Radiated Emissions
Section 10: Environmental Qualification (DO-160)
Definition
Electromagnetic energy radiated into free space by the equipment or its associated wiring that may cause interference with aircraft radio systems or other electronic equipment. DO-160 Section 21 defines radiated emission limits measured at a specified distance from the equipment under test, covering the frequency range from 2 MHz to 6 GHz.
Where This Shows Up
Radiated emissions testing is performed in a shielded enclosure or open-area test site to measure the RF energy radiated by the equipment. The limits are set to prevent interference with aircraft communication and navigation receivers operating in protected frequency bands. Equipment with high-speed digital circuits, switching regulators, displays, or wireless interfaces requires careful attention to EMI design practices (filtering, shielding, grounding, layout) to meet radiated emission limits. Category M, the most commonly applied category for equipment installed inside the aircraft, includes protection of VHF, UHF, GPS, ILS, VOR, DME, and other aircraft receiver frequency bands.
Primary Sources
Section 21 (Emission of Radio Frequency Energy) — defines radiated emission test methods, limits, and protected frequency bands.
Related Terms
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