Channel Allocation with Recovery Strategy in Wireless Networks

With the increasing penetration of wireless communications systems, customers are expecting the same level of service, reliability and performance from the wireless communication systems as the traditional wire-line networks. Due to the dynamic environment, such as the roaming of mobile subscribers, maintaining a high radio frequency (RF) availability is one of the most challenging aspects in wireless network management. To date, in wireless network management, a call is dropped when the channel it uses goes down. In order to increase system end-to-end availability, an RF channel recovery scheme is proposed in this paper. When an RF channel fails, the channel is replaced by another working channel and the call continues. The methods to replace failed RF channels of ongoing calls and to handle channel failures of handoff and new calls are investigated. Markov reward models are developed to compare system availability and performance. Automated generation and solution of Markov reward models is facilitated by a version of stochastic Petri nets that we call stochastic reward nets. The results show that the recovery scheme reduces the dropped calls and the blocked calls significantly under both light and normal traffics.