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UCSD Students Tracking Their Friends' Locations

Posted by timothy on from the after-my-own-heart dept.

An Anonymous Coward writes: "The location-tracking software, developed by a 15-year-old student at the university, draws upon triangulation technology. The PDAs figure out their locations by comparing the strength levels of signals traveling from the devices to various Wi-Fi antennas. No GPS Required. Article from Salon here..."

2 of 246 comments (clear)

  1. PDAs by iofire · · Score: 5, Interesting

    I am one of those CS students who receieved a free PDA and I've never seen anyone do anything other than goof around on the internet in lecture with them.

    We did however make use of another app called activeclass that was semi-interesting, allowing students to post quetions to the professor during lecture (moderated by a TA). Unfortunately it tended to take so long to input the question on the PocketPC PDAs (which I find to be clunky and sluggish, I ended up giving my PDA to a family member to use) that the question was no longer relevant by the time I entered it.

    you can read about it here:
    http://activecampus.ucsd.edu/

    --
    --Avoid metagame thinking, browse with scores hidden (This sig is in violation of itself)
  2. Salon goof by plover · · Score: 5, Interesting
    When you consider that they probably have WiFi access points on just about every floor, it's pretty easy to say "within a margin of error of one floor."

    This sounds similar to the triangulation the cell phone companies tried to use to locate phones when ordered to do so by law enforcement (to comply with CALEA and ostensibly E-911.) That didn't work well enough in rural cell areas, however, thus the move to on-board GPS receivers in cell phones.

    The thing that amused me the most was the error in the Salon article's description of the technology involved:

    The location-tracking software itself, developed by a 15-year-old student at the university, draws upon triangulation technology used by global positioning system (GPS) devices. The PDAs figure out their locations by comparing the strength levels of signals traveling from the devices to various Wi-Fi antennas.

    GPS does not use signal strength. GPS uses differential timing. This system and software work like a GPS in the same way that a kitchen stove works like a microwave oven. Love them Salon facts.

    --
    John