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UK 2.4Ghz Frequency site scan prior to flight

Joined
Jun 18, 2015
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Location
South West UK
Website
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Hello fellow members

(I'm not sure if this has been covered already)

I have been commissioned to get some aerial shots over a very large nuclear construction site in the UK, this for me is an unusual request so I am wondering if anyone has any solutions to the message below?

Many thank in advance


"Can you identify how you will monitor the 2.4GHz frequency band over the entire flight path prior to flight?


As stated previously, this frequency band is the general WiFi band used by the managed Internet Service on site, a number of wireless links, and more importantly can be transmitted from mobile phones if set up as a WiFi hotspot. The latter is almost impossible to police or predict.

I would strongly recommend that a frequency band dedicated to these sort of operations should be used. 900MHz is one such example."
 
Hello fellow members

(I'm not sure if this has been covered already)

I have been commissioned to get some aerial shots over a very large nuclear construction site in the UK, this for me is an unusual request so I am wondering if anyone has any solutions to the message below?

Many thank in advance


"Can you identify how you will monitor the 2.4GHz frequency band over the entire flight path prior to flight?


As stated previously, this frequency band is the general WiFi band used by the managed Internet Service on site, a number of wireless links, and more importantly can be transmitted from mobile phones if set up as a WiFi hotspot. The latter is almost impossible to police or predict.

I would strongly recommend that a frequency band dedicated to these sort of operations should be used. 900MHz is one such example."
I would answer as follows:
'Dear Sirs,
Thank you for your communication but could you please put me in contact with someone within your organization who actually understands frequency allocation spectrums within the UK and doesn't try and suggest I use an illegal frequency band for RC flight/telemetry purposes?

Yours sincerely '

OK, I jest (or do I) but this is a classic case of a little bit of knowledge is a dangerous thing and whoever wrote that email/letter to you clearly does not have a clue what they are talking about.
One, they are suggesting 900mhz which is for ground based communication/GSM network so it would be illegal for you to operate within those frequencies in the UK.
Second, why are they worrying about a locked 2.4ghz link which has frequency hopping capability in the event of crowded channels? The data link is also enhanced using packet technology that is parity checked for integrity. In years of operation on 2.4ghz RC equipment from manufactures like Futaba, Spektrum and Jeti as well as more lately with DJI, I have never suffered any problems in any 'wi-fi' environment.
Even if you lost all communication with your aircraft, fail safe would kick in and the flight controller would initiate RTH to bring the UAV safely back.
I find their communication ill informed.

I would suggest (and point out) that what they are suggesting is actually illegal in the UK and also the equipment you use has safeguards built in that in the event of loss of control link it will return to its take off point.

You would need to to an extensive Site inspection and risk survey and to shut them up I would identify two or more possible ditch sites for emergency purposes.

Since they have already demonstrated they are clueless, you could further apease them by saying you have a frequency monitor built into your equipment and you will undertake channels scans both prior and during flight. (Which is easy enough to do by just flipping into the screen with DJI Go and taking a look at how busy the channels are).
If you wanted belt and braces you could always purchase a portable spectrum analyzer and charge them for it in your fee. Then you could whip out your posh new toy and explain you are doing a spectrum scan of the area - all Star Trek like and they will all nod at each other in approval and awe but none of them will have a clue what you are doing. :p
 
ps. I previously did a job at the same site last April with a very detailed risk assessment that bounced back a few times for tweaking, they did mention to another source since then that another UAV provider lost control of their drone and crashed into a crane. no one was injured.
 
ps. I previously did a job at the same site last April with a very detailed risk assessment that bounced back a few times for tweaking, they did mention to another source since then that another UAV provider lost control of their drone and crashed into a crane. no one was injured.
What about the poor crane? :eek:.
Ahh.....that's probably why they are all nervous and jittery and trying to get all technical.
Would be interesting to know what platform the other provider was flying at the time of incident.
 
