A Mobile Phone Repeater, in the mobile phone industry, is a device used for boosting the mobile phone reception to the local area by the usage of a reception antenna, a signal amplifier, and an internal rebroadcast antenna.
These are similar to the cellular broadcast towers used for broadcasting by the network providers, but are much smaller, usually intended for use in one building. Modern mobile device repeater amplifiers can rebroadcast mobile signals inside a building. The systems usually use an external, directional antenna to collect the best mobile signal, which is then transmitted to an amplifier unit and retransmitted locally, providing significantly improved signal strength.
The more advanced models allow multiple mobile phones to use the same repeater at the same time, so are suitable for commercial as well as home use.