Design of new family of two-dimensional wavelength-time spreading codes for optical code division multiple access networks

A new two-dimensional code family is proposed for OCDMA networks:having ort hogonal properties in both the 'wavelength' and 'time' domains. This code f amily can be easily constructed from the Hamming correlation concept and di mension expansion, and can also be physically implemented by using an array of Bragg gratings. Numerical simulations and a theoretical analysis demons trate an improved bit error rate performance with much smaller number of wa velength sets when compared to previous approaches.