Antennas and Propagation

For a short dipole of /15 long and loss resistance of 1 Find:

i) Efficiency 

Write short note on:

ii) Corner reflector antenna

Write short note on:

i) Yagi-Uda antenna 

Explain the practical design considerations for the axial mode helical antennas.

With relevant sketches, explain the principle of Babinet's principle for complementary linear antennas. 

Explain patch or microstrip antennas with necessary sketch.

Derive the far field expressions for small loop antenna.

Write short note on:

iii) Rhombic antenna

Write short note on:

ii) Folded dipole antennas

For a short dipole of /15 long and loss resistance of 1 Find:

iii) Effective aperture

For a short dipole of /15 long and loss resistance of 1 Find:

ii) Radiation resistance

Explain term as related to antenna systems:

i) Beam area 

Derive the far field components of short dipole.

Explain the principle of pattern multiplication with an example.

Complete the field patterns and find BWFN and HPBW for an array of 4 point sources spaced /6 distance apart. They have a phase difference of /3 between adjacent elements.

Derive an expression for array factor and relative field of linear array of 'n' isotropic point sources of equal magnitude and spacing.

An antenna has a field pattern given by  Find half power beam width (HPBW) and beam width between first nulls (BWFN). 

Find the directivity of the power pattern given by 

Explain term as related to antenna systems:

v) Radiation resistance

Explain term as related to antenna systems:

iv) Effective aperture

Explain term as related to antenna systems:

ii) Power gain

Explain term as related to antenna systems:

ii) Directivity