APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
BTECH DEGREE VI™ SEMESTER MODEL EXAMINATION MARCH 2018
EC306 ANTENNA AND WAVE PROPAGATION

Max time: 3 Hrs Max Marks: 100 Marks

PART A (Answer any two from the following)

1. a) Derive the expression for effective aperture of an antenna. (6M)
b) Define directivity gain of an antenna. (2M)
c) Derive the expression for retarded potential of short dipole (7M)

2. a) Explain (i) radiation resistance

(ii) antenna beam width (7M)

b) Derive the expression for power of halfwave dipole (8M)
3. a) State and prove the principle of reciprocity (5M)
b) What is power gain of an antenna (3M)
c) Derive the expression for radiation resistance of short dipole (7M)

PART B (Answer any two from the following)

4. a) ) Derive an expression for the field of array of two point sources with equal amplitude and

phase. (7M) b) Write short note on
(i)Travelling wave antenna (4M)
(ii)V Antenna (4M)

5. a) Design the array of n isotropic sources of equal amplitude and spacing(broadside case). (7M) b)
Design a rhombic antenna. (8M)
6. a) Derive the conditions for design a Dolphchebyshev array. (8M)

b) Explain the principle and application of Horn antenna. (6M)