Beacon interval impacts on battery life
We've been experimenting lately with wireless clients having 802.11 power-save mode enabled and different access point beacon intervals. By increasing the beacon interval, clients will sleep longer and save battery power. To get a better idea of the savings, We ran some tests with the beacon interval set to 100 milliseconds (the default) and up to 5 seconds. We found beacon intervals at 1 second provide approximately 14 percent increase in battery life. Beacon intervals set beyond 1 second increased battery very slightly. So, it's probably worth setting the beacon interval out to around 1 second for clients implementing power-save mode. Just be certain that the longer beacon intervals don't negatively impact roaming.