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changeip
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Re: Solving 20km wireless link issues

Sun Dec 20, 2009 2:28 am

Just an update. A few weeks ago I placed at the data center side a pacwireless 32db solid dish, single polarity as a test to see what happens. This increased the signal to -66 or so, a huge improvement. I also went up about 5 more feet. This weekend I am installing on both ends the pacwireless 32db dual polarity solids ($49 each on ebay!) and hope to be in the low 60's. Will post pictures and other info shortly. Thanks for the help everyone!
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RK
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Re: Solving 20km wireless link issues

Sun Dec 20, 2009 2:38 am

pacwireless 32db dual polarity solids ($49 each on ebay!)
Nice. Very nice.
They got more?
 
changeip
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Re: Solving 20km wireless link issues

Sun Dec 20, 2009 3:54 am

nope, the guy said he had 3. they were listed as satellite dishes, in the wrong category. he didn't know they were $280+ new :) these 3 were all new. cost me $300 total with shipping for 3 of them, yeee haw. The surplus seller said he got them from a lost shipping palette, so someone here is probably missing them : )
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Re: Solving 20km wireless link issues

Tue Dec 22, 2009 4:17 am

Just to cast my vote, the effects you are seeing sound just like what I have on my long links, which is the thermal ducting that was mentioned earlier. I see it most after a hot day, late at night when things start cooling off, but usually only when there is almost no wind.

The effects of thermal ducting can help or hurt you depending on which "layer" you are in. Think of it this way, when the layers develop, if both of your antennas are within the same layer, your signal gets "stuck" in the layer and it helps increase the signal since less of it is getting lost in the fresnel zone. If your antennas happen to fall into different layers, it can hurt your signal as much as it helped.

I can watch my 35 mile 5ghz link. Normally it hovers in the -75 area. Late at night, I can watch it go into the -90's and start to disconnect.... In a matter of minutes, it can be back to the -70's, and actually increase into the -50's. As the layers disappear, the signal levels back out around -75.

Happens like clockwork. About the only solutions I know of are to throw more signal at it (bigger dishes) or add a repeater in the middle.

Joe
 
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Re: Solving 20km wireless link issues

Tue Dec 29, 2009 2:17 am

This has been a very long thread. Please update us with your new antennas. I am sitting on the edge of my chair waiting to see a resolution...

In my experience, fixing a very difficult problem will teach you more than you ever expected to learn. That is the saving grace of these kinds of problems. Everyone following this will benefit from your frustrations.
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Re: Solving 20km wireless link issues

Wed Jan 06, 2010 1:56 am

If your Fresnel is really 0.3F1, then in my opinion that is your problem.

It is my opinon that for a reliable link you should have 0.8F1. I consider (again my opinion) 0.6F1 to be the absolute minimum.

Given your description, I would both increase the height of the antenna at the data center and also if possible at the water tower.

Also if possible move the antenna at the data center so that you are not pointed across the metal roof, I have had many problems in the field going over metal roofs in that manner.
 
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Re: Solving 20km wireless link issues

Wed Jan 06, 2010 8:06 pm

I have replaced both ends with PacWireless 32db dual polarity dishes. I also increased height at the data center by about 4-5 feet, and on the water tower about 2-3 feet. Signal went from -80's to -50's. I have a feeling those PacWireless 29db grids aren't really 29db. Going to the data center over the next week to flush out installation and will take more pictures and post the final solution. Will be testing nstreme2 today with the dual polarity dishes, hopefully there is enough isolation to not cause me problems. BUT - WOOO HOOO, finally a link that is working. I'm hoping to get 80-120mbps from the data center into the wireless mesh, could be a pipe dream : )

Oh yeah, when ducting happens the signal goes down into the -40s now...

