Optical communication using fibers is performed in the frequency range of:

CONCEPT:

The bandwidth of Transmission Medium:

• Similar to message signals, different types of transmission media offer different bandwidths.
• The commonly used transmission media are wire, free space, and fiber optic cable.
• Coaxial cable is a widely used wire medium, which offers a bandwidth of approximately 750 MHz.
• Such cables are normally operated below 18 GHz.
• Communication through free space using radio waves takes place over a very wide range of frequencies: from a few hundreds of kHz to a few GHz.
• This range of frequencies is further subdivided and allocated for various services as indicated in the given table.
• Optical communication using fibers is performed in the frequency range of 1 THz to 1000 THz (microwaves to ultraviolet). An optical fiber can offer a transmission bandwidth in excess of 100 GHz.
• Spectrum allocations are arrived at by an international agreement. The International Telecommunication Union (ITU) administers the present system of frequency allocations.

EXPLANATION:

• Optical communication using fibers is performed in the frequency range of 1 THz to 1000 THz (microwaves to ultraviolet). Hence, option 3 is correct.