Part of the Electronics glossary:

In mobile phones, a radiation shield is an accessory that serves to decrease the amount of radio frequency ( RF ) energy being absorbed by a mobile phone user. Mobile phones are wireless communications devices that use frequencies in the microwave band. Microwave energy can be absorbed by water and converted to heat energy.

There is growing concern, especially in Europe, about the potential for harm arising out of the effects of the absorbtion of mobile phone microwave radiation in the brain of the user. In particular, both the use of unidirectional aerials and their very close proximity with the cranium have been identified as special risks. It is suggested that a significant proportion (perhaps 40%) of the output of unidirectional aerials is absorbed by the head of the user; and that energy is concentrated around the aerial, which tends to be bare millimeters from the brain.

Mobile phones have been linked with a number of phenomena including short-term and long-term memory loss, increased blood pressure, and brain tumors.

Radiation shields, designed to clip around the body and aerial of mobile phones, absorb and/or reflect microwave energy. Manufacturers claim that the action of placing the user in what amounts to a radiation shadow, can diminish the quantity of radiation absorbed to perhaps 2% of the level of an unshielded phone.

Radio frequency energy limits for mobile phones are specified in international standards EN55022b & IEC1000-4-3. However, some current research suggests these standards may be inadequate and incomplete.

This was last updated in April 2005
Posted by: Margaret Rouse

Related Terms

Definitions

  • heat pump

    - A heat pump is a device that takes heat from one source and moves it to another location through electric or mechanical means. Heat pumps may be used either to heat or cool. Heat pump technologies ... (WhatIs.com)

  • integrated solar

    - Integrated solar is the inclusion of solar power technology as a part of original construction rather than as a separate module that is added later. Solar energy may be gathered thermally or throug... (WhatIs.com)

  • segmented memory

    - Segmented memory is a system of addressing computer memory, which may be physical or virtual and may be operating in real or protected mode. The segmented memory system was used to expand the 64KB... (WhatIs.com)

Glossaries

  • Electronics

    - Terms related to electronics, including definitions about electrical components and words and phrases about computers, laptops parts, digital cameras, televisions and home appliances.

  • Internet applications

    - This WhatIs.com glossary contains terms related to Internet applications, including definitions about Software as a Service (SaaS) delivery models and words and phrases about web sites, e-commerce ...

Ask a Question. Find an Answer.Powered by ITKnowledgeExchange.com

Ask An IT Question

Get answers from your peers on your most technical challenges

Ask Question

Tech TalkComment

Share
Comments

    Results

    Contribute to the conversation

    All fields are required. Comments will appear at the bottom of the article.