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Fibre Optic Cable
                 A cable that communicates through electrical impulses is referred to as a fibre optic cable. These cables contain the
                 optical fibres that are plastic-coated and utilised to transmit data via light pulses. The plastic coating shields the optical
                 fibres from the effects of other types of wiring’s electromagnetic interference, heat, and cold. Compared to copper
                 wires, fibre optic cables offer faster data transmission. There is no electromagnetic interference that affects them.
                 However, fibre optic cable installation and upkeep are expensive and challenging.
                                           2 cm
                                                 High density polyethylene
                                                 insulation (17 mm)
                                                              Copper tubing (8.3 mm)
                                                                     Steel wires  Water-resistant jelly
                                            1 cm                                 casing 2.3 mm)


                                                                                      Optical
                                                                                      fibers


                        Do You Know?


                        •  Alexander Graham Bell is credited with creating Twisted Pair cables.
                        •  Coax is another name for coaxial cable.
                        •   In addition to being used for telecommunications, fibre optic wire is also employed by lasers, hydrophones
                         for seismic waves, SONAR, imaging devices, and sensors for measuring temperature and pressure.

                 Unguided Media

                 The electromagnetic waves are transmitted without the need of any physical medium in an unguided transmission. As
                 a result, it’s also called wireless transmission. Features of unguided media are as follows:

                 Ð ÐThe signal travels over empty space (air).
                 Ð ÐSignals can travel through sky propagation, ground propagation, or line-of-sight propagation
                 Ð ÐThe electromagnetic spectrum used for wireless communication ranges from 3 kHz to 900 THz.
                 There are mainly three types of unguided media which are as follows:
                 Radio Waves

                 Radio waves are electromagnetic impulses that can move in any direction through empty
                 space.  As  radio  waves  are  omnidirectional,  messages  can  travel  in  any  direction.  Due  to
                 the omnidirectional nature of radio waves, they can be interfered with if another receiving
                 antenna sends out a signal with the same frequency or bandwidth. The frequency range of
                 radio radiation is 3 kHz to 1 GHz. In case the transmitting and receiving antennas are not
                 aligned, so any receiving antenna can pick up the wave that the sending antenna sends.

                 Microwaves
                 The electromagnetic wave used in microwave communication has a frequency range of about (1–300GHz). With regard
                 to sight, electromagnetic waves only travel in one way, preventing any intrusion. Line of sight and communication
                 between the two endpoints are much simpler to create when the transmission medium is in alignment.
                 There are two types of microwave transmission which are as follow:

                 Ð ÐTerrestrial Type Microwave Transmission: Terrestrial Type Microwave Transmission with the propagation of the
                   microwave, which is primarily used for telecommunication over the air, both antennas are fixed for the signal
                   transfer on the transmitting and receiving sides.

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