New Call Blocking versus Hando � Blocking in Cellular Networks

In cellular networks blocking occurs when a base station has no free channel to allocate to a mobile user One distinguishes between two kinds of blocking the rst is called new call blocking and refers to blocking of new calls the second is called hando blocking and refers to blocking of ongoing calls due to the mobility of the users In this paper we rst provide explicit analytic expressions for the two kinds of blocking probabilities in two asymptotic regimes i e for very slow mobile users and for very fast mobile users and show the fundamental di erences between these blocking probabilities Next an approximation is introduced in order to capture the system behavior for moderate mobility The approximation is based on the idea of isolating a set of cells and having a simplifying assumption regarding the hando tra c into this set of cells while keeping the exact behavior of the tra c between cells in the set It is shown that a group of cells is enough to capture the di erence between the blocking probabilities of hando call attempts and new call attempts