Read a lot of stories posted here about 900mhz capabilities.
Using 900mhz integrated radios, APs and SMs running 6.1 software. They DO NOT work well through foliage at all.
Situated in Southeast Texas with very little change in elevations (flat) but is called the “Big Thicket”. Running a 6 AP cluster atop a 100’ tower. Within LOS works absolutely wonderful. Have one site at 1.5 miles that connects but at -78dbm. Very weak. Other strategic spots around the 360 degree coverage within .25 miles NO connect.
By the way, Motorola response is that Canopy is not guaranteed to work through foliage. Think twice before investing in this equipment for that reason. We have actually many more sites that do not work than do with no support to remedy other than take spectrum analysis which was the beginning engineering effort to insure feasibility. But going to do it again.
Expectations have not been met with regards to Motorola Canopy equipment or support. It is becoming more apparent that this equipment cannot support our area.
If anyone can make suggestions other than changing the ‘transmitted power output’ explanation (established at 24 with integrated 12 db antenna) or segregate adjacent radios or take spectrum analysis, please advise.
Thanks in advance.
Read a lot of stories posted here about 900mhz capabilities.
I live in the southern mountains of New Mexico around 7000 ft. tall pines everywhere. I have had pretty good luck so far. I am using the connectorised versions of the 900 ap’s and sm’s. I only get an effective range from 5 to 10 miles per ap but that is mostly due to the mountains. I finally decided to put a 900 sm at my house 2 weeks ago. I mounted it on a tripod i picked up at radioshack with a yagi antenna. drove home and set it on the covered front deck. I could not even begin to see where the ap was I just pointed the yagi in the direction i thought it was threw the trees and turned it on. By the time i got the computer turned on it had already registered rssi or 1100 jitter 4 air delay is 4 miles. downlink set to 75% i get 1.5 down and 380k up at 50% i get 1meg up 1meg down.Two weeks later i have still not mounted it on the roof like i want to or even fine tuned it and still going. I can say i dont think motorola ever intended this to be 100% non line of sight but I think that it will get you in some areas that the other bands will not.
Good for you. But at this point I just do not believe you unless the connectorized units out perform these. I have 6 APs and 20 SMs all integrated and they DO NOT perform as stated.
All I’ve read so far is how it is simply plugged in and ‘Presto’! This is not true. I have too much invested (money and otherwise) in this to be telling a joke. I need helpful suggestions instead of success stories.
So far Motorola Canopy is not offering any real support but was adament about what their units were not guaranteed to do. In otherwords, Motorola is not confident that their units can actually penetrate dense foliage. My system indicates that this IS true.
Anyone have any new ideas of how I might improve this situation or deal with the issues prior to shelving the project? A spectrum analyzer will not solve this problem. I had the area surveyed prior to construction and no resulting interference was found. Another Motorola cop out.
This all constitutes a show stopper. One cannot run a WISP off equipment that performs as this does.
maby you could give us a little more info about your configuration so we could help you better
Thanks for the request attitude. I will try to give more info but do not know what else to give. I am down to signal gains, transmissions and receptions.
I do not have or know how to use a spectrum analyzer but think I am about to learn. I trusted and paid professionals to do this and based a financial commitment on their findings. Now I have to rework their work.
I think I am on to something at the moment that has to do with my tower construction and will be testing all day today. I will post the results when done. I want this to be successful, trust me.
If you have any specifics that you are curious about please ask.
You can’t get signal with 900Mhz at .25 miles away?? Something else is going on here. What kind of RSSI values are you seeing at that distance? What channels are each of your APs on?
I need more detail here… we’re on flat terrain here, too, and I have customers .5 miles away, hooked up and we’re shooting through buildings (a bit thicker than trees :lol:)
I would like to see the config page on your ap and sm?
900 will go through trees and alot of them on that. We are using a single connectorized AP which is mounted to a customers house(the omni is about 40 feet off the ground). No amps and nothing special on this site. Also 6.1 is on both AP and SM’s.
Below is a SM(intergraded) which is shooting through 1 mile of almost solid trees to the AP.
RSSI 1646 (-65 dBm)
Air Delay 41 (approximately 1.14 miles (6027 feet))
This 900 gear is awesome!
I would use the spectrum analyzer to see what kind of noise is in the area. Find a clear channel and use that. The tower you’re on isn’t also used for paging is it?
Both paging and cell towers are potential problems.
Something is definately wrong. I have been amazed with what these radios will do.
