EMC Engineering Services:
Shielding Effectiveness, Reflection & Scattering
RTL performs shielding effectiveness, penetration depth, reflection, and scattering on various materials. We have tested numerous materials used for cellular phone tower ascetics. We have designed automated fixtures to various test materials from DC to 220 GHz. RTL performs Shielding Effectiveness to the following standards:

• MIL-STD 285
• NSA 65-6
• IEEE 299

Shielding Effectiveness:
When a given electric field strength impinges on a shield barrier at a particular frequency, the wave current is induced into the barrier. This current is reduced by the barrier's skin effect as the wave penetrates the barrier. The ratio of the wave that penetrates the barrier and the incident wave on the barrier is the Shielding Effectiveness of the barrier.

Penetration:
Penetration depth is equal to the reciprocal of Shielding Effectiveness.

Reflection:
Reflection is when part of an electromagnetic incident wave that impinges on a material surface returns to its original source.

Scattering:
Scattering occurs when part of an electromagnetic wave that results when a transmitted wave encounters one or more discrete objects, a rough boundary between two medium or a continuous irregularities in the complex permittivity of the encountered medium.