JNTU Kakinada B-Tech 3-1 RT31045 I ANTENNAS AND WAVE PROPAGATION R13 April 2018 Question Paper

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Code No: RT31045
III B. Tech I Semester Supplementary Examinations, May – 2018
ANTENNAS AND WAVE PROPAGATION (Electronics and Communication Engineering)Time: 3 hours Max. Marks: 70
Note: 1. Question Paper consists of two parts (Part-A and Part-B)2. Answering the question in Part-A is compulsory
3. Answer any THREE Questions from Part-B
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
PART ?A
1 a) Define radiation intensity, directivity, and solid angle? [3M]
b) Calculate the directivity of an antenna ,if HPBW on one plane is 30
o
and 60
o
on orthogonal plane?
[4M]
c) Define Broadside, end fire and scanned array antennas? [4M]
d) List out the advantages and limitations of micro strip antennas? [4M]
e) Calculate the far-field distance between transmitting and test antenna of
Da=2?.
[4M]
f) If the critical frequency of ionized layer is 2 MHz, find the electron density
of the Layer?
[3M]
PART -B
2 Explain the terms polar and rectangular radiation patterns, Resolution and
effective height?
[16M]
3 a) Derive the radiation fields from small electric dipole at far field? [8M]
b) Explain radiation, induction and electrostatic fields? [8M]
4 a) Calculate and draw the radiation pattern of 2-element array, d=?/2, a
e
=0
o
. [8M]
b) By using pattern multiplication technique, Estimate the radiation pattern of N=3
element, d=?/2 of binomial array Antenna?
[8M]
5 a) Define axial ratio? Classify the polarization based on axial ratio? [8M]
b) Estimate the ?
max
, R
rad
of a long wire antenna whose length is 5??
[8M]
6 Explain in detail the function and design of a horn antenna?
[16M]
7 a) Derive the field strength equation in a space wave propagation? [8M]
b) Ex plain wave tilt effect in ground wave propagation? [8M]
*****
R13
SET – 1