Proportion based protocols for load balancing and lifetime maximization in wireless sensor networks

This paper presents the problem of minimizing energy consumption and maximizing lifetime in a many-to-one sensor network. In such network pattern, all sensor nodes generate and send data to a single and fixed base station (BS), via multi-hop transmissions. When all the sensor data have to be forwarded to a single BS via multi-hop routing, the traffic pattern is highly non-uniform, putting a high burden on the sensor nodes close to the BS. Some strategies that balance the energy consumption of the nodes and ensure maximum network lifetime by balancing the load are proposed and analyzed. The key element of the research is the use of multiple transmission power levels. We studied an optimal solution for calculating the hop-by-hop traffic proportions for the particular case of nodes having just two transmission power levels, and compared the results given by the heuristics with those from the optimal analytical case. Another goal is to propose and implement a systematic approach for the construction of the sensor network based on real sensor nodes. The neighbor discovery phase, the way in which the BS finds out the network topology and than impose the strategy and decide whether the nodes to act locally or respect the instruction from the sink are part of the protocol that is described in the paper.