ECL405 Waveguides and Antennas [(3-0-0); Credits: 3]
Course Outcomes
Students will
1. Be able to understand and analyse guided wave propagation.
2. Be able to analyze and design transmission line based systems and components.
3. Be familiar with radiation theory, antenna theory and terminology.
4. Be able to achieve proficiency of antenna array analysis and design.
5. Be conversant with various types of antennas and related technologies for different applications.
Contents
Revision of Maxwell’s equations for time varying fields and physical significance of Curl, Divergence and Gradient. Waves between parallel planes, TE, TM,& TEM and their characteristics. Attenuation in parallel plane guides wave impedances. TE, TM waves and impossibility of TEM mode in Rectangular waveguide. Different characteristics like group velocity, phase velocity, guide wavelength and wave impedances.
Transmission line equations and their solutions. Transmission line parameters, Characteristic impedances, Propagation constant, Attenuation constant, Phase constant, Waveform distortion, Distortion less transmission lines, Loading of transmission lines, Reflection coefficient and VSWR. Equivalent circuits of transmission lines, Transmission lines at radio frequency. Open circuited and Short circuited lines, Smith Chart, Stub matching.
Scalar and vector potentials related potentials, field due to a current element, power radiated and radiation resistance for field due to a dipole, power radiated and radiated resistance. Reciprocity theorem applied to antennas. Antenna terminology: Gain, Aperture, Radiation intensity, Directivity, Directive gain, Beam width, Radiation patterns, FBR, Antenna bandwidth etc.
Concept of antenna arrays, Two element arrays and their directional characteristics, Linear array analysis, Broadside and end fire arrays, Principles of pattern multiplication & their application. Polynomial representation, Binomial arrays, Design of broadcast array for a specific pattern, Chebyshev array synthesis.
Analysis of power patterns of various antennas like Parabolic reflectors, Lens antenna, folded dipole, Turnstile antenna, Yagi antenna, Log-periodic antenna, Horn antenna & feeding, Traveling wave antenna, Printed antennas, Case grain antenna, Patch & Micro strip antennas, Superconducting antenna, Rhombic, Helical, Open ended waveguide radiator, Small design problems & applications.
Signal processing antennas or smart antenna, DOA, Principle beam formation & Digital beam formatting, Switched beam systems, Adaptive antennas, introduction to concepts of various signal processing algorithms, Principle of special filtering, Antenna diversity, TRB, SRB and Nulling of interference. Introduction to antenna measurement methods: measurement of Gain, Radiation pattern, Time domain gating, Antenna noise temperature & G/T, Impedance & Bandwidth. Introduction to measurement of cellular radio handset antenna.
Text Books
1. K.D.Prasad, “Antennas and Wave Propagation”, Khanna or Satya Publications
2. Jhordan & Balmin, “Electromagneting waves and radiating systems”, Pearson
Reference Books
1. Raju, “Electromagnetic field theory and transmission lines”, Pearson
2. Raju, “Antennas and wave propagation”, Pearson
3. Kraus, “Antennas for all applications”, TMH
4. Sadiku, “Elements of electromagnetism”, Oxford
5. Shevgaonkar, “Electromagnetic Waves” TMH