In the concrete canyons of city centres, GPS satellite positioning systems often fail because high buildings block the signals they rely on. But an unlikely back-up for GPS is emerging: Wi-Fi. A Wi-Fi based positioning system developed in the US and the UK works best where GPS fails: in cities and inside cavernous complexes like shopping malls. And because cheap Wi-Fi technology is already appearing on a raft of gadgets like PDAs, cellphones and laptops faster than more expensive GPS receivers are, the developers predict that Wi-Fi could become central to new location-based applications.
They say emergency services in particular could find the system an essential back-up. Wi-Fi allows people to connect devices wirelessly to the internet. Base stations are springing up in coffee bars, libraries, universities, airports, phone booths and other public places. Each base station broadcasts a radio signal to announce its presence to devices within a range of around 100 metres. This signal incorporates a unique network address code that identifies the base station. Anthony LaMarca of the University of Washington in Seattle, and colleagues at Intel’s research labs in both the US and the UK, have developed software that constantly records the radio signal strengths from nearby base stations. It can identify the origin of the signal from a database giving the location of 26,000 Wi-Fi base stations in the US and the UK. Using the signal strength from at least three base stations, it can then triangulate the user’s location. "This is a poor man’s GPS," says team member Bill Schilit of Intel Research in Santa Clara, California.
At the moment, the new system, called Place Lab, is not as precise as GPS. It can provide accuracy to within 20 to 30 metres, whereas the GPS average is 8 to 10 metres. But with improved algorithms that take into account, say, the height of the base station above the ground, or the building materials in the vicinity, LaMarca says "we could get on a par with GPS" in an area as densely served with Wi-Fi as downtown Seattle. The growth of Wi-Fi means all urban areas should one day have similar blanket coverage. Once a user has Wi-Fi they won’t have to buy extra hardware to use Place Lab, and the software can be downloaded for free from http://www.placelab.org. Increasingly, laptops, cellphones and PDAs are being sold with Wi-Fi capability already installed for around an extra $30. "This is not the case with GPS," LaMarca points out.
Next Generation Cryptography
20.03.2018 | Fraunhofer-Institut für Sichere Informationstechnologie SIT
TIB’s Visual Analytics Research Group to develop methods for person detection and visualisation
19.03.2018 | Technische Informationsbibliothek (TIB)
Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.
The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...
An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.
The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...
In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.
Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
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