Joint Rate and Power Adaptation for Wireless Local Area Networks in Nakagami Fading Channels

Abstract

In this paper, we propose a fast channel-driven rate and power adaptation (CDRPA) algorithm for wireless local area networks (WLAN). The proposed algorithm jointly adjusts the rate and power for data frame transmission in a generalized Nakagami fading channel. Different from the previous works, the CDRPA algorithm bases on the channel quality observed from the previous ACK frames and makes the selection only from the limited combinations of rate and power, instead of exhausted searching. Thus, the CDRPA algorithm greatly reduces the complexity compared to the previous approaches. Furthermore, to meat the different performance requirements, we propose several alternatives based on the CDRPA algorithm. From the viewpoint of energy saving, the CDRPA algorithm determines the transmit power first to maximize energy efficiency; while achieving the maximum goodput performance, the CDRPA first selects the appropriate transmit rate to ensure the successful transmissions. The numerical results show that the CDRPA algorithm can approach to the optimum performance in terms of energy efficiency and goodput while keeping the low complexity.