Z3D153 Ure Vol 3(Air Force )

Active and passive are the two types of communication satellites. Active satellites have onboard equipment to amplify and retransmit signals, allowing for long-distance communication. They actively participate in the transmission process. On the other hand, passive satellites reflect or redirect signals without amplification. They simply bounce the signals back to Earth, allowing for communication over a larger area.

Coordinated Universal Time (UTC) is based on a 24-hour clock system. This means that the day is divided into 24 equal parts, with each part representing one hour. This system is used worldwide to ensure that time is standardized and coordinated across different time zones. Unlike the 12-hour clock system, which repeats after 12 hours, the 24-hour clock system allows for a continuous and unambiguous representation of time throughout the day. Therefore, UTC, being an international time standard, follows the 24-hour clock system.

Organizations can maintain accurate time-of-day clocks by referencing a standard time interval of one second. A second is the smallest unit of time and is widely accepted as the standard for measuring time intervals. By synchronizing their clocks with this standard, organizations can ensure accuracy and consistency in timekeeping.

The Inmarsat headquarters is located in London, England.

The correct answer is Defense Information Systems Agency (DISA). DISA is responsible for issuing telecommunications service orders. The Department of Defense (DOD) is a larger organization within which DISA operates. The user's technical control facility is responsible for managing and controlling the technical aspects of the user's telecommunications systems. The National Communications System (NCS) is a former organization that was responsible for national security and emergency preparedness telecommunications.

The signal originating from the satellite that we use to acquire and track the satellite is called the beacon. The beacon signal is transmitted by the satellite and is received by ground stations to determine the satellite's position, track its movement, and acquire a stable connection. It provides essential information for satellite tracking and communication purposes.

Satellite access authorization is a method provided by satellite communication SATCOM planners. This method involves granting permission and authorization to access the satellite for communication purposes. It ensures that only authorized users are allowed to use the satellite resources, maintaining security and efficient utilization of the satellite system. The other options mentioned, such as programmed ground terminal, computer-based application, and satellite slide rule, do not specifically relate to the process of authorizing satellite access.

Conflicts regarding Defense Satellite Communications System (DSCS) ground mobile forces (GMF) satellite resources that cannot be settled by the Defense Information Systems Agency (DISA) and the regional satellite communications support center (RSSC) are resolved by the Joint Staff. The Joint Staff is responsible for providing advice and support to the Chairman of the Joint Chiefs of Staff and the Combatant Commanders. They have the authority to make decisions and resolve conflicts between different military organizations. In this case, since DISA and RSSC were unable to settle the conflict, the Joint Staff would step in to make the final decision and resolve the issue.

The resonant frequency of a quartz oscillator can drift due to two factors: temperature and aging. Temperature changes can cause the quartz crystal to expand or contract, leading to a shift in its resonant frequency. Aging refers to the gradual degradation of the quartz crystal over time, which can also cause a drift in the resonant frequency. Humidity and operating frequency are not directly responsible for the drift in the resonant frequency of a quartz oscillator.

The highest priority mission of the Defense Support Program (DSP) is the North American warning. This means that the DSP is primarily focused on detecting and providing early warning of any potential threats to North America, such as missile launches or other attacks. This mission is crucial for the defense and security of the continent, making it the top priority for the DSP.

The International Bureau of Weights and Measures (BIPM) is responsible for coordinating Universal Time Coordinated (UTC). UTC is a time standard used worldwide to ensure accurate timekeeping across different countries and time zones. BIPM is an international organization that maintains and develops the International System of Units (SI), including the measurement of time. They work closely with national metrology institutes, including the United States Naval Observatory (USNO) and the National Institute of Standards and Technology (NIST), to ensure the accuracy and consistency of UTC. Therefore, BIPM is the correct answer for the agency responsible for UTC.

The correct answer is Iridium. Iridium is not included in INMARSAT mobile satellite services (MSS). INMARSAT provides services such as Swift broadband, Fleet broadband (maritime), and Broadband Global Area Network (BGAN), but Iridium is not part of their services.

