This is a discussion on rq-170 video decoded and shown off by iran within the Air Force & Aviation forum, part of the Global Defense & Military category; Appreciate the lesson in communications Looks like my 12 years in Defence communications and Cryptography was for naught
When is ...
It would appear that you missed (or perhaps misunderstood) a few things. For a UAV like the RQ-170, it would seem that the comms to & from the UAV is handled via SATCOM datalinks. If one looks at a few photos of the 'Beast of Kandahar' it would appear that there are some bumps/domes on the top of the wing which could house a skyward pointed satellite dish. By the very nature of a dish antennae, they are directional. While RF emissions from an aircraft-mounted satellite dish are detectable, the detecting antennae would need to be positioned between the transmitting aircraft and receiving satellite. In otherwords, unless Iran had a properly kitted out ELINT/ISR aircraft flying nearby the RQ-170 and at a higher altitude, Iran would not have been able to detect the transmissions from the RQ-170.
Now satellites also use dish antennaes when transmitting, which means these transmissions are also directional. It would be possible for an ESM system to detect RF emissions from the satellite (depending on how tightly the focus of the dish/RF beam was) but that would not provide much of a clue as to where the receiving UAV was located in flight.
Ah. That was a bit of an oversight on my part. Satellite guidance... It's a bit embarrassing since I kinda work with satellite guidance for a living
But yes, a Satellite guidance system does make things more complicated since, even if you are able to detect there is such radiation in the area, you won't be able to get a bearing.
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Also potentially complicating the detection of RF emissions is the use of frequency-hopping and burst transmissions.
As for disrupting the comms between a UAV like an RQ-170 and a milsat, it might be possible for a hostile ground-based or airborne emitter to do so, but I am disinclined to discuss how on an open forum.
-Cheers
Freq hopping helps to a point. In the standard radio band (2.4 GHz) there are only 6,000,000 possible combinations which for today's computer power is little. This is assuming of course they managed to get a lock on the signal.
As for the second paragraph, you sparked my curiosity. I'll have some thinking to do to see if I can come up with something.
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Originally Posted by Gremlin29
I can't argue what ifs. What I can argue is whether or not there is a recognized existing threat (there isn't). I agree it would be unwise to underestimate the Iranians however it seems somewhat humorous (to me at least) that the Iranians could get something this complex going when the Russians (or anybody else for that matter) didn't/couldn't.
Well, I was just trying to show that theoretically, the concept is simple. It was not meant as a "what if", it was meant as a possibility that appeared to be overlooked. And, if I stumbled across such discovery, I'd also keep quiet about it.
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Originally Posted by aussienscale
Appreciate the lesson in communications Looks like my 12 years in Defence communications and Cryptography was for naught
When is comes to systems like this, if you can't find it in a Google search in the public domain, you are not going to get an answer here
Cheers
lol. Sorry if I came off a bit arrogant. Not my intention. Well, I'm sure you have much more info on the practicality of this subject. I was merely going for the theory and possible solutions.
I already learned a lot from this small discussion. Thanks for the time spent educating me. I hope some day I can repay the favour (doesn't seem likely in the near future).
For the topic at hand, I recently watched the PBS show "NOVA" which had a good episode on UAVs. In it they stated that UAVs are 3x as likely to crash than regular planes. So, it gives further strength to the claim that Iran had nothing to do with the UAV going down and are indeed very, very lucky to get their hands on a shiny new toy.
Were they able to crack it? It can't be said with so little info. If they released some high res footage or some in depth sensor specifications (as in what kind of cameras and wavelengths does this UAV operate) that would be a better indication that they indeed cracked it. Of course they might just be keeping all the other info to themselves...
Ah. That was a bit of an oversight on my part. Satellite guidance... It's a bit embarrassing since I kinda work with satellite guidance for a living
But yes, a Satellite guidance system does make things more complicated since, even if you are able to detect there is such radiation in the area, you won't be able to get a bearing.
I was not talking about satellite guidance (like GPS) for UAV's, I was actually referring to the communications link between the UAV and the ground-based controler/pilot. Given that most of these (at least for the major UAV's) seem to be run from ground stations located in the US, satellites relay the data and commands back and forth between the two.
-Cheers
________________
"I'm doing the same thing I do every night, Pinky..." comment from one lab mouse to another.
