In this dissertation, we study resource allocation problems in cellular networks with multimedia services. In particular, we focus on the performance analysis of various resource allocation techniques for cellular network with multimedia services. We extend resource allocation technique proposed for voice-oriented cellular networks to one for cellular networks with multimedia services.
First, we develop an efficient approximation method (to be called reduced load approximation) for performance analysis of cellular networks with multimedia services and mixed platform types. To maintain hand-off priority and access regulation, we assume that system operates under trunk reservation policy. The correlation among cells due to hand-off traffic is expressed by rate equations, and the distribution of the number of busy channels for each cell in the network is approximated by one-dimensional recursion. This leads to a set of nonlinear fixed point equations which can be solved by repeated substitution. The computational complexity and memory requirements of proposed algorithm are linear so that we can use this algorithm to estimate performance measures of the cellular mobile network even for large size. We test the proposed approximations on a number of examples. Numerical results for two cells and five cells networks are given. The comparison between approximation and simulation results shows that the proposed fixed point approximation for blocking probability is quite accurate.
Second, we investigate the traffic performance of Channel Borrowing Without Locking (CBWL) schemes with multimedia services on non-homogeneous cellular network in which cut-off priority is given to handoff calls. We take into account two generic routing schemes analyzed: one is the randomized routing and the other is the least loaded routing. The performance measures are the new call blocking probabilities and the handoff failure probabilities. To evaluate blocking probabilities, we construct a generalized access network whose blocking probabilities are same as ones for CBWL systems. For analysis of generalized access network, we apply the reduced load approximation. The computational complexity and memory requirements of proposed algorithm are linear so that we can use this algorithm to approximate blocking probabilities of CBWL systems of large size. The propose approximations are tested on some examples. Numerical results for 12 cells and 36 cells networks are given. From the comparative analysis, we can see that the proposed approximation method is quite accurate.
Finally, we consider several reservation strategies incorporating aspects of complete sharing(CS) and complete partitioning(CP) policy. A part of the bandwidth is completely shared and the other part is completely partitioned. This allows more flexibility in catering to the QoS requirements of the different user types while maintaining higher network usage. Our work is an extension of reservation strategies for voice traffic to multimedia traffic in a wireless environment [12]. Our model permits the change of bandwidth of multimedia traffic on multi-bearer service with static priority which provides services to heterogeneous users who request service either as new or handoff users. We focus on the performance analysis of various reservation strategies over static priority. We give analytical models of proposed reservation policy and we investigate the approximation method of performance analysis for those systems.
