Description : A type of array antenna which consists of one half-wave driven dipole, one reflector and one director A. Hertzian dipole B. Yagi-uda C. Broadside collinear D. Log periodic dipole array
Last Answer : B. Yagi-uda
Description : It consists of a number of dipoles of equal size, equally spaced along a straight line with all dipoles fed in the same phase from the same source. A. Log-periodic antenna B. Yagi antenna C. End-fire array D. Broadside array
Last Answer : D. Broadside array
Description : Good grounding is important for A. horizontal antennas B. broadside array antennas C. vertical antennas D. Yagi-Uda antennas
Last Answer : C. vertical antennas
Description : ______ is an antenna array which is highly directional at right angles to the plane of the array? A. Broadside array B. End-fire array C. Turnstile array D. Log-periodic array
Last Answer : A. Broadside array
Description : Best description of a collinear and broadside antenna radiation pattern. A. Bidirectional B. Perfect circle C. Unidirectional D. Omnidirectional
Last Answer : A. Bidirectional
Description : One ofthe followingconsistsof nonresonant antennas: a.The rhombic antenna b. The folded dipole c. The end-fire array d. The broadside array
Last Answer : a.The rhombic antenna
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 : Which of the following antennas receive signals in the horizontal plane equality well from all directions? A. Horizontal Hertz antenna B. Vertical loop antenna C. Vertical Yagi antenna D. A vertical antenna which is a quarter-wavelength long
Last Answer : D. A vertical antenna which is a quarter-wavelength long
Description : Which of the following antennas require good grounding? A. Yagi antenna B. Hertz antenna C. Marconi antenna D. Isotropic antenna
Last Answer : C. Marconi antenna
Description : Which of the following antennas receives signals equally well from all directions in a horizontal plane? A. Hetz antenna B. Vertical Marconi antenna C. Yagi antenna D. Helical antenna
Last Answer : B. Vertical Marconi antenna
Description : Which is the non-resonant antenna? A. Broadside Antenna B. Folded Dipole C. Rhombic antenna D. End fire array
Last Answer : C. Rhombic antenna
Description : A theoretical reference antenna that provides a comparison for antenna measurements. A. Marconi antenna B. Isotropic radiator C. Yagi-Uda array D. Whip antenna
Last Answer : B. Isotropic radiator
Description : Which is a non-resonant antenna? A. Rhombic antenna B. Folded dipole C. End-fire array D. Yagi-Uda antenna
Last Answer : A. Rhombic antenna
Description : Receives and collects satellite signals form a broadcast satellite. A. LNB B. Yagi-Uda array C. Satellite receiver D. Satellite disk
Last Answer : D. Satellite disk
Description : The broadside array consists of a flat reflector and what other elements?
Last Answer : Two or more half-wave dipoles.
Description : As the spacing between elements in a broadside array increases, what is the effect on the major lobes?
Last Answer : They sharpen.
Description : When more than two elements are used in a broadside array, how are the elements arranged?
Last Answer : Parallel and in the same plane.
Description : The radiation pattern of collinear and a broadside antenna is __
Last Answer : bidirectional
Description : _____ is an antenna made up of a number of full wavelengths A. Elementary doublet B. Log-periodic C. Long wire D. Whip
Last Answer : C. Long wire
Description : What is the advantage of adding parasitic elements to a Yagi array?
Last Answer : Increased gain.
Description : How is directivity of a collinear array affected when the number of elements is increased?
Last Answer : Directivity increases.
Description : Why is the number of elements used in a collinear array limited?
Last Answer : As more elements are added, an unbalanced condition in the system occurs which impairs efficiency.
Description : What is the maximum number of elements ordinarily used in a collinear array?
Last Answer : Four.
Description : How does spatial isolation technique in satellite communications avoid interference? A. Use of different polarity antennas B. Use of different types of antennas C. Employment of highly directional spot-beam antennas D. Use of low gain antennas
Last Answer : C. Employment of highly directional spot-beam antennas
Description : Which of the following refers to the smallest beam of a satellite antenna’s radiation pattern A. Global beam B. Spot beam C. Zone beam D. Hemispheric beam
Last Answer : B. Spot beam
Description : Which of the following refers to the smallest beam of satellite antenna’s radiation pattern? A. Hemispheric beam B. Spot beam C. Zone beam D. Global beam
Description : Write the application of the following antennas: 1) Rectangular antenna 2) Dish antenna 3) Horn antenna 4) Loop antenna 5) Yagi-Uda antenna.
