2015 MATLAB & SIMULINK

2© 2015 The MathWorks, Inc.

Designing Antennas and Antenna Arrays

with MATLAB and Antenna Toolbox

Giorgia Zucchelli – Technical Marketing RF & Mixed-Signal

giorgia.zucchelli@mathworks.nl

3

Antenna and Antenna Array Modeling

Do you need to chose which antenna or antenna array to

use among many types, very diverse, infinite

configurations?

Do you need to estimate the impact of the antenna early in

your development cycle, and you are not an antenna

expert?

Do you need to integrate your antenna in your wireless

system and estimate its impact on the overall performance?

4

Wireless Systems are Everywhere and

Require Antennas

Radar

Communications (WiFi, LTE, Bluetooth, NFC, TV, …)

Medical

Spectral sensing

Digital

baseban

d

DAC RF

Digital

baseban

d

ADCRF

Transmitter

(TX)

Receiver (RX)

5

Why are Antennas Special?

Antennas are used at high frequencies to transmit and

receive electromagnetic waves

Antennas are distributed elements

The design requires specialized tools (“special case” of

microwave design)

6

What We Will Learn Today

Understanding basic antenna design fundamentals

Design antennas and arrays without being EM experts

Integrate antennas in phased-array algorithms

Model the entire end-to-end wireless system including

antennas

7

Antenna Toolbox DemoDesign and analysis of one antenna element, in just 5 lines of MATLAB code

>> p = patchMicrostrip

>> p.Height = 0.01

>> impedance(p, (500e6:10e6:2e9));

>> current(p, 1.66e9);

>> pattern(p, 1.66e9);

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Antenna Toolbox

Easy design

– Library of parameterized antenna elements

– Functionality for the design of linear and rectangular antenna

arrays

– No need for full CAD design

Rapid simulation setup

– Method of Moments field solver for port, field, and surface

analysis

– No need to be an EM expert

Seamless integration

– Model the antenna together with signal processing algorithms

– Rapid iteration of different antenna scenarios for radar and

communication systems design

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Analysis (and Visualization) of Antennas

Port

– Input Impedance, Resonance

– Reflection Coefficient, Return Loss

– Voltage Standing Wave Ratio (VSWR)

– Bandwidth

Surface

– Charge Distribution

– Current Distribution

Field

– Radiation Pattern, Beamwidth,

– E-Plane and H-Plane, Polarization

– Axial Ratio

10

Dipole antennas

– Dipole, Vee, Folded, Meander, Triangular bowtie, Rounded bowtie

Monopole antennas

– Monopole, Top hat, Inverted-F, inverted-L, Helix

Patch antennas

– Microstrip patch, PIFA

Spirals

– Equiangular, Archimedean

Loops

– Circular, rectangular

Backing structures

– Reflector and cavity

Other common antennas

– Yagi Uda, Slot, Vivaldi, Biquad

Antenna LibraryR2015b – 23 elements

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Custom Antenna Elements

Import 2D planar mesh

– E.g. design the antenna using PDE Toolbox

– Define the feeding point

– Analyse the antenna

– Build an array with custom elements

12

Build Your First Antenna Array

>> a = linearArray

>> a.Element = p;

>> a.ElementSpacing = 0.1;

>> a.NumElements = 4;

>> layout(a);

>> pattern(a, 1.66e9);

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Build More Complex Arrays

Customize homogeneous arrays

Manipulate each individual element of an array

– Rotation

– Size

– Tapering

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Optimization of Antenna Designatx_yagi_pattern_optimization

Yagi Antenna

Poor directivity at

90 deg

Optimization of pattern

Optimized pattern

15

Speeding Up Antenna Analysisatx_parallel_analysis

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What is Phased Array System Toolbox?

Algorithms and tools to design, simulate, and analyze

phased array signal processing systems

– Phased array design and analysis

– Waveform design and analysis

– Target, environment, platform models

– Temporal processing

– Spatial processing

– Space-time adaptive processing

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Modeling Antennas is Phased Arrays

Pattern multiplication of the isolated antenna pattern– Assume that each antenna is isolated: no coupling, no edge effects

...

% Import antenna element in Phased Array

myantenna = dipole;

myURA = phased.URA;

myURA.Element = myantenna;

Antenna

element

Phased

Array

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What if you Need to Take into Account …

Coupling effects in between antenna elements?

Edge effects?

The pattern multiplication of isolated elements is not sufficient

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Infinite Array Approach

Model the antenna as a unit cell of an infinite array

The ground plane specifies the dimensions of the cell

Determine the scan element impedance and pattern

– Function of frequency

– Function of scan angle

Compare to full-wave (if possible)

>> Suitable for very large arrays

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Embedded Element Pattern Approach

Compute the pattern of an antenna element when

embedded in an array

– All surrounding elements are terminated

Use pattern multiplication in your phased array

algorithm

>> Suitable for large arrays

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Phased Array Algorithms and Antennas

Analyse antenna arrays and experiment with:

– Phase shift (e.g. beamforming)

– Amplitude taper (e.g. windowing)

Integrate antenna effects in the simulation framework

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Integrating Antennas in RF, Communications

and Radar Systems

MATLAB / Simulink

Communications System Toolbox

Phased Array System Toolbox

SimRF

RF Toolbox

Data Acquisition Toolbox

Instrument Control Toolbox

Antenna Toolbox

RF

fro

nt-

end

Alg

orith

m

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From Bits to Antenna (and Back)

DSPLNA

PA

Antenna, Antenna arrays type of element, # elements, configuration

• Antenna Toolbox

• Phased Array System

Toolbox

Channel interference, clutter, noise

• Communications System Toolbox

• Phased Array System Toolbox

RF Impairmentsfrequency dependency, non-linearity, noise, mismatches

• SimRF

• RF

Toolbox

Waveforms

• Phased Array System Toolbox

• Signal Processing Toolbox

• Instrument Control Toolbox

Algorithmsbeamforming, beamsteering, MIMO

• Phased Array System Toolbox

• Communications System

Toolbox

• DSP System Toolbox

• Simulink (Simscape)

• DSP System Toolbox

• Control System

Toolbox

Mixed-SignalContinuous & discrete time

DACTX

RXADC

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What We Learned:

Use Antenna Toolbox to rapidly design antennas and arrays

without being an EM expert

– Geometry and configuration

– Port, surface and field performance

Integrate antennas in your algorithms with Phased Array

System Toolbox

– Beamforming

– Beam steering

Perform system simulation with Simulink and SimRF

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Conclusions

Antenna Toolbox

– Library of antenna elements, uniform linear and rectangular

array elements

– Don’t need to be an EM modeling expert to use the tool

Integration with other MATLAB toolboxes to speed up

array optimization, antenna tuning, and improve your

phased array and communications algorithms

The real advantage of Antenna Toolbox is that you can build,

analyze and visualize an antenna in just 5 lines of MATLAB Code.

This is hardly possible with any other tool.

Prof. Sergey Makarov, WPI

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More To Learn – Online Webinars

Designing Antennas and Antenna Arrays with MATLAB and Antenna

Toolbox

Phased Array System Toolbox Overview

Modeling and Simulating Radar Systems Using MATLAB and Simulink

Radar System Modeling and Simulation for Automotive Advanced

Driver Assistance Systems

Design and Verify RF Transceivers for Radar Systems