WIFI6

On September 16, 2019, the Wi-Fi Alliance announced the launch of the Wi-Fi 6 certification program. The program aims to bring devices using the next generation 802.11ax Wi-Fi wireless communication technology up to standard.

5G has three scenarios of eMBB, mMTC and URLLC, and is oriented to future 4K/8K, VR/AR and other high-bandwidth video services and Internet of everything, while Wi-Fi 6 is in the same direction as 5G:

•Wi-Fi 6 supports multi-user concurrency at high rates, enabling ultra hd video applications in densely populated scenarios such as homes, stadiums and other public places.

•Wi-Fi 6 optimizes device power consumption and coverage capabilities to better support iot applications such as smart homes and smart cities.

Compared with Wi-Fi 5, Wi-Fi 6 mainly introduces the following new technologies:

OFDMA: Unlike Wi-Fi 5, which uses OFDM technology, Wi-Fi 6 borrowings the OFDMA technology used in cellular networks. Multiple terminals can transmit data in parallel at the same time without queuing and competing with each other, thus improving efficiency and reducing latency.

OFDM: A terminal occupies the entire wireless channel in each period when uploading or downloading data.

OFDMA: OFDMA wireless channel in frequency domain division multiple sub channel (a carrier), to form the time-frequency resources, user data bearing on each resource block, rather than to take up the whole channel, so as to realize multiple users at the same time parallel transmission inside each time period, not waiting in line, competing with each other, enhance the efficiency, reducing the queuing delay.

It is estimated that by 2020, a typical home will have 50 wirelessly connected devices. Wi-fi 6 introduces flexible OFDMA technology, which can support wireless access of a home's doorbell, refrigerator, light bulb and many other devices.

Lift coverage

As with cellular networks, the bottleneck in wireless coverage is up. In Wi-Fi network, AP usually has higher transmitting power, more antennas, and longer downlink coverage distance. Meanwhile, AP stays plugged into power supply and does not have to worry about power consumption. But for phones, tablets, and other iot terminals, the number of transmitting power and antennas is limited, affecting uplink coverage, while battery life must be optimized.

To this end, Wi-Fi 6 optimizes signal uplink coverage in a similar way to the NB-iot technology, in that the terminal concentrates its energy in a narrower 2MHz channel to improve uplink coverage by increasing the spectrum density of uplink power.

Wi-fi 6 expands its coverage, which helps it move from indoor to outdoor, paving the way for future deployment of campus iot, smart city and so on.