IEEE 802.11 is the mainstream standard for WLAN. Supported by the continued growth of smart handheld device market, shipment volume of Wi-Fi connected devices based on this standard is expected to reach four billion units in 2019. In line with the availability of new IEEE standards, Wi-Fi chip vendors and branded equipment manufacturers have constantly upgraded their products and launched new application devices. Furthermore, the development of IoT in different industries has become clearer, steering the direction of the WLAN industry. Among the WLAN industry sectors, wearable devices, smart home, and public Wi-Fi hotspots have received significant attention.