Study of varying topology and nodes mobility for clustered CDMA wireless ad hoc networks

A mobile ad hoc network (MANET) is a collection of mobile hosts forming a temporary network on the fly, without using any fixed infrastructure. Characteristics of MANETs are thus a lack of central coordination, the mobility of hosts and a dynamically varying network topology. A multi-hop wireless ad hoc network is considered, where all nodes share a common channel and code division multiple access (CDMA) is used to facilitate concurrent transmissions. The network model consists of groups of nodes, termed as clusters. We address the question of how to efficiently facilitate intra-cluster and inter-cluster communications between multiple source-destination pairs. The influence of a change in cluster topology is also considered, and we study the effect of the node mobility in ad hoc networks. The used performance metrics is throughput per unit power. The concurrent transmissions employ distributed power control and are scheduled to resolve conflicts. A dynamic forwarding mechanism is used, in which forwarding nodes are used when it is energy efficient, and the choice of forwarding node varies according to source destination pairs. We compare the fixed topology and the varying topology for two example clusters. We also study the effect of node mobility by move one node in each cluster in two moving methods: random walk, and move in area node.