CDC 3D153 Volume 3 V3 (April 2013)
CDC 3D153 01 1206, Edit Code 02 (April 2013)
Volume 3 Units 1-5
Unit 1: Wideband Communications.
Unit 2: Satellite Communications Fundamentals.
Unit 3: Multichannel Satellite Principles.
Unit 4: Satellite Systems
Unit 5: Network Bandwidth Management.
Questions and Answers
- 1.
In the tropospheric scatter mode, the high power amplifier amplifies the radio frequency to
- A.
1 milliwatt.
- B.
1 watt.
- C.
100 watt.
- D.
1 kilowatt.
Correct Answer
D. 1 kilowatt.Explanation
In the tropospheric scatter mode, the high power amplifier is used to amplify the radio frequency signal. The power output required for this mode is typically high in order to overcome the attenuation caused by the scattering of the signal in the troposphere. The correct answer of 1 kilowatt indicates that a power output of 1000 watts is needed to ensure effective communication over long distances in this mode.Rate this question:
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- 2.
Which type of diversity requires two antennas, two receivers, and two transmitters?
- A.
Polarization.
- B.
Crossband.
- C.
Frequency.
- D.
Space.
Correct Answer
A. Polarization.Explanation
Polarization diversity requires two antennas, two receivers, and two transmitters. This is because polarization diversity involves transmitting and receiving signals with different polarizations. By using two antennas, receivers, and transmitters, the system can effectively capture and transmit signals with different polarizations, improving signal quality and reducing interference. Crossband diversity, frequency diversity, and space diversity do not require multiple antennas, receivers, and transmitters.Rate this question:
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- 3.
The MD–1026 digital data modem can interface up to four groups of, which type of signals?
- A.
Balanced non-return-to-zero (NRZ).
- B.
Conditioned diphase.
- C.
Unbalanced NRZ.
- D.
Isochronous.
Correct Answer
B. Conditioned diphase.Explanation
The MD-1026 digital data modem can interface up to four groups of conditioned diphase signals. Conditioned diphase encoding is a method of encoding digital data where each bit is represented by a transition in the middle of a bit period. This encoding scheme is commonly used in digital communication systems to ensure reliable data transmission and minimize errors. By supporting conditioned diphase signals, the MD-1026 modem can effectively interface with multiple data sources and facilitate efficient data transfer.Rate this question:
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- 4.
The trunk group multiplexer TD–1236 can multiplex up to
- A.
One group of the 512 Kbps data rate family.
- B.
One group of the 576 Kbps data rate family.
- C.
Four groups of the 512 Kbps data rate families or 576 Kbps data rate families.
- D.
Four groups of the 12 Kbps data rate families and 576 Kbps data rate families.
Correct Answer
C. Four groups of the 512 Kbps data rate families or 576 Kbps data rate families.Explanation
The trunk group multiplexer TD-1236 is capable of multiplexing four groups of either the 512 Kbps data rate families or the 576 Kbps data rate families. This means that it can handle a total of four groups, regardless of the specific data rate family.Rate this question:
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- 5.
Digital voice orderwire traffic that originates at the AN/TRC–170’s voice orderwire control unit, is encrypted by the
- A.
KY–68.
- B.
KY-58.
- C.
KY–84.
- D.
KY–81.
Correct Answer
B. KY-58.Explanation
The correct answer is KY-58. The KY-58 is used to encrypt digital voice orderwire traffic originating from the AN/TRC-170's voice orderwire control unit. This encryption ensures that the communication is secure and cannot be easily intercepted or understood by unauthorized individuals.Rate this question:
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- 6.
Which jack field in the AN/TRC–170’s baseband patch panel provides timing and data connections?
- A.
Middle.
- B.
Center.
- C.
Upper.
- D.
Lower.
Correct Answer
C. Upper.Explanation
The correct answer is "Upper." In the AN/TRC-170's baseband patch panel, the upper jack field provides both timing and data connections.Rate this question:
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- 7.
The tropospheric scatter modem processes mission traffic at data rates of 128 through 4,096 Kbps, within which data rate family?
- A.
512 Kbps.
- B.
576 Kbps.
- C.
1,024 Kbps.
- D.
1,152 Kbps.
