Elektromagnetsband

Elektromagnetsband is a term used in physics and engineering to refer to ranges of electromagnetic frequencies, or bands in which electromagnetic waves interact with materials or structures in distinctive ways. In a broad sense, an electromagnetic band denotes a portion of the spectrum that shares similar propagation, absorption, or emission properties under given conditions.

In regulatory and communications contexts, the term often describes the division of the electromagnetic spectrum into bands assigned to specific services, such as radio, TV, mobile communications, and satellite links. Each band corresponds to a defined frequency range with particular technical requirements and usage rules.

In material science and wave physics, electromagnetics bands appear in the study of periodic media, such as photonic crystals and metamaterials. These structures can produce electromagnetic band gaps—frequency ranges where propagation is suppressed—alongside allowed bands where waves can travel. The position and width of these bands depend on geometry, material contrast, and polarization.

Applications of electromagnetics bands include the design of filters, antennas, waveguides, and shielding devices. Theoretical analyses often use band-structure concepts derived from Bloch theory, while practical work relies on numerical methods such as finite-difference time-domain (FDTD) simulations or plane-wave expansion. Experimental methods measure transmission and reflection spectra and map dispersion relations to identify band positions and gaps.

See also: electromagnetic spectrum, photonic crystal, metamaterial, band gap.