Thanks everyone for the help. I really appreciate it.
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Re: Solving 20km wireless link issues

Wed Jan 06, 2010 8:27 pm

I have replaced both ends with PacWireless 32db dual polarity dishes. I also increased height at the data center by about 4-5 feet, and on the water tower about 2-3 feet. Signal went from -80's to -50's. I have a feeling those PacWireless 29db grids aren't really 29db. Going to the data center over the next week to flush out installation and will take more pictures and post the final solution. Will be testing nstreme2 today with the dual polarity dishes, hopefully there is enough isolation to not cause me problems. BUT - WOOO HOOO, finally a link that is working. I'm hoping to get 80-120mbps from the data center into the wireless mesh, could be a pipe dream : )

Oh yeah, when ducting happens the signal goes down into the -40s now...

Thanks everyone for the help. I really appreciate it.
I have used plenty of the pac 29's (probably 50 of 'em), they are perfectly good antennas. Improving your fresnel is what actually helped.

The importance of good fresnel cannot possibly be understated. It is absolutely the single most important property of any link!
Last edited by nickb on Wed Jan 06, 2010 8:49 pm, edited 1 time in total.
 
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Re: Solving 20km wireless link issues

Wed Jan 06, 2010 8:37 pm

I vote for sticky :roll:
This thread is very helpfull and usefull.
Renato Bernardi

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Re: Solving 20km wireless link issues

Thu Jan 07, 2010 7:19 pm

Assuming different antennas but exact same alignment and heights, that improves fresnel because of the degree of beamwidth correct? Going from 4 degree to 3 degree increases fresnel simply because its a narrower path?

Now I have the problem of RB433 w/ 2 radios and getting half speed when the other associates, but I'll keep that to the original thread if I can find it. Pictures coming shortly on the link...
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Re: Solving 20km wireless link issues

Fri Jan 08, 2010 3:48 am

Assuming different antennas but exact same alignment and heights, that improves fresnel because of the degree of beamwidth correct? Going from 4 degree to 3 degree increases fresnel simply because its a narrower path?
No, the fresnel zone does not depend on the beamwidth of the antenna.
It depends only on frequency and distance.
 
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Re: Solving 20km wireless link issues

Fri Jan 29, 2010 2:25 am

Very interesting tread changeip.
Some pictures and last info would give it a nice end.
The tread is dead now for 20 days, any last info?

And yes, vote to make it sticky. This is a very educational topic for lots of us... well done!

R.
 
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Re: Solving 20km wireless link issues

Fri Jan 29, 2010 2:58 am

No, the fresnel zone does not depend on the beamwidth of the antenna.
It depends only on frequency and distance.
True. But the beamwidth does have an effect on the amount of energy transported in the LOS tunnel.
Thus with the same Fresnel and same radio output you get better signal (=more energy) on the other end. Thus higher readings. The negative impact of the ´blocked´part of the Fresnel is the same in % but since the amount of signal received by the other end is higher, you have better signal levels.

Now before we think this can then also be achieved by just more power on the transmitter. It is not the same.
Bigger dishes or bigger mesh antenna's are not only better in converging (´tunnelling´) the signal, thus delivering more energy at the other end, but are also better in ´hearing´ in its focus direction when receiving the signal. So you win twice here instead of only once with higher power outputs. Aiming becomes more important now.
But this is an important element some of us forget. Just increasing power is usually not the way to go.
(Apart from the fact that most radios perform better under mediate power settings then max. settings. If possible leave them at default or drop a bit.)

Look at this radio link issue as an adjustable focus torch that you use to signal a guy with binoculars some miles away.
If your torch's light beam is wide you'll have a nice light close to you but your guy at the other end won't probably see you with its bare eyes, special if there are lots of other light around you and him.
Now converge the beam of the torch to the max and he might pick up the light if you point at the right direction. Your light will stand out compared to other surrounding light seen by the ´looker´.
It will make it all much better for the distant guy if he then starts to use binoculars.

You could also put a much higher voltage to the lamp of the torch when not converged yet. Your other guy will then also pick up the light from you, just before you bulb burns....

