This calculator determines the specific absorption rate (SAR) and incident power density from the electric field, the conductivity of the material and its mass density. It helps evaluate the amount of RF energy absorbed by tissues or materials exposed to an electromagnetic field.
Valuable tool for electromagnetic safety engineers, biomedical researchers and RF equipment designers seeking to ensure compliance with radiation exposure limits.
Formulas
SAR = (σ × E²) / md
Incident power density = E² / 377
Explanation of formulas
- σ is the conductivity of the material in siemens per meter (S/m).
- E represents the electric field intensity (V/m).
- md is the mass density of the material (kg/m³).
- SAR indicates the power absorbed per unit mass (W/kg), while power density describes the incident energy per unit area (W/m²).
Calculation of the SAR for an electric field of 100 V/m
Input : σ = 1 S/m, E = 100 V/m, md = 1000 kg/m³
Output : SAR = 0.01 W/kg, Power density = 26.53 W/m²
Benefits and uses
- Allows you to verify compliance of RF devices with human exposure standards.
- Useful for security analysis of mobile phones and antennas.
- Practical for modeling the effects of electromagnetic fields on materials.
- Reference tool for engineers and researchers in applied electromagnetism.