XTAR is the correct answer because it is a satellite company that is specifically designed to interface with all current X-band terminals. X-band is a frequency range used for satellite communications, and XTAR specializes in providing satellite services in this frequency range. Inmarsat, INTELSAT, and EUTELSAT are also satellite companies, but they may not necessarily be designed to interface with all current X-band terminals.

The major axis is the correct answer because it refers to the longest distance across an elliptical orbit. In an ellipse, the major axis is the line that extends from one end of the ellipse to the other, passing through the center. It represents the longest distance between any two points on the elliptical orbit. The minor axis, on the other hand, represents the shortest distance across the ellipse. Apogee and perigee, on the other hand, refer to the points in an orbit where the object is farthest and closest to the body it is orbiting, respectively.

The inclination angle of a polar orbit is 90 degrees. A polar orbit is an orbit that passes over or near the Earth's poles, allowing the satellite to cover the entire Earth's surface. In a polar orbit, the satellite's path is perpendicular to the equator, meaning it crosses the equator at a 90-degree angle. This allows the satellite to provide global coverage and is commonly used for Earth observation and mapping satellites.

Passive satellites reflect signals transmitted toward them. Unlike active satellites that generate and transmit their own signals, passive satellites simply reflect or bounce back signals that are sent to them. These satellites are commonly used for communication purposes, such as in satellite TV and radio systems, where the signals are sent from the ground stations to the satellite and then redirected back to Earth.

Astronomical time is based on the apparent motion of the sun in the sky. This is because the sun appears to rise in the east and set in the west due to the rotation of the Earth. This daily cycle of the sun's apparent motion is used as the basis for measuring time.

The Air Force Satellite Control Network (AFSCN) command and control nodes are the Environmental Satellite Operations Center at Schriever AFB, CO, and the National Oceanographic and Atmospheric Administration (NOAA) Satellite Operations Control Center at Suitland, MD.

The MARK IVB antennas can be located up to 1500 feet away from the processing area.

Demand assigned multiple access (DAMA) is the correct answer because it is a satellite access technique where all channels are pooled and used by any station based on its instantaneous traffic load. In DAMA, channels are dynamically assigned to stations as per their demand, allowing efficient utilization of satellite resources. This technique ensures that each station gets the required bandwidth when needed, optimizing the overall system capacity. CDMA, TDMA, and FDMA are not applicable in this scenario as they do not involve dynamic allocation of channels based on traffic load.

Coordinated Universal Time (UTC) is a time scale that provides a universally agreed standard time with the stability and accuracy of atomic time. It is synchronized with the Earth's motion about the sun and is widely used as a reference for timekeeping across the globe. UTC ensures that time remains consistent and reliable, making it a dependable choice for various applications such as international communication, global navigation systems, and scientific research.

The correct answer is that atoms release energy at a particular resonant frequency. This is the basis for the operation of an atomic clock. Atomic clocks use the oscillations of atoms to measure time with extreme accuracy. When atoms are excited, they release energy in the form of electromagnetic radiation at a specific frequency. By measuring this frequency, the atomic clock can accurately determine the passage of time.

The correct answer is "meridian". To determine the number of hours coordinated universal time (UTC) differs from your local time, you must determine the number of time zones between your location and the location of the meridian. The meridian, also known as the prime meridian, is the line of longitude that passes through the Royal Observatory in Greenwich, London. It is used as a reference point for measuring time zones and determining the offset from UTC. By calculating the number of time zones between your location and the meridian, you can determine the time difference between UTC and your local time.

Forward error correction (FEC) is a technique used in communication systems to improve the reliability of data transmission. It relies on the transmitter sending multiple copies of the same message to the distant end using a predetermined algorithm. This algorithm adds redundant information to the transmitted data, which allows the receiver to detect and correct errors that may occur during transmission. By sending multiple copies and using error correction algorithms, FEC ensures that the receiver can recover the original message even if some of the transmitted data is corrupted or lost. Controlled diphase, non-return to zero, and quadrature phase shift keying (QPSK) are different modulation techniques used in communication systems, but they do not rely on transmitting multiple copies of the same message for error correction.

The tropo/satellite support radio frequency range is 14.4 to 15.25 GHz. This range is commonly used for long-distance communication through the troposphere and for satellite communications. It provides a good balance between signal strength and atmospheric interference, making it suitable for reliable communication over large distances.

