On This Page
This set of Antennas and Microwave Engineering Multiple Choice Questions & Answers (MCQs) focuses on Antennas And Microwave Engineering Set 2
Q1 | If the beam width of an antenna in two orthogonal planes are 300 and 600. Then the directivity of the antenna is:
- 24
- 18
- 36
- 12
Q2 | If the power input to an antenna is 100 mW and if the radiated power is measured to be 90 mW, then the efficiency of the antenna is:
- 75 %
- 80 %
- 90 %
- insufficient data
Q3 | If an antenna has a directivity of 16 and radiation efficiency of 0.9, then the gain of the antenna is:
- 16.2
- 14.8
- 12.5
- 19.3
Q4 | Gain of an antenna is always greater than the directivity of the antenna.
- true
- false
Q5 | A rectangular horn antenna has an aperture area of 3λ × 2λ. Then the maximum directivity that can be achieved by this rectangular horn antenna is:
- 24 db
- 4 db
- 19 db
- insufficient data
Q6 | A rectangular horn antenna has an aperture area of 3λ × 2λ. If the aperture efficiency of an antenna is 90%, then the directivity of the antenna is:
- 19 db
- 17.1 db
- 13 db
- 21.1 db
Q7 | A resistor is operated at a temperature of 300 K, with a system bandwidth of 1 MHz then the noise power produced by the resistor is:
- 3.13×10-23 watts
- 4.14×10-15 watts
- 6.14×10-15 watts
- none of the mentioned
Q8 | With an increase in operating frequency, the background noise temperature:
- increases
- decreases
- remains constant
- remains unaffected
Q9 | The noise temperature of an antenna is given by the expression:
- radtb + (1-rad) tp
- (1-rad) tp
- radtb
- none of the mentioned
Q10 | Low is the G/T ratio of an antenna, higher is its efficiency.
- true
- false
Q11 | has a constant power spectral density.
- white noise
- gaussian noise
- thermal noise
- shot noise
Q12 | Slotted line is a transmission line configuration that allows the sampling of:
- electric field amplitude of a standing wave on a terminated line
- magnetic field amplitude of a standing wave on a terminated line
- voltage used for excitation
- current that is generated by the source
Q13 | A modern device that replaces a slotted line is:
- digital cro
- generators
- network analyzers
- computers
Q14 | If the standing wave ratio for a transmission line is 1.4, then the reflection coefficient for the line is:
- 0.16667
- 1.6667
- 0.01667
- 0.96
Q15 | If the reflection coefficient of a transmission line is 0.4, then the standing wave ratio is:
- 1.3333
- 2.3333
- 0.4
- 0.6
Q16 | In the expression for phase of the reflection coefficient, Lmin stands for :
- distance between load and first voltage minimum
- distance between load and first voltage maximum
- distance between consecutive minimas
- distance between a minima and immediate maxima
Q17 | If the normalized load impedance of a transmission line is 2, then the reflection co- efficient is:
- 0.33334
- 1.33334
- 1
Q18 | Link budget consists of calculation of
- useful signal power
- interfering noise power
- useful signal & interfering noise power
- none of the mentioned
Q19 | Which is the primary cost for degradation of error performance?
- loss in signal to noise ratio
- signal distortion
- signal distortion & loss in signal to noise ratio
- none of the mentioned
Q20 | Which factor adds phase noise to the signal?
- jitter
- phase fluctuations
- jitter & phase fluctuations
- none of the mentioned
Q21 | Antennas are used
- as transducer
- to focus
- as transducer & to focus
- none of the mentioned
Q22 | Mechanism contributing to a reduction in efficiency is called as
- amplitude tapering
- blockage
- edge diffraction
- all of the mentioned
Q23 | Space loss occurs due to a decrease in
- electric field strength
- efficiency
- phase
- signal power
Q24 | Antenna’s efficiency is given by the ratio of
- effective aperture to physical aperture
- physical aperture to effective aperture
- signal power to noise power
- losses
Q25 | Effective radiated power of an isotropic radiator can be given as a product of
- radiated power and received power
- effective area and physical area
- transmitted power and transmitting gain
- receiving power and receiving gain