Data and Signals Chapter 3
30 Questions
4 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What type of data takes on continuous values?

  • Periodic data
  • Composite data
  • Analog data (correct)
  • Digital data

    • What is a characteristic of a periodic signal?

  • It completes a pattern within a measurable time frame (correct)
  • It changes without exhibiting a pattern or cycle
  • It is a type of digital signal
  • It can have an infinite number of values in a range

    • What type of signal can have an infinite number of values in a range?

  • Digital signal
  • Nonperiodic signal
  • Periodic signal
  • Analog signal (correct)

    • What is a simple periodic analog signal?

    <p>A sine wave</p> Signup and view all the answers

    What type of data is typically used in data communications?

    <p>Only digital data</p> Signup and view all the answers

    What is a characteristic of a nonperiodic signal?

    <p>It changes without exhibiting a pattern or cycle</p> Signup and view all the answers

    What is the frequency of a signal that does not change at all?

    <p>Zero</p> Signup and view all the answers

    What is the phase of a sine wave that is offset 1/6 cycle with respect to time 0?

    <p>60°</p> Signup and view all the answers

    What is represented by a single spike in the frequency domain?

    <p>A single-frequency sine wave</p> Signup and view all the answers

    What is the result of decomposing a non-periodic composite signal using Fourier analysis?

    <p>A combination of sine waves with continuous frequencies</p> Signup and view all the answers

    What is the bandwidth of a composite signal?

    <p>The difference between the highest and the lowest frequencies</p> Signup and view all the answers

    Why is a single-frequency sine wave not useful in data communications?

    <p>Because it is not suitable for transmitting complex information</p> Signup and view all the answers

    What is the bandwidth of a periodic signal composed of five sine waves with frequencies of 100, 300, 500, 700, and 900 Hz?

    <p>800 Hz</p> Signup and view all the answers

    What are the lowest and highest frequencies of a nonperiodic composite signal with a bandwidth of 200 kHz and a middle frequency of 140 kHz?

    <p>40 kHz and 240 kHz</p> Signup and view all the answers

    How many bits are needed to represent each level of a digital signal with eight levels?

    <p>3 bits</p> Signup and view all the answers

    What is the minimum number of signal levels required for a digital signal to transmit 2 bits of information per level?

    <p>8 levels</p> Signup and view all the answers

    How many bits are needed to represent each level of a digital signal with nine levels?

    <p>3.17 bits</p> Signup and view all the answers

    What is the main difference between analog and digital signals?

    <p>Analog signals have a continuous range of values, while digital signals have discrete levels</p> Signup and view all the answers

    What is the name of the converter that changes digital signals to analog signals and vice versa?

    <p>Modem</p> Signup and view all the answers

    What is signal impairment caused by?

    <p>The imperfection of transmission media</p> Signup and view all the answers

    What happens to the signal as it travels through a transmission medium?

    <p>It changes its form or shape</p> Signup and view all the answers

    What is attenuation?

    <p>A loss of energy or reduction of amplitude</p> Signup and view all the answers

    What is the effect of a 3 dB loss on a signal's power?

    <p>It reduces the power by half</p> Signup and view all the answers

    What happens to the signal's power if it is increased 10 times after passing through an amplifier?

    <p>It becomes 10 times stronger</p> Signup and view all the answers

    Why do engineers use decibels to measure changes in signal strength?

    <p>Because decibel numbers can be added or subtracted when measuring several points</p> Signup and view all the answers

    What is thermal noise caused by?

    <p>The random motion of electrons in a wire</p> Signup and view all the answers

    What is the unit of measurement for the loss in a cable?

    <p>Decibels per kilometer</p> Signup and view all the answers

    What happens to the signal power when traveling through a cable with a loss of -0.3 dB/km?

    <p>It decreases by 0.3 dB/km</p> Signup and view all the answers

    What is crosstalk?

    <p>The effect of one wire on another</p> Signup and view all the answers

    What is the power of the signal at 5 km if the signal at the beginning of a cable has a power of 2 mW and a loss of -0.3 dB/km?

    <p>Less than 2 mW</p> Signup and view all the answers

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser