A high-intensity radiated field (HIRF) is

radio-frequency Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upp ...

energy of a strength sufficient to adversely affect either a living organism or the performance of a device subjected to it. A

microwave oven A microwave oven (commonly referred to as a microwave) is an electric oven that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range. This induces polar molecules in the food to rotate and produce ...

is an example of this principle put to controlled, safe use. Radio-frequency (RF) energy is non-ionizing electromagnetic radiation – its effects on tissue are through heating. Electronic components are affected via rectification of the RF and a corresponding shift in the bias points of the components in the field. The

U.S. Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food ...

(FDA), and U.S.

Federal Communications Commission The Federal Communications Commission (FCC) is an independent agency of the United States federal government that regulates communications by radio, television, wire, satellite, and cable across the United States. The FCC maintains jurisdicti ...

(FCC) set limits for the amounts of RF energy exposure permitted in a standard work-day.

History

The U.S.

Federal Aviation Administration The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic ...

(FAA) and industry EMC leaders have periodically met to define the adequacy of protection requirements for civil avionics from outside interference since 1980. In 1986 The FAA Technical Center contracted for a definition of the electromagnetic environment for civil aviation. This study was performed by the Electromagnetic Compatibility Analysis Center (ECAC). The study has shown levels of exposure to this threat as high as four orders of magnitude (10000 times) higher than the then current civil aircraft EMC susceptibility test certification standards of 1 volt/meter (DO-160). This environment was also two orders of magnitude higher (100 times) than the then prevailing military avionics systems test standards ( MIL-STD 461/462).

Units of measurement

An RF electromagnetic wave has both an

electric Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by ...

and a magnetic component (electric field and magnetic field), and it is often convenient to express the intensity of the RF environment at a given location in terms of units specific to each component. For example, the unit "volts per meter" (V/m) is used to express the strength of the electric field (electric "field strength"), and the unit "amperes per meter" (A/m) is used to express the strength of the magnetic field (magnetic "field strength"). Another commonly used unit for characterizing the total electromagnetic field is "power density." Power density is most appropriately used when the point of measurement is far enough away from an antenna to be located in the "far-field" zone of the antenna.

References

Bibliography

* * {{DEFAULTSORT:Hirf Radiation effects

History

Units of measurement

See also

References

Bibliography