5.1 TELECOMMUNICATION SYSTEMS Flashcards
_________ Used to convey messages from about 700 B.C.E.
carrier pigeons
It is where the first long-distance communication systems were based on (e.g. drums and horns, smoke signals and beacon fires)
signals of sound and light
________ alerted the British of the arrival of the Spanish Armada in 1588 C.E.
signal fires
The Chinese used _____ as signals to warn of an imminent attack on the Great Wall
rockets
Native Americans communicated by covering and uncovering a _____ with a blanket to produce smoke signals or by beating drums
bonfire
The British Navy sent signals at night by raising and lowering a lantern, which coincidentally was the same way ________ was signaled with news of the arrival of the British.
Paul Revere
In instances when clear vision was difficult (e.g., fog), bells or _____ and _______ sent signals.
whistles and fired weapons
Used in traditional long-distance communication until almost 1800
Horse-mounted Dispatch Riders
Developed an optical telegraph (semaphore) system of Stations built on rooftops or towers that were visible from a great distance in 1793
Frenchman Claude Chappe
Each _________ consisted of a column-like tower with a moveable beam. Attached to the beam were two moveable arms. o The beam and arms were swiveled with ropes, conveying different
semaphore station
This system allowed the French to send a concise message over ______ (160 km) in less than 5 min as long as visibility was good.
100 miles
Developed another type of optical telegraph system with ten collapsible iron shutters, which when placed in various positions formed combinations of numbers that were translated into letters, words, or phrases
Swede A, N. Edelcrantz
__________ were also used in Boston, New York City, and San Francisco at that time.
Crude Semaphore Systems
Transmitted the first practical electrical signal in 1830
Joseph Henry
Patented the first functional electrical communication system in 1831
Samuel Morse
An electric telegraph with its system of electrical impulses identified as dots and dashes that eventually became known as _____
Morse Code
The first message sent by electric telegraph was _______________ from the Supreme Court Room in the U.S. Capitol to the railway depot at Baltimore on May 24, 1844.
“What hath God wrought,”
in 1861, there were over _____ telegraph offices in operation across America and the East and West coasts were connected
2000
Invented an electrical speech machine that transmitted voice over wires and became known as the telephone, on March 10, 1876, in Boston, Massachusetts
Alexander Graham Bell
________ were the first words accidentally spoken into the new invention.
“Mr. Watson, come here, I want you!”
In 1880, the first telephone company, ________, was formed and over 30 000 phones were in use.
American Bell
In ____, over ten million American Bell System telephones were in service.
1920
Italian inventor who demonstrated the first radio transmission in 1895 that was received out of a line of sight (about 2 miles) on the grounds of his family estate in Italy.
Gugliemo Marconi
Six years later in Newfoundland, Canada, Marconi’s radio received a ______ that was sent across the Atlantic Ocean by one of his associates in Cornwall, England. The signal was an “S” sent in Morse Code format, “dot, dot, dot.” It demonstrated that radio waves could bounce off the upper atmosphere.
weak signal
Italian physicist who invented a pantelegraph in 1865 for transmitting pictures, the first commercial fax system.
Giobanni Caselli
The first transmission of pictures over ______ wires was publicly demonstrated on May 19, 1924.
telephone
On January 23, 1926, __________ of Scotland gave the first public demonstration of a mechanical television with images of living human faces, not just outlines or silhouettes.
John Logie Baird
Is the transmission, emission, or reception of Signs, signals, writing, images, sounds, or information of any nature by wire, radio, optical, or other electromagnetic systems
Telecommunication
Uses electricity, light (visible and infrared), or radio waves to transmit signals that carry voice and data transmissions
Telecommunication System
Is a telecommunications device that functions as a transmitter and receiver
Transceiver
Is the range between the highest and lowest frequencies of transmission, measured in hertz (Hz), cycles per second. Bandwidth varies with the type and method of transmission. It is a measure of the information capacity.
Bandwidth
The conversion of useful sound or data into electrical impulses. Capable of transmitting both voice and nonvoice messages
Analog Transmission
__________ are bulky when transmitted in an analog format, so they cannot be transmitted rapidly.
Nonvoice transmissions
Involves a transmission of a signal that varies in voltage to represent one of two separate states
Digital Transmission
Is a collection of communication a equipment and devices that are interconnected so they can communicate in order to share data, hardware, and software or perform an electronic function
Telecommunication Network
The network includes a series of connecting points called ____
nodes
Describes the configuration of a network, including its nodes, connecting cables and equipment.
Topology
Connects each workstation (node) to a single cable trunk.