I would answer as follows:
'Dear Sirs,
Thank you for your communication but could you please put me in contact with someone within your organization who actually understands frequency allocation spectrums within the UK and doesn't try and suggest I use an illegal frequency band for RC flight/telemetry purposes?

Yours sincerely '

OK, I jest (or do I) but this is a classic case of a little bit of knowledge is a dangerous thing and whoever wrote that email/letter to you clearly does not have a clue what they are talking about.
One, they are suggesting 900mhz which is for ground based communication/GSM network so it would be illegal for you to operate within those frequencies in the UK.
Second, why are they worrying about a locked 2.4ghz link which has frequency hopping capability in the event of crowded channels? The data link is also enhanced using packet technology that is parity checked for integrity. In years of operation on 2.4ghz RC equipment from manufactures like Futaba, Spektrum and Jeti as well as more lately with DJI, I have never suffered any problems in any 'wi-fi' environment.
Even if you lost all communication with your aircraft, fail safe would kick in and the flight controller would initiate RTH to bring the UAV safely back.
I find their communication ill informed.

I would suggest (and point out) that what they are suggesting is actually illegal in the UK and also the equipment you use has safeguards built in that in the event of loss of control link it will return to its take off point.

You would need to to an extensive Site inspection and risk survey and to shut them up I would identify two or more possible ditch sites for emergency purposes.

Since they have already demonstrated they are clueless, you could further apease them by saying you have a frequency monitor built into your equipment and you will undertake channels scans both prior and during flight. (Which is easy enough to do by just flipping into the screen with DJI Go and taking a look at how busy the channels are).
If you wanted belt and braces you could always purchase a portable spectrum analyzer and charge them for it in your fee. Then you could whip out your posh new toy and explain you are doing a spectrum scan of the area - all Star Trek like and they will all nod at each other in approval and awe but none of them will have a clue what you are doing. :p

RF Explorer — Handheld RF Spectrum Analyzer
There are some reasonably priced models here that should suit your purposes without costing too much.
 
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As you both say - I think youve hit the nail on the head - they are putting two and two together and working on the premise that you too will lose control and hit the crane so are thinking overtime for health and safety.

Also have you've found out, issues re security on a nuclear site are massive.

Depending on the level of completeness, there might be a number of signals that could interfere with your I2 (could that also be what happened to the previous one), so I would say a RF signal analyser would be a useful addition -but do you know how to read one. It could be as simple as a faulty microwave in one of the portacabins onsite for example.

At least you have the fact you've worked with them before as a good starting point! Good Luck.
 
Let's see. Crane, massive counter weights, get to close to it and watch the compass errors come up and your drone take off. Watched it happen to a p4p and he wasn't even that close to it. Even with a lot of rf traffic it would still be pressing to see it interfering with your controls, but if in doubt do like the editor says and buy a rf meter and charge it to their bill. Rf explorer 6g combo is a nice set up.
 
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I would answer as follows:
'Dear Sirs,
Thank you for your communication but could you please put me in contact with someone within your organization who actually understands frequency allocation spectrums within the UK and doesn't try and suggest I use an illegal frequency band for RC flight/telemetry purposes?

Yours sincerely '

OK, I jest (or do I) but this is a classic case of a little bit of knowledge is a dangerous thing and whoever wrote that email/letter to you clearly does not have a clue what they are talking about.
One, they are suggesting 900mhz which is for ground based communication/GSM network so it would be illegal for you to operate within those frequencies in the UK.
Second, why are they worrying about a locked 2.4ghz link which has frequency hopping capability in the event of crowded channels? The data link is also enhanced using packet technology that is parity checked for integrity. In years of operation on 2.4ghz RC equipment from manufactures like Futaba, Spektrum and Jeti as well as more lately with DJI, I have never suffered any problems in any 'wi-fi' environment.
Even if you lost all communication with your aircraft, fail safe would kick in and the flight controller would initiate RTH to bring the UAV safely back.
I find their communication ill informed.

