plotResponse

System object: phased.HeterogeneousConformalArray
Namespace: phased

Plot response pattern of array

expand all in page

Syntax

plotResponse(H,FREQ,V)
plotResponse(H,FREQ,V,Name,Value)
hPlot = plotResponse(___)

Description

plotResponse(H,FREQ,V) plots the array response pattern along the azimuth cut, where the elevation angle is 0. The operating frequency is specified in FREQ. The propagation speed is specified in V.

plotResponse(H,FREQ,V,Name,Value) plots the array response with additional options specified by one or more Name,Value pair arguments.

hPlot = plotResponse(___) returns handles of the lines or surface in the figure window, using any of the input arguments in the previous syntaxes.

Input Arguments

H

Array object

FREQ

Operating frequency in Hertz specified as a scalar or 1-by-K row vector. Values must lie within the range specified by a property of H. That property is named FrequencyRange or FrequencyVector, depending on the type of element in the array. The element has no response at frequencies outside that range. If you set the 'RespCut' property of H to '3D', FREQ must be a scalar. When FREQ is a row vector, plotResponse draws multiple frequency responses on the same axes.

V

Propagation speed in meters per second.

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

CutAngle

Cut angle as a scalar. This argument is applicable only when RespCut is 'Az' or 'El'. If RespCut is 'Az', CutAngle must be between –90 and 90. If RespCut is 'El', CutAngle must be between –180 and 180.

Default: 0

Format

Format of the plot, using one of 'Line', 'Polar', or 'UV'. If you set Format to 'UV', FREQ must be a scalar.

Default: 'Line'

NormalizeResponse

Set this value to true to normalize the response pattern. Set this value to false to plot the response pattern without normalizing it. This parameter is not applicable when you set the Unit parameter value to 'dbi'.

Default: true

OverlayFreq

Set this value to true to overlay pattern cuts in a 2-D line plot. Set this value to false to plot pattern cuts against frequency in a 3-D waterfall plot. If this value is false, FREQ must be a vector with at least two entries.

This parameter applies only when Format is not 'Polar' and RespCut is not '3D'.

Default: true

Polarization

Specify the polarization options for plotting the array response pattern. The allowable values are |'None' | 'Combined' | 'H' | 'V' | where

  • 'None' specifies plotting a nonpolarized response pattern

  • 'Combined' specifies plotting a combined polarization response pattern

  • 'H' specifies plotting the horizontal polarization response pattern

  • 'V' specifies plotting the vertical polarization response pattern

For arrays that do not support polarization, the only allowed value is 'None'. This parameter is not applicable when you set the Unit parameter value to 'dbi'.

Default: 'None'

RespCut

Cut of the response. Valid values depend on Format, as follows:

  • If Format is 'Line' or 'Polar', the valid values of RespCut are 'Az', 'El', and '3D'. The default is 'Az'.

  • If Format is 'UV', the valid values of RespCut are 'U' and '3D'. The default is 'U'.

If you set RespCut to '3D', FREQ must be a scalar.

Unit

The unit of the plot. Valid values are 'db', 'mag', 'pow', or 'dbi'. This parameter determines the type of plot that is produced.

Unit valuePlot type
dbpower pattern in dB scale
magfield pattern
powpower pattern
dbidirectivity

Default: 'db'

Weights

Weight values applied to the array, specified as a length-N column vector or N-by-M matrix. The dimension N is the number of elements in the array. The interpretation of M depends upon whether the input argument FREQ is a scalar or row vector.

Weights DimensionsFREQ DimensionPurpose
N-by-1 column vectorScalar or 1-by-M row vectorApply one set of weights for the same single frequency or all M frequencies.
N-by-M matrixScalarApply all of the M different columns in Weights for the same single frequency.
1-by-M row vectorApply each of the M different columns in Weights for the corresponding frequency in FREQ.

AzimuthAngles

Azimuth angles for plotting array response, specified as a row vector. The AzimuthAngles parameter sets the display range and resolution of azimuth angles for visualizing the radiation pattern. This parameter is allowed only when the RespCut parameter is set to 'Az' or '3D' and the Format parameter is set to 'Line' or 'Polar'. The values of azimuth angles should lie between –180° and 180° and must be in nondecreasing order. When you set the RespCut parameter to '3D', you can set the AzimuthAngles and ElevationAngles parameters simultaneously.

