I kind of have a problem with my new point to point link.
The distance is not that great, only 1,2-1,5 km.
I use MT on PC`s, one side has PII(500MHZ cpu, 64 mb ram, wistron cm9 card, 24dbi Grid
antenna), on the otherside(PII 400mhz cpu, 128 mb ram, r52 radio, the same 24 dbi grid
antenna).
The thing is, i tried it with standard freq and on 2393, i always get great signal, something
in the range of -48…-52, but the ping drops, the transfer ranges up to 9-10 mbps, practically the link
is not stable.
Tried everything, w/nstreme, w/o nstreme, compression on/off, i even lowered the power to 2 dbm.
Nothing seems to work like it should do.
Filip -
Looking at what you’ve said - I think I would first put the cards at default power and defaut data rates.
It also sounds like you may have a noise problem. Have you ‘looked’ through the channels to see what the noise floor is on each channel? If not do so, if so then find the quietiest channel.
You can also try using the 5 and 10 Mhz channels. Though this will cut down your throughput it may give you a steady channel to run your system on. If you can’t get the noise level down try switching the polarity of the antennas…you probably have them in vertical polarization right now, switch them to horizontal - that might give you a quiet channel or two.
What are you using to measure bandwidth? The MTs themselves? What kind of encryption are you using if any at this time?
Once you find a quiet channel. Open the frequency window, ie, start at 5Mhz, then 10Mhz, watch the noise level…continue to check throughput and ping (without nstreme), I use the flood ping command to fire about a 1000 pings through. That is generally a fair test.
Once you have it all working then turn on nstreme and your encryption, etc as desired… At this point if you want to select default data rates select one below whatever your max TX/RX rate the radios show they are working at.
Hmm, i havent thought about the polarity of the antennas, will try that tommorow.
this is a screenshot on the client(station) side, this is with radios set to 2dbm, if i run theirs default power values, at 17 dbm, the signal rises to -48
the ping seems stable, but if i rise the packet count, say 150 bytes, i have like 10 drops on 1 passed ping
Filip -
Why are you using MAC ping? MAC does not work all that reliably…it is more just to see if something is there or not. You need to use IP based pings and bandwidth tests.
mcozio is right - do not set the ack time - let MT do it. I’ve run these systems for years and rarely do you have to set this. MT can handle it, and after you have it setup and working well, and after you have run data through it at various speeds and monitored what MT sets this at do you even want to attempt to set it.
Well you have a very good signal to noise ratio, about 30dbi, changing over to horizontal polarity won’t help much more. You can try it though…
Set up your system IP based, routed (not bridged) . I suspect you are not using IP based testing only MAC addresses… Once done, then run bandwidth tests. See what MT says is you maximum TX/RX speeds. Set you radio TX/RX rates one less than this. That should keep the radio stable. Some might reccommend that you set it two under, i.e., MT says TX speed of 48Mbps, one below would be 36Mbps, two would be 24Mbps. You’ll have to see what works best for you.
galaxynet - I just told about ack, not about it is set manually - too good signal may cause problems - it should be about -60,
next thing - are there any others AccessPoints in 2,4 ghz ?
if you have cm9 card - it take about 15min to built 5ghz antenna from beer can
I tested a link for 7,5km - one side panel 23 , 2m rf240 and atheros 5213a , from my side sparklan 5213, 2m rf240 -80 and with parabolic dish 60 -75 and 90cm -64
tested with hands w/out stable hadles so could be better
