Asynchronous bipolar-equivalent optical CDMA

We analyze the use of the bipolar-equivalent coding method in a incoherent fiber optic time-encoded CDMA communication system in an attempt to emulate the behavior of a coherent bipolar system. Specifically, we consider two possible asynchronous versions of the system which we refer to as appended and interleaved. We then describe a unified theoretical analysis for these systems based on the average interference parameter and the signal-to-noise ratio. We then consider the performance of the appended and interleaved systems and compare them to the performance of similar bipolar systems using length-127 m-sequences and Gold codes. We find that interleaving performs best of the methods considered--performance is very similar to the bipolar system we were trying to emulate, except for a factor of two increase in bandwidth requirement