"The first generation Wi-Fi launched 15 years ago brought forth wireless LAN (WLAN) applications, and the newer Wi-Fi standards that ensued have been providing faster transmission to notebooks, smartphones, and tablets. Over the past few years, Wi-Fi has even become available to consumer electronics and peripherals.
In terms of the emerging home applications, however, Wi-Fi 802.11g and 802.11n in the existing 2.4GHz band can no longer meet the requirement for HD streaming video transmission. As a result, 5G Wi-Fi - faster than 1 Gbps - is forthcoming."
"From 2007 to 2011, the 4th-generation Wi-Fi 802.11n raised the limit to 600Mbps (4 channels). The current limit is 450Mbps (3 channels). The 5G Wi-Fi 802.11ac launched in 2012 enables single-channel transmission at 450Mbps, three times of 150Mbps of 802.11n. At present, 802.11ac supports four MIMO channels (1.8Gbps) and will support up to eight MIMO channels. Therefore, the mainstream design of three transreceiver antennas for MIMO may reach 1.35Gbps. 5G Wi-Fi 802.11ac is also compatible with 802.11n (2.4GHz/5Ghz)."