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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. The axes 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. The axes 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 = 0.4689
Eff_patchSilver = efficiency(ant_patchSilver,1e09)
Eff_patchSilver = 0.4101
Eff_patchAluminium = efficiency(ant_patchAluminium,1e09)
Eff_patchAluminium = 0.4669

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