OK, now I'm really confused.
I worked out how to get the SNR for each separate tone (all 252 of them) and plotted a graph at a time when the overall SNR margin was 8dB and I was getting lots of dropped packets.
Several hours later the connection recovered and I plotted a new graph of the SNR against tone (or bin).
The two graphs were identical.
What I expected to see was a difference between the graphs that indicated which frequencies (or bins/tones) were getting overwhelmed with interference.
What's going on?
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