Correct Answer
A. 512 Kbps.Explanation
The tropospheric scatter modem processes mission traffic at data rates ranging from 128 to 4,096 Kbps. Among the given options, the closest data rate family to this range is 512 Kbps.Rate this question:
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- 8.
Which unit in the AN/TRC–170 terminal contains the rubidium standard?
- A.
Electrical synthesizer.
- B.
Frequency subsystem.
- C.
Tropospheric scatter modem.
- D.
Transmitter-amplifier converter.
Correct Answer
C. Tropospheric scatter modem.Explanation
The rubidium standard is a highly accurate and stable clock source used for precise timing and synchronization in communication systems. In the AN/TRC-170 terminal, the rubidium standard is contained within the tropospheric scatter modem unit. This unit is responsible for transmitting and receiving signals over long distances via tropospheric scatter communication, and it utilizes the rubidium standard to ensure accurate timing and synchronization of these signals.Rate this question:
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- 9.
The quick reaction antenna for the V3 AN/TRC–170 terminal uses how many linearly dualpolarized antennas?
- A.
Two 6-foot-diameter.
- B.
Four 6-foot-diameter.
- C.
Two 9.5-foot-diameter.
- D.
Four 9.5-foot-diameter.
Correct Answer
A. Two 6-foot-diameter.Explanation
The quick reaction antenna for the V3 AN/TRC-170 terminal uses two 6-foot-diameter linearly dual-polarized antennas.Rate this question:
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- 10.
The Tropo/Satellite Support Radio frequency coverage extends from
- A.
4.4 to 5.25 GHz.
- B.
7.25 to 8.4 GHz.
- C.
14.4 to 15.25 GHz.
- D.
17.25 to 18.4 GHz.
Correct Answer
C. 14.4 to 15.25 GHz.Explanation
The correct answer is 14.4 to 15.25 GHz. This range falls within the frequency coverage of Tropo/Satellite Support Radio.Rate this question:
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- 11.
Which maximum distance in miles can a Tropo/Satellite Support Radio operate with the 2- foot antenna?
- A.
9.
- B.
24.
- C.
90.
- D.
240.
Correct Answer
B. 24.Explanation
A Tropo/Satellite Support Radio with a 2-foot antenna can operate at a maximum distance of 24 miles. This means that the radio can transmit and receive signals within a radius of 24 miles, allowing for communication over long distances. The larger the antenna, the greater the range of the radio, so a 2-foot antenna limits the operating distance to 24 miles.Rate this question:
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- 12.
What is the maximum distance in feet the Tropo/Satellite Support Radio’s radio frequency and baseband assemblies can be separated?
- A.
50.
- B.
100.
- C.
150.
- D.
200.
Correct Answer
C. 150.Explanation
The maximum distance in feet that the Tropo/Satellite Support Radio's radio frequency and baseband assemblies can be separated is 150.Rate this question:
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- 13.
In the Tropo/Satellite Support Radio’s baseband assembly, a 1-volt peak-to-peak input signal results in how much frequency deviation in the transmitter?
- A.
±4 MHz.
- B.
Less than ±4 MHz.
- C.
More than ±4 MHz.
- D.
No signal deviation.
Correct Answer
A. ±4 MHz.Explanation
A 1-volt peak-to-peak input signal in the Tropo/Satellite Support Radio's baseband assembly results in a frequency deviation of ±4 MHz in the transmitter.Rate this question:
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- 14.
Which frequency is the intermediate frequency of the Tropo/Satellite Support Radio?
- A.
70 MHz with a 10 MHz bandpass.
- B.
70 MHz with a 20 MHz bandpass.
- C.
700 MHz with a 10 MHz bandpass.
- D.
700 MHz with a 20 MHz bandpass.
Correct Answer
B. 70 MHz with a 20 MHz bandpass.Explanation
The intermediate frequency (IF) of the Tropo/Satellite Support Radio is 70 MHz with a 20 MHz bandpass. This means that the radio uses a frequency of 70 MHz as the intermediate frequency and has a bandpass of 20 MHz, which allows for a range of frequencies within that bandwidth to pass through. This specific combination of IF and bandpass is used in the Tropo/Satellite Support Radio.Rate this question:
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- 15.
What is the inclination angle of a polar orbit?
- A.
0°.
- B.
45°.
- C.
