It is the standard used in CATV systems, which can be transmitted either by analog signals using frequency division multiplexing or by digital signals. Coaxial cable is more expensive than twisted pair, but its anti-interference performance is stronger than that of twisted pair cable. When you need to connect more devices and the communication capacity is very large, you can choose coaxial cable.
(COAXIAL, CABLE) a cable consisting of concentric concentric conductors that are insulated from each other: the inner conductor is copper wire, and the outer conductor is copper tube or net. The electromagnetic field is closed between the inner and outer conductors, so the radiation loss is small and the interference is small. Often used in transmitting multichannel telephones and televisions.
The name of the coaxial cable is related to its structure. Coaxial cable is also one of the most common transmission media in lan. It is used to transmit information on a conductor is in accordance with the outer conductor of a layer of the cylindrical inner conductor (a thin core) outside, between two conductors with insulating material isolated from each other for the core structure, the outer conductor and the central axis of the circle in the same axis, so called coaxial cable the design of coaxial cable, it is to prevent the transfer of external electromagnetic interference abnormal signal.