In the ´receiving end´ (the ´looker´) imagine the following:
When he uses bare eyes or a cheap binocular, he will only see the torch if it is focussed heavy and pointed in his direction or when it is unbelievably bright. But at the same time he will also see other lights in its surroundings, like a car using its head lights while hunting rabbits.... (Doppler radar hunting for rain...).
Now, if your ´looker´uses a telescope he will pick up your torch easy if he is pin pointed to the torch while probably doesn't even see the hunters car any more. You can even put some lesser volts to the bulb to extends it life time (not too low, the bulb then also start becoming to work less and shortens its life time. Just like a radio.)

In using the high dB dish antenna's you do both. Converge the beam and maximise the hearing while at the same time keep as much of unwanted signal out of your receivers (so lower noise level)

The only risk here is that when a strong signal happens to fall into the antenna and the signal is picked up by the receiver it might blow its receiver circuits.
(Imaging the ´looker´ uses the telescope to look comfortably at the torch and then lightning strikes direct in your path of vision. Worst case is he looses sight for ever.... In radio terminology, it will damage your receiver.)

So now you also have a tip to ´blow´ your competition out of the sky.
I know, not the purpose of this topic, but imagine you are the competition...... be aware!
 
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Re: Solving 20km wireless link issues

Fri Jan 29, 2010 11:38 pm

Very informative post, I will be interested to see how it turns out.
 
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Re: Solving 20km wireless link issues

Wed Feb 17, 2010 2:27 pm

have you solved your issue?

1. try to add 50m antenna pole on the side which is lower (to avoid power line radiation. the height is depended to their transmit voltage)
2. try to reduce the 20mzh channel to 5mzh, if that helped then use a more powerful card or use a amplifier.
3. try to replace your antenna where you have a sharp (more towards 90 degree angle on those powerline)

We had very much the same problem as you did a few years ago.
when there was a high power line in the path similar to what you have in one of the photos.

if the power line has angle it will do unknown and strange behavior which no-one may never know.

although in these scenario we did a test with dual antenna and 11n card and it did greatly improved the speed and the signal.

Beside installing a tall poll at low end I can't recommend anything.

to test , you can use a GI pipe and use a temporary cable to hold it for signal testing and see if going above the power line will help or not...

in our case 50m above the power helped a lot.


Good luck
 
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Re: Solving 20km wireless link issues

Mon May 31, 2010 8:04 am

Kan you please send me the google earth place marks and the hight of each antenna from ground I would like to run it in a tool we have

you can mail it to erastus at theweb.co.za

It would be very nice to run it in our simulator. Mark each spot with place mark and then mail the place mark
 
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Re: Solving 20km wireless link issues

Sat Jul 17, 2010 7:25 pm

Hello, people.

Reading the entire posted. I realize maybe a design error in the pacwireless new grids. I recently installed a new wireless network with about 6 25km distance links. Each site has the same config as the others, same antenna, same board, same minipci. I found out my links barely can get -78dBm Rx signal. I have test another minipcis and have the same signal strenght. The only option left is to try another antenna to test.

I would like to ask you people to share your experience with these grid antennas.


Best regards..
 
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Re: Solving 20km wireless link issues

Mon Jul 19, 2010 8:41 pm

Hi changeip, which software is it? that graphs the signal from RB's...
I am starting to think its freznel zone effects as well, but really can't figure out why it would increase tremendously every once in a while:

Image

If it was the roof reflecting would it do what I see above?

If it was the weather (temperature inversion) would I see it only happen for 30 mins or so as shown above?

Now if it was another source putting off RF interference I would see the above. Is there an easier way to test that / track it down?
 
