Location dependent computing - Wireless PDA

[MerrionComputin]

OK - it's total vapourware at the moment but there's a RFT for a project that allows a wireless PDA (probably 801.1b) to act as an information guide for an art gallery - listing additional information about particular paintings etc.
However, ideally the content should change as the user walks around such that they are presented with info pertinent to the section they are in (granularity ~1m).
Is this feasible - I can't think of how the PDA would know where it is - GPRS is out, as that would add too much hardware cost.

Any ideas?

[scostell]

Maybe something along the lines of bluetooth could help you out? Say have a laptop(or some CPU) in each station that supports bluetooth....So when the PDA enters the station it will communiate with the CPU thru bluetooth software.

Now I've never done anything like this, and am not really sure how blue tooth works. But from my initial understanding of the technology, this solution my be feasable.

[Cander]

You are going to need some kind of device by each painting that sends out some kind of data that the PDA can pick up on.

[CyberSurfer]

That's Context Aware Computing....one of the lecturers at the University of Kent where I happen to occasionally go to get drunk researches this very topic, but in relation to a mobile fieldwork / archaeology slant. His research page is here...http://www.cs.ukc.ac.uk/people/staff/nsr/mobicomp/

[MerrionComputin]

Cool stuff.

Anyway - it is possible to send out an enquiry frame which all the base stations respond to. By comparing the signal strengths of the returned frames it is possible to list the relative signal strengths of the base statiosn and thus (using a bit of trig and lookup tables on other factors of signal attenuation) the location of the PDA.