Fixed Wireless: The State of the Art
This is the second of a two-part post about wireless fixed wireless broadband. It focuses on current technologies and capabilities, while the first gave A Brief Recent History.
There is a famous saying that has long been applied to all things wireless: “Performance, reliability, cost, and distance – pick three.” The obvious point being that (like most things in life) you can’t have it all. But the fact of the matter is that, while there will always be some trade-offs, modern fixed wireless wireless systems are certainly pushing the envelope on all four. Let’s look a those four cornerstones, and throw in a couple more factors just for good measure.
Performance. It wasn’t long ago at all that a typical residential customer would be lucky to see 5-10 Mbps downstream and 0.5- 1 Mbps up on a fixed wireless link. Today, BeachiFi won’t even sell a link that can’t do at least 50-100 Mbps down and 10-25 Mbps up, and 90+ percent of our customer links will support 150+ Mbps.
Further, 25 GHz and millimeter wave (60+ GHz) devices are becoming routine. BeachiFi has a 25 GHz link that carries 1 Gbps full duplex (up and down simultaneously). For now,these are limited to point-to-point use and do not directly serve customer homes, but that will be changing soon. The bottom line is that the speed of fixed wireless is no longer a valid issue, especially when you consider the facts as presented in our post The Great Internet Speed Myth.
Reliability. One of the big problems with the early hardware was terrible reliability. The stuff had to work outdoors, in widely varying conditions, and it was once quite a problem – especially when some of it could be installed hundreds of feet up a tower, requiring specially trained crews to replace it. Well, that has really not been a problem for quite some time now.
We have been involved in projects from North Dakota to South Texas over the last ten years, and we rarely see equipment failures any more. Our sister company, PermiaNet, operates a large network in West Texas using the previous generation of the same equipment we are deploying in the Hill Country. Parts of that network have been fully functional – with the original gear – for more than seven years. During one stretch, we went 18 months with zero downtime, and the only maintenance was remote software upgrades.
Cost. Given both the performance and reliability already mentioned, these systems are surprisingly affordable. A typical radio installed on a customer’s home costs just over $100, and the routers and access points we include in every installation are about the same. This means that fixed wireless will generally cost only a fraction of competing technologies like fiber. And the cable companies are going the way of wireline phones (remember those?), with aging infrastructure that is increasingly expensive to maintan.
Distance. In any transmission medium, distance limitations are often simply a matter of the fundamental physics, and it’s no different with fixed wireless. However manufacturers are constantly getting closer to the theoretical limits, and using clever tricks to get surprising results. It used to be rare to consider anything beyond about a mile. We now routinely deploy point-to-point connections at 10 miles and beyond, and we have many customer links in excess of two miles, at speeds 10 times what we saw just a few years ago.
Interference is an ongoing challenge, especially as more and more providers try to co-locate on shared towers and compete for the same limited group of customers using the same radio frequencies. Overall, this degrades the performance for everyone, but newer hardware has gotten much better at isolating and filtering competing signals. Also, the higher-frequency products are opening up cleaner spectra and increasing speeds simultaneously.
Communities are becoming better educated and are taking control of what gets installed on their infrastructure. Water towers have long been an obvious home for fixed wireless deployments, but the entities who owned them would let anyone on for a fee. Now they are realizing that the only way to insure good service to their constituents is to limit installations and force tenants to cooperate on frequency allocation
This post has focused exclusively on unlicensed spectrum tech, because that is where virtually all of the commercially available and reasonably affordable solutions exist, and that will be true for a long time to come. Licensed spectrum products are being developed aggressively and deployed at the fringes, but we will expound on that another time.
