Hello, everyone!
Today, I would like to share with you an article about remote communication systems - analog.
The classification of telecommunication systems depends largely on the characteristics of the information transmitted, the nature of the channel used for transmission, and the method of embedding.
Analog systems:
In these systems, the signal representing information is transmitted simultaneously and continuously over time. When modulation is used at the transmit end, one of the carrier factors is changed in proportion to the transmitted signal.
The carrier is usually sinusoidal and has a frequency much greater than the frequency of any of the signal components to be transmitted. This type of modulation is called continuous wave modulation. It is clear that this type of embedding is appropriate for signals that constantly change with time.
If the factor that is changed in the modulation process is the amplitude of the carrier, then the modulation is called amplitude modulation.
If the factor is frequency, then the modulation is called frequency modulation.
If the factor is the phase of the carrier wave, then the modulation is called phase modulation.
Amplitude modulation is used mainly in radio and television broadcasting systems, in single side band communication systems over long distances, and in frequency division multiplex (FDM) table-forming circuits, to obtain a single signal representing a large number of independent signals expressing different information (telephone channels, television channels). This is done by shifting the basic frequency packet, so that each signal occupies a new space, and then it is stacked one after the other.
Frequency modulation is used in high-quality broadcasting systems and in terrestrial and satellite microwave communication systems.
As for phase modulation, it is rarely used in analog systems, while it is used more often in digital systems in the form of phase shift keying (PSK). The importance of phase modulation lies in the close relationship between it and frequency modulation, so they can be classified as angle modulation.
Also included in this classification are telecommunication systems in the base band that transmit the signal directly on the various wired transmission lines, and this signal can be single (telephone signal, picture signal...) or it may be a table-based frequency division (FDM) signal.
You are welcome to like and exchange in the comment area. Stay safe and Thank you!
