Navigation radars should not allow type classification

[gosnold]

Hi team,

I have a problem with navigation radars (for instance the generic navigation radar #1916) allowing advanced ESM sensor to perform type classification. One of the points of fitting navigation radars on warships is to pass for commercial traffic, but in CMO advanced ESM receivers (like the one on the P-8 in the attached saved) can tell if a contact is a merchant or not just based on their nav radar. For instance, if you fit the generic nav radar on a carrier, they will classify it as a CVN based on that alone!

Same thing on aircraft navigation radars, they should not allow to tell type.

[thewood1]

When I ran the save, I dropped three of the contacts on the IDed ships. As the scenario progressed, the ships were IDed as SKUNKs only through ESM on the nav radar emissions. They were then type classified by the IRST on the F-35. But they still are listed as ESM contacts because of the emissions, but remain IDed because of the IR visual contact. That seems right. If not for the ISRT detection, they would have stayed SKUNKs for a bit.

When first of the three is classified...

Screenshot 2023-12-02 154135.jpg (604.96 KiB) Viewed 996 times

And a few seconds later the other two...

Screenshot 2023-12-02 154235.jpg (205.75 KiB) Viewed 996 times

Nothing "illegal" as far as I can see.

[gosnold]

Right, I'll provide a save a bit earlier with the nav radar turned on on the CVN.

[gosnold]

Here you go, I made a mistake in the initial file, it's the OPFOR with the P-8 that does the detections, sorry about that. In this file you have that, the CVN has a generic nav radar and still gets classified as CVN based on that.

[gosnold]

I'm using build 1328.11

[Kobu]

Hi

Not only the CVN, but also civil or transport ships are classified based on that. I don't know if it is possible to make a sufficient distinction in real life between different navigation radars to classify a ship.
In my opinion, just "generic navigation radar" should not be able to classify a ship.

Regards

[thewood1]

Hi

Not only the CVN, but also civil or transport ships are classified based on that. I don't know if it is possible to make a sufficient distinction in real life between different navigation radars to classify a ship.
In my opinion, just "generic navigation radar" should not be able to classify a ship.

Regards

I think you should be able to easily classify a ship or group of ships based on a nav radar. Each manufacturer's sets have some distinct emissions. How detailed you get is the main question and what does that mean in game terms. I think the issue here isn't just classification based on nav radar, its the OP added a nav radar to the ship and didn't mention that. My guess is its not a nav radar classification issue. Its a broader issue around how the game classifies a contact based on emissions not in the database.

Frankly, I'm not sure its a very big deal. Its only going to impact units that have a non-organic sensor added. I'll also mention its VERY important for a player asking for help to give full disclosure on any mods they have made. That nav radar is not organic to the unit. It would have saved a lot of time and hunting to know that right off.

One last thing, in a modern scenario almost all merchant ships will have an auto ID. Thats how you hide a ship in crowded waters.

[gosnold]

No it's not an issue with me adding the radar, if I use the Liaoning instead (which has an organic generic nav radar) it's the same. Also merchants get classified as merchants even if they have the same generic radar.
The nav radar on warships are off the shelf civilian radars so it's not possible to tell them apart.

Regarding auto ID, it's true in real life ships have AIS. However that can be spoofed, so it should not be relied upon. And some civilians turn off their AIS to do illegal activities.

[thewood1]

Double post while editing

[thewood1]

The issue with ID is a valid question. I'm just saying its good form to tell people trying to help that made made changes to the unit. Otherwise you go down different paths trying to sort it.

Just keep in mind that in real life, there is no generic radar. I'm just saying that IRL, you can narrow down the radar type, even it still leaves classification somewhat indeterminate.

And I'll point out again, in the last 40 or so years, its the transponder that IDs ships, not just radar or ESM detection. If I was hiding a carrier in a large body of water, its not the nav radar emissions I would depend on, its a fake transponder.

[gosnold]

Yeah sorry about the modifications, I did not think that would complexify the situation, I should have made an example with the a default platform.

[bsq]

A navigational radar should not, in and of itself, be able to ID any contact past the point of Azimuth and Range.

Now then there is AIS (is this abstracted - I have no idea) but it will give you MMSI (9 digit code assigned to that transponder) provided its on and not being spoofed.

Finally and most importantly there is SEI. DIrect quote from the the web...

Specific emitter identification (SEI) is the process of discriminating different emitters based on the radio fingerprints extracted from the received signals. Without complex parameter adjustment, radio fingerprints can be efficiently extracted by end-to-end deep learning models.

That's generally how its done, each radar is unique (even within a batch - myriad of reasons why) and has a fingrprint, be this RF characteristics or pulse parametric (timing) characteristics - measurable with a good enough ESM/ELINT system, this is easy. Might be abstracted, might not, but as a technique it exists and is valid.

[thewood1]

A good friend of mine used to sell maritime navigation systems from various vendors in Rockport, MA. He said every radar is slightly different in its emissions based on a large number of factors from components to manufacturing settings, to maintenance tuning, to purpose built signal IDs. The FCC and other agencies in the US only set broad guidelines for emissions. His main comment is that it requires significant sophisticated signal processing to sort out the nuances in an RF dirty environment.

He felt it was unrealistic to expect ship-level ID on a commercial nav radar, but if its OEM radar, you could probably get a class. And there's no international database on commercial nav radars to know exactly what set went to what ship. So if the nav radar is installed aftermarket, not likely to be a determining factor in classification. I think transponder issue should be an option. You can make all commercial ships IDed through the scenario editor. But how would you do that to hide a warship and make it look like a commercial ship? Most likely through lua.

[gosnold]

On the topic of AIS spoofing, even in peacetime the French warship are playing shell games with their MMSI:
https://twitter.com/auonsson/status/1732108548031525156

[bsq]

And there's no international database on commercial nav radars to know exactly what set went to what ship.

There is but it is reverse engineered (ie after the event). Think choke points and ports.

[thewood1]

Yeah, I assume someone somewhere is a large government agency is vacuuming up all the emissions and aligning them as a fingerprint for individual ships. I'm not sure if data is collected during manufacturing or not. It would be a big undertaking. Almost as big as collecting cellphone data...Oh wait!