Optimum Threshold Detection over Folded Optical Coding Network - Pilot Wavelength on Optical CDMA Threshold Detection

Over two-dimensional Folded Optical Orthogonal
Coding (FOOC) network, a simple threshold detection
scheme is illustrated to detect the number of
simultaneous network users and to adjust the
detection threshold value instantaneously. A special
wavelength called pilot wavelength is added into the
original transmission patterns of every network
user. At the receiver, we can acquire the number of
simultaneous network users from the power of the
pilot wavelength. Consequently, by adjusting the
detection power threshold to the optimum threshold
value, we can decrease the bit error rate (BER) and
improve the system performance for the discussed two-
dimensional optical code-division multiple-access
(2D-OCDMA) network. Compared with conventional
network system adopting prime codes or modified
prime codes, the proposed FOOC network with pilot
wavelength threshold detection shows an enhanced BER
performance and supports more simultaneous network
users.