re
sults
is no
t
sim
ple,
an
d
gr
eat
ca
re
mu
st
be em
ployed
in th
e
co
rrect
de
termination
of th
e
ch
aracteristic
im
pedance
of th
e
sy
stem
[2
6]
. In th
e
ca
se
of an
alysis
of la
rge-signal
or n
onlinear
c
ircuits,
t
wo
m
ethods
e
xist
to i
ntroduce
t
he
w
ave
v
ariables:
•
Vo
lterra
s
eries
r
epresentation
[
28]
•
Ha
rmonic-balance
m
ethod
[
26]
Both
me
thods
tr
ansform
th
e
no
nlinear
ci
rcuit
in
to
a nu
mber
of li
near