A mobile controlled algorithm for improving the throughput in aS-ALOHA DS-CDMA system

摘要

This paper presents a novel adaptive DS-CDMA slotted-ALOHA packetrandom access scheme with transmitter-based spreading codes for mobiles.It is aimed at improving the throughput and message delay delivery whentraffic load values below the saturation point of the conventionalDS-CDMA slotted-ALOHA system are sensed in the channel. For this purposea mobile assisted algorithm is envisaged to control the change of thetransmission rate according to the traffic load. This algorithm revealedthat the optimum behavior, obtained using a Markov chain model, may bealmost reached at a low complexity cost. Moreover, priorities betweenmobiles could be easily established. Finally, a traffic model based on arealistic statistical length distribution of the messages illustrateshow the delay delivery can be greatly reduced