measuredAntenna

Store field data for analysis, excitation, pattern multiplication, or integration with RF systems

Since R2023a

Description

The measuredAntenna object enables you to perform port and field analysis using the field data of an antenna or array and to integrate it into an RF system.

You can import field data from .txt, .csv, .xlsx, or .ffd files into the MATLAB^® workspace and assign it to the corresponding properties of this object. To import data from .ffs files, use the ffsReader function.

The data can include:

• Cartesian electric and embedded electric field components (in V/m) at observation points

• Directivity at observation points

• Spherical coordinates of observation points

• Phase center

• Number of excitation ports

• Measurement frequencies

• S-parameters

You can use the measuredAntenna object as an exciter for curved reflector antennas from the antenna catalog and analyze them using the physical optics (PO) solver.

You can create RF sites from measured pattern data by specifying the Antenna property of the txsite or rxsite object as a measuredAntenna object.

You can use the measuredAntenna object as an element in linear, rectangular, and circular arrays to perform pattern multiplication on individual element patterns and to compute the overall radiation pattern of antenna arrays. To compute and visualize the array's overall radiation pattern, first set the properties of the measuredAntenna object using the pattern data and assign it to the Element property of the linearArray, rectangularArray, or circularArray objects. Then, use the patternMultiply function on these array objects.

To integrate the measuredAntenna object into RF systems, assign it to the:

• Antenna object parameter of the Antenna (RF Blockset) block

• Antenna Object parameter of the Transmitter, Receiver, and TxRxAntenna elements in the RF Budget Analyzer (RF Toolbox) app

• Antenna property of the Transmitter (Satellite Communications Toolbox) and Receiver (Satellite Communications Toolbox) objects

Creation

Syntax

m = measuredAntenna

m = measuredAntenna(PropertyName=Value)

Description

m = measuredAntenna creates a field data object with the x, y, and z-components of the electric field set to 0.1 V/m at a single observation point.

m = measuredAntenna(PropertyName=Value) sets properties using one or more name–value arguments. PropertyName is the property name and Value is the corresponding value. You can specify several name-value arguments in any order as PropertyName1=Value1,...,PropertyNameN=ValueN. Properties that you do not specify, retain their default values.

For example, m = measuredAntenna(NumPorts=4) creates an antenna field data object and sets the number ports to four.

You can also create a measuredAntenna object using the ffsReader function.

Properties

E — Radiated electric field

[0.1 0.1 0.1] (default) | P-by-3-by-F matrix

Radiated electric field, specified as a P-by-3-by-F matrix. P represents the number of observation points and F represents the number of frequencies over which the electric field is measured. The default value is [0.1 0.1 0.1] V/m at a single observation point. Use the FieldCoordinate property to select a coordinate system for the electric field. For the rectangular coordinate system, specify the electric field in terms of its Cartesian components [X Y Z] in V/m. For the polar coordinate system, specify the electric field in terms of its polar components [Phi Theta R] in V/m.

Example: E(:,:,1) = [0.5 0.3 0.7]

Example: E(1,:,:) = [0.1 0.1 0.1; 0.2 0.3 0.15;...0.5 0.45 0.35]

Data Types: double
Complex Number Support: Yes

Directivity — Directivity of antenna or array

[] (default) | P-by-F matrix

Since R2026a

Directivity of the antenna or array, specified as a P-by-F matrix in dBi. P represents the number of observation points and F is the number of frequencies used for measurements or simulation. The default directivity value is an empty vector.

Example: [1.8 1.95 2 2.01]

Example: [1.8 1.95 2 2.01; ...; 2.1 2.5 2.66 2.7]

Data Types: double

Direction — Direction of radiated electric field

[0 90 100] (default) | P-by-3 matrix

Spherical coordinates of the observation points, specified as a P-by-3 matrix. P represents the number of observation points and the coordinates are specified as [Azimuth(degree) Elevation(degree) Radius(meter)]. The default value is a single observation point at [0 90 100].

Example: [30 60 200]

Example: [0 90 100; ...; 359 359 100]

Data Types: double

PhaseCenter — Phase center of measured antenna

[0 0 0.075] (default) | 1-by-3 vector

Cartesian coordinates of the phase center of the measured antenna in meter, specified as a 1-by-3 vector in [X Y Z] order. The default phase center is at [0 0 0.075]. Phase center is defined as a point in space from which, when emitted, the far-field phase fronts remain spherical in a certain angular area of interest. PhaseCenter denotes the average phase center of the incident electric field, E.

Example: [0 1 1]

Data Types: double

NumPorts — Number of excitation ports

1 (default) | positive scalar integer

Number of excitation ports in the measured antenna or array, specified as a positive scalar integer. Number of antenna ports specified in this property must be equal to the number of antenna ports in EmbeddedE property.

