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Wireless sensor networks – a new hazard... |
We regularly receive emails from a company called IDTechEx.com - 'Research, Analysis and Events of Printed electronics, RFiD, Energy Harvesting and their Applications' on the subject of wireless sensor networks. Since we are journalists rather than scientists, we have been rather baffled by their message although we felt that it could present yet more hazards for the electrosensitive. To quote: One hundred years after Faraday, came that other European giant of electrical theory and experiment, Nikola Tesla, who also parted his hair down the middle. Faraday brought us the dc motor and much more besides: Tesla brought us the ac motor and much more besides. However, Tesla did most of his work in the USA and became an American citizen. In 1905 he foretold that we shall be communicating with hand held phones all over the world. Another hundred years onward and the progress towards that dream has been truly awesome. Yet it is only a first step to small devices communicating without human involvement and without those radio masts and their expensive and vulnerable cabling. Remember that cellphones like land lines went down during the Haiti earthquake. It is not just East Asian hackers take down our systems: they remain extremely vulnerable and that includes the internet with its hard-wired infrastructure. Just power outages from a volcano or an earthquake can take them down. Mimicking the way a message is passed through a crowd of people, so-called ad hoc networking of radio signals is on its way. In its most general form it is like a mesh, where anything can communicate with anything provide it is near enough and ready enough. Like people hearing and talking, mesh networking devices can both receive and transmit without infrastructure. For example, after three decades of development, we now see tens of millions of utility meters in large buildings communicating via these mesh networks using the inherently meshed ZigBee protocol and derivatives. Start up Meraki Networks connects 400,000 San Francisco residents to the internet via their Free the Net ad hoc networking project and others aim to replace the tangle of wires in the home with mesh networking. Wireless Sensor Networks WSN are machine to machine M2M mesh networks operating like the internet in that they are self organising and self healing. If one "node" is out of action, then the message eventually gets round by another means. Drop them from a helicopter: they do the rest because they are "self-calibrating". Little wonder that battlefield communications is a primary proving ground of WSN and they will be used to study thermal vents at intense pressure on the seabed because they tolerate node failure. We should like these new networks to handle huge amounts of data and be completely maintenance free so we can put them on a billion trees to monitor forest fires, seal them in the concrete of buildings or the metal of engines and even drop them on disaster areas such as oil spills to monitor every animal and slick and help to deal with them. The SNCF national rail system in France already finds that they survive well in rolling stock. They then go on to describe various problems in terms of interference, delay in transmitting messages, power storage etc before announcing a conference in Germany at the end of May that will pull together all current advances – "Energy Harvesting and Storage Europe/ Wireless Sensor Networks & RTLS Europe" in Munich. In due course, the new printed electronics, a revolution as significant as the microchip forty years ago, gives the prospect of memristor electronics mimicking the synapses of the human brain. This could mean even lower power consumption. We may have harvesting, electronics and sensors all printed on top of each other on plastic film or paper at very low cost and, where necessary, biodegradable and/ or transparent devices. For example, the nodes monitoring that oil slick and its trapped animals will decay into harmless material when their task is done. We therefore asked Dr Andrew Goldsworthy whether this development is a good thing or a bad thing? And whether we should be worrying about it or welcoming it? His comments are below: As I see it, this is a bad thing. In effect, every participating household or "node" acts as a mast capable of receiving and transmitting speech and information via microwaves to its neighbours. It can be very efficient at what it does, but everyone (including children) will be blanketed with yet another layer of modulated microwaves coming from all directions and each household will be irradiated continuously at close range from its own setup. It seems to be quite likely that it will lead to an increasing number of people suffering adverse effects on their health some of which may be irreversible.
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