Routing Algorithm In WSNs With Mobile Sink

Although wireless sensor networks (WSNs)originated in the military field, with the high-speed development of Internet technology, embedded computing technology, sensor technology, Micro-Electro-Mechanism System(MEMS) technology, modern network technology, distributed information processing technology and wireless communication technology, the sensor nodes with computing power, wireless communication capability, battery power and storage capacity have become more and more inexpensive. Recently, WSNs has attracted wide attention in the world and it is widely used in the building condition monitoring, health care, environmental monitoring, traffic monitoring, smart home, space exploration, as well as large industrial factory and airport safety monitoring. WSNs has become a hot spot in the field of frontier, which involves sensors, embedded and wireless communication technology. However, the sensor nodes of WSNs have more limited communication capabilities and energy compared to the traditional network nodes. In wireless sensor networks, a key factor is how to effectively balance each sensor node’s energy consumption and prolong the life cycle of the whole network. While in traditional wireless sensor networks, the sink node’s location is fixed, all packets are sent to the only one static sink through the funnel-shaped (n to1) multi-hop routing, sensor nodes near the sink become bottleneck nodes easily because they have to forward all the data from other nodes that are away from the sink and they will be exhausted easily because of high traffic load. The sensor nodes may have empty energy, which causes the "energy-hole" and the whole network premature death. In recent years, researchers have put forward in wireless sensor networks using mobility methods and verify it can improve the performance of network. Researchers studied the mobility methods from many aspects:some actual deployment system, routing analysis and energy. Aiming at application problems of the wireless sensor networks with mobile sink, we research mobile sink network clustering and mobile sink routing algorithm.Firstly, because sensor nodes of wireless sensor networks have limited computing power and communication ability, it is requested to design network topology which can improve the performance of wireless sensor networks. K-Means algorithm is a kind of clustering algorithm and it can cluster the wireless sensor networks according to their geographical locations. K-Means algorithm can be used in wireless sensor networks, but it needs to be improved. This paper improved K-Means algorithm and proposed EK-means.Secondly, the paper presents an Energy-Efficient Mobile Sink Routing Algorithm (EEMSRA) for wireless sensor networks. This algorithm uses cluster-based model to implement the mobile sink routing protocol, and the sink moves based on the average energy in each cluster. The mobile sink can collects data of the sensor nodes in the cluster which is visited. Simulation results indicate that the proposed EEMSRA (an Energy-Efficient Mobile Sink Routing Algorithm) is energy efficient and energy balanced, it can provide longer lifetime as compared to other algorithms.