I was not talking about satellite guidance (like GPS) for UAV's, I was actually referring to the communications link between the UAV and the ground-based controler/pilot. Given that most of these (at least for the major UAV's) seem to be run from ground stations located in the US, satellites relay the data and commands back and forth between the two.
-Cheers
I understood that. My comment about oversight was more directed to the general ability to use space assets to relay communications which is the obvious choice to control these assets when pitted against a small power.
Also, it appears I can't see smilies on Posts. Unless I'm using the full reply mode. Tried fiddling with my character encoding settings to no avail.
I understood that. My comment about oversight was more directed to the general ability to use space assets to relay communications which is the obvious choice to control these assets when pitted against a small power.
Also, it appears I can't see smilies on Posts. Unless I'm using the full reply mode. Tried fiddling with my character encoding settings to no avail.
AFAIK the use of SATCOMS has little to do with the 'scale' of the opponent, but rather much more to do with here the control centres are located. In this case, the major US UAV control centres are located within the continental US, which means that long distance comms is either via satellite or bouncing RF signals off the ionosphere. Given some of the inherent limitations associated with using the ionosphere, satellites just make much more sense.
-Cheers
________________
"I'm doing the same thing I do every night, Pinky..." comment from one lab mouse to another.
AFAIK the use of SATCOMS has little to do with the 'scale' of the opponent, but rather much more to do with here the control centres are located. In this case, the major US UAV control centres are located within the continental US, which means that long distance comms is either via satellite or bouncing RF signals off the ionosphere. Given some of the inherent limitations associated with using the ionosphere, satellites just make much more sense.
-Cheers
Well, I just said small power since vs a large power I assume that the first things going down is all manner of satellites.
Ionosphere bouncing is actually what I was thinking to detect Satellite transmissions
Well, I just said small power since vs a large power I assume that the first things going down is all manner of satellites.
Ionosphere bouncing is actually what I was thinking to detect Satellite transmissions
The problem (or rather one of the major problems) with relying on ionosphere backscatter to detect transmissions to a satellite, is the fact that frequencies most commonly used to communicate with a satellite are higher than the frequencies usually used when bouncing a signal off the ionosphere.
In order for the signal to exit the atmosphere and actually reach the satellite, it needs to punch through the ionosphere. Also the RF reflecting properties of the ionosphere change depending on the local time of day.
-Cheers
________________
"I'm doing the same thing I do every night, Pinky..." comment from one lab mouse to another.
The problem (or rather one of the major problems) with relying on ionosphere backscatter to detect transmissions to a satellite, is the fact that frequencies most commonly used to communicate with a satellite are higher than the frequencies usually used when bouncing a signal off the ionosphere.
In order for the signal to exit the atmosphere and actually reach the satellite, it needs to punch through the ionosphere. Also the RF reflecting properties of the ionosphere change depending on the local time of day.
-Cheers
Yeah, was reaching that conclusion since it had to be a frequency that would both be reflective on the Ionosphere and be able to interfere with a Satellite signal that goes through the said ionosphere. It's not an easy problem to solve with satellite based transmissions... USA should be show a bit more sportsmanship... where's the fun this way?
Seriously though, interesting problem. I might just nag my former EM teacher for a clue or three
Yeah, was reaching that conclusion since it had to be a frequency that would both be reflective on the Ionosphere and be able to interfere with a Satellite signal that goes through the said ionosphere. It's not an easy problem to solve with satellite based transmissions... USA should be show a bit more sportsmanship... where's the fun this way?
Seriously though, interesting problem. I might just nag my former EM teacher for a clue or three
even if they were using the same freq it still wouldn't work
you can't do 3D track management with ionospheric systems
your teacher should know that already
________________ A corollary of Finagle's Law, similar to Occam's Razor, says:
"Never attribute to malice that which can be adequately explained by stupidity"
Well, you can using signal modulation. It's simply a matter of knowing the speed of travel and the rate at which frequency is increased. You know the distance the signal has to cover and you can compare (by correlation for example) the signal you should receive and the signal you did receive. That way, through the equation of modulation (like f = f0+k.t, where t is time and k is frequency increase rate) you know at which time in the flight path the signal interacted with the beam. You'll know the vertical data using the time the signal got intercepted to calculate the total flight path and, since you know X and Y, you're able to extract Z. The problem however is when you take into account the fact that you're trying to detect something going through the ionosphere, with something that doesn't go through the ionosphere... Not to mention the fact mentioned by Todjaeger that ionosphere is not constant during the day though I left that problem further on because first I need to think of a way to have a frequency that does both these things... Athmospherec correction is achieved in the visible spectrum with active optics and a laser star... Radio however is another matter. But probably having a secondary station measuring ionosphere response coupled through a graphene tube to provide maximum speed of transmission... but that drifts from the issue since Iran has no capabilities of building graphene. The purpose of this exercise to me is to see how easy a theory can be formulated and if it is indeed feasible for a nation like Iran to pursue it. That involves lower tech assets and ability to test such intelligence.
