Antenna Theory - FAQ's With Answers - 3.


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


11) What is meant by Polarization?

The polarization of the radio wave can be defined by direction in which the electric vector E is aligned during the passage of atleast one full cycle.Also polarization can also be defined the physical orientation of the radiated electromagnetic waves in space. The polarization are three types. They are Elliptical polarization ,circular polarization and linear polarization.


12) What is meant by front to back ratio?

It is defined as the ratio of the power radiated in desired direction to the power radiated in the opposite direction. i.e FBR = Power radiated in desired direction / power radiated in the opposite direction.


13) Define antenna efficiency?

The efficiency of an antenna is defined as the ratio of power radiated to the total input power supplied to the antenna. Antenna efficiency = Power radiated / Total input Power


14) What is radiation resistance ?

The antenna is a radiating device in which power is radiated into space in the form of electromagnetic wave. W’ = I2 R Rr = W’/ I2 Where Rr is a fictitious resistance called called as radiation resistance.


15) What is meant by antenna beam width?

Antenna beamwidth is a measure of directivity of an antenna. Antenna beam width is an angular width in degrees, measured on the radiation pattern (major lobe) between points where the radiated power has fallen to half its maximum value. This is called as "beam width" between half power points or half power beam width.(HPBW).


ALSO READ: 

- What is Polarization & What Are It's Different Types?

- What is meant by radiation pattern?

- Define Radiation intensity?

- Define Beam efficiency?

- What is meant by reciprocity Theorem?

- What is meant by isotropic radiator?

- Define gain?

- Define self impedance?

- Define mutual impedance?

- ...Return To Antenna Theory FAQ's Main Page.


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