Derek finished an experiment with how the Puck signal is picked up by a vertically oriented mote in the expected position and orientation relative to the puck at power level 5.
The motes were placed at distances of .25, .5, .75 and 1.0 m from the puck at orientations from 0 to 180 degrees in increments of 20 degrees. The motes were placed at either .1 or .35 m below the height of the puck (the relative range of height of someone’s pager when the puck is mounted properly on the wall). At each position the puck broadcast messages and 3 motes ran the ParrotPacket software, recording the signal strength in their flash memory. The data were then saved to a file and imported into MiniTab for statistical analysis.
The results suggest that distance and orientation are significant as is their interactions and their interactions with height. Height itself is not significant.
I ran a general linear model with distance as a covariate, height and distance as fixed variables. The results are below. They indicate that the most important effects are distance, orientation, the distance X orientation interaction and the distance X height interaction, in that order. There are a couple of particularly tricky angles, particularly 40 (esp. low position), 100, 120 and 160 (especially high) degrees.
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