To accomplish this, the antenna systems would have to use a distributed MIMO (multiple input multiple output) antenna arrays, and a sophisticated control system to keep signals reaching users as they move around.
Verizon’s fixed wireless approach eliminates the problems with signal blockage and reflections, but it’s not a mobile 5G solution. AT&T’s 5G evolution isn’t using millimeter waves yet, although the company has recently acquired Straight Path Communications, which holds a large collection millimeter wave licenses.
The millimeter wave plans also face another problem that has nothing to do with technology, which is public resistance to cell sites. While the high frequencies used will eliminate some issues such as large unsightly antennas, the resistance to cell sites has been drifting to a concern about radiation exposure. A major impediment to establishing cell sites is a pervasive (and largely unfounded) fear that the radio waves they transmit are somehow harmful.
The fact that today’s cell site transmitters typically put out less power than a standard light bulb is irrelevant to the people fighting them and because millimeter wave service will require hundreds to thousands more sites, you can expect the opposition to grow accordingly. T-Mobile will avoid all of those problems by using a much lower frequency and because it can simply add the new capability to its existing cell sites.
What all of this means is that 5G service is a ways off for most people, despite the hype in press releases. T-Mobile probably has the best outlook for implementing 5G mobile service because the company can avoid many of the engineering challenges that accompany millimeter wave use.
Verizon will almost certainly have at least some 5G service up and running in 2017, but you won’t be able to use it on your cell phone as you travel around. AT&T’s approach to 5G really isn’t what you’d expect 5G to be, because it’s essentially enhanced LTE.
You’ll notice that I haven’t mentioned the number four carrier, Sprint, in this discussion. The reason is that this carrier is focusing on getting its LTE network into competitive shape. While the company is deploying small cells in Manhattan and starting to deploy advanced LTE, actual 5G deployment is still in the planning stages.
One reason for all the talk about 5G right now that there are a lot of engineering challenges still to be overcome. But a second, and more important, reason is that the 5G standards are still being written. A draft standard should be available in a year or so, but the final standard is also a way off.
For now, you’ll hear a lot of hype about 5G, but not much actual progress. This is a case where progress is hard and complex. It will all take longer that anyone wants to admit to deliver real 5G mobile service.