Example: 2

Data Types: double

FieldFrequency — Frequencies used to measure electric field

1e9 (default) | scalar | F-by-1 vector

Frequencies at which the electric field of the antenna or array was measured, specified as a scalar for a single frequency or a F-by-1 vector for multiple frequencies in Hertz, where F is the number of frequencies.

Example: 1e9

Example: [1e9 1.25e9 1.5e9]

Data Types: double

FieldCoordinate — Coordinate system for field data

"rectangular" (default) | "polar"

Coordinate system for the measured field data, specified as a string amongst:

• rectangular - Cartesian coordinates, where the points are specified as [x y z].

• polar - Spherical coordinates, where the points are specified as [azimuth elevation radial].

Example: "polar"

Data Types: string

Azimuth — Azimuth angles used to measure electric field

0 (default) | scalar | A-by-1 vector

Azimuth angles used to measure electric field, specified as a scalar or A-by-1 vector in degrees, where A is the number of azimuth angles.

Example: [0:5:90]

Data Types: double

Elevation — Elevation angles used to measure electric field

90 (default) | scalar | E-by-1 vector

Elevation angles used to measure electric field, specified as a scalar or E-by-1 vector in degrees, where E is the number of elevation angles.

Example: [0:5:90]

Data Types: double

Sparameters — Scattering parameters of antenna or array

"[]" (default) | sparameters object

S-parameters for all excitation ports at each frequency, specified as a sparameters object.

Example: sparameters("sample.s2p")

Example: sparameters(dipole,70e6,50)

Example: sparameters(linearArray,140e6)

Data Types: double

AmplitudeTaper — Excitation amplitude of array elements in Volts

1 (default) | positive scalar | positive vector of size 1-by-NumPorts positive vector

Excitation amplitude of array elements in Volts, specified as one of these options:

• Positive scalar — Use this value to specify uniform amplitude across the individual elements.

• Positive vector of size 1-by-NumPorts — Use this value to specify non-uniform amplitude across the individual elements.

The default AmplitudeTaper is 1 Volt. You can specify this property when the NumPorts property is set to a value greater than 1.

Example: 2

Example: [2 4]

Data Types: double

PhaseShift — Phase shift of array elements in degrees

0 (default) | numeric scalar | numeric vector of size 1-by-NumPorts

Phase shift of array elements in degrees, specified as one of these options:

• Numeric scalar — Use this value to specify uniform phase shift across the individual elements.

• Numeric vector of size 1-by-NumPorts — Use this value to specify non-uniform phase shift across the individual elements.

The default PhaseShift is zero degrees. PhaseShift values correspond to the respective excitation voltages of the individual elements in the array. You can specify this property when the NumPorts property is set to a value greater than 1.

Example: 45

Example: [45 -45]

Data Types: double

EmbeddedE — Electric field of individual element in array

"[]" (default) | P-by-3-by-N-by-F 4-D array

Cartesian components (P-by-3) of embedded electric field magnitude in V/m when the FieldCoordinate is "rectangular", for each port (N) at each frequency (F) at each observation point in the Direction property, specified as a 4-D array. Number of points is defined by P.

When the FieldCoordinate is "polar", the three columns in P-by-3 matrix represent azimuth angle, elevation angle, and radial magnitude. You can specify this property when the NumPorts property is set to a value greater than 1.

Example: Let EmbeddedE = emb in a rectangular coordinate system. To access the electric field data for a single port at a single frequency, use emb(:,:,1,1).

Data Types: double
Complex Number Support: Yes

TerminationImpedance — Termination impedance for array elements

50 (default) | real scalar

Impedance to terminate other ports except the excitation port while computing the embedded pattern, specified as a real scalar. You can specify this property when the NumPorts property is set to a value greater than 1.

Example: 75

Data Types: double

CalculateTotalField — Option to calculate total electric field from embedded field data

false or 0 (default) | true or 1

Option to calculate the total electric field from embedded field data, specified as one of these options:

• Numeric or logical 0(false) — Use this value to disable this option.

• Numeric or logical 1(true) — Use this value to enable this option.

By default, this option is disabled. When this option is enabled, the EHfields and pattern functions use the calculated total electric field in their results. You can specify this property when the NumPorts property is set to a value greater than 1.

Example: true

Data Types: logical

Object Functions

EHfields	Electric and magnetic fields of antennas or embedded electric and magnetic fields of antenna element in arrays
pattern	Plot radiation pattern of antenna, array, or embedded element of array
sparameters	Calculate S-parameters for antenna or array

Note

When measuredAntenna is an input argument to the above functions:

• The EHfields function can be used only to visualize the E-field data contained in the E property of the measuredAntenna.

• The pattern function can have its Type argument set to efield, directivity, power, powerdb, or phase.

• The sparameters function plots the S-parameters when no output argument is specified or creates a sparameters object when an output argument is specified.

Examples

Excite Parabolic Reflector Using E-field Data

This example shows how to use the measured electric field data of a dipole antenna to excite a parabolic reflector structure. The example uses EHfields function to generate the electric field data. You can import the electric field data of any external antenna into the measuredAntenna object. The electric field magnitude is expressed in V/m and coordinates are expressed in meters and degrees.

