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100% LQ 100% NLQ TxMbps 0

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K3GX
100% LQ 100% NLQ TxMbps 0

We are using NanoStation M2 units here, Ch -2, 10 MHz BW. When two nodes are a mile apart with a fair amount of obstacles, I'm achieving 100% LQ, 100% NLQ and around 20-30 TxMbps which seems reasonable.  However, when I take another NSM2 to a mountain top with line of sight and 7 miles apart, same settings, I'm getting 100% LQ, 100% NLQ, but 0.0 TxMbps. I'm able to connect fine, but the link is quite a bit slower than the one mile link. It's still a single hop because I cannot see any other neighbors from the mountain top. Why would all the packets be successfully received both directions, but the throughput reduced? I verified there wasn't anything going on with the nodes by moving them closer (in the same block) and was able to get around 35 Mbps if memory serves.

Also, we noticed on the one mile link that it didn't make any difference on signal strength, but we doubled our throughput by going from 5 MHz to 10 MHz BW. That makes sense, but I'm wondering if the 10 MHz BW is not favorable for the 7 mile link and we need to go back to 5 MHz.

Thanks,
Dave K3GX
 

KG6JEI
The speed parameter only

The speed parameter only shows a data rate when there is directed traffic (this excludes the beacon packets that create the LQ/NLQ statistics) otherwise it only shows 0.0

I suspect most likely you did not  have any real directed traffic flowing at the time across that particular link (eg you need to watch a camera or stream a large file, etc from something located on the path of the node you want to see speed for)

nc8q
nc8q's picture
but the throughput reduced?

See:
https://www.ubnt.com/downloads/datasheets/nanostationm/nsm_ds_web.pdf
Note that the datarate (Modulation Coding Scheme) is reduced as the signal strength is reduced.
Here is an URL that demystifies MCS.
https://www.controleng.com/single-article/understanding-modulation-and-coding-schemes/88a93ea898e26741cb6e284cd64a4bf0.html

Elsewhere in this forum it is mentioned that the LQ and NLQ values are determined by broadcasts at the minimum datarate,
1 Mbps at 20 MHz bandwidth. In your example, 0.5 Mbps at 10 MHz bandwidth.
In your example, to display a current valid TxMbps, you may connect to the other node's
'Mesh Status' screen and click the 'Auto' button. This will cause some data to be transferred
and should result in TxMbps value above 0.0.

Hope this helps,
Chuck

 

KE2N
KE2N's picture
Rate

Putting iperf on your nodes is probably the best way to assess the throughout.

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