Modeling and Simulating the Impact of Physical Propagation Environment on Ad Hoc Network Routing Protocols

In this paper, we will address the issues of modeling and simulating wireless ad hoc network and illustrate the impact of physical propagation model on ad hoc network routing protocol. The dynamic wireless channel is modeled with log-distance path loss model and log-normal shadow model. Further we will implement Rayleigh fading model to represent fading due to Doppler's effect caused by relative movement between the nodes. We will show that the performance of typical routing protocol such as OLSR significantly depends on the wireless channel through simulation in two different environments: open_environment characterized by open area and city_environment characterized by urban environment. The simulation results will show that the network degrades and the average delay and the routing packet overhead significantly increases in a higher attenuating environment such as the city_environment.