Wi-Fi 6 is a further evolution and extension of the wireless LAN protocol itself after the Wi-Fi 5, and its initial naming code is HEW (High Efficiency WLAN). The design idea of Wi-Fi 6 is different from that of traditional Wi-Fi. In the past, the development of Wi-Fi protocol mainly focused on providing higher peak rates. As can be seen from the protocol name “High Efficiency”, Wi-Fi 6 pays more attention to efficiency, and hopes to use the current spectrum resources more efficiently, so as to provide higher actual network rate
To this end, Wi-Fi 6 introduces new technologies such as OFDMA, uplink MU-MIMO, TWT, target wake time, bss shader mechanism, and 1024-QAM.
0FDMA 0FDMA is an evolution from OFDM that was first used in cellular communications, and the Wi-Fi 6 standard has also adopted this technology to improve the efficiency of spectrum utilization. In the traditional approach, data sent by each user (regardless of packet size) consumes the entire channel. OFDMA divides a channel into multiple subcarriers and takes the smallest subchannel as a ResourceUnit (RU). In Wi-Fi 6, the minimum RU bandwidth is 2MHz, and users' data is carried on each RU. Taking 20MHz bandwidth as an example, up to 9 RU can be accommodated through OFDMA technology, and the remaining space is used as the protection interval. For example, a bus (20 MHz bandwidth) that previously carried only one passenger at a time can now carry up to nine passengers at a time (nine concurrent users).
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