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Re: Solving 20km wireless link issues

Tue Jul 20, 2010 10:05 am

MRTG
No answer to your question? How to write posts
 
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Re: Solving 20km wireless link issues

Tue Oct 05, 2010 3:44 am

Great thread.
I have an almost identical 5Ghz backhaul link. Much much better looking fresnel zone however.
There is a hill at approx the halfway point, not quite in the zone.
The link runs almost constantly at -66 both ends, EXCEPT on hot and calm dog days when the trees on the hill are giving off quantities of water vapor.
Then it drops to -74 to -76 and stays there until the wind comes up or the water vapor dissipates.
I totally agree with mramos and jcremin.
 
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Re: Solving 20km wireless link issues

Mon Nov 15, 2010 6:05 pm

Hello Forum Guru

Let tell you some facts based on your Radio Mobile information, per experience I have many Links working even with more distance using Mikrotik's without problems, but the whole idea of Radio mobile is to help to avoid you waste time deploying a link that won't work, the signal predictions are good in Radio mobile if all data in is correct and results are correctly interpreted.

I'm seeing many issue on your information posted:

1- You configured a maximum TX power of 27dBm, I'm not sure but I do not think this TX power is possible, maximum 25dBm depends of the Wireless card used.
2- Your received sensitivity is too good, for a link budget you have to be conservative so -93 dB is too good, you should configure on Radio mobile a little more conservative value like -86dB
3- Antenna Gain is important, also antenna pattern, so if you use the right antenna gain and the right antenna pattern then should be not poroblem, I can not tell if this correct based on your information without seein the whole prpject file.
4- The signal is blocked more than 50% on certain point of the path by a hill, you have to calculated the fressnel zone to verify this will be an issue or not.
5- Never deploy a link is you do not have a margin at least of 20dB's, on your Link budget the Profile shows on few dB's margin, so weather, atmospheric events make the signal fade a lot, so with the few margin calculated by Radio Mobile you won't have a stable link.

In summary Radio Mobile works only is all data is entered correctly and some extra conservative values are considered.

remember the law "Trash IN = Trash OUT"

If Link budget data is not entered correctly the link budget is useless, also if all is right link budget is also telling you never deploy a link if you do not have at least 20dB's S/N level to account for FADE
 
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Re: Solving 20km wireless link issues

Sat Jan 15, 2011 5:29 am

Go higher!!! metal buildings are mirrors for wireless. I dont know if you have any water ( as in lakes ) but they can have the same effect. The best thing is higher or move away from the metal building.
 
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Re: Solving 20km wireless link issues

Mon Mar 07, 2011 11:28 am

I would like to know the end result too, seems like the problem was still there?

When I was reading this, I seen the picture of the air conditioning unit.
Also seeing the graphs, where I believe it was between 4 am and 6 am where it got better....
My theory is that, since this building is a data center, that AC unit would probably be going most of the time, but possibly the days, as intermittent as they were, when the temprature falls low enough that AC is not needed in the building, but just use outside air, then it would shut down. Im sure the unit on the roof is actually an Air Make up Unit, not just an AC unit.

It would be interesting to see if the outside temp for that area fell low enough during those nights so that the AC compressor unit was not working, or even if that AC/ Air make up unit was shut down for that duration. The hot air exhausted from the unit may have been effecting the link, when it was off, it got better.

Hopefully we find out for sure if the link got better???

My OTHER Idea was that that may not be doppler radar ( Weather) It may be Radar for an airport? I had a couple links that were to the North of my AP, and in the direction of the airport, that ALWAYS had a very low signal, -78 - -84. at some point that same hardware was moved to locations south of the AP and even further away and the signals got up to -70. There was no LOS, there was trees that were taller then the height of the AP, and even a house litterally in the way of the shot. To be honsest Im suprised it works.... as for the advice of if there is less then 20 DB fade margin, dont bother setting up the link, well, I think its faster and easier to run the data in radio mobile, and see if it is remotley possible, then just set it up, after all you obviosley need the link, why else are you trying to get it to work?
 
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Re: Solving 20km wireless link issues

Mon Mar 07, 2011 5:52 pm

I did get this to work a long time ago - we ended up using the 3ft pacwireless dish on both ends versus the grid dish I started with. Its a very stable link now, almost 200 days uptime I think. The main issue was temperature inversions on the path. The link barely changes signal now with the 3ft dish, very solid.

