Research of SMS-Based Highly Distributed Data Acquisition System

This paper has presented a SMS (short message service)-based wireless solution for a highly distributed data acquisition system. This system is a three-hierarchy model. At the top level is a master station which acquires data from multiple slave stations distributed in a very wide area. These slave stations are considered at the middle level and they communicate with the master station by SMS through GSM network. Each slave station also acts as a master in its own local RS485 network to which several temperature detection modules are connected. These temperature detection modules are thought at the lowest level. This paper has analyzed the general structure of this whole system; focused on the hardware and software implementation of one of its most important parts: the slave station; and described the communication protocol between the slave station and the master station