Maximizing The Lifetime Of Wireless Sensor Networks In Trains For Monitoring Long-Distance Goods Transportation

As the technology of sensor and communication developing, wireless sensor networks (WSNs) have been widely deployed in many real applications. How to optimize the energy consumption of sensor nodes or how to prolong the lifetime of a WSN is one of the most important issues in WSN. Because most sensor nodes are powered by battery, the limited energy supply is one crucial factor restricting WSN’s life time.This thesis focuses on the life time maximization problem of WSNs deployed in trains for long-distance goods transportation. We set WSNs in trains to monitor the goods (such as cigarette, cotton and grain) conditions (e.g. temperature, humidity). These trains usually transport a large amount of goods for a long distance and for a long time, and the sensor nodes in boxcars are powered by batteries since there is no other power supply there. So the WSN’s life time maximization problem for long-distance transportation trains is urgent to be solved.We study the problem above to minimize energy consumption of each sensor nodes, and to maximize life time of the whole WSN in a train. In the thesis, we first formulate the network’s life time maximization problem as a MILP(mixed integer linear programming) problem, then we propose three heuristic routing algorithm:naive, poly and pseudo-poly algorithm. Finally, we conduct extensive experiment and the result shows that the performance of pseudo-poly algorithm is nearly same as the optimal solution, and is the most stable one among all the three algorithms. In conclusion, the pseudo-poly algorithm can significantly improve the life time of WSN in long-distance transportation trains.