Iridium is the correct answer because it is a commercial satellite communication system that can offer true pole-to-pole global coverage. Unlike the other options, Iridium's network of satellites is designed to provide seamless coverage across the entire globe, including the poles. This makes it an ideal choice for industries and users who require communication capabilities in remote and extreme locations.

The satellite readout station equipment group consists of three types of equipment: radio frequency set, transmit/receiver set, and digital equipment set. These three types of equipment are necessary for the satellite readout station to receive and process signals from the satellite. The radio frequency set is responsible for receiving and converting the satellite signals into a usable form. The transmit/receiver set allows for the transmission of signals back to the satellite if necessary. Finally, the digital equipment set processes and analyzes the received signals. Therefore, the correct answer is the set that includes all three types of equipment.

The correct answer is spot beam. A spot beam antenna is able to provide high gain and selective coverage of any ground station visible within its own footprint on the earth's surface. This means that it can focus its signal on a specific area, allowing for more efficient and targeted communication.

The function of the telecommunication certification office is to ensure that the user agency is prepared to pay for the service. This implies that the office verifies the financial readiness of the agency before providing the requested telecommunications service.

The demodulator module is responsible for removing the intelligence from the intermediate frequency signal. It extracts the original information or data from the modulated carrier signal, allowing it to be processed and understood by the receiving device. The low noise amplifier amplifies the weak incoming signal, the down converter converts the high-frequency signal to a lower intermediate frequency, and the up converter converts the intermediate frequency to a higher frequency for transmission. However, none of these modules specifically strip away the intelligence from the intermediate frequency like the demodulator does.

When the same frequency radiates simultaneously in two different planes, it refers to the concept of polarization. Polarization is a property of electromagnetic waves that describes the orientation of the electric field vector. In this case, the wave is radiating in two different planes simultaneously, indicating that it has different polarizations in each plane. Therefore, the correct answer is polarization.

Handheld satellite phone communications are not normally provided through commercial wideband services. Wideband services typically refer to high-capacity communication networks that offer services such as video teleconferencing, V-SAT networks, and high-speed internet connectivity. Handheld satellite phones, on the other hand, rely on satellite technology for communication and are not typically included in commercial wideband services.

Multiplexing refers to the process of combining multiple information channels onto a common transmission medium. This allows for the efficient utilization of the available bandwidth by transmitting multiple signals simultaneously. By multiplexing, different signals can be transmitted over a single transmission path, which reduces the need for separate transmission paths for each signal. This technique is widely used in telecommunications and networking to optimize the use of resources and increase the capacity of the transmission medium.

Polarization diversity requires two antennas, two receivers, and two transmitters. This is because polarization refers to the orientation of the electromagnetic waves, and by using two antennas with different polarization orientations, it allows for better signal reception and transmission in environments with varying polarization. Having two receivers and transmitters ensures that the signals can be properly received and transmitted using the respective polarizations.

The number of Global Positioning System (GPS) orbital planes is 6. The GPS consists of a constellation of satellites that orbit the Earth. These satellites are distributed among six orbital planes, with each plane containing multiple satellites. This configuration ensures that there are always enough satellites in view from any point on the Earth's surface, allowing for accurate positioning and navigation.

Each UHF Follow-on satellite has a total of 39 ultrahigh frequencies (UHF) channels available.

Solid state power amplifiers use semiconductor transistors designed for microwave and higher frequency RF operation. Klystron amplifiers use vacuum tubes, traveling wave tube amplifiers use electron beams, and metal oxide field-effect transistors (MOSFETs) are used in various electronic devices but not specifically designed for microwave and higher frequency RF operation.

The low noise amplifier is the first step in the receive signal path because it amplifies the weak incoming signal from the antenna while introducing minimal noise. This is crucial to improve the signal-to-noise ratio and ensure that the subsequent stages of signal processing can accurately detect and decode the desired information. The down converter, up converter, and demodulator come into play after the signal has been amplified by the low noise amplifier.

