An ACO-based Routing Protocol For Wireless Sensor Networks

With the development of information technology, wireless sensor network (WSN) becomes a new research field, which based on wireless telecommunication technology, computer system and micro-motor system. As an inter-disciplinary subject, WSNs involve many fields such as computer, microelectronics, sensor, network, telecommunication, signal processing and so on, which can be used for sensing, collecting and processing information of monitored objects, then sending them to the users.WSNs consist of numerous minor sensor nodes which have limited energy. Under normal conditions, their batteries are not feasible to be replaced. The technology of using renewable energies like solar energy and wind energy is immature, which can't meet the demands of large-scale applications. Therefore, optimizing routing protocols and improving routing policies are the only feasible way to prolong network service life. It is an important research issue in WSNs.In recent years, many foreign and domestic scholars have proposed a great number of improved routing protocols for WSNs. However, most of the improvements focus on rising network service quality but neglect energy consumption of the nodes. With the occurrence of various intelligent algorithms, more and more scholars apply them to the research of WSN routing protocol. The way that the ants find food is very similar to the way by which the nodes seek the paths. Thus, many routing protocols based on ant colony algorithm have been proposed one after another. Additionally, as ant colony algorithm is an intelligent algorithm developed by ant colony cooperation behaviors, it has the inherently parallel characteristic, good organization and robustness. So it is gradually applied to routing protocol design for wireless sensor networks.We make a deep analysis and research on principles and features of ant colony algorithm. Based on the current research of routing protocol for WSN, especially those account of ant colony algorithm, which effectively combine good properties of ant colony algorithm with design requirements of routing protocol for WSN, we put forward a new routing protocol named MFABR (Multiple Factor Ant-based Routing Protocol).MFABR makes improvement in terms of ant data package structure, probability choice formula and pheromone factor renewing ways. It uses remaining energy level and data transmission distance as the heuristic factors and applies them to the ant pheromone consistence feedback value formula. At the same time, it can further optimize renewal rule of pheromone consistence feedback value in order to make the pheromone consistence of the whole network rapidly approach to Sink node and keep the selected routing position. Moreover, it can avoid partial routing deviation in the process of data message transmission, and finally reach the objective of saving network energy consumption and prolonging the whole network service life.By adoption of NS2simulation tool and MFABR protocol, we did lots of simulation experiments. On the tests under experimental scenes of different node scales and densities, the simulation proves that it holds good expansibility, evenly usage of node's energy and effectively prolongs the whole network service life.