Concerns mount over GPRS radiation emissions. The high emissions from GPRS could tar the whole industry. I wish the Europeans would kill it voluntarily.
1)New Scientist comments on need to lower bit rate of GPRS in order not to exceed radiation limits.
newscientist.com
TOO HOT TO HANDLE
By Barry Fox
Fears of radiation and overheating will slow
new cellphones
TRANSMISSION speeds from new GPRS
cellphones, due to be launched in Britain this
year, will be held down to keep them within
radiation absorption guidelines and to stop them
overheating, New Scientist has discovered.
Cellphone companies seem not to have learned
from their massive over-hyping of WAP services,
and risk crippling the fledgling market for GPRS by
making hollow promises about speed.
"We have known for ages about these
limitations," says Rainer Lischetzki of phone
maker Motorola. "We regret the sales talk and
data rate exaggeration."
With today's WAP phones you get a cut-down form
of Web access. But users have been turned off by
slow download speeds, and some phones' small
screens. Surfing is expensive because networks
charge by the minute for slowly downloaded
pages.
The new GPRS (General Packet Radio Service)
services are meant to provide a higher speed.
They will also charge per bit of data instead of per
minute, so you will only pay for what you
download. Even better, GPRS is an "always on"
service, so you will see e-mails instantly.
In two years' time, third-generation cellphone
systems will offer ultra-fast access. But cellphone
companies want people to upgrade to the
intermediate GPRS system in the meantime.
The GSM system now widespread in Europe uses
channels sliced into eight slots. Each slot is
allotted to a different phone and carries data at
9.6 kilobits per second--one-sixth the speed of a
PC modem. People are charged for the time they
use the slot.
GPRS lets users harness more than one available
slot. But while you could theoretically bunch
together four or five slots for GPRS reception,
handsets may overheat if they transmit on more
than one slot, causing circuits to burn out. Above
two slots, the phone's microwave radiation could
exceed European guidelines on the energy that
can be absorbed by the brain, says Lischetzki.
Early GPRS phones will only use one transmission
slot, with two slots for receiving. Later models will
move to four reception slots, boosting download
speeds, but they will stick with one transmission
slot to stay within emission guidelines. Single slot
transmission will avoid excessive heating and
battery drain, but will limit the speed of, for
example, video phone output.
Yet Motorola's website and briefing documents
promise speeds up to 171.2 kilobits per second
with "streaming and live video content". A press
statement from the network operator BT Cellnet
promises GPRS can "send and receive data up to
five times faster than is currently possible (and)
up to ten times faster in the coming months".
But according to Lischetzki, "The realistic
maximum rates we can get from GPRS are 64 kbps
into the handset and 30 kbps out." Privately, a BT
Cellnet engineer was even more conservative,
promising a best case scenario of 10 kbps
transmission and 40 kbps reception.
People who think GPRS will give desktop
multimedia will be sorely disappointed. Streaming
even low-quality MP3 hogs two whole slots. And
with that download capacity, videophones will
manage about two frames per second.
from New Scientist, 07 October 2000
2) Motorola quickly discredits its own spokesman with pleanty of "no comments"
Fri, 27 Oct 2000 11:13:05 GMT
Jane Wakefield
Motorola says New Scientist report on GPRS radiation safety was wrong but declines to explain
why
Mobile manufacturer Motorola is backtracking on recent comments by its spokesman suggesting
that GPRS, the high-speed successor to GSM, might have to be made slower in order to stay
within radiation absorption guidelines.
Motorola marketing manager Rainer Lischetzki recently told New Scientist that implementing
GPRS at the speeds its marketing division has hyped -- between 27Kbps and 86Kbps -- could
cause a phone to overheat. He also said such speeds could push a phone's microwave radiation
beyond European guidelines on the energy that can be absorbed by the brain.
But Motorola now says the New Scientist report was at fault, claiming that Lischetzki is not
"qualified" to discuss GPRS issues despite the fact that he is Motorola's technical marketing
manager for GPRS.
ZDNet's request for an interview with Lischetzki was refused. According to Motorola's director of
communications Mark Durrant the company is not prepared to risk "another inaccurate report".
Instead Motorola has issued as statement conceding that: "Whilst the initial GPRS phones that
enter the market may not operate at their highest theoretical data speeds, that fact is not related to
the issues raised by New Scientist." Motorola offers no explanation about why higher speeds will
not be available.