Create Dipole antenna, save field data and plot electric field

Design a dipole antenna operating at 10 GHz. Save the complex E-field data of this dipole antenna in a variable.

freq = 10e9;
ant = design(dipole(Tilt=90,TiltAxis=[0 1 0]),freq);
E = EHfields(ant,freq)

E = 3×441 complex

  12.2492 +50.7204i  10.9830 +50.0817i   7.2868 +48.1070i   1.4638 +44.6408i  -5.9963 +39.4936i -14.4447 +32.5478i -23.1139 +23.9147i -31.1701 +14.1574i -37.7710 + 4.5564i -42.1360 - 2.7961i -43.6684 - 5.6012i -42.1360 - 2.7961i -37.7710 + 4.5564i -31.1701 +14.1574i -23.1139 +23.9147i -14.4447 +32.5478i  -5.9963 +39.4936i   1.4638 +44.6408i   7.2868 +48.1070i  10.9830 +50.0817i  12.2492 +50.7204i  12.2492 +50.7204i  11.1051 +50.1436i   7.7649 +48.3712i   2.5080 +45.2950i  -4.2156 +40.7988i -11.8109 +34.8519i -19.5772 +27.6408i -26.7579 +19.7300i -32.6013 +12.2039i -36.4360 + 6.6227i -37.7749 + 4.5369i -36.4360 + 6.6227i -32.6013 +12.2039i -26.7579 +19.7300i -19.5772 +27.6408i -11.8109 +34.8519i  -4.2156 +40.7988i   2.5080 +45.2950i   7.7649 +48.3712i  11.1051 +50.1436i  12.2492 +50.7204i  12.2492 +50.7204i  11.4228 +50.3047i   9.0112 +49.0475i   5.2258 +46.9296i   0.4051 +43.9584i  -5.0085 +40.2214i -10.5012 +35.9467i -15.5309 +31.5501i
   0.0191 + 0.0071i   0.0155 + 0.0116i   0.0115 + 0.0155i   0.0072 + 0.0187i   0.0027 + 0.0210i  -0.0020 + 0.0221i  -0.0065 + 0.0223i  -0.0106 + 0.0218i  -0.0137 + 0.0210i  -0.0158 + 0.0203i  -0.0165 + 0.0201i  -0.0158 + 0.0203i  -0.0137 + 0.0210i  -0.0106 + 0.0218i  -0.0065 + 0.0223i  -0.0020 + 0.0221i   0.0027 + 0.0210i   0.0072 + 0.0187i   0.0115 + 0.0155i   0.0155 + 0.0116i   0.0191 + 0.0071i   0.0191 + 0.0071i  -0.3208 - 0.2160i  -1.3069 - 0.9109i  -2.8600 - 2.1211i  -4.8516 - 3.8972i  -7.1112 - 6.2625i  -9.4357 - 9.1600i -11.6018 -12.3805i -13.3806 -15.4882i -14.5582 -17.8213i -14.9717 -18.6996i -14.5582 -17.8213i -13.3806 -15.4882i -11.6018 -12.3805i  -9.4357 - 9.1600i  -7.1112 - 6.2625i  -4.8516 - 3.8972i  -2.8600 - 2.1211i  -1.3069 - 0.9109i  -0.3208 - 0.2160i   0.0191 + 0.0071i   0.0191 + 0.0071i  -0.5280 - 0.3556i  -2.1176 - 1.4606i  -4.6137 - 3.3253i  -7.7981 - 5.9465i -11.3836 - 9.2543i -15.0340 -13.0573i -18.3899 -16.9940i
   0.0000 + 0.0001i  -7.2267 - 4.8924i -13.8167 - 9.7575i -19.1754 -14.4814i -22.7937 -18.7870i -24.2914 -22.1762i -23.4561 -23.9067i -20.2734 -23.0454i -14.9513 -18.7079i  -7.9486 -10.6411i   0.0000 + 0.0000i   7.9486 +10.6411i  14.9513 +18.7079i  20.2734 +23.0454i  23.4561 +23.9067i  24.2914 +22.1762i  22.7937 +18.7870i  19.1754 +14.4814i  13.8167 + 9.7575i   7.2267 + 4.8924i  -0.0000 - 0.0001i   0.0000 + 0.0001i  -6.8731 - 4.6457i -13.1344 - 9.2239i -18.2136 -13.5889i -21.6250 -17.4521i -23.0095 -20.3392i -22.1726 -21.5919i -19.1151 -20.4533i -14.0568 -16.3107i  -7.4547 - 9.1466i   0.0000 + 0.0000i   7.4547 + 9.1466i  14.0568 +16.3107i  19.1151 +20.4533i  22.1726 +21.5919i  23.0095 +20.3392i  21.6250 +17.4521i  18.2136 +13.5889i  13.1344 + 9.2239i   6.8731 + 4.6457i  -0.0000 - 0.0001i   0.0000 + 0.0001i  -5.8454 - 3.9358i -11.1561 - 7.7223i -15.4375 -11.1610i -18.2748 -13.9710i -19.3715 -15.7815i -18.5823 -16.1686i -15.9384 -14.7525i

