PTP 450 re-ranging 5 times a day

Hi,

We have a 6.9 mile link using reflector dishes.

Here are some config stats:

5.7GHz MIMO OFDM - Backhaul - Timing Master - 0a-00-3e-b3-da-9e
Board Type :
P11 C120
Software Version :
CANOPY 13.4 BHUL450-DES
Board MSN :
6069RU086V
FPGA Version :
040715
Uptime :
23:35:22
System Time :
13:20:59 02/16/2016 MST
Ethernet Interface :
100Base-TX Full Duplex
Regional Code :
United States
Regulatory :
Passed
Antenna Type :
Integrated
Channel Frequency :
5740.0 MHz
Channel Bandwidth :
20.0 MHz
Cyclic Prefix :
1/16
Frame Period :
2.5 ms
Color Code :
****
Transmit Power :
17 dBm
Temperature :
40 °C / 104 °F

we are seeing this link re-range up to 5 times a day. I turned down the power by 4 db a few days ago thinking it might be too hot, but that just seemed to reduce us from 8/8 to 8/6.

MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/16/2016 : 13:21:19 MST : Status : 3 Flag : 1728840
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/16/2016 : 08:37:39 MST : Status : 3 Flag : 1728840
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/16/2016 : 06:02:58 MST : Status : 3 Flag : 1728790
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/15/2016 : 20:25:24 MST : Status : 3 Flag : 1728790
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/15/2016 : 15:35:24 MST : Status : 3 Flag : 1728790
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/15/2016 : 13:46:36 MST : Status : 3 Flag : 1728790
 
 What causes this issue and how can we mitigate it? the outages last upwards of 1 minute each.
 
Thanks
 
Sam

@sam wrote:
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/16/2016 : 13:21:19 MST : Status : 3 Flag : 1728840
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/16/2016 : 08:37:39 MST : Status : 3 Flag : 1728840
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/16/2016 : 06:02:58 MST : Status : 3 Flag : 1728790
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/15/2016 : 20:25:24 MST : Status : 3 Flag : 1728790
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/15/2016 : 15:35:24 MST : Status : 3 Flag : 1728790
MAC : 0a-00-3e-b3-d7-3e BH ReRange 02/15/2016 : 13:46:36 MST : Status : 3 Flag : 1728790
 
 

Sam,

The BH ReRange is the normal process for the BH registration process. The BHM starts with an initial small frame and waits until the BHS first attempts to register. Then the BHM detects the distance of the BHS, and fails its registration telling the BHS to ReRange. The BHM configures a new frame with the exact distance of the BHS so that no airtime is wasted. 

All that to say is that ReRange is not the cause of your problem, but just a symptom of your link going down and coming back up. The question is why is it losing its link the first place. Is the BHS resetting? VC error? We will need more information to try and figure out why it is dropping. 

You do not have to turn the Tx power down on Backhauls, so that can be turned back up to get your 8X back.

Would you be willing to try the latest release for PTP 450 14.1.1 or even the 14.1.2 beta? That would be helpful to see if you are still seeing the problem.

Enjoy your day,
Charlie

Hi, the radios are not powering off randomly, the event logs only show time set  and a lot of them. SNR is above 33.

What can I send your way for evaluation? Should I open a ticket?

Sam


@sam wrote:

Hi, the radios are not powering off randomly, the event logs only show time set  and a lot of them. SNR is above 33.

What can I send your way for evaluation? Should I open a ticket?

Sam


Sam,

Would you be willing to try the latest release for PTP 450 14.1.1 or even the 14.1.2 beta? That would be helpful to see if you are still seeing the problem.

Enjoy your day,
Charlie

I had the same problem on all my PTP450 links, with firmware 14.1.1 the disconnections are less frequent.

2 Likes

Sam,

I'm having a very similar problem with a 5.4 GHz PTP450 link, running 13.2.1.2 BHU450-DES

It may run a few days without a glitch, then drop multiple times in an hour.  RF stats look decent, so hoping to narrow down the source of the problem.

Curious if you tried going to 14.1.1 or the 14.1.2 beta.  If you did, was there any improvement?

TH


@TDH_95490 wrote:

Sam,

I'm having a very similar problem with a 5.4 GHz PTP450 link, running 13.2.1.2 BHU450-DES

It may run a few days without a glitch, then drop multiple times in an hour.  RF stats look decent, so hoping to narrow down the source of the problem.

Curious if you tried going to 14.1.1 or the 14.1.2 beta.  If you did, was there any improvement?

TH


We solved the problem this way:

1) Select only the master frequency on the slave, if it disconnect from the master it will take less time to reconnect

2) If you have a PMP450 AP on the sector, you can use the RJ-12 port to bring the sync to the PTP450 Master

Using both workaround, we have PTP450 links with session uptime greater than 1 month

Thanks for the suggestions, but I think I've solved the problem.

I discovered that the link was very sensitive to alignment, and although the RF stats in the alignment tool didn't seem to show it.  After adjusting the BHM alignment one evening, Ihad 83 re-range occur overnight.. After returning to the original alignment, I was back to just periodic drops.  I then trimmed some vegetation that was fairly close to the BHM, but not directly in the path.  Since then, the link has been up continuously.