STUPIDSID
1 (a)
Describe the importance of the 'S' parameters in microwave.
5 M
1 (b)
Write applications of 'Microwaves'.
5 M
1 (c)
Compare 'Travelling Wave Tube' with 'Klystron'.
5 M
1 (d)
How are waveguides different from the normal two wire transmission lines? Discuss the similarities and dissimilarities.
5 M
2 (a)
Justify: 'TEM mode does not exist in hollow waveguide'.
5 M
2 (b)
Starting with Maxwell's equations, derive the expression of TEmm wave in rectangular waveguide.
10 M
2 (c)
What are 'O' and 'M' types of tubes in the microwaves.
5 M
3 (a)
Draw a neat diagram of Two Cavity Klystron Amplifier. Explain with diagram, its bunching process. Derive the equation of its velocity modulation.
10 M
3 (b)
Explain the working of 'Gyrator' with its neat diagram.
5 M
3 (c)
An air-filled circular waveguide with radius of 5 cm, operating at TE11 mode,
i) Determine the cut-off frequency
ii) Determine the guide wavelength for the operating frequency of 3 Ghz.
iii) Determine the wave impedance in the guide.
i) Determine the cut-off frequency
ii) Determine the guide wavelength for the operating frequency of 3 Ghz.
iii) Determine the wave impedance in the guide.
5 M
4 (a)
Draw and explain 'Two-Hole Directional Coupler'.
Define:
i) Coupling Factor
ii) Directivity
iii) Isolation
Also, Derive the S-Matrix for the same.
Define:
i) Coupling Factor
ii) Directivity
iii) Isolation
Also, Derive the S-Matrix for the same.
10 M
4 (b)
Why 'Hybrid Tee' is called as 'Magic Tee'. Derive S-Matrix for EH plane Tee.
5 M
4 (c)
Explain with neat diagram, working of 'Microwave Transistor'.
5 M
5 (a)
Explain the set up for VSWR measurement in microwaves.
10 M
5 (b)
Justify: Wavelength is a High Pass Filter'.
5 M
5 (c)
A Reflex Klystron Operates under the following conditions:
Vo=600 V, L=1mm
ii) Rsh=15 KΩ, fr=9 Ghz
The tube is oscillating at 'fr' at the peak of the n=2 mode. Assume that the transit time through the gap and beam loading can be neglected.
i) Find the value of repeller voltage.
ii) Find the direct current necessary to give a microwave gap voltage of 200 Volts.
iii) What is the electronic efficiency under this conditions.
Vo=600 V, L=1mm
ii) Rsh=15 KΩ, fr=9 Ghz
The tube is oscillating at 'fr' at the peak of the n=2 mode. Assume that the transit time through the gap and beam loading can be neglected.
i) Find the value of repeller voltage.
ii) Find the direct current necessary to give a microwave gap voltage of 200 Volts.
iii) What is the electronic efficiency under this conditions.
5 M
6 (a)
Explain with neat diagram, principle of working of 'Rectangular Cavity Resonator'. Also obtain the expression for its resonance frequency.
10 M
6 (b)
Explain following terms:-
i) Cut -off frequency
ii) Dominant Mode
iii) Phase Velocity
iv) Group Velocity
v) Degenerate Mode.
i) Cut -off frequency
ii) Dominant Mode
iii) Phase Velocity
iv) Group Velocity
v) Degenerate Mode.
5 M
6 (c)
An IMPATT diode has following parameters carrier drift velocity vd=2×107 cm/s.
Drift region length L=6μm.
Maximum operating voltage VOmax=100 Volts
Maximum operating current IOmax=200 mAmp.
Efficiency Kη=15%
Breakdown voltage Vbd=90 Volt.
Find:
i) The maximum power in watt.
ii) The resonant frequency.
Drift region length L=6μm.
Maximum operating voltage VOmax=100 Volts
Maximum operating current IOmax=200 mAmp.
Efficiency Kη=15%
Breakdown voltage Vbd=90 Volt.
Find:
i) The maximum power in watt.
ii) The resonant frequency.
5 M
Write short notes on any four of the following:
7 (a)
Two Valley Model Theory
5 M
7 (b)
Strip Lines
5 M
7 (c)
Apple-gate Diagram of Reflex Klystron
5 M
7 (d)
Slow wave structures
5 M
7 (e)
Limitations of conventional vacuum tubes at microwave frequency.
5 M
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