It’s clear that 5G cellular will be the choice for connecting to outdoor IoT sensors. Sensors for farm equipment in rural areas or for outdoor weather and traffic sensors in urban areas are going to most easily handled by 5G cellular since the technology will eventually be everywhere. 5G is particularly suited for serving IoT devices due to frequency slicing where just the right amount of bandwidth, large or small, can be allocated to each small outdoor sensor. 5G has another interesting feature that will allow it to poll sensors on a pre-set schedule rather than have the sensor constantly trying to constantly connect – which will reduce power consumption at the sensor.
It’s clear that the cellular carriers also have their eye on indoor IoT devices. It’s harder to say that 5G will win this battle because today almost all indoor devices are connected using WiFi.
There are a couple of different 5G applications that might work in the indoor environment. The cellular carriers are going to make a pitch to be the technology of choice to connect small inside devices. In my home I can get a good cellular signal everywhere except in the old underground basement. There is no question that cellular signal from outside the home could be used to connect to many of the smaller bandwidth applications within the home. I can’t see any technical reason that devices like my Amazon Echo or smart appliances couldn’t connect to 5G instead of WiFi.
But 5G cellular has a number of hurdles issues to overcome to break into this market. I’m always going to have a wired broadband connection to my home, and as long as that connection comes from somebody other than one of the big cellular carriers I’m not going to want to use 5G if that means paying for another monthly subscription to a cellular provider. I’d much rather have my inside devices connected to the current broadband connection. I also want all of my devices on the same network for easy management. I want to use one hub to control smart light switches or other devices and want everything on the same wireless network. That means I don’t want some devices on WiFi and others on cellular.
One of the sales pitches for 5G is that it will be able to easily accommodate large numbers of IoT connections. Looking into the future there might come a time when there are a hundred or more smart devices in the house. It’s not that hard to picture the Jetson’s house where window shades change automatically to collect or block sunlight, where music plays automatically when I enter a room, where my coffee is automatically ready for me when I get out of bed in the morning. These things can be done today with a lot of effort, but with enough smart devices in a home these functions will probably eventually become mainstream.
One of the limitations of WiFi today is that it degrades in a busy environment. A WiFi network pauses each time it gets a new request for a connection, which is the primary reason it’s so hard to keep a good connection in a busy hotel or convention center.
However, the next generation with WiFi 6 is already anticipating these needs in the home. WiFi can adopt the same frequency slicing used by 5G so that only a small portion of a channel can be used to connect to a given device. Events can be scheduled on WiFi so that the network only polls certain sensors only periodically. The WiFi network might only interact with the smart coffee pot or the smart window shades when something needs to be done, rather than maintaining a constantly open channel. It’s likely that the next iterations of WiFi will become nearly as good as 5G for these functions within a closed home environment.
There is an even better solution that is also being discussed. There’s no reason that indoor routers can’t be built that use both WiFi and 5G frequencies. While the cellular companies are gobbling up millimeter wave spectrum, as long as there is an unlicensed slice of spectrum set aside for public use it will be possible to deploy both WiFi on mid-range frequencies and 5G on millimeter wave frequencies at the same time. This would blend the benefits of both technologies. It might mean using WiFi to control the smart coffee pot and indoor 5G to connect to the smart TV.
Unfortunately for the cellular carriers, these duel-function routers won’t need them. The same companies that make WiFi routers today can make combination 5G / WiFi routers that work with the full range of unlicensed spectrum – meaning no revenue opportunity for the cellular carriers. When I look at all of the issues I have a hard time seeing 5G cellular becoming a preferred technology within the home.