
18 Optical Fiber Communication Systems with MATLAB
®
and Simulink
®
Models
of the light waves in the transverse plane is similar to the elastic waves propagating
in a string or wind instrument, terminated with the two ends open or closed. To nd
the number of optically guided modes one has to nd the conditions under which the
light waves would be conned or resonating. Normally, this condition is the eigen-
value equation that is derived from the wave equation and that satises the boundary
conditions.
Associated
with
each
solution
of
the
optical
wave
equation
is
the
propagation
wave
number
of
each
guided
wave,
which
is
derived
from
the
eigen ...