Direct-sequence code division multiple access: From radio communications to optical networks
نویسندگان
چکیده
A direct sequence optical code division multiple access technique is investigated. This paper introduces, first, the principles definitions of Code Division Multiple Access in radio communications. After that, the performances of Optical Code Division Multiple Access are evaluated in association with a realistic amplified optical channel model. To determine the performances obtained by this combination, different detection methods are investigated in an Optical cdma system. Threshold and multiuser detections are developed in association with Optical Orthogonal Codes: ooc and Prime Sequences: PS, specially designed to be adapted to fiber optic channel. Résumé Dans cet article, une étude des techniques d'accès multiple par répartition de code (CDMA) à séquences directes est réalisée. En premier lieu, les principales définitions du CDMA utilisé dans les systèmes de radio communications sont données. Par la suite, les performances du CDMA optique sont évaluées en y associant un model réaliste de canal optique amplifié. Afin de déterminer les performances obtenues par ce modèle, différentes méthodes de détection ont été mises en oeuvre dans le système CDMA optique, citons comme exemple le détecteur à seuil et le détecteur multi-utilisateur. De plus des codes spécifiques au CDMA optique sont évalués et associés à notre modèle de canal, parmi lesquelles les code optiques orthogonaux (OOC) et les séquences premières (PS).
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ورودعنوان ژورنال:
- Annales des Télécommunications
دوره 58 شماره
صفحات -
تاریخ انتشار 2003