Well, you can using signal modulation. It's simply a matter of knowing the speed of travel and the rate at which frequency is increased. You know the distance the signal has to cover and you can compare (by correlation for example) the signal you should receive and the signal you did receive. That way, through the equation of modulation (like f = f0+k.t, where t is time and k is frequency increase rate) you know at which time in the flight path the signal interacted with the beam. You'll know the vertical data using the time the signal got intercepted to calculate the total flight path and, since you know X and Y, you're able to extract Z. The problem however is when you take into account the fact that you're trying to detect something going through the ionosphere, with something that doesn't go through the ionosphere... Not to mention the fact mentioned by Todjaeger that ionosphere is not constant during the day though I left that problem further on because first I need to think of a way to have a frequency that does both these things... Athmospherec correction is achieved in the visible spectrum with active optics and a laser star... Radio however is another matter. But probably having a secondary station measuring ionosphere response coupled through a graphene tube to provide maximum speed of transmission... but that drifts from the issue since Iran has no capabilities of building graphene. The purpose of this exercise to me is to see how easy a theory can be formulated and if it is indeed feasible for a nation like Iran to pursue it. That involves lower tech assets and ability to test such intelligence.
What you have started to describe is a OTH radar array. Such systems do already exist, typically using HF radio bouncing off the ionosphere. Australia has several such systems (JORN, SECAR, etc) involving several different emitters and even more receivers.
As GF has mentioned more than once though, such systems are 2D, not 3D.
There is more about them, but attempting to detect/track SATCOM emissions from a UAV using such an array is not viable, because the sensing arrays will not know specific pieces of information needed to determine position.
-Cheers
________________
"I'm doing the same thing I do every night, Pinky..." comment from one lab mouse to another.
Well, you can using signal modulation. It's simply a matter of knowing the speed of travel and the rate at which frequency is increased. You know the distance the signal has to cover and you can compare (by correlation for example) the signal you should receive and the signal you did receive. That way, through the equation of modulation (like f = f0+k.t, where t is time and k is frequency increase rate) you know at which time in the flight path the signal interacted with the beam. You'll know the vertical data using the time the signal got intercepted to calculate the total flight path and, since you know X and Y, you're able to extract Z. The problem however is when you take into account the fact that you're trying to detect something going through the ionosphere, with something that doesn't go through the ionosphere... Not to mention the fact mentioned by Todjaeger that ionosphere is not constant during the day though I left that problem further on because first I need to think of a way to have a frequency that does both these things... Athmospherec correction is achieved in the visible spectrum with active optics and a laser star... Radio however is another matter. But probably having a secondary station measuring ionosphere response coupled through a graphene tube to provide maximum speed of transmission... but that drifts from the issue since Iran has no capabilities of building graphene. The purpose of this exercise to me is to see how easy a theory can be formulated and if it is indeed feasible for a nation like Iran to pursue it. That involves lower tech assets and ability to test such intelligence.
and has been repeatedly explained to you, you cannot. Signal modulation will not work because of the nature of the tech involved, repeatedly stating it will work ignores the reality of what developments have been conducted by countries such as the US, France, Australia and Russia - ie the leading tech proponents of bi-static/backscatter solutions
please don't present opinions as technical solutions, there are a whole pile of tech experts on here who can refute but are going to be disinclined to discuss in detail on a public forum anyway
but, perhaps you are aware that the US and Australia are currently involved in enhancing track management for such systems, but it cannot be done on a single system
you are starting to push the boundaries of tolerance so I suggest that you find a way to present your responses, but arguing at a technical level when you clearly are not aware of the limitations already is not helping your credibility - esp when you imply that you have a teacher who can help you out - if he doesn't know this already then he needs to find another career as if he is giving you advice he obviously has no clue at all
none of the above theory works in reality - and there's close to 30 years of real world exp by the russians, americans, french, australians to back it up - if he doesn't understand it by now then I wonder what the hell he is teaching kids. he's no EM/Signature/Signals/RF expert - that's for sure.
