Once again each pair of the six test motes were placed 2m apart. They each ran the BlinkToRadio program and communicated with one another every 1/4 second and broadcast a report packet to the listener on the PC after each communication. The report packet contains the sender ID, receiver ID and the power with which the signal was heard. They ran in this mode for 30 seconds. After each 30s trial, the number of successful communications, averaqe signal strength and standard deviation was recorded.
In two cases the motes performed badly, but after some diagnostic work, the boys discovered that the batteries were not making a reliable connection to the battery holder. Thereafter the batteries were taped into the holder to ensure proper connection.
All pairs of motes communicated between 121 and 124 time each way in the 30s interval with a strength between 51.2 and 59.1. Standard deviations for each communication ranged between 0.7 and 1.6. Raw data are below.
And This graph compares the small differences between the motes.
[...] motes at 1.5m, power 20. Conclusion – Orientation matters.Pairwise compatibility (redo) (best)- facing, 2m, power 20. Comparison of signal strength of seven different motes. [...]
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