JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD
JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B. Tech III ANTENNAS AND WAVE PROPAGATION Previous Question Paper (July - 2023 - R16)
Note: i) Question paper consists of Part A, Part B.
ii) Part A is compulsory, which carries 25 marks. In Part A, Answer all questions.
iii) In Part B, Answer any one question from each unit. Each question carries 10 marks and may have a, b as sub questions.
PART - A
Define the term half-power beam width of an antenna.
Answer
The Half-Power Beam Width (HPBW) is the angular separation between the two points on the radiation pattern where the radiated power density is one-half of the maximum value of the main beam.
Calculate the radiation efficiency of a short dipole which is λ/15 m long and it has Rloss=1.5Ω.
Answer
For a short dipole of length L = λ/15, the radiation resistance is given by:
The radiation efficiency η is calculated as:
List the applications of helical antenna.
Answer
Sign in to view the complete answer paper.
Classify and draw the horn antenna structure.
Answer
Sign in to view the complete answer paper.
Write the characteristics of microstrip antennas.
Answer
Sign in to view the complete answer paper.
Explain the need of Reflector antenna. Is it Preferable at low Frequencies?
Answer
Sign in to view the complete answer paper.
What is the need for the Binomial array?
Answer
Sign in to view the complete answer paper.
Define uniform and Non uniform linear array.
Answer
Sign in to view the complete answer paper.
What are the types of wave propagation?
Answer
Sign in to view the complete answer paper.
Define path loss in FRIIS Transmission formula.
Answer
Sign in to view the complete answer paper.
PART - B
Derive the field equations from a small loop antenna.
Answer
Sign in to view the complete answer paper.
Explain effective aperture area with its types in detail.
Answer
Sign in to view the complete answer paper.
What is a folded dipole antenna? Derive the input impedance of folded dipole antenna and what are the applications of it.
Answer
Sign in to view the complete answer paper.
Explain the working principle of a helical antenna in normal and axial modes.
Answer
Sign in to view the complete answer paper.
Design and explain the working principle of a microstrip antenna. Explain the effects of different types of its effective dielectric constant.
Answer
Sign in to view the complete answer paper.
Briefly explain about Flat Sheet Reflectors.
Answer
Sign in to view the complete answer paper.
Classify the array antenna based on amplitude distribution. Derive the Array factor of a 2-element linear antenna and α=0°.
Answer
Sign in to view the complete answer paper.
Explain principle of pattern multiplication with example.
Answer
Sign in to view the complete answer paper.
With a neat block diagram, explain the method of measurement of radiation pattern of an antenna.
Answer
Sign in to view the complete answer paper.
What are the different precautions take care while measuring antenna parameters?
Answer
Sign in to view the complete answer paper.
Discuss MUF and skip distance and also derive the relation between them.
Answer
Sign in to view the complete answer paper.
Prove that the virtual height is greater than physical height.
Answer
Sign in to view the complete answer paper.
Derive the Critical frequency Equation.
Answer
Sign in to view the complete answer paper.
Explain the concept of Duct propagation.
Answer
Sign in to view the complete answer paper.