时隙ALOHA DS/CDMA系统与多载波时隙ALOHA系统吞吐性能的比较研究

COMPARISON STUDY OF THROUGHPUT PERFORMANCE IN SLOTTED ALOHA DS/CDMA AND MULTICARRIER SLOTTED ALOHA SYSTEMS

该文对同样带宽下时隙 ALOHA DS/CDMA系统和多载波时隙 ALOHA系统的吞吐量进行了理论计算、比较和仿真。结果表明,在总负载较大时,采用高纠错能力的时隙 ALOHA DS/CDMA系统可以在吞吐量上有更好的性能。但若网络负载过重,时隙ALOHA DS/CDMA系统的吞吐性能较多载波时隙ALOHA的系统下降快;码字总数受限会带来码字选择的冲突,从而降低系统的吞吐性能。

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.