90°.
- D.
180°.
Correct Answer
C. 90°.Explanation
The inclination angle of a polar orbit is 90°. A polar orbit is a type of orbit where the satellite passes over or near the Earth's poles on each revolution. In this type of orbit, the satellite's path is perpendicular to the equator, resulting in an inclination angle of 90°. This allows the satellite to cover the entire globe and pass over all latitudes.Rate this question:
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- 16.
What is the procedure called when keeping a satellite in a desired position, in orbit and within acceptable limits?
- A.
Shift.
- B.
Period.
- C.
Air drag.
- D.
Station keeping.
Correct Answer
D. Station keeping.Explanation
Station keeping refers to the procedure of maintaining a satellite in a desired position within its orbit and ensuring it stays within acceptable limits. This involves making adjustments to the satellite's trajectory and velocity to counteract the effects of gravitational forces, atmospheric drag, and other factors that can cause the satellite to drift off course. Station keeping is crucial for satellites that provide services such as communication, weather monitoring, and navigation, as it ensures their continuous coverage and functionality.Rate this question:
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- 17.
Which satellite reflects signals transmitted toward it?
- A.
Active.
- B.
Delay.
- C.
Passive.
- D.
Real-time.
Correct Answer
C. Passive.Explanation
Passive satellites reflect signals transmitted toward them. Unlike active satellites, which generate and transmit their own signals, passive satellites simply reflect or bounce back signals that are transmitted from the ground. These satellites are commonly used for communication purposes, such as in satellite television or radio, where signals are transmitted from Earth to the satellite and then reflected back to a receiving station.Rate this question:
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- 18.
An advantage of passive satellites is that they
- A.
Have a larger transmitter power.
- B.
Have a larger antenna system.
- C.
Have more sensitive equipment.
- D.
Operate over a wider-frequency range.
Correct Answer
D. Operate over a wider-frequency range.Explanation
Passive satellites operate over a wider-frequency range. This means that they are capable of receiving and transmitting signals across a broader spectrum of frequencies. This advantage allows passive satellites to be more versatile and adaptable in their communication capabilities, as they can handle a wider variety of signals and frequencies. This flexibility is crucial in various applications, such as telecommunications, remote sensing, and scientific research, where different frequency bands may be required for different purposes.Rate this question:
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- 19.
What is the seconds delay of a real-time satellite?
- A.
0.1.
- B.
0.6.
- C.
1.0.
- D.
6.0.
Correct Answer
B. 0.6.Explanation
The correct answer is 0.6. This suggests that the real-time satellite has a delay of 0.6 seconds. This delay refers to the time it takes for the satellite to transmit data or signals from one point to another. It indicates that there is a slight delay in the communication process due to the distance the signals have to travel.Rate this question:
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- 20.
Which satellite access technique was the first multiple access method developed?
- A.
Code division multiple access (CDMA).
- B.
Time division multiple access (TDMA).
- C.
Demand assigned multiple access (DAMA).
- D.
Frequency division multiple access (FDMA).
Correct Answer
D. Frequency division multiple access (FDMA).Explanation
Frequency division multiple access (FDMA) was the first multiple access method developed. In FDMA, different users are assigned different frequency bands to transmit their signals simultaneously. Each user is allocated a specific frequency range, and the signals are separated by using different carrier frequencies. This allows multiple users to share the same physical channel without interfering with each other. FDMA is commonly used in analog cellular systems and satellite communication systems.Rate this question:
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- 21.
Which satellite access technique is being used when all channels are pooled and used by any station, according to its instantaneous traffic load?
- A.
Code division multiple access (CDMA).
- B.
Time division multiple access (TDMA).
- C.
Demand assigned multiple access (DAMA).
- D.
Frequency division multiple access (FDMA).
Correct Answer
C. Demand assigned multiple access (DAMA).Explanation
Demand assigned multiple access (DAMA) is the satellite access technique being used when all channels are pooled and used by any station, according to its instantaneous traffic load. DAMA allows stations to dynamically request and assign channels as needed, based on their traffic demands. This ensures efficient utilization of satellite resources and allows for flexible allocation of channels among multiple stations. CDMA, TDMA, and FDMA are not suitable for this scenario as they involve different methods of channel allocation.Rate this question:
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- 22.
