Exploring Communication: Microwaves, Satellites, and Digital Signaling

The lecture covers communication systems using the electromagnetic spectrum, focusing on microwaves for mobile and satellite communication. It explains low-Earth and geostationary satellite systems, Bluetooth for short-range communication, and optical fibers for long-distance data transmission. The transition from analog to digital signals is discussed, highlighting the benefits of digital signaling for accurate data transmission.

What is the primary reason microwaves are used in mobile phones?

• They can penetrate walls and require short aerials.

• They are the cheapest form of communication.

• They have the longest wavelength in the spectrum.

• They are absorbed by the Earth's atmosphere.

What is a key characteristic of low-Earth orbit satellites?

• They are used exclusively for television broadcasting.

• They remain stationary above the equator.

• They travel at high speeds and have short orbital periods.

• They provide global coverage with a single satellite.

Why might Bluetooth not be suitable for connecting devices in different buildings?

• Bluetooth is only used for audio devices.

• Bluetooth signals are too strong and cause interference.

• Bluetooth signals cannot pass through walls.

• Bluetooth signals are weakened significantly when passing through walls.

What is the main advantage of using optical fibers in communication?

• They are cheaper than other communication methods.

• They are used exclusively for satellite communication.

• They can carry higher rates of data over long distances.

• They are easier to install than other cables.

What is a major drawback of analog signals in communication?

• They are immune to interference.

• They do not weaken over distance.

• They can pick up noise and become distorted.

• They are easier to regenerate accurately.

How is an analog signal converted into a digital signal?

• By amplifying the signal continuously.

• By increasing the signal's amplitude.

• By sampling the signal at regular intervals and converting it to binary.

• By reducing the signal's frequency.

What is a key benefit of digital signals over analog signals?

• Digital signals allow for more accurate transmission.

• Digital signals are more susceptible to noise.

• Digital signals are more expensive to transmit.

• Digital signals can only be used for short distances.

What happens to a digital signal when it is weakened during transmission?

• It automatically regenerates without any loss.

• It loses all data and cannot be recovered.

• It remains distinguishable between 1's and 0's.

• It becomes indistinguishable from noise.

What device is used to convert a digital signal back into an analog signal?

• Signal booster

• Analog-to-digital converter

• Signal amplifier

• Digital-to-analog converter

Why is digital signaling preferred for long-distance communication?

• It requires less power to transmit.

• It allows for increased data transmission rates and range.

• It is less expensive than analog signaling.

• It does not require any signal regeneration.