What is the 3 dB beamwidth of the antenna radiation pattern shown in Figure E9-1?

1. A 75 degrees
2. B 50 degrees
3. C 25 degrees
4. D 30 degrees

What is the front-to-back ratio of the antenna radiation pattern shown in Figure E9-1?

1. A 36 dB
2. B 14 dB
3. C 24 dB
4. D 18 dB

What is the front-to-side ratio of the antenna radiation pattern shown in Figure E9-1?

1. A 12 dB
2. B 24 dB
3. C 18 dB
4. D 14 dB

What is the front-to-back ratio of the radiation pattern shown in Figure E92?

1. A 15 dB
2. B 28 dB
3. C 3 dB
4. D 38 dB

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

1. A Elevation
2. B Azimuth
3. C Near field
4. D Polarization

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

1. A 45 degrees
2. B 75 degrees
3. C 7.5 degrees
4. D 25 degrees

What is the difference in radiated power between a lossless antenna with gain and an isotropic radiator driven by the same power?

1. A The power radiated from the directional antenna is increased by the gain of the antenna
2. B The power radiated from the directional antenna is stronger by its front-to-back ratio
3. C They are the same
4. D The power radiated from the isotropic radiator is 2.15 dB greater than that from the directional antenna

What is the far field of an antenna?

1. A The region of the ionosphere where radiated power is not refracted
2. B The region where radiated power dissipates over a specified time period
3. C The region where radiated field strengths are constant
4. D The region where the shape of the radiation pattern no longer varies with distance

What type of analysis is commonly used for modeling antennas?

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

What is the principle of a Method of Moments analysis?

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

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

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