To calculate look angles (e.g. antenna azimuth and elevation) from the ground terminal to the satellite, you need to know the terminal’s latitude and longitude, as well as the satellite’s latitude, longitude, and
- A.
Velocity.
- B.
Height.
- C.
Speed.
- D.
Depth.
Correct Answer
B. Height.Explanation
To calculate look angles from the ground terminal to the satellite, you need to know the terminal's latitude and longitude, as well as the satellite's latitude, longitude, and height. The height of the satellite is an important factor in determining the correct azimuth and elevation angles. Without knowing the height of the satellite, it would be impossible to accurately calculate the look angles. The other options, such as velocity, speed, and depth, are not relevant in this context and would not affect the calculation of look angles.Rate this question:
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- 23.
When computing satellite look angles, the ground distance on the earth’s surface is expressed in
- A.
Degrees.
- B.
Seconds.
- C.
Minutes.
- D.
Nautical miles.
Correct Answer
A. Degrees.Explanation
When computing satellite look angles, the ground distance on the earth's surface is expressed in degrees. This is because look angles are used to determine the direction of the satellite from a specific point on the earth's surface. The ground distance is measured in degrees of latitude and longitude, which provide a precise and standardized way to describe locations on the earth's surface. Using degrees allows for accurate calculations and consistent communication of satellite positions.Rate this question:
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- 24.
What does one degree of arc on the Earth’s surface equal?
- A.
One statute mile.
- B.
One nautical mile.
- C.
69 statute miles.
- D.
69 nautical miles.
Correct Answer
C. 69 statute miles.Explanation
One degree of arc on the Earth's surface equals approximately 69 statute miles. This measurement is derived from the Earth's circumference, which is approximately 24,901 miles. Dividing the circumference by 360 (representing the degrees in a circle) gives us the value of 69.17 miles per degree of arc. However, since the answer options are rounded, the closest approximation is 69 statute miles.Rate this question:
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- 25.
Solar time is based on
- A.
Atomic clock oscillations.
- B.
Apparent constellation movement.
- C.
The moon’s rotation about the sun.
- D.
The apparent motion of the sun in the sky.
Correct Answer
D. The apparent motion of the sun in the sky.Explanation
Solar time is based on the apparent motion of the sun in the sky. Solar time is determined by the position of the sun in relation to a specific location on Earth. As the Earth rotates on its axis, the sun appears to move across the sky, causing shadows to shift. Solar time is calculated based on this apparent motion of the sun, with each day divided into 24 hours based on the sun's position at noon. This method of timekeeping is different from atomic clock oscillations, the moon's rotation about the sun, or apparent constellation movement.Rate this question:
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- 26.
An atomic time scale could be based on the frequency of what type of oscillator?
- A.
Pendulum.
- B.
Crystal.
- C.
Quartz.
- D.
Cesium.
Correct Answer
D. Cesium.Explanation
An atomic time scale could be based on the frequency of a cesium oscillator. Cesium atomic clocks are the most accurate and reliable timekeeping devices available. They work by measuring the vibrations of cesium atoms, which have a very stable and precise resonant frequency. This frequency is used as the basis for defining the second in the International System of Units (SI). By using cesium oscillators, atomic time scales can be established with extremely high accuracy and stability. Pendulums, crystals, and quartz are not suitable for creating atomic time scales as they do not have the same level of precision and stability as cesium.Rate this question:
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- 27.
What kind of clock system is coordinated universal time (UTC) based?
- A.
12-hour.
- B.
24-hour.
- C.
Daylight saving.
- D.
Amplitude modulation and pulse modulation.
Correct Answer
B. 24-hour.Explanation
The correct answer is 24-hour. Coordinated Universal Time (UTC) is based on a 24-hour clock system. This means that the time is divided into 24 equal parts, with each part representing one hour. This system is used worldwide to ensure consistency and standardization in timekeeping across different time zones. Unlike the 12-hour clock system, which repeats after 12 hours, the 24-hour clock system continues counting up to 24 hours before starting over. This allows for a more precise and efficient way of representing time.Rate this question:
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- 28.
A number of organizations can maintain accurate time-of-day clocks by referencing a standard time interval of one
- A.
Second.
- B.
Minute.
- C.
Hour.
- D.
Day.
