I took this piece of text from http://www.fiercebroadbandwireless.com to develop this post.
The Femto Forum and other industry experts have pointed out that LTE is approaching the theoretical maximum information transfer rate (otherwise known as Shannon’s Law) and further improvements will only be possible by rolling out smaller cells. The higher data speeds might not be achieved with LTE femtocells because the wired network inside the home that will backhaul the wireless traffic won’t have enough throughput to handle the higher data speeds LTE provides.
So… in the future, if we want to deploy 5G and beyond, we will need to reduce the cell size.
I have been writing a few articles about this, together with the University of Essex, that were published in scientific conferences, talking about future wireless services offering Gigabit capacity using UltraWide Band technologies (UWB), but this is not a research blog so I will skip this.
In any case, what I want to point out is that wireless is, and always will be the limiting media. Actually, it is very easy to calculate the bandwidth that you can have in a CELL. Basic maths: one multiplies the available spectrum of the channel (several MHz) by the modulation efficiency (bits/Hz) and then you have the data rate that can be delivered using a specific frequency plan and modulation format. You may end up with datarates in the rates of hundreds of Mbps but this bandwidth is shared among all the users of the channel.
Talking into account that the wireless medium is inherently shared, performance can easily decrease with more than one user shared the channel.
To have more capacity, you can increase bandwidth by going up in the spectrum and using higher frequencies but then you have propagation issues…
This means that the ONLY way to deliver future very high speed services is to reduce the size of the cells so less users are connected to the cell and to increase the frequency carrier to have more spectrum available, having then propagation issues.
So… what can we do to find an effective solution? For me the only way is to mix optics and wireless, so fiber reaches the remote antennas and then, those distribute high datarate mobile services.
However, this means that the deployment of future mobile services will require more investments in outside plant because much more antenna stations will be required.
As I am proclaiming in my last posts, we need fiber, we need fiber for fixed access and we will need fiber for future wireless services so…
We should consider integrating everything together, save costs and develop the country in an efficient way.