1.4.4 firmware and Tx issues


#1

Took a pair of B5 lites from 1.4.1 to 1.4.4 today. Link is just under 1km and is using a 40 Mhz DFS channel. Prior to the firmware upgrade, signal was -57 and I had solid 9 MCS on both streams in Tx and Rx.

After the 1.4.4 upgrade, I have a -64 signal and my Tx MCS is moving from 9 to 5 and everything in between constantly. I have tried a couple channels and no change. Noise is -91 and SNR is 25. Both channels I have tried are totally clean.

Anyone else seeing any MCS fluctuations in 1.4.4?


#2

I have a pair of B5’s and noticed that my RX signal dropped about 1.5-2dB after the upgrade to 1.4.4…
My link is 2.5Km and my RX signal is about -50 to -52dBm on 2 X 40Mhz with a SNR of about 30dB, so I am still at steady MCS 9 and no performance impact.
But my RX power DID go down as well as my SNR.

I assume that you can go back to 1.4.1 if you have the firmware file.


#3

Hi chadwick,
For us the 1.4.4 firmware version is stable.
We use a pair of B5C radios in a Backhaul link and remains very stable.


#4

There was a change to B5-Lite in 1.4.4 where the LNA gain table was adjusted by only 1 dB. There are two sets of calibration values, one for long links, and one for short links where the LNAs are bypassed. It sounds like Chadwick’s link may fall into the bypassed case based on distance, but the reported difference is 7 dB which means there is something else happening (e.g. TPC attempting adjustments to improve EVM, dynamic IQ calibration changes, or something else).

There were no changes to B5, B5c or B11 gain tables.

We definitely do not recommend reverting to 1.4.1 because of a potential for memory corruption after a failed upgrade (depending on the previous upgrade path).


#5

anything we need to be concerned about moving from 1.2.0 directly to 1.4.4, and wondering if it’s possible to do one side of the link at a time as the remote side is currently offline and will be about an hour before our nearest tech reaches the site. Like to take advantage of the down time and upgrade the side that is up provided it won’t cause any problems trying to connect again etc.


#6

Hi Chad, have you been able to fix your usse? what was wrong? BTW how much real throughput you are passing on that link?


#7

Issue has stayed the same. We were on a 40 Mhz link and only able to pass about 175 Mbps. We took it up to 80 Mhz (since it is short and protected) and we are getting around 275 Mbps now.


#8

mmm that is a shame I was planning to buy 2 b5lite for a 2 mile link but I have not seen positive comments about mimosa. I just need to pass 100/100 mbps. Also, are the b5 lite stable, no link drops, latency? tks


#9

Well, let me back up… A minor issue with a firmware update that might be unrelated to that update is not me complaining about the product. I have a number of these in operation and I don’t hesitate to purchase additional backhaul products from Mimosa. I’ve had much better luck with backhaul radios from Mimosa than I have with other companies.

For a 2 mile link, you definitely want to use the B5, not the Lite version. You’ll have no problem with 100 Mbps symmetrical on a B5 at that distance with a 2x20 or 1x40 link.


#10

tks for the feedback I guess I will try those mimosa then


#11

We have several Mimosa links at around 5 miles. Very happy with the performance.