英文摘要 |
For the sea surface salinity (SSS) applications, the data collected by the floats needs to be uploaded as a satellite passes through. The floats distributed on sea surface are equipped with sensors to measure interested information to deliver to visible satellites passing through the sky. The architecture can be divided into three subsystems, the satellite, the Argo float sensors and the data center. In this paper, we evaluate the performance of the self-coupled time synchronization protocol in the subsystem “Argo float sensors”. The basic idea is to achieve global synchronization through local pulse coupling. We will discuss the effect of various network parameters such as the degree of the node and the network diameter to the performance of the self-coupled mechanism. Furthermore, we will propose an improvement over this scheme in the paper. It reduces its message complexity by randomly turning on and off the sensor nodes for synchronization. We find that the self-coupled time synchronization protocol can achieve synchronization unless the network is sparse. It exhibits good cost-performance characteristics especially in the network environment of a great number of sensor nodes. Integrating with the proposed improvement, time synchronization can be effectively and economically reached as we will demonstrated in the paper. |