Microwave And Radar Model Question Paper-2

B.E Fifth Semester  Examination, Dec-10/Jan-11

Model Set-2

Microwave and Radar

1        a. Define and derive expressions for attenuation and phase constant, wavelength and velocity of propagation in a transmission line.              (8 Marks)

b. Discuss applications and properties of smith chart.            (5 Marks)

c. In a smith chart, plot the following impedances

            i) 0.4-j3.8         ii) 1.6+j2.4       iii) 2.4-j0.75                 (7 Marks)

2    a. Draw a neat diagram of a H-plane Tee junction and explain its operation. Write its [S] matrix.                                                                     (8 Marks)

      b. With a neat diagram explain the operation of a 3-port circulator.

                                                                                                      (6 Marks)

      c. Calculate the resonant frequency of a rectangular resonator of dimensions a=3cm, b=2cm, d=4cm, when the mode of operations is TE₁₀₁.   (6 Marks)

3        a. With neat diagrams explain the construction and operation of READ diode.

(8 Marks)

            b. Draw the equivalent circuit for parametric amplifier and explain.

                                                                                                            (5 Marks)

            c. An IMPATT diode has a drift length of 2.5µm. If the basic semi-conductor material is Silicon for which the drift velocity is 5 x 10⁶ cm/sec, determine (a) the drift time of the carriers         (b) the nominal frequency of the IMPATT diode.

                                                                                                            (7 Marks)

4    a. Give the relation of Z, Y and ABCD parameters with S-parameters.

                                                                                                      (8 Marks)

      b. Explain the Phase shift Properties.                                     (4 Marks)

      c. Explain the symmetrical Z and Y matrices for reciprocal network.

                                                                                                      (8 Marks)

5    a. Explain with neat diagram the construction and operation of a precision rotatory phase shifter.                                                        (8 Marks)

      b. Explain with neat sketches the construction and operation of a Magic Tee junction. List the characteristics and hence derive the s-matrix of a Magic Tee junction.                                                                                       (12 Marks)

6        a. With a neat diagram explain the construction and operation of a microstrip line.

(8 marks)

            b. Give a brief account of attenuation losses in parallel strip line.

                                                                                                            (8 marks)

            c. Explain the advantages and disadvantages of Plannar transmission lines over Co-axial line.                                                                                            (4 marks)

7    a. Briefly discuss the origins of Radar.                                   (8 Marks)

      b. With a neat block diagram explain the operation of a Radar.        (7 Marks)

      c. A marine Radar operating at 10GHz as a maximum range of 50KM with an antenna gain of 4000. a transmitter as a power of 250KW and minimum detectable signal of 10^-11W. Determine the cross section of the target the Radar can sigh.

                                                                                                      (5 Marks)

8    a. Explain the principle and working of MTI radar with the help of block diagram.

                                                                                                      (8 Marks)

      b. Write brief notes on-

                  i) Blind speed 

                  ii) 3-pulse cancellor

                  iii) Applications of Radar                                           (4x3=12 Marks)