Antenna and Wave Propagation :-
- Unit - I :Antenna Principles
Potential Functions & Electromagnetic Field, Current Elements, Radiation from Monopole & Half Wave Dipole, power radiated by current element, radiation resistance.
Network TheoremsDirectional Properties of Dipole Antenna.
Antenna Gain, Effective Area, Antenna Terminal Impedance, Practical Antennas and Methods of Excitation, Antenna Temperature and Signal to Noise Ratio.
- Unit - II : Antennas Arrays
Two Element Array, Horizontal Patterns in Broadcast Arrays, Linear Arrays, Multiplication of patterns, effect of the earth on vertical patterns, Binomial array.
- Unit - III : Wave Propagation
Modes of Propagation, Plane Earth Reflection, Space wave and Surface Wave, Refelection and refraction waves by the Ionosphere Tropospheric Wave.
Ionosphere Wave Propagation in the Ionosphere, Virtual Height, MUF Critical frequency, Skip Distance, Duct Propagation, Space wave
- Unit - IV :
Practical antennas:VLF and LF transmitting antennas, effect of antenna height,Field of short dipole, electric field of small loop antenna, Directivity of circular loop antenna with uniform current, Yagi-Uda array: Square corner yagi-uda hybride, circular polarizationRhombic Antenna: Weight and Leg lengthParabolic Reflectors: Properties, Comparison with corner reflectorsHorn Antenna: Length and Aperture.Introduction to Turstile AntennaEffect of ground on antenna performance.Broadband Antenna: Frequency independent concept, RUMSEY’s Principle, Frequency independent planar log spiral antenna, Frequency independent conical spiral Antenna.
- Unit - V :
Antenna Measurements: Radiation Pattern measurement, Distance requirement for uniform phase, uniform field amplitude requirement, Introduction to phase measurement; Gain Measurement: Comparison method, Near field method, Introduction to current distribution measurement, Measurement of antenna efficiency, measurement of Noise figure and noise temperature of an antenna polarization measurement.