Coding in optical CDMA networks with M-ary modulation: impact of selected physical imperfections

Author

Garba, Aminata A. ; Bajcsy, Jan

Author_Institution

Dept. of Electr. & Comput. Eng., McGill Univ., Montreal, Que.

fYear

2005

fDate

1-4 May 2005

Firstpage

1136

Lastpage

1140

Abstract

We consider optical CDMA network transmission, when M-level spreading sequences, channel coding and single-user decoding are utilized. We first explore the impact of noise from laser transmitters and photo-detectors on the spectral efficiency limits based on channel capacity calculations and consider the impact of practical laser pulse widths and wavelength separations on achievable data rates in practical OCDMA networks. Consequently, we consider the OCDMA spectral efficiency limits for power-limited fiber-optic transmission with and without the use of optical amplifiers. Finally, we present simulated BER performance results for selected coded OCDMA systems which utilize M-ary optical spreading sequences, turbo codes and Reed-Solomon codes, and can practically support hundreds of active OCDMA users at target BER of 10 ^-9

Keywords

Reed-Solomon codes; channel capacity; channel coding; code division multiple access; error statistics; modulation; optical fibre networks; optical transmitters; photodetectors; turbo codes; BER; M-ary modulation; M-ary optical spreading sequences; M-level spreading sequences; Reed-Solomon codes; channel capacity; channel coding; laser pulse widths; laser transmitters; optical CDMA networks; photo-detectors; power-limited fiber-optic transmission; single-user decoding; spectral efficiency; turbo codes; wavelength separations; Fiber lasers; Laser noise; Laser theory; Modulation coding; Multiaccess communication; Optical fiber networks; Optical modulation; Optical noise; Optical transmitters; Pulse amplifiers;

fLanguage

English

Publisher

ieee

Conference_Titel

Electrical and Computer Engineering, 2005. Canadian Conference on

Conference_Location

Saskatoon, Sask.

ISSN

0840-7789

Print_ISBN

0-7803-8885-2

Type

conf

DOI

10.1109/CCECE.2005.1557177

Filename

1557177