Open Access

A Power-Efficient Access Point Operation for Infrastructure Basic Service Set in IEEE 802.11 MAC Protocol

EURASIP Journal on Wireless Communications and Networking20062006:063728

DOI: 10.1155/WCN/2006/63728

Received: 19 December 2005

Accepted: 26 May 2006

Published: 19 September 2006


Infrastructure-based wireless LAN technology has been widely used in today's personal communication environment. Power efficiency and battery management have been the center of attention in the design of handheld devices with wireless LAN capability. In this paper, a hybrid protocol named improved PCF operation is proposed, which intelligently chooses the access point- (AP-) assisted DCF (distributed coordinator function) and enhanced PCF (point coordinator function) transmission mechanism of IEEE 802.11 protocol in an infrastructure-based wireless LAN environment. Received signal strength indicator (RSSI) is used to determine the tradeoff between direct mobile-to-mobile transmission and transmission routed by AP. Based on the estimation, mobile stations can efficiently communicate directly instead of being routed through AP if they are in the vicinity of each other. Furthermore, a smart AP protocol is proposed as extension to the improved PCF operation by utilizing the historical end-to-end delay information to decide the waking up time of mobile stations. Simulation results show that using the proposed protocol, energy consumption of mobile devices can be reduced at the cost of slightly longer end-to-end packet delay compared to traditional IEEE 802.11 PCF protocol. However, in a non-time-critical environment, this option can significantly prolong the operation time of mobile devices.


Authors’ Affiliations

School of Computer Engineering, Nanyang Technological University


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© Ye Ming Hua et al. 2006

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