Plot the electric field vectors of this dipole antenna.

fig = figure; 
EHfields(ant,freq,ViewField="E");

Extract coordinates of electric field points and pass field data to measuredAntenna

Extract the Cartesian coordinates of direction vectors from the electric field plot using quiver. Convert these Cartesian coordinates into spherical coordinates using cart2sph function.

quH = fig.Children(3).Children;
pts = [quH.XData;quH.YData;quH.ZData];
[phi,theta,radius] = cart2sph(pts(1,:),pts(2,:),pts(3,:));
dir = [rad2deg(phi)' 90-rad2deg(theta)' radius'];

Create a measuredAntenna object and pass the electric field data (in V/m.), spherical coordinates of the electric field points, and the phase center of the this field to the respective properties of the measuredAntenna object.

ms = measuredAntenna;
ms.E = E';
ms.Direction = dir;
lambda = 3e8/freq;
f = 5 * lambda;
ms.PhaseCenter = [0 0 f];
ms.FieldFrequency = freq;

Create parabolic reflector antenna with measuredAntenna as exciter

Create a parabolic reflector antenna with the measuredAntenna data as Exciter. Plot the radiation pattern of this antenna at 10 GHz.

back = reflectorParabolic;
back.Exciter = ms;
figure
pattern(back,10e9)

Import and Visualize Measured Radiation Pattern Data

This example shows how to import and analyze the measured pattern data of a linear array.

Import Measured Pattern Data

Define the frequency range of the data and number of antenna elements in the array. Import the data from a text file using readmatrix function.

The text file contains measured field data for a linear array of dipoles at 3 frequencies 1.6GHz, 2GHz, and 2.4GHz.

fRange = [1.6e9 2e9 2.4e9];
numAnt = 2;
patternData = readmatrix("MeasuredData.txt");
patternData

patternData = 2701×30 complex
102 ×

   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.8000 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
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   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.6500 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.6000 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.5500 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
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   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.4500 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.4000 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.3500 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.3000 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.2500 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.2000 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.1500 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i  -1.1000 + 0.0000i  -0.9000 + 0.0000i   0.1500 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i  -0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i   0.0000 + 0.0000i   0.0000 - 0.0000i   0.0000 - 0.0000i
      ⋮

Extract the field data, direction data, and embedded field data from the imported data. Further, extract azimuth and elevation data from the direction data.

% E-field data
eField(:,:,1) = patternData(:,1:3);
eField(:,:,2) = patternData(:,4:6);
eField(:,:,3) = patternData(:,7:9);

% Direction, azimuth, and elevation data
dir = patternData(:,10:12);
az = dir(1:73,1);
el = dir(1:73:end,2);

% Embedded E-field data
embE(:,:,1,1) = patternData(:,13:15);
embE(:,:,2,1) = patternData(:,16:18);
embE(:,:,1,2) = patternData(:,19:21);
embE(:,:,2,2) = patternData(:,22:24);
embE(:,:,1,3) = patternData(:,25:27);
embE(:,:,2,3) = patternData(:,28:30);

Import and extract S-parameters data from Touchstone files.

% Import S-parameters data
sParamData1 = sparameters("Parameters_1.6ghz.s2p");
sParamData2 = sparameters("Parameters_2ghz.s2p");
sParamData3 = sparameters("Parameters_2.4ghz.s2p");

% Extract S-parameters data
sParam(:,:,1) = sParamData1.Parameters;
sParam(:,:,2) = sParamData2.Parameters;
sParam(:,:,3) = sParamData3.Parameters;
sParamFreq(:,1) = sParamData1.Frequencies;
sParamFreq(:,2) = sParamData2.Frequencies;
sParamFreq(:,3) = sParamData3.Frequencies;
sParam

sParam = 
sParam(:,:,1) =

   0.6991 - 0.5140i   0.0523 + 0.0366i
   0.0523 + 0.0366i   0.6991 - 0.5140i


sParam(:,:,2) =

   0.2076 - 0.0674i  -0.0918 - 0.1830i
  -0.0918 - 0.1830i   0.2076 - 0.0674i


sParam(:,:,3) =

   0.6581 + 0.2567i  -0.0490 + 0.0871i
  -0.0490 + 0.0871i   0.6581 + 0.2567i

sParamFreq

sParamFreq = 1×3
109 ×

    1.6000    2.0000    2.4000

s = sparameters(sParam,sParamFreq);

Assign Data to measuredAntenna

Assign the extracted data to a measuredAntenna object.

