Wireless Sensor Network nodes performance measurements and RSSI evaluation

Wireless sensors are widely used in applications where small amount of data need to be transmitted over distances not exceeding several tens of meters, with low energy requirements. From the definition, the RSSI is the relative received signal strength in a wireless environment. There is a direct link between the RF power level received by one node and the RSSI indication. We used for the measurements a setup with nine wireless sensor nodes and one central coordinating node. For the results not to be affected by the ambient electromagnetic noise or other radio frequency emissions, all the measurements where made in a semi-anechoic chamber. We present an evaluation of the RSSI and describe the methods and procedures we used for the measurements in order to be able to compare the RF received signal power and the RSSI. Conclusions and future works are presented at the end of the paper.