120. Which antenna does not depend on frequency?
A. Yagi-Uda
B. Folded-dipole
C. Log periodic antenna
D. None of the above

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121. The parabolic and lens antennas are used extensively at
A. SW
B. MW
C. Microwaves
D. All of the above

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122. The radiation pattern of helical antenna (axial mode) is represented by
A. figure A
B. figure B
C. figure C
D. figure D

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123. In E-plane metal plate lens antenna
A. travelling wave fronts are retarded
B. tavelling wave front are accelerated
C. travelling wave front remains unaffected
D. None of the above

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124. In H-plane metal plate lens the travelling wave front is
A. totally retarded
B. retarded
C. accelerated
D. neither accelerated nor retarded

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125. Antenna radiation efficiency is given by Radiation resistance
A. Antenna resistance
B. Antenna resistance
C. Radiation resistance
D.Maximum power gain

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126. Antenna aperture efficiency is given by
A. DX2
B.47cDX2
C. 47cA
D. 4nA

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