Correct Answer
A. Second.Explanation
Organizations can maintain accurate time-of-day clocks by referencing a standard time interval of one second. This is because a second is the smallest unit of time that can be measured accurately and precisely. By synchronizing their clocks to this standard, organizations can ensure that their timekeeping is consistent and reliable. Additionally, using a second as the standard time interval allows for easier coordination and communication between different organizations and systems that rely on accurate timekeeping.Rate this question:
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- 29.
The agency responsible for coordinated universal time (UTC) is the
- A.
United States Naval Observatory (USNO).
- B.
International Bureau of Weights and Measures (BIPM).
- C.
Precision Measurement Equipment Laboratory (PMEL).
- D.
National Institute of Standards and Technology (NIST).
Correct Answer
B. International Bureau of Weights and Measures (BIPM).Explanation
The International Bureau of Weights and Measures (BIPM) is responsible for coordinating Universal Time Coordinated (UTC). UTC is the primary time standard used worldwide for civil timekeeping, ensuring that time is consistent and accurate across different locations. The BIPM, based in France, is an international organization that maintains the International System of Units (SI) and oversees the measurement standards used globally. It collaborates with various national timekeeping agencies to ensure the accuracy and synchronization of UTC. The United States Naval Observatory (USNO), Precision Measurement Equipment Laboratory (PMEL), and National Institute of Standards and Technology (NIST) are all involved in timekeeping and standards, but the BIPM is specifically responsible for UTC coordination.Rate this question:
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- 30.
Uploading satellite control data, tracking missiles, and predicting satellite tracking coordinates are examples of missions where all parties involved must have
- A.
Offset timing.
- B.
Synchronized timing.
- C.
Identical time code formats.
- D.
Different time code formats.
Correct Answer
B. Synchronized timing.Explanation
In missions such as uploading satellite control data, tracking missiles, and predicting satellite tracking coordinates, it is crucial for all parties involved to have synchronized timing. This means that all systems and devices need to be aligned and operating on the same time frame to ensure accurate and coordinated actions. Having synchronized timing allows for efficient communication, coordination, and execution of tasks, ultimately leading to successful mission outcomes.Rate this question:
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- 31.
When any frequency source regardless of its accuracy or stability is used as the sole calibration reference for other frequency sources, what kind of standard is it?
- A.
First generation.
- B.
Secondary.
- C.
Primary.
- D.
Class I.
Correct Answer
C. Primary.Explanation
When any frequency source is used as the sole calibration reference for other frequency sources, it is considered a primary standard. A primary standard is a highly accurate and stable reference that is used to calibrate and validate other instruments or standards. It is the highest level of standard in terms of accuracy and reliability, and it is typically traceable to national or international standards organizations.Rate this question:
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- 32.
What two factors cause a quartz oscillator’s resonant frequency to drift?
- A.
Humidity and aging.
- B.
Temperature and aging.
- C.
Humidity and operating frequency.
- D.
Temperature and operating frequency.
Correct Answer
B. Temperature and aging.Explanation
A quartz oscillator's resonant frequency can drift due to temperature changes and aging. Temperature affects the quartz crystal's physical properties, causing its resonant frequency to change. Aging refers to the gradual degradation of the crystal over time, leading to a shift in its resonant frequency. Humidity and operating frequency do not directly cause the drift in the resonant frequency of a quartz oscillator.Rate this question:
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- 33.
The operation of the atomic clock is based on the phenomenon that
- A.
Crystals resonate when an electric charge is applied.
- B.
Atoms release energy at a particular resonant frequency.
- C.
Atoms are sensitive to temperature and directional effects.
- D.
When atoms are split they produce predictable nuclear reactions.
Correct Answer
B. Atoms release energy at a particular resonant frequency.Explanation
The correct answer is "atoms release energy at a particular resonant frequency." Atomic clocks work by measuring the vibrations of atoms, particularly the oscillations of electrons within the atom. These oscillations occur at a specific frequency, known as the resonant frequency. By measuring these vibrations, atomic clocks can accurately keep time.Rate this question:
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- 34.
To send information over telephone lines, the modulator in a voice modem converts the
- A.
Audio signal into digital data.
- B.
Optical signal into digital data.
- C.
Digital data into an audio signal.
- D.
