Lecture Notes Antenna & Wave Propagation
JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY ANANTAPUR
B.Tech. III - I Sem (13A04501) ANTENNAS & WAVE PROPAGATION
To introduce the fundamental principles of antenna theory and various types of antennas.
Applying the principles of antennas to the analysis, design, and measurements of antennas.
To know the applications of some basic and practical configurations such as dipoles, loops,
and broadband, aperture type and horn antennas.
Through lecture, and out-of-class assignments, students are provided learning experiences that enable them to:
Understand the basic principles of all types of antennas and
Analyze different types of antennas designed for various frequency ranges.
Become proficient with analytical skills for understanding practical antennas.
Design some practical antennas such as dipole, Yagi - uda, and horn antennas.
Determine the radiation patterns (in principal planes) of antennas through measurement setups.
Develop technical & writing skills important for effective communication.
g) Acquire team-work skills for working effectively in groups.
UNIT I : Antenna Basics & Dipole antennas: Introduction, Basic antenna parameters- patterns, Beam
Area, Radiation Intensity, Beam Efficiency, Directivity-Gain-Resolution, Antenna Apertures, Effective
height, Fields from oscillating dipole, Field Zones, Shape-Impedance considerations, Polarization –
Linear, Elliptical, & Circular polarizations, Antenna temperature, Antenna impedance, Front–to-back
ratio, Antenna theorems, Radiation – Basic Maxwell‘s equations, Retarded potential-Helmholtz Theorem,
Radiation from Small Electric Dipole, Quarter wave Monopole and Half wave Dipole – Current
Distributions, Field Components, Radiated power, Radiation Resistance, Beam width, Natural current
distributions, far fields and patterns of Thin Linear Center-fed Antennas of different lengths, Illustrative
UNIT II : VHF, UHF and Microwave Antennas - I: Loop Antennas - Introduction, Small Loop,
Comparison of far fields of small loop and short dipole, Radiation Resistances and Directives of small
and large loops (Qualitative Treatment), Arrays with Parasitic Elements - Yagi - Uda Arrays, Folded
Dipoles & their characteristics. Helical Antennas-Helical Geometry, Helix modes, Practical Design
considerations for Monofilar Helical Antenna in Axial and Normal Modes. Horn Antennas- Types,
Fermat‘s Principle, Optimum Horns, Design considerations of Pyramidal Horns, Illustrative Problems.
UNIT III :VHF, UHF and Microwave Antennas - II: Micro strip Antennas- Introduction, features,
advantages and limitations, Rectangular patch antennas- Geometry and parameters, characteristics of
Micro strip antennas, Impact of different parameters on characteristics, reflector antennas - Introduction,
Flat sheet and corner reflectors, parabola reflectors- geometry, pattern characteristics, Feed Methods,
Reflector Types - Related Features, Lens Antennas - Geometry of Non-metallic Dielectric Lenses, Zoning
, Tolerances, Applications, Illustrative Problems.
UNIT IV : Antenna Arrays & Measurements: Point sources - Definition, Patterns, arrays of 2 Isotropic
sources- Different cases, Principle of Pattern Multiplication, Uniform Linear Arrays – Broadside Arrays,
Endfire Arrays, EFA with Increased Directivity, Derivation of their characteristics and comparison, BSAa
Dept. of ECE