Battery lifetime performance of Wi-Fi enabled sensors

IEEE 802.11 standard was originally designed for high bandwidth applications targeting consumer electronics market. Hence, it was not considered as a feasible technology for wireless sensor networking applications. Recently, due to the growing market potential for smart objects with IP connectivity, several companies introduced low-power Wi-Fi products optimized for sensing applications. Wi-Fi brings many advantages for IP enabled sensors such as easy integration with existing infrastructure, built-in IP-network compatibility and familiar protocols and management tools. However, multiple years battery lifetime requirement for sensors remains as the main concern. In this paper, we evaluate the battery lifetime performance of a Wi-Fi sensor for a given scenario and investigate the impact of packet size, data rate, application code size, security schemes and MAC layer retransmissions on battery lifetime.