Atheros Long Distance Issues - No data passing as well

[jbland]

I have a PTP that I'm trying to use an atheros 5.8, channel 161 to be exact.

Atheros MiniPCi on both sides, 29dbi Pac Wireless Dishes. The Ack Timeout on the AP is set to 203 and the client was 160. Version of Staros on both sides are 1.13.3b9.

The distance of the shot is 13 miles or 21km. What I'm surprised at is the low signal I'm seeing. 1 Unit is mounted and the other is on a tripod for testing. I put the tripod about 1 block away and was seeing -65 for signal. I then drove out about 6 miles and connected at about -78. At 13 miles I got -88. I set the essid, channel, and ack timeout, country code, Ap/client/forced to 802.11a, everything else is auto or default. regardless of my test ditance the rate is always 6 not sure why.

My problem is that all the calculations I've done (YDI,Electrocom) says I should have -65 for the 13 mile shot. This is not a permanent mount so I would take -70 and would have been happy.

Oops almost forgot cable loss. I have 20 foot of LMR 400 for one link and about 2-3 feet for the tripod.

Questions:
1. Are you still seeing poor signal for long distance with StarOS?
2. Does my calculations on link sound about right?
3. What is the basic requiments to setup to get StarOS to pass data? I can associate but can't ping the AP, does the MAC have to be in the allow list?
4. What are optimal settings for the atheros card for this link?

[bkehoe]

Try using an ack timeout value of 800 or so - unlike mikrotik, 1 = 0.25us with staros, so you multiply the values by 4.

[lonnie]

The beamwidth of the parabolic antennas will be very narrow. Are you fine tuning the pointing at each end for the shot?

[bobbyc]

I plan on mounting my radios right at the antenna (radio pigtail directly into antenna) and mounting them in a nema enclosure that is right at or on the antenna. I've read posts on the wisp list that individuals have measured dB loss on N-connectors and found 1.5dB of loss per connector. That, plus the 1dB per 10' you loose using LMR-400 at 5.8ghz, is going to keep me from using any cable lengths at all.
Lonnie is right that you are going to need someone looking at the association list to relay the signal levels to you while you are fine tuning the dish alignment at EACH end.
Bob C

[Skaught]

I used to build commercial 6ghz links with 6 foot dishes and aligning those sometimes took days.

Try a 38ghz link with 2 foot dishes. You almost have to hold your breath so as not to jostle the dish and take the link down. They reminded me of some laser links I did.

The 4 foot dishes are not as touchy but still require a fair bit of patience.

[lonnie]

Something we have recently discovered - start the ACK time at 9,000 and work down until you find the sweet spot. Please report back the values that it quits at and what makes it work.

We are finding that a number just 2 or 3 lower will make it not lock. It is still a trial and error method and once we get the formula worked out, you'll simply enter the number in miles.

[jbland]

Can you provide some guidance? After setting the Ack timing what consitutes a good timing value and what is bad (not working)? Is there an easy way to tell what is working best?

[lonnie]

I did some testing and at 5 km and under it was a very sharp curve, with as little as a drop of 2 making it not even link up. If you can find the points that it does not associate at I would appreciate hearing those numbers and what you set to in order to make them run.

I would add about 20% to the value that makes it associate and you have a good margin.

[ginovilla]

I have gone form 400 to 9000 on my 7 mile link without seeing any efects on rssi or thoughput

Gino

[lonnie]

Once you have the number high enough it really should not matter how high it goes. I am keenly interested in finding out the actual drop off point at which it will not connect, so drop the numbers below 400 and tell me what it quits at.

[jbland]

So far I went from 800 down to 400 . In fact I got 2db of signal going from 800 to 700. My link is 12 miles and here is what I got. I'll check the max tomorrow.

Lowest was 500, and this was barely associating. Barely is that it associated but after about 15 seconds the idle time kept counting up.

-James