In just a few years we have gone from having to disconnect the landline to connect to the Internet to have a connection of up to 1 Gbps on our mobile phones. The world is moving fast, and as more people progress they have access to the 4G network, which is beginning to become saturated because there are too many devices connected. That implies slower speeds, interference, etc. The solution? Make the leap to 5G.
We have been talking about 5G for a long time as the connection of the future, which will revolutionize connected devices, the Internet of Things, autonomous cars … But what exactly is 5G? How does this not-so-new technology work? Well, that is precisely what you will discover in this article.
As you know, each new generation of networks means an improvement in speed and functions. If the 1G network allowed us to make calls, the 2G let us send SMS and the 4G allowed us to watch video on demand in streaming. The 5G network will be able to host up to a thousand times more devices than there are today and will be up to 10 times faster (that is, we can download videos in FullHD in a matter of a few seconds).
What exactly is the 5G network?
The real answer is that it is still not well known since experts have not been able to offer a definition. What is clear is that, roughly, it is a commercial way of calling a new wave spectrum that would allow the current 4G network to be released and accommodate more devices. Although the 4G network reaches the GB transmission speed, users cannot take advantage of it due to obstacles such as trees, buildings, etc. The 5G would come to solve this problem.
This new network would increase its speed to 10 Gbps, speed more than enough for Smart Cities, autonomous cars and the Internet of Things to be implemented in a productive way. More or less, this would be a summary explanation of what 5G is, but what you should know is that behind this new connection there are five technologies that must go hand in hand.
The technologies needed for 5G
High-Frequency Millimeter Waves
Each of the devices that you have connected to the network are using a very specific frequency of the entire radio wave spectrum. Specifically, the 4G network is below 6 GHz. This would not be a problem if there were more and more and more gadgets connected. It is like a road with a few lanes and more and more cars. They will be passing all but little by little, generating a bottleneck.
With this first technology, what is wanted is to use higher frequency spectra, increasing the range to 300 GHz (a strip that has never been used for mobile networks). It is as if to that road from before you add 10 more lanes. Cars will move smoothly again and traffic jams will be eliminated, that is, by having more spectrum available, more devices can connect to the network without saturation and there will be more bandwidth for everyone.
However, when using more frequent waves we find a problem, and these are very difficult to pass through obstacles such as buildings and tend to be absorbed by trees and rain. To solve this problem, the second technology must be used.
As you know, throughout the city there are different telephone antennas to which your phone connects as you move through it. However, imagine that there was only one antenna in the center of your city and that you live as far away from it as possible behind a block of flats. Since the 5G network has problems to overcome these types of obstacles, it is possible that your home may not receive a signal.
This requires these intelligent antennas, which are nothing more than repeaters. These repeaters, smaller than normal telephone antennas, can (and should) be placed across a city to bounce the signal and reach the sites that otherwise would not reach, thus solving the problem we mentioned before.
MIMO stands for Multiple Inputs Multiple Outputs. The 4G antennas to which we all connect every day have a dozen small ports that are responsible for managing the connection of all mobile traffic. The new Massive MIMO antennas can have hundreds of these ports, allowing up to 22 times more mobile connections to be managed.
Of course, these antennas have their own complications. The current antennas emit the signal in all directions, and if such interference is already generated, imagine how it will be when where there were twelve ports before there are now one hundred. The interference would be huge and the network would be almost unusable. That is where the fourth technology comes into play.
Beam shaping or beamforming
The beamforming is like a traffic light for mobile networks. Instead of the antennas emitting in all directions at once, this technology allows them to emit to specific users, that is, directly to your mobile. This would prevent interference and is much more efficient than a single antenna managing all connections, and would also allow a single antenna to manage many more data inputs and outputs.
Its operation is complex but very curious. Imagine you go down the street and want to make a call. Your signal bounces around the buildings and objects around you and is received by a Massive MIMO antenna, which records the time it has taken to arrive and the direction from which it comes. Then use an algorithm to triangulate the place of origin of this signal and send the data following the most optimal route.
The most interesting thing is that, in order to avoid interference, the antennas, using beamforming, can bounce the data packets in buildings and objects in such a way that they never interfere until they reach the recipient. Imagine a pool table where all the balls are moving at the same time but without touching each other until they reach the hole. This brings us to technology number five.
To understand this we will use the calls as an example. When you call on the phone or talk or listen, but you can’t do both at the same time. If you are talking to me and I interrupt you, the antenna cuts you off so I can talk, and vice versa, because the antenna can either send or receive data, but not both at the same time, like the old walkie-talkies, basically.
This is due to the principle of reciprocity, which is the tendency of radio waves to travel back and forth on the same frequency. Imagine a train that goes on some tracks. The tracks can lead to a one-way train, but they cannot take a train back along the same rail, because then they would collide. Trains are data sent and received, and the crash would be interference. What was done so far? Take turns If there was an incoming signal, the outgoing one would “move aside” until the first one passed, and then sent.
The solution? That the incoming data go on the one hand, and the outgoing on the other, right? Full Duplex goes further, since using silicon transistors high-speed alternators can be made that can momentarily reorient a signal. It’s as if you have a train track but you have it split in two and then come back together. You would make a one-way lane through which two trains could pass without crashing.
All this is pure and hard theory and these five technologies are still working to be as efficient as possible. For now we have to wait, although it is clear that soon we will have more speed, more efficiency and more possibilities to make this world a more connected world.