Telecommunication is the transmission of signals over a distance for the purpose of communication. In earlier times, this may have involved the use of smoke signals, drums, semaphore, flags or heliography. In modern times, telecommunication typically involves the use of electronic devices such as telephones, television, radio or computers. Early inventors in the field of telecommunication include Alexander Graham Bell, Guglielmo and John Logie Baird.
A telecommunications network is any arrangement where a sender transmits a message, to a receiver, over a channel, consisting of some sort of medium.
Basically, Wire and cable of the telecommunication segments covers a variety of end applications ranging from single telephone cables to LAN and high frequency radio cables. There are 3 types of wired technology media:
Fiber optic:
Fiber optic is a glass or plastic fiber that carries light along its length. Fiber optics is the overlap of applied science and engineering concerned with the design and application of optical fibers.
Advantage:
· uses pulses of laser-generated light
· faster transmission speeds
· freedom from electrical interference
· less susceptible to interference (noise) and, therefore,more secure
· smaller size (thinner and lighter)
Coaxial cable
Coaxial cable is an electrical cable with an inner conductor surrounded by a tubular insulating layer typically of a flexible material with a high dielectric constant, all of which are surrounded by a conductive layer called the shield (typically of fine woven wire for flexibility, or of a thin metallic foil), and finally covered with a thin insulating layer on the outside. The term coaxial comes from the inner conductor and the outer shield sharing the same geometric axis.
Twisted-Pair Wire
Twisted pair cabling is a type of wiring in which
two conductors (the forward and return conductors of a single circuit) are twisted together for the purposes of canceling out electromagnetic interference (EMI) from external sources. It is ordinary telephone wire.
Wireless technology
This technology use to solve when inconvenient, impractical or impossible to install cable. It is a technology in which radio signal send through the air.
There are many type of wireless technology which are:
Wireless LANS
Usually provides a connection through an access point to the wider internet. This gives users the mobility to move around within a local coverage area and still be connected to the network.
Uses wireless radio-wave technology to connect PCs within an office or a building.
WiMAX
Newest of the network types. The technology is based on the IEEE 802.16 standard (also called Broadband Wireless Access)
Similar to Wi-Fi, but operates over longer distances and at higher speeds. The technology provides up to 10 Mbps broadband speed without the need for cables.
Can use both licensed and non-licensed frequencies
Bluetooth
Bluetooth is a proprietary open wireless protocol for exchanging data over short distances (using short length radio waves) from fixed and mobile devices.
It connects PCs to devices, such as printer and fairly low cost to implement.
Terrestrial microwave
Earthbound microwave systems transmit high-speed radio signals.
Follows a line-of-sight path between relay systems spaced about 30 miles apart.
Microwave antenna is placed on top of buildings.
It must transmit in straight line with no obstructions.
Communications satellites
A communications satellite (sometimes abbreviated to COMSAT) is an artificial satelite stationed in space for the purpose of telecommunications.
Space station that receives microwave signals from earth-based station, amplifies signals, and broadcasts signals back to any number of earth-based stations.
Example: GPS, ASTRO
