Novel coexistence scheme between wireless sensor network and wireless LAN for HEMS

The problem of coexistence between IEEE 802.11g based wireless LANs (WLANs) and IEEE 802.15.4 based wireless sensor networks (WSNs) in the 2.4GHz band is an important issue for the operation of a home energy management system (HEMS) for smart grids. This paper proposes a novel coexistence scheme which is called a distributed active channel reservation for coexistence (DACROS) scheme to solve this problem. This scheme employs a hybrid-station (H-STA) that possesses two types of network device functions. The scheme improves the data transmission quality of the WSN devices which transmit energy management information such as power consumption. The proposed DACROS scheme uses the request-to-send (RTS) and clear-to-send (CTS) frames. These WLAN control frames are used exclusively to assign WSN system traffic resources. Theoretical analysis and computer simulation results show that the DACROS scheme decreases the beacon loss rate of the WSN to less than 1% when the WLAN system consists of ten stations (STAs) under saturated traffic conditions.