I would suggest (and point out) that what they are suggesting is actually illegal in the UK and also the equipment you use has safeguards built in that in the event of loss of control link it will return to its take off point.

You would need to to an extensive Site inspection and risk survey and to shut them up I would identify two or more possible ditch sites for emergency purposes.

Since they have already demonstrated they are clueless, you could further apease them by saying you have a frequency monitor built into your equipment and you will undertake channels scans both prior and during flight. (Which is easy enough to do by just flipping into the screen with DJI Go and taking a look at how busy the channels are).
If you wanted belt and braces you could always purchase a portable spectrum analyzer and charge them for it in your fee. Then you could whip out your posh new toy and explain you are doing a spectrum scan of the area - all Star Trek like and they will all nod at each other in approval and awe but none of them will have a clue what you are doing. :p
Isn't the transmission channel screen only for video?
 
It's interleaved within the 2.4ghz link.
Lightbridge on the I1 uses 2.4ghz for control, telemetry and video downlink. It's all contained within the data stream.
The channel screen is an indication of how busy the band is in real time.
That's definitely good to know. Clearly DJI have got their nomenclature wrong.
 
Let's see. Crane, massive counter weights, get to close to it and watch the compass errors come up and your drone take off. Watched it happen to a p4p and he wasn't even that close to it. Even with a lot of rf traffic it would still be pressing to see it interfering with your controls, but if in doubt do like the editor says and buy a rf meter and charge it to their bill. Rf explorer 6g combo is a nice set up.
I use this one, especially in congested areas and industrial sites. That helps to make sure what kind of environment you're dealing with.
 
Interesting discussion but nobody said what u do with the Spectrum Analyzer? -6db no fly or fly, intermittent or constant interference? Since channel hopping for control is automatic, manual selection is for telemetry, there isn't much u can do about the channel u use for control. In 5 yrs of drone work, I've never had the control link disconnect.
 
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Im guessing you would use the RF unit to see which channels you should manually select or avoid. We have a 6g 5.8/ 2.4 unit wrote into our ops manual but to this date i have never had to use it.

The reality is that all the analyses can do is confirm if signals are too strong to fly and possibly point you towards the source.
 
The DJI Inspire 1 pros that I have I believe will only use the automatically selected channels for control. 5.8GHz is for the connection to the second RC to control the camera. Manual channel selection is only for telemetry. But to your other point, what is a good and bad signal. The control system is designed to ignore a few dropped signals (I believe it hangs in for 3 secs without a link before triggering RTH) so a few noise spikes shouldn't cause any problems. So my question to the radio experts is how do you use a signal analyzer? What is the go no go criteria?
 
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Yea I would write back and tell them as part of your ground safety checks you will do some onsite random band checks looking at what's going before you fly then as the Editor says periodic band checks from aircraft via built in app, also fluff it up about the failsafe and Light bridge info

This should appease them

My aircraft uses a proprietary frequency hopping and Spread Spectrum technology, it has high transmission stability and strong anti-jamming capability's using MIMO multiple antenna technology and OFDM modulation with advanced algorithms to effectively improve the stability of the system data bandwidth in complex environments.

Using Real-time monitoring of each downlink channel interference state it dynamically selects the best channel in the band dynamically helping to ensure a safe flight.
 
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Interesting discussion but nobody said what u do with the Spectrum Analyzer? -6db no fly or fly, intermittent or constant interference? Since channel hopping for control is automatic, manual selection is for telemetry, there isn't much u can do about the channel u use for control. In 5 yrs of drone work, I've never had the control link disconnect.
I have yet to have a lost link incident as well even though I operate in a very crowded bandwidth environment. I attribute my success to date on being in close proximity to the aircraft at all times (within 250 m). The greater the separation distance, the more trouble you are asking for.
 

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