Research And Design Of The Satellite-Aided Data Collecting Scheme For Delay-Tolerant Wireless Sensor Networks

Wireless sensor networks have wide-range potential applications. It has been considered as one of the most important techniques of the 21th century, and has attracted a great deal of research interests in recent years. Data collection is the basic funtion of applications in wireless sensor networks. However, wireless sensor networks may not work effectively in the scenarios where no or extremely low connectivity exists due to sensor node's random deployment, sparse network density, sensor energy exhaustion and so on. This paper aims at the sparse wireless sensor network deployed in wide area. The satellite-aided delay-tolerant wireless sensor network scheme is designed, then the convex hull-based algorithm is proposed. It provides a candidate solution to the problem of data collection in sparse wireless sensor networks deployed in wide area and complex environments.(1) In order to solve the problem of data collection in sparse wireless sensor networks deployed in wide area, which is in remote complicated environment, we analyze some data collection models in wireless sensor networks and study the constraints of data collection in delay-tolerant wireless sensor networks, and then propose the satellite-aided architecture for delay-tolerant wireless sensor networks, which is based on the techniques of satellite communication and Data Mule. In this scheme, the management center sends instructions to target areas through satellite communication, then Data Mules collect data in the wireless sensor network and send the data back to the management center through satellite communication. This approach can solve the problems such as network connectivity, limited energy, remote communications.(2) In order to improve the efficiency of data collection, we study the problem of planning the movement path of Data Mule, and propose the convex hull-based algorithm for the problem, which can construct a cost-effective path for Data mules.(3) Based on the satellite-aided delay-tolerant wireless sensor network scheme, we design the message format, command types and protocol processes for DTSN-S communication protocol.(4) We establish the platform of experiments for the system, carry out the simulations of the system, and evaluate the efficiency of the convex hull-based data collection algorithm. The simulation results show that the algorithm improves the success rate of data transmission and reduces the network latency.