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> True ECM, Flying over Radar
booklord
post Jul 6 2006, 01:20 AM
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Anyone have any thoughts on SR3 style ECM?

Not the jammer tech in SR4, but the stuff designed to "cloak" you from radar.

What sort of test would involve sneaking past a stationary radar facility? Electronic Warfare + ECM against Sensors + ECCM?

or

Vehicle + Electronic Warfare + ECM against Radar station Pilot + Sensors + ECCM?


Is Electronic warfare even appropriate since it involves messing with sensors signals and not computer signals?
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Aaron
post Jul 6 2006, 02:48 AM
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QUOTE (booklord)
Anyone have any thoughts on SR3 style ECM?

Not the jammer tech in SR4, but the stuff designed to "cloak" you from radar.

What sort of test would involve sneaking past a stationary radar facility? Electronic Warfare + ECM against Sensors + ECCM?

or

Vehicle + Electronic Warfare + ECM against Radar station Pilot + Sensors + ECCM?


Is Electronic warfare even appropriate since it involves messing with sensors signals and not computer signals?

No reason not to treat it the same. Radar and wifi use the same medium, just on different wavelengths (frequencies).
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Cynic project
post Jul 6 2006, 03:08 AM
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In 3ed they had sepret rules for rigger chanels..THey said that unles syou were using rigger gear you couldn't break the codes..IR they made up bulleshit radio rules cause they could...
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nezumi
post Jul 6 2006, 01:53 PM
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I believe ECM only keeps you from getting an active sensor lock because it fills the air with noise. It doesn't help you sneak by anything, any more than sending a parade down the street helps you drive your motorcycle behind it unnoticed.

ECD might be a little better. I'd look at that for getting past radar. If this is a flying object, I'd also give bonuses for increasing range and keeping close to the ground. But basically, your best bet is paying for technology that increases your Signature rating, not stuff that jams sensors.
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ornot
post Jul 6 2006, 02:25 PM
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I wouldn't call that the greatest analogy, as observers might be more interested in the parade than the motorcycle, especially if the parade has jugglers! :silly:

I do get your point that you're still making people look in the street so they realise there's something there, when ideally you don't want anyone to notice anything going on in the street despite it being full of you and your motorcycle.

I think you might have meant reduce signature rating, as IIRC the higher your signature the easier it is to see you.
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booklord
post Jul 6 2006, 02:59 PM
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QUOTE
I believe ECM only keeps you from getting an active sensor lock because it fills the air with noise. It doesn't help you sneak by anything, any more than sending a parade down the street helps you drive your motorcycle behind it unnoticed.


I thought it did.

Example
---------------
A Radar station 10 Kilometers away sends out a sensor signal that a sensor signal that covers a 50 Kilometer radius.

The runners vehicle is trying to sneak accross the border. It sends out a jamming signal that interferes and blocks the sensor signal.

However the signal from the jamming only has a range of a few hundred meters. So it never reaches the radar station which is 10 kilometers away.

So neither the original sensor signal which was blocked nor the jamming signal which doesn't have the range ever returns to the radar station, making it look the original sensor signal found nothing.
----------------------------

Now my thought was that a rigger who monitoring the signal frequencies using his Electronic Warfare skill would detect the sensor station's signal and adjust his ECM to compensate and use his vehicle skill or infiltration(vehicle) skill (whichever is lower) to allow him to fly close to the terrain to avoid detection.

Meanwhile the opposition would use its Electonic Warfare skill and its sensors and ECCM to try detect any intruders.

So

(vehicle(inflitration) or Vehicle skill) + Electronic Warfare + ECM
vs.
sensor rating + Electronic WArfare + ECCM

(with the possible addition that ECCM dice can only equal the ECM dice they cannot exceed them)
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nezumi
post Jul 6 2006, 03:38 PM
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QUOTE (ornot @ Jul 6 2006, 09:25 AM)
I think you might have meant reduce signature rating, as IIRC the higher your signature the easier it is to see you.

I'm speaking from an SR3 perspective. In SR3, signature is the TN you have to meet to "see" the object in question.

Booklord, let me quote from the rule book, then give the real life explanation as well:

QUOTE

Jammers come in two varieties: area jammers and spot jammers.  Area jammers broadcast over a large area (based on their Signal attribute), effectively blanketing out all wireless nodes in that area....  Any device with a Signal rating less than the jamming device's Signal rating is overwhelmed.
(p. 225)

1. It seems fairly clear that jammers (ECM) can only work on sensors within their range.
2. Jammers work by overwhelming devices of a lower signal rating.
3. If a device (like our huge radar tower) has a higher signal rating, it will not be jammed.

So unless your ECM gear has a higher rating than the sensor array, it's a moot point.

In real life, as I said, ECM works by filling the radio waves with spam. The radio tower WILL notice this. If it doesn't, the ECM isn't working. However hopefully the signature of the vehicle won't be noticed amid all the trash.