However the Department of Trade and Industry (DTI) confirmed that higher speeds could be
potentially dangerous. "It is conceivable that GPRS devices... could produce exposures above the
levels specified in the Council Recommendation," said a DTI spokesman.
Simon Mann, technical spokesman for the National Radiological Protection Board (NRPB) agrees,
saying that although mobile manufacturers will have to observe regulations governing the emissions
from mobile phones, it is "entirely feasible" that some GPRS mobiles, particularly those at the top
end of the market, could tip over the [emission] limits".
The issue revolves around whether or not GPRS mobile phones will operate at the speeds mobile
manufacturers are touting. Typically GPRS mobiles are hyped as transferring data at around three
to five times faster than current mobiles, although consensus suggests these speeds are
exaggerated.
Analogue mobile phones have a transmitter which is on all the time when making a call, with one
phone having exclusive use of one radio channel. GSM phones share channels, with up to eight
phones taking it in turns to transmit short bursts of data on a single channel. This means that
although a GSM phone has a maximum power output of two watts, in practice it transmits an
eighth of that -- quarter of a watt, maximum. This can and frequently is reduced still further.
To save battery life and to increase the number of phones that can be handled by the system, the
mobile's power is automatically adjusted to the minimum necessary to keep a reliable link with the
base station.
GPRS uses exactly the same system, but to increase the amount of data transferred a phone can
use more than one slot. Thus a three-slot GPRS link, carrying around 30 to 40kbps, will use a
maximum of three-quarters of a watt. This is roughly the same as an analogue phone used for a
single voice call, but as with GSM the power levels will often be lower than the maximum
especially in areas with a high density of base stations or a low density of buildings.
Average power levels are further reduced by GPRS being a packet-based system -- the transmitter
is only on when data is being sent and is idle otherwise. A file transfer from the phone to the base
station will make the transmitter work at full tilt -- keystrokes or Web browsing will only fire up the
transmitter occasionally, reducing the average power output to a few milliwatts.
When ZDNet eventually got to speak with Lischetzki, he said confusion over what speeds GPRS
would actually run at were damaging both for Motorola and for the mobile industry in general and
that his comments about the safety of GPRS mobiles were misconstrued. He offers no clarification
on theses comments.
Motorola's refusal to answer questions was condemned by the Consumers' Association. "Given the
concern among consumers about health issues and mobile phones, I think Motorola's actions are
unhelpful," said a spokeswoman. She added: "Clarity is needed on these issues. It's a topic of
concern for many consumers."
3) Another New Scientist article clains mobile phones disturb sleep
newscientist.com
MOBILE PHONE CALLS
LINGER IN THE MIND
By Duncan Graham-Rowe
Using a mobile phone before bed may disturb
your slumber
THAT late-night phone call to a loved one may be
comforting, but using a mobile phone just before
going to sleep may affect your brain activity for up
to three-quarters of an hour while you slumber,
according to Swiss researchers. "This study
demonstrates that a short exposure to
[electromagnetic fields] emitted by mobile phones
has an effect on brain physiology," say the
authors at the University of Zurich.
Alexander Borbély, Peter Achermann and their
colleagues attempted to simulate real-life
exposure. They subjected 16 people to
electromagnetic radiation on one side of their
heads for 30 minutes before going to bed. The
fields were tailored to simulate the signal from a
900-megahertz GSM phone, the most common
type of mobile in Europe. Once the subjects were
asleep, researchers monitored the electrical
activity in their brains.
Surprisingly, they found it made no difference
which side of the brain was exposed. "We
expected to see an asymmetry," Achermann
explains. But they did find that the subjects' brain
activity in early non-rapid-eye-movement sleep
increased significantly, and that the effects lasted
as long as 50 minutes (NeuroReport, vol 11, p
3321).
