
108 Optical Fiber Communication Systems with MATLAB
®
and Simulink
®
Models
At
the output of MZIM, the optical elds from the two arms are coupled and interfere with
each other either constructively or destructively. This enables the “ON–OFF” modulation
of the light wave intensity. Figure 4.6 shows a sample of a packaged MZIM and its modula-
tion
transfer characteristic [17] whose 3 dB bandwidth reaches 26 GHz.
MZIM
can be classied into single-drive and dual-drive types, which are described in
the next subsections.
4.2.3.1 Single-Drive MZIM
A
single-drive MZIM has only one single driving voltage applied to either arm of MZIM.
For instance, it i