Pre-Emptive Channel Assignment Scheme with Fair Queue Scheduling in Evolving Mobile Networks

摘要

Due to rapid evolution in Mobile Cellular Industry (MCI) there is an increase in complexity when using mobility management techniques during the design, commissioning and operations of mobile networks. 1G methodology can no longer be adopted or applied for 2G and/or 3G mobile networks. Therefore, existing mobility management techniques need to evolve with the technological evolution in mobile networks which is offering different multimedia based services using internet and various other class based traffic as opposed to only conventional voice telephony with guaranteed Quality of Service (QoS) to the end user. Channel assignment schemes are key to the mobility management. In the literature, different channel assignment schemes have been devised for handovers occurring during multimedia based calls. We propose pre-emptive channel assignment scheme with fair queue scheduling based on buffer occupancy under certain QoS constraints in this paper. The proposed scheme is evaluated in a simulation environment and three different complex models/scenarios are used to validate the results. The multimedia traffic has been modelled by using MMPP (Markov Modulated Poisson Process) whereas we use conventional Poisson Process to model the voice calls. The performance study shows that the proposed preemptive channel assignment scheme results in reduced dropping probability at higher handoff rates as compared to other channel reservation schemes and demonstrates how the performance trade off is obtained in terms of call dropping, call blocking and mean queue lenghts.