Poor mobile phone signals are a very common problem, A common situation is a home or office with a little or no signal bar, frequently dropped the calls. Whether or not a repeater can help with the situation but it depends the cause of the problem. Bad cellphone connection is always been the problem all over the world, and the reason for bad signal falls under this two things: localized poor coverage due to high infrastructures and destructive interference and lastly is the obstacles between your phone and the tower.
Lets say for example you live in the middle of the desert and the towns and major roads are miles away from your distance. If you are very far from the nearest cell site tower and have to drive two miles from your location, it will not be easy for the for a repeater to help you get a signal. because it cannot create a signal where it has no signal already.
The same as you are living at the mountainside a repeater cannot pick up a strong signal because of that obstacles to improve your coverage and autocad. Geographically, reception barriers are often insurmountable, The cause of your mobile phones bad signal is just the same as having a construction materials used in your home or office or the buildings around you.Cellular signals cannot easily pass through a concrete materials, That is why you may gain up to two or three bars by hanging out of upstairs window. it is the blocking effect of the building walls.
Thanks to our business partner Angela I. Valero that give this useful information to us!