Shielding is a major means of EMI control at all levels of EMC. This chapter presents shielding theory, shielding materials, and some mathematical models of shielding effectiveness. The performance of shields is a function of whether the source appears as an electric or magnetic field in the near-in induction region or an electromagnetic field in the far-field region.

Chapter Contents:

• 6.1 Field Theory
• 6.2 Shielding Theory
• 6.2.1 Absorption Loss
• 6.2.2 Reflection Loss
• 6.2.3 Reflection Loss to Plane Waves
• 6.2.4 Reflection Loss to Electric and Magnetic Fields
• 6.2.5 Composite Absorption and Reflection Loss
• 6.3 Shielding Materials
• 6.4 EMI Shield Compartments and Equipments
• 6.5 Shielding Integrity Protection
• 6.5.1 Integrity of Shielding Configurations
• 6.5.2 EMC Gaskets
• 6.5.3 EMC Sealants
• 6.5.4 Conductive Grease
• Recommended Readings: EMI Shielding
• Web Addresses for EMI Shielding

Inspec keywords: electromagnetic shielding; electromagnetic compatibility

Other keywords: EMI control; shielding materials; EMC levels; magnetic field; shielding theory; electric field; mathematical models; electromagnetic field; near-in induction region; shielding effectiveness; far-field region; protection techniques

Subjects: Electromagnetic compatibility and interference; Electromagnetic waves: theory