5G certainly represents one of the hottest topics in the world of technologies. Not only does it substantially improve the performance of previous generation networks such as 4G, but it differs from it for a reason clearly linked to the connection method. In the case of 5G, there are two ways to connect: on the one hand, on the Sub-6 GHz frequencies, on the other hand, on the so-called millimeter waves (mmWave) above 24 GHz.

The analysis of Digital Trends shows that when your smartphone connects to 5G, you could actually connect to both of these two types of 5G network coverage.

But depending on whether you connect to sub-6 GHz or mmWave 5G frequencies there are - big differences in terms of performance.

What is 5G sub-6Ghz?

The differences between the Sub-6 and mmWave millimeter waves are quite simple: The Sub-6 5G uses frequencies that are below 6 GHz, the same where 4G, 3G, and 2G networks have historically always worked. It is presumably p in this portion of the spectrum that the first steps of 5G will also take place in the coming years.

In the US, but also in various European states, operators are therefore building "national" 5G networks quickly, using the existing towers and spectrum, because Sub-6 5G requires nothing more to function than an upgrade of the towers.

So, just make a few 5G-specific changes to the towers so that they start providing 5G service alongside 4G across the country.

And since carriers already hold large amounts of spectrum on these lower frequencies, they can deliver relatively high throughput with 5G without compromising their 4G offering.

This means that in the next few years most of the time you are using 5G you will be on Sub-6 frequencies. And in fact, at least for the first few years, the performance of 5G will not be too much better than that of the 4G you are used to.
T-Mobile

Sub-6 Ghz 5G networks are not too different from 4G

The problem is that Sub-6 networks don't offer dramatically better performance than more modern 4G networks.

And it could not be otherwise, given that if it is true that it is 5G, it is also true that this 5G works in several respects with all the restrictions of 4G networks since it uses contiguous frequency bands.

5G sub-6 networks are only marginally faster, with slightly lower latency, than 4G networks.

The only substantial improvement in the experience that can be found with the Sub-6 is in the so-called "midband", between 2GHz and 6GHz, where 4G networks traditionally do not work as opposed to 5G.

With a large amount of unused spectrum, no competition from existing 4G networks and some new networking technologies, midband 5G can be a great network that balances faster speeds with good range and object elimination. Medium bandwidth will be an important part of any operator's overall 5G strategy.
What is 5G mmWave?

Then there is the mmWave (millimeter wave), which uses significantly higher frequencies, ranging from 30 GHz to 300 GHz. Operators in the US currently operate between 30 GHz and 40 GHz, but government auctions have recently released new spectrum up to at 48 GHz. Beyond that, the 60GHz range is actually an unregulated spectrum and 70GHz-plus is often used for very specific point-to-point fixed wireless networks.

But back to 5G mmWave on your phone: it is a completely new network that has no relation to existing 4G networks or infrastructures. This means it has incredible potential, but will take much longer to deploy than Sub-6 networks.

Utilizing a previously intact portion of the spectrum, mmWave 5G networks can deliver ultra-high data rates and extremely low latency. Whenever you hear about 3 Gbps download speeds, 1 millisecond latency, and futuristic real-time communications between devices, cars and medical equipment, it's all based on mmWave (millimeter waves).
Small cells

Verizon, AT&T, and T-Mobile have all launched mmWave networks, but distribution is slow. Because the mmWave frequencies are so high, significant coverage issues arise. The higher the frequency, the shorter the radio waves can travel. This means that there will be a need for many towers. But calling them "towers" is a misnomer: unlike traditional cell towers, these are the so-called "small cells" which are hyperlocalized to provide services to an area as small as a city street, at least in one direction.

5G spectrum

All this is necessary because of the short range of millimeter waves (mmWave) and also because obstacles of any kind can greatly affect its performance. Buildings, cars, trees, and even windows can interrupt an mmWave signal. So now, in order to provide something that comes close to coverage, you need to have hundreds and thousands of small cell sites (small cells) of mmWave cells littered along the roads. In short, with the mmWave there is no escape. Coverage must be widespread.

With these technical hurdles, mmWave millimeter-wave networks rollouts are very slow. Although you can find mmWave 5G in parts of some cities, for the moment, at least in the US, these are not stable connections: the direction you are facing can also determine if you are receiving a signal. But when you get a signal, the speeds are absolutely mind-boggling: download speeds of over 3 Gbps, with latency in the order of a few milliseconds. And the mmWave also has very large capacity, which means that multiple devices can be connected to a single network at the same time, without any service degradation. This is certainly an absolutely revolutionary aspect.
Soon it will be possible to use both the Sub-6 and the mmWave.