Digital data into an optical signal.
Correct Answer
C. Digital data into an audio signal.Explanation
The modulator in a voice modem is responsible for converting the digital data into an audio signal. This audio signal is then transmitted over telephone lines.Rate this question:
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- 35.
What is multiplexing?
- A.
Transmitting one signal over multiple transmission paths.
- B.
Transmitting one signal multiple times over a single transmission path.
- C.
Combining multiple signals for transmission over a single transmission path.
- D.
Combining multiple signals for transmission over separate, individual transmission paths.
Correct Answer
C. Combining multiple signals for transmission over a single transmission path.Explanation
Multiplexing refers to the process of combining multiple signals into a single transmission path. This allows for more efficient use of the available bandwidth. Instead of using separate transmission paths for each signal, multiplexing enables multiple signals to be transmitted simultaneously over a single path. This can be achieved using various techniques such as time-division multiplexing (TDM) or frequency-division multiplexing (FDM). By combining multiple signals, multiplexing enables increased data transmission capacity and improved efficiency in communication systems.Rate this question:
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- 36.
Which division technique of multiplexing, samples each low speed channel in sequence to interleave bits or characters, and then transmit them at high speed?
- A.
Wavelength.
- B.
Frequency.
- C.
Code.
- D.
Time.
Correct Answer
D. Time.Explanation
Time division multiplexing (TDM) is a division technique of multiplexing that samples each low-speed channel in sequence to interleave bits or characters and then transmits them at high speed. In TDM, each channel is allocated a specific time slot within a predefined time frame, allowing multiple channels to share the same transmission medium. This enables efficient utilization of the available bandwidth and ensures that each channel gets its turn to transmit data. Therefore, the correct answer is Time.Rate this question:
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- 37.
What specifically does wavelength division multiplexing assign each incoming optical signal?
- A.
Pseudorandom code.
- B.
Frequency of light.
- C.
Radio frequency.
- D.
Time slot.
Correct Answer
B. Frequency of light.Explanation
Wavelength division multiplexing assigns each incoming optical signal a specific frequency of light. This means that different signals can be transmitted simultaneously over a single optical fiber by using different wavelengths of light. By assigning different frequencies to each signal, they can be separated and then combined again at the receiving end. This allows for efficient and high-capacity transmission of multiple signals over a single fiber.Rate this question:
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- 38.
What comprises a telemetry data stream?
- A.
Mission data, mission satellite health, and status data.
- B.
Command data, mission satellite health, and status data.
- C.
Mission data, satellite ephemeris table, and satellite status data.
- D.
Command data, satellite ephemeris table, and satellite status data.
Correct Answer
A. Mission data, mission satellite health, and status data.Explanation
A telemetry data stream is composed of mission data, mission satellite health, and status data. This means that the stream includes information about the mission objectives and goals, as well as the overall health and status of the satellite involved in the mission. By monitoring and analyzing this data, scientists and engineers can gather important insights into the progress and performance of the mission, allowing them to make informed decisions and adjustments as necessary.Rate this question:
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- 39.
Stability is important to a satellite in the space environment. What does stability allow that makes it so important?
- A.
Payload to operate accurately and the satellite bus to receive commands and upload data reliably.
- B.
Payload to operate accurately and the satellite bus to receive uploaded inertial reference and data reliably.
- C.
Accelerometers to operate accurately and the satellite bus to receive commands and upload data reliably.
- D.
Accelerometers to operate accurately and the satellite bus to receive uploaded inertial reference and data reliably.
Correct Answer
A. Payload to operate accurately and the satellite bus to receive commands and upload data reliably.Explanation
Stability is important to a satellite in the space environment because it allows the payload to operate accurately and the satellite bus to receive commands and upload data reliably. A stable satellite ensures that the payload, which could be scientific instruments or communication equipment, functions properly and provides accurate data. Additionally, stability ensures that the satellite bus, which controls the satellite's operations and communication, can effectively receive commands from the ground station and upload data back to Earth without any errors or interruptions.Rate this question:
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- 40.
On a satellite, position, and orientation control is especially critical for which type of antenna?
- A.
Broadband.
- B.
Wide angle.
- C.
High frequency.
- D.
Highly directional.
