Noise jamming for DECM sets (Was: Automatic evasion)

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tiag
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Noise jamming for DECM sets (Was: Automatic evasion)

Post by tiag »

Automatic evasion is pure "gaming" thing that CMO/CMANO decided to implement to overcome several abstractions.
For example, regarding to SAMs but also missiles exchange in general, the use of jamming via ECM pod (Defensive jamming like ALQ-119 etc, not from Growlers, Prowlers etc) is only calculated when the missile hits you. This is an abstraction of the model. Fair enough from the initial modelling point of view. HOWEVER:
In reality, jamming pods are used to jam/block/deceive the tracking/lock, avoiding this way potentially the shot. But in CMO, I wil go defensive, because the shot was fired which puts me again under defensive when another shot is fired. And so on...
Another typical example is the outcome of BVR combat with SARH missiles combined with automatic evasion. In reality, the acft with the strongest/correct JAM signal would not allow the enemy to fire at him. In CMO, that does not happen, the acft with the longest range missile fires first, and you will get defensive by the auto evasion, loosing your lock. Outcomes in CMO and real tactics are completely orthogonal in that sense. I sincerelly doubt that this abstraction was really evaluated vs real world less coarse modells.

The real problem is the abstraction of ECM pods together with "gaming" auto evasion leads to complete non-real outcomes.
thewood1
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RE: Automatic evasion

Post by thewood1 »

I tend to agree with the above that the issue seems to be a mix of detailed simulation with broad abstraction. This is something I have worried about ever since things like trying to account for pilot visibility details in each aircraft. Whenever you start to bring in very detailed factors into an abstracted outcome, you get these weird looking results that might not match expectation when are detailed certain parameters and abstracting other. I'm worried we are past that balance of only looking at the high influence factors that significantly impact outcomes and abstracting factors that don't have that much influence. Its leading down a spiral that can't be resolved in a game that is focusing on broader issues. You end up literally building an equivalent of DCS in a game that can't support that scale.
tiag
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RE: Automatic evasion

Post by tiag »

Agree with you too.
The problem is indeed more general. What CMO faces is a well known problem in multi-resolution combat simulations: How one make modelling with different resolution interact. If my airplane "flies" in a 3D space, then it maneuvers as the real one or is it abstracted? In CMO, sometimes it abstracts, sometimes it maneuvers (=auto evasion). If my ECM pod jams, when it JAMs? At impact or before? If my A-10 is abstracted flying fully loaded at 36000ft (!), should I abstract the maximum altitude of SAMs or keep it real? IN CMO, the maximum altitude of a SAM is real, but acft can fly completely abstracted (even outside of the real flight envelope). The list goes on.
Modelling requires often abstraction in physics, chemistry, biology as well as in combat modelling, but one always need to check how these abstractions influence the result.

slimatwar
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RE: Automatic evasion

Post by slimatwar »

Another issue is that when a SAM is in the air every aircraft goes to defensive mode even if it is 100% certain that the missile isn't going towards the unit.
Dimitris
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RE: Automatic evasion

Post by Dimitris »

ORIGINAL: slimatwar
Another issue is that when a SAM is in the air every aircraft goes to defensive mode even if it is 100% certain that the missile isn't going towards the unit.

That's by design; if you ask a pilot he'll tell you that until positively proven otherwise, every missile in the air is coming right for him. Trying to be "clever" in such a case is a great way to get killed.

An easy way to break the cohesion of an enemy airgroup is to throw a missile at it, even unguided. Everyone will scatter until it becomes clear who the missile is tracking.

(There is a built-in check to determine if the missile looks like it is veering off the direction of the plane).
thewood1
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RE: Automatic evasion

Post by thewood1 »

"Combat Mission is kind of like a Van Gogh painting. If you look closely it’s just a bunch of dots that don’t make sense, and they don’t look very aesthetically pleasing but once you zoom out you start to see a cohesive picture. Once you accept the jank, it only gets better."

