Radar OSA Practice Test

These questions are part of the practice quiz. Start practicing

• Which weather condition corresponds to the indicated maximum on the radar readout?
• If an antenna has a directivity of 10 and an aperture efficiency of 0.5, what is the resulting gain?
• Define antenna beamwidth and explain how aperture size affects angular resolution.
• Which statement best describes atmospheric attenuation in radar?
• Which EMI category includes thunderstorms and solar/interstellar radiation?
• Which term denotes the source that delivers live data to the bridge?
• Which term provides non real-time data for over the horizon contacts?
• What is the term for the adjustment of the vertical angle of the antenna after each complete revolution?
• Which term describes random and automatic jumping of frequencies in specific bands with carrier changes between pulses?
• In radar detection, clutter modeling influences detection by predicting clutter statistics. Which statement is true and which models are commonly used?
• Which feature defines pulse width in radar terminology?
• What effect does pulse compression have on range resolution?
• Which term describes the ability of the ship's master to enter voyage-related information such as draft, hazardous cargo, destination, and estimated time of arrival?
• What is the difference between clutter maps and adaptive filtering in radar signal processing?
• What term describes the reduction in RF wave strength due to scattering or absorption in the atmosphere?
• Which statement best describes the difference between baseband processing and IF processing in a radar receiver?
• Which method best mitigates side lobes in radar systems?
• If you see the number 73 on the display, which radar functions are active?
• Sea clutter in radar is best described as which type of return?
• Which statement best describes how radar-absorbent or composite materials affect radar energy?
• Which type of EMI is associated with thunderstorms and solar radiation?
• Which mode is used to track one or more targets while scanning for others?
• Radar systems determine a contact's direction and range using which form of energy?
• What does the Rough indication signify on the STC control feature?
• What is the characteristic of circular scanning radar?
• Calm seawater is described as a good conductor; why does it allow radar waves to travel greater distances along its surface?
• What is the bow bearing of a ship relative to itself?
• Which statement correctly expresses the relationship among antenna gain, aperture efficiency, and directivity?
• Which parameter primarily determines the maximum range at which a usable echo can be received?
• PRT is the time between the beginning of one pulse and the start of the next pulse. Which statement is true?
• What is Moving Target Indication (MTI) used for in radar systems?
• What is the characteristic of linear scanning radar?
• The timing sliders control which parameter on the radar R/T?
• Which factor is closely associated with how much a radar can detect due to the object's geometry?
• If 1 NM equals 2,000 yards according to the material, how many yards are in 3 NM?
• How does target aspect angle influence measured RCS and detection probability?
• Which data category includes real-time changes such as position and speed?
• Which of the following is NOT a common sea clutter mitigation technique?
• In a range-Doppler map, which axis corresponds to velocity information?
• What is CFAR and how does it adapt the detection threshold in clutter?
• Increasing the pulse repetition frequency (PRF) has what effect on unambiguous range and Doppler unambiguity?
• What does the Calm indication signify on the STC control feature?
• Non-metal boats such as wooden, fiber glass, fishing boats or sailboats may not be picked up by radar. Which option best reflects this statement?
• Which term is measured by noting the time it takes a signal to make a round-trip to the target and back?
• Which technique uses polarization to mitigate sea clutter?
• How does received power scale with range R in the basic radar range equation, with all other factors fixed?
• Which category includes interference from radio transmissions or electronic fields generated by electronic equipment?
• Radar Cross Section is a measure of a target's ability to reflect radar signals. Which attributes are involved?
• Which condition corresponds to the 'indicated maximum' on the radar readout?
• What is calibration in radar systems and why is it essential?
• Which term provides non real-time data for long-range contacts?
• In radar terminology, what does absorption refer to?
• Which term best describes deliberate external interference designed to render radar useless?
• Relative bearing is in relation to what reference on a ship?
• The abbreviation MBST stands for which phrase?
• Which term describes the system that provides real-time data (live right now)?
• Which radar detection technique uses clutter models to set adaptive thresholds?
• Which statement about AIS on a US Navy ship is accurate?
• What is formed when a surface duct is created by trapping a layer of air between two different temperatures?
• What are the four data categories in AIS?
• What is the significance of range-Doppler coupling and how is it addressed?
• What is the primary purpose of EMCON in radar operations?
• What is the function of anti-jam controls?
• The static data category describes what?
• What is a ROC curve and how do you interpret Pd vs Pfa?
