A Research On Relay Node Settings Algorithm In Wireless Sensor Networks

Wireless sensor network (WSN) is one of the core technologies in the internet of things, it has been widespread concerned by scholars at home and abroad in recent years. The placement of nodes is the foundation for networks operation in WSN, in general, the layout positions of gateway node and sensor nodes are relatively fixed owing to their function features. To guarantee networks'connectivity and reliability, some relay nodes are usually placed into WSN, so relay node placement is vital to the overall layout strategy, it determines the lifetime, communication efficiency and other indicators of WSN.Although the relay node placement of WSN has caused more and more attention, the researches of relay nodes placement lag far behind other aspects of WSN study. The existing relay node placement algorithms generally take the minimum number of relay nodes as the algorithm target, and many issues is ignored, such as relay node restricted placement areas, the communication capacity and the energy consumption of the whole networks. To address these problems, we studied the main work in this paper are as follows:1,Many constraint conditions were introduced into the existing model of survivable relay node placement, such as relay node restricted placement areas, the irreversible factor in the forwarding communication paths, the upper times of data transfer and the communication capacity of relay nodes. And we presented a new evaluation standard based on the minimum distance factor of communicating network. A hybrid relay node placement algorithm was implemented in solutions to complete the network initial relay node placement and the relay node adjustment and additional strategies because the new sensor nodes join into the current network, and the method was based on enumeration and greedy optimization algorithm. The simulation results demonstrate that the operable and optimized relay node placement algorithm proposed in this paper has an obvious improvement of energy-efficiencies, compared with other algorithms.2,The current data aggregation algorithms usually do not pay enough attention to the different data throughput of different network layers, so there may be a situation that is too late to complete the data transmission and data aggregation. Aiming at this problem, this paper proposes a relay node adaptive delay distribution algorithm for reliable transmission, and this adaptive algorithm schedules the waiting time for every relay node not only based on their position in the network, but also take the different data throughput of every node into account. At the same time, we take the compensation latency of MAC layer into the timing control strategy to reduce effectively the data collision. Analysis and simulation show it improves the energy efficiency of network and data return rates.3,This paper designed one wireless data transmission module based on CC2430, and tested their communications performance to provide real data for the previous research of relay node placement algorithm. At the same time, it provides the hardware test conditions for later verification in the real network environment. In addition, this paper designed a visual GUI man-machine operation interface except carrying out algorithm simulations.