Never get a strong enough signal with your cell phone? No Problem!!
Simply buy a 100,000 yotta-watt (10^30 watt) magnetron and design a focusing reflector to focus all the microwave energy into a super-tight spot so you can aim it at the cell-phone tower.
It will definitely make sure your signal is strong enough, although it may blow up the cell phone tower. That's the phone company's problem for not making towers able to handle 100,000 yotto-watts of microwave energy concentrated into a 1mm beam. They really should work on that.
You can also have upgrades done and get multiple novemtriginnovemtriginnovemtrigintillion (10^1,728,000) watt magnetrons and focus all the energy into one novemtriginnovemtriginnovemtriginnovemtrigintillionth of a millimeter. Be careful though. You will create an atomic explosion by touching any matter with it..