Adaptive transmission power control in CDMA slotted-ALOHA radio communications

This paper proposes an adaptive transmission power control method for CDMA slotted-ALOHA systems. This method adaptively controls the target received power at base stations according to the offered channel load and the location of mobile stations. Computer simulation validates the effectiveness of this method: the capture effect can be achieved under heavy channel loads and therefore throughput performances are improved. Detailed evaluations of throughput and transmission delay in the case of perfect and imperfect power control are presented. Calculated results show that the proposed method has superior characteristics and can expand the allowable load area