PHY-MAC Cross Layer Issues for QoS Provisioning in Wireless Ad Hoc Networks

Power conservation for maximizing the lifetime of the limited battery powered ad hoc networks are one of the most important factors in a network design. Transmitting at high power may assure the network connectivity, but sacrifices its lifetime and increases the interference as well. Meanwhile transmitting at lower power reduces the interference at the expense of network robustness. We investigate the minimum transmitted power to optimize those goals while considering the effect of several network design parameters such as the data rate, node spatial density and traffic load. This was done considering a cross layer design guidelines between physical (PHY) and Medium Access Control (MAC) layers to show how they are related and strongly affect the power consumption. Furthermore, considering the route QoS in terms of a given acceptable probability of error at the end of a multi-hop route.