Wireless communicaiton is used to meet many needs. it has four Modes Radio , Free- space optical , sonic, Electromagnetic induction. Perhaps The most common wireless technologies use radio. With radio waves distances can be short, such as a few meters for television or as far as thousands or even millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mice, keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones. Radio communication, microwave communication, for example long-range line-of-sight via highly directional antennas, or short-range communication. Base stations - BS - may be stand alone transmission systems that are part of a cell site and are composed of an antenna system (typically a radio tower), building, and base station radio equipment. Base station radio equipment consists of RF equipment (transceivers and antenna interface equipment), controllers, and power supplies.