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A short explanation of common technical terms and abbreviations


Terms relating to non-ionising radiation
(ie radiation that won’t knock atoms into charged bits or ions)

EMF : electromagnetic field

EMR : electromagnetic radiation

RF : radio frequency

MW : (in our context) microwave

ELF : extremely low frequency (typically 1 to 300 Hz [Hertz or cycles per second])

Carrier frequency : the frequency of the microwaves that are shaped or modulated to carry information (eg 1200MHz = 1.2GHz is used by some GSM)

Pulse frequency : the frequency of data bursts from TDMA systems (eg 217Hz for GSM)

Hertz, or Hz = cycles per second, or the number of full wave forms arriving at a point per second, so represents frequency: ‘how often do waves arrive?’ (Wavelength? If more waves arrive at a higher frequency, the waves must be shorter, since they all travel at the same speed [speed of light]. So vice versa, as frequency decreases, wavelength increases.)

1 kHz = 1 kilo Hertz = 1,000 cycles per second

1 MHz = 1 mega Hertz = 1,000,000 cycles per second

1 GHz = 1 giga Hertz = 1,000,000,000 cycles per second


GSM transmits around 900 MHz = 900,000,000 cycles per second

UMTS transmits around 2.1 GHz = 2,100,000,000 cycles per second

therefore UMTS is a higher frequency and its wavelength is shorter.

Second rule of this: the lower the frequency the more penetrative the radiation is: TETRA at 400 MHz is more likely to go through you, UMTS at 1.2 GHz is more likely to be absorbed by you. And also perhaps easier to shield yourself from.

Mobile technology terms:

GSM : global system for mobility (2G or 2.5G phones, where G is for generation) a TDMA system

3G : also UMTS : universal mobile telephony standard, in the UK a WCDMA system

TETRA : TErrestrial TRunked RAdio, a TDMA system

WiFi : wireless computer connections

DECT : Digital Enhanced Cordless Telecommunications. A GSM (TDMA) standard for domestic and office wireless phones.

TDMA : Time Division Multiple Access (giving users time slots in turn)

CDMA : Code Division Multiple Access (giving people’s data packets codes to identify them in transit)

FDMA : Frequency Division Multiple Access (giving people different carrier frequencies so they can talk at once)

WDMA : Wideband Division Multiple Access (having a carrier frequency band so wide lots of people and data can be squeezed in at once on slightly different frequencies) – and combinations, like TDCMA to get even more out of systems


ES : Electrosensitivity

EHS : Electro-hypersensitivity

MND : motor neurone disease

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