RSSI-based Object Finding System

Abstract

In this thesis, work regarding to development a system that would help finding lost objects based on RSSI is presented. The thesis gives a basic overview of the theory behind RF modulation, antennas and PCB design. Based on the presented theory, the technology and system parameters are chosen to design and ultimately complete the system. To improve the performace of the system the RF parts of the circuits are optimized using a vector network analyzer. As a result of this thesis a periodically transmitting battery-powered beacon that works at 433.92MHz is designed and completed. To read the transmitted data and the signal strength a receiver is also designed and completed to receive the data transmitted by the beacon and display the RSSI on a smart-phone screen using the micro-USB port.