S-WOW: Signature based Wake-on-WLAN

Long distance Wi-Fi links are cost effective alternative to provide Internet and VoIP connectivity, in rural areas. In developing regions these low cost solutions have a challenge of an irregular power supply. In prior research Wake-on-WLAN has been proposed as a way of reducing power consumption by using low power sensor nodes to reduce the duty cycle of the more energy consuming Wi-Fi devices at a node. These sensor nodes wake-up the Wi-Fi device at the link node on receiving 802.11 traffic from neighboring link. The current Wake-on-WLAN implementation scheme suffers with false wake-up due to channel activity generated from noise in the operating frequency of the sensor node. In this work we devise a signature based wake-up mechanism called S-WOW, to avoid the false wake-ups. This is challenging as the sender and the receiver of a signature pattern at a link are operating with heterogeneous radios. Our scheme is robust enough to work in presence of periodic or non-periodic impulsive noise as well as prevents false wake-up when the channel is filled with (noise) energy.