In order to provide the greatest possible portability,
cell phones are generally very small, portable
telephones. A cellular telephone system is typically self-contained, receiving power from its own internal battery. The power provided by the battery is limited, particularly due to the need for a small battery in order to reduce the size and weight of the cell phone. Consequently, the telephones operate poorly in locations with poor base station coverage, such as sparsely populated areas. In
mobile communication systems, communication quality declines in areas where radio waves from the base station are weak. Furthermore, since radio waves from the base station do not reach the back of a mountain, there are areas where no services can be provided because of some particular geographical features. A RF booster is used to amplify and filter RF signals transferred back and forth between the portable telephone and an antenna, and improve usability in the available coverage of the cellular system of the portable telephone. The radiation power of the antenna in a portable telephone, may be increased using a booster before the antenna. The booster system receives a desired signal, then amplifies the received signal, and sends radio waves of high intensity toward an object area at the same frequency as that of the received signal. A typical booster for a cell phone may include a
power amplifier for amplifying the power of a transmission wave output from the phone to which the booster is connected.