mesAnt = measuredAntenna(E=eField, Direction=dir, NumPorts=numAnt,...
                Azimuth=az, Elevation=el, FieldCoordinate="polar",...
                EmbeddedE=embE, FieldFrequency=fRange, Sparameters=s)

mesAnt = 
  measuredAntenna with properties:

                       E: [2701×3×3 double]
             Directivity: []
               Direction: [2701×3 double]
             PhaseCenter: [0 0 0.0750]
                NumPorts: 2
          FieldFrequency: [3×1 double]
         FieldCoordinate: "polar"
                 Azimuth: [-180 -175 -170 -165 -160 -155 -150 -145 -140 -135 -130 -125 -120 -115 -110 -105 -100 -95 -90 -85 -80 -75 -70 -65 -60 -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 … ] (1×73 double)
               Elevation: [-90 -85 -80 -75 -70 -65 -60 -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90]
             Sparameters: [1×1 sparameters]
          AmplitudeTaper: 1
              PhaseShift: 0
               EmbeddedE: [2701×3×2×3 double]
    TerminationImpedance: 50
     CalculateTotalField: 0

Visualize Measured Pattern Data

Plot the radiation pattern and electric field for this measuredAntenna at 2GHz, while plot S-parameters over the entire frequency range.

pattern(mesAnt,fRange(2),Type="efield")

EHfields(mesAnt,fRange(2))

sp = sparameters(mesAnt,fRange);
rfplot(sp)

Import and Visualize Radiation Pattern Data from FFD File

This example shows how to import radiation pattern data from a .ffd file to workspace and visualize it. The .ffd file contains far-field data generated by the HFSS™ software. The data is visualized using object functions of the measuredAntenna object.

Load the radiation pattern data from the .ffd file into the workspace by using the loadData helper function (defined in the supporting function section of this example). Specify the coordinate system angle convention used for this data in the .ffd file.

fileName = sprintf("RefFFDdata.ffd");
CoordinateSystem = "Phi-Theta";
[theta1,phi1,numFreqs,Etheta,Ephi,freqs] = loadData(fileName,CoordinateSystem);
if CoordinateSystem == "Phi-Theta"
    elev = 90 - theta1;
else
    elev = theta1;
end

Calculate the number of data points.

numPt = numel(theta1)*numel(phi1);

Extract the electric field data from the data in the workspace.

ESph = [Ephi;Etheta;zeros(numPt,3)];
eField = reshape(ESph,numPt,3,numFreqs);

Calculate the spherical coordinates of the electric field points.

lambda = 3e8/max(freqs);
radius = 100*lambda*ones(numPt,1);
[theta,phi] = meshgrid(elev,phi1);
phi = phi(:);
theta = theta(:);
direction = [phi theta radius];

Create a measuredAntenna object with number of ports equal to those present in the .ffd file data. Set the E property value to eField. Set the Direction property using calculated spherical coordinates. Set the Azimuth property to phi1 and Elevation property to elev. Specify the phase center. This example assumes the phase center at (0,0,0). Set the FieldFrequency property using the frequencies of the electric field data.

mAnt = measuredAntenna(NumPorts=1);
mAnt.E = eField;
mAnt.Direction = direction;
mAnt.PhaseCenter = [0 0 0];
mAnt.FieldFrequency = freqs;
mAnt.Azimuth = phi1;
mAnt.Elevation = elev;
mAnt.FieldCoordinate = 'polar';

Visualize the radiation patterns at the individual frequencies.

for i=1:numFreqs
figure
pattern(mAnt,freqs(i))
title(strcat("Radiation Pattern at ",num2str(freqs(i)/1e9)," GHz"))
end

Visualize the corresponding electric fields.

for i=1:numFreqs
figure
EHfields(mAnt,freqs(i))
title(strcat("Electric Field at ",num2str(freqs(i)/1e9)," GHz"))
end

Supporting Function

The loadData helper function extracts the number of frequencies, angle values for the data points, and the electric field values from the .ffd file.

function [theta1,phi1,numFreqs,Etheta,Ephi,freqs] = loadData(fileName,CoordinateSystem)
fid = fopen(fileName);

if CoordinateSystem == "Phi-Theta"
    numHeaderLines = 3;
else
    textscan(fid,'%s',1);
    numHeaderLines = 4;
end

data = num2cell(fscanf(fid,'%d',3));
theta1 = linspace(data{:});
data = num2cell(fscanf(fid,'%d',3));
phi1 = linspace(data{:});
C1 = textscan(fid,'%s %d',1);
numFreqs = C1{2};
fclose(fid);

Mfull = readmatrix(fileName,FileType="text",NumHeaderLines=numHeaderLines);
freqs = Mfull(isnan(Mfull(:,1)),2);
MData = Mfull(~isnan(Mfull(:,1)),:);
Etheta = reshape(MData(:,1) + 1j*MData(:,2),length(phi1)*length(theta1),[]);
Ephi = reshape(MData(:,3) + 1j*MData(:,4),length(phi1)*length(theta1),[]);
end

