Analysis of Wi-Fi received signal strength indicator as observed

Abstract

The last couple of years have witnessed tremendous growth in wireless communications. The quest for mobility of devices while maintaining seamless connectivity with a network has been a major driving force in the wireless technology industry. This has led to the introduction of various wireless standards such as WiMax, 3G/4G, MAN, Bluetooth and Wi-Fi to name a few. With Wi-Fi rising in popularity due to its increasing preference as last mile technology, we often witness the short comings first hand. These short comings many times are in the form of signal strengths as Wi-Fi operates in the unlicensed spectrum which is largely over-crowed by many devices and are major sources of interference. This thesis provides an overview of the received signal strength indicator (RSSI) of Wi-Fi signals and then employs it as a basis for comparing the behaviour of signals at peak and off-peak periods. The peak and off-peak periods have been defined by the number of people in the areas considered. inSSIDer software was used in signal logging and MATLAB was extensively used for both programming and analysis. All of these were done with the aim of establishing a pattern for Wi-Fi RSSI behaviour at peak and off-periods. Relevant techniques used in data analysis for signals were discussed in details stating why each was used. The results confirm that RSSI behaves differently under different physical conditions. Peaks signals were observed to be about 5dBm poorer than their off-peak measurements. It was also discovered that it is possible to relate attributes of the signal plot to the conditions of the physical environment. This thesis also provides recommendations on how the results produced may be used to improve existing structures and systems.