Experimental Evaluation of Coexistence Method for ZigBee under WLAN Interference
ZigBee has attracted attention for constructing the sensor network such as home energy management system. Both ZigBee and Wireless LAN (WLAN) use a 2.4GHz band, called the industrial, scientific and medical unlicensed band; therefore, ZigBee faces severe interference problems in the presence of WLAN. Frame collisions are serious problems between ZigBee and WLAN. Both employ a carrier sense mechanism to avoid collision, but both use different channel access mechanisms. The primary problem is the competition that exists between WLAN data frames and ZigBee ACK frames, i.e., because of WLAN interference, ZigBee may not receive any given ACK frame; therefore, the ZigBee transmission success ratio is degraded.