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efficiency

Radiation efficiency of antenna

Description

example

E = efficiency(antenna,frequency) returns the radiation efficiency of the antenna over the specified frequency.

example

efficiency(antenna,frequency) plots the radiation efficiency of the antenna over the specified frequency.

Examples

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Create a top-hat monopole antenna.

m = metal('Lead');
ant = monopoleTopHat('Conductor',m);
show(ant)

Figure contains an axes object. The axes object with title monopoleTopHat antenna element contains 5 objects of type patch, surface. These objects represent Lead, feed.

Plot the radiation efficiency of the antenna over a frequency range of 20-80 MHz.

efficiency(ant,linspace(40e6,100e6,41))

Figure contains an axes object. The axes object with title Efficiency contains an object of type line.

Create and visualize patch microstrip antennas with PEC, copper, silver, and aluminium metal patches.

ant_patchPEC = patchMicrostrip('Substrate',dielectric('Air'),'Conductor',metal('PEC'));
ant_patchCopper = patchMicrostrip('Substrate',dielectric('FR4'),'Conductor',metal('Copper'));
ant_patchSilver = patchMicrostrip('Substrate',dielectric('FR4'),'Conductor',metal('Silver'));
ant_patchAluminium = patchMicrostrip('Substrate',dielectric('FR4'),'Conductor',metal('Aluminium'));

Compare the radiation efficiency of these antennas at the frequency of 1 GHz.

Eff_patchPEC = efficiency(ant_patchPEC,1e09)
Eff_patchPEC = 1
Eff_patchCopper = efficiency(ant_patchCopper,1e09)
Eff_patchCopper = 0.4697
Eff_patchSilver = efficiency(ant_patchSilver,1e09)
Eff_patchSilver = 0.4139
Eff_patchAluminium = efficiency(ant_patchAluminium,1e09)
Eff_patchAluminium = 0.4678

Input Arguments

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Input antenna, specified as an antenna object. The antenna object that you specify should be a single-feed structure.

Frequency range to calculate the radiation efficiency, specified as a scalar in hertz or a vector with each element unit in Hz.

Example: 50e6:1e6:100e6

Data Types: double

Output Arguments

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Radiation efficiency of the antenna, returned as a scalar or a vector with values in the range [0,1].

More About

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Radiation Efficiency

The time-average power density radiated by an antenna is:

where, r = radius of the sphere,

θ, φ = spherical coordinate angles,

E, H = electric and magnetic field intensity respectively.

The total power radiated by antenna is:

where, U = radiation intensity (W/ unit solid angle),

dΩ = element of solid angle.

The radiation efficiency is given as:

where, Pin = total input power.

Introduced in R2021a