Copper coaxial cable for the hard-core, outsourcing a layer of insulating material. This layer of insulating material with a dense weave of the mesh conductor surround-network, and covered with a layer of protective material. There are two widely used coaxial cable. One is 50 ohm cable for digital transmission, as used for baseband transmission, also called baseband coaxial cable; the other is 75 ohm cable for analog transmission, the next section to talk about the broadband coaxial the cable. This difference is due to historical reasons, and not due to technical reasons or manufacturer.
Coaxial cable of this structure, it has high bandwidth and excellent noise rejection. The bandwidth depends on the length of coaxial cable. 1km of cable can reach 1Gb / s ~ 2Gb / s data transfer rate. You can also use a longer cable, but the transmission rate to lower or intermediate amplifier. Currently, a large number of coaxial cable to be replaced by optical fiber, but still widely used in cable TV and some local area network.
