Title :
Optical OOK-CDMA and PPM-CDMA systems with turbo product codes
Author :
Argon, Cenk ; McLaughlin, Steven W.
Author_Institution :
Sch. of Electr. & Comput. Eng., Georgia Inst. of Technol., Atlanta, GA, USA
fDate :
9/1/2002 12:00:00 AM
Abstract :
The application of turbo product codes (TPC) in intensity-modulated direct-detection optical code-division multiple-access (CDMA) systems with ON-OFF keying or binary pulse-position modulation is proposed in this study. Optical multiple-access interference caused by other users is the main source of noise that degrades system performance and limits the total number of active users in an optical CDMA system. In this work, the original turbo product decoding algorithm is modified according to the binary memoryless channel model. It is shown that the implementation of TPCs in an optical CDMA system provides significant improvement of the bit-error rate, hence, permitting a higher number of active users with optical orthogonal codes (OOC) of less weight. The proposed TPC has about 20% overhead, but the reduction in the weight of the OOC reduces the system bandwidth to less than half to that of the comparable uncoded system.
Keywords :
amplitude shift keying; code division multiple access; optical fibre networks; optical modulation; pulse position modulation; telecommunication channels; turbo codes; ON-OFF keying; PPM-CDMA systems; active users; binary pulse-position modulation; bit-error rate; decoding algorithm; intensity-modulated direct-detection optical code-division multiple access systems; memoryless channel model; optical CDMA system; optical OOK-CDMA; optical multiple-access interference; optical orthogonal codes; system bandwidth; system performance; turbo product codes; Active noise reduction; Intensity modulation; Modulation coding; Multiaccess communication; Multiple access interference; Optical modulation; Optical noise; Optical pulses; Product codes; Pulse modulation;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2002.802224