Fixed and adaptive blocking thresholds in CDMA cellular networks

A number of papers have shown that, in a code-division multiple access cellular network, bursty user mobility causes remarkable negative effects on link availability, and hence on cellular network capacity. This article shows that a possible provision for contrasting such negative effects is the introduction of a blocking threshold which produces an increase in the link availability and a decrease in the dropping probability at the expense of the appearance of a non-null blocking probability. In order to maximize the capacity of the cellular network, the blocking threshold has to be selected so that a proper balancing of the blocking probability, dropping probability, and link availability is achieved. In particular, the article presents a simple self-adaptive mechanism for selecting the blocking threshold, which achieves good performance and has the fundamental advantage of not requiring any a priori knowledge of the system parameters.