ANSWERS TO QUESTIONS Q1. THROUGH Q13.

A1. Fiber optics is the branch of optical technology concerned with the transmission of radiant power (light energy) through fibers.
A2. The basic functions of a fiber optic data link are to convert an electrical input signal to an optical signal, send the optical signal over an optical fiber, and convert the optical signal back to an electrical signal.
A3. Transmitter, optical fiber, and receiver.
A4. Scattering, absorption, and dispersion.
A5. Noise obscures or reduces the quality of the signal.
A6. Loss is the decrease in the amount of light reaching the end of the fiber.
A7. Impurities in the fiber material caused the signal loss in optical fibers. The basic fiber material did not prevent the light signal from reaching the end of the fiber.
A8. By removing the impurities from optical fiber.
A9. Multimode and single mode fibers.
A10. Single mode fiber.
A11. Larger fiber core and higher fiber numerical aperture (NA).
A12. Trade-offs in fiber properties, types of connections, optical sources, and detector types in military and subscriber-loop applications.
A13. Advantages of fiber optics are improved system performance, immunity to electrical noise, signal security, electrical isolation, reduced size and weight, environmental protection, and overall system economy.