Capacity regions for wireless ad hoc networks

We define and study capacity regions for wireless ad hoc networks with an arbitrary number of nodes and topology. These regions describe the set of achievable rate combinations between all source-destination pairs in the network under various transmission strategies, such as variable-rate transmission, single hop or multihop routing, power control and successive interference cancellation. Multihop cellular networks and networks with energy constraints are studied as special cases. With slight modifications, the developed formulation can handle node mobility and time-varying flat fading channels. Numerical results indicate that multihop routing, the ability for concurrent transmissions, and successive interference cancellation significantly increase the capacity of ad hoc and multihop cellular networks. On the other hand, gains from power control are significant only when variablerate transmission is not used. Also, multihop routing greatly improves the capacity of networks with energy constraints. In all types of networks, capacity increases in time-varying flat fading channels or when nodes are moving. Index Terms ad hoc, wireless, multihop cellular, energy constraints, capacity region, multihop routing, mobility, flat fading ∗ Work supported by the Office of Naval Research (ONR) under grant number N00014-99-1-0698. Authors are with the Department of Electrical Engineering, Stanford University, Stanford, CA 94305-9515. 1