Optical Spectral Amplitude Code Division Multiple Access System

A system is proposed and analyzed which fully utilizes the bandwidth available in the optical medium. This optical code-division multiple-access system illusl rated in Figure l has its signature sequences on-off encoded on the frequency bands of the optical beam. Two suboptimal detector options for multi-user operation are considered: an optimized single-user detector and a multistage detector. The analysis is performed using a large deviation theory approximation and further verified by simulation. The advantages of this system over the conventional time-ellcoded system include the larger number of low crosscorrelation sequences available and the implementation of efficient decoders for low error probability detection.