Image
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Re: Solving 20km wireless link issues

Mon Mar 07, 2011 6:01 pm

Hi changeip, which software is it? that graphs the signal from RB's...
I am starting to think its freznel zone effects as well, but really can't figure out why it would increase tremendously every once in a while:

Image

If it was the roof reflecting would it do what I see above?

If it was the weather (temperature inversion) would I see it only happen for 30 mins or so as shown above?

Now if it was another source putting off RF interference I would see the above. Is there an easier way to test that / track it down?
sorry about hijacking this thread but what about that program that visually showed the fresnel zon and his link across the vertical slice of the land. what program is that and how do i get it :)
 
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Re: Solving 20km wireless link issues

Mon Mar 07, 2011 7:09 pm

sorry about hijacking this thread but what about that program that visually showed the fresnel zon and his link across the vertical slice of the land. what program is that and how do i get it :)
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Re: Solving 20km wireless link issues

Tue Mar 08, 2011 6:21 pm

Hi,,

Im make link for 36KM distance links :

2*RB433AH
2*XR5 with cables.
Dish 32db dual 90cm
antenna dual 32db

the link working very good the signal is :
You do not have the required permissions to view the files attached to this post.
Thanks!

Best Regards.


--------------------
If my answer helped you and my question good too, please give me karma
 
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Re: Solving 20km wireless link issues

Sun Mar 20, 2011 4:15 am

If this would not be enough, you can also try plugging in signal repeaters on specific spots which has low signal levels. This is pretty much applicable on schools which have class rooms with mobile phone signal jammers but if you still want a wireless internet signal, then might as well right. ^ your network looks really impressive if that covers the 36km distance.
 
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Re: Solving 20km wireless link issues

Fri May 20, 2011 1:43 pm

Greetings!

Does anyone have antenna templates for 2,4 and 5 GHz, that i can import in RadioMobile?
 
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Re: Solving 20km wireless link issues

Fri May 20, 2011 6:10 pm

Greetings!

Does anyone have antenna templates for 2,4 and 5 GHz, that i can import in RadioMobile?
If you join the Radio Mobile Yahoo group (mailing list), you can get access to the Files section of the group site at http://groups.yahoo.com/group/Radio_Mobile_Deluxe/ which has many useful antenna pattern files, including many patterns for Pacific Wireless (Laird) antennas.
 
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Re: Solving 20km wireless link issues

Mon May 23, 2011 10:32 am

Thank you!
 
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Re: Solving 20km wireless link issues

Fri Jul 22, 2011 10:39 am

I am glad seeing this post which has explained the Solving 20km wireless link issues. Well, I am looking for some experts for Data Center Relocation. Please do share some information regarding that.

===============
Data Center Relocation
 
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Re: Solving 20km wireless link issues

Wed Sep 14, 2011 10:44 pm

tgrand is right about the power lines. Don't forget that electromagnetic field around the cables may also change the direction of the beam or create out of phase waves.
If you have reflected waves that are out of phase, the RX signals of both points will be different.
Looking at the pictures, I don't see something in you even frensel zones.

Do you observe these changes in RX signals to be connected with the weather conditions, for example with rainfall ?
 
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Re: Solving 20km wireless link issues

Mon Sep 19, 2011 11:18 pm

Hi,,

Im make link for 36KM distance links :

2*RB433AH
2*XR5 with cables.
Dish 32db dual 90cm
antenna dual 32db

the link working very good the signal is :

Whats the throughput you have on that distance? the REAL deal.
 
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Re: Solving 20km wireless link issues

Tue Nov 01, 2011 3:57 pm

Found this one the internet:
http://j-walk.com/other/wifispray/
Should it improve long-range links and should I try to make an automatic dispensing system?
 
