Communication Technologies and Signal Losses

This lesson explores the evolution of long-distance communication, starting from the telegraph to modern fiber optic cables. It covers the historical development of communication technologies, including the laying of submarine and transatlantic cables. The lesson also delves into the design considerations for these cables, focusing on bandwidth and noise. Additionally, it discusses the various types of losses in optical fibers and their impact on signal attenuation, concluding with challenges in quantum communication.

What was the primary method of communication before the telegraph?

• Letters

• Internet

• Television

• Radio

In what year was the first successful transatlantic telegraphic cable laid?

• 1902

• 1850

• 1866

• 1871

What was the capacity of the TAT-1 telephone cable?

• 150,000 conversations

• 51 conversations

• 8,000 conversations

• 40,000 conversations

Which technology increased the bandwidth to the equivalent of 40,000 telephone conversations?

• TAT-1

• TAT-9

• TAT-7

• TAT-8

What does bandwidth determine in a communication cable?

• The weight of the cable

• The color of the cable

• The amount of information it can carry

• The length of the cable

What is the speed of data transmission in a standard cable over 6,600 kilometers?

• 1 petabit per second

• 65 terabits per second

• 150 terabits per second

• 10 terabits per second

Which of the following is NOT a source of signal loss in optical fibers?

• Dispersion

• Absorption

• Reflection

• Scattering

What happens to a signal as it becomes attenuated?

• It becomes faster

• It changes color

• It loses power

• It gains power

What is the first step in overcoming signal losses in optical fibers?

• Changing cable color

• Increasing cable length

• Reducing cable weight

• Understanding dispersion

What challenge do signal losses present in quantum communication?

• Decreased reliability

• Simpler design

• Higher costs

• Increased speed