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Jammer Effective Range

Posted: Tue Jun 27, 2023 7:03 pm
by HalfLifeExpert
What's a good rule of thumb for determining how far OECM Jammers can be effective in jamming?

I don't think there's a clear Range value in the DB.

Re: Jammer Effective Range

Posted: Tue Jun 27, 2023 8:14 pm
by DWReese
Of course it depends on the jammer, but using a EA-6 Prowler I generally start to be picked us as being jammed about 200-250 miles away. The reason that I know this is because I use the Editor an switch back and forth to see when it happens. I don't have the exact numbers, but I could find out for you, if necessary.

To what effect the jammer works is not known to me. The unit is either JAMMED, or not. I don't know to what degree. Obviously, as it gets closer, eventually the JAMMER no longer provides any protection.

Hopefully, this is what you were talking about.

Re: Jammer Effective Range

Posted: Tue Jun 27, 2023 9:55 pm
by HalfLifeExpert
I was thinking about it in the context of minimum warning attacks using things like the Prowler.

However effective a jammer is, the enemy will know that they are being jammed, which means they know you are there, somewhere.

In general, how would I know how close I would need to be so that me turning on my jammers provides not too much warning to my targets? (aside from very close of course)

Basically, I don't want to turn on the jammers too far out for them to be effective and give me away, but I also don't want to activate them too close and risk the enemy defenses firing first and blasting some of my aircraft.

Re: Jammer Effective Range

Posted: Wed Jun 28, 2023 12:19 am
by DWReese
It depends on what kind of radar the defenders have. If they have a long range radar, then they could detect high-flying objects hundreds of miles away. If your planes are coming in low, like 100 feet over the surface (I did that with some F-15s the other day) so might not be detected until you are 30-40 miles away.

Personally, I'd keep them on all of the time when they are in the air. You won't be able to know where they are coming from, and they don't necessarily mean that the defenders will be under attack,

Try that F-15 low altitude attack with a jammer and the defense won't see anything until the missiles (or planes) are almost on top of them. Jammers work great.

Re: Jammer Effective Range

Posted: Wed Jun 28, 2023 5:59 am
by Fido81
There isn't a simple rule of thumb because electronic attack doesn't work like that. Almost all of it is handled 'under the hood'. I think that's a good thing, because RF engineering is confusing.

Some key factors in CMO that I have found impact OECM effective range include:
- RF spectrum (if you have a jammer for bands A-D, but the enemy has an I-band radar, the jammer isn't going to do any good)
- relative altitude (you want to be able to draw a line between the radar, the strike package, and the escort jammers)
- bearing to radar being jammed (again, you want to be able to draw a line between the radar, the strike package, and the escort jammers; if the jammer has to be at a specific orientation to provide the effects, that needs to happen)
- generation of electronic warfare systems (newer jammers perform tend to perform better against older radars, and newer radars tend to perform better against older jammers)
- number of emitters on each side (I recall reading somewhere in the documentation that jammers can only impact a set number of transmitters)
- comms status (as a result of the prior factor)

Re: Jammer Effective Range

Posted: Wed Jun 28, 2023 5:59 am
by Fido81
There isn't a simple rule of thumb because electronic attack doesn't work like that. Almost all of it is handled 'under the hood'. I think that's a good thing, because RF engineering is confusing.

Some key factors in CMO that I have found impact OECM effective range include:
- RF spectrum (if you have a jammer for bands A-D, but the enemy has an I-band radar, the jammer isn't going to do any good)
- relative altitude (you want to be able to draw a line between the radar, the strike package, and the escort jammers)
- bearing to radar being jammed (again, you want to be able to draw a line between the radar, the strike package, and the escort jammers; if the jammer has to be at a specific orientation to provide the effects, that needs to happen)
- generation of electronic warfare systems (newer jammers perform tend to perform better against older radars, and newer radars tend to perform better against older jammers)
- number of emitters on each side (I recall reading somewhere in the documentation that jammers can only impact a set number of transmitters)
- comms status (as a result of the prior factor)

Re: Jammer Effective Range

Posted: Wed Jun 28, 2023 2:15 pm
by maverick3320
DWReese wrote: Wed Jun 28, 2023 12:19 am It depends on what kind of radar the defenders have. If they have a long range radar, then they could detect high-flying objects hundreds of miles away. If your planes are coming in low, like 100 feet over the surface (I did that with some F-15s the other day) so might not be detected until you are 30-40 miles away.

Personally, I'd keep them on all of the time when they are in the air. You won't be able to know where they are coming from, and they don't necessarily mean that the defenders will be under attack,

Try that F-15 low altitude attack with a jammer and the defense won't see anything until the missiles (or planes) are almost on top of them. Jammers work great.
I don't think that's the jamming, I think that's line of sight.

Re: Jammer Effective Range

Posted: Wed Jun 28, 2023 3:12 pm
by DWReese
You are correct, that is LOS, but I was talking about with the EA-6 behind it. Now, that's jamming. <G>

Re: Jammer Effective Range

Posted: Thu Jun 29, 2023 11:23 am
by blu3s
This morning, I conducted some testing to analyze the detection capabilities of different radars against an F-16A with and without some EW aircrafts

https://blu3ser.github.io/EW%20Distance.html

Let me know if you are interested in other testing on this topic.

Re: Jammer Effective Range

Posted: Thu Jun 29, 2023 1:16 pm
by CV60
blu3s wrote: Thu Jun 29, 2023 11:23 am This morning, I conducted some testing to analyze the detection capabilities of different radars against an F-16A with and without some EW aircrafts

https://blu3ser.github.io/EW%20Distance.html

Let me know if you are interested in other testing on this topic.
Very nice. Thank you for doing them. Possibly these and similar charts could be added as an appendix to the community manual?

