I hate to say it, but i have no experience with 5ghz ptp over distance.

I've done 2.4, and 900 with no issues. But I have a .75 mile link (1.2km) link between a 20 story building and a 4 1/2 story building. Its right through the top of a leafy oak tree.

I know there are alot of 2.4 APs around (consumer) so i wanted to use 5ghz, for the improved latency and Bandwithd, and less interfearence (right?)

I wanted to use a rootenna on one end, which will be going through a thin glass window, no lead, then the tree and directly to the other roof top.

I wanted to use R52s if possible.

any input before i get out there and waste time potentially? im not a fool, i know u guys cant give me numbers or anything specific about the link quality, but what i'm looking for is some kind of input on 5ghz through the top of a tree.....for all i know that may be a BIG no-no.

this is not a serious link, only 2-3mbit for like 10 very casual web browsers..and maybe a few low low use voip lines.


Thanks for the help.

Mesh system work in 5.8 ghz, with Nlos (Trees, buildings, etc...) but with more power radios, like 500 mw and better sensitive cards...

I suppose that the R52 is not a good card for your situation....

Regards

good point on mesh.

I really wanted to use r52s, I was hoping the 15 and 19db antennas would ofset low power.. r52 does have good Rx sens btw.... I could use some extra nmp8602s that I have..but those are not very reliable.

so I guess thw question at thispoint is does anyone have any short range 5ghz on cm9 or r52 with slight obstructions experience?

thanks for the quick reply chipi.

The Pacific wireless GD58-22 is a nice high gain grid in a very small package, if you need a few more DB. It's not much larger (if any) than the PA-19.

We did a PTP test for a customer between 2 buildings @ 1.9 miles with SR9 on RB532 w/ 12db plat panels on each end. We had multiple trees and a hill to go through were still able to get a 1 meg link at -85db. This was with the standard b setting not 5 mhz but I would think with 1 tree a 1 kilometer you should be able to get 3 meg no issue. Make sure you use a higher cpu board like the 433AH so you don't have to deal with and CPU load issue.

I used a 24dBi Rootenna and R52's for a p2p shot. Still haven't put it up, but in testing, signal was awesome. -30's from 50ft away, shooting through 2 walls, my fridge, my washer/dryer/water heater/tv/etc.

It would have to be one hell of a tree to really put you down, although from time to time the ping might fluctuate.

I have a few 5GHz links with EMP-8602+S cards and PAC Wireless echo series 17dbi antennas. The links are all 1/4 to 1/2 mile and I could not get a reliable connection until I moved the antennas away from the trees.

Edit: It could depend a lot on the power, type of antennas used and the type of trees, (size of the leaves).

I have quite a bit of experience with 5 gig and as stated above, trees will kill it fast. Tree growth is a real problem too. A new link was installed a couple of months ago with -62dbm signal level and good performance over a 2 mile path. After a 3 week period the signal went down to high 70's then a week later middle 80's and would drop out all the time. Raised antenna a few feet and now -57dbm. Only thing in the way was a few scrub trees.

Very short distances, of under a couple hundred feet you can probably punch thru.

I hope this helps.

The answer is almost always (unless its obvious based on other experience) that you never really know until you try because every environment is different.

I will agree with those above and say that do not ever build a new link knowing you have to go through trees unless it is less than a half mile and its like maybe one tree.

Scott

Try it. Most probably it will work.
You might still get into trouble when raining....... that tree will look like a reinforced concrete wall then....... because of the water.
I have perfectly working links with 1 oak, about 15m circumference, on about 1.5 km, with 12db omni+11 db yagi. No los at all, or maximum 1% on heavy rain. Your conditions may vary.

We have a redundant link - 4 Km (± 2½ miles) in 5.8GHz and we used CM9's with 27dBi grid antennas.

Generally we get -60 out of this link and we cannot actually see the other side through the tops of the trees. This link runs at 54Mbps air-rate all day and has been in operation for > 2 years. We also have it running in Nstreame.

So I guess to answer your question - yes it works, but I would approach it with caution.
Some testing might be the order of the day just to make sure it'll be stable.

Hope this helps.

Tanker