• Which statement correctly describes true north when the bearing is 000 degrees?
• What is NIPRNET?
• The number 73 indicates which combination of radar functions?
• AIS transmissions on a US Navy ship are configured for what?
• Which hull material reduces radar reflectivity to radar energy?
• What is the purpose of calibration loops in radar and typical calibration methods?
• What does the STC control slider adjust on the radar control panel?
• Which statement best defines amplitude in radar terminology?
• What does diversity do in the context of radar waveform management?
• Radar horizon is best described as what?
• Which statement about jamming is true?
• Which statement correctly describes the relationship between system noise temperature and the noise figure in a radar receiver?
• Explain the concept of beat frequency and the purpose of the IF stage in a radar receiver.
• Which condition is commonly cited as an absorption example in radar context?
• If T0 is 290 K and T_noise is 60 K, what is the approximate noise figure F?
• Which term is the direction from which the reflected signal is received, expressed in compass points or degrees?
• What do the Swerling target models I-IV describe, and how do they affect detection?
• What does RCS stand for and what does it measure?
• Which term represents entering voyage-related details such as draft and ETA?
• What is pulse compression, and how does matched filtering contribute to processing gain?
• Which statement about ROC curves is most accurate?
• Which weather condition corresponds to the indicated minimum on the radar readout?
• In track maintenance, what is the primary purpose of gating?
• Which setting indicates maximum STC, resulting in more attenuation close in?
• The indicator 67 on the radar readout corresponds to which radar functions?
• Which term describes sweeping a thin beam horizontally to cover a rectangular area?
• What determines range resolution in a pulsed radar, and what is the role of pulse compression?
• Which description best captures the role of Band J equipment including Doppler navigation radar and related systems?
• Which statement describes MBST in the radar system?
• Which term describes the network used for unclassified military communications in the AIS context?
• MBST stands for what?
• What is the significance of a ROC curve in detector design and how is it used to select thresholds?
• Which term is defined as the space occupied by one cycle?
• What is the effect of multipath on radar performance and how can it be mitigated?
• Which term is used to broadcast safety alerts like a fire on board or medical emergency?
• Which description matches a unidirectional scan pattern?
• Which statement about bearing 000 degrees is true?
• How many yards are in 1 nautical mile (as defined in the material)?
• Which term relates to sending safety messages for emergencies such as fire on board or a medical emergency?
• What is the primary purpose of clutter suppression in radar detection?
• How does atmospheric attenuation affect radar performance and at what bands is it most significant?
• What term describes the time required for the antenna to complete one scan cycle?
• Explain the role of the intermediate frequency (IF) stage in a radar receiver.
• Which property of an object affects the reflection of radio waves?
• Which term refers to the vertical angle adjustment of the antenna during scanning?
• Which expression correctly gives the maximum unambiguous Doppler velocity, given that f_d,max = PRF/2 and v_max = (f_d,max λ)/2?
• What is T/R duplexing and why do radars share an antenna for transmit and receive?
• Which term describes the loss of radar energy to the medium?
• Which parameter controls changes in the pulse repetition rate (PRR) or pulse repetition frequency (PRF)?
• Which EMI category arises from radio transmissions or electronic fields generated by electronic equipment?
• PRT is the time between the beginning of one pulse and the start of the next pulse, and it is equal to the reciprocal of what?
• What is the role of anti jamming circuits?
• How does coherent integration affect the signal-to-noise ratio, and what limits the number of pulses that can be coherently accumulated?
• What is the pulse repetition frequency (PRF)?
• Which antenna type is designed for precision, narrow pulse, and narrow beam width?
• What determines the unambiguous Doppler velocity?
• How do polarization properties affect radar detection and clutter suppression?
• Azimuth in radar terminology is best described as what?
• Which phenomenon occurs when radio waves bend around an obstacle that blocks the direct path?
• Circular scanning radar uses an attune system to continuously scan how many degrees in azimuth?
• Which of the following is NOT a typical radar calibration method?
• What is a Doppler map (range-Doppler) and what information does it provide?
• How does the choice of waveform (e.g., LFM vs phase codes) affect detection and range resolution?
• In radar signal processing, what challenge does multi-target tracking address compared to single-target tracking?
• Distinguish between radar search mode and track mode.
• What effect do poor conductors have on radio waves?
• What is AIS?
• What is autofocus in radar processing used for?
• Which term refers to ships navigation interfaces?
