MIPS: MIMO Power Save in 802.11n Wireless Networks
A fundamental limitation of applying MIMO in battery-constrained, 802.11n-enabled portable devices, is excessive power consumption of multiple active RF chains. The authors start the study in 802.11n MIMO power save (MIPS) by seeking to identify the factors that determine the most energy efficient chain setting. Surprisingly, the experimental results show that the fastest RF chain setting may not be the most energy efficient and the most power-hungry RF chain setting may not be the least energy efficient. The winner in fact derives from a unique interplay among MIMO gains, SNR, application data source rate, power consumption and can dynamically change in time.