antenna v1

An antenna, in addition to radiating or receiving energy, is also used to ____ energy in some directions and suppress in others.

• a) Dissipate

• b) Generate noise

• c) accentuate

A radiator having equal radiation in all directions is referred to as a:

• a) directional radiator

• b) isotropic radiator

• c) guided radiator

If charge is moving with constant velocity, radiation can be created by ___ .

• a) smooth wires

• b) bent wires

• c) infinite length wires

The angular separation between two identical points on an amplitude pattern of an antenna is referred to as the:

• a) bandwidth

• b) beamwidth

• c) loop

An aggregate of individual discrete radiating elements (antennas) in an electrical and geometrical arrangement is referred to as a ___ .

• a) continuous source

• b) wave guide

• c) array

The radiation lobe opposite to the major lobe is called ___

• a) minor

• b) back

The normalized power pattern of antenna is represented as U(𝜃)=sin^2 (𝜃). Then HPBW of antenna is equal to

• a) 90

• b) 60

• c) 120

The maximum directivity (dimensionless) of a half-wavelength dipole, with an idealized sinusoidal current distribution, is:

• a) 1.5

• b) 4

• c) 1.64

The ratio of the gain to the directivity of an antenna is defined as the

• beam efficiency

• b) Radiation efficiency

The real parts of the input impedance of an antenna are referred to as the

• a) reflection resistance

• b) radiation resistance

• c) Radiation reactance