Airplane777
join:2004-06-20
edit:
July 4th, @01:07AM
| reply to AMD Phreak
Re: Interference on your CPEs or APs ?
Hi all:
thanks for your comments on 2.4.
I can definitely see that 2.4 G would have less interference in rural areas, but I thought there were WISP operators here that used 2.4 G in areas that still might have a lot of homes and businesses.
I can see though that 5 G probably would have less chance of interference into the CPE in crowded areas.
Right now I'm not getting interference on my AP...yet...lol. Seems that people are staying away from my channel around my AP.
I'm wondering though, is it rare to have interference into CPEs on 2.4 G? I'm hoping to hear from others (who use 2.4 G in crowded areas) on this also.
I might just be having some bad luck having an interferer so nearby.
I do see though that I need to use an antenna with sharper forward gain, and much less gain to the side (where the interferer is).
I was thinking of putting my AP up on a mountain. Even so, I still could have my CPEs mounted in business areas and neighborhoods, where other people are operating APs on channels that I'm using. It seems that I could run into a lot of interference that way. Maybe interference into your CPEs happens to you all who use 2.4 G in business areas and residential areas?
Gee...I would think you all would have interference into your APs, if your APs are up high on a tower or a mountain.
Now I'm starting to have second thoughts about using 2.4 G...lol.
Thanks |
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robbin
Premium,MVM
join:2000-09-21
Leander, TX
| said by Airplane777  :Now I'm starting to have second thoughts about using 2.4 G Good -- you need to use something which is proprietary and has polling. Whatever the frequency -- that doesn't really matter. I like Trango, others like Canopy, there may even be some new ones out I haven't heard much about. If you want to eliminate problems, go with one of them. |
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Diddy1
join:2003-07-19
Sidney, NE
| I'm looking at 2.4Ghz more and more as a "start-up rapid deployment" space now days. Get up and running fast and get a subscriber base going for cash-flow. Now I've started considering the benefits other technologies offer in the 2.5Ghz band as well, like robbin has mentioned. I will however add a second note about elevation. Not only is it best to have your APs high and generally out of the plane of standard SOHO gear, but I try to have CPE up as high as possible as well, unless I get an incredible RSSI level at a lower heigth. My problem is not interferrence at the APs, but at the client locations since they are down "in the grit of it". But, I am no "engineer" either 
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if you fail to plan, you plan to fail |
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cmaenginsb
Premium,MVM
join:2001-03-19
Palmdale, CA
| reply to Airplane777
said by Airplane777 :Hi all: thanks for your comments on 2.4. I can definitely see that 2.4 G would have less interference in rural areas, but I thought there were WISP operators here that used 2.4 G in areas that still might have a lot of homes and businesses. I can see though that 5 G probably would have less chance of interference into the CPE in crowded areas. Right now I'm not getting interference on my AP...yet...lol. Seems that people are staying away from my channel around my AP. I'm wondering though, is it rare to have interference into CPEs on 2.4 G? I'm hoping to hear from others (who use 2.4 G in crowded areas) on this also. I might just be having some bad luck having an interferer so nearby. I do see though that I need to use an antenna with sharper forward gain, and much less gain to the side (where the interferer is). I was thinking of putting my AP up on a mountain. Even so, I still could have my CPEs mounted in business areas and neighborhoods, where other people are operating APs on channels that I'm using. It seems that I could run into a lot of interference that way. Maybe interference into your CPEs happens to you all who use 2.4 G in business areas and residential areas? Gee...I would think you all would have interference into your APs, if your APs are up high on a tower or a mountain. Now I'm starting to have second thoughts about using 2.4 G...lol. Thanks Ya know you asked the same questions a while ago. Since the hilltop sites are located away from town, no you don't get much interference from them. You do get interference on the CPE, that is solved by high gain antennas and limiting distance.
In the city we use a minimum of a 19 db antenna for CPE and 12 for sectors. We can plan on going 5 miles and not seeing the effects of interference. In rural areas of course we can go further because chances of interference are less, we however can also use higher gain antennas like grids to overcome this.