QUOTE
It sends out a jamming signal that interferes and blocks the sensor signal.


I'd love to hear how you think a radio signal can "block" another signal. This really isn't possible. The best you can do is give an artificial echo, so the radar tower gets two echos from the same signal, creating 'ghosts'. Anything else done to block the signal would have to involve physical measures like radar absorbing paint or a sleek design.

QUOTE
However the signal from the jamming only has a range of a few hundred meters. So it never reaches the radar station which is 10 kilometers away.


This would fly in the face of logic, since it becomes beneficial to have a low level ECM unit, as higher levels would be detected. Remember, the ECM doesn't work on the radio waves, it works on the initial sensor array. If the array isn't within range of the ECM, the ECM has no effect.
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Austere Emancipa...
post Jul 6 2006, 04:06 PM
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QUOTE (nezumi)
In real life, as I said, ECM works by filling the radio waves with spam. The radio tower WILL notice this. If it doesn't, the ECM isn't working.

This is exactly right, as anyone who has played a modern flight sim should know.
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booklord
post Jul 6 2006, 04:09 PM
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QUOTE
1. It seems fairly clear that jammers (ECM) can only work on sensors within their range.
2. Jammers work by overwhelming devices of a lower signal rating.
3. If a device (like our huge radar tower) has a higher signal rating, it will not be jammed.

On this I agree, the jammer tech described in SR4 is not ECM. Or at the very least it's ECM at its most rudimentary form. I thought that ECM in SR3 was far more advanced.

QUOTE
So unless your ECM gear has a higher rating than the sensor array, it's a moot point.

In real life, as I said, ECM works by filling the radio waves with spam. The radio tower WILL notice this. If it doesn't, the ECM isn't working. However hopefully the signature of the vehicle won't be noticed amid all the trash.

Unless of course your ECM has greater signal strength and less range. Or the ECM signal is capable of disrupting the sensor signal by sending out a signal that messes with its wavelength or frequency.

QUOTE
I'd love to hear how you think a radio signal can "block" another signal. This really isn't possible. The best you can do is give an artificial echo, so the radar tower gets two echos from the same signal, creating 'ghosts'. Anything else done to block the signal would have to involve physical measures like radar absorbing paint or a sleek design.

Be careful bringing RL physics into this! I always thought that ECM in SR3 was a technological advancement that we simply don't have today. However in the electronic warfare section of the SR4 book it does say that a runner may:
1) Detect a hidden node
2) Decrypt its signal
3) intercept the signal
and finally
4) edit the signal
If you can do that with a comm signal then you can almost certainly interfere with sensor signals can't you?

QUOTE
This would fly in the face of logic, since it becomes beneficial to have a low level ECM unit, as higher levels would be detected. Remember, the ECM doesn't work on the radio waves, it works on the initial sensor array. If the array isn't within range of the ECM, the ECM has no effect.

Can't you match its wavelength or frequency or something along those lines? Take for example the concept of a "white noise" generator. It disrupts the frequencies that sound travels on and therefore blocks noise within its area of effect. But doesn't overpower them.

QUOTE
This is exactly right, as anyone who has played a modern flight sim should know.

But this isn't a modern flight simulator. It's the future some 65 years from now.
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Austere Emancipa...
post Jul 6 2006, 04:35 PM
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QUOTE (booklord)
I thought that ECM in SR3 was far more advanced.

It isn't. It still requires the affected sensor to be within the range of the ECM system -- it in fact works about exactly like modern, RL ECM systems. Which, considering SR3s track record with vehicles, is quite astonishing really.

QUOTE (booklord)
I always thought that ECM in SR3 was a technological advancement that we simply don't have today.

It isn't. There's absolutely nothing special about SR3 ECM.

QUOTE (booklord)
But this isn't a modern flight simulator. It's the future some 65 years from now.

Too bad so much of the technology is behind current developments, then, eh? If you want futuretech, use ED (and ECD), which is much closer to what you're going for -- but still requires you to be able to reach the sensor you intend to fool.
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booklord
post Jul 6 2006, 05:26 PM
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Okay then let's set up the scenario.....

A group of runners need to smuggle something over the border. They're facing multiple radar stations. I'd like to reduce it to a opposed test roll.


Now the book says to sneak past sensors is

(vehicle or infiltration[lower one]) + Reaction
vs
(pilot or autosoft[higher one]) + Sensor ( modified by signature)

But I don't think that reaction is appropriate for this kind of a test. It isn't a situation where overhead drones are scanning for you and you need to drive behind a corner. It's a situation where you're constantly trying to avoid detection for the better part of an hour as you travel from point A to point B.

What do you think is a proper opposed die test?
What role should ECM or ECCM play in such a test?
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Lagomorph
post Jul 6 2006, 05:29 PM
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I'd say, make it an extended (infiltration|vehicle) + reaction test, with a threshold = the higest amount of dice available at any one tower.
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booklord
post Jul 6 2006, 05:42 PM
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QUOTE
I'd say, make it an extended (infiltration|vehicle) + reaction test, with a threshold = the higest amount of dice available at any one tower.


