Reducing energy consumption on mobile devices with WiFi interfaces

Emergence of mobile handheld devices with WiFi (IEEE 802.11) interfaces such as WiFi phones, WiFi-cellular dual-mode phones and PDAs (personal digital assistants), allow users to take full advantages of heterogeneous radio technologies. WiFi, however, was not originally designed for energy-constrained handheld devices. As a result, the standby times of a handheld device with a WiFi interface is significantly lower than what people typically experience with today´s cellular phones. This paper presents and evaluates a system-level power management method devices with WiFi, or other high energy-consuming network interfaces, to significantly increase their standby times without modifications to WiFi and upper layer protocols and implementations.