Power Save has always been a part of the 802.11 standard since 1999. The devices it had targeted were a lot different from the wireless devices used today. Back then these devices were primarily laptops with big batteries moving between conference rooms. No thought was made that Wi-Fi could and would be added to small hand held devices being used in all aspects of our life. With the addition of Wi-Fi to mobile devices like cell phones, the power save requirements have changed.
There is now a greater focus on power saving in Wi-Fi than any previous stage of its existence. The advancements in hardware and application have shaped the power save options available today in 802.11. Let’s look at the some of the techniques used to save power consumption.
There are four basic operations that a radio can perform that leads to power consumption. Power consumed by each activity increases in the given order (1-4). By controlling how long the radio operates between the below states, a user has some control on how much power his radio consumes.
- Idle & awake