Absorption loss

Before you can calculate shielding effectiveness, you need to know whether your material qualifies as a good conductor — and that's where loss tangent comes in. This deep dive connects the math to the physics, from plane wave propagation to practical near- and far-field shielding formulas.

Understanding how shields perform in the near field requires accounting for wave impedance differences between electric and magnetic sources. This sixth installment derives shielding effectiveness formulas for near-field conditions and reveals a surprising truth: copper outperforms steel at low frequencies, but steel's superior absorption reverses this advantage above 4kHz.

Discover why copper shields outperform steel at low frequencies but steel dominates at high frequencies. This practical guide presents simplified formulas for calculating electromagnetic shielding effectiveness, revealing the surprising crossover point at 4200 Hz where material performance flips.