Bus Topology
All workstations (nodes) are connected to a central unit called a hub
Star Topography
Cables that extend from the hub to the terminal without splicing or other connections.
Home runs
Connects workstation equipment and devices in a point-to-point serial manner in an unbroken circular configuration
Ring Topography
LAN
local area network
MAW
metropolitan area network
WAN
wide area network
Is the most common medium through which voice and data usually move from one network device to another
Cable
Devices that connect cable to the network device (eé.g., computer, printer, entertainment center, and so forth).
Connectors
Is the most common medium through which voice and data usually Has been the principal telecommunications transmission medium.
Copper Wiring
_______ has four pairs of wires inside the jacket
Twisted Pair Cable
_______ comes with each pair uniquely color coded when it is packaged in multiple pairs.
Twisted Pair
A twisted pair is enclosed in a shield. An outer covering or shield is added to the ordinary twisted pair wires; the shield functions as a ground
Shielded Twisted Pair (STP) Wiring
Consists of multiple pairs of twisted insulated copper conductors bound in a single sheath.
Unshielded Twisted Pair (UTP) Wiring
U.S. standard for wire conductor size applied to copper electrical power and telephone wiring.
American Wire Gauge (AWG)
_______ carries current more efficiently (because it has less electrical resistance over a specific length), a thicker wire is more efficient for longer distances.
Thicker Wire
Has two conductors: an inner solid wire surrounded by an outer braided metal sheath.
Coaxial Cable
In coaxial cable, ________ separates the two concentric conductors, and a _______ protects the entire cable.
insulation, hard casing
Also referred to as thinnet.
Thin Coaxial Cable
The ____ designation refers to specifications for thin coaxial cable
10base2
Also referred to as thicknet.
Thick Coaxial Cable
A type of coax cable with an additional outer copper braid insulated from signal carrying conductors
Triax Cable
_________ refers to the specifications for thick coaxial cable
10Base5
A type of communication transmission cable consisting of two center conductors surrounded by an insulating spacer, which in turn is surrounded by a tubular outer conductor (usually a braid, foil, or both).
Twin Axial Cable (Twinax)
________ is very effective at carrying many analog Signals at high frequencies.
Coaxial Cable
_______ has a much higher bandwidth to carry more data, and offers greater protection from noise and interference. It is highly resistant to signal interference and can support greater cable lengths between network devices than twisted pair copper cable
Coaxial Cable
__________ is widely used in cable television systems because it is capable of carrying many TV and radio Signals simultaneously.
High-capacity Coaxial Cable
The most common type of connector used with coaxial cables.
Bayonet Neil-Concelman (BNC) Connector
Are long, thin strands of very pure silicon glass or plastic about the diameter of a human hair.
Optical Fibers
the thin glass center of the fiber where the light travels
core
the outer material surrounding the core that reflects the light back into the core
cladding
a plastic coating that protects the fiber from damage and moisture
buffer coating
The cable’s outer sheathing that protects the optical cables
jacket
Bundles that are consist of hundreds or thousands of optical fibers
optical cables
A barrel shaped, similar to a BNC connector
ST connectors
Has a squared face and is easier to connect in a confined space.
SC Connectors
Decodes the signal and receives the light signal. Uses a photocell or photodiode to detect the light signal, decodes it, and sends an electrical signal to a computer, TV, or telephone.
Optical Receiver
Needed over long distances to boost the light signal.
Optical Regenerator
Term used to describe telecommunications in which electromagnetic waves carry the signal.
wireless
The operation of wireless devices or systems in homes and offices, and in particular, equipment connected to the Internet by the use of specialized modems.
Fixed Wireless Network
Has a wavelength of 650 nm which consists of a number of computers, each equipped with a wireless networking interface card.
Peer-to-peer
Has a computer or receiver that serves as the point at which the network is accessed.
Access point or base station
The use of technology in devices or systems that convey data through infrared radiation.
Infrared
__________ is electromagnetic energy at wavelengths somewhat longer than those of visible red light
Infrared Radiation
Uses radio waves to send and receive information, similar to a garage door opener, baby monitor, walkie-talkie, or portable phone
Radio Frequency
There must be a visually unobstructed straight-line path through space between the transmitter (source) and receiver (destination).
Line-of-sight Mode
Where the system can function when the source and destination are not directly visible to each other.
Diffuse Mode
Derived from the term wireless fidelity
WI-FI
The popular expression used to describe high frequency wireless local area network (WLAN) technology
WI-FI
A manner wherein a telecommunication signal is affected due to a telecommunication cable placed within an electromagnetic field.
Electromagnetic Interference
