Engineering Homework Help

George Mason University Fundamental Principles of Communications Questions

Get Your Custom Essay Written From Scratch
We have worked on a similar problem. If you need help click order now button and submit your assignment instructions.
Just from $13/Page
Order Now


QUESTION 1

undefined

  • Radio Frequency (RF) signals are a subset of the electromagnetic (EM) spectrum. Optical signals are also a subset of the EM spectrum.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 2

undefined

  • Select the correct statement(s) regarding the difference between analog and digital signals.

undefined

a. analog signals are used more extensively in modern computer systems compared to digital signals

b. digital signals are represented by logical and discrete values (i.e., “0” and “1”) and therefore logical bits must be grouped together to represent symbols

c. digital signals are more accurate than analog signals; this is why digital music sounds much better

d. analog networks easily fit into the OSI Reference Model

undefined

10 points

undefined

QUESTION 3

undefined

  • By viewing a signal in the frequency domain you can determine which of the following:

undefined

a. the frequency and period of the signal

b. the signal’s bandwidth and whether it is a traverse of longitudinal wave

c. signal amplitude and occupied signal bandwidth

d. signal amplitude and sinusoidal period

undefined

10 points

undefined

QUESTION 4

undefined

  • Which of the following are considered “unguided” mediums?

undefined

a. copper wire, optical fiber

b. vacuum of space, atmosphere

c. conductive wiring, air molecules

d. none of the above

undefined

10 points

undefined

QUESTION 5

undefined

  • Determine the signal frequency bandwidth given the following: lowest frequency equals 4 Hz and highest frequency equals 22 kHz.

undefined

undefined

a. 4Hz

b. 22 kHz

c. 24 kHz

d. 21,996 Hz

undefined

10 points

undefined

QUESTION 6

undefined

  • Select the correct statement(s) regarding electrical and electromagnetic (EM) information/signal waves.

undefined

a. an electrical signal travelling through a guided conductive wire will create a surrounding EM signal wave

b. electrical and EM signals carrying information will have an associated bandwidth that can be seen in the frequency domain

c. electrical signals consist of moving electrons through conductive medium, while EM wave consist of electrical and magnetic energy fields

d. all are correct statements

undefined

10 points

undefined

QUESTION 7

undefined

  • OSI is a seven-layered framework used to help define and organize the responsibilities of protocols used for network communications. It does not specifically identify which standards should be used within each layer.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 8

undefined

  • Select the OSI layer responsible for data exchange within a common network (e.g., Ethernet LAN).

undefined

a. Physical Layer 1

b. Data Link Layer 2

c. Network Layer 3

d. Transport Layer 4

undefined

10 points

undefined

QUESTION 9

undefined

  • Select the OSI layer responsible for the mechanical and electrical interfaces between devices in a data network.

undefined

a. Physical Layer 1

b. Data Link Layer 2

c. Network Layer 3

d. Transport Layer 4

undefined

10 points

undefined

QUESTION 10

undefined

  • Select the correct statement regarding the OSI Reference Model.

undefined

a. analog signals only occupy the first three layers of the OSI RM

b. the Network Layer is responsible for end-to-end connectivity over disparate “common networks”

c. the OSI Reference Model identifies and approves the standards that must be used in each layer in order to ensure interoperability

d. the OSI Reference Model is identical to TCP/IP

undefined

10 points

undefined

QUESTION 11

undefined

  • Select the correct statement(s) regarding partial mesh networks.

undefined

a. the number of links connecting nodes in a partial mesh network depends upon the availability and reliability requirements of the network

b. switches play an integral role in a partial mesh network, where several paths through the network are available

c. redundant links and switches are used to improve the availability and reliability of partial mesh networks

d. all of the statements are correct

undefined

10 points

undefined

QUESTION 12

undefined

  • Identify the correct statement(s) regarding dedicated circuits.

undefined

a. dedicated circuits provide point-to-point 24/7 access between communicating points

b. the availability of a dedicated circuit to the subscriber is very high

c. dedicated circuits are costly and cannot be easily expanded to include additional nodes

d. all statements are correct

undefined

10 points

undefined

QUESTION 13

undefined

  • A switched circuit is one in which a user maintains the physical path through a network during the period of a call. Once the user’s call is complete, the communications path is made available to other users.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 14

undefined

  • A virtual circuit enables the sharing of physical links by numerous users. Time division multiplexing (TDM) and packet switching techniques are ways in which virtual circuit can be created.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 15

undefined

  • Select the correct statement(s) regarding connectionless and connection-oriented networks.

