Matlab Integrate Antenna

Antenna Integration and Deployment

Integrate designed antennas into RF systems -- impedance matching, data exchange via measuredAntenna, RF propagation/site planning, and SAR compliance -- using MATLAB Antenna Toolbox and RF Toolbox.

When to Use

Impedance matching

• Match an antenna to 50 ohm (or other impedance)

• Improve return loss or VSWR

• Design L, Pi, or Tee matching network

• Convert lumped matching to distributed (Richards transformation)

• Compare 2-element vs 3-element bandwidth

Measured antenna creation

• Create a measuredAntenna from pattern data or simulation

• Use an antenna with txsite/rxsite for propagation

• Import antenna data from CST (.ffs) or HFSS (.ffd)

• Steer a beam with phase shifts on a measured array

• Use a measuredAntenna as element in a larger array

RF propagation and site planning

• Compute signal strength, coverage, or path loss between sites

• Analyze SINR, interference, or frequency reuse

• Perform ray tracing for 5G/mmWave propagation

• Determine link budget or link closure

• Plan wireless network transmitter/receiver placement

SAR estimation

• Compute SAR from an antenna near or inside biological tissue

• Assess RF exposure compliance (FCC/ICNIRP limits)

• Model a birdcage coil for MRI SAR analysis

• Compute point SAR or mass-averaged SAR (1g/10g)

• Design an implantable antenna and estimate SAR

When NOT to Use

• Designing antenna elements or arrays (geometry, optimization) -- use matlab-design-antenna

• Reflector antennas, reflectarrays, installed antennas, or RCS -- use matlab-analyze-antenna-structures

Must-Follow Rules

Matching Networks

• Set CenterFrequency BEFORE LoadImpedance for frequency-dependent loads -- errors otherwise

• Property is Bandwidth not BandWidth -- case-sensitive

• addEvaluationParameter requires all 5 args: parameter, comparison, targetdB, band, weight

• Prefer sparameters(ant, freqRange) as load over raw antenna object (avoids repeated EM solves)

• Default to Components = 2 unless fractional BW > 5% (then use 3)

Measured Antennas

• Always transpose after meshgrid for az-fast ordering -- silently wrong patterns otherwise

• txsite/rxsite require E = [] -- errors if E-field data is present

• Only patternMultiply works when measuredAntenna is the Element of an array (not pattern)

• CalculateTotalField = true is required for EmbeddedE workflow

• EHfields returns 3-by-P -- transpose to P-by-3 for measuredAntenna

RF Propagation

• Do not call show(tx) in headless environments -- use analysis functions directly

• sigstrength(rxArray, txArray, pm) returns numTX-by-numRX matrix

• pathloss with ray tracing returns cell arrays -- sum powers in linear domain

• SurfaceMaterial is for cartesian scenes; BuildingsMaterial/TerrainMaterial for geographic

• Ray tracing requires buildings or scene data -- no value without geometry

SAR

• EHfields expects 3-by-M -- pass obsPoints'

• dielectric class enforces LossTangent <= 0.03 -- only birdcage.Phantom and direct EHfields bypass

• Always validate SAR with power balance check (efficiency vs SAR integral)

• Always normalize to a known input power (typically 1W accepted)

• conformalArray rejects intersecting geometries -- cannot place antenna inside tissue

Workflow

1. Impedance Matching

1. Parse -- Identify load (antenna, impedance, file), frequency, bandwidth, topology

2. Create -- Set CenterFrequency FIRST, then LoadImpedance, Bandwidth, Components

3. Evaluate -- addEvaluationParameter for gammain or Gt goals

4. Inspect -- circuitDescriptions returns ranked candidates

5. Visualize -- rfplot (S11/gain), smithplot (impedance transformation)

6. Export -- exportCircuits for RF Toolbox circuit; richards for distributed elements

2. Measured Antenna Creation

1. Parse -- Identify source antenna/array, frequency, intended use case

2. Select workflow -- E-field, Directivity-only, EmbeddedE, element-in-array, or ffsReader

3. Generate grid -- Spherical grid with correct transpose for az-fast ordering

4. Extract data -- EHfields (3-by-P, transpose to P-by-3) or pattern (el-by-az, transpose)

5. Build -- Construct measuredAntenna with correct property combination

6. Verify -- Compare pattern against original antenna/array

3. RF Propagation & Site Planning

1. Parse -- Identify analysis type (coverage, SINR, ray tracing, link budget), frequency, environment

2. Create sites -- txsite/rxsite with location, antenna, frequency, power

3. Select model -- Choose propagation model based on environment

4. Analyze -- sigstrength, coverage, sinr, raytrace, or los

5. Report -- Signal strength (dBm), path loss (dB), SINR (dB), link margin

4. SAR Estimation

1. Select approach -- birdcage+Phantom, conformalArray+Custom3D, or direct EHfields

2. Build tissue model -- Phantom struct, shape.Custom3D with catalog material, or post-processing

3. Compute E-fields -- EHfields(ant, freq, obsPoints') (3-by-M format)

4. Calculate SAR -- Apply formula with tissue sigma and rho; normalize to input power

5. Validate -- Power balance check (efficiency method vs SAR integral)

Key Classes

Conventions

Coding Standards

• 4-space indentation, lowerCamelCase variables, UpperCamelCase Name-Value args

• "double quotes" for strings, fprintf for formatted output

• Do not add titles to Antenna Toolbox plots (pattern, show, rfplot, smithplot)

• Do add titles to manual plot, scatter3, imagesc figures

• Do not call show(tx) without siteviewer in headless environments

• Show all plots in separate figures. Include units in all output.

Script-First Workflow

For design, analysis, or sweep tasks -- write code to .m files, run via run_matlab_file, iterate by editing and re-running. Use inline evaluate_matlab_code for quick one-off checks.

References

Copyright 2026 The MathWorks, Inc.