Re: Jammer Effective Range

Posted: Thu Jun 29, 2023 2:21 pm
by Parel803
Looks impressive but I'm not sure how to read it. Sorry for that.

Also checked out your other page with logs. Very nice.

regards GJ

Re: Jammer Effective Range

Posted: Thu Jun 29, 2023 3:24 pm
by blu3s
Thanks for your words, in the end it is a very simple scenario with an attacking aircraft, an EW aircraft and a radar. In any CMO scenario the situation is much more complex so you can't draw too many conclusions, but you can get an idea of the effect of jamming. I have added other radars this time in a range of distances between 0 and 800 nmi. In all of them the jamming stops affecting in the step from 400 to 450 nmi.

I did some other researchs like adding more jammers or adding more sensors and see what happened.

Parel803, if you have any doubt you can write me via DM. The charts show on the Y axis the normalized detection (that is the distance at which the radar detects the aircraft divided by the theoretical maximum detection value) of an F-16A. On the X axis they go from -20 to 400 or 800 and show the distance (rounded) at which a jam aircraft is flying away the radar, except for the -20 value where there is no jamming present.


If I have time I would like to do the test grouping the radars by bands, with jammers that act in their band and others that do not and see the differences.

Re: Jammer Effective Range

Posted: Thu Jun 29, 2023 5:07 pm
by CV60
Test.jpg
Test.jpg (114 KiB) Viewed 4507 times
Just to clarify: Using this example, in a no jamming situation (Position A on this image), the 59N6 radar is detecting the F-16A at the theoretical maximum range for the F-16A's target aspect. If an EC-37 COMPASS CALL is located 10 nm from the 59N6 radar, it reduces the detection range of the 59N6 against the F-16A by 90% (Position B on this image). At 120nm distance from the 59N6 radar, both the J16 and the EA18 will reduce the 59N6 radar's detection range against an F-16A by about 10% (Position C). At 400nm distance from the 59N6 radar, the EC-37 COMPASS CALL will reduce the detection range against an F-16A by about 38% (Position D). Am I reading this correctly?

Re: Jammer Effective Range

Posted: Thu Jun 29, 2023 5:58 pm
by blu3s
In this example, yes, but keep in mind that in percentage terms it only applies when the detection range without jamming is equal to the theoretical maximum range.

The theoretical maximum range is the number shown in the db viewer (v498 iirc)

This means that the normalized value does not always represent a percentage reduction. For example, if the detection without jamming is 0.8 and with jamming at 20 nmi is 0.4, the percentage reduction is 50% rather than 60%.
CV60 wrote: Thu Jun 29, 2023 5:07 pm At 400nm distance from the 59N6 radar, the EC-37 COMPASS CALL will reduce the detection range against an F-16A by about 38% (Position D). Am I reading this correctly?
The percentages are correct but be careful with this one, this is 1-0.37 = 63% reduction

--Edit to say, if you mean a percentage reduction (difference btw no jamming detection vs jamming detection), all percentages are miscalculated, but if you mean as percentage over the theoretical max range then all are fine. See my reply to Parel803 question to further explanation

Re: Jammer Effective Range

Posted: Thu Jun 29, 2023 7:11 pm
by Parel803
Good evening,

Thank you both, much appriciated.
A question (as always :-)): would this be correct
=(A2 - B2) / A2 * 100
In A is the noJam value and in B is the value at range. Giving me a % of the Theoretical Max Range?

regards GJ

Re: Jammer Effective Range

Posted: Thu Jun 29, 2023 7:46 pm
by blu3s
That formula gives you the percentage reduction between the real detection without jamming vs. detection with jamming. What I mentioned here (I didn't write the /1 division):
blu3s wrote: Thu Jun 29, 2023 5:58 pm this is 1-0.37 = 63% reduction
If you want to get the percentage over the theoretical maximum range it should be

(Distance Detected / Maximum Range )*100

For example if your radar has a Max Range = 240 nmi and you detect the aircraft at 200 nmi, your percentage over the theoretical max range is (200 / 240 ) * 100 = 83.34%

If you introduced a jamming ac and you detect the aircraft at 150 nmi, your new percentage over the theoretical max range is (150 / 240) * 100 = 41,67%

The jamming decreases the detection range as follows: ( (detection range without jam - detection range with jam) / detection range without jam )* 100

In this example:

( (200 - 150) / 200) * 100 = 25%

I hope I have made myself clear, let me know if anything needs further explanation

Re: Jammer Effective Range

Posted: Fri Jun 30, 2023 12:24 pm
by blu3s
I have done a test by iterating the same scenario 100 times to assess the dispersion of the data. You can see the summary in the link https://blu3ser.github.io/EW%20Distance.html#dispersion

The test is done using an EA-18G as electronic attack aircraft. I would like to draw your attention to a specific finding: when engaging a Cheese Board radar, the detection range varies from 80% to as low as 10% of the theoretical maximum range.
dispersion.JPG
dispersion.JPG (41.58 KiB) Viewed 4407 times

Re: Jammer Effective Range

Posted: Fri Jun 30, 2023 2:10 pm
by Parel803
Blu3s,

Thanks again for your time and answer.

regards GJ

Re: Jammer Effective Range

Posted: Sat Jul 01, 2023 9:01 pm
by Fido81
blu3s wrote: Thu Jun 29, 2023 11:23 am This morning, I conducted some testing to analyze the detection capabilities of different radars against an F-16A with and without some EW aircrafts

https://blu3ser.github.io/EW%20Distance.html

Let me know if you are interested in other testing on this topic.
This is awesome - thank you for doing the research, and sharing it, and making it so easy to understand!

Re: Jammer Effective Range

Posted: Sun Jul 02, 2023 11:03 am
by Blast33
Nice work blu3s!
Thank you for sharing :!: