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Wireless & Mobility · Foundational

Electromagnetic Wave

A self-propagating wave of oscillating electric and magnetic fields traveling at the speed of light.

Definition

An electromagnetic wave consists of electric and magnetic fields perpendicular to each other and to the direction of travel. It needs no medium and travels at about 300,000 km per second in a vacuum. Radio waves, light, and X-rays are all electromagnetic waves that differ only in frequency.

Exam tip

The orientation of the electric field defines antenna polarization, a frequent CWNA tie-in.

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