
457Digital Optical Modulation Transmission Systems
11.3.2.2 Phasor
R
epresentation
f
or
R
Z33
M
odulation
Key
parameters
and
initial
phasor
representation
for
generation
of
RZ33
pulses
are
shown
in
F
igure
1
1.6a
a
nd
b
.
T
he
r
ed
v
ector
i
s
t
he
s
um
o
f
t
wo
i
nitialized
eld
v
ectors.
The
values
of
the
key
parameters
are
V
bias
= V
π
for both arms; the RF driving signal on
each
arm
has
an
amplitude
of
V
π
/2 (i.e., V
p–p
= V
π
), swings in opposite directions, and oper-
ates
a
t
h
alf
o
f
t
he
b
it
r
ate
(R/
2);
a
nd
m
odulating
f
requency
f
m
= 20 GHz.
At
FWHM
positions
of
the
optical
intensity
pulse,
E
o
= ±
1 2
and
the
eld
component
vectors
E
1
and E
2
form with the horizontal ...