UNIT - I Antenna Basics : Basic Antenna Parameters - Patterns, Beam Area, Radiation Intensity, Beam Efficiency, Directivity-Gain-Resolution, Antenna Apertures, Effective Height. Fields from Oscillating Dipole, Field Zones, Front - to - back Ratio, Antenna Theorems, Radiation, Retarded Potentials - Helmholtz Theorem. Thin Linear Wire Antennas - Radiation from Small Electric Dipole, Quarter Wave Monopole and Half Wave Dipole - Current Distributions, Field Components, Radiated Power, Radiation Resistance, Beam Width, Directivity, Effective Area and Effective Height, Natural Current Distributions, Far Fields and Patterns of Thin Linear Centre-fed Antennas of Different Lengths. Loop Antennas - Small Loop, Comparison of Far Fields of Small Loop and Short Dipole, Radiation Resistances and Directivities of Small Loops (Qualitative Treatment). (Chapter - 1) UNIT - II Antenna Arrays : 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, BSAs with Non-uniform Amplitude Distributions - General Considerations and Binomial Arrays. Antenna Measurements : Introduction, Concepts - Reciprocity, Near and Far Fields, Coordinate System, Sources of Errors. Patterns to be Measured, Directivity Measurement, Gain Measurements (by Comparison, Absolute and 3-Antenna Methods) (Chapter - 2) UNIT - III VHF, UHF and Microwave Antennas - I : Arrays with Parasitic Elements, Yagi-Uda Array, Folded Dipoles and 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. (Chapter - 3) UNIT - IV VHF, UHF and Microwave Antennas - II : UNIT - V Wave Propagation
