Deployment of fibre optics and the 5G network

With the involvement of technology in our lives, everything has become connected, our homes, our cars, our jobs and even medical assistance with operations being done remotely. With this kind of importance, we strive to improve the quality of networks and the speed of the internet; this is where the emergence of technologies such as fibre optics and the latest of all, 5G, comes in.

Our electronic devices communicate in a certain frequency band below 6 GHz, but this frequency band is very saturated. The more connected objects there are, the worse the service becomes and the longer the response time. Therefore, in order to achieve faster response times and process more data, it is necessary to work with millimetre waves, which have higher frequencies and a wider spectrum.

However, these waves cannot pass through buildings because they have a shorter range and can be absorbed by things like trees or rain. Therefore, it requires an array of small antennas. This network of many small, low-power antennas, connected either to a large antenna or via a fibre-optic loop, avoids obstacles and limits the potential harm of the waves. And here comes the massive MIMO (Multiple Input Multiple Output), this technology consists in multiplying the number of channels between the antenna and the connected objects. Future 5G antennas will be able to drive several hundred channels to connect thousands of sites. The multiplication of these signals in all directions can create interference that focusing will eliminate, this technology consists in focusing the waves with a fine and precise beam on each specific object.

At the same time, to save bandwidth and power, the frequency of each network is adapted to the needs of the applications thanks to algorithms that determine the best trajectory for each signal. Full duplex currently means that only one channel is used for communication between the antennas and the connected objects: the antenna can either transmit or receive. This limitation can now be circumvented with full duplex technology, electronic systems that can instantly reject the information passing through them.

Fibre optics on the other hand is a very high speed technology that allows you to connect to the Internet from your home or workplace. It is fairly recent (in commercial terms), but its experimental use dates back to the 1970s and its deployment is the subject of a vast project in France (the so-called THD plan). Indeed, equipping the territory with optical fibre has become a government priority in order to reduce the digital divide in France. The work should be completed by the end of 2022, and today more than 28.2 million homes are already eligible for fibre (and 32 million for all broadband technologies above 30 Mbps). More precisely, fibre is a glass wire that allows information to be transferred at the speed of light from point A (you) to point B (Internet servers).

Before fibre, ADSL technologies were applied to telecommunications and copper wires. This technology has three disadvantages: the volume is limited, there is a loss of signal depending on where you live, and when everyone is connected to the Internet at the same time, it creates a slowdown. With fibre optics, electricity is no longer transmitted over copper wire, but light is transmitted through glass. There is no signal loss, data rates are symmetrical and information travels at the speed of light (300,000 km/s).