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Forget GPS, Hello WPS
No France writes "A company known as skyhook wireless has announced the commercial availability of its Wi-Fi Positioning System, or WPS. The company has compiled a database of every wireless access point it can find in a given city. When a mobile user running th Skyhook client is in a recorded area, their position is calculated by selecting the surrounding signals and comparing them to the reference database. Currently there are 25 US cities mapped, including New York City, Boston, Chicago, Los Angeles and San Francisco. Apparently this device is accurate to within 20-40 meters, though one has to wonder how well it deals with people moving their wireless access points."
They might as well give everybody a peice of paper with a huge X on it that says 'You are here'.
20 - 40 meters? Who will be forgetting GPS with that kind of crappy accuracy?
PlaceLab has been doing this for a while, and it's free.
Martin May
Apparently this device is accurate to within 20-40 meters
Hell, I can guess where I am to that accuracy. I thought GPSs where accurate within 5-8 meters nowadays. And this sounds really useful out in the open ocean, you know, where all those rouge wireless access points hang out.
Measure once, cut twice
Cities are the one place a positioning system is useless, so why develop it there?
You haven't tried to find a specific place in Tokyo or Osaka, have you?
Having a Gps is a life saver. You look up the place you want to go to on an online map, get the coordinates, and you're set. Without it, it's just too easy to miss the right building, mistake streets for each other or get lost in many other creative ways.
You could argue the other way round (and just as stupidly) - since there's one single highway or road in the entire area, why would you need a Gps to know which one you're on?
Trust the Computer. The Computer is your friend.
. . . but I suspect ultimately of little practical value. Having done quite a bit of RF scanning on the WiFi bands in one of their listed cities (San Francisco) I've seen first hand how signals behave in that dense urban environment.
GPS and WAAS operate on time signals and highly accurate positioning. Cell towers would be inherently more accurate since thier positions are accurately known and don't change (except under very unusual circumstances.
WiFi nodes come up and down constantly, and their position is rarely going to be accurately known by anyone but the person who installed it - and chances are they're not telling "you" exactly where the node is.
Given "walk around surveying" to map the nodes, it's not really a surprise they have accuracy that's no better than an early 2 channel GPS receiver.
And, as others have pointed out, if I'm in downtown San Francisco (or any other city) I don't need my GPS to tell me I'm at 5th and Townsend. For directions there's Mapquest, Google, Yahoo Maps, etc...
Interesting technology. But it sounds more like something a hobbiest would come up with than business.
Never attribute to malice what can as easily be the result of incompetence...
Basically, the military figured out how to easily jam GPS in an area. But before then, there were GPS field units available that averaged out the error and got better than 2-3 meters so that it didn't really matter that much...
Don't these people realize how accurate GPS positioning has become?
MGIS-grade equipment can now give positions with sub-foot ( 30cm) postprocessed accuracy. Survey-grade equipment can get within 5-10 cm.
As neat as WPS sounds, I don't think that anyone will be giving up GPS soon if WPS can't get any more accurate than 20-40 meters.
"Equal bytes for women!"
To be honest, I don't care how novel their ideas are. Using a system where position is located based on such arbitrary measurements is not only silly, but a waste of time. Not only can anyone move the access points around, but as they get shut off or more get added it will only make things worse. Also considering it can be influenced by minute things like weather and the position of the microwave in the apartment across the street make it a waste of time. You'd need to rescan it at least monthly to maintain even 20-40 feet (screw that) accuracy.
Let's see, a near-absolute positioning system based on immobile and unchanging (or extremely slowly) data, or something based on what could probably be described as a chaotic system? Not to be a jerk about it, but "Forget GPS"? More like "Ignore WPS".
"What do you despise? By this are you truly known." --Princess Irulan, Manual of Muad'Dib
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I'm worried less about privacy, and more about how I'm going to tape my wireless access point to my roomba just to mess with them.
But then, with such poor accuracy, it's not like anyone will be worried about 40 or 50 feet here and there.
Or, are any of my friends within 6 blocks of me?
They only way a free AP sponsor would be interested if any of your friends are within 6 blocks would be to suggest you all meet at Starbucks.
The truth shall set you free!
20-40 ft? This is totally useless for street navigation, surveying, etc.
What this is useful for is grander scale positioning without the need for a GPS device built into a portable device.
For example, timezones are far larger than 20-40ft. Laptops could be configured to automatically adjust the timezone setting to match the closest access points, no GPS device needed. A weather monitor utility could always automatically show the local weather. A star map could be configured to show the local sky. I'm sure many people can think of others.
http://brandonbloom.name
Yes, but my iPaq has Wi-Fi not GPS. And the screen can show a good map.
I could ensure I'm always carrying a GPS reciever or just a city map but you know what, I own both these and only carry them when I know I need them. Which in the case of GPS, is never.
The client software running on the tracked device measures the signal strength of the access points, forwards the data to the server which calculates the position. The big-brother scenario is avoided as long as you still have to install the client yourself.
The major drawback of the system is that it needs extensive calibration, since they are using not only the available access points, but also the signal strength of these. Normally they suggest calibration in a 5x5m (15x15ft) grid. More calibration points yield a more accurate result.
And now the piece of information you have all been waiting for: accuracy. With a good calibration this can yield accuracies of arround 1m. In my tests (indoor) the accuracies fluctuate a bit, but is at least better than 3m 95% of the time.
Just as the system described in the original post, Ekahau requires no extra hardware (we already have 2-300 APs on campus).
Can't you triangulate from FM radio station signal strength?
It woud have the following advangates:
Way smaller database
Way more coverage
It should be easy to do with the adevnt of software radio.
The only down side, is that you wouldn't need this company anymore!
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.