Gadgets Ndtv - Antennas are a key technology in a cellular phone system

Antennas are a key technology in a cellular phone system or any other wireless system. In a wireless system, an antenna converts guided radio wave energy (such as a signal traveling in a coaxial cable for television) to energy that is emitted or “radiated” out into free space. An antenna also does the reverse—it receives radio waves from the air and feeds them into the devices that detect, decode, and amplify them. In a cell phone system, there is one antenna in the handset and another in the base station tower. Both of these antennas transmit and receive waves. Base station antennas are the long, narrow rectangular devices, usually in groups of three, mounted high on a base station tower. The base station can be thought of as the “command center” that both sends and receives signals to the consumer’s hand set. The base station performs a “router” function to properly direct incoming and outgoing calls, and a “repeater” function to enable the consumer to communicate from cell to cell within the terrestrial cellular network. The base station antenna is mounted on tall towers because from this high point it is easier to stay in communication with cell phone users, who are often near the ground. For more info www.gadgets.ndtv.com