'Modem' is the abbreviation of modulation and demodulation. The importance of modulation and demodulation in a communication system has already been discussed. We usually use a modem when we need to connect our laptops to cellular networks. If you think this is the only modem application, you are wrong. Almost all devices require a modem or router to connect to the internet. Even your cell phone contains a modem. We usually use a telecommunication line, cable, or fiber optics to connect one cell tower to another. Copper wires were commonly used in the past. Fiber optics has since taken its place. The only wireless connection is between your device and the cell tower.
Now we'll talk about what modems do. As we know, communication mediums like — wireless channels, cables, telecommunication lines, fiber optics, etc. - are all analog in nature. Digital data cannot be sent directly to analog mediums. We convert digital data / quantized digital into analog waveforms via modulation to change any of the three properties: amplitude, frequency, or phase. We already discussed modulation strategies multiplex data in the modulation chapter. As a result, we can obtain faster data communication.
Only zeros and ones are understood by computers. Through the optical wire, we transfer many zeros or one. To represent zeros and ones, we adjust the energy level, frequency, and phase of the signal in such cables or fibers (especially for ASK, FSK, and PSK). We demodulate the incoming signal and get the zeros and ones at the receiver device. In this instance, demodulation is required.
So, for example, if you wish to connect your laptop to a cellular network, you can do so by plugging in a USB modem. It modulates digitalized computer data, which consists of zeros and ones. The analog modulated data is transmitted to the cell tower via a wireless channel via your modem's antenna. If your laptop receives any data in response, the modem will demodulate the data to zeros and ones.
Your smartphone also employs a modem, a 'connectivity module' inside your microchip.
#data transmission NIC hub modem
Explain different types of cables used in networking along with the coding and connecting style.
