Changes to a standard's specifications might not be the most exciting news on the market, but when there's a chance to get more speed from a device without major replacements, the story is very different. That's the case with the 802.11ac standard, which has entered its Phase 2 of certification, incorporating MU-MIMO support, doubling the channel bandwidth, and increasing the number of channels in the 5 GHz band.
The debate over WiFi performance remains as relevant as ever, but over time we've seen different strategies aimed at improving wireless connectivity. Some manufacturers opted for brute force, increasing the number of antennas and power in their routers, while others believe the ideal solution lies in software, with precise optimizations to reduce congestion and improve the stability of each link. Meanwhile, the WiFi Alliance announced an official expansion of its certification under the 802.11ac standard, promising greater streaming capacity to multiple devices simultaneously and multi-gigabit speeds.
MU-MIMO and wider channels
By far, the most attractive aspect of this new phase for WiFi ac is MU-MIMO support, or “Multi-User, Multiple-Input, Multiple-Output”. In relaxed terms, MU-MIMO performs a kind of much more efficient multitasking, sending data streams to three or more devices simultaneously without having to “jump” from one to another. This prevents the router from “choking” in demanding streaming situations, with Netflix in HD being the most cited example. Phase 2 of WiFi ac also doubles the channel bandwidth, from 80 to 160 MHz, which, combined with the new quad-stream mode (the first certification offers tri-stream), presents a maximum theoretical bitrate of 3.46 gigabits per second. From a technical standpoint, WiFi ac could double that bitrate with eight streams, but the new certification reaches four, for now.
More channels in the 5 GHz band
Finally, the new WiFi ac increases the number of channels in the 5 GHz band. As more users switch to 5 GHz to avoid the chaos of 2.4 GHz, a greater number of channels reduces the risk of interference (read “many routers shouting on the same channel”) and optimizes spectrum usage. The list of routers certified under the new phase doesn't reach half a dozen according to the official announcement. However, there's a possibility, albeit remote, that certain high-end routers receive a firmware update incorporating some of these improvements. Of course, the rest of the devices will have to follow a similar path.
