Coaxial cable, shown in Figure 1, is usually constructed of either copper or aluminum. It is used by cable television companies to provide service and for connecting the various components that make up satellite communication systems.
Coaxial cable (or coax) carries data in the form of electrical signals. It provides improved shielding compared to unshielded twisted-pair (UTP), so it has a higher signal-to-noise ratio and can therefore carry more data. However, twisted-pair cabling has replaced coax in LANs because, when compared to UTP, coax is physically harder to install, more expensive, and harder to troubleshoot.
Coaxial cable is enclosed in a sheath or jacket, as shown in Figure 2. There are several types of coaxial cable:
- Thicknet or 10BASE5 - Used in networks and operated at 10 Mb/s with a maximum length of 1640.4 ft. (500 m.)
- Thinnet 10BASE2 - Used in networks and operated at 10 Mb/s with a maximum length of 607 ft. (185 m.)
- RG-59 - Most commonly used for cable television in the United States
- RG-6 - Higher quality cable than RG-59, with more bandwidth and less susceptibility to interference
Cable service provider wiring inside a customer’s premises is coax. Several connecting methods are used to connect coaxial cable together. Two common connection types, shown in Figure 3, include:
- F series - Primarily used in television cable and antenna applications up to 1 GHz
- BNC - Designed for military use and also used in video and RF applications to 2 GHz
The F series connector has a standard thread pattern, but push-on designs are also available. The BNC uses a push, twist, and lock connector. Coaxial cable has no specific maximum bandwidth, and the type of signaling technology used determines the speed and limiting factors.