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The New Way of Transmission: Broadband
Quicker than Telephone Line Transmission
In general electronics and telecommunications, any signal or circuit which consists of or handles a broad range of frequencies is known as broadband. This is a term that is used relatively and is best understood in the context of wide frequencies.
The broadband range of signals is broad as the term itself implies, and is different to radio signals which carry a very narrowband consisting of Morse code. Broadband can carry much more than just Morse code and includes speech and music and at the same time does not lose the high audio frequencies required to reproduce realistic sounds.
While the ordinary television antenna called “normal” can receive a certain range of channels, “broadband” television antennas can receive a much higher number of channels. While for data communication the device known as a modem can transmit in a bandwidth of 64K bits per second over telephone lines, the broadband equivalent known as ADSL can, over the same telephone line, carry a bandwidth of several megabits per second.
In modern terminology, broadband with regard to data communication may also refer to data transmission over fiber optic cables as opposed to the 600 bits per second achieved by using a telephone modem. There are however other more technical interpretations of the term broadband and they mainly refer to the simultaneous transmission of data consisting of multiple pieces of data in order to increase the effective rate of transmission without taking into consideration, the actual data rate of transfer.
Another use of broadband is through multiplexing, which means sending data over separate physical channels simultaneously and allows for multiple accesses. These channels may be separated from each other by time (time division multiplexing) or in carrier frequency or wavelength division multiplexing and finally, in access method. Taken as a whole, they constitute broadband communication while separately they are considered as narrowband.
Due to the fact that a wide band of frequencies are used, information may be multiplexed by sending them on many separate channels or frequencies within the band at the same time thus enabling it to transmit more data in a specified time frame just like the greater number of lanes on a highway allow more number of cars to travel at the same time.
There are also certain minimum data transfer rates that are said to define when the data is being transmitted as broadband and when it is narrowband. This minimum rate of transfer for broadband transmission may vary between at least 20KHZ to 256KBPS to channels that are at least 6MHZ wide.
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