[net2-wg] link estimator interface

[Philip Levis]

On Mon, 2006-03-06 at 10:19 -0800, Joe Polastre wrote:
> Its ratiometric.  Ie, if node A has a value of 20, then any node (say
> node B) with a value < (20 - (20 >> 2)) = < 15 is at least 25% better
> (less transmissions required).  That's relative, node B is estimated
> to require 25% less transmissions than node A.

Some data a student here has been collecting suggests that LQI doesn't
behave like this at all. I've attached a plot of LQI vs PRR.

This plot is from a short packet burst (200 packets at 100pps), so the
outliers don't denote long-term environmental variations. Also note the
variance on LQI readings, which suggests that a single LQI reading is
not a good thing to base decisions on.

Phil
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