Frequently Asked Questions On Antenna Theory With Answers - 9.


This page contains basic questions and short notes on some of the keywords on antenna theory:


41) What is meant by similar Point sources?

Whenever the variation of the amplitude and the phase of the field with respect to the absolute angle for any two sources are same then they are called similar point sources.

The maximum amplitudes of the individual sources may be unequal.


42) What is meant by identical Point sources?

Similar point sources with equal maximum amplitudes are called identical point sources.


43) What is the principle of the pattern multiplication?

The total field pattern of an array of non isotropic but similar sources is the product of the

  • Individual source pattern and
  • The array pattern of isotropic point sources each located at the phase center of the individual
  • source having the same amplitude and phase.


While the total phase pattern is the sum of the phase patterns of the individual source pattern and array pattern.


44) What is the advantage of pattern multiplication?

  • Useful tool in designing antenna.
  • It approximates the pattern of a complicated array without making lengthy computations.


45) What is tapering of arrays?

Tapering of array is a technique used for reduction of unwanted side lobes. The amplitude of currents in the linear array source is non-uniform; hence the central source radiates more energy than the ends. Tapering is done from center to end.


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