Forum

Weather, or not?

30 posts by 4 authors in: Forums > CWNA - Enterprise Wi-Fi Admin
Last Post: July 5, 2009:
  • Hi Guys

    I have a Moto Backhaul system installed in the UK as 2 seperate chains with 3-4 hops. they have been up and running for a couple of weeks, however there has been some serious downfalls and hailstone in the last couple of days. I haven't been able to get to site yet to look at the report logs, however the client experienced around 5 drop outs for around 10-30 minutes on the last two hops in one chain. The weather is now fine and so are the links!

    The links in question have an efficiency rate of around 98% with around 30% bandwidth headroom. The distances are no greater than 100M and they are mounted on CCTV columns at 7M.

    Any ideas on if or why these links should be affected by bad weather? My understanding has always been that they are immune to weather.

    CP

  • I grew up in Manchester, I remember there were three kinds of weather -

    a) Gonna rain
    b) Raining
    c) Just been raining...

    To answer your question though, bad weather does indeed affect things.

    Neil Mac
    CWNT

  • LOL...

    Still the same, although the site is slightly north of Manchester, btbh the weather is worse.

    In your opition though, should it affect it to the extent of knocking it off line for a period?

    They have some existing installations in the same are with Alvarion I think, but report no drop outs with them!!!

    EDIT: "Option 2, it is now raining. Had option 1, just waiting for option 3 now, or maybe not!!!"

    CP

  • What frequency are you at? That makes all the difference. If at 5GHz or below, the rain won't do anything noteworthy. I have 20 mile backhaul links at 5 GHz that don't even sneeze when it rains cats and dogs.

    GT

  • Hi GT

    They are running in the 5GHz range!

    CP

  • What is the signal at each end?

    Hard rain, even over a long distance, will fade a 5 GHz shot < than 3dB. Like I said, we have 20 mile shots at 5 GHz and don't have dropped connections due to the weather.

    What is more likely is that when it rains, some PoE or RF connector is getting wet. Now that I have seen a bit more often. :)

    GT

  • Hi GT

    I have taken some screen shots from last time I was there. I will check to see if I have signal values.

    The water idea is good, so I will check it out. However would they come back up after drying out or would we still see intermittant issues?

    CP

  • Have put a few notes on rain for CWNA folks etc in a separate posting.

    Dave

  • Hi Dave/GT

    Just had another update and the cameras were fine last night, however they went off at 9am for 30mins, but the weather wasn't too bad, only spitting.

    I am guessing that the idea of water penetration holds a little more water (pardon the pun...). Will have to go to site over the week I think and do a full audit of the system as it still could be the cameras that is the issue and not the wireless!

    CP

  • Hi CP

    One thing we can say for certain now is that it is not rain on the link itself that is causing it, as the rain was only spitting or light.

    Dave

Page 1 of 3