Perform Pattern Multiplication for Rectangular Array Using Measured Element Pattern Data

Load the measured E-field data. Define the field frequency, azimuth, and elevation angles.

load("mesAnt_rect_array.mat")
freq = 3e9;
az = -180:5:180;
el = -90:5:90;

Create a measuredAntenna object and set its properties using the defined parameters.

mesAnt = measuredAntenna(E=Efield,Direction=Dir,NumPorts=1, ...
    Azimuth=az,Elevation=el,FieldCoordinate="rectangular", ...
    FieldFrequency=freq)

mesAnt = 
  measuredAntenna with properties:

                  E: [2701×3 double]
        Directivity: []
          Direction: [2701×3 double]
        PhaseCenter: [0 0 0.0750]
           NumPorts: 1
     FieldFrequency: 3.0000e+09
    FieldCoordinate: "rectangular"
            Azimuth: [-180 -175 -170 -165 -160 -155 -150 -145 -140 -135 -130 -125 -120 -115 -110 -105 -100 -95 -90 -85 -80 -75 -70 -65 -60 -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 … ] (1×73 double)
          Elevation: [-90 -85 -80 -75 -70 -65 -60 -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90]
        Sparameters: []

Create a 2-by-2 rectangular array with 0.0665 m row and column spacing and use the measuredAntenna object as its element.

rectArr = rectangularArray(Element=mesAnt,RowSpacing=0.0665,ColumnSpacing=0.0665)

rectArr = 
  rectangularArray with properties:

           Element: [1×1 measuredAntenna]
              Size: [2 2]
        RowSpacing: 0.0665
     ColumnSpacing: 0.0665
           Lattice: 'Rectangular'
    AmplitudeTaper: 1
        PhaseShift: 0
              Tilt: 0
          TiltAxis: [1 0 0]

Perform pattern multiplication and plot the resultant array directivity pattern.

figure 
patternMultiply(rectArr,freq)

Integrate Reconstructed 3-D Pattern from Vertical and Horizontal Slices

Import horizontal and vertical slice directivity data of a dipole antenna operating at 75 MHz. This data includes magnitude, phi, and theta values at an angular resolution of 5 degrees.

load("slices_data.mat");

Reconstruct 3-D pattern of the antenna from the horizontal and vertical slices.

[patS,thout,phiout] = patternFromSlices(vertSlice,theta,horizSlice,phi,Method="CrossWeighted");

Calculate azimuth and elevation values.

frequency = 75e6;
lambda = physconst("LightSpeed")/frequency;
R = 100*lambda;
[az,el] = meshgrid(phiout,90-thout);
Dir = [az(:) el(:) R*ones(numel(az),1)];

Create a measuredAntenna object and set its properties. You can integrate this object into your workflow.

mAnt = measuredAntenna(E=[],Directivity=patS(:),Direction=Dir, ...
    FieldFrequency=frequency,FieldCoordinate="polar", ...
    PhaseCenter=[0 0 0],Azimuth=phiout,Elevation=90-thout);

Compute pattern with default resolution.

figure
pattern(mAnt,frequency)

Compute pattern with lower resolution.

figure
pattern(mAnt,frequency,-180:15:180,-90:10:90)

Compute pattern with higher resolution.

figure
pattern(mAnt,frequency,-180:1:180,-90:1:90)

Import and Plot Pattern Data with Multiple Frequencies

Load the file containing pattern data into the workspace. Define frequencies, azimuth, and elevation ranges for the data.

load("pattern_data.mat")
freq = 70e6:10e6:100e6;

Calculate directions for the pattern data. Create a measuredAntenna object and set its properties using the pattern data.

lambda = physconst("LightSpeed")/70e6;
R = 100*lambda;
[az1, el1] = meshgrid(az,el);

Dir = [az1(:) el1(:) R*ones(numel(az1),1)];

mAnt = measuredAntenna(E=[],Directivity=patT,Direction=Dir,FieldFrequency=freq, ...
    Azimuth=az,Elevation=el,PhaseCenter=[0 0 0]);

Calculate and plot the directivity pattern at 75 MHz. The measuredAntenna object interpolates pattern data for the frequencies, azimuth, and elevation angles that are within the specified range.

[mPat,mAz,mEl] = pattern(mAnt,75e6,-180:25:180,-90:20:90)