undefined

a. packet networks support either connection-oriented or connectionless circuits

b. A connection must be established prior to exchanging data when using a connectionless circuit

c. packets must contain source and destination addresses in a connection-oriented circuit

d. all statements are correct

undefined

10 points

undefined

QUESTION 16

undefined

  • Identify the device that combines multiple time slots or frequency channels into an aggregate for transmission.

undefined

a. multiplexer

b. modem

c. repeater

d. switch

undefined

10 points

undefined

QUESTION 17

undefined

  • Two-way PTT (Push-To-Talk) radio is an example of:

undefined

a. Simplex Communications

b. Half Duplex Communications

c. Full Duplex Communications

d. Complex Communications

undefined

10 points

undefined

QUESTION 18

undefined

  • A telephone is an example of:

undefined

a. Simplex Communications

b. Half Duplex Communications

c. Full Duplex Communications

d. Complex Communications

undefined

10 points

undefined

QUESTION 19

undefined

  • Either acoustic or electromagnetic signals can be used to communicate to satellites in the vacuum of space.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 20

undefined

  • Given a wavelength of λ=1000 meters, determine the frequency and signal time period.

undefined

a. f=30 kHz, T=3.34E-6 seconds

b. f=300 kHz, T=3.34E-6 seconds

c. f=3000 kHz, T=3.34E-8 seconds

d. f=30,000 kHz, T=3.34E-9 seconds

undefined

10 points

undefined

QUESTION 21

undefined

  • 1000 MHz (1000E6) is equivalent to:

undefined

a. 1000kHz

b. 10GHz

c. 1GHz

d. 1THz

undefined

10 points

undefined

QUESTION 22

undefined

  • Given the following parameters, determine the correct sinusoidal equation for a sine wave: f=1kHz, A=5v, φ (phase angle)=+π radians.

undefined

a. 1sin(2π5t – π)

b. 5sin(2π1000t)

c. 5sin(2π1000t + π)

d. 5sin(2π1t + π)

undefined

10 points

undefined

QUESTION 23

undefined

  • Identify the correct equation that describe the relationship between a sine and cosine wave.

undefined

a. v(t) = A sin (2πft + π/2) = A cos (2πft)

b. v(t) = A sin (2πft) = A cos (2πft + π/2)

c. v(t) = A sin (2πft ) = A cos (2πft)

d. v(t) = A sin (2πft – π/2) = A cos (2πft)

undefined

10 points

undefined

QUESTION 24

undefined

  • In unguided medium (free space), the electromagnetic (EM) signal wave spreads as it leaves the transmit antenna. Since the power of the EM signal resides at the surface area of the wave front, signal power is described as signal power density (i.e., watts per area). As the signal propagates away from the transmitter, power density decreases, and attenuation is experienced.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 25

undefined

  • What is correct regarding an ideal isotropic antenna?

undefined

a. An ideal isotropic antenna is a highly efficient antenna used extensively in today’s communication systems

b. An ideal isotropic antenna is a specialized antenna used to direct EM signal energy towards a specific direction

c. An ideal isotropic antenna is a theoretical antenna that does not exist in practice, but is useful in explaining power density and unguided EM signal attenuation

d. None of the above are correct statements

undefined

10 points

undefined

QUESTION 26

undefined

  • Select the correct statement regarding modulation/demodulation.

undefined

a. the passband signal is combined with the carrier wave to produce a baseband which operates at a higher frequency

b. the carrier signal is combined with the passband wave to produce a baseband which operates at a higher frequency

c. the passband signal is combined with the baseband wave to produce a carrier which operates at a higher frequency

d. the baseband signal is combined with the carrier wave to produce a passband which operates at a higher frequency

undefined

10 points

undefined

QUESTION 27

undefined

  • Select the correct statement(s) regarding optical signals.

undefined

a. Optical signals are susceptible to radio frequency interference (RFI)

b. Although optical signals are part of the electromagnetic spectrum, they have different properties/characteristics and operate at higher frequencies than RF signals

c. Although optical signals are in the THz range, an RF antenna tuned to the proper frequency can collect an optical signal

d. All are correct statements

undefined

10 points

undefined

QUESTION 28

undefined

  • Convert 120E3 mW to dBm

undefined

a. 30 dBm

b. 20.8 dBm

c. 50.8 dBm

d. 80.8 dBm

undefined

10 points

undefined

QUESTION 29

undefined

  • Convert 300 watts to dBm

undefined

a. 54.77 dBm

b. 24.77 dBm

c. 300 dBm

d. 24.77 dBW

undefined

10 points

undefined

QUESTION 30

undefined

  • Convert 765 watts to dBm

undefined

a. 58.84 dBm

b. 28.84 dBm

c. 300 dBm

d. 24.77 dBW


QUESTION 1

undefined

  • Radio Frequency (RF) signals are a subset of the electromagnetic (EM) spectrum. Optical signals are also a subset of the EM spectrum.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 2

undefined

  • Select the correct statement(s) regarding the difference between analog and digital signals.

