Centralized transmission power scheduling in wireless sensor networks

Abstract

In a wireless sensor network (WSN), the tendency of data flows that congregate to a specific node (e.g., a sink) leads to the imbalance of traffic intensity, and presents challenges to prolonging the network lifetime. For the applications, which require that the lifetime of each node is almost same with each other and as long as possible, we propose a centralized transmission power scheduling scheme and its implementation. We introduce a transmission power-based locating and addressing scheme for sensors to acquire and express the global topology information. Based on the total energy of the sensor nodes in a unit, we introduce a global optimized power criteria (GOPC) with linear programming (LP). By applying GOPC to the location-based routing protocol, we propose the Routing Protocol under Global Optimized Power Criteria (RGOPC). Simulations show that RGOPC achieves superior performance in prolonging network lifetime, when compared with the minimum transmission energy (MTE) and direct communication (DTX) schemes. For the topology where the sink is far away from each sensor, the network lifetime with RGOPC is about 3.2 and 2.7 times that with MTE and DTX scheme, respectively. For the topology with sink in the center of the network, the lifetime with RGOPC is about 4.6 and 2.2 times that with MTE and DTX scheme. It is also shown that RGOPC incurs no more implementation cost compared with location-based routing protocol.