Name the common guided transmission media and give the physical description areas and transmission characteristics of any one of them.

The common guided transmission media are-

· Twisted pair cable

· Coaxial cable

· Optical cable

Coaxial cable:

Physical description: Consists two conductors i.e. inner & outer.

(i) Outer conductor is braided is braided shield

(ii) Inner conductor is solid metal

(iii) Separated by insulating material

(iv) Cover by padding

It is used over longer distances & support more stations on a shared line than twisted pair.

Figure-1: Shows physical construction of coaxial cable

Applications: Coaxial cable is the most versatile transmission media & is enjoying widespread use is a wide variety of applications. The most important of these are as follows-

(i) Television distribution

(ii) Long-distance telephone transmission

(iii) Short-run computer system links

(iv) LANs

Transmission characteristics: Coaxial cable is used to transmit both A & D signals, figure-2 shows that Coaxial Cable has frequency characteristics.

Figure-2 shows the frequency characteristics for cc.cc has higher frequencies & data rates than twisted pair because its shielded concentric constructions.

Coaxial cable is much less susceptible to interference & crosstalk than twisted pair. For long-distance transmission of analog signals amplifiers are heeded every few kilometers. For digital signaling repeaters are needed every kilometer or so on.