Caracterização do desempenho RF de protótipo para RSSF de longo alcance com aplicação em smart grid

Abstract

In this master’s thesis, it is done a profilement of the radio frequency (RF) performance response, of a prototyped sensor node/sink node for a Wireless Sensor Network (WSN), on the application of Smart Grids (SG). This prototype uses the 868-915 MHz frequency band and features LoRa® modulation. Power transformer monitoring is a field of application in Smart Grids. We chose to monitor temperature and vibration. Those parameters are related, respectively, to the lifetime and mechanical failures in power transformers. The Free Space Transmission Equation proposed by Friis was chosen to profile the radio performance. Correlated works found in the literatureprovided guidance in the proposed methodology. The sensor node is composed of temperature and vibration sensors, a microcontroller and an RF module. The prototype uses less than 120 mW (average power) in a scenario where a transmission of 768 bits occurs every 68 s. The measured results show communication ranges up to 1000 m with 99% packet reception rate, over an urban environment of a University Campus. It is estimed 3450 m for the communication range, compatible with the found in literature.