CHAPTER 15: Microwaves & Lasers

Which is not a type of horn antenna design for microwave frequencies?

a. Parabolic horn

b. Circular horn

c. Pyramidal horn

d. Sectoral horn

A

Cassegrain feed to a paraboloid antenna involves a

a. Dipole antenna

b. Point-source antenna

c. Secondary reflector

d. Any of the above

C

Calculate the beamwidth of a microwave dish antenna with a 6-m mouth diameter when used at 5 Ghz.

a. 0.49°

b. 4.9°

c. 7°

d. 0.7°

D

Zoning refers to

a. A method of producing a radome

b. Changing a spherical wavefront into a plane wave

c. Creating a polar radiation pattern

d. Fading into nonreality

B

Which microwave oscillator has high gain, low-noise characteristics, and wide bandwidth?

a. Traveling wave tube oscillator

b. Gunn Oscillator

c. Klystron oscillator

d. Magnetron oscillator

A

Which is not an advantage of the Gunn gallium arsenide oscillator?

a. Ease of removing heat from the chip

b. Small size

c. Ruggedness

d. Lack of filaments

e. Low cost of manufacture

A

The i in P-I-N diode refers to

a. Indium

b. Impact

c. Integrated

d. Intrinsic

D

Which is not a typical application of a ferrite in a microwave system?

a. attenuator

b. amplifier

c. isolator

d. circulator

B

A low noise microwave amplifier that provides amplification via the variation of a reactance is known as a

a. Maser

b. Laser

c. Yig

d. Parametric amplifier

D

The major difference between a laser and a maser is the

a. Frequency of the signal being amplified

b. Amplitude of the signal being amplified

c. Bandwidth of the signal being amplified

d. Phase of the signal being amplified

A

Lasers are useful in

a. Industrial welding

b. Surgical procedures

c. Distance measuring

d. Compact disc players

e. All the above

E

The following semiconductor is not used as a microwave device:

a. PIN diode

b. Baritt diode

c. Zener diode

d. Tunnel diode

C

Which of the following represent typical failure mode(s) for a TWT amplifier?

a. Low gain

b. Spurious modulation

c. Poor frequency response

d. Low RF output

e. All the above

E

Which of the following is not used as a microwave antenna?

a. Patch antenna

b. Marconi antenna

c. Lens antenna

d. Horn antenna

B

Compared to linear power supplies, switching power supplies are

a. Less efficient

b. More efficient

c. Simpler

d. Heavier

B