EMF Field Analyzer - Electromagnetic Pollution Monitoring

Overview

This project provides a comprehensive MATLAB-based toolkit for computing and visualizing electromagnetic fields generated by common sources of electromagnetic pollution (electrosmog). The simulations cover both Extremely Low Frequency (ELF) fields from power transmission lines and High Frequency (HF/RF) fields from radio antennas.

Project Structure

emf-field-analyzer/
│
├── powerlines_ELF_50Hz/          # Magnetic field B from power lines (50 Hz)
│   ├── single_wire/              # Single infinite conductor
│   ├── two_wires/                # Two parallel conductors
│   │   ├── in_phase/             # Currents in same direction
│   │   └── opposite_phase/       # Currents in opposite directions
│   └── three_phase/              # Three-phase power system
│       ├── in_phase/             # No phase shift (educational)
│       └── 120deg_shift/         # Real three-phase (120° shift)
│
├── antennas_HF_RF/               # Electric field E from antennas (HF/RF)
│   ├── isotropic/                # Ideal isotropic radiator (reference)
│   ├── yagi_uda_directive/       # Yagi-Uda antenna (TV, radio)
│   └── parabolic_dish/           # Parabolic antenna (satellite, microwave)
│
└── README.md
└── use cases
    ├── Three-Phase 380 kV Power Line
    ├── Mobile Base Station (GSM/LTE)

Physical Background

Magnetic Field from Power Lines (ELF)

Power transmission lines carry alternating current at 50 Hz (Europe) or 60 Hz (USA). The magnetic field B around an infinite straight conductor is given by the Biot-Savart law:

B = (μ₀ · I) / (2π · r)

Where:

• μ₀ = 4π × 10⁻⁷ H/m (permeability of free space)
• I = current magnitude [A]
• r = perpendicular distance from the wire [m]

The field decays as 1/r for a single wire, but for balanced three-phase systems, mutual cancellation causes the field to decay as 1/r², significantly reducing far-field exposure.

Electric Field from Antennas (HF/RF)

Radio frequency antennas generate electromagnetic waves. In the far-field region (r >> λ), the electric field magnitude is:

E = √(30 · EIRP) / r · F(θ,φ)

Where:

• EIRP = Equivalent Isotropically Radiated Power [W]
• r = distance from antenna [m]
• F(θ,φ) = normalized radiation pattern (antenna-specific)

Regulatory Limits

Italy - DPCM 8 July 2003

Magnetic Fields (50 Hz)

Level	Value	Application
Exposure limit	100 μT	Never to be exceeded
Attention value	10 μT	Areas with >4h daily presence
Quality objective	3 μT	New installations near sensitive areas

Electric Fields (100 kHz - 300 GHz)

Level	Value	Application
Exposure limit	20 V/m	Short-term exposure
Attention value	6 V/m	Prolonged exposure areas
Quality objective	6 V/m	New installations

International Guidelines (ICNIRP 2020)

• 50 Hz magnetic field: 200 μT (general public), 1000 μT (occupational)
• RF electric field (100 MHz): 28 V/m (general public)

How to Use

Each simulation folder contains:

1. simulation.m - MATLAB script (clean, executable code)
2. output.png - Pre-generated visualization
3. DESCRIPTION.txt - Detailed technical explanation

To run a simulation:

cd powerlines_ELF_50Hz/three_phase/120deg_shift/XY_plane
run simulation.m

Mathematical Formulations

Vector Superposition

For multiple sources, the total field is computed by vector addition:

B_total = Σ Bᵢ (vector sum)
|B_total| = √(Bₓ² + Bᵧ² + Bᵤ²)

Three-Phase Current Phasors

In a balanced three-phase system:

I₁ = I₀ · e^(j·0°)     = I₀
I₂ = I₀ · e^(j·120°)   = I₀(-½ + j√3/2)
I₃ = I₀ · e^(j·240°)   = I₀(-½ - j√3/2)

Key property: I₁ + I₂ + I₃ = 0 (phasor sum is zero)

Antenna Radiation Patterns

Antenna Type	Pattern F(θ,φ)	Characteristics
Isotropic	1	Uniform sphere (theoretical reference)
Short Dipole	sin(θ)	Toroidal, null along axis
Yagi-Uda	sin(θ)·sin(φ)	Directional lobes
Parabolic	cos²(θ)	Narrow pencil beam

Author

Federico Sabbadini

License

MIT License - See LICENSE

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Last updated: December 2024