Error Probability Bound Considering Beat Noise in 2-D OCDMA Systems

Abstract

Considering a 2-Dimensional Optical Code Division Multiple Access (2-D OCDMA) system using spreading codes in both time and wavelength domains, we study in this paper theimpact on the performance of one of the most predominantperformance limitation which is beat noise due to the photodetection. The beat noise impact is correlated with the wellknown OCDMA limitation named Multiple Access Interference (MAI). Our contribution is to assess, through a theoretical analysis, an error probability bound of a system working in incoherent or partially coherent optical regime. Thanks to the theoretical error probability expression we have developed, the specifications and requirements needed to neglect beat noise effect in a 2-D OCDMA system with a conventional receiver are easily obtained. For a targeted Bit Error Rate (BER), and a given number of active users, one can determine from our results, the 2-D code family parameters, the available data rate and the optical source characteristics, required to be free of beatnoise impact.

Keywords

• beat noise
• code division multiple access
• multi wavelength optical orthogonal codes
• optical networks