I ran a WISP in Los Angeles and found primarily interference came from other WISPs in many cases located on the same hilltops. |
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superdog
I Need A Drink
Premium,MVM
join:2001-07-13
Lebanon, PA
 ·WaveCrazy.Net
| Bob, I run 2.4Ghz a an area that is full of AP's. An example from a site survey:
wavecrazysunset 00:18:d2:00:3c:4d 1 (B+G) AP no 67
wavecrazysunsetnorth 00:18:d2:00:3c:45 10 (G) AP no 60
07B403257444 00:12:0e:70:33:46 6 (B+G) AP no 50
linksys 00:0c:41:c0:3c:9b 6 (B) AP no 44
wavecrazysouth 00:18:d2:00:56:54 9 (B+G) AP no 38
NETGEAR 00:1e:2a:4f:92:72 1 (B+G) AP no 36
MOT-1-29 00:18:c0:61:0d:29 11 (B+G) AP no 35
linksys 00:18:39:d1:48:56 6 (B+G) AP no 29
Jumpstart-P1-799a23 00:11:95:55:53:29 6 (B+G) AP no 24
101 00:03:47:14:a6:3d 11 (B) AP no 23
keener 00:14:bf:c0:c1:d2 11 (B+G) AP yes 21
Stone Barn 02:d0:d8:60:08:91 11 (B) Ad hoc yes 20
trauma 00:18:4d:9a:dc:f0 6 (B+G) AP yes 20
wavecrazyELCO 00:19:3b:10:1f:ee 1 (B+G) AP no 18
EdKHershey 00:13:10:2d:1c:38 6 (B+G) AP yes 15
Ceresini III 00:e0:98:fd:d8:e8 6 (B+G) AP yes 15
06B403539321 00:12:0e:3c:ab:07 6 (B+G) AP yes 13
NETGEAR2 00:14:6c:9e:4a:a6 11 (B+G) AP no 13
EBERHART 00:11:95:39:5e:65 6 (B+G) AP yes 10
My AP's are on horizontal polarity. You can see that quite a few of my other AP's can see each other. I have yet to run into a situation where my AP is not stronger than a small Linksys AP that a neighbor is using etc.
You need to use a higher gain antenna on every CPE. This will fix your problem.
--
»www.wavecrazy.net
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Airplane777
join:2004-06-20
| reply to Diddy1
My CPE with the interference is up on the second floor of a condo. I found out the interferring AP is right across the street in a rehab hospital, with a great shot right to my CPE.
I do see what you are saying about getting the CPE out of the plane of standard SOHO gear. |
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Inssomniak
join:2005-04-06
Cayuga, ON
| reply to superdog
I was in competition with one WISP in an area, they ran vertical pol, and I ran horizontal, but they pulled out of the area after DSL came into town, and they switched everyone to DSL, but all my customers wanted to stay wireless mostly for cost reasons, after all their customers were out, they cranked the power of their AP and some users that were close to it had too much interference even with the narrowest beam antenna I had. I managed to flop channels around to fix it. |
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Airplane777
join:2004-06-20
| reply to robbin
said by robbin : Whatever the frequency -- that doesn't really matter. I know Canopy can handle interference even if it is just 3 dB below the Canopy signal. However it would seem that even propritary systems can have problems, if interference is on the same frequency...and strong enough. |
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Airplane777
join:2004-06-20
edit:
July 4th, @12:03PM
| reply to superdog
Thanks for the info Tim:
I will switch to a higher gain antenna to help lower this interference, which is coming in from the side. Right now I'm just using the antenna thats built into my 2300, which I guess isn't all that narrow beam. i can't find any antenna patterns on the manufacturer's web site, for the built-in antenna on my 2300.
I was out last night with my Netstumbler, and I could see if I switched to horizontal polarity, this interferer's signal level dropped down.
So I can see when I put an AP on the mountain, I definitely will use horizontal polarity. I might even switch to horizontal polarity here at home, if I can find a horizontal omni with downtilt...and it's not too heavy for my tv mast (I don't want my tv mast swaying in the wind due to a heavy antenna). A good 2.4 G horizontal omni with downtilt might be hard to find. |
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AMD Phreak
Please do the needfull
Premium
join:2003-12-14
| You can have problems with 2.4GHz canopy as well. It just happens that the MAC is built from the ground up to deal with high noise environments. This allows it to tolerate if you will, more noise. Noise is noise however, and there comes a point where the receiver on the CPE or on the AP gets completely swamped and can no longer function. |
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Airplane777
join:2004-06-20
edit:
July 6th, @03:38PM
| I was up on the mountain yesterday afternoon to check for interference in the 2.4 G band (to see which of the 2.4 G channels I can use).
Looks like I can only use ch 11. I see two other transmitters around ch 1 & 6 are already being used by someone else. I think they are propritary radios, since they don't show up at all on my Netstumbler. I found them using my RangeLAN spectrum analyzer.
