FCC Proposes Faster, Higher Capacity WiFi to Reduce Spectrum Crunch
In fact, 802.11ac routers don’t really operate at gigabit speeds, despite being theoretically capable. The reality is these devices are limited in what they can do. Right now, the only way to use 802.11ac is to buy two devices, a router and either a media bridge or another router to connect with wired Gigabit Ethernet. Even when a true 802.11ac connection is established, the real Layer 7 (that’s the application networking layer that you would use for streaming audio or video) throughput is more on the order of 300 to 400M bps or fewer depending on the distance between the devices, interference and other factors. But for WiFi to work even at these speeds, you need a MIMO antenna system that handles at least three spatial streams on both ends. These antennas take up a fair amount of space, a reason you don’t see them on your iPhone. What the FCC is proposing is really a larger number of 802.11ac channels, which in turn means a larger number of available 5 GHz channels. By having a greater number of channels, you’ll have less likelihood of WiFi congestion and you’ll be able to have more people using faster WiFi. But there are two things that will keep even this from happening right away. First, the only way these WiFi channels can be used is if the devices using them have a way to access the new channels. Right now, even devices that work with 802.11n are limited to existing channels. Perhaps some devices have radios that can be tuned to new frequencies through a software upgrade, but I suspect most don’t.Of course, some devices will be able to support the necessary hardware. Some laptop computers already have those MIMO antennas built in and can support three spatial streams. Most tablets could do that as well. But it’s going to be tough for smartphones to support the new standards. So the reality is the new bandwidth will free up capacity, which is good. But it will be awhile. And it will be a lot longer before you’re using your smartphone at gigabit speeds.
Second, those devices have to support gigabit WiFi, including the MIMO antenna systems and the greater data rates. There are WiFi adapters that will support two spatial streams, but that’s it. Because antenna design is limited by the laws of physics, the third antenna has to go somewhere, and it’s not clear where there’s space in a handheld device.