An energy consumption model for 802.11ac access points

As the user traffic increases dramatically, wireless local area networks (WLANs) have been evolving to satisfy increasing traffic demands. IEEE 802.11ac, as the latest amendment to the family of WLAN standards, provides data rates on the order of 109. However, due to the large scale deployment of WLANs with such high speeds, their energy consumption has become a critical issue. In this paper, we present a comparative investigation of energy consumption of 802.11ac access point (AP) in a server-client based testbed by taking into account different parameters such as transmission bandwidth, transmit power level and packet length. We model the instantaneous data transmission rate and instantaneous power consumption of the access point with a bivariate normal distribution and obtain a model for the energy consumption per bit. We verify this generalized model, that provides insight about the energy consumption of the AP, with measurement results. Based on our measurement results we also conclude that the AP configurations should be determined according to the end-user traffic demand in order to increase the energy efficiency of the AP.