I wish there was an inexpensive spectrum analyzer for the 5 G bands, similiar to the relatively inexpensive RangeLAN2 and Wi-Spy devices which are used on 2.4 G for spectrum analysis. I will need a 5 G PTP shot (to the mountain), and I will have no idea which channels are clear (without a 5 G spectruum analyzer). I guess I could try different channels and do pings on each channel, and pick the one with the fastest ping time. That might be a crude way to tell if a 5 G channel is clear. |
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robbin
Premium,MVM
join:2000-09-21
Leander, TX
edit:
July 6th, @03:31PM
| Buy a used radio off of Ebay. Trango has a spectrum analyzer feature built-in. I think Canopy does as well. Then when you are finished, sell it. You won't be out much more than shipping.
[edit] A used 5830 series Trango will cover both the 5.2 and 5.8 GHz bands. Or just buy a used Link-10 pair and install and use them. There is a set on Ebay right now for $750 buy it now - may go cheaper with bidding. |
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Airplane777
join:2004-06-20
edit:
July 6th, @03:43PM
| Hi robbin:
Thanks for the info. Another fellow mentioned about Canopy SM modules yesterday. Thats nice to see that Trango has a spectrum analyzer feature also.
Aren't there 4 different 5 G bands? I guess I would need to figure which of the four 5 G bands is best for WISPs, then buy that Canopy or Trango radio off ebay.
Or maybe the spectrum analyzer feature in a Trango will cover all the 5 G bands?
I see Canopy sells 4 different 5 G band radios (5.2, 5.4, 5.7 and 5.8 G). Which band do you all think is best for WISPs? I have a vague recollection that one of these bands requires low power operation, and thus might not give as much coverage?
[edit] Is 5.4 & 5.7 not used that much? |
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Airplane777
join:2004-06-20 | reply to robbin
Whats a Link-10 pair. Never heard of that. Is that by Trango? |
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robbin
Premium,MVM
join:2000-09-21
Leander, TX
| reply to Airplane777
It depends on your link -- how long is it? 5.2 is lower power than 5.8 but if you only need to go a couple of miles it would be better as there is less interference in that band. 5.4 is new and has unusual requirements regarding power, radar installations, etc. Personally I would stay away from that band unless the others were to crowded to use. 5.8 is best for distance. I don't know why Canopy sells a 5.7 also unless it is for overseas use -- Trango's units cover that upper band in one unit
Link-10 is Trango's first PtP backhaul radio pair. They operate on both 5.3 (what we are calling 5.2) and 5.8 GHz. The pair currently for sale is for external antennas. Unless you need to go a long ways I would look for a pair with integrated. They don't do as many packets per sec as some of the new radios but it would probably be a good choice for your first link. They do 10Mbps dynamically so if you need 9 down/ 1 up one second and 5/5 the next, that is what they deliver. They are rock solid if your area doesn't have a tremendous amount of interference and come with all of the normal Trango goodies. |
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Airplane777
join:2004-06-20
edit:
July 6th, @03:59PM
| Great info Robbin. Thanks much.
That will help me out.
Since I only have one 2.4 G channel that I can use (ch 11) up on the mountain, if I need more AP point channels, I might have to go with 5 G.
Whats the max client radios that can operate into one Trango AP on 5 G? I think some 2.4 G radios say 25 or 30 is the max # of clients. Maybe more, since the BW is higher on 5 G? |
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robbin
Premium,MVM
join:2000-09-21
Leander, TX
edit:
July 7th, @03:20AM
| I've heard of people with over 100 (even up to 150). |
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LLigetfa
join:2006-05-15
Fort Frances, ON
| reply to Airplane777
said by Airplane777 :I think some 2.4 G radios say 25 or 30 is the max # of clients. Bob, you cannot tar all 2.4 radios with that brush. That limitation is for 802.11 and there are lots of other products out there in 2.4 running polling MAC that supports more subs per AP.
--
Strange as it seems, no amount of learning can cure stupidity, and formal education positively fortifies it. -- Stephen Vizinczey |
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robbin
Premium,MVM
join:2000-09-21
Leander, TX
| Agreed -- When I talk proprietary it is the same as saying polling MAC. However, if the terrain allows to get away from 2.4 it would probably be wise. The noise floor is almost always going to be worse on 2.4 than it is in the 5 GHz band. Of course, there will be more problems with trees in the upper band. |
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