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Deployment: Tools: /tmp/rssi.log query

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nc8q's picture
Deployment: Tools: /tmp/rssi.log query

Attenuated Suspect <mac> [dBm dBm]: What is an 'attenuated suspect'?

How might this information be of diagnostic value?

Does no entries in /tmp/rssi.log for over 4 days on a very active node indicate anything?

At your leisure.


AE6XE's picture
Chuck,  there is a signal
Chuck,  there is a signal strength monitoring script for the purpose of working around a defect in the wireless driver.   It's a hack until someone can find a root cause fix in the driver..  In noisy environments the wireless logic will adjust many parameters about how the SDR receives the signal to compensate and deal with noise.   It can do such a good job of filtering out the noise that it also become deaf to the neighbor mesh nodes.  The links to neighbor nodes  can drop out.  The defect is the node ends up filtering everything out and never re-calibrates trying to dynamically adjust.  It just stays deaf thinking all is OK.   

Fundamentally, the noise has to be dealt with in another way if it gets to this point, it won't have good thoughput.  If there are no log entries, you have a stable low noise environment.   The logic of this script keeps statistics on the receive signal level in rssi.dat.  It samples each neighbor every min and keeps the average strength for the last hour.  It also tracks the standard deviation in that time period.   When the radio is in a noisy environment it can change some parameters and the received signal strength of a neighbor can jump up/down by upwards of +/-10 dB.   this logic detects if the received signal strength has jumped +/- by (trying to recall) 2 standard deviations, then  it does a slight of hand command on the node to scan an adjacent channel and back.  This forces the receiver to recalibrate and continue to dynamical track and tune for noise.  

The log file shows the before and after signal strength of forcing the re-calibration.   The [ value, value ] is the H & V signal strengths.  The more entries in this log, the more noise or interference in the environment.


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