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The raw data required comes from a gps receiver and correlated with power output readings from a wifi card. This can be recorded The raw data required comes from a gps receiver and correlated with power
output readings from a wifi card. This can be recorded
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[http://nocat.net/download/wpm wpm] (the wireless power meter) or use linux wireless-tools and gpstrans directly. [http://nocat.net/download/wpm wpm] (the wireless power meter) or use linux
wireless-tools and gpstrans directly.
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One way to do this is outlined at the [http://www.ittc.ku.edu/wlan/procedure.shtml "Wireless
Network
Visualization Project"]. In order to compute the Inverse Distance Weighted
One way to do this is outlined at University of Kansas ITTC Wireless
Network
[http://www.ittc.ku.edu/wlan/procedure.shtml "Visualization"] Project.
In order to compute the Inverse Distance Weighted
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[http://www.netlib.org/toms/790 Netlib]. The beginning of the file contains a lot of test code [http://www.netlib.org/toms/790 Netlib]. The beginning of the file contains a
lot of test code

Currently the maps.personaltelco.net data displays a pin point for each AP location. What would it take to display an empirical graph of the power output in order to see what area a particular node covers?

The raw data required comes from a gps receiver and correlated with power

  • output readings from a wifi card. This can be recorded

by NetStumbler, dstumbler or kismet. Another approach would be to hack [http://nocat.net/download/wpm wpm] (the wireless power meter) or use linux wireless-tools and gpstrans directly.

<Insert some sample data here>

The data set consists of measurements of at least a signal to noise ratio (or some other measure of AP power output) for each gps coordinate.

The next step is to use this data to produce a rough approximation of AP coverage. One way to do this is outlined at University of Kansas ITTC Wireless Network [http://www.ittc.ku.edu/wlan/procedure.shtml "Visualization"] Project.

  • In order to compute the Inverse Distance Weighted

interpolation I plan to use a modified Shepard's Method routine from [http://www.netlib.org/toms/790 Netlib]. The beginning of the file contains a lot of test code so search for PRECISION FUNCTION CS2VAL for relevant comments.

--AaronJohnson


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PowerMeterGraph (last edited 2007-11-23 18:00:44 by localhost)