Different Types of Antennasby Rebekah Worsham
Antennas, electrical devices that work by transmitting or receiving electromagnetic waves, are necessary for the proper transmission of television programming, satellite broadcasts, radio broadcasting and for the use of cellular telephone communications. Antennas come in a variety of shapes and sizes and are often determined based upon the purposes for which the antenna is used.
Television antennas send and receive signals for the purpose of broadcasting television, both traditionally and through satellite. Despite common misconceptions, there is no difference between antennas used for digital television or high definition television as both work based on the same concept of signal reception. Television signals come in a variety of shapes and sizes including Dipoles, Reflector, Log-Periodic Dipole Arrays and the Yagi antenna. While all of these models work by intercepting or receiving broadcasting signals and converting these signals into the proper format for viewing, the primary difference between these varieties is the size, signal strength and shape, which is pre-determined by the manufacturer.
Radio antennas work under the same basic concept as the television antenna, receiving broadcast signals and converting them into the proper format for listening. The obvious difference between the two is the fact that television antennas also convert the signals they receive into picture display, while this is not required with radio. Radio antennas, much like television antennas, come in a variety of shapes and sizes based upon the need of the consumer. Smaller antennas such as those that are designed to be used on a portable radio or iPod range between small and microscopic in size, while antennas that are necessary for the reception of radio by car are typically thin by design, but much longer in size.
Cell Phone Antennas
Antennas included with personal cell phones are very thin and lightweight and no more than a couple of inches in height. In addition, some newer cell phone models do not contain traditional-looking antennas, instead utilizing microscopic antennas that are embedded within the phone itself. Cell phone antennas are used to allow the user to intercept signals sent out by cell phone towers, thus presenting better call quality and fewer dropped calls. The signal received varies greatly based upon provider and the location and strength of the tower from which the cell phone is receiving its signal. Even the best of antennas are only as good as the strength of the signal its cell phone tower provides.
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