Hot-spot behavior of DCA wireless networks

Dynamic channel allocation policy (DCA) in wireless networks is known to be better than the fixed channel allocation (FCA) policy from the aspect of the call level QoS such as handoff dropping probability. Because of this, DCA networks are usually designed without the call admission control (CAC). However, given the decrease of cell sizes, channel borrowing may not be sufficient to cope with the hot-spot area size and its traffic intensity. This paper analyses the performance of the DCA networks with and without the CAC under the hot-spot traffic regime. We show that, under such conditions, a pure DCA network fails to ensure sufficiently low level of QoS in both the hot-spot area and the surrounding cells. We propose a CAC policy which can stabilize the QoS under nonuniform traffic, and which can be easily integrated in distributed DCA policies.