Coaxial Cable

Coaxial cables, commonly called coax, are copper cables with metal shielding designed to provide immunity against noise and greater bandwidth. Coax can transmit signals over larger distances at a higher speed as compared to twisted pair cables.

Structure of Coaxial Cables

Coax has a central core of stiff copper conductor for transmitting signals.  This is covered by an insulating material. The insulator is encased by a closely woven braided metal outer conductor that acts as a shield against noise. The outer conductor is again enclosed by a plastic insulating cover. The structure is shown in the following figure −

Categories of Coaxial Cables

Coaxial cables are categorized into three types as per radio government (RG) ratings −

• RG – 59: Has impedance of 75W and used in cable TV
• RG – 58: Has impedance of 50W and used in thin Ethernet
• RG – 11: Has impedance of 50W and used in thick Ethernet

Applications of Coaxial Cables

• In analog telephone networks: A single coaxial network can carry about 10,000 voice signals.
• In digital telephone networks: A coax has a data rate of 600 Mbps.
• In cable TV networks
• In traditional Ethernet LANs
• In MANs