Correct Answer
D. Highly directional.Explanation
Position and orientation control is especially critical for highly directional antennas because these antennas are designed to transmit and receive signals in a specific direction with a narrow beamwidth. Any deviation in the position or orientation of the antenna can result in a loss of signal strength or even complete signal failure. Therefore, precise control is necessary to ensure that the highly directional antenna is correctly aligned and pointed towards the desired target.Rate this question:
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- 41.
The purpose of satellite antenna pointing data is to
- A.
Update the mission satellite orbital database and ephemeris table.
- B.
Update the mission satellite orbital database and satellite acquisition timing.
- C.
Direct the servo positioning equipment to drive motors that position the antenna to specific acquisition angles.
- D.
Direct the servo positioning equipment to position the antenna to specific acquisition angles, and command the ground equipment to execute autotracking.
Correct Answer
C. Direct the servo positioning equipment to drive motors that position the antenna to specific acquisition angles.Explanation
The purpose of satellite antenna pointing data is to direct the servo positioning equipment to drive motors that position the antenna to specific acquisition angles. This means that the antenna needs to be accurately directed towards a specific angle in order to acquire the satellite signal. The servo positioning equipment is responsible for controlling the motors that physically move the antenna to the desired angles. Therefore, the pointing data is used to provide the necessary instructions to the servo positioning equipment, ensuring that the antenna is properly aligned for satellite acquisition.Rate this question:
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- 42.
This type of command, sent to the satellite by the space systems mission control complex, contains embedded timing that specifies the time the satellite will execute the command.
- A.
Real-time.
- B.
Time-delayed.
- C.
Timed program.
- D.
Stored program.
Correct Answer
D. Stored program.Explanation
A stored program is the correct answer because it refers to a command that is stored in the satellite's system and executed at a specified time. This means that the command is not sent in real-time but is instead programmed in advance with embedded timing. The other options, such as real-time or time-delayed, do not accurately describe the nature of the command as specified in the question.Rate this question:
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- 43.
What is the purpose of the space system user segment?
- A.
Receive, process, use, or distribute mission data as required by a program’s tasking.
- B.
Receive, process, use, or distribute payload data and provide essential space support tasks as required by a program’s tasking.
- C.
Transmit, process, use, or distribute mission data as required by a program’s tasking.
- D.
Transmit, process, use, or distribute payload data and provide essential space support tasks as required by a program’s tasking.
Correct Answer
A. Receive, process, use, or distribute mission data as required by a program’s tasking.Explanation
The purpose of the space system user segment is to receive, process, use, or distribute mission data as required by a program's tasking. This means that the user segment is responsible for handling and managing the data related to the program's mission. It may involve receiving data from other segments, processing it, using it for various purposes, and distributing it as needed. The user segment plays a crucial role in ensuring that the mission data is utilized effectively and efficiently to achieve the program's objectives.Rate this question:
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- 44.
The two major subdivisions of the Defense Meteorological Satellite Program (DMSP) user segment are
- A.
Air Force Weather Agency and the Fleet Numerical Meteorology Oceanography Center and tactical terminals.
- B.
Air Force Weather Agency and Fleet Numerical Meteorology Oceanography Center only.
- C.
Air Force Weather Agency and National Oceanographic Atmospheric Administration.
- D.
Fleet Numerical Meteorology Oceanography Center and National Oceanographic Atmospheric Administration and tactical terminals.
Correct Answer
A. Air Force Weather Agency and the Fleet Numerical Meteorology Oceanography Center and tactical terminals.Explanation
The correct answer is Air Force Weather Agency and the Fleet Numerical Meteorology Oceanography Center and tactical terminals. This answer is correct because it includes both major subdivisions of the Defense Meteorological Satellite Program (DMSP) user segment, which are the Air Force Weather Agency and the Fleet Numerical Meteorology Oceanography Center. Additionally, it mentions the inclusion of tactical terminals, which are also part of the user segment.Rate this question:
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- 45.
Which early warning center receives Defense Support Program warning data from the 460th Space Wing units?
- A.
Air Force Weather Agency.
- B.
Mission Control Squadron.
- C.
Mission Control Command.
- D.
North American Aerospace Defense Command.
