The Research On Wireless Sensor Networks Data Transmission Technology Based On Network Coding

Wireless sensor networks consist of large amount of sensor nodes which organize and form a network system by themselves. It is characterized by large-scale deployment, resource-constrained, and self-organization. In recent years, it has caught more and more attention. And it has been widely applied to many areas, such as environment, health, home and so on. Sensor nodes generally have limited storage space and comput ing ability. What’s more, they have non-renewable energy. It’s energy consumption mainly has two aspects: receiving and sending packets. How to effectively manage packets transmission, save energy and improve reliability is always a hot topic in wireless sensor networks.Network coding has attracted wide attention in academic circle since it was proposed in 2000. It points out the research direction for the higher quality of data transmission in wireless sensor networks. Network coding is a new method of data transmission that breaks the traditional way of storing and forwarding. It allows intermediate nodes to encode received packets before forwarding. As long as the destination node receives enough packets, it can get original information through decoding operation. Existing researches show that using network coding in wireless sensor networks can improve the network throughput and reduce energy consumption.In this paper, we study the problem of low energy consumption and reliable data transmission based on the advantage of network coding. Firstly, we research how to effectively retransmit lost packets. During data dissemination, sensor nodes may not receive the whole packets because of unreliable link and sleep mode. It is necessary to retransmit the lost packets. Improper retransmission method may lead to higher energy consumption. We use network coding to propose an efficient retransmission algorithm which considers the factors about unreliable link and sleep mode. During the retransmission stage, this algorithm can make the value of recovery ratio at sink node reach the maximum. So it can reduce the number of transmissions and energy consumption. Then, we study the problem of data collection. Data collection is the main function of wireless sensor networks. Existing collection schemes are almost for the single collection mode. So we put forward an intelligent network coding collection protocol. Sensor nodes determine whether they should encode the received packets according to some indicators. This not only reduces the blindness of network coding, but also reduces the number of data transmissions.Simulation results show that our retransmission method can reduce average number of transmissions, improve tranmission efficiency and reduce energy consumption. What’s more, intelligent network coding data collection protocol allows two collection mode in a network system at the same time. The ideal of intelligent network coding can futher reduce and balance energy consumption.