ANTENNAS AND WAVE PROPAGATION

Credits	Periods			Exam Hrs.	Sessional Marks	Exam Marks	Total Marks
	Theory	Tutorial	Lab
4	3	1	-	3	30	70	100

1. Radiation and Antennas  
Antenna definition, Functions of antennas , Network theorems, Properties of
antennas, Antenna parameters , Polarization, Basic antenna elements , Radiation
mechanism, Radiation fields of alternating current element, Radiated power and
radiation resistance of current element, Radiation, induction and electrostatic fields,
Hertzian dipole, Different current distributions in linear antennas, Radiation from
half-wave dipole, Radiation from quarter wave monopole , Radiation characteristics
of dipoles.
2. Analysis of Linear Arrays
Directional characteristics of dipole antennas, Radiation pattern of alternating
current element, Radiation pattern expressions of centre-fed vertical dipoles of finite
length, Radiation patterns of centre-fed vertical dipoles, Radiation patterns of centrefed horizontal dipoles, Radiation patterns of vertical dipoles, Two-element uniform
array, Uniform linear arrays, Field strength of a uniform linear array, First sidelobe
ratio (SLR), Broadside and End-fire arrays, Patterns of array of non-isotropic
radiators, Multiplication of patterns, Generalized expression for principle of pattern
multiplication, Radiation pattern characteristics, Binomial arrays, Effect of earth on
vertical patterns, Effect of earth on radiation resistance, Methods of excitation,
Impedance matching techniques,  Transmission loss between transmitting and
receiving antennas - FRIIS formula, Antenna temperature and signal-to-noise ratio.
3. Array Synthesis  
Introduction, Synthesis methods, Fourier transform method, Linear array design by
Woodward-lawson method, Dolph-chebychev method (Tschebyscheff distribution),
Taylor method, Laplace transform method, Standard amplitude distributions.
4. HF, VHF and UHF Antennas 
Introduction, Isotropic radiators, Directional antennas, Omni-directional antennas,
Resonant antennas, Non-resonant antennas, LF antennas, Antennas for HF, VHF and
UHF, Dipole arrays, Folded dipole, V-Antennas, Inverted V-antennas, Rhombic
antenna, Yagi-Uda antenna, Log-periodic antennas, Loop antenna, Helical antenna,
Whip antenna, Ferrite rod antenna, Turnstile antennas, Discone antennas, Notch
antenna.

5. Microwave Antennas 
Introduction, Rod reflector, Plane reflector, Corner reflector, Parabolic reflector,
Types of parabolic reflectors, Feed systems for parabolic reflectors, Shaped beam
antennas, Horn antennas, Corrugated horns, Slot antennas, Impedance of a few
typical dipoles, Slots in the walls of rectangular waveguides, Babinet’s principle,
Lens antennas, Microstrip antennas.
6. Antenna Measurements  
Introduction, Drawbacks of measurements of antenna parameters, Methods to
overcome drawbacks in measurements, Methods for accurate measurements,
Measurement ranges, Indoor and outdoor ranges, Antenna impedance
measurements, Measurement of radiation resistance, Gain measurements,
Measurement of antenna bandwidth, Directivity measurement, Measurement of
sidelobe ratio, Measurement of radiation efficiency, Measurement of antenna
aperture efficiency, Measurement of polarization of antenna, Phase measurement.
7. Wave Propagation 
Propagation characteristics of EM Waves,  Factors involved in the propagation of
radio waves, Ground wave propagation, Ground wave field strength by Maxwell’s
equations, Reflection of radio waves by the surface of the earth, Roughness of earth,
Reflection factors of earth, Wave tilt  of the ground wave, Tropospheric wave
propagation, Atmospheric effects in space wave propagation,  Duct propagation,
Radio horizon, Troposcatter, Fading of EM waves in Troposphere, Line of sight
(LOS), Ionospheric propagation, Characteristics of ionosphere, Refractive index of
ionosphere, Phase and group velocities,  Mechanism of Ionospheric propagation,
reflection and refraction, Characteristic parameters of Ionospheric propagation, Sky
wave field strength, Fading and diversity  techniques, Faraday’s rotation, Effect of
earth’s magnetic field.

Text Book : 
1. Antennas and Wave Propagation, G.S.N. Raju, Pearson Education (Singapore)
Pvt., Ltd., New Delhi, 2007.
References :
1. EM Waves and Radiation Systems, E. C. Jordan and K. G. Balmain, PHI – N.
Delhi, 1997.
2. Antennas, J.D. Kraus, McGraw Hill, NY.
3. Antenna theory, C.A. Balanis, John Wiley & Sons, NY, 1982.