in addition, as also stated prev, the Iranians have NONE of the infrastructure in place to actually try it on anyway.
there are only 6 countries in the world that have those basics in place. Iran isn't one of them
re the issue about discussing the theory on possibilities, perhaps thats why the US and Australia decided to arrange a formal agreement to transfer and develop technology to cross those boundaries - NONE of the detail will end up being discussed seriously in an open public forum
________________ A corollary of Finagle's Law, similar to Occam's Razor, says:
"Never attribute to malice that which can be adequately explained by stupidity"
and has been repeatedly explained to you, you cannot. Signal modulation will not work because of the nature of the tech involved, repeatedly stating it will work ignores the reality of what developments have been conducted by countries such as the US, France, Australia and Russia - ie the leading tech proponents of bi-static/backscatter solutions
please don't present opinions as technical solutions, there are a whole pile of tech experts on here who can refute but are going to be disinclined to discuss in detail on a public forum anyway
but, perhaps you are aware that the US and Australia are currently involved in enhancing track management for such systems, but it cannot be done on a single system
you are starting to push the boundaries of tolerance so I suggest that you find a way to present your responses, but arguing at a technical level when you clearly are not aware of the limitations already is not helping your credibility - esp when you imply that you have a teacher who can help you out - if he doesn't know this already then he needs to find another career as if he is giving you advice he obviously has no clue at all
none of the above theory works in reality - and there's close to 30 years of real world exp by the russians, americans, french, australians to back it up - if he doiesn't understand it by now then I wonder what the hell he is teaching kids. he's no EM/Signature/Signals/RF expert - that's for suyre.
in addition, as also stated prev, the Iranians have NONE of the infrastructure in place to actually try it on anyway.
there's only 6 countries in the world that have those basics in place. Iran isn't one of them
re the issue about discussing the theory on possibilities, perhaps thats why the US and AUstralia decided to arrange a formal agreement to transfer and develop technology to cross those boundaries - NONE of the detail will end up being discussed seriously in an open public forum
Again, I'm talking from a purely theoretical point of view. I'm sorry if I overstepped. Not my intention.
I was told they don't work to detect 3D and I believe you. I was just thinking of theory. I never said that those systems were built. It's something I like to do. To build hypothetical scenarios and try to evaluate their feasibility. It's a hobby. I was aware of bystatic Radars but I wasn't aware that pulse modulation was already used and i never suggested using just one transmitter receiver to do so. It shouldn't have come off that way.
I never got around to talk to my former teacher as i didn't happen to run into him. However, he is a theoretical physicist so that's always in the theory realm. I don't pretend that me or him know more about the technicalities of build such a system then anyone who is a pro in the area. Theory however is ahead of practice however and another matter all together.
I'll stop arguing this subject as per your request and will develop my brain teasers in peace and quiet
Again, I'm talking from a purely theoretical point of view. I'm sorry if I overstepped. Not my intention.
I was told they don't work to detect 3D and I believe you. I was just thinking of theory. I never said that those systems were built. It's something I like to do. To build hypothetical scenarios and try to evaluate their feasibility. It's a hobby. I was aware of bystatic Radars but I wasn't aware that pulse modulation was already used and i never suggested using just one transmitter receiver to do so. It shouldn't have come off that way.
I never got around to talk to my former teacher as i didn't happen to run into him. However, he is a theoretical physicist so that's always in the theory realm. I don't pretend that me or him know more about the technicalities of build such a system then anyone who is a pro in the area. Theory however is ahead of practice however and another matter all together.
I'll stop arguing this subject as per your request and will develop my brain teasers in peace and quiet
I don't have a problem at all with debating technical issues (within the opsec constraints of what can be discussed in an open forum) , but it was the way it was coming across, that may be one of the frailties of debating across the internet when intent and tone are not easy to always determine
by all means discuss, but it might be worth your while to check your package before you post just in case it can come across adversely
________________ A corollary of Finagle's Law, similar to Occam's Razor, says:
"Never attribute to malice that which can be adequately explained by stupidity"
Looks like my 12 years in Defence communications and Cryptography was for naught 
