An I.C.E. System is a device used to boost the cell phone reception to a local area by the usage of an exterior donor antenna, a signal amplifier, and an internal rebroadcast antenna. These are similar to the cellular broadcast towers used by the network providers, but are much smaller. Modern repeaters and cellular amplifiers work by rebroadcasting cellular signals inside the building. Berk-Tel Communications, Inc. provides I.C.E. repeater systems that are suitable for commercial buildings as well as large homes.