Coincidently, a comment on the Combat Mission forums today that I thought was cool. You can substitute CMO for Combat mission.

https://community.battlefront.com/topic ... nt=1901995

Dimitris
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RE: Automatic evasion

Post by Dimitris »

ORIGINAL: tiag
Automatic evasion is pure "gaming" thing that CMO/CMANO decided to implement to overcome several abstractions.
So real-life pilots do not manouver to avoid incoming missiles? I bet that's news to the pilots I've spoken with, at the very least.
For example, regarding to SAMs but also missiles exchange in general, the use of jamming via ECM pod (Defensive jamming like ALQ-119 etc, not from Growlers, Prowlers etc) is only calculated when the missile hits you. This is an abstraction of the model. Fair enough from the initial modelling point of view.
This is an accurate representation of how defensive ECM (deception jamming) works in the endgame phase of a missile engagement: The battle to avoid being seen and being shot at has been lost, so now the purpose is to confuse the seeker on the incoming weapon (or the remote sensor providing guidance to it) as to the precise location and movement of the defender. This involves a whole range of techniques from simple range/azimuth gate pull-off all the way to things like cross-eye jamming (an anti-AMRAAM-specific method), DRFM-driven false targets and more advanced tricks.
HOWEVER:
In reality, jamming pods are used to jam/block/deceive the tracking/lock, avoiding this way potentially the shot.
This is noise jamming, and Command handles it as an OECM function. And it is simulated, too. Many of the "why can I not launch Sparrows" questions we've had in this forum boiled down to "an enemy jammer, either onboard the target itself or at a nearby escort, was flooding my radar with static". And we also added a similar restriction even for AMRAAM-class weapons (must obtain a valid FC-grade detection prior to launch, either by radar or with another FC-grade sensor, e.g. modern IRST).

The R-27R/ER (radar variants of the AA-10) was designed with a mid-course datalink explicitly to avoid this problem. To a lesser extend this drove the design of the initial (non-Aegis) versions of the SM-2: Not needing a pre-fire lock meant that ships could shoot at incoming AV-MF formations (or cruise missiles) even in the face of ultra-powerful noise jamming from dedicated Badger-H/Js. The re-emergence of IRSTs in the West is also partially for the same reason (the other part is their counter-VLO utility).
But in CMO, I wil go defensive, because the shot was fired which puts me again under defensive when another shot is fired. And so on...
So, welcome to the shoes of the Serbian fighter pilots who faced NATO fighters over Serbia & Kosovo in 1999. You are _precisely_ describing the NATO playbook: Chuck AMRAAMs by the boatload at them, even at non-optimum range, to continously force them in the defensive and not give them a counter-shot opportunity at all (the harsh memories of the Luftwaffe MiG-29 trials were still fresh, and they prudently loathed the prospect of a WVR merge). One of the Serbian pilots dodged at least 3 AMRAAMs before he "ran out of speed, altitude, and ideas". That's life.
Another typical example is the outcome of BVR combat with SARH missiles combined with automatic evasion. In reality, the acft with the strongest/correct JAM signal would not allow the enemy to fire at him.
See above. Noise jamming preventing launch is very much a thing.
In CMO, that does not happen, the acft with the longest range missile fires first, and you will get defensive by the auto evasion, loosing your lock.
Nope. I suspect you underestimate the magnitude of the pre-fire checklist. As the saying goes, it is long and distinguished.
Outcomes in CMO and real tactics are completely orthogonal in that sense. I sincerelly doubt that this abstraction was really evaluated vs real world less coarse modells.
Nope.
The real problem is the abstraction of ECM pods together with "gaming" auto evasion leads to complete non-real outcomes.
And nope.

Peace [:)]
tiag
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RE: Automatic evasion

Post by tiag »

Hi Dimitris,

I was not really sure how to address your post above, specially the original version of it before you/someone edited part of it. Unfortunately, I got the full version of it due to the subscription of the topic. That almost put me off from trying CMO again, to be sincere to you. Anyway, let me focus on what really matters: ECM and automatic evasion in CMO.

I could try to reply each of one your points, but it would not be so helpful as a video showing my point. I think that you guys got the ECM usage by tactical aircraft (DECM pods) not correct. The usage of ECM is a great advantage to delay a tracking solution in A2A combat as well as against air defences. This is not happening in CMO. Aggregating the ECM factor, as it is now, only when the missile hits denies more capable aircraft of flying until burnthrough range and supporting their missiles (very important in SAHR vs ARH missile combat). There other problems of doing that, like ECM useage when missiles have HOJ, coverage of ECM emission during the high-G automaic evasion, etc, which I dont want to bring into discussion because I dont know how you guys are moddeling it. You know, all models are wrong, some are useful ;-).

This is the video:

On the Mechanics of ECM (Command Modern Operations 1.04)

That will be my last contribution to try to improve CMO around here.....only bug reports from now on. I wish you, Dimitris, too all the peace in your heart.




Dimitris
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RE: Automatic evasion

Post by Dimitris »

Thanks for the video. So, your point is that the typical fighter-borne ECM systems are not deception-only (DECM in CMO), but they also serve a noise function (OECM in CMO), even at a much lower power level compared to escort/standoff jammers. You could have opened with that and saved both of us a lot of grief.