mPat = 10×15

  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273
   -9.2430   -9.2447   -9.2458   -9.2464   -9.2465   -9.2460   -9.2450   -9.2434   -9.2415   -9.2396   -9.2383   -9.2380   -9.2387   -9.2403   -9.2423
   -3.0441   -3.0446   -3.0449   -3.0452   -3.0452   -3.0450   -3.0447   -3.0442   -3.0438   -3.0435   -3.0432   -3.0432   -3.0433   -3.0436   -3.0440
    0.3401    0.3399    0.3395    0.3391    0.3391    0.3394    0.3398    0.3401    0.3400    0.3396    0.3393    0.3392    0.3394    0.3398    0.3401
    1.9635    1.9632    1.9626    1.9621    1.9620    1.9625    1.9631    1.9635    1.9633    1.9626    1.9620    1.9619    1.9622    1.9629    1.9634
    1.9635    1.9632    1.9625    1.9620    1.9619    1.9624    1.9631    1.9635    1.9633    1.9627    1.9621    1.9620    1.9623    1.9630    1.9634
    0.3401    0.3399    0.3396    0.3392    0.3392    0.3395    0.3399    0.3401    0.3399    0.3395    0.3392    0.3391    0.3393    0.3397    0.3400
   -3.0441   -3.0437   -3.0434   -3.0432   -3.0432   -3.0433   -3.0437   -3.0441   -3.0445   -3.0449   -3.0451   -3.0452   -3.0451   -3.0447   -3.0443
   -9.2430   -9.2411   -9.2393   -9.2382   -9.2381   -9.2390   -9.2407   -9.2426   -9.2444   -9.2457   -9.2463   -9.2465   -9.2461   -9.2452   -9.2437
  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273  -49.9273

mAz = 1×15

  -180  -155  -130  -105   -80   -55   -30    -5    20    45    70    95   120   145   170

mEl = 1×10

   -90   -70   -50   -30   -10    10    30    50    70    90

figure
pattern(mAnt,75e6)

Calculate and plot the directivity pattern at 90 MHz.

[mPat1,mAz1,mEl1] = pattern(mAnt,90e6,-180:25:180,-90:20:90)

mPat1 = 10×15

  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580
  -10.2357  -10.2503  -10.2619  -10.2685  -10.2691  -10.2636  -10.2529  -10.2388  -10.2237  -10.2106  -10.2021  -10.2001  -10.2048  -10.2154  -10.2296
   -3.5977   -3.6030   -3.6073   -3.6098   -3.6101   -3.6080   -3.6040   -3.5988   -3.5935   -3.5889   -3.5861   -3.5854   -3.5870   -3.5906   -3.5955
    0.2452    0.2430    0.2408    0.2393    0.2392    0.2404    0.2425    0.2448    0.2467    0.2479    0.2485    0.2486    0.2483    0.2475    0.2460
    2.1480    2.1471    2.1457    2.1447    2.1446    2.1455    2.1468    2.1479    2.1481    2.1477    2.1472    2.1470    2.1474    2.1480    2.1481
    2.1480    2.1481    2.1476    2.1471    2.1470    2.1475    2.1480    2.1481    2.1473    2.1460    2.1448    2.1445    2.1452    2.1465    2.1477
    0.2452    0.2470    0.2481    0.2486    0.2486    0.2482    0.2473    0.2456    0.2434    0.2412    0.2395    0.2391    0.2401    0.2420    0.2444
   -3.5977   -3.5925   -3.5882   -3.5857   -3.5855   -3.5876   -3.5915   -3.5966   -3.6020   -3.6066   -3.6095   -3.6102   -3.6086   -3.6049   -3.5999
  -10.2357  -10.2208  -10.2085  -10.2012  -10.2005  -10.2065  -10.2181  -10.2327  -10.2475  -10.2599  -10.2676  -10.2695  -10.2652  -10.2554  -10.2418
  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580  -50.0580

mAz1 = 1×15

  -180  -155  -130  -105   -80   -55   -30    -5    20    45    70    95   120   145   170

mEl1 = 1×10

   -90   -70   -50   -30   -10    10    30    50    70    90

figure
pattern(mAnt,90e6)

Create RF Sites Using Pattern Data

Load the pattern data file into the workspace. Define the frequency for the pattern data and calculate directions. Create a measuredAntenna object and set its properties using the imported pattern data.

load("rf_site_data.mat");
frequency = 2.5e9;
lambda = physconst("LightSpeed")/frequency;
R = 100*lambda;
[az1, el1] = meshgrid(az,el);
Dir = [az1(:) el1(:) R*ones(numel(az1),1)];
mAnt = measuredAntenna(E=[],Directivity=pat(:),Direction=Dir,FieldFrequency=frequency, ...
    Azimuth=az,Elevation=el,PhaseCenter=[0 0 0]);

Create a site viewer, and Tx and Rx sites with their Antenna property specified using the measuredAntenna object.

viewer = siteviewer(Buildings="chicago.osm");

Warning: Unable to access basemap 'satellite', which uses an online source. Using 'darkwater' instead. More details: The connection to the URL 'https://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer' timed out.

tx = txsite(Latitude=41.8800, ...
    Longitude=-87.6295, ...
    TransmitterFrequency=2.5e9,Antenna=mAnt);

rx = rxsite(Latitude=41.881352, ...
    Longitude=-87.629771, ...
    AntennaHeight=30,Antenna=mAnt);

Use the raytracing propagation model to calculate the signal strength and perform raytracing.

