I live in Asheville, NC and our town is hilly and has a lot of trees. Trees are a major fixture in lots of towns in America, and people plant shade trees along streets and in yards even in states where there are not many trees outside of towns.
5G is being touted as a fiber replacement, capable of delivering speeds up to a gigabit to homes and businesses. This kind of 5G (which is different than 5G cellular) is going to use the millimeter wave spectrum bands. There are a few characteristics of that spectrum that defines how a 5G network must be deployed. This spectrum has extremely short wavelengths, and that means two things. First, the signal isn’t going to travel very far before the signal dissipates and grows too weak to deliver fast data. Second, these short wavelengths don’t penetrate anything. They won’t go through leaves, walls, or even through a person walking past the transmitter – so these frequencies require a true unimpeded line-of-sight connection.
These requirements are going to be problematic on the typical residential street. Go outside your own house and see if there is a perfect line-of-sight from any one pole to your home as well as to three or four of your neighbors. The required unimpeded path means there can be no tree, shrub or other impediment between the transmitter on a pole and each home getting this service. This may not be an issue in places with few trees like Phoenix, but it sure doesn’t look very feasible on my street. On my street the only way to make this work would be by imposing a severe tree trimming regime – something that I know most people in Asheville would resist. I would never buy this service if it meant butchering my old ornamental crepe myrtle. And tree trimming must then be maintained into the future to keep new growth from blocking signal paths.
Even where this can work, this is going to mean putting up some kind of small dish on each customer location in a place that has line-of-sight to the pole transmitter. This dish can’t go just anywhere on a house in the way that satellite TV dishes can often be put in places that aren’t very noticeable. While these dishes will be small, they must go where the transmitter can always see them. That’s going to create all sorts of problems if this is not the place in the home where the existing wiring comes into the home. In my home the wiring comes into the basement in the back of the house while the best line-of-sight options are in the front – and that is going to mean some costly new wiring by an ISP, which might negate the cost advantage of the 5G.
The next consideration is back-haul – how to get the broadband signals into and out of the neighborhood. Ideally this would be done with fiber. But I can’t see somebody spending the money to string fiber in a town like Asheville, or in most residential neighborhoods just to support wireless. The high cost of stringing fiber is the primary impediment today for getting a newer network into cities.
One of the primary alternatives to stringing fiber is to feed neighborhood 5G nodes with point-to-point microwave radio shots. In a neighborhood like mine these won’t be any more practical that the 5G signal paths. The solution I see being used for this kind of back-haul is to erect tall poles of 100’ to 120’ to provide a signal path over the tops of trees. I don’t think many neighborhoods are going to want to see a network of tall poles built around them. And tall poles still suffer the same line-of-sight issues. They still have to somehow beam the signal down to the 5G transmitters – and that means a lot more tree trimming.
All of this sounds dreadful enough, but to top it off the network I’ve described would be needed for a single wireless provider. If more than one company wants to provide wireless broadband then the number of devices multiply accordingly. The whole promise of 5G is that it will allow for multiple new competitors, and that implies a town filled with multiple wireless devices on poles.
And with all of these physical deployment issues there is still the cost issue. I haven’t seen any numbers for the cost of the needed neighborhood transmitters that makes a compelling business case for 5G.
I’m the first one to say that I’ll never declare that something can’t work because over time engineers might find solutions for some of these issues. But where the technology sits today this technology is not going to work on the typical residential street that is full of shade trees and relatively short poles. And that means that much of the talk about gigabit 5G is hype – nobody is going to be building a 5G network in my neighborhood, for the same sorts of reasons they aren’t building fiber here.