RF interference from wind turbine??

[SpecialistEnergy]

Hello all,

I have a customer who wants to install an internet bridge. The equipment is quite cheap if you use the 5Ghz frequency, but to save costs I would like to put the receiver on an existing wind turbine mast, which has a 2.5kW turbine on it.

My question is, would the turbine motor be likely to cause RF interference with the receiver? It would be mounted about 3 mtrs below the motor.

The salesperson for the receiver says no, I'm interested in other opinions.

Thanks for any help...

Ben

 

[Pete999]

Hello all,

I have a customer who wants to install an internet bridge. The equipment is quite cheap if you use the 5Ghz frequency, but to save costs I would like to put the receiver on an existing wind turbine mast, which has a 2.5kW turbine on it.

My question is, would the turbine motor be likely to cause RF interference with the receiver? It would be mounted about 3 mtrs below the motor.

The salesperson for the receiver says no, I'm interested in other opinions.

Thanks for any help...

Ben

Can't help I'm afraid

 

[Leesparkykent]

I've deleted your other duplicate thread...please stick to one as can get confusing. Cheers Lee

 

[Pete999]

I've deleted your other duplicate thread...please stick to one as can get confusing. Cheers Lee

OK couldn't remember posting something similar, sorry Lee.

 

[RWJ]

You need someone with a spectrum analyser.
I was going to suggest a chepo TV dongle SDR but they only go to about 1.5 / 2 ghz

 

[static zap]

Other thought , do they cope with a bit of microphony .
Rubber mount ?
( Mechanical vibration .. not tried beating one with a rubber stick !)
Remember some transmited mechanical noise on a local towerblock .(may have just been reflected sound,from blades - poor windows )

( Moving blades getting in reflected signal paths may get interesting )

 

[SpecialistEnergy]

( Moving blades getting in reflected signal paths may get interesting )

I will mount the receiver below the blade tips, and its in a very rural area so little to interfere with it...

 

[dmxtothemax]

why don't you try it and see ?

 

[SpecialistEnergy]

why don't you try it and see ?

I think I'm getting to the point where I'll have to - but it will cost my client about £750 so it would be nice to have some confidence it will work without telling him there may be another couple of hundred on top for another pole to be put up

 

[seltechpc]

A cheap and cheerful method is to use a broad bandwidth radio and spin the dial and listen for any change in the received signal with the genny running and stopped.

 

[UNG]

A lot will depend on the radio propagation of the antenna you intend to use as to how far below the blade tips you will need to be to avoid fresel zone incursion of the radio path.

 

[SpecialistEnergy]

A lot will depend on the radio propagation of the antenna you intend to use as to how far below the blade tips you will need to be to avoid fresel zone incursion of the radio path.

Could you explain more? And offer any advice on how much lower?

 

[Strima]

We had an intermittent fault on a wind farm microwave link. Every so often there would be a very short but repetitive transmission break that was messing with the backhaul.

When the wind changed direction the head would rotate and the blades were blocking the link as they spun, the link installer got some grief for that one...

 

[SpecialistEnergy]

Luckily the prevailing wind will put the blades on the other side of the mast to the receiver for the vast majority of the time, but I want to avoid the problem entirely because the link will be for general internet use not simply data logging info. I am making a bridge from someone with a Fibre connection to someone else on a very poor broadband connection miles from the exchange.

 

[UNG]

Could you explain more? And offer any advice on how much lower?

I'm assuming you are using directional antennas to facilitate this link

Have a look at this
Google Image Result for https://upload.wikimedia.org/wikipedia/commons/thumb/7/74/Sidelobes_en.svg/220px-Sidelobes_en.svg.png - https://www.google.co.uk/imgres?imgurl=https://upload.wikimedia.org/wikipedia/commons/thumb/7/74/Sidelobes_en.svg/220px-Sidelobes_en.svg.png&imgrefurl=https://en.wikipedia.org/wiki/Antenna_(radio)&h=220&w=220&tbnid=mgCalFGWAlhSWM:&tbnh=160&tbnw=160&usg=__d-WST1OU6u8EBTAagtDiW1ZK-uc=&vet=10ahUKEwiMgqnd9-rVAhWCZVAKHb6xB4IQ9QEILDAA..i&docid=iTS-STuTTmBDjM&client=firefox-b&sa=X&ved=0ahUKEwiMgqnd9-rVAhWCZVAKHb6xB4IQ9QEILDAA#h=220&imgdii=mgCalFGWAlhSWM:&tbnh=160&tbnw=160&vet=10ahUKEwiMgqnd9-rVAhWCZVAKHb6xB4IQ9QEILDAA..i&w=220

