AWG-9 target separation

[mattag08]

At some point in the last year the modelling of two or more contacts being identified as a single return by the AWG-9 was implemented. This was changed in a patch at one point and has now become quite excessive. Targets will no longer breakout if they are within 100 m or so of each other. In general, the likelihood of properly detecting all aircraft in a 2-4 aircraft flight is near zero. I'm not an expert in the AWG-9 or on military radar, but I have doubts about the accuracy of this model (or perhaps it's a bug) for a few reasons:

 

1. The AWG-9 is extremely powerful (in transmit strength) eclipsing some 4th gen radars that were built after it. This should offer higher probability of detection.

 

2. There are situations where the radar sweep can fit between the two contacts yet they are not discriminated as discrete contacts on the TID. There are other situations where the DDD returns are obviously two distinct returns, but the TID does not display them as such.

 

3. Normal U.S. Navy combat training and tactics on BVR weapons employment are invalid and unusable with the current implementation.

 

4. The AWG-9 was built to simultaneously launch six AIM-54s at large formations of enemy aircraft due to the danger of the nuclear threat, meaning discrimination of targets in formation and building a trackfile on each to guide AIM-54s would be a high priority.

 

A couple of gameplay reasons for a potential change:

1. The modelling of the radar is something the player (or perhaps even the developer) cannot know is 100% accurate to reality, so it would be good to err on the side of improved gameplay experience. I like the idea of late breakout contacts, but if it only ever happens at very short ranges regardless of contact separation, then tactics cannot be executed properly it is a very annoying experience to constantly end up unable to employ weapons on all aircraft in an enemy flight.

 

2. Enemies flying in combat spread should be observable as distinct contacts. If an enemy is not attempting to hide himself in a wingman's radar return by flying an extremely tight formation or behind his wingman, the radar should be able to discriminate between them.

 

3. It is impossible to use Jester to sort targets with another player if the TID does not display them as independent targets, which makes multiplayer BVR frustrating.

Edited July 15, 2020 by mattag08

[TLTeo]

To answer your first question at least, power and resolution are entirely unrelated. Resolution is limited by antenna dish and/or computing power in processing the returns, not in how much radio energy is emitted by said