Microwave classification and its absorption principle

- Mar 23, 2019-

Absorbing materials absorb electromagnetic waves (such as radar waves) by converting them into other forms of energy (such as heat) that are consumed. The creation of highly absorbent materials must follow the concept of physics (electrodynamics) and the physicochemical approach of matching to find the best mixture. The analysis shows that the non-uniform two-component and multi-component materials are the most promising, and the composition of the materials can be determined according to the electromagnetic and physicochemical properties of conductors, semiconductors and media. The electromagnetic energy absorbed by the material depends on its dielectric constant and permeability. In practical engineering applications, the total absorption is of the greatest interest. The absorption mechanism can be interpreted by complex expressions of the dielectric constant and the permeability.


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In the above equations, the real parts of the permittivity and the permeability are respectively expressed by the groups ofε'randμ'r The imaginary parts of the dielectric constant and the permeability are respectively expressed by the "r" and "" r. Absorption medium attenuates the electromagnetic wave passing through. The absorption energy model can be expressed in the complex form of reflection coefficient, relative dielectric constant or relative permeability. The imaginary part is the main factor that causes the energy absorption of the medium. The absorbed electromagnetic wave is converted into heat energy. Therefore, the average heat released in 1 second and 1 cubic centimeter of material is:


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