Coaxial Cable
Coaxial cable, or coax for short, gets its name from the fact that there are two conductors that share the same axis. As shown in the figure, coaxial cable consists of:
• A copper conductor used to transmit the electronic signals.
• A layer of flexible plastic insulation surrounding a copper conductor.
• The insulating material is surrounded in a woven copper braid, or metallic foil, that acts as the second wire in the circuit and as a shield for the inner conductor. This second layer, or shield, also reduces the amount of outside electromagnetic interference.
• The entire cable is covered with a cable jacket to prevent minor physical damage.
There are different types of connectors used with coax cable.
Although UTP cable has essentially replaced coaxial cable in modern Ethernet installations, the coaxial cable design is used in:
• Wireless installations: Coaxial cables attach antennas to wireless devices. The coaxial cable carries radio frequency (RF) energy between the antennas and the radio equipment.
• Cable Internet installations: Cable service providers provide Internet connectivity to their customers by replacing portions of the coaxial cable and supporting amplification elements with fiber-optic cable. However, the wiring inside the customer's premises is still coax cable.