pm = propagationModel("raytracing");
ss = sigstrength(rx,tx,pm)

ss = 
-50.0058

raytrace(tx,rx,pm)

Plot the radiation pattern of the transmitter.

pattern(tx)

Integrate Pattern Data into Satellite Transmitter

Create the satelliteScenario object.

startTime = datetime(2020,11,25,0,0,0);
stopTime = startTime + days(1);
sampleTime = 60;
sc = satelliteScenario(startTime,stopTime,sampleTime);

Create the Satellite object. Create the Gimbal object for the satellite scenario using the Satellite object.

semiMajorAxis = 10000000;                                 % meters
eccentricity = 0;
inclination = 60;                                         % degrees
rightAscensionOfAscendingNode = 0;                        % degrees
argumentOfPeriapsis = 0;                                  % degrees
trueAnomaly = 0;                                          % degrees
sat = satellite(sc,semiMajorAxis,eccentricity,inclination, ...
    rightAscensionOfAscendingNode,argumentOfPeriapsis, ...
    trueAnomaly,Name="Satellite");
gimbaltxSat = gimbal(sat);

Specify parameters for the Transmitter object.

frequency = 27e9;                                    % Hz
power = 20;                                          % dBW
bitRate = 20;                                        % Mbps
systemLoss = 3;                                      % dB

Load the pattern data file into the workspace. Calculate the directions. Create a measuredAntenna object and set its properties using the imported pattern data.

load("ant_sat_data.mat");
lambda = physconst("LightSpeed")/frequency;
R = 100*lambda;
[az1, el1] = meshgrid(az,el);

Dir = [az1(:) el1(:) R*ones(numel(az1),1)];

mAnt = measuredAntenna(E=[],Directivity=pat(:),Direction=Dir, ...
    FieldFrequency=frequency,Azimuth=az,Elevation=el);

Create a Transmitter object. View the antenna radiation pattern in the scenario.

txSat = transmitter(gimbaltxSat,Name="Satellite Transmitter",Frequency=frequency, ...
    Power=power,BitRate=bitRate,SystemLoss=systemLoss,Antenna=mAnt);
viewer = satelliteScenarioViewer(sc);
pattern(txSat);

Use Measured Antenna Object in Antenna Block

This example shows how to use measuredAntenna object in the Antenna block to model a measured antenna or array characterized by means of its S-parameters and frequency dependent far-field radiation pattern including both polarization components. The measuredAntenna object lets you replace the physical antennas from the antenna catalog with measured field data of the antenna. This example extracts data from a linear array to create a measuredAntenna object using hcreate_mAnt helper function.

System Configuration

Define the carrier frequency in Hz and set it in these parameters:

• Radiated carrier frequency parameter in the Transmit Antenna block

• Incident carrier frequency parameter in the Receiver Antenna block

• Carrier frequencies parameter in the Inport and Outport blocks

FreqCarrier = 5e9;

Define gain for the Gain block. This Gain block acts as a free-space path-loss channel.

lambdaCarrier = physconst('lightspeed')/FreqCarrier; %[m]

Define the input impedance of the low noise amplifier (LNA) in ohms.

Zin_r =71.3819 - 1j*2.1795;

Define the available input power in dBm for the two RF transmitter chains and assign the variables to Pin 1 and Pin 2 in the Constant block.

Pin1 = -30;
Pin2 = -30;

Create a linear antenna array and extract data from it to create a measuredAntenna object. The data extracted from the linear array is a substitute of real-world measured data that can be inputted by changing the hcreate_mAnt helper function so as to read the embedded electric fields from data file.

dist = lambdaCarrier*0.5;
d1 = design(dipole,FreqCarrier);
antElems = [d1 copy(d1)];
la = linearArray('Element',antElems,'ElementSpacing',dist);
la.TiltAxis = [0 1 0];
la.Tilt = 90;
freqRange = (4.5:0.05:5.5)*1e9;
[mAnt,R] = hcreate_mAnt(la,freqRange);

Compute impedances in ohms for PA and PA1 Amplifier blocks in the transmitter.

z = impedance(la,freqRange);
z = z(freqRange==FreqCarrier,:);
Zin_t1 = z(1);
Zin_t2 = z(2);

Simulate Model

Open and simulate the measuredAnt.slx model. Observe the output power at the receiver.

open_system("measuredAnt.slx")
sim("measuredAnt.slx");

Version History

Introduced in R2023a

R2026a: Specify directivity values

Use the new Directivity property to specify measured antenna or array directivity values.

R2024a: Calculate total electric field using embedded field data

Calculate the total electric field of an array from the embedded field, excitation amplitude, and phase shift of the individual antenna elements in the array. Use this calculated total electric field in the field analysis of the array using the pattern and EHfields functions.

R2023b: Perform field and port analysis on measured field data

Perform field and port analysis using pattern, EHfields, and sparameters on:

• The electric field and S-parameters data of an antenna

• The total electric field, embedded electric field, and S-parameters data of an array

measured at multiple frequencies.