Chapter IV: Amplitude Mod.
Lecture 7
© Dr. Wajih Abu-Al-Saud
Baseband vs. Passband confabulation Systems
Communication system of ruless can be classified into two groups depending on the prescribe of frequencies they use to transmit information. These communication systems are classified into BASEBAND or PASSBAND system. Baseband transmission system sends the information bless as it is without modulation (without oftenness shifting) while passband transmission shifts the signal to be familial in oftenness to a higher frequency and then transmits it, where at the receiver the signal is shifted back to its original frequency. Almost tout ensemble sources of information generate baseband signals. Baseband signals are those that have frequencies relatively plastered to zero such as the human voice (20 Hz 5 kHz) and the characterisation signal from a TV tv camera (0 Hz 5.5 MHz). A plot of an audio signal and its frequency spectrum are shown below, where it is seen that the most of the power of the audio signal is tough in the frequency range from (0 4 kHz). The earphone system used for homes and offices, for example, may transmit the baseband audio signal as it is when the call is local (from your home to your neighbors home).
However, when the telephone call is a longdistance call that is transmitted via microwave or satellite links, the baseband audio signal becomes contradictory for transmission and the communication system becomes a passband system. Similarly, transmitting the video signal from your camera to your TV using a fit out represents a baseband communication while transmitting that video signal via satellites passband transmission. Therefore, baseband transmission, which is easier than passband transmission, is usually used when communicating oer wires, while overtheair transmission requires passband transmission. Notice that even over wires, the transmission may be passband transmission in specific applications.
(a) (b) An audio signal in (a) timedomain,...If you want to get a full essay, order it on our website: Ordercustompaper.com
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