Power control and fairness MAC mechanisms for 802.11 WLANs

Exploiting spatial reuse opportunities will allow more parallel transmissions and improve the throughput of wireless networks. Power control is one of the major mechanisms used to exploit both spatial reuse and power conservation opportunities. Increasing the transmitting power will prevent the receiver from interference but it will consume power and create additional interference to other communicating stations. On the contrary, reducing the transmitting power will reduce the interference to other communicating pairs and lessen the sender’s power consumption, but it will result to a lower signal to noise ratio (SNR) at receiver’s side. This article presents a power control MAC protocol that exploits the spatial reuse and power conservation opportunities for 802.11 Wireless LAN. The proposed protocol evaluates the interference and adopts a power control mechanism on both the sender and receiver sides to allow more communications to proceed simultaneously. In addition, a fairness control mechanism to reduce the average communication delay and alleviate the packet lost phenomenon is also proposed. Performance results reveal that the proposed protocol improves the throughput and power consumption of WLAN while the fairness among communicating pairs can also be maintained.