Wireless Charging

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Wireless Charging or Power Routers:

Battery Charging by radiation

Since about 2015 there have been several attempts to use radiation or wireless charging to supply electric energy to batteries in portable devices, such as cellphones and tablets.

A typical charger emits two types of radiation.

(1) Communication links, typically Bluetooth at 2.45 GHz, a wifi band.

(2) Power radiation:
Energous WattUp radiation devices at 5.850-5.875 GHz, just outside the 5.8GHz wifi band;
Apple propose 2.45 and 5 GHz wifi, 700 and 2,700 MHz and 60 GHz .

The U.S. Federal Communications Commission (FCC) approved on December 26 2017 a power-at-a-distance wireless charging certification to the WattUp Mid Field transmitter or Power Router. This charges mobile devices at a distance of up 15 feet (5m) in radius, or 30 feet (10m) in diameter. A safety barrier of 10 cm is the recommended test distance for “typical desktop applications”, per FCC heating guidelines for RF devices.

Health Dangers from wireless charging

  • Like all forms of electromagnetic radiation, wireless charging can adversely affect the human body.
  • How dangerous wireless charging is depends on the amount of energy being radiated and the distance from the device.
  • See Safety Limits to ensure that it complies with international biological standards. The danger is not heating by one degree over six minutes, a mistaken hypothesis proposed by Schwan in 1953, but the established biological effects at lower levels. Some top scientists state that any level of radiation above natural levels is harmful.
  • Key danger points include:

    (1) Length of time in the radiation zone:
    Ensure the device is switched off, including the Bluetooth communication link, unless required for under six minutes (the international heating limit).

    (2) Distance from the radiation device:
    Ensure that you keep outside the danger area within the radiation zone; see Safety Limits.

    (3) Sensitive people:
    Ensure that no sensitive people, such as children, pregnant women, people with EHS, the elderly or those with inflammatory conditions, are within the danger zone.

    (4) Location within the danger zone:

    Do not sit or stand between the device being charged and the radiating charger, since this will have the greatest energy fields.