–Call admission control (CAC) is essential to guarantee the signal quality in CDMA systems. Signal-tointerference-and-noise ratio (SINR) is used as a criterion for user admission by comparing the SINR with a predefined threshold value (SINRth). The choice of the SINRth value is restricted by two opposing factors: the signal quality and the network utilization. Setting SINRth at high value is desirable to increase the signal quality. However, SINRth shouldn’t exceed a certain limit to keep the blocking probability (Pb) below a maximum value. In this paper, we derive an upper bound of SINRth (SINRth-ub) for multi-class CDMA systems with imperfect power control. SINRth-ub of class i (SINRth-ub(i), i=1, 2,…., L) is determined by finding the relationship between the blocking probability of all classes and SINRth(i). Then, SINRthub(i) is determined as the highest value of SINRth(i) that keeps the blocking probability of all classes below the corresponding maximum values. Keywords–Cal...
Mahmoud El-Sayes, Mohamed H. Ahmed