Correct Answer
D. North American Aerospace Defense Command.Explanation
The North American Aerospace Defense Command (NORAD) receives Defense Support Program warning data from the 460th Space Wing units. NORAD is responsible for aerospace warning and control, and it collaborates with the United States Space Command to provide early warning of missile launches and other space-related activities.Rate this question:
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- 46.
What system supports the National Command Authority and provides all-service (Army, Navy and Air Force) communication for interoperable command, control, and communications (C3) at all levels of conflict?
- A.
Defense Support Program.
- B.
Global Positioning System.
- C.
Military Strategic and Tactical Relay.
- D.
Defense Satellite Communications System.
Correct Answer
C. Military Strategic and Tactical Relay.Explanation
The Military Strategic and Tactical Relay system supports the National Command Authority and provides communication for interoperable command, control, and communications at all levels of conflict. This system is designed to facilitate communication between the Army, Navy, and Air Force, ensuring effective coordination and decision-making in various conflict scenarios. The Defense Support Program, Global Positioning System, and Defense Satellite Communications System may have other functions, but they do not specifically support the National Command Authority and all-service communication for interoperable C3.Rate this question:
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- 47.
Telemetry refers to
- A.
A low power signal transmitted from the satellite and is separate from the communications components.
- B.
A low power signal transmitted from the satellite and is part of the communications components.
- C.
The data transmitted by the satellite concerning on-board status and is separate from the communications components.
- D.
The data transmitted by the satellite concerning on-board status and is part of the communications components.
Correct Answer
C. The data transmitted by the satellite concerning on-board status and is separate from the communications components.Explanation
Telemetry refers to the data transmitted by the satellite concerning on-board status and is separate from the communications components. This means that telemetry is a separate signal from the satellite that carries information about the satellite's status, such as its location, temperature, and other relevant data. It is not part of the communications components, which are responsible for transmitting messages and data to and from the satellite.Rate this question:
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- 48.
Automatic tracking systems are superior to programmed tracking systems because they
- A.
Use servomechanisms to control antenna movements.
- B.
Track only signals received from the satellite.
- C.
Track the actual position of the satellite.
- D.
Use updated ephemeris data.
Correct Answer
B. Track only signals received from the satellite.Explanation
Automatic tracking systems are superior to programmed tracking systems because they track only signals received from the satellite. This means that they are able to precisely follow the movements and position of the satellite in real-time, ensuring accurate tracking. Programmed tracking systems, on the other hand, may rely on pre-determined instructions or algorithms, which may not always account for changes in the satellite's position or movement. By tracking only signals received from the satellite, automatic tracking systems can provide more reliable and up-to-date information.Rate this question:
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- 49.
What signal originating from the satellite do we use to acquire and track the satellite?
- A.
Beacon.
- B.
Ephemeris.
- C.
Telemetry.
- D.
Communication.
Correct Answer
A. Beacon.Explanation
The signal originating from the satellite that we use to acquire and track the satellite is called the beacon. The beacon is a specific type of signal that is transmitted by the satellite and can be received by ground stations. It is used to establish a connection with the satellite and track its movements and position. The beacon signal provides important information about the satellite's location, velocity, and timing, which is crucial for accurate tracking and communication with the satellite.Rate this question:
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- 50.
The intermediate frequencies/levels used by Defense Satellite Communications System (DSCS) earth terminals are 70 MHz at
- A.
–10 dBm and 630 MHz @ –13 dBm.
- B.
–13 dBm and 630 MHz @ –10 dBm.
- C.
–10 dBm and 700 MHz @ –13 dBm.
- D.
–13 dBm and 700 MHz @ –10 dBm.
Correct Answer
C. –10 dBm and 700 MHz @ –13 dBm.Explanation
The correct answer is –10 dBm and 700 MHz @ –13 dBm. This is because the question is asking for the intermediate frequencies/levels used by the Defense Satellite Communications System (DSCS) earth terminals. The given answer specifies that the intermediate frequency is 700 MHz and the level is –13 dBm. The other options either have the incorrect frequency or level values.Rate this question:
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Quiz Review Timeline +
Our quizzes are rigorously reviewed, monitored and continuously updated by our expert board to maintain accuracy, relevance, and timeliness.
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Current Version
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Mar 20, 2023Quiz Edited by
ProProfs Editorial Team -
Jun 16, 2013Quiz Created by
Mmikhaylevskiy
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