5.8GHZ link performance

RouterOS Wireless Networking
1

We have just installed a new 5.8Ghz PTMP setup but are questioning the performance we are getting. Here are the details:

AP: SR5 400mw with 17dbi Sector Antenna on P4 1.6GHZ
Client: SR5 400mw with 22dbi Grid on RB532

Absolutely perfect clear LOS at about 2 miles…

Signal = -82 and fluctuates between 24-36mbps

Does this seems right?
I would have expected a -50 to -60 signal, as this an absolutely perfect LOS and only 2 miles away.

I know it is not the cards as I received 54mbps perfect links in the lab with them.

I am going to change out the pigtail tomorrow, to eliminate that…

Is there a calculator out there online to determine what a signal should be based on input details?

Any body have any performance data with 5.8GHZ PTMP MT setups, prefereably with the SR5 400mw cards?

SMA

2

INTE... RADIO-NAME MAC-ADDRESS AP SIGNAL... TX-RATE

0 wlan1 00156D100AXX 00:15:6D:10:0A:XX no -66 54Mbps
1 wlan1 00156D100AXX 00:15:6D:10:0A:XX no -69 48Mbps
2 wlan1 00156D100AXX 00:15:6D:10:0A:XX no -66 54Mbps
3 wlan1 00156D1009XX 00:15:6D:10:09:XX no -63 54Mbps
4 wlan1 00156D1009XX 00:15:6D:10:09:XX no -63 54Mbps
5 wlan1 00156D1009XX 00:15:6D:10:09:XX no -65 54Mbps

As you can see here, you have quite low signal. This is report from Mikrotik 2.8.26 machine acting as AP, using 12dBi omni antenna. Six clients are 2-3km away and they all have quite stable signal running at full speed. One of the clients doesn't have perfect LOS, there is small obstable on its way. All machines are running 2.8.26 on 500MHz P3 machines with SR5. All six clients are using 22dBi grid antennas from Pacific Wireless.

What kind of cables are you using? What about pigtails from U.FL connectors to N-female? They can make problems.

3

<< What kind of cables are you using? What about pigtails from U.FL connectors to N-female? They can make problems. >>

We are using premade PCI card from Demarctech, which are the SR5 with a U.FL to SMA adapter built in. From there a LMR195 SMA to N pigtail takes us to the LMR400 run up to the antenna about 30-40 feet away only…

We’ll be trying new pigtails tomorrow, and using the MMCX SR5 port instead as well…

Now that I see you with similar distance and only an omni, and getting -6X signal, I can assume something is indeed wrong I guess…

SMA

4

We had problems with antenna ground at some places. If we put antenna on the metal pole, we had about 6dB lower signal. Then we just insulated part of the metal pole and put antenna over the insulation. Still, you probably have some other disturbances because your signal is something like 20dB lower.

5

I’m using the same cards and PW 22dBi grid antennas gear over a 5km (3.1 mile) link and getting a consistent -55db signal at each end.

LOS is good but not perfect. I have kept the antenna cables (LMR400) down to just over a metre each but I would prefer to use better quality N connectors than I already have. In order to achieve the short runs I have RB532s mounted in weatherproof boxes.

I think your longer cable runs will be contributing to the outcome but might not be the only cause. Make sure the polarisation is the same for both antennas; try and rotate one of them by 90 degrees and see what happens.

6

Do a physical inspection of the connector on the card too. While the pigtail may be just fine, the actual connector could be broken.