As shown in the pictures the main lobe of the radio wave generally looks like a rugby ball and is surrounded by side lobes ideally for a good radio path you would want to avoid any incursion into the first side lobes

 

[SpecialistEnergy]

I'm assuming you are using directional antennas to facilitate this link

well I'm using kit that has been designed for the job - Ubiquiti Loco M5 from memory

 

[SpecialistEnergy]

I'm assuming you are using directional antennas to facilitate this link

well I'm using kit that has been designed for the job - Ubiquiti Loco M5 from memory

 

[UNG]

Have you used the Link simulator software to calculate the link performance should give you a good indication of what you can expect from the radio kit

 

[SpecialistEnergy]

Have you used the Link simulator software to calculate the link performance should give you a good indication of what you can expect from the radio kit

No, thats new on me! thanks looks interesting. trees are my biggest concern, do you have much experience with this? There is not much tree cover, but what there is lies about 100mtrs away from the receiver - I imagine the software cannot account for this

 

[UNG]

No, thats new on me! thanks looks interesting. trees are my biggest concern, do you have much experience with this? There is not much tree cover, but what there is lies about 100mtrs away from the receiver - I imagine the software cannot account for this

You need a good point to point line of sight as mentioned earlier fresel incursion which could be trees, buildings, masts / pylons can compromise data throughput as can heavy rain. I have not actually looked at the software I linked to but most software for radio calcs can take account of expected regional rainfall.
When I was involved in installing data radio equipment with frequencies from 2.4 to 60GHz and antenna sizes ranging from 100mm square flat plates to 2.4M diameter dishes in the UK & Europe the company I subbed for had path profiling software that took account of earth curvature, ground profile, woodland and even man made objects it linked to OS maps and was expensive although it was no substitute for the human eyeball and a physical survey the desktop exercise just prevented the traveling to look at jobs that had no chance of working although some customers would pay for 3 or more radio links to get around obstructions to provide 1 data link between sites

 

[UNG]

Do you have any pictures of your proposed link path it might make it easier to offer advice on how things may affect what you are intending to do

 

[SpecialistEnergy]

Do you have any pictures of your proposed link path it might make it easier to offer advice on how things may affect what you are intending to do

attached a pic from the online tool - the only issue is trees 200 mrs away from one of the mast points

 

[UNG]

Can't see much problem with that link and I don't think the trees at 200M will cause you any problems.
The good thing with path profile software is you have RX values to aim for and it validates that you have the antennas correctly aligned when you are setting the link up, even fractions of a degree can make a massive difference for the reliability of a link

 

[SpecialistEnergy]

Thanks @UNG

 

[static zap]

Can't see much problem with that link....

Cheers UNG ...

Unless you live in a valley the RAF , or local light aircraft frequent .
It looks nice .
(was amazed how signals will take the long route across water ,)
( just to suprise you )
If it is a valley is it often mist filled ?

 

[UNG]

Cheers UNG ...

Unless you live in a valley the RAF , or local light aircraft frequent .
It looks nice .
(was amazed how signals will take the long route across water ,)
( just to suprise you )
If it is a valley is it often mist filled ?

That is why the bigger links over water use space diverse antennas. There are many things that affect and attenuate radio waves there is even a difference from day to night. With regard to aircraft they are not normally in the radio path for any significant time although I believe the weapons radar on apache helicopters can affect 5.8GHz radio links
One of the best tales I was told by a radio engineer I worked with was a radio link he installed kept frequently dropping out for months until it stopped working completely he went to investigate and found the line of sight had changed because a new bridge had been built right across the link path

 

[SpecialistEnergy]

Ha - some things you cannot plan for...