DocumentCode :
1304397
Title :
Efficient Use of PPM in Spectral-Amplitude-Coding Optical CDMA Systems
Author :
Shalaby, Hossam M H
Author_Institution :
Dept. of Electron. & Commun. Eng., Egypt-Japan Univ. of Sci. & Technol. (E-JUST), Alexandria, Egypt
Volume :
30
Issue :
22
fYear :
2012
Firstpage :
3512
Lastpage :
3519
Abstract :
A prominent technique, for reducing the effect of phase-induced intensity noise (PIIN) in spectral-amplitude-coding optical code-division multiple-access (SAC-OCDMA) systems, is proposed. In this technique, each user is assigned two orthogonal code sequences, selected from a minimum cross-correlation code set. In addition, two-level M -ary pulse-position modulation (MPPM) scheme is adopted, where each level corresponds to a code sequence. This technique decreases the effect of PIIN and allows transmission at high data rates. The bit error rate (BER) of the proposed system is derived, taking into account the effects of PIIN, shot noise, and thermal noise. Two performance measures of this system, namely the BER and maximum achievable number of users, are compared to that of traditional systems adopting complementary and non-complementary keying. Our results reveal that the proposed technique allows each user to transmit at high data rates, compared to traditional techniques, while keeping the BER well below a prescribed threshold. Finally, our results are extended to higher levels of MPPM schemes with multicode modulation.
Keywords :
amplitude modulation; code division multiple access; error statistics; optical correlation; optical modulation; optical noise; orthogonal codes; phase noise; pulse code modulation; shot noise; thermal noise; BER; MPPM scheme; PIIN; bit error rate; code sequence; complementary keying; high data rate transmission; minimum cross-correlation code set; multicode modulation; noncomplementary keying; optical SAC-OCDMA system; optical code-division multiple-access; orthogonal code sequences; performance measurement; phase-induced intensity noise; shot noise; spectral-amplitude-coding; thermal noise; two-level M-ary pulse-position modulation; Adaptive optics; Bandwidth; Bit error rate; Modulation; Noise; Passive optical networks; Receivers; $M$-ary pulse-position modulation ($M$ PPM); Bit-error-rate (BER); modified prime sequence (MPS) codes; modified quadratic congruence (MQC) codes; multicode modulation; optical code-division multiple access (OCDMA); spectral-amplitude coding (SAC);
fLanguage :
English
Journal_Title :
Lightwave Technology, Journal of
Publisher :
ieee
ISSN :
0733-8724
Type :
jour
DOI :
10.1109/JLT.2012.2222017
Filename :
6319339
Link To Document :
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