Happiness in the woods

Hello All,

Question for those with experience in mountain deployments. We just completed a 12 mile backhaul deep in to the Mountains of New Mexico. We are at 10000ft at our first leg (-58, jitter 2). We are about to go another 15 miles to our destination.

The intention here is to reach a resort area with about 250 residents. Trouble is, most all homes are surrounded by ponderosa pines.

So, my question is this, what freq would you all use in this environment? My search for an answer has produced several conflicting opinions. There is almost no radios at all, save for a fire station, that uses wireless here.

I have been thinking about setting up a mesh network to cover the 30 square miles these folks live in to help with coverage… still gathering info at this point


900MHz is your best bet.

I was thinking this as well, but someone informed me: "You don’t want to mess with 900MHz because of the interference with the GSM telephone networks."

Any validity to that?

I am running four 900MHz AP’s with customers between 2.5 miles and 20 miles. My home link is a 900 at 6.5 miles through a stand of trees.

We are in the SF Bay Area (call it Cellular Hell) which is one of the noisiest RF environments anywhere and it works very well. From time to time we get interference, 99% of the time I can deal with it. This is true of any RF based system. In your case it sounds pretty rural so your chances of interference are minimal.

With anything higher than 900 you are going to run into line of sight issues. 2.4 will tolerate light foliage, 5.7 virtually none. You could consider rolling out a 2.4 and a 900. Use 2.4 when LOS is fairly good and 900 as the backup.

Well, here is one you have to see to believe. We are running an 900 AP cluster off of a TV tower on top of a 3200ft mountain. Our equipment is located at 1432ft off of this 1600ft badboy so you can just imagine what kind of links we are getting here in the deep woods of western NC. So far we have gotten Nlos links at 8 plus miles and LOS links at 20 plus miles with signal strengths at -72 to -49dbm with jitters only an installer could love. God I love canopy!


use a couple of backhaul nodes off of your destination (link endpoint), if you really want to pimp it out, but yeah; 900.

in my experience, the high (923) frequncy rocks to about 2 miles, while the lower end (906ish) works best for distance. You have to be more patient with the 900 than with other frequencies, in terms of the time it takes a unit to register up, but once it joins the party … .frikken solid.

One note of caution… Pine trees pose a significant problem to even NLOS 900mhz. While we have NLOS installations with 900mhz going through 6 miles of solid deciduous (mostly red maple) trees I also have potential customers at 2mi where I can’t connect at all because it would have to go through one layer of pine trees. For some reason the physics of the needles must wreak havoc on the propogation of the signal. Make sure you do lots of link tests before you purchase the equipment and find you can’t reach many subscribers…

Has anyone else run into this problem wth pines? Any idea why?

YES, pine tree’s are my worst night mare

kur356 wrote:
Has anyone else run into this problem wth pines? Any idea why?

I heard once that the pine needles act as little antennas and absorb RF energy. But I'm not sure it was a reliable source, and that may be more somebody's speculation than anything else. Consider it a rumor -- or me gullible...

If true, I'd also expect the type of pine and needle length to have bearing on the signal loss. But I'm new at this myself, so I don't know if that is the case or not.


Weird thing about those pesky pine needles…

Varying length, but many near the 800/900 MHz antenna length is what “I” have heard - one of our instructors swears that he avoids pine-needles whenever he can due to the RF challenges…

If the tree is “too” much of a problem you can always celebrate Christmas early… :wink:

It’s the density of the tree.

Evergreens hold alot of water (sap is mostly water). Combine that with the density of the needles and it looks like a wall to RF at pretty much any frequency. When it rains, the needles hold more water than most other broad leaf trees so it gets even worse.

Hello All.

A quick update. After the successful backhaul we repeated on a 400mw Mikrotik setup (1- 18db 180 deg antenna to cover the potential service area near the repeater). Somehow we are reaching a client 1 mile through the forest. I am really surprised, as we have zero visibility to the tower, and it’s just layer after layer of Ponderosa pines. Our speed and ping tests were outstanding, so we think we will go after the resort now.

Interestingly, this fellow we delivered service to, who didn’t seem all that impressed with our results, asked me to guarantee him speeds. Since I have no idea how service will be when it rains/snows, I told him I couldn’t guarantee speeds, but that I could gurantee better speeds than his other options :slight_smile:

Outstanding - I keep hearing good things about the Microtik stuff. I think I might order up a set to play with.