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Re: Solving 20km wireless link issues

Tue Nov 01, 2011 4:08 pm

Can you tell me how I can start 20 Km wireless project using mikrotik instrumentation Plz I am in hurry
thanks
 
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Re: Solving 20km wireless link issues

Wed Dec 07, 2011 12:18 am

Image
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Re: Solving 20km wireless link issues

Wed Dec 07, 2011 7:21 am

Mr. mramos

Why you did not mount the antenna in considerable height?
How far your second antenna?

thanks
 
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Re: Solving 20km wireless link issues

Wed Dec 07, 2011 10:32 pm

Why you did not mount the antenna in considerable height?How far your second antenna?
Hi ...

Well, it's not really necessary. Trees at this site have more than 15 .. 20m height. Signal path is 1.6Km. This antenna height have some clearence between the smaller trees leaves and the taller ones (like a window).

I only posted this chart to complement some old posts about moving antenna mount along a flat surface versus the effects reflection of radio signal on such surfaces in front of the antenna can cause.

But even with signal variations this link is in production this way for almost 2 year, uptimes normally more than 1 week. If any disconnection occurr it's restored in a fraction of a second.

I only "fine tune" its position because I installed there a second grid antenna to give access to 5 or 6 small properties 4Km away and this second antenna was obstructed by a water reservatory. As I need to move it from the old position I decided to search a new spot where those signal notches are smaller than I used to have at the original position.

A bigger tower - to clean up radio path - must have at least 25m. Too expensive to feed 10 customers :D

Regards;
Marcus Ramos
Electronics Technician
(Microwave HW, RF, antennas, propagation)
S.Paulo - Brazil
 
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Re: Solving 20km wireless link issues

Thu Dec 08, 2011 7:29 am

Mr. mramos
I have to construct a wisp but I am not sure of the following:
1- Mounting a 24 dbi grid (2.4 G Hz) on a house building height (8 Meter) and the second 24 dbi antenna on the same height with 14 KM far away (Distance between both antennas) but no obstacle between them.
behind these antenna I have 26 dbm transmit power wireless router.
so can I have 26 MB or above bandwidth?

thanks a lot
 
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Re: Solving 20km wireless link issues

Thu Dec 08, 2011 8:43 pm

Mounting a 24 dbi grid (2.4 G Hz) on a house building height (8 Meter) and the second 24 dbi antenna on the same height with 14 KM far away (Distance between both antennas) but no obstacle between them.behind these antenna I have 26 dbm transmit power wireless router.so can I have 26 MB or above bandwidth?
I don't think it will work.

Even without obstruction in the path there will be earth curvature itself. Small at 14km anyway but it's there. The main obstacle is fresnel zones blocking.

On such path at 2.4GHz to clear up at least 0.6 F both antennas must be at ~22m height each side. If it was 5.8GHz, for the same 0.6 F antennas must be ~16m each side.

Regards;
Marcus Ramos
Electronics Technician
(Microwave HW, RF, antennas, propagation)
S.Paulo - Brazil
 
salytwo
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Re: Solving 20km wireless link issues

Sat Dec 10, 2011 11:18 am

Mounting a 24 dbi grid (2.4 G Hz) on a house building height (8 Meter) and the second 24 dbi antenna on the same height with 14 KM far away (Distance between both antennas) but no obstacle between them.behind these antenna I have 26 dbm transmit power wireless router.so can I have 26 MB or above bandwidth?
I don't think it will work.

Even without obstruction in the path there will be earth curvature itself. Small at 14km anyway but it's there. The main obstacle is fresnel zones blocking.

On such path at 2.4GHz to clear up at least 0.6 F both antennas must be at ~22m height each side. If it was 5.8GHz, for the same 0.6 F antennas must be ~16m each side.