Last Answer : Applications: 1.Rectangular antenna i)Used in Mobile and satellite communication ii)Used in Global Positioning System iii) Used for Radio Frequency Identification (RFID) iv) Radar Dish ... antenna. 2. Yagi-Uda antenna is used in conditional Access System (CAS) at the decryptor.
Description : The effect of adding parasitic elements of a Hertz dipole is to A. make the antenna more omnidirectional B. reduce its resonant frequency C. increase the antenna’s power gain D. All of these
Last Answer : C. increase the antenna’s power gain
Description : One of the following is very useful as a multiband HF receiving antenna. A. Parabolic antenna B. Elementary doublet C. Log-periodic D. Square loop
Last Answer : C. Log-periodic
Description : Modulation in which the modulated wave is always present. A. Carrier modulation B. Front-end C. Continuous modulation D. Log-periodic modulation
Last Answer : C. Continuous modulation
Description : Two wires that are bent 90 degrees apart. A. Hertz B. Dipole C. Log-periodic D. Rhomic
Last Answer : B. Dipole
Description : Factors that determine the radiation resistance of an antenna A. Transmission line length and height of antenna B. The location of the antenna with respect to nearby objects C. It is a constant for all antennas since it is physical D. Sunspot activity and the time of day
Last Answer : B. The location of the antenna with respect to nearby objects
Description : It is useful to refer to an isotropic radiator. A. when comparing the gains of directional antennas B. when testing a transmission line for standing wave ratio C. when (in the northern hemisphere) directing the transmission D. when using a dummy load to tune a transmitter
Last Answer : A. when comparing the gains of directional antennas
Description : When is it useful to refer to an isotropic radiator? A. When comparing the gains of directional antennas B. When testing a transmission line for standing wave ratio C. When (in the northern ... ) directing the transmission in a southerly direction D. When using a dummy load to tune a transmitter
Last Answer : A. When comparing the gains of directional antennas
Description : ECE Board Exam March 1996 When the transmitting and receiving antennas are in line-of-sight of each other, the mode of propagation is ________ wave. A. space or direct B. ground C. surface D. sky
Last Answer : A. space or direct
Description : The Yagi antenna is an example of what type of array?
Last Answer : Multielement parasitic array.
Description : How can the frequency range of a collinear array be increased?
Last Answer : By increasing the lengths of the elements of the array.
Description : In order to get maximum radiation to all surrounding points in the horizontal plane, the antenna used is a A. vertical loop B. vertical quarter-wavelength rod C. array which includes parasitic elements D. a horizontal Hertz dipole
Last Answer : B. vertical quarter-wavelength rod
Description : If the current ratios of the two or more elements must be held 5% and the phase angle to 3° the antenna is called a A. end fire array B. critical phased array C. broadband array D. wideband array
Last Answer : B. critical phased array
Description : What circuit is responsible in activating and deactivating adjacent antenna elements in a mobile satellite array? A. Radial divider B. Divider/combiner C. Radial combiner D. Radial multiplexer
Last Answer : A. Radial divider
Description : In a typical mobile satellite array antenna if three elements are activated, how many elements are deactivated? A. 3 B. 11 C. 5 D. 9
Last Answer : B. 11
Description : A mobile satellite array has usually how many elements? A. 6 B. 88 C. 12 D. 14
Last Answer : D. 14
Description : The reflector and director of an antenna array are considered as A. Parasitic elements B. Transcendental elements C. Feed-points D. Driven elements
Last Answer : A. Parasitic elements
Description : _____ is an antenna with a number of half-wave antenna on it. A. Antenna array B. Tower C. Omni-directional D. Rhombic
Last Answer : A. Antenna array
Description : Which antenna does not use the ground? A. Marconi B. Yagi C. Hertz D. Rhombic
Last Answer : B. Yagi
Description : Which antenna is a properly terminated? A. Marconi B. Rhombic C. Dipole D. Yagi-Uda
Last Answer : B. Rhombic
Description : Type of antenna which is normally used for satellite tracking service. A. Omni B. Helical C. Yagi D. Dipole
Last Answer : B. Helical
Description : An antenna that can only receive a television signal. A. Isotropic antenna B. TVRO C. Reference antenna D. Yagi antenna
Last Answer : B. TVRO
Description : Collects very weak signal from a broadcast satellite A. Satellite dish B. LNB C. Yagi-Uda antenna D. Satellite receiver
Last Answer : A. Satellite dish
Description : When antennas are closed to the ground, _______ polarization is ideal A. horizontally polarized B. vertically polarized C. circularly polarized D. both A and B
Last Answer : B. vertically polarized