AWP (B-TECH Electronics and Communication Engineering 5th)

1. Introduction:

Physical concept of Radiation in single wire, two wire, and dipole, Current

Distribution on a thin wire antenna.

2. Fundamental Parameters of Antenna:

 Radiation Pattern, Radiation Power Density,

Radiation intensity, Directivity, Gain, Antenna efficiency, Beamwidth, Bandwidth,

Polarisation, Antenna Input Impedance, Elementary idea about self and mutual

impedance, Radiation efficiency, Effective aperture, Antenna Temperature.

3. Linear Wire Antennas:

 Retarded potential, Infinitesimal dipole, Current distribution of

short dipole and half wave dipole, Far-field, Radiating near-field and reactive near-field

region, Monopole and Half wave dipole.

4. Antenna Arrays:

 Array of two point sources, Array factor, n-element linear array with

uniform amplitude and spacing, Analysis of Broadside array, Ordinary end-fire array,

Hansen-woodyard end fire array, n-element linear array with non-uniform spacing, ,

Analysis of Binomial and Dolph-Tschebyscheff array, Scanning Array, Superdirective

array.

5. Aperture Antennas:

 Field Equivalence principle, Rectangular and circular aperture

antennas, Horn antenna, Babinet’s Principle, Slot Antenna, Reflector antenna.

6. Ground wave Propagation:

 Friis Free space equation, ,Reflection from earth’s

surface, Surface and Space wave propagation for vertical and horizontal dipole, Field

strength of Space wave, Range of space wave propagation, Effective earth’s radius,

Effect of earth imperfections and atmosphere on space wave propagation, Modified

refractive index, Duct propagation, Tropospheric propagation.

7. Ionospheric Propagation:

 Structure of ionosphere, propagation of radio waves

through ionosphere, Refractive index of ionosphere, Reflection and refraction of waves

by ionosphere, Critical frequency, Maximum usable frequency, Optimum working

frequency, Lowest usable high frequency, virtual height, Skip Distance, Effect of earth’s

magnetic field.