We'll discuss this with our SME contacts and see how and where this may apply.
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SeaQueen
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RE: Automatic evasion

Post by SeaQueen »

ORIGINAL: thewood1
Don't forget that the game covers almost 70 years of combat across a hundred different forces. AAW tactics change over time and between countries. I think many of the posters are way over-simplifying how this gets designed, let alone executed.

There's a lot of oversimplifications of oversimplifications going on if you ask me. Depending on the nature of the oversimplification in question, it might not be a bad thing, within limits. (How's that for a basically useless statement?)

One of the dangers of a detailed game like Command is for people to focus on the details. When things don't behave exactly the way they think they ought to, they fixate on the details that they believe will produce the result they expected to see. I'm not always sure that people's expectations are necessarily accurate, though. In that sense, games like CMO, without access to the classified details, must be content to make imperfect representations of other imperfect representations.
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SeaQueen
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RE: Automatic evasion

Post by SeaQueen »

To boot, if you stay low in CMO your radar, even it it has no look down/shoot down abilty you will get a good fix on any high flying target while your opponent aircraft, if not eqipped with a modern advanced radar with LD/SD-ability will have large problems getting a weapons quality track on your aircraft that is flying at minimum level over the sea.

I think you're misunderstanding lookdown/shootdown. All lookdown/shootdown means is that the radar is a pulse doppler radar. That means within some limits, a radar is better at picking a target out of the ground clutter by taking advantage of Doppler shift on the returned radar signal. All things being equal, a low altitude aircraft SHOULD have an easier time picking out an aircraft above it due to the absence of ground clutter. A look up situation is actually ideal, and there's a lot of advantages to having a low CAP looking up, using ground clutter and terrain masking to avoid or delay detection. That's not necessarily wrong.

Lookdown/shootdown means that the radar has the ability to potentially negate that advantage by being able to better pick out targets from the clutter, and CMO does represent that fairly well. It's just missing the missile kinematics piece. That doesn't mean that the advantages enjoyed by a less advanced radar looking up aren't real.
tiag
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RE: Automatic evasion

Post by tiag »

ORIGINAL: Dimitris
....So, your point is that the typical fighter-borne ECM systems are not deception-only (DECM in CMO), but they also serve a noise function (OECM in CMO), even at a much lower power level compared to escort/standoff jammers.

Definitely. 100%. The main differences between what a dedicated escort/standoff jamming platform like the EF-111 or the EA-6 (with pods labeled as OECM in CMO) and a self-protection jammer (labeled as DECM in CMO) are of course the power available/gain (which translates in range), number of jamming channels/antennas, direction of ECM signal and modes of operation. Particular older DECM pods did not have as many modes as the dedicated platforms. But BOTH kinds of pods have the ability to delay to break/deny the enemy radar tracking solution. And that applies against airborne radars (as my video shows) as well as to air defence radars (I can make a video showing the effect).

Just to give some few additional information from random sources, different eras:

(1) Jane's Radar and Electronic Warfare Systems
"AN/ALQ-188A(V) Electronic Countermeasures
(ECM) system

...ALQ-188A(V) is capable of producing over 30 technique
combinations and is programmable from an RS-232 source. The technique types include noise (spot,
barrage or swept spot), velocity gate pull off, narrowband repeater noise, pseudo-random noise, random
Doppler, range gate pull off, cover pulse, false target, and Amplitude Modulation (AM) (blink, random
blink, fixed AM, swept square wave, sequenced AM). The equipment's antennas are circularly polarised
with coverage of ±30º for low gain and ±15º for high gain..."

(2) Fighter Weapons Review Spring 87, Page 22

"William Tell 86 provided competitors with yet more challenging combat profiles. Profile IV, a mass raid scenario, presented the competing teams with a strong, multi threat challenge. Designed to exercise
BASIC strategic air defense concepts in area defense againstan ECM-employing threat....

...The ECM signature of the profile was treated with the same concern for fair competition.
The F- 16 adversaries, which staged out of Mac0ill AFB, carried ALQ-131 pods each capable of producing an equal level of degradation for all types of competitor radars (F-4C/D, F-1 5A/C, CF-1 8), depending on the pod setting selected."

