E9B01:

In the antenna radiation pattern shown in Figure E9-1, what is the beamwidth?

1. 75 degrees
2. 50 degrees
3. 25 degrees
4. 30 degrees

E9B02:

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

1. 36 dB
2. 18 dB
3. 24 dB
4. 14 dB

E9B03:

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-side ratio?

1. 12 dB
2. 14 dB
3. 18 dB
4. 24 dB

E9B04:

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

1. 15 dB
2. 28 dB
3. 3 dB
4. 38 dB

E9B05:

What type of antenna pattern is shown in Figure E9-2?

1. Elevation
2. Azimuth
3. Radiation resistance
4. Polarization

E9B06:

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

1. 45 degrees
2. 75 degrees
3. 7.5 degrees
4. 25 degrees

E9B07:

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from a theoretical isotropic antenna, assuming each is driven by the same amount of power?

1. The total amount of radiation from the directional antenna is increased by the gain of the antenna
2. The total amount of radiation from the directional antenna is stronger by its front-to-back ratio
3. They are the same
4. The radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna

E9B08:

What is the far field of an antenna?

1. The region of the ionosphere where radiated power is not refracted
2. The region where radiated power dissipates over a specified time period
3. The region where radiated field strengths are constant
4. The region where the shape of the antenna pattern is independent of distance

E9B09:

What type of computer program technique is commonly used for modeling antennas?

1. Graphical analysis
2. Method of Moments
3. Mutual impedance analysis
4. Calculus differentiation with respect to physical properties

E9B10:

What is the principle of a Method of Moments analysis?

1. A wire is modeled as a series of segments, each having a uniform value of current
2. A wire is modeled as a single sine-wave current generator
3. A wire is modeled as a single sine-wave voltage source
4. A wire is modeled as a series of segments, each having a distinct value of voltage across it

E9B11:

What is a disadvantage of decreasing the number of wire segments in an antenna model below 10 segments per half-wavelength?

1. Ground conductivity will not be accurately modeled
2. The resulting design will favor radiation of harmonic energy
3. The computed feed point impedance may be incorrect
4. The antenna will become mechanically unstable