• Why is windowing used in pulse compression, and what is its effect on range sidelobes?
• What does static AIS data refer to?
• Which polarization property can help suppress clutter and improve detection?
• Explain the concept of dynamic range in radar receivers.
• Atmospheric incidences include temperature inversion and evaporation of water from cool sea air into the lower levels of warm dry air. Which option lists this combined effect?
• Which term refers to interference from external sources that can render a radar system useless?
• Which phenomenon occurs when RF energy is refracted or bent as waves pass from one material to another of different density?
• How does EMCON typically change with increasing frequency and bandwidth?
• In transmitter operation, frequency is defined as what?
• What is range gating and why is it used in radar receivers?
• How do digital beamforming and phased arrays enable flexible scanning?
• The indicator 73 on the radar readout corresponds to which radar functions?
• If you see the number 67 on the display, which radar functions are active?
• What information does AIS exchange?
• What is STC used for in radar operation?
• What does the FTC control slider adjust?
• Which material typically reflects radar energy best at long range?
• How many data categories are there in AIS data categories?
• Band F corresponds to which type of radar?
• How does clutter suppression interact with track initiation and maintenance in a radar system?
• How does aspect angle affect the radar cross section σ?
• Doppler clutter suppression uses Doppler filtering to remove clutter around zero Doppler. What are its typical limitations?
• Which term refers to a constant variation or jumping of frequencies over the spectrum?
• Which factor most directly limits the maximum detectable signal before saturation occurs?
• Why are side lobes a concern in radar systems and how can they be mitigated?
• Which factor directly increases the ability to reposition the radar beam quickly?
• Radar detection is least likely to pick up which type of vessel?
• Band J is associated with which group of radar types?
• Which phenomenon occurs when radio waves bend around an obstruction?
• Which statement best describes track initiation and track maintenance in a multi-target tracker?
• What is radar cross section (RCS)?
• What does the AIS server do?
• Peak power determines what regarding the echo?
• What does VMS provide on an electronic chart?
• Linear scanning radar is associated with which beam characteristic?
• Which condition causes radar energy to deflect, absorb, or reflect due to rapid changes in temperature and water vapor?
• Natural electromagnetic interference is most erratic in which band?
• The MBST voltage is a parameter of which radar component?
• Which term refers to a system that provides non real-time data to allow it to interface with other systems?
• For a target moving directly toward the radar with radial velocity v, what is the Doppler shift relation and how is velocity recovered?
• Which statement describes the radar horizon relative to the visual horizon?
• Who is the only person to put AIS into transmit mode?
• Which term is the space occupied by one cycle?
• Which description best matches agility in radar systems?
• Which statement correctly describes metal in radar detection?
• Which atmospheric incidence is described as trapping a cold air layer between two different temperatures?
• In radar signal processing, what distinguishes single-target tracking from multi-target tracking?
• Which antenna type is described as being designed for precision with a narrow beam width?
• Composite or radar absorbent material affect radar energy by doing what?
• What is scattering in radar terms?
• Which term is one complete reversal of an alternating current, starting at zero and going through a positive peak?
• What is the basic AIS mode configuration at unit level?
• What is the unambiguous range for a radar given a certain PRF?
• What is CFAR adaptation in radar, and how does it affect thresholding?
• What distinguishes hardware-based autofocus from digital autofocus in radar systems?
• What is the primary purpose of AIS data exchange?
• Which term describes using a thin beam to cover a rectangular area by horizontally sweeping?
• Which atmospheric layer's disturbances can reflect radar performance due to magnetic storms?
• Where is the MBST value displayed?
• In the basic radar range equation, what does sigma (σ) represent?
• Explain the role of a phase-locked oscillator (PLO) and how phase noise impacts radar performance.
• Which statement best describes coherent processing in radar systems?
• What are blind speeds in Doppler radar, and why do they occur?
• Doppler frequency maps to which radar observable?
• Why is Nyquist sampling relevant in radar data acquisition?
• What is phase noise and how does it affect coherent detection?
• Which radar parameter largely determines the minimum range?
• What determines the unambiguous range in pulsed radar operation?
• Which factor directly affects how much radar energy is reflected by an object?
• Regarding threshold setting in detection, which statement is true about Pfa and Pd?
• Min/Max range is achieved by using what pulse strategy?
• Which factor most affects an object's visibility on radar based on its surface orientation?
• Band J includes which of the following radar systems?
• In detector design, which statement best describes threshold selection?