(3) Fighter Weapons review Summer 85, page 31
AN·ALQ 167 ECM POD
"The ALQ-167 is a super training pod against all current ADTAC/AC air-to-air fighte rs (F-4, F-106, F-15, and F-16).....
Image

(4) Jane's Radar and Electronic Warfare Systems
"ALQ-184(V) retains the same dimensions as ALQ-119(V), provides contiguous sub-band frequency coverage and is able to generate transponder, repeater and noise jamming modes"

There are many other examples, even older ones. For example, one of the first pods used in Vietnam was the QRC-160, better known as the AN/ALQ-87 (DBID #27342 in CMO) could operate with barrage as well as modulated noise.
This pod was carried by several tactical aircraft as >DECM< (The D here is for Defensive) and could perform the following central jobs:
Deny range and azimuth information to the Fire Can radar
Deprive range, altitude and azimuth information for the Fan Song (SA-2 radar)
Jam the position beacon (down-link) in the sustainer section of the SA-2 missile



boogabooga
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RE: Automatic evasion

Post by boogabooga »

ORIGINAL: Dimitris

Thanks for the video. So, your point is that the typical fighter-borne ECM systems are not deception-only (DECM in CMO), but they also serve a noise function (OECM in CMO), even at a much lower power level compared to escort/standoff jammers. You could have opened with that and saved both of us a lot of grief.

We'll discuss this with our SME contacts and see how and where this may apply.

Without getting too far OT, I suspect a similar issue exists where many radars have some ESM or ELINT capability "baked in"- where they can detect (in passive mode) the bearing of a jamming signal or even possibly other radar emissions operating over their coverage band.
The boogabooga doctrine for CMO: Any intentional human intervention needs to be able to completely and reliably over-ride anything that the AI is doing at any time.
LargeDiameterBomb
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RE: Automatic evasion

Post by LargeDiameterBomb »

I am aware of how radars work at approximately an intermediate non-professional non-classified information level.

But you are right that my description of things was sloppy and might easily be taken as faulty,


What I meant to say was

"To boot, if you stay low in CMO... you will get a good fix on any high flying target while your opponent aircraft, if not eqipped with a modern advanced radar with LD/SD-ability will have large problems getting a weapons quality track on your aircraft that is flying at minimum level over the sea [as long as the wave height corrsponds to at least something like sea state 3 or maybe 4, going by the Douglas scale]".


I just removed the following from the first sentence "your radar, even it [sic!] it has no look down/shoot down abilty" (Original typing error marked by me)
and added the last part within brackets now for maximum clarity.
LargeDiameterBomb
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RE: Automatic evasion

Post by LargeDiameterBomb »

Very good post, tiag.


I remember mentioning the same thing - that self-protection jammers (SPJs) (Called DECM in CMO) are in principle really the same as an escort jamming pod (called OECM in CMO) but with less power and as you state less antenna coverage, probably fewer antennas, a more automatic operating procedure (generally at least - for instance in one-seater fighters) and so on in a thread talking with DWReese about the missile evasion "problem".

I suggested that to escape the "missile evasion pattern of death" "a roll of the dice" should be done at missile launch instead of at the endgame calculations, if the aircraft is eqipped with a SPJ, perhaps after a period affected by OODA loop time and profiency of pilot, and if a SPJ pod as of now has a 30 % chance of defending against a missile a "roll of the dice" under 30 would mean that the self protection jammer has broken lock of the SARH guided missile or illuminator and the missile immediately veers of course very noticcably and the pilot in the defending airplane being attacked is given a chance to escape on afterburner instead of defending kinetally against the missile for maybe 15-20 seconds after which he is closer to the firing missile battery.


I didn't have the excellent sources you've gathered though.

But I would much rather see DECM pods work as weak OCM pods do, though, which I believe is more in tune with how SPJs work in real life.


Good work with your excellent post.
tiag
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RE: Automatic evasion

Post by tiag »

"a roll of the dice" should be done at missile launch instead of at the endgame calculations

Yes, that could be indeed an option. Another solution could be to apply the similar OECD algorithm to the DECM noise jamming (perhaps with a smaller cone from the nose of the acft and less power to simulate typical burnthrough ranges). Then (almost) no additional code to write, simply implement a bad tracking solution for the DECM pods this way and no missile can be correctly fired.
Azimuth information is more or less preserved, but range not (as in the video).

IMO, that would boost the realism of CMO in the EW by orders of magnitude!
tiag
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Re: Automatic evasion

Post by tiag »

@Dimitri

Do you have any update about the implementation of jamming pods as described in my post above (February)?
https://www.matrixgames.com/forums/view ... 5#p4962545

Regards

Tiago
thewood1
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Re: Automatic evasion

Post by thewood1 »

Did it get posted as a recommended change in the change request thread?
tiag
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Re: Automatic evasion

Post by tiag »

I dont know. Can you please put a link for it here?
thewood1
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Re: Automatic evasion

Post by thewood1 »

Well, you would know if you posted it, I hope.

https://www.matrixgames.com/forums/view ... 1&t=341588
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