WITH EFFECT FROM THE ACADEMIC YEAR 2016 - 2017
EC353
ANTENNAS AND WAVE PROPAGATION
Instructions 4 Periods per week
Duration of University Examination 3 Hours
University Examination 75 Marks
- 25 Marks
Unit-I
Principles of radiation retarded potential and isotropic radiator, Antenna parameters: Radiation pattern, radiation intensity, Antenna temperature. far field, near field, Gain, directivity, Antenna Polarization, effective aperture and aperture efficiency Point sources, Current distribution, infinitesimal dipole.
Unit-II
Half-wave dipole, quarter wave monopole, Effect of earth on Vertical patterns, Loop antenna, far field pattern of circular loop with uniform current. Helical antennas: Axial mode pattern, wideband characteristics, radiation efficiency.
Unit-III
VHF, UHF turnstile antennas, Rhombic Antenna, Yagi – Uda Antenna, Log periodic Antenna, Horn Antenna, Parabolic Reflector, Lens antenna, Microstrip antennas: different types, advantages and disadvantages of Microstrip antennas (Working principle and characteristics only). Antenna Measurements: Antenna test site, impedance, radiation pattern and gain measurement techniques.
Unit-IV
Arrays of point sources, two element array with equal and unequal amplitudes, different phases. Linear n- element array with uniform distribution, Broadside and End fire arrays, Binomial array, principle of pattern multiplication. Effect of inter element phase shift on beam scanning.
Unit-V
Ground wave propagation, Space and Surface waves, Troposphere refraction and reflection, Duct propagation, sky wave propagation, Regular and irregular variations in ionosphere. Friis transmission formula, Line of sight propagation.
Suggested Reading:
- 1.John D. Krauss, Ronald J. Marhefka & Ahmad S. Khan, “Antennas and wave Propagation”, 4/e TMH, 2010.
- 2.Constantine A. Balanis, Antenna Theory: “Analysis and Design, “3/e, John Wiley, 2005.
- 3.Edward C. Jordan and Kenneth G. Balmain, “Electromagnetic waves and Radiating Systems”, 2/e PHI 2001.
- 4.A.R. Harish, M. Sachidananda, “Antennas and Wave Propagation”, 2/e, Oxford University Press, 2016.
- 5.Chatterjee, R., “Antenna Theory and Practice“, New Age Publishers, 2008