Analyses of constraints on high speed optical code division multiplexing access (OCDMA) link parameters due to fiber optic chromatic dispersion Y. Zouine c , I. Dayoub a , S. Haxha b, * , J.M. Rouvaen a a IEMN DOAE (UMR CNRS 8520) UVHC, Le Mont-Houy, 59313 Valenciennes Cedex 9, France b Photonics Group, Department of Electronics, University of Kent, Canterbury CT2 7NT, UK c LEIMP Laboratoire d’e ´lectroniques, d’instrumentations et mesures physiques, Faculty of Science and Technology, BP 509 Boutalamine, Errachidia, Morocco Received 14 June 2007; received in revised form 4 October 2007; accepted 5 October 2007 Abstract In direct sequence-optical code division multiplexing access (DS-OCDMA) system networks, data rate and data spreading technique involved in such systems require a high chip rate. Transmission link in these systems is significantly affected by the fiber chromatic dis- persion. In this study, we have developed and employed a simple model to estimate the G652 fiber dispersion effects. OCDMA technique has been employed to investigate fiber chromatic dispersion effects on multiple access interference (MAI). We have found that, at a short optical fiber length, the optical fiber dispersion has a significant impact on the high data rate transmission systems (higher than 750 Mbit/ s). The performance and optimization of optical orthogonal code (OOC) in the OCDMA system is reported. We have demonstrated that, for a high data rate, even if dispersion compensated devices are not deployed, the BER can be significantly improved when the OOC desired length is selected. We have shown that when compensation dispersion devices are not deployed in the system, there is a trade off between the limited dispersion effects and the MAI. Ó 2007 Elsevier B.V. All rights reserved. 1. Introduction The success and extensive application of code division multiple access (CDMA) in the wireless area has renewed attention in exploring its application in the optics communi- cation systems. Optical CDMA (OCDMA) has for a long time been the subject of research because of its inherent abil- ity to support asynchronous burst communications. Initially it was employed for local area [1], then for access network applications [2,3] and more recently for emerging networks such as generalized multiprotocol label switching [4–6]. Optical communication networks are widely reported in the literature, particularly, in the access of optical transmis- sion systems such as fiber-to-the-home (FTTH) or fiber-to- the-curb (FTTC). OCDMA is broadly studied as a possible solution to provide high quality transmission [7–11]. It is already known that several network topologies can be employed for FTTH such as single star, active double star and passive star (PDS). The PDS also know as a passive optical network (PON) is used as a result of flexible config- uration and low cost [12,13]. Depending on the signal mul- tiplexing techniques, various PONs can be employed. In time division multiple access (TDMA) which uses a time- division-multiplexing (TDM) technique, N time slots are assigned to N corresponding users. However, there are seri- ous limitations of this technique. The increase of the band- width is restricted by the bandwidth limitations of the electronic devices, and only synchronous network configu- rations can be used. The next technique is wavelength divi- sion multiple access (WDMA), where a wavelength is assigned to each user. In this case the bandwidth is used efficiently and the asynchronous transmission can be 0030-4018/$ - see front matter Ó 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.optcom.2007.10.079 * Corresponding author. Tel.: +44 (0) 1227 827257; fax: +44 (0) 1227 456084. E-mail address: S.Haxha@kent.ac.uk (S. Haxha). www.elsevier.com/locate/optcom Available online at www.sciencedirect.com Optics Communications 281 (2008) 1030–1036