This was a test using the spider antenna tilted downward at a 45 degree angle. This was only true when the antenna was facing the motes head on. As we rotated the antenna, the plane through which the 45 degree cut changed and you can really see how this affected RSSI values at the farther distances of the boxplot below:
Here is boxplot of just the top motes to help get rid of the noise produced by the two different heights:
Also, here is a Cumulative Data Function Plot
On the top motes it looks like we could discern between .25 and .5 or we could go between 1 and .75 meters. Again there is little distinction between .75 and .5 meters (the range we want).
The following is a plot of the bottom motes CDF
On the bottom motes however, there appears to be little distinction across the whole range of pertinent distances.
[...] Spider Antenna, 45 Degrees. We did this test to see if we could angle the “sweet spot” of the antenna through the center of the target area. We did 2 heights, 4 distances and 10 angles. Conclusion: Significant angular dependence (not surprising). If you look only at the regions near the front of the transmitter, there is good separation between the .25, .5-.75, and 1 m ranges, but the middle two ranges were not well distinguished. [...]
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