phased.IsotropicAntennaElement

Create an isotropic antenna operating over a frequency range from 800 MHz to 1.2 GHz. The operating frequency is 1 GHz. Find the response of the antenna at boresight. Then, plot the polar-pattern elevation response of the antenna.

antenna = phased.IsotropicAntennaElement( ...
    'FrequencyRange',[800e6 1.2e9]);
fc = 1e9;

Obtain the response at boresight.

resp = antenna(fc,[0;0])

resp = 
1

Plot the response pattern.

pattern(antenna,fc,0,[-90:90],'CoordinateSystem','polar', ...
    'Type','powerdb','Normalize',true)

Create an isotropic antenna element using the phased.IsotropicAntennaElement System object™ and show that it does not support polarization.

antenna = phased.IsotropicAntennaElement('FrequencyRange',[1.0,10]*1e9);
isPolarizationCapable(antenna)

ans = logical
   0

The returned value 0 shows that the antenna element does not support polarization.

Compute the directivity of an isotropic antenna element in different directions.

Create an isotropic antenna element System object™.

antenna = phased.IsotropicAntennaElement();

First, specify that the directions of interest all at an elevation angle of zero degrees. The seven azimuth angles are centered around boresight (zero degrees azimuth and zero degrees elevation). Set the frequency to 1 GHz.

ang = [-30,-20,-10,0,10,20,30; 0,0,0,0,0,0,0];
freq = 1e9;

Compute the directivity along the constant elevation cut.

d = directivity(antenna,freq,ang)

d = 7×1

     0
     0
     0
     0
     0
     0
     0

Next, specify that the directions of interest all at an azimuth angle of zero degrees. All elevation angles are centered around boresight. The five elevation angles range from $-20$ to $+20$ degrees, inclusive. Set the frequency to 1 GHz.

ang = [0,0,0,0,0; -20,-10,0,10,20];
freq = 1e9;

Compute the directivity along the constant azimuth cut.

d = directivity(antenna,freq,ang)

d = 5×1

     0
     0
     0
     0
     0

For an isotropic antenna, the directivity is independent of direction.

Create an isotropic antenna element. Then, plot the antenna power pattern and directivity.

First, create the antenna.

antenna = phased.IsotropicAntennaElement;

Draw an azimuth cut of the power pattern at 0 degrees elevation. Assume the operating frequency is 1 GHz.

fc = 1e9;
pattern(antenna,fc,[-180:180],0,...
    'Type','power',...
    'CoordinateSystem','rectangular')

Draw the same azimuth cut of the antenna directivity.

pattern(antenna,fc,[-180:180],0,...
    'Type','directivity',...
    'CoordinateSystem','rectangular')

Construct an isotropic antenna operating in the frequency range from 800 MHz to 1.2 GHz. Compute the response at boresight at 1 GHz. Display the power pattern of the antenna at 1 GHz.

antenna = phased.IsotropicAntennaElement(...
    'FrequencyRange',[800e6 1.2e9]);
fc = 1e9;
resp = antenna(fc,[0;0])

resp = 
1

Plot the elevation power pattern of the antenna in polar coordinates.

pattern(antenna,fc,0,[-90:90],'Type','powerdb','CoordinateSystem','polar')

Construct an isotropic antenna operating over a frequency range from 800 MHz to 1.2 GHz. Then, plot the 3-D antenna field pattern.

Construct an isotropic antenna element.

antenna = phased.IsotropicAntennaElement(...
    'FrequencyRange',[800e6 1.2e9]);

Plot the 3-D magnitude pattern of the antenna at 1 GHz from $-30$ to $30$ degrees in both azimuth and elevation in 0.1 degree increments.

fc = 1e9;
pattern(antenna,fc,[-30:0.1:30],[-30:0.1:30],...
    'Type','efield',...
    'CoordinateSystem','polar')

Plot an azimuth cut of the directivity of an isotropic antenna element at 0 degrees elevation for all azimuth angles and at 30 degrees elevation for a small span of azimuth angles. Assume the operating frequency is 500 MHz.

Create the antenna element.

fc = 500e6;
antenna = phased.IsotropicAntennaElement('FrequencyRange',[100,900]*1e6);

Plot the pattern for all azimuth angles at 0 degrees elevation.

patternAzimuth(antenna,fc,0)

Plot the pattern for a reduced span of azimuth angles using the Azimuth parameter.

patternAzimuth(antenna,fc,30,'Azimuth',[-20:20])

Plot an elevation cut of directivity of an isotropic antenna element at 45 degrees azimuth for all elevation angles and at 45 degrees for a span of elevation angles. Assume the operating frequency is 500 MHz.

Create the antenna element.

fc = 500e6;
antenna = phased.IsotropicAntennaElement('FrequencyRange',[100,900]*1e6);

Plot the directivity for all elevation angles.

patternElevation(antenna,fc,45)

Plot the directivity for a span of elevation angles using the Elevation parameter.

patternElevation(antenna,fc,45,'Elevation',[-20:20])