undefined

a. analog signals are used more extensively in modern computer systems compared to digital signals

b. digital signals are represented by logical and discrete values (i.e., “0” and “1”) and therefore logical bits must be grouped together to represent symbols

c. digital signals are more accurate than analog signals; this is why digital music sounds much better

d. analog networks easily fit into the OSI Reference Model

undefined

10 points

undefined

QUESTION 3

undefined

  • By viewing a signal in the frequency domain you can determine which of the following:

undefined

a. the frequency and period of the signal

b. the signal’s bandwidth and whether it is a traverse of longitudinal wave

c. signal amplitude and occupied signal bandwidth

d. signal amplitude and sinusoidal period

undefined

10 points

undefined

QUESTION 4

undefined

  • Which of the following are considered “unguided” mediums?

undefined

a. copper wire, optical fiber

b. vacuum of space, atmosphere

c. conductive wiring, air molecules

d. none of the above

undefined

10 points

undefined

QUESTION 5

undefined

  • Determine the signal frequency bandwidth given the following: lowest frequency equals 4 Hz and highest frequency equals 22 kHz.

undefined

undefined

a. 4Hz

b. 22 kHz

c. 24 kHz

d. 21,996 Hz

undefined

10 points

undefined

QUESTION 6

undefined

  • Select the correct statement(s) regarding electrical and electromagnetic (EM) information/signal waves.

undefined

a. an electrical signal travelling through a guided conductive wire will create a surrounding EM signal wave

b. electrical and EM signals carrying information will have an associated bandwidth that can be seen in the frequency domain

c. electrical signals consist of moving electrons through conductive medium, while EM wave consist of electrical and magnetic energy fields

d. all are correct statements

undefined

10 points

undefined

QUESTION 7

undefined

  • OSI is a seven-layered framework used to help define and organize the responsibilities of protocols used for network communications. It does not specifically identify which standards should be used within each layer.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 8

undefined

  • Select the OSI layer responsible for data exchange within a common network (e.g., Ethernet LAN).

undefined

a. Physical Layer 1

b. Data Link Layer 2

c. Network Layer 3

d. Transport Layer 4

undefined

10 points

undefined

QUESTION 9

undefined

  • Select the OSI layer responsible for the mechanical and electrical interfaces between devices in a data network.

undefined

a. Physical Layer 1

b. Data Link Layer 2

c. Network Layer 3

d. Transport Layer 4

undefined

10 points

undefined

QUESTION 10

undefined

  • Select the correct statement regarding the OSI Reference Model.

undefined

a. analog signals only occupy the first three layers of the OSI RM

b. the Network Layer is responsible for end-to-end connectivity over disparate “common networks”

c. the OSI Reference Model identifies and approves the standards that must be used in each layer in order to ensure interoperability

d. the OSI Reference Model is identical to TCP/IP

undefined

10 points

undefined

QUESTION 11

undefined

  • Select the correct statement(s) regarding partial mesh networks.

undefined

a. the number of links connecting nodes in a partial mesh network depends upon the availability and reliability requirements of the network

b. switches play an integral role in a partial mesh network, where several paths through the network are available

c. redundant links and switches are used to improve the availability and reliability of partial mesh networks

d. all of the statements are correct

undefined

10 points

undefined

QUESTION 12

undefined

  • Identify the correct statement(s) regarding dedicated circuits.

undefined

a. dedicated circuits provide point-to-point 24/7 access between communicating points

b. the availability of a dedicated circuit to the subscriber is very high

c. dedicated circuits are costly and cannot be easily expanded to include additional nodes

d. all statements are correct

undefined

10 points

undefined

QUESTION 13

undefined

  • A switched circuit is one in which a user maintains the physical path through a network during the period of a call. Once the user’s call is complete, the communications path is made available to other users.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 14

undefined

  • A virtual circuit enables the sharing of physical links by numerous users. Time division multiplexing (TDM) and packet switching techniques are ways in which virtual circuit can be created.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 15

undefined

  • Select the correct statement(s) regarding connectionless and connection-oriented networks.

undefined

a. packet networks support either connection-oriented or connectionless circuits

b. A connection must be established prior to exchanging data when using a connectionless circuit

c. packets must contain source and destination addresses in a connection-oriented circuit

d. all statements are correct

undefined

10 points

undefined

QUESTION 16

undefined

  • Identify the device that combines multiple time slots or frequency channels into an aggregate for transmission.