But what does reaction have to do with it? I can see reaction in smaller scale tests, but I just don't see how it applies here.

I'm also unsure on the extended test bit. Generally extended tests deal with how long it takes to perform a certain task. Success is often just a matter of time and avoiding glitches. But success in this case is hardly guaranteed.
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nezumi
post Jul 6 2006, 06:42 PM
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I hope you've been set clear in regards to the original use of ECM. The one thing I still have to comment on:

QUOTE
Can't you match its wavelength or frequency or something along those lines? Take for example the concept of a "white noise" generator. It disrupts the frequencies that sound travels on and therefore blocks noise within its area of effect. But doesn't overpower them.


It is possible with noise (I'm not sure about radio waves) to sync up the waves with their precise opposite resulting in no noise. However, the amount of precision required is astonishing, so it really isn't feasible in any way if used on a flying platform against multiple targets and no advanced knowledge of what the pattern will look like exactly. So no, ECM doesn't do this. And no, a white noise generator doesn't work like this either. A white noise generator works pretty much exactly like ECM. Remember that a mic is vulnerable to a wider range of sound than our ears. So the white noise generator just fills the air with random air waves which cause such vibration on the mic that the audible stuff is overridden. It's exactly the same concept as ECM, it works by overriding it.

Reaction has a lot to do with this. Remember what I said about keeping close to the tree line? If you are within fifty feet of the tree line, your signature will be overridden by that of the terrain. If you're closer to 10 feet, you'll be practically invisible to radar. Of course, the treeline moves up and down (being full of trees), which means you'd better be a dang good pilot to be able to fly like that. This also has to do with precisely angling your aircraft so you present the smallest signature possible. The F-117 is more vulnerable to radar from the sides or rear than from the front, for instance.

Of course, the rule here is a gross simplification, and I'd throw it out. I'd require the pilot to determine how risky he's playing it. The closer he sticks to the tree line, the higher the TN (threshold, sorry) to avoid crashing, but the better cover he gets. Of course, an aircraft made for low speed, high maneuverability flying, sort of like the old Intruder jets in the Navy, or presumably a t-bird, will be easier to guide along like this than something fat and fast.

Your runners may also want to consider putting down, trekking over to the radar station, and putting it out of commission somehow until they can get the jet by. That is why you have deckers, after all.
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Austere Emancipa...
post Jul 6 2006, 06:52 PM
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QUOTE (nezumi)
It is possible with noise (I'm not sure about radio waves) to sync up the waves with their precise opposite resulting in no noise. However, the amount of precision required is astonishing, so it really isn't feasible in any way if used on a flying platform against multiple targets and no advanced knowledge of what the pattern will look like exactly.

It is apparently theoretically possible against radar (look up active radar cancellation), but it is indeed incredibly difficult and more likely to increase radar signature than decrease it under most circumstances.
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booklord
post Jul 6 2006, 07:17 PM
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But wouldn't Electronic Warfare have some role? For example the Salish know that smugglers like to use a certain valley. So they put a sensor station there. Any good smuggler would be "listening" for the station right?

How about if the station does get a sensor lock on you. Can't you use ECM to try to shake it?

QUOTE
Your runners may also want to consider putting down, trekking over to the radar station, and putting it out of commission somehow until they can get the jet by. That is why you have deckers, after all.

Probably safer just to take your chances with the border patrol then mess with a military installation. The hacker can have loads of fun dealing with the drones.
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nezumi
post Jul 6 2006, 07:44 PM
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QUOTE (booklord)
But wouldn't Electronic Warfare have some role? For example the Salish know that smugglers like to use a certain valley. So they put a sensor station there. Any good smuggler would be "listening" for the station right?

A ship with a reasonable sensor suite should be able to detect stray radio waves before they're acquired as a target by the radar tower. A sensor test with thresholds based on how far out of range of the radar tower you are, modified by environmental factors may be appropriate. In my game, I generally run on the assumption that using radar makes it pretty obvious to everyone with the appropriate level of sensors that someone in the area is using radar. Lidar isn't quite so kind. However because radar is better for sweeping an area, it's safe to assume our radar tower will use it, and so our smuggler will likely know in advance there's a tower in the area (assuming he's trying to sniff out such things and isn't moving a kajillion miles an hour, and barring environmental factors. Sticking close to the tree line works both ways, so our smuggler could come over a ridge and be very surprised to see a radar tower sitting there waiting.)

QUOTE
How about if the station does get a sensor lock on you. Can't you use ECM to try to shake it?


Yes. That's what ECM is for, when the other guy already knows you're in the area and is just trying to get a lock on you (for indentification or engaging weapons).

As for actually visiting the tower in person... Hopefully they aren't stupid enough to go in shooting. There are plenty of other ways to temporarily jam a radar tower without the users ever being aware you're doing it.
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