Capacity research of OCDMA system in intersatellite communication

OCDMA (optical code-division multiple access) technology applied in intersatellite optical communications is novel. After analyzing the properties of the transmitter, the channel and the receiver, the information theoretical capacity concerning asynchronous OCDMA is studied. Firstly, we model a discrete memoryless channel OCDMA system at the chip level, then we evaluate the aggregate capacity. By researching every noiseless capacity limit for some OCDMA codes, it is demonstrated that what limits the throughput is the number of available sequences. The results of our study indicate 2D (two-dimensional) codes can offer more sequences, therefore the performance is better.