Some random scatter data above the baseline was actually due to co-channel interference. Error rate dropped rapidly with increasing strength until at around 20dB SNR the error rate was almost zero. 15dB SNR was necessary to initiate a connection, this corresponds pretty well with the last table assuming a low noise floor. This mode was used to best illustrate loss, because “b” mode uses no forward error correction and hence packet loss is not masked by the firmware. Next is a chart showing typical packet loss at various signal-to-noise ratios, on a 2Mbps “b” link. There is another table commonly circulated on the internet which is even more optimistic, showing a threshold of -92/94 dBm at 1Mbps and -71/72 at 54Mbps, but I don't believe those figures can be achieved in practice, and certainly not with the poor sensitivity of the receivers used in SOHO routers:
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