Microwave auditory effect

The microwave auditory effect, also known as the microwave hearing effect or the Frey effect, consists of audible clicks (or, with speech modulation, spoken words) induced by pulsed/modulated microwave frequencies. The clicks are generated directly inside the human head without the need of any receiving electronic device. The effect was first reported by persons working in the vicinity of radar transponders during World War II. These induced sounds are not audible to other people nearby. The microwave auditory effect was later discovered to be inducible with shorter-wavelength portions of the electromagnetic spectrum. During the Cold War era, the American neuroscientist Allan H. Frey studied this phenomenon and was the first to publish[1] information on the nature of the microwave auditory effect.

Pulsed microwave radiation can be heard by some workers; the irradiated personnel perceive auditory sensations of clicking or buzzing. The cause is thought to be thermoelastic expansion of portions of auditory apparatus.[2] The auditory system response occurs at least from 200 MHz to at least 3 GHz. In the tests, repetition rate of 50 Hz was used, with pulse width between 10–70 microseconds. The perceived loudness was found to be linked to the peak power density instead of average power density. At 1.245 GHz, the peak power density for perception was below 80 mW/cm2. However, competing theories explain the results of interferometric holography tests differently.[3]

In 2003-2004, the WaveBand Corp. had a contract from the US Navy for the design an MAE system they called MEDUSA (Mob Excess Deterrent Using Silent Audio) intended to remotely, temporarily incapacitate personnel. The project was cancelled in 2005.[4][5][6]

Primary Cold War-era research in the US

The first American to publish on the microwave hearing effect was Allan H. Frey, in 1961. In his experiments, the subjects were discovered to be able to hear appropriately pulsed microwave radiation, from a distance of 100 meters from the transmitter. This was accompanied by side effects such as dizziness, headaches, and a pins and needles sensation.

A decade later, an overview, in the American Psychologist, of radiation impacts on human perceptions, cites investigations at the Walter Reed Army Institute of Research that demonstrated 'receiverless' wireless voice transmission: "Appropriate modulation of microwave energy can result in direct 'wireless' and 'receiverless' communication of speech."[7]

Peaceful applications

A 1998 patent describes a device that can scare off birds from wind turbines, aircraft, and other sensitive installations by way of microwave energy pulses. Using frequencies from 1 GHz to about 40 GHz, the warning system generates pulses of milliseconds duration, which are claimed to be sensed by the birds' auditory systems. It is believed this may cause them to veer away from the protected object.[8]

As stated by the above-mentioned journal entry to the American Psychologist, "the averaged densities of energy required to transmit longer messages would approach the current 10mW/cm² limit of safe exposure", which makes the technology improper for human telecommunication. For this very same 'receiverless' wireless sound transmission to human beings, sound from ultrasound is used instead.

Conspiracy theories

Numerous individuals alleged to be suffering from auditory hallucinations, delusional disorders[9] or other mental illness have alleged that government agents use microwave signals to transmit sounds and thoughts into their heads as a form of electronic harassment, referring to the technology as "voice to skull" or "V2K".[10] There are extensive online support networks and numerous websites maintained by people fearing mind control. California psychiatrist Alan Drucker has identified evidence of delusional disorders on many of these websites[9] and other psychologists are divided over whether such sites negatively reinforce mental troubles or act as a form of group cognitive therapy.[11]

See also

Notes

  1. ↑ Allan H. Frey (1962). "Human auditory system response to modulated electromagnetic energy". Journal of Applied Physiology 17 (4): 689–692. PMID 13895081. Retrieved 21 August 2011.
  2. ↑ Levy, Barry S.; Wagner, Gregory R.; Rest, Kathleen M. (2005). Preventing occupational disease and injury. American Public Health Association. p. 428. ISBN 978-0-87553-043-7.
  3. ↑ http://www.sciencemag.org/content/209/4461/1144.extract?sid=f514230e-1373-4da5-ad36-3689f428e21b
  4. ↑ Taylor, Eldon (15 April 2009). Mind Programming: From Persuasion and Brainwashing, to Self-Help and Practical Metaphysics. Hay House, Inc. pp. 100–101. ISBN 978-1-4019-2513-0.
  5. ↑ "Navy search database – summary report: Remote Personnel Incapacitation System". SBIR/STTR Search Database (Small Business Innovation Research/Small Business Technology Transfer). U.S. Navy. Retrieved 12 January 2014.
  6. ↑ Hambling, David (3 July 2008). "Microwave ray gun controls crowds with noise". NewScientist. Retrieved 12 January 2014.
  7. ↑ D.R. Justesen. "Microwaves and Behavior", Am Psychologist, 392(Mar): 391–401, 1975.
  8. ↑ Kreithen ML. Patent #5774088 “Method and system for warning birds of hazards” USPTO granted 30 June 1998
  9. ↑ 9.0 9.1 Monroe, Angela (November 12, 2012). "Electronic Harassment: Voices in My Mind". KMIR News. Retrieved 2014-02-25.
  10. ↑ Weinberger, Sharon (January 14, 2007). "Mind Games". Washington Post. Retrieved 12 January 2014.
  11. ↑ Kershaw, Sarah (November 12, 2008). "Sharing Their Demons on the Web". New York Times.

References

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