Low-Power Sleep Mode and Out-Of-Band Wake-Up for Indoor Access Points

Abstract

The expected massive adoption of indoor Access Points requires specific solutions to meet requirements for eco-sustainability regarding consumed power and radio interferences. Since Access Points are unused the main part of the day, application of a sleep mode mechanism is a promising approach. However, its implementation represents a radical change in mobile networking paradigm and requires innovative mechanisms to wake up the Access Points and thus rapidly restore the connectivity.Our approach uses an auxiliary low-power radio to carry out-of-band control information to maintain connectivity and wake up the Access Points when necessary. The paper details the software and hardware architecture as well as the prototyping results on Wi-Fi technology.

Sleep-enabled roadside units for motorway vehicular networks

“…A number of studies showed that by considering a sleep strategy at a node during its inactivity, a certain amount of energy can be saved [2], [5], [9], [12], [13], [14], [15].…”

“…operational power [24] Min. operational power [5] Transmit power [5] Energy for wake-up overhead [9] (42) Using Little's Theorem, the average packet delay is obtained as (43) Since a fraction of the arrivals is blocked due to the buffer overflow at the RSU, the utilisation of the system can be obtained as…”

“…However, further operational energy savings in an RSU/BS may be possible by utilising sleep mechanisms, where the transmitting circuitry is switched off to set the transceiver into low energy state [4], [5], [6], [7]. Such sleep strategies could be impractical for 'base station only' scenarios due to the large coverage, long resource activation time and high overheads that may arise from the ping-pong effect of consistently turning a BS ON and OFF [8].…”

Study of a Wake Up Radio Architecture for Home Multimedia Networks

“…For example, in the case of Linksys WRG54G Wi-Fi access point (AP), the maximum reduction in the energy consumption that can be achieved is 28.57 % [2]. This value represents the energy consumption of Wi-Fi interface compared to the entire energy consumption of the access point.…”

“…In [2]. A low power sleep mode and an out of band wake-up mechanism has been adopted, a low power radio module to carry out of band control information is used to switch the WiFi AP into the sleep mode when no users exist.…”