M.Sc. (Electronic)(Semester II) (CBCS) Examination, 2017
Microwave Engineering (Paper VI)
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Day Date: Friday, 21-04-2017 Max. Marks: 70
Time: 10.30 AM to 01.00 PM
N.B. Question number 2 and 6 are compulsory.
Attempt any three from questions number 3 to 7.
All questions carry equal marks.
Use of nonprogrammable calculator is allowed.
Q.1 Select the correct alternatives. 08
1g) In a circular waveguide, the dominate mode is
TE01 TE11 TE20 TE21
2 C band in microwave region has range.
4 to 8 GHz 18 to 26 GHz
8 to 12 GHz 26 to 40 GHz
3 The reflection coefficient on a line is 0.2 450. The SWR is
0.8 1.1 1.2 1.5
4 Which of the following is not a travelling wave?


Reflex Klystron is a
Microwave amplifier
Microwave oscillator
Microwave passive device
Microwave phase shifter
6 Which of the following parameters is negligible in transmission
lines?
R L G C
In case of open circuit transmission lines the reflection
coefficient is
1 0.5 Zero
A waveguide section in microwave circuit acts as a
Low pass filter Band pass filter
High pass filter Band reject filter
State true or false. 06
When transmission line is terminated to an open circuit, the
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SWR is infinite.
Skin effect is more pronounced at high frequencies.
Reflex klystron is essentially a low power device.
TM10 mode in rectangular waveguide has lowest cutoff
frequency.
The wavelength corresponding to a microwave frequency range
is 3 to 30 GHz.
Gauss law is not applicable to the closed surface.
Q.2 Attempt the following.
Differentiate TWT from that of the klystron. 05
Explain what do you mean by waveguide phase shifter. 05
Mention the applications of microwaves. 04
Q.3 Derive an expressions for cut off frequency and phase constant in a
rectangular wave guide.
10
What are strip lines? Mention their advantages over transmission
lines.
04
Q.4 A 600 MHz electromagnetic wave is propagating through a perfect
nonmagnetic dielectrics having Calculate
Wavelength and phase constant.
With wave travelling in the direction, the sinusoidal electric
field at z=50cm is delayed relative to the fields at z=75cm.
Calculate the time delay and the phase delay.
Calculate the average power density in the wave if the peak
value of the magnetic field is 0.4A/m.
08
Give a brief note on matched loads. 06
Q.5 Derive an expression for wave propagation in a perfect insulators. 10
Explain lossy-line attenuator in a co-axial line. 04
Q.6 Sketch and explain standard coaxial connectors. 10
What is a Gunn effect? 04
Q.7 With a neat circuit diagram and relevant equations, explain the
velocity modulation process in a two cavity klystron.
10
Write a short note on Microwave spectrum. 04