The topological characteristics of an IEEE 802.16 mesh network including the tree’s depth and degree of its nodes affect the delay and throughput of the network.To reach the desired trade-off between delay and throughput,all potential trees should be explored to obtain a tree with the proper topology.Since the number of extractable tree topologies from a given network graph is enormous,we use a genetic algorithm(GA) to explore the search space and find a good enough trade-off between per-node,as well as network-wide delay and throughput.In the proposed GA approach,we use the Pruefer code tree representation followed by novel genetic operators.First,for each individual tree topology,we obtain expressions analytically for per-node delay and throughput.Based on the required quality of service,the obtained expressions are invoked in the computation of fitness functions for the genetic approach.Using a proper fitness function,the proposed algorithm is able to find the intended trees while different constraints on delay and throughput of each node are imposed.Employing a GA approach leads to the exploration of this extremely wide search space in a reasonably short time,which results in overall scalability and accuracy of the proposed tree exploration algorithm.
