Estimate skin depth, absorption loss, reflection loss, multiple-reflection correction, and aperture leakage for a uniform single-layer shield under a far-field plane-wave approximation.
Uses a far-field plane-wave, uniform single-layer shield approximation; apertures may control total shielding.
Enter the parameters and run the calculation to see results and model assumptions here.
Formulas, variables, and model boundaries are published. References last reviewed on 2026-08-30.
These equations directly produce the primary results and define the tool’s core model.
3δ = 1 / √(πfμσ) = 1 / √(πfμ₀μᵣσ)Characteristic depth at which field amplitude inside a conductor falls to 1/e of its surface value.
A = 8.686 · t / δAbsorption attenuation in dB produced by shield thickness t relative to skin depth.
R = 168 − 10·log₁₀(f·μᵣ/σᵣ)Reflection loss at the shield interface for a plane wave, where σᵣ = σ/σ_copper.
Derive units, levels, and supporting engineering quantities from the core values.
2MRC = 20·log₁₀(1 − 10^(−A/10))Correction for internal multiple reflections in a thin shield when A is small.
SE_pore ≈ 20·log₁₀(λ / (2·d_max))以最大开孔 d_max 得到远场单孔工程包络；min(本体 SE, 孔隙 SE) 仅是保守瓶颈估算，不是实际腔体的严格解。
Results use the models and assumptions shown on this page for design estimates and pre-compliance risk review. Complex structures, dispersion, near-field coupling, and test setup can cause significant deviation.
SE(dB) = 20·log₁₀(E_incident / E_transmitted). Via transmission-line theory it decomposes into absorption loss A, reflection loss R, and multiple-reflection correction B (Schelkunoff decomposition).
A(dB) = 8.686 · t / δ, with t the shield thickness and δ the skin depth at that frequency. Each additional skin depth adds about 8.7 dB of absorption.
At low frequencies reflection loss vanishes and skin depth is large (insufficient absorption); high-permeability materials (mu-metal, silicon steel) must divert the flux. Copper and aluminum are nearly useless for low-frequency H fields.
These tools support design-stage estimates. For accredited EMC testing, compliance decisions, and troubleshooting, contact us.