Description
Coaxial cable conducts electrical signal using an inner conductor (usually a flexible solid or stranded copper wire) surrounded by an insulating layer and all enclosed by a shield layer, typically a woven metallic braid; the cable is often protected by an outer insulating jacket. Normally, the shield is kept at ground potential and a voltage is applied to the center conductor to carry electrical signals. The advantage of coaxial design is that the electric and magnetic fields are confined to the dielectric with little leakage outside the shield. On the converse, electric and magnetic fields outside the cable are largely kept from causing interference to signals inside the cable. This property makes coaxial cable a good choice for carrying weak signals that cannot tolerate interference from the environment or for higher electrical signals that must not be allowed to radiate or couple into adjacent structures or circuits.
Common applications of coaxial cable include video and CATV distribution, RF and microwave transmission, and computer and instrumentation data connections.
The characteristic impedance of the cable is determined by the dielectric constant of the inner insulator and the radii of the inner and outer conductors. A controlled cable characteristic impedance is important because the source and load impedance should be matched to ensure maximum power transfer and minimum Standing Wave Ratio. Other important properties of coaxial cable include attenuation as a function of frequency, voltage handling capability, and shield quality.
Read more about this topic: Coaxial Cable
Famous quotes containing the word description:
“A sound mind in a sound body, is a short, but full description of a happy state in this World: he that has these two, has little more to wish for; and he that wants either of them, will be little the better for anything else.”
—John Locke (1632–1704)
“I fancy it must be the quantity of animal food eaten by the English which renders their character insusceptible of civilisation. I suspect it is in their kitchens and not in their churches that their reformation must be worked, and that Missionaries of that description from [France] would avail more than those who should endeavor to tame them by precepts of religion or philosophy.”
—Thomas Jefferson (1743–1826)
“The next Augustan age will dawn on the other side of the Atlantic. There will, perhaps, be a Thucydides at Boston, a Xenophon at New York, and, in time, a Virgil at Mexico, and a Newton at Peru. At last, some curious traveller from Lima will visit England and give a description of the ruins of St Paul’s, like the editions of Balbec and Palmyra.”
—Horace Walpole (1717–1797)