Electromagnetic Interference Suppression and Electromagnetic Absorption

Electromagnetic interference (EMI) severely affects the operation of electronic equipment, either when the noise is generated by the device itself, or when it is received from the environment. Ferrites play a special part in protecting electronics from EMI and providing electromagnetic compatibility. This chapter first explains the physics of interaction of ferrites with RF and microwave electromagnetic fields and energy absorption, and then explores electromagnetic parameters of ferrites. It also discusses types of dispersion in ferrite materials and approximations of dispersion curves obtained from the Landau‐Lifshitz magnetization motion equation with different relaxation terms. Next, the chapter explains physics of electromagnetic energy absorption and factors determining the shape of magnetic spectra in ferrites. Currently, radar absorbers based on metamaterials have been attracting great interest. These absorbers can be considered as metamaterial‐based absorbers and FSS‐based absorbers. The chapter explains characteristics of radar absorbers and properties of absorber materials containing ferrites.