What is 5G ?

Everyone  likes a fast internet. Imagine downloading an 8 gigabyte file in  4 seconds. We have probably heard about the 5G prophecy... how 5G will rule the internet with blazing speed.

Well, what is 5G ?
5G is a buzzword, there is no standard technical definition for 5G but it is okay to think of it as the 5th generation of improvement to cellular networks. It is known that 5G will bring network speeds faster than 4G. These network speed will support new technologies like virtual reality, internet of things, autonomous vehicle, remote health monitoring and many more operations seamlessly.

To achieve these gain in speed for 5G, engineers and researchers are making changes (improvements) in the these areas

Millimeter Waves: As of today (12/02/2018), most network operations are carried out at frequencies below 6 GHz. Our popular WiFi for example operates at mostly 2.4GHz or 5GHz. As the number of internet or network capable devices grows, the existing frequency spectrum used for network operations gets used up. Hence, there is need to expand this spectrum. Researchers are now looking at the possibility of transmitting at higher frequencies (millimeter waves) - from 30GHz to about 300GHz since this will mean more bandwidth to accommodate the increasing number of  network devices. However, there is a draw back. Millimeter waves travel at line of sight and as such, they suffer signal degradation / loss due to obstacles (like trees, humans, buildings, rain) that often interfere with the signal's along its path. To tackle some of these problems, researchers are looking at Small Cell.

Small cell: In 5G, industries and academia are opting to deploy several small and lower power base station that could also act as signal repeaters or relays. The idea is that, with several small cells deployed, beams would not need to travel far and the effect of obstacles would be reduced. Another advantage of using small cells is they can be deployed in a way that they will provide better signal coverage to areas that were not previously covered.


Massive MIMO  (Multiple input multiple output) - 4G networks use up to a dozen antenna for handling all network traffic at a base station. In 5G, up to 64 or  more antennas will be used to handle network traffic. Supporting up to 64 antennas will mean more network capacity to handle more traffic however, this comes with its problem - interference, Signals can easily interfere with one another. To counter interference, one of the solution 5G proposes is to direct signals towards specific targets as opposed to broadcasting signals without directions. This act of directing signal motivates the use of beamforming in 5G.

Beamforming: To mitigate the effect of interference, improve network capacity and provide better coverage, signals can be directed or beamed to a specific user or to a group of users.

Full duplex: In order to maximize throughput, it makes sense that uploading and downloading of data should happen at the same time. 5G aims to use a full duplex mode in order to be able to transmit and receive at the same time. Full duplex implies the uploads and downloads happen at the same time.

Virtualization: Researchers are looking at how to remove algorithms and programs that power the network, away from fixed big and heavy network boxes. These algorithms and programs formally embedded in the hardware boxes will run as software on high end computer processors on the "cloud". Why virtualization ? By running some of these programs in the cloud, It will be easy to manage the network from one central source as opposed to having several big boxes. Changes - both software and hardware upgrades could be done easily. The network will be more flexible. Virtualization also comes with its challenges. Since programs will run in the cloud, they will need to communicate with the radio units and boxes in the field. This could introduce security concerns.
Virtualization can introduce latency - the time it takes to communicate between the radio units and the algorithms in the cloud.

Hardware: Think about this, when your computer gets slow, you could upgrade the processor, or the memory or buy a new one with better specs. Likewise in 5G. New set of hardware - higher end processors, memory, antennas, radios, chips and algorithms with better efficiency. This does not eliminate all the latency that result from removing algorithms from the radio boxes in the field, but it does help improve the overall latency.

(Edit: 10/18/2019)