Total marks: --
Total time: --
INSTRUCTIONS
(1) Assume appropriate data and state your reasons
(2) Marks are given to the right of every question
(3) Draw neat diagrams wherever necessary


1 (a) Derive:
1) Voltage and current equations on a transmission line.
2) The Characteristic impedance of the line.
3) Propagation constant.
4) Phase velocity.
5) The relative phase velocity factor.
12 M
1 (b) What is impedance matching? Explain single stub matching and double stub matching.
8 M

2 (a) Derive TEmn field equation in rectangular waveguide and define cut off wave number, cut-off frequency, propagation constant, phase velocity, character wave impedance and wave length in the guide.
10 M
2 (b) Explain why TEM mode is not possible in waveguides.
2 M
2 (c) Explain faraday rotation and discuss microwave circulator.
8 M

3 (a) Discuss the criterion for classifying the modes of operation for Gunn effect diodes. For a transit time domain made; the domain velocity is equal to the current drift velocity is 107 cm/s. Determine the drift length of the diode of a frequency of 8GHz
7 M
3 (b) Explain how carrier current I0(t) and external current Ie(t) are generated when a read diode is mounted in a microwave resonant circuit, with the aid of diagrams for structure of read diode, field distribution, applied ac voltage and I0 (t) and Ie(t).
7 M
3 (c) Write equivalent circuit for a parametric amplifier. AN up-converter parametric amplifier has the following parameters:
i) Figure of merit; γQ=8
ii) Ratio of output frequency over signal frequency f0/fδ
iii) Factor of merit figure;γ=0.2
iv) Diode temperature Td=300°t.
Calculate : i) The power gain in dB; ii) The noise figure in dB; iii) Bandwidth.
6 M

4 (a) What is a reciprocal network? For a reciprocal microwave N-port network prove that the admittance and impedance matrices are symmetrical.
7 M
4 (b) State and prove the following properties of S-parameters
i) Symmetry property for a reciprocal network.
ii) Unitary property for a lossless junction.
8 M
4 (c) The impedance matric of a passive network is given by \[Z=\begin{bmatrix} 4 &3 \\1 &2 \end{bmatrix}\], find scattering matrix.
5 M

5 (a) Why are co-axial connectors and adaptors used? List six types of co-axial connectors with their frequency ranges.
5 M
5 (b) What are waveguide tees? Explain with the aid of neat diagram, E-plane tree and H-plane tree.
9 M
5 (c) List four applications of Magic T. Explain Magic-Tee as a microwave mixer.
6 M

6 (a) Show that for a micro trip line, the quantity factors is Qc\[Q_{c}=0.636\sqrt[h]{\sigma f_{CH_{2}}}\].
7 M
6 (b) A gold parallel strip line has the following parameters
Relative dielectric constant of polyethylene εrd2.25.
Strip width; W=25mm
Separation width; d=5mm
Calculate:
i) Characteristic impedance of the strip line
ii) Strip-line capacitance
iii) Strip-line inductance
iv) Phase velocity.
8 M
6 (c) Write a note on coplanar stripline.
5 M

7 (a) What is radar? With a neat block diagram explain the operation of radar.
8 M
7 (b) Explain the various forms of radar equation.
6 M
7 (c) Discuss the application the radar.
6 M

8 (a) With a neat block diagram, explain CW Doppler radar.
8 M
8 (b) Explain a simple MTI delay line canceller.
8 M
8 (c) Discuss the difference between MTI and Doppler radar.
4 M



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