  We designed a Reconfigurable Optical Add/Drop Multiplexer (ROADM) based on a
subcarrier add/drop node in an optical communication system that is suitable
for all kinds of optical multiplexing signals. To achieve this goal, at first,
we designed an optical comb generator based on a dual-drive Mach Zehnder. The
new ROADM setup is validated by a 100 Gb/s 4-subcarrier. In the final step, we
checked the performance of the system in terms of the bit error rate (BER)
versus optical signal-to-noise ratio (OSNR) to verify the add/drop operation
had been successfully performed at 10-9 and is suitable to apply in an
all-optical multiplexing technique.