The correct answer is orbit prediction, antenna pointing, satellite acquisition, and satellite tracking. This sequence of events makes logical sense when establishing a communication link with a satellite. First, the orbit prediction is necessary to determine the satellite's location and trajectory. Then, the antenna needs to be pointed in the direction of the satellite to establish a connection. Once the antenna is properly aligned, the satellite acquisition process can begin, where the satellite is identified and locked onto. Finally, satellite tracking ensures that the communication link remains stable and the satellite is continuously monitored.

The programmed track method requires no input from a satellite because it relies on pre-programmed instructions and coordinates to determine the position and movement of an object. This method is often used in scenarios where a satellite-based tracking system is not available or necessary, such as in controlled environments or when tracking objects with predictable paths. Automatic track, pseudoconscan, and step track methods, on the other hand, typically rely on satellite input or continuous monitoring to track and update the position of an object.

The up converter is used to produce the final transmit frequency in a SATCOM system. This module takes the intermediate frequency signal and converts it to the desired frequency for transmission. It increases the frequency of the signal to the appropriate level for transmission through the antenna. The modulator is responsible for modulating the signal, the amplifier amplifies the signal, and the antenna transmits the signal, but none of these modules specifically produce the final transmit frequency. Therefore, the up converter is the correct answer.

Satellite communication (SATCOM) requires three distinct elements to work together: the space segment, control segment, and terminal segment. The space segment refers to the satellites themselves, which transmit and receive signals. The control segment consists of ground-based control stations that manage and monitor the satellites. The terminal segment includes the equipment used by users to send and receive signals. The payload segment, on the other hand, refers to the part of the satellite that carries the communication payload, such as the transponders or antennas. It is not one of the three elements that work together to make SATCOM possible.

Crosslinking refers to the capability of a satellite to communicate directly with other satellites in the same constellation, without the need for ground-based infrastructure. This is different from previous military satellite communications (MILSATCOM) and commercial satellite communications systems, which rely on ground-based stations to relay information. Crosslinking allows for faster and more secure communication between satellites, making it a unique and advanced feature of the MILSTAR system.

Ku-band service for commercial satellite services is not available worldwide. It is primarily located over land masses and highly populated areas. This means that the coverage is more focused on areas with higher population density and economic activity, rather than providing global coverage.

The MILSTAR satellite sends downlink communications transmissions at ultrahigh frequency (UHF) and super-high frequency (SHF). This means that the satellite is capable of transmitting signals at both UHF and SHF frequencies. UHF frequencies range from 300 MHz to 3 GHz, while SHF frequencies range from 3 GHz to 30 GHz. By using both UHF and SHF frequencies, the MILSTAR satellite can ensure reliable and efficient communication for military strategic and tactical purposes.

Wavelength division multiplexing assigns each incoming optical signal a specific frequency of light. This technique allows multiple signals to be transmitted simultaneously over a single optical fiber by assigning different wavelengths to each signal. Each signal is then encoded with its respective frequency, allowing for efficient and simultaneous transmission of multiple signals without interference.

The element of the MILSTAR mission that allocates communication resources is "Planning." This involves determining how the available communication resources will be distributed and utilized to support the mission objectives effectively. Planning ensures that the right amount of resources is allocated to different units and operations, taking into account factors such as priority, capacity, and availability. It involves coordinating and scheduling communication activities to ensure efficient and reliable communication throughout the mission.

The Ultrahigh frequency (UHF) follow-on satellite system provides Global Broadcast Services (GBS). This system is specifically designed to deliver high-capacity, worldwide broadcasting of digital multimedia information to users in the UHF frequency band. It enables the transmission of data, voice, and video to military forces, providing them with critical information and updates in real-time.

The SATCOM control segment is responsible for managing and coordinating the satellite communications network. It includes functions such as spacecraft control, network control, and payload control. However, ground control is not a function of the control segment. Ground control refers to the operation and management of ground-based equipment and facilities, which is not directly related to the control segment's responsibilities in managing the satellite network.

The correct answer is time. Time division multiplexing (TDM) is a multiplexing division technique that samples each low-speed channel in sequence, interleaves the bits or characters, and then transmits them at a high speed. TDM assigns a specific time slot to each channel, allowing multiple channels to share the same transmission medium.