Default: [-180:180]

ElevationAngles

Elevation angles for plotting array response, specified as a row vector. The ElevationAngles parameter sets the display range and resolution of elevation angles for visualizing the radiation pattern. This parameter is allowed only when the RespCut parameter is set to 'El' or '3D' and the Format parameter is set to 'Line' or 'Polar'. The values of elevation angles should lie between –90° and 90° and must be in nondecreasing order. When yous set the RespCut parameter to '3D', you can set the ElevationAngles and AzimuthAngles parameters simultaneously.

Default: [-90:90]

UGrid

U coordinate values for plotting array response, specified as a row vector. The UGrid parameter sets the display range and resolution of the U coordinates for visualizing the radiation pattern in U/V space. This parameter is allowed only when the Format parameter is set to 'UV' and the RespCut parameter is set to 'U' or '3D'. The values of UGrid should be between –1 and 1 and should be specified in nondecreasing order. You can set the UGrid and VGrid parameters simultaneously.

Default: [-1:0.01:1]

VGrid

V coordinate values for plotting array response, specified as a row vector. The VGrid parameter sets the display range and resolution of the V coordinates for visualizing the radiation pattern in U/V space. This parameter is allowed only when the Format parameter is set to 'UV' and the RespCut parameter is set to '3D'. The values of VGrid should be between –1 and 1 and should be specified in nondecreasing order. You can set VGrid and UGrid parameters simultaneously.

Default: [-1:0.01:1]

Examples

expand all

Open Live Script

This example shows how to construct an 8-element uniform circular array (UCA) with two different antenna patterns.

element1 = phased.CosineAntennaElement('CosinePower',1.5);
element2 = phased.CosineAntennaElement('CosinePower',1.8);
N = 8;
azang = (0:N-1)*360/N-180;
array = phased.HeterogeneousConformalArray( ...
    'ElementPosition',0.4*[zeros(1,N); cosd(azang); sind(azang)], ...
    'ElementNormal',zeros(2,N),'ElementSet',{element1,element2}, ...
    'ElementIndices',[1 1 1 1 2 2 2 2]);

Plot the array elevation response when the operating frequency is 1 GHz and the wave propagation speed is the speed of light.

c = physconst('LightSpeed');
fc = 1e9;
pattern(array,fc,0.0,-90:90,'PropagationSpeed',c,'CoordinateSystem','polar', ...
    'Type','powerdb')

Figure contains an axes object. The hidden axes object contains 3 objects of type line, text. This object represents 1 GHz .

Plot the directivity.

pattern(array,fc,0.0,-90:90,'PropagationSpeed',c,'CoordinateSystem','polar', ...
    'Type','directivity')

Figure contains an axes object. The hidden axes object contains 3 objects of type line, text. This object represents 1 GHz .

Open Live Script

This example shows how to construct a 24-element disk array using elements with two different antenna patterns and plot its response.

sElement1 = phased.CosineAntennaElement('CosinePower',1.5);
sElement2 = phased.CosineAntennaElement('CosinePower',1.8);
N = 8; azang = (0:N-1)*360/N-180;
p0 = [zeros(1,N);cosd(azang);sind(azang)];
posn = [0.6*p0, 0.4*p0, 0.2*p0];
sArray1 = phased.HeterogeneousConformalArray(...
    'ElementPosition',posn,...
    'ElementNormal', zeros(2,3*N),...
    'ElementSet',{sElement1,sElement2},...
    'ElementIndices',[1 1 1 1 1 1 1 1,...
    1 1 1 1 1 1 1 1,...
    2 2 2 2 2 2 2 2]);

Show the array.

viewArray(sArray1);

Figure contains an axes object. The hidden axes object with xlabel x axis (Az 0 El 0) -->, ylabel y axis --> contains 7 objects of type scatter, line, text.

Plot the elevation response of this array using uniform weights on the elements and also a tapered set of weights set by the Weights parameter. Using the ElevationAngles parameter, restrict the plot of the response from -60 to 60 degrees in 0.1 degree increments. Assume the operating frequency is 1 GHz and the wave propagation speed is the speed of light.

c = physconst('LightSpeed');
fc = 1e9;
wts1 = ones(3*N,1);
wts1 = wts1/sum(abs(wts1));
wts2 = [0.5*ones(N,1); 0.7*ones(N,1); 1*ones(N,1)];
wts2 = wts2/sum(abs(wts2));
plotResponse(sArray1,fc,c,'RespCut','El',...
    'Format','Polar',...
    'ElevationAngles',[-60:0.1:60],...
    'Weights',...
    [wts1,wts2],...
    'Unit','db');

Figure contains an axes object. The hidden axes object contains 4 objects of type line, text. These objects represent Weights 1 Ⓐ , Weights 2 .

As expected, the tapered weights broaden the mainlobe and reduce the sidelobes.

See Also

|