A few questions:
1. Are you using the CMM controller? this is the unit that provides power and GPS sync to the radios.
2. It sounds like you are using 6 AP’s for 360deg coverage. Each radio should get a specific sector id 1-6 with radios 1 and 4, 2 and 5, and 3 and 6 on the same frequencies. You can turn an AP into an SM, and then use it as a spectrum analyzer to look at the frequencies that the radio sees. Try to pick the three quietest frequencies
3. you should be using hardware scheduling - it makes a HUGE difference in the performance.
Let us know the answers to the above. We know how frustrating it can be. We are here to help
What happens if you turn off all but one radio, and then run a test?
We have one modem which is picking up signal through a stand of trees, a hill and a building at about 3km (2m) away from the tower.
Is there any high power lines that you are trying to shoot through? This makes a huge difference!!! I know I have driven around town and have seen tremendous EMI.
At one site in particular, I went to the customer’s house thinking I would be able to get a good signal with no problem. I went for the shot no luck! I was only 4 miles away and the ap was set for 12-WTF!!! Damn!!! So I put my laptop next to me , hung the Yagi out the window at the customer’s driveway and started driving towards the tower.Well I didn’t have to go too far, maybe 150 feet and boom 1400RSSI 3 Jitter. What was the difference? The High power lines above (i’m not an electrical engineer, but it was the main feed wires for the area, noticibly larger). I pulled the truck over and backed up- the signal dropped- scanning, scanning and more scanning. I put the Yagi out the window directly under the wire no luck, past it by 5 feet, REGISTERED. I did this again and again (not for fun) same results.
I don’t know if this will help, but I thought I’d share with everyone…Zwinn_root
1. Yes, we are using a CMM.
2. We’ve been contacted by a Motorola engineer who is familiar with our problem. We’ve configured the APs/SMs to broadcast/receive on the quietest frequencies under his instruction. It looks like it has helped to gain some distance, but we still have testing to do.
3. We will be switching to hardware scheduling Monday, also under the Motorola engineer’s instruction.
Thank you for the suggestions. We’ll keep everyone posted on results.
We’ve witnessed the issue that you mentioned concerning power liines. If close to transformers, the EMI appears to interfere w/ the SM’s reception. But, as you said, simply moving the SM a few feet corrected the problem. So, yes, this is something that we keep in mind during testing.
Thank you for the post.
…A thought on hardware scheduling…
It is my understanding that it increases throughput. But, does it have a noticeable positive effect on signal reception? We’ve been told by Motorola that it actually increases jitter, which is a negative.
I really appreciate the response and suggestions.
I also appreciate the Motorola engineer that took it upon himself to contact me to help resolve the issue, when the front-line support failed. I’m feeling more positive about the situation. We’ll see how things go over the next week or so.
Thanks again to all.
I have not seen hardware scheduling increase jitter, but I will defer to the Canopy Engineer.
I would think that with dense foliage, you “should” get up to 4-5 miles with 900MHz depending on the types of trees. Beyond that the trees just soak up all the RF.
I am glad to hear that you are closing in on the source of your problem.
Hardware scheduling at 2X data rate will increase jitter. This is because it is running in 4-level opperation mode. This is similar to when you see high jitter rates in backhauls.
I hope the testing is going well after the changes!
our experience with 900 is it works very well over the horizon. We have several sm’s at 18-19 miles nlos. It also has poor foliage penetration if trees are up close to the sm. I have several sites where we aren’t able to get 2 miles though woods in southern Indiana.
Each of you have covered issues now known and effective in our area. We are very appreciative. Thank you.
The equipment is definitely not plug and play but probably as best as can be acheived until technology advances.
It has been very frustrating and looks as if I will have to remove some of the APs due to no reachable customers in certain directions. I was trying for 360degree coverage. Sales persons are typical sales and have painted a picture that just is not true.
Todays testing will, again, be to determine which directions that I can supply coverage in this circle. It does not look even close to being a business sustaining endeavor given the prices of Motorola Canopy and tower structures. The customer base is here, but there has to be a higher ratio of connectivity than we are seeing. Then try to compete with the ever advancing cable guys and it looks very dismal. (we are not even established and they are already knocking on the doors of our area)
We have connected at some spots up to two miles now. This is the exception, not the rule, being very scattered and usually not at a prospective customer site.
We had some tower sway that once stopped increased our distance. Now, I am concerned about height since we lowered the 15 foot mast. The cluster rests at 95 feet. I am considering a 125foot tower but must be convinced that performance will be drastically improved as we cannot continue the financial drain.
Anyone with height issues or knowledge please offer some advice regarding this issue.
Kindest regards to all.