This deep non-REM sleep is characterised by a
repetitive pattern of brain activity known as sleep
spindles. Since only non-REM sleep is affected,
Achermann suggests that the organs that
generate spindles, such as the thalamus, may be
susceptible to the radiation in some way. "The
persistence of the effect would suggest it is
chemical rather than electrical," says Alan Preece
at the University of Bristol, who found last year
that mobile phone radiation can affect reaction
times.
from New Scientist, 14 October 2000
4)NeuroReport article on phisiological and psychologcal effects of radiation.
neuroreport.com
Press release
NeuroReport
Exposure to pulsed high-frequency
electromagnetic field during waking affects
human sleep EEG
Reto Huber, Thomas Graf, Kimberly A. Cote, Lutz Wittmann,
Eva Gallmann, Daniel Matter, Jürgen Schuderer, Niels Kuster,
Alexander A. Borbély and Peter Achermann
Contact: Dr Peter Achermann, Institute of Pharmacology and
Toxicology, University of Zürich, Winterthurerstrasse 190, CH-8057
Zürich, Switzerland
E-mail: acherman@pharma.unizh.ch
Related information: unizh.ch
NeuroReport Volume 11, number 15, 3321-3325
The aim of the study was to investigate whether the electromagnetic field emitted by digital
radiotelephone handsets affects brain physiology. The main effect was the enhancement of the intensity of
certain frequencies of the brain’s electrical signals (i.e. electroencephalogram, EEG) in the first 30
minutes of non-REM sleep.
The extensive use of mobile phones has given rise to public debate about possible adverse effects on
human health. A recent report of the Independent Expert Group on Mobile Phones established by the
British government summarized the relevant studies on the biological effects of electromagnetic fields
(EMF). They proposed that a precautionary approach be adopted until more robust scientific information
becomes available. In a previous study, the authors demonstrated that exposure to EMF during sleep
reduced waking after sleep onset and affected the EEG in non-rapid eye movement (non-REM) sleep.
In this present study, the authors investigated the effect of exposure to pulsed high-frequency EMF during
waking on subsequent sleep. Fields similar to those emitted by mobile communications equipment of
GSM type (global system for mobile communication) were applied. To simulate the real-life exposure
conditions, the subjects were exposed on either side of the head. The EMF was directed to either the
right or left side of the head for 30 min. The subsequent sleep episode was analyzed. As in a previous
study, in which mechanical stimulation of the right hand had been shown to induce unilateral changes in
the sleep EEG, the authors anticipated hemispheric differences.
Exposure to EMF affected neither the sleep stages, nor were significant effects of EMF exposure
observed for subjective assessment of waking after sleep onset, sleep latency, and sleep quality.
The main effect of EMF exposure was the enhancement of the intensity of the brain’s electrical signals
(EEG power density) in the frequency range of 9.750 - 11.25 Hz and in the 12.25 - 13.25 Hz in the first
30 minutes of non-REM sleep. This effect was also present when the left and right exposure were
analyzed separately. The two sides of the brain were similarly affected after left and right exposure. A
comparison within individuals showed that the spectral spindle peak frequency in the 10 - 15 Hz range
was not shifted by left and right exposure. The REM sleep spectrum was not significantly affected.
In this study the authors have shown for the first time that exposure to EMF during waking affects the
EEG during subsequent sleep. In the authors’ previous study, the EMF was directed towards the top of
the head to expose both sides of the brain. In the present experiment, the field was aimed at one side or
the other. Contrary to the authors’ expectation, the change in the brain’s electrical signal intensity was
similar for both sides of the head.
The present results lend support to previous reports on effects of EMF on physiological and
psychological variables. These include sleep and cognitive function as well as blood pressure and heart
rate. However, the present study is unique in having confirmed previous results of an experiment
performed under similar conditions on the effect on sleep. The other findings still need to be replicated
or could not be reproduced.
This study demonstrates that a short exposure to an electromagnetic field similar to those emitted by
mobile phones has an effect on brain physiology. Conclusions about possible adverse effects on human
health are premature because the underlying mechanisms are unknown. Further studies are needed to
determine the time course of the changes, to specify field strength - response relationships, and to define
the critical field parameters (e.g. modulation, frequency).
This paper and accompanying In Focus article by a journal editor is for a short period freely
available on-line on this site.
To obtain a faxed pre-publication copy of this paper please contact:
Dr Phil J. Daly or Mr Ian Burgess
NeuroReport Editorial Office
Tel: +44-(0)20-7940-7500 (switchboard), -7521 (PJD), or –7518 (IB)
Fax: +44-(0)20-7940-7515
E-mail: pdaly@lww.co.uk
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