Coaxial cable is a kind of communication cable. The cable structure is a solid copper core and a layer of insulating material. This layer of insulating material is surrounded by densely woven mesh conductors, and the net is covered with a layer of protective material. Two kinds of widely used coaxial cables are 50 ohm cables, which are used for digital transmission. Because they are mostly used for baseband transmission, they are also called baseband coaxial cables; the other is 75 ohm cables, which are used for analog transmission. Coaxial cable can support extremely wide bandwidth and has excellent noise suppression characteristics, so it can transmit data, voice and video at the same time. There are two kinds of coaxial cables in Ethernet network, one is thick cable (Thicknet) and the other is Thin cable
Coaxial cable (Coaxial) refers to a cable with two concentric conductors, and the conductor and the shielding layer share the same axis. The most common coaxial cable consists of a copper conductor isolated by an insulating material. Outside of the inner insulating material is another layer of ring conductor and its insulator, and then the entire cable is covered by a polyvinyl chloride or Teflon material sheath.
At present, there are two types of commonly used coaxial cables: 50Ω and 75Ω coaxial cables.
75Ω coaxial cable is often used in CATV network, so it is called CATV cable, and its transmission bandwidth can reach 1GHz. At present, the transmission bandwidth of commonly used CATV cable is 750MHz.
