Call Blocking and Dropping in Sectorized Cellular Networks with Fractional Frequency Reuse

Inhalt:
This paper analyzes the probabilities of new-call blocking and handoff-call (HC) dropping for a sectorized cellular network with fractional frequency reuse (FFR). Since a sectorized FFR network (SFN) consists of two areas, the super group (SG) and the regular group (or sectors), three different types of HCs may happen when a mobile station (MS) moves from the SG to a sector, from a sector to the SG, or from one sector to another sector. We construct a model of Markov chains and derive the state transition rates. Then on the basis of the stationary probabilities of Markovian states, we derive the three types of block probabilities of new-calls and two types of dropping probabilities of handoff-calls. Finally, we conduct extensive numerical simulations. From the results of numerical simulations, we reveal two important rules for choosing the optimal radius of the SG, with which the system blocking and dropping probability can be minimized.