Performance evaluation of 2D wavelength/time optical CDMA system with optical hard-limiters by numerical modeling

We present the modification of a decoder for 2D wavelength/time (W/T) optical code division multiple access (O-CDMA) system by optical hard-limiters. The performance improvement of the system using the proposed decoder modification is shown by numerical simulation of the bit error probability as a function of active user number and weight of codeword for different decoder topologies. The influence of the non-ideal properties of the optical hard-limiters used on the bit error probability in the system is studied. The performance evaluation shows that the dependence of bit error probability versus the codeword weight has a local minimum, which allows an optimum codeword weight to be chosen for achieving the minimum bit error probability in a 2D W/T O-CDMA system for given system parameters.