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  2. Mobile phones on aircraft - Wikipedia

    en.wikipedia.org/wiki/Mobile_phones_on_aircraft

    Mobile phones on aircraft. In the U.S., Federal Communications Commission (FCC) regulations prohibit the use of mobile phones aboard aircraft in flight. [1] Contrary to popular misconception, the Federal Aviation Administration (FAA) does not actually prohibit the use of personal electronic devices (including cell phones) on aircraft.

  3. Line-of-sight propagation - Wikipedia

    en.wikipedia.org/wiki/Line-of-sight_propagation

    Line-of-sight propagation is a characteristic of electromagnetic radiation or acoustic wave propagation which means waves can only travel in a direct visual path from the source to the receiver without obstacles. [1] Electromagnetic transmission includes light emissions traveling in a straight line. The rays or waves may be diffracted ...

  4. Radiation pattern - Wikipedia

    en.wikipedia.org/wiki/Radiation_pattern

    In the field of antenna design the term radiation pattern (or antenna pattern or far-field pattern) refers to the directional (angular) dependence of the strength of the radio waves from the antenna or other source. [1][2][3] Particularly in the fields of fiber optics, lasers, and integrated optics, the term radiation pattern may also be used ...

  5. Physics of optical holography - Wikipedia

    en.wikipedia.org/wiki/Physics_of_Optical_Holography

    When a plane wave is added to a point source and the resulting interference pattern recorded, a point source hologram is produced. This is effectively a Fresnel zone plate which acts as a lens. If the plane wave is normally incident on the recording plate, three waves are diffracted by the plate the original plane wave

  6. Non-line-of-sight propagation - Wikipedia

    en.wikipedia.org/wiki/Non-line-of-sight_propagation

    Non-line-of-sight (NLOS) radio propagation occurs outside of the typical line-of-sight (LOS) between the transmitter and receiver, such as in ground reflections. Near-line-of-sight (also NLOS) conditions refer to partial obstruction by a physical object present in the innermost Fresnel zone. Obstacles that commonly cause NLOS propagation ...

  7. Mobile telephony - Wikipedia

    en.wikipedia.org/wiki/Mobile_telephony

    Shut-off mobile phones do not interfere with aircraft avionics. The recommendation why phones should not be used during take-off and landing, even on planes that allow calls or messaging, is so that passengers pay attention to the crew for any possible accident situations, as most aircraft accidents happen on take-off and landing.

  8. Wireless device radiation and health - Wikipedia

    en.wikipedia.org/wiki/Wireless_device_radiation...

    v. t. e. The antennas contained in mobile phones, including smartphones, emit radiofrequency (RF) radiation (non-ionizing "radio waves" such as microwaves); the parts of the head or body nearest to the antenna can absorb this energy and convert it to heat. Since at least the 1990s, scientists have researched whether the now-ubiquitous radiation ...

  9. 2.4 GHz radio use - Wikipedia

    en.wikipedia.org/wiki/2.4_GHz_radio_use

    Using wired phones, which do not transmit. Using cordless phones that do not use the 2.4 GHz band. Using the 5 GHz band. DECT 6.0 (1.9 GHz), 5.8 GHz or 900 MHz phones, commonly available today, do not use the 2.4 GHz band and thus do not interfere. VoIP/Wi-Fi phones share the Wi-Fi base stations and participate in the Wi-Fi contention protocols.