What is Coaxial cable ? What is application of Coaxial cable? What are advantages of Coaxial cable ?

COAXIAL CABLE :-

coaxial cable

* Definition of coaxial cable :- 

- A coaxial cable is a type of shielded and insulated copper cable that is used in to deliver TV services and computer networkto end users devices .                 
   - Coaxial cable is a type of copper cable specially built with a metal shield and other components engineered to block signal interference.

It was  implemented in the early 1940s for commercial purpose .

 It is used for both baseband and broadband data communication. services.

LAYER of coaxial cable :-

The ‘centre core’ is what carries the signal. The core can be a single solid wire, or stranded, or in high power/current applications it can be hollow (because of the skin effect means you don’t need to bother with conductor in the middle).

The ‘dielectric insulator’ not only separates the core from the shield, but provides the core with a consistent impedance (mostly capacitance) between core and shield. This in turn governs how high a frequency can be carried, and for what length of a coaxial cable (before being attenuated too much). The higher the dielectric constant of the insulator, the higher the frequency that can be carried by the core, &/or for a longer length.

The ‘metallic shield’ serves multiple purposes: one already mentioned above (known & consistent capacitance between core & shield), as well as preventing signal from escaping from the core conductor (ie. preventing radio broadcasts off the coax cable), and also preventing unwanted external noise or signals from impinging on the signal carried by the core conductor. So the shield works bi-directionally.

Finally the ‘plastic jacket’ protects the overall coaxial cable from its environment. In simple low-end applications this is just a single layer of plastic. But it can range all the way up to multiple layers of both insulating as well as metallic materials, to help make it more robust to water ingress, chemical corrosion, attack by wildlife, and physical strength for when men with axes and backhoe’s accidentally try to break it while digging for something else.

Application of coaxial cable :-

1. Wireless and antenna application(connecting from dish to television through co-axial cable. example: Dish TV,etc.)

2.RF and Microwave transmission

3.Video distribution

4.Cable television and cable internet

Advantages:-

- they are cheap to make 

- cheap to install 
- easy to modify 
- good bandwith 
- great channel capacity 
- noise immunity due to low error rate