Description : If a target is on the bearing axis of the radiated beam, what is the input to the bearing IF channel?
Last Answer : Zero.
Description : What is the term for the ration of the radiation resistance of an antenna to the total resistance of the system? A. Effective radiated power B. Beamwidth C. Radiation conversion loss D. Antenna efficiency
Last Answer : D. Antenna efficiency
Description : What is meant by the term radiation resistance for an antenna? A. The resistance in the trap coils to received signal B. An equivalent resistance that would dissipate the same amount of power as ... antenna C. The specific impedance of the antenna D. Losses in the antenna elements and feed line
Last Answer : B. An equivalent resistance that would dissipate the same amount of power as that radiated from an antenna
Description : What is meant by the term antenna efficiency? A. Efficiency = effective radiated power/transmitter output x 100% B. Efficiency = radiation resistance/ transmission resistance C. Efficiency = total resistance/radiation resistance x 100% D. Efficiency = radiation resistance/total resistance x 100%
Last Answer : D. Efficiency = radiation resistance/total resistance x 100%
Description : What determines the beam elevation angle of an antenna that is electronically scanned in elevation?
Last Answer : Frequency or phase of radiated energy.
Description : An antenna efficiency is computed by using one of the following equations. A. Efficiency = (radiation resistance / transmission resistance) B. Efficiency = (total resistance / radiation resistance) x ... / transmitter output) x 100% D. Efficiency = (radiation resistance / total resistance) x 100%
Last Answer : D. Efficiency = (radiation resistance / total resistance) x 100%
Description : The power fed to a two-bay turnstile antenna is 100 watts. If the antenna has a 2 dB power gain, what is the effective radiated power? A. 317 watts B. 158 watts C. 200 watts D. 400 watts
Last Answer : B. 158 watts
Description : _____ of an antenna is a measure of how the antenna concentrates its radiated power in a given direction. A. Efficiency B. Power C. Gain D. Polarization
Last Answer : C. Gain
Description : If the radiated power increase 10.89 times, the antenna current increases by ______. A. 3.3 times B. 6.6 times C. 1.82 times D. 10.89 times
Last Answer : A. 3.3 times
Description : How will you increase the gain of an antenna? A. By adding several antennas in parallel B. By focusing the radiated energy in one desired direction C. By making antenna rods thicker D. By making the antenna size larger
Last Answer : B. By focusing the radiated energy in one desired direction
Description : What determines antenna polarization? A. The frequency of the radiated wave B. The direction of the radiated wave C. The direction of the magnetic field vector D. The direction of the electric field vector
Last Answer : D. The direction of the electric field vector
Description : If the antenna increases 3.3 times how much does the radiated power increase? A. 3.3 times B. 10.89 times C. 9.9 times D. 6.6 times
Last Answer : B. 10.89 times
Description : What is the effective radiated power of a repeater with 200 watts transmitter power output, 4 dB feline loss, 4 dB duplexer and circulator loss, and 10 dB antenna gain? A. 317 W B. 2000 W C. 126 W D. 260 W
Last Answer : A. 317 W
Description : What is the effective radiated power of a repeater with 120 watts transmitter power output, 5 dB feedline loss, 4 dB duplexer and circulator loss, and 6 dB antenna gain? A. 601 W B. 240 W C. 60 W D. 379 W
Last Answer : C. 60 W
Description : What is the effective radiated power of a repeater with 100 watts transmitter power output, 5 dB feedline loss, 4 dB duplexer and circulator loss, and 10 dB antenna gain? A. 800 W B. 126 W C. 12.5 W D. 1260 W
Last Answer : B. 126 W
Description : What is the effective radiated power of a repeater with 75 watts transmitter power output, 5 dB feedline loss, 4 dB duplexer and circulator loss, and 6 dB antenna gain? A. 37.6 W B. 237 W C. 150 W D. 23.7 W
Last Answer : A. 37.6 W
Description : What is the effective radiated power of a repeater with 75 watts transmitter power output, 4 dB feedline loss, 3 dB duplexer and circulator loss, and 10 dB antenna gain? A. 600 W B. 75 W C. 18.75 W D. 150 W
Last Answer : D. 150 W
Description : What is the effective radiated power of a repeater with 50 watts transmitter power output, 5 dB feedline loss, 4 dB duplexer and circulator loss, and 7 dB antenna gain? A. 300 W B. 315 W C. 31.5 W D. 69.9 W
Last Answer : C. 31.5 W
Description : What is the effective radiated power of a repeater with 50 watts transmitter power output \, 4 dB feedline loss, 3 dB duplexer and circulator loss, and 6 dB antenna gain? A. 158 W B. 39.7 W C. 251 W D. 69.9 W
Last Answer : B. 39.7 W
Description : The product of antenna input power and the antenna power gain expressed in kW is called __. A. Effective Radiated Power (ERP) B. Effective Isotropic Radiated Power (EIRP) C. Radiated Power D. Transmit Power
Last Answer : A. Effective Radiated Power (ERP)
Description : The product of the radiated RF power of a transmitter and the gain of the antenna system in a given direction relative to an isotropic radiator is called ____. A. Effective Radiated Power (ERP) B. Effective Isotropic Radiated Power (EIRP) C. Radiated Power D. Transmit Power
Last Answer : B. Effective Isotropic Radiated Power (EIRP)
Description : What is the meaning of forward power? A. The power traveling from the transmitter to the antenna. B. The power radiated from the top of an antenna system. C. The power produced during the positive half of an RF cycle. D. The power used to drive a linear amplifier.
