Derivation of the probability of packet success for asynchronous DS/CDMA using random periodic spreading sequences

A method for deriving the probability of packet success of an asynchronous direct-sequence code-division multiple-access (DS/CDMA) system with random periodic spreading sequences is developed. Numerical results were obtained using Monte Carlo integration. It is shown, that a system employing random spreading codes performs considerably different than a system using random periodic spreading sequences. Both, scenarios with equal and unequal power levels at the receiver are investigated. As an example, slotted DS/CDMA-ALOHA with additional forward error correction (FEC) is analyzed. Results for effective packet throughput and network capacity are presented.