undefined

a. multiplexer

b. modem

c. repeater

d. switch

undefined

10 points

undefined

QUESTION 17

undefined

  • Two-way PTT (Push-To-Talk) radio is an example of:

undefined

a. Simplex Communications

b. Half Duplex Communications

c. Full Duplex Communications

d. Complex Communications

undefined

10 points

undefined

QUESTION 18

undefined

  • A telephone is an example of:

undefined

a. Simplex Communications

b. Half Duplex Communications

c. Full Duplex Communications

d. Complex Communications

undefined

10 points

undefined

QUESTION 19

undefined

  • Either acoustic or electromagnetic signals can be used to communicate to satellites in the vacuum of space.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 20

undefined

  • Given a wavelength of λ=1000 meters, determine the frequency and signal time period.

undefined

a. f=30 kHz, T=3.34E-6 seconds

b. f=300 kHz, T=3.34E-6 seconds

c. f=3000 kHz, T=3.34E-8 seconds

d. f=30,000 kHz, T=3.34E-9 seconds

undefined

10 points

undefined

QUESTION 21

undefined

  • 1000 MHz (1000E6) is equivalent to:

undefined

a. 1000kHz

b. 10GHz

c. 1GHz

d. 1THz

undefined

10 points

undefined

QUESTION 22

undefined

  • Given the following parameters, determine the correct sinusoidal equation for a sine wave: f=1kHz, A=5v, φ (phase angle)=+π radians.

undefined

a. 1sin(2π5t – π)

b. 5sin(2π1000t)

c. 5sin(2π1000t + π)

d. 5sin(2π1t + π)

undefined

10 points

undefined

QUESTION 23

undefined

  • Identify the correct equation that describe the relationship between a sine and cosine wave.

undefined

a. v(t) = A sin (2πft + π/2) = A cos (2πft)

b. v(t) = A sin (2πft) = A cos (2πft + π/2)

c. v(t) = A sin (2πft ) = A cos (2πft)

d. v(t) = A sin (2πft – π/2) = A cos (2πft)

undefined

10 points

undefined

QUESTION 24

undefined

  • In unguided medium (free space), the electromagnetic (EM) signal wave spreads as it leaves the transmit antenna. Since the power of the EM signal resides at the surface area of the wave front, signal power is described as signal power density (i.e., watts per area). As the signal propagates away from the transmitter, power density decreases, and attenuation is experienced.

undefined

True

undefined

False

undefined

10 points

undefined

QUESTION 25

undefined

  • What is correct regarding an ideal isotropic antenna?

undefined

a. An ideal isotropic antenna is a highly efficient antenna used extensively in today’s communication systems

b. An ideal isotropic antenna is a specialized antenna used to direct EM signal energy towards a specific direction

c. An ideal isotropic antenna is a theoretical antenna that does not exist in practice, but is useful in explaining power density and unguided EM signal attenuation

d. None of the above are correct statements

undefined

10 points

undefined

QUESTION 26

undefined

  • Select the correct statement regarding modulation/demodulation.

undefined

a. the passband signal is combined with the carrier wave to produce a baseband which operates at a higher frequency

b. the carrier signal is combined with the passband wave to produce a baseband which operates at a higher frequency

c. the passband signal is combined with the baseband wave to produce a carrier which operates at a higher frequency

d. the baseband signal is combined with the carrier wave to produce a passband which operates at a higher frequency

undefined

10 points

undefined

QUESTION 27

undefined

  • Select the correct statement(s) regarding optical signals.

undefined

a. Optical signals are susceptible to radio frequency interference (RFI)

b. Although optical signals are part of the electromagnetic spectrum, they have different properties/characteristics and operate at higher frequencies than RF signals

c. Although optical signals are in the THz range, an RF antenna tuned to the proper frequency can collect an optical signal

d. All are correct statements

undefined

10 points

undefined

QUESTION 28

undefined

  • Convert 120E3 mW to dBm

undefined

a. 30 dBm

b. 20.8 dBm

c. 50.8 dBm

d. 80.8 dBm

undefined

10 points

undefined

QUESTION 29

undefined

  • Convert 300 watts to dBm

undefined

a. 54.77 dBm

b. 24.77 dBm

c. 300 dBm

d. 24.77 dBW

undefined

10 points

undefined

QUESTION 30

undefined

  • Convert 765 watts to dBm

undefined

a. 58.84 dBm

b. 28.84 dBm

c. 300 dBm

d. 24.77 dBW