Chapter -1 Introduction
to Microwaves:
1.
What is the importance of Microwave? Give its applications.
Chapter -2 Microwave
transmission lines and waveguides:
1. Derive
necessary equations for attenuation constant and phase constant with reference to
EM wave propagating along transmission line.
2.
Draw an equivalent circuit of two
wire parallel transmission line having length of Dz and derive
the equations for it.
3.
What is impedance matching? Explain
impedance matching using stub.
4.
Explain in brief standing wave and
reflection coefficient of transmission line and
derive the expression for the impedance and reflection coefficient at any point
on the line.
5.
Derive the equations of
characteristic and Input impedance of tow wire transmission line.
6.
Sketch circular and
rectangular waveguide and compare their dominant mode, advantages and
disadvantages.
7.
Difference between Strip line and
Micro Strip line, with advantages and disadvantages.
8. Explain Cutoff Wavelength of rectangular waveguide and give
the relation between l0,
lg, lc.
9. Define:
1. Group
velocity.
2. Phase
velocity.
3. VSWR.
10.Short
note with Advantages and Disadvantages.
1. Coplanar line.
2. Slot line.
3.
l/4 and l/2 TX lines
11.
Why TE10 is the dominant
mode for rectangular waveguide?
12.
Why TEM wave cannot propagate through
rectangular waveguide?
13.
Draw the field pattern of TE01, TE10,
TE11, TE20, TM11 for rectangular waveguide.
14.
What are the losses due to mismatch
in transmission lines
Chapter – 3 Microwave component & their S-parameters :
1.
Short note on “S” parameters
2.
What do you mean by reciprocal
network? Draw and explain series tee junction and find its
simplified S-matrix using S-parameter.
3.
What is magic associate with magic
tee junction?
4.
Explain the operation of Magic TEE with its
s-parameter. Also list some applications of magic TEE. Draw and explain
waveguide band, corners and twist in detail with their applications.
5.
Explain faraday’s rotation effect. Describe the
construction and working of microwave isolator. Explain the terms isolation and
insertion loss as related to isolator.
6.
What is the purpose of directional Coupler? Define
coupling factor, directivity, isolation of Directional coupler and write
expression for each.
7.
Draw schematic of four port circulator and explain its
working, also show and explain how one can construct a four port circulator
using two magic tees and a phase shifter.
Chapter – 4 Microwave
tubes and circuits:
1.
What are the limitations of
conventional tubes at high frequencies list that and explain any four.
2.
Describe the construction and working,
applications and performance characteristics of a reflex klystron. Explain how
velocity and current modulation takes place using
the Applegate diagram.
3.
Give difference between two cavity
klystron and reflex klystron. Also draw the schematic of two cavity klystron.
And explain its working, performance and applications.
4.
Draw different slow wave structures
and write why slow wave structures are used in traveling wave tubes? Also
explain working and applications of TWT with neat sketch.
5.
Explain the mechanism of oscillations
of Magnetron Oscillator with the aid of suitable diagram and discuss its
performance characteristics.
Chapter -5 Semiconductor microwave devices and
circuits:
1.
Explain IMPATT Diode with its construction, working
and application.
2.
Explain the Tunnel diode characteristics with the aid
of Energy band diagram.
3.
Why Gun diode can’t be called a diode justifies;
Explain Gunn effect using two valley theory.
4.
Give at least three differences between microwave
transistor and TEDs (i.e. transfer electron devices). Write the statement of
Gunn effect and explain GaAs diode.
5.
Explain figure of merit of various surface geometries
of microwave bipolar transistor.
6.
Explain PIN diode and its applications.
7.
Explain construction and working of varactor diode.
And also explain quality factors for same.
8.
Short note on:
A.
Parametric amplifier
B.
IMPATT and TRAPATT diode
Chapter – 6 Radar
Systems:
1.
Explain the
principal of RADAR. Derive the range equation of RADAR. Briefly discuss the
factors which influence the range of radar.
2.
Explain advantages
of RADAR. Give its applications.
3.
Short note on MTI
RADAR.
4.
Explain Pulse
RADAR.
5.
Explain Scanning
and tracking.
6.
Short note on
display of radar.
7.
What is Doppler
radar? Explain CW radar and compare with FM CW radar
EXAMPLES
asked in GTU Exams:
1.
The dimension of a waveguide is
2.5X1cms.The frequency is 8.6 GHz Find the possible
modes that can propagate through the waveguide also find the cutoff frequencies
for the same.
2.
A rectangular waveguide is filled by
dielectric material of Er =9, with
inside dimension of 7X3.5cm. It operates in
the dominant TE10 mode. Determine (i) cut off frequency (ii) phase
velocity at a frequency of 2 GHz (iii) guided wavelength at the same frequency.
3.
A typical transmission line has a
resistance of 6 W /km,
inductance of 2.2mH/km, a capacitance of 0.005 nF/km and a
conductance of 0.05mmho/km. Calculate the characteristic impedance,
attenuation constant and phase constant of the transmission line at a frequency
of 1kHz.Alo calculate the phase velocity of the signal
4.
A rectangular waveguide has dimension
of 2.29 cm and 1.02 cm. It is desired that this
waveguide is to be operated only in dominant mode and operating frequency is at
least 25% above cut off frequency of dominant mode and not higher than 95% of
the next cut off frequency. What is allowable operating frequency?
5.
A 5.2 cm length of lossless 200 W line is
terminated in a load impedance of 60 + j 100 W Using smith chart
(i)
Determine Reflection coefficient
and SWR along the line.
(ii)
Determine the Z and Y at the input and at a point 2.0
cm from the load end. The signal frequency is 750 MHz and l = l0
