Power saving access points for IEEE 802.11 wireless network infrastructure

In the past decade there has been a huge proliferation of wireless local area networks (WLANs) based on the IEEE 802.11 WLAN standard. As 802.11 connectivity becomes more ubiquitous, multi-hop communications is increasingly used for range extension and coverage enhancement purposes. In this paper we present a design for an IEEE 802.11-based power saving access point (PSAP), intended for use in multi-hop battery and solar/battery powered applications. These types of APs have many practical applications and can be deployed very quickly and inexpensively to provide coverage enhancement in situations such as campuses, building complexes and fast deployment scenarios. Unlike conventional wired access points, in this type of system power saving on the AP itself is an important objective. A key design constraint is that the proposed PSAP be backward compatible to a wide range of legacy IEEE 802.11 end stations and existing wired access points. In this paper we describe the protocols required to achieve this compatibility, show the constraints imposed by this restriction, and present performance results for the proposed system.