Coaxial cables are also known as coax cables. Coaxial cables are used to transmit radio frequency (RF) signals. It has relatively low emission losses and it provides protection from electromagnetic interference. This allows signals with low power to be transmitted over longer distances. A Coaxial cable is comprised of an inner core, insulator, shield, and outer cover. The reason why it is called coaxial is simply because these sections all share the same axis. There are all sorts of different types of coaxial cable and each one has different physical and electronic properties designed for specific tasks. It is usually used for carrying cable television signals along suburban streets and into homes.

Construction

Firstly the inner core of regular coaxial cable is usually solid copper between one and two millimeters thick, but at times some types use wire strands for improved flexibility. The dielectric insulator is either foam, solid plastic, or an air gap created by plastic spacers. The shielding is usually made from copper braid and completely surrounds the insulator layer. Normally the shielding is usually braided to provide flexibility but it can also be made from aluminum film. The shielding is covered by a thin plastic layer for protection.

How Coaxial Cable It Works

Coaxial cable is more like an antenna than an ordinary regular cable this is so because it carries an electromagnetic wave between the inner core and the shielding. Coaxial cable has superior signal quality because the shielding that mostly prevents interference from reaching the signal. Coaxial connectors are designed to have the same impedance as the cable and to maintain its shielding. The main connector types are the BNC connector used for computer networking, and the F connector used for cable television. Cable terminators are closed connectors that are placed on all open ends of a coaxial cable network to minimize signal loss and interference.

Why Use Coaxial Cable?

Coaxial cable has quite a lot of advantages over twisted-pair cables and other types of cables but unfortunately it also has a few disadvantages. It has a large frequency range which allows it to carry multiple signals. This makes it ideal for carrying many cable television broadcasts. Each channel also has greater bandwidth that allows for high definition video. The shielding reduces crosstalk and other interference. This allows for greater cable lengths between amplifiers. Despite these advantages coaxial cables are more expensive to install and they use a network topology that is prone to congestion.

Applications

Coaxial cables are used to carry television signals and to connect video equipment together. Another use of coaxial cables is to carry radio signals and connect receivers, transmitters, and antennas together. Shorter lengths of coaxial cables are also used for connecting devices with test equipment, like signal generators. Coaxial cable were once widely used to connecting computer in local area networks (LANs) but it was replaced by twisted-pair cable. Nonetheless cable broadband remains popular and uses the same coaxial cable that cable television uses. Most coaxial cable networks will eventually be replaced by superior fiber optic networks.