 BigCreekGod Is Good.Premium
join:2002-06-25
Heber Springs, AR | 900MHz at 9 miles and some trees One of the clients that would be an important "anchor tenant" is 9 miles away across a fairly flat valley floor and has a treeline of oaks about 3 deep right next to his house. The valley floor is generally forested also. The tower would be on a hill about 400' above the valley floor with a sector pointed at the client in a P-t-MP setup.
Any thoughts on probability of success and what antenna on the client end is most likely to give a stable link?
I'm still deciding between Canopy, Trango, etc.
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SBC Pro Static DSL; Linux. Terrific wife & kids; live on a farm by Big Creek. Software & network consultant. |
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 DaDogsSemper VigilantisPremium
join:2004-02-28
Deltaville, VA | +36 dB EIRP (xmit max legal)
--90 dBm Receive sens
+12 dBi Receive gain
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138 dB Link budget
-115 dB Path loss
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13 dB Fade Margin
This presumes NO LOSSES in the feed systems.
Looks like you will be able to make the link, just build it right and pray that you don't have any interference in that valley.
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»www.freeantennas.com |
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| reply to BigCreek
Whichever vendor you choose, go with the connectorized CPE. You may need to play with different antennas to make this work. The standard 10dBi panel (built into the Trango) is a good place to start but a high gain yagi is good to have around.
We did a 5.5 mile install with trees on the CPE side today and couldn't see the tower. With the built in Trango antenna we had a -80dbm signal but the speeds sucked. (Mostly due to interference.) Dropped a 13dBi yagi in and signal dropped to -77dBm and speeds were a rock solid 2.2 Mbps down and 1.5 Mbps up with TCP.
Our Trango APs do have the twice or more daily reboot issues but no clients have complained. However, our next 900MHz deployment we are moving to Canopy. |
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| reply to BigCreek
The use of a yagi will help this work the best. The only problem we have found is that if your area gets snow or ice the yagis do not work well outdoors. To combat that problem we have been installing the units in attics.
We just put in a link at 9.7 miles through thick pine trees on the cpe end with a Trango unit with a yagi. Before we put on the yagi the link was usable but the RSSI was not great.
The unit is in the attic shooting through the gable end of the roof. We are getting a -72 RSSI and the link is quite good. Our tower is up on a mountain so our results may not reflect what you will see. Remember that 900 has a rather large fresnel zone. We find that you are far better off using a yagi if the link is anywhere near marginal. Otherwise when the weather changes you may be in for a nasty surprise. |
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BigCreekGod Is Good.Premium
join:2002-06-25
Heber Springs, AR | reply to Believer
Thanks for the answers. Sounds like a high probability of success.
said by Believer:Our Trango APs do have the twice or more daily reboot issues but no clients have complained. However, our next 900MHz deployment we are moving to Canopy. Could you elaborate more on the decision to switch? (I was somewhat leaning toward Trango.) Is it just the reboot issue?
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SBC Pro Static DSL; Linux. Terrific wife & kids; live on a farm by Big Creek. Software & network consultant. |
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| reply to BigCreek
Canopy has more throughput, ability to GPS sync radios, higher transmit power which means we can use lower gain yagis, no reboot issues and cheaper CPE in quantity. |
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| reply to BigCreek
Another with Canopy you don't have consistant problems with buggy firmware and support that denies the issues when you first contact them. |
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| reply to BigCreek
Trango has a high number of buggy firmware releases and their support has a history of denying these problems exist on initial contact. It's better now that you also deal with distributors but some of them aren't much better. |
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 John GaltForward, MarchPremium
join:2004-09-30
Happy Camp
kudos:3 | reply to wolfcreek
said by wolfcreek:The use of a yagi will help this work the best. The only problem we have found is that if your area gets snow or ice the yagis do not work well outdoors. To combat that problem we have been installing the units in attics. Use an antenna with a radome to keep the elements dry and ice-free.
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A is A |
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| reply to BigCreek
Ditto we just moved from the Trango camp to Canopy - fixes like forcing half duplex to fix what looks like an ARP cache overflow on the M900S Trango is just plain stupid. Waiting for the first Canopy delivery now - eta 3 weeks!... seems they're a tad popular. BTW - the Canopy CPE's may be cheaper in bulk but not one at a time :-( |
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John GaltForward, MarchPremium
join:2004-09-30
Happy Camp
kudos:3 | reply to BigCreek
said by BigCreek:One of the clients that would be an important "anchor tenant" is 9 miles away across a fairly flat valley floor... Based on the comments by DaDogs regarding the link budget...
Would it be better to make a PtP link to this customer and use "his" site as a springboard to servicing more clients in that area? Since he is an important client more effort to accommodate him might be in order.
I don't know what the particular circumstance is...but that might help your budget out, since the rules are different.
Some food for thought...!
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A is A |
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BigCreekGod Is Good.Premium
join:2002-06-25
Heber Springs, AR
2 edits | quote:
said by John Galt:
Would it be better to make a PtP link to this customer and use "his" site as a springboard to servicing more clients in that area? Since he is an important client more effort to accommodate him might be in order.
It's certainly a good thought.
But his location is pretty far out of the way and not a good one to distribute from. Plus it's his residence which brings up issues like power backup, 24 hour access, etc.
If the PtMP option doesn't work tho, it might be worth a dedicated PtP to get service there. |
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| reply to BigCreek
Trango's 900 will deliver more usable throughput and has the external antenna option for a 15dbi Yagi at the customer side of this link.
Shayne |
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| With Canopy moving to the Advantage Platform (4Mbps) on their 900 MHz gear I think Trango's now in the basement on "useable throughput" at 3Mbps aren't they ? Our other decision maker was that Trango looses throughput quick when the fade margin drops below 10db it seems. Canopy's Propaganda says they can run full tilt right down to 3db....A couple other reasons for not staying Trango were the bugs, the lower radio output and lower recv sensitivity. |
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| I heard waverider's next 900 firmware will get it up to 6 mb. |
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| Yeah but unless they've changed their design WaveRider doesn't support an external antenna does it ? |
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 aSicapplication specificPremium
join:2001-05-17
Wakulla, FL | reply to wispman
said by wispman:I heard waverider's next 900 firmware will get it up to 6 mb. But how much of the band will it eat up to deliver this?
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Teamwork is a lot of people doing what I say. | ircd.removed.us #dslr | Starband SRS m360 GE4 C4/S69 | Win2003/DualNIC | 802.11b |
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| reply to BigCreek
Where do you get a 900 mhz yagi with a radome? These antenna are between 4 and 6 feet long and we have not found any with a radome available |
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| reply to BigCreek
I'm a client on a Canopy 900 MHz system nearly 14 mi away. However, don't be too sure about the bug free firmware. We just rolled back from 7 due to issues when the tower has 30+ clients. The AP kept knocking us off.
Motorola says they may have a beta fix next week...hmm (They also denied they had any issues)
Jae |
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2 edits | Hi Canopy User:
How are things going with your Canopy now?
What did you mean when you said: "We just rolled back from 7..."?
I assume you had problems as a client, when the WISP you get your service from got 30 or more clients connected to the Canopy AP ? Has this been fixed?
Thanks, |
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