Link Rate Allocation under Bandwidth and Energy Constraints in Sensor Networks

In sensor networks, both energy and bandwidth are scarce resources. In the past, the energy efficient routing problem has been vastly studied in order to maximize network lifetime, but link bandwidth has been optimistically assumed to be abundant. As energy constraint affects how data should be routed, link bandwidth also affects not just the routing topology but also the allowed data rate on each link, which in turn affects lifetime. Previous works that focus on energy efficient operations in sensor networks with the sole objective of maximizing network lifetime only consider the energy constraint and ignore the bandwidth constraint. This article shows how infeasible these solutions could be if bandwidth does become a constraint, then provides a new mathematical model to tackle both energy and bandwidth constraints. Two efficient heuristics are proposed based on this model; Simulation results show these heuristics provide more feasible routing solutions than previous works, and provide significant improvement on throughput.