Mobile phone repeater, extender, signal range extender (in building use only)
In April 2018, finally, OFCOM made a legal version of mobile phone range extenders, smart booster, repeater. Often termed bi-directional amplifiers or BDA’s.
This means that they are license free if they meet the strict limits of the document by OFCOM.
Strictly speaking, it’s much more complicated than all of those terms actually mean, but for the purposes of this article that’s pretty much what they do.
how exactly does this Mobile network extender, work in practice?
Basically, you have what’s called a donor antenna or donor aerial. This is an external aerial on your building where your phone signal for at least one if not all networks is poor or non-existent.
It is directional normally to improve signal strength and hopefully reduce the chances of picking up conflicting signals from other masts, as you might with an omnidirectional aerial.
This feeds to the Booster which relays this out of a second aerial port internally within the building.
This can, however, be split with up to 4 aerials maximum to cover larger or more complicated areas and buildings.
Because it is a mobile phone network extender, it works both ways, by transmitting and receiving on both ends of the unit some or all of the time.
Modern buildings are actually very good at stopping any sort of radio signals entering or leaving a building.
Which is why you often get a signal outside, but a poor signal inside if at all.
This is because of insulation and materials used in construction. Foil lined insulation panels in false walls and for insulation on exterior walls, plus metal film on windows to reflect heat in or out of windows.
Power limits are strict and pretty low, but any signal is better than none, plus mobile phones are all digital now, so once you get a good enough stable signal, you will not notice how strong or weak it is. It will just work.
A few things to mention here are that you can only use one network on any signal unit.
This means if you want to have all four UK networks, (EE, Vodaphone, Three and O2) you will need 4 units or systems to do this.
Often company phones are all on one network, at home your family may be too. So this then becomes less of a problem.
One such unit is the Cel-fi GO X
or it’s bigger brother the Quatra system