Regards;

I am using this calculator : http://www.afar.net/fresnel-zone-calculator
I use equal height antenna section with 0.6 Fresnel zone.
This calculator give 12.9 meter height.
so if I change 8 height to 12.9 it will work Am I right?

thanks a lot brother
 
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mramos
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Re: Solving 20km wireless link issues

Sat Dec 10, 2011 12:07 pm

I use equal height antenna section with 0.6 Fresnel zone.
This calculator give 12.9 meter height.
so if I change 8 height to 12.9 it will work Am I right?
Well, I took a look at this calculator.

12.9 meter is the radius of 0.6F at the midpoint.

But you have a 14km path so it's necessary to add earth curvature.

Assuming it's a perfect surface (like a path over a calm lake), according with this calculator both antennas must be at 15.3m height.

At this height 0.6F at the middle path will have 0m clearence. Rising both antennas to 16m will give you 1m clearence to 0.6F at the middle of the path.

The numbers I gave you before came from another tool (radiomobile) but I simply picked up some geographic area with a "flat" surface (a beach) near my hometown. But I'm not sure how accurate RM can be in this case.

Regards;
Marcus Ramos
Electronics Technician
(Microwave HW, RF, antennas, propagation)
S.Paulo - Brazil
 
salytwo
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Re: Solving 20km wireless link issues

Mon Dec 12, 2011 8:03 am

Can you tell me what do you mean by 1m clearance?
I understood that I have to add the objects reside in line of side eclipse like tree or some unequal earth
Am I right?

thanks
 
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mramos
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Re: Solving 20km wireless link issues

Mon Dec 12, 2011 12:06 pm

Can you tell me what do you mean by 1m clearance?
I understood that I have to add the objects reside in line of side eclipse like tree or some unequal earth
Am I right?
Image

1 meter clearence is the distance between terrain and the lowest part of above elipse (where at this wikipedia picture the letter "P" is). In your case I assumed a perfectly flat terrain.

And - yes - you have to add those objects and terrain roughness.

Regards;
Marcus Ramos
Electronics Technician
(Microwave HW, RF, antennas, propagation)
S.Paulo - Brazil
 
salytwo
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Re: Solving 20km wireless link issues

Mon Dec 12, 2011 4:09 pm

Thank you mramos I hope you fine and doing well,
If I have clear line of site and 24 dbi grid antenna with 23 dbm output power using 2.4 Ghz unlicensed. I will be able to transmit at least 10 MB or not?

If I use 5.8 Ghz can I get 10 MB or still not?

thanks a gain
 
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mramos
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Re: Solving 20km wireless link issues

Tue Dec 13, 2011 12:33 am

If I have clear line of site and 24 dbi grid antenna with 23 dbm output power using 2.4 Ghz unlicensed. I will be able to transmit at least 10 MB or not?

If I use 5.8 Ghz can I get 10 MB or still not?
Of course. If there's no obstruction nor interference I thing even using 10MHz channel + NV2 (or Nstreme) you can reach 10Mbps. If the cards you choosed are N capable, better. Most of my cards at 2.4 (and 5.8 in near future) are R52nM.

And if you want a PTP solution, there's Groove for 5G (and 2 GHz in some time I read). No cables, no pigtails, just attach them at the antenna connectors and that's it.

Take a look at some examples at the forum, several success stories > 20Mbps.

Regards;
Marcus Ramos
Electronics Technician
(Microwave HW, RF, antennas, propagation)
S.Paulo - Brazil
 
salytwo
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Re: Solving 20km wireless link issues

Sat Jan 07, 2012 1:44 pm

Hello dears,
How I can make surveillance setup for my WISP using google map or something similar?
this action will help to mount the antenna truly.

thanks
 
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Re: Solving 20km wireless link issues

Fri Jan 20, 2012 5:28 pm

wow Nice job !!! congratulation
 
christyjame
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Re: Solving 20km wireless link issues

Sat Feb 11, 2012 9:23 pm

Hi Seniors . . .

Thanks for useful post ,yet i experienced with this issue on 45km link backhaul,
Thanks again to my seniors.
Christyjame

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