Last Answer : A. The power traveling from the transmitter to the antenna.
Description : What type of transmission is radiated from an aircraft’s radio altimeter antenna? A. An amplitude modulated continuous wave B. A pulse position modulated UHF signal C. A differential phase shift keyed UHF signal D. A frequency modulated continuous wave
Last Answer : D. A frequency modulated continuous wave
Description : Determine the effective radiated power of 20 kW TV broadcast transmitter whose antenna has a field gain of 2. A. 40 kW B. 80,000 watts C. 40,000 watts D. 8,000 watts
Last Answer : B. 80,000 watts
Description : A transmitter supplies 8 kW to the antenna when it is unmodulated, determine the total radiated power when modulated at 90%. A. 5 kW B. 20 kW C. 15 kW D. 8.36 kW
Last Answer : D. 8.36 kW
Description : An increase in the effective power radiated by an antenna in a certain desired direction at the expense of power radiated in other directions. A. Antenna gain B. Antenna back lobe ration C. Antenna total ration D. Antenna efficiency
Last Answer : A. Antenna gain
Description : How much does the radiated power of an antenna increases if its current increased by 3.3 times? A. 6.6 times B. 3.3 times C. 10.89 times D. 9.9 times
Last Answer : C. 10.89 times
Description : It is a measure of the microwave power radiated from an antenna as a function of angular direction from the antenna axis. A. Antenna pattern B. Polarization C. Beamwidth D. Sidelobes
Last Answer : C. Beamwidth
Description : What is meant by antenna gain? A. The final amplifier gain minus the transmission line losses (including any phasing lines present) B. The ratio of the amount of power produced by the antenna ... D. The numeric ratio relating the radiated signal strength of an antenna to that of another antenna
Last Answer : D. The numeric ratio relating the radiated signal strength of an antenna to that of another antenna
Description : It is the ratio of the power density radiated in a particular direction to the power density radiated to the same point by a reference antenna, assuming both antennas are radiating the same amount of power
Last Answer : directive gain
Description : When a wavefront is radiated into a waveguide, what happens to the portions of the wavefront that do not satisfy the boundary conditions?
Last Answer : Decrease to zero.
Description : What are three ways of controlling radiated emi during transmission?
Last Answer : a) physical separation of the antenna (b) limiting bandwidth of the antenna (c) use of directional antennas
Description : What width is the pulse radiated by fire-control tracking radar?
Last Answer : Very narrow.
Description : What characteristic(s) of radiated energy is (are) altered to achieve electronic scanning?
Last Answer : Frequency or phase.
Description : What is the polarization of the energy radiated by a vertical slot?
Last Answer : Horizontal.
Description : How many major lobes are radiated by a parabolic reflector?
Last Answer : One
Description : Define and explain the term beam width related to antenna with a sketch.
Last Answer : Definition: The beam width of an antenna is described as the angles created by comparing the half power point (3dB) on the main radiation lobe to its maximum power point. As an example the beam width ... max voltage at center of lobe (these point are known as half power points.) Sketch-
Description : What term is used for the end of the transmission line that is connected to an antenna?
Last Answer : Output end, receiving end, load end and sink.
Description : What term is used to express the efficiency of an antenna?
Last Answer : Power gain or power ratio
Description : The various properties of a transmitting antenna can apply equally to the same antenna when it is used as a receiving antenna. What term is used for this property?
Last Answer : Reciprocity of antennas.
Description : What is the term used to identify the points of minimum current and minimum voltage on an antenna?
Last Answer : Current and voltage nodes.
Description : What is the term used to identify the points of high current and high voltage on an antenna?
Last Answer : Current and voltage loops.
Description : What is the usual electrical length of a driven element in an HF beam antenna? A. ¼ wavelength B. ¾ wavelength C. ½ wavelength D. 1 wavelength
Last Answer : C. ½ wavelength
Description : The smallest beam of a satellite antenna radiation pattern A. Zone beam B. Hemispheric beam C. Spot beam D. Global beam
Last Answer : C. Spot beam
Description : The angle of elevation of the antenna beam is 20°. Calculate the transmission-path distance for an ionospheric transmission that utilizes a layer of virtual height 200 km. Use flat-earth approximation. A. 966 km B. 2100 km C. 1100 km D. 405 km
Last Answer : C. 1100 km
Description : Refers to a type of beam antenna which uses two or more straight elements arranged in line with each other. A. Dipole antenna B. Yagi antenna C. Whip antenna D. Rhombic antenna
Last Answer : B. Yagi antenna
Description : Adaptive array antenna is superior to switched beam antenna because: (A) It optimizes the power radiated (B) It has simpler architecture (C) It has low bandwidth (D) It has low backlobe
Last Answer : Adaptive array antenna is superior to switched beam antenna because: It optimizes the power radiated
Description : What composite field (composed of E and H fields) is found stored in the antenna?
Last Answer : Induction field.
Description : Which two composite fields (composed of E and H fields) are associated with every antenna?
Last Answer : Induction field and radiation field.
Description : If a transmitting antenna is placed close to the ground, how should the antenna be polarized to give the greatest signal strength?
Last Answer : Vertically polarized.