Abstract:Throughput performance for Slotted ALOHA DS/CDMA (S-ALOHA-DS/CDMA) and Multicarrier Slotted ALOHA (MC-S-ALOHA) systems is performed and compared in this paper. Theory analysis and computer simulation results of throughput of S-ALOHA-DS/CDMA are obtained using different error correcting code. And comparison results with MC-S-ALOHA system are also obtained. It is proved that with the traffic increasing, the S-ALOHA-DS/CDMA with high error-correct code being used has better throughput performance. In the case of the too heavy traffic, the MC-S-ALOHA system has better throughput performance. If the total codes of the system are limited, the code contention collision will occur so that throughput will drop.