Mobile microwave ovens on the information superhighway
From Eileen O’Connor:
National Express trials in-coach Wi-Fi
Information superhighway
By John Leyden
Published Friday 10th March 2006 10:01 GMT
http://www.theregister.co.uk/2006/03/10/coach_wi-fi_trial/
UK coach firm National Express has launched a trial which has seen Telabria’s mSystem mobile Wi-Fi hotspots installed on coaches between London and Cambridge.
The scheme means travellers on the National Express’s 010 London to Cambridge route will be able to access the internet on the move via their Wi-Fi enabled laptops, PDAs and other handheld devices, at no extra charge above their ticket price.
Each coach on the route will carry Telabria’s mSystem MobilAP-3G, a multi-radio system that combines an 802.11b/g access point with 3G data network backhaul. The kit, aimed at the public transport industry, offers net access at speeds of up to 300Kbps wherever there is 3G network coverage. The only difficulty might be opening up laptops and working comfortably on cramped commuter coaches.
National Express chief engineer Gerry Price said: “We are very excited about the potential of this trial and the benefits it will bring to our customers, particularly those on busy commuter routes who increasingly see the value of staying connected before they reach their place of work and after they leave. But it’s not just the business community who will benefit. Mobile communication is increasingly being seen as a pre-requisite by a wide variety of travellers on the move.”
While the National Express trial will provide internet access to passengers for free, the mSystem MobilAP-3G features integrated support for user authentication and billing, enabling operators to charge for net access.
3G data coverage is available to over 60 per cent of the UK population, with GPRS data coverage extending to over 95 per cent. UK mobile operators including T-Mobile and Vodafone are planning upgrades for existing 3G networks to HSDPA (High Speed Packet Download Access) during 2006, which will see download speeds increase to over 1.5 Mbps. Telabria expects to support HSDPA within the MobilAP product line later this year. ®
And again from Eileen:
Please see enclosed information in New Scientist with regards to excessive radiation in train carriages etc from use of mobile phones; I wonder what levels are reached in pop concerts and football grounds with tens of thousands of people using mobile phones. I attended a Paul McCartney concert in Birmingham; he was encouraging the crowd to text a message to the screen on the stage, the limits must have exceeded ICNIRP as we all know ICNIRP does not offer protection in the first place.
Eileen
Cellphone radiation “trapped” in train carriages
02 May 2002
New Scientist (Print Edition )
Ian Sample
Passengers on packed trains could unwittingly be exposed to electromagnetic fields far higher than those recommended under international guidelines. The problem? Hordes of commuters all using their mobile phones at the same time.
Tsuyoshi Hondou, a physicist from Tohoku University in Sendai, Japan, who is currently working at the Curie Institute in Paris, says Japanese commuter trains are often packed with people surfing the web on their mobile phones.
The trend spurred him to find out what effect this had on the
electromagnetic radiation in a train carriage. Starting with plans of a typical train carriage acquired from a Japanese train operator, Hondou worked out the ratio of window area to structural
metal for a typical carriage. He then used this to work out what proportion of the microwave radiation from the cellphones would be transmitted out of a carriage through the windows and how much would be reflected back inside. Hondou then calculated how microwaves from mobile phones distributed throughout a train carriage would add together, much like light from different lamps would increase the overall illumination in a room.
He found that when both reflection and the cumulative effect of the radio waves were taken into consideration, the resulting electromagnetic field in a train carriage could exceed the maximum exposure level recommended by the International Committee for Non-Ionising Radiation (ICNIRP). “It’s possible even if the train is not crowded,” Hondou told New Scientist.
Buses and elevators
For a standard train carriage, with a carrying capacity of 151 people,
Hondou’s calculations show that it is possible to exceed ICNIRP exposure limits if 30 people, each with a mobile phone that emits radio waves at a power of 0.4 watts, all use their phones at the same time. The peak power a mobile phone is allowed to produce is two watts.
Hondou says his findings point to what could become a new environmental issue, especially as new wireless devices and laptop “connections” come onto the market. He suggests train operators should take notice. “At the moment, we have no regulation on the use of mobile phones in areas where many people are together,” he says. The problem could also arise on buses and in some types of lifts (elevators), he adds.
Les Barclay, a radio engineering consultant who was part of the British government’s Stewart enquiry into mobile phones and health risks, is cautious over Hondou’s findings. While he concedes microwaves will bounce around inside carriages and boost field levels, the increase should be minimal, because power drops off a short distance away from each phone, he says.
But Hondou counters that the drop-off Barclay refers to is only realistic if the radio waves are not strongly reflected by the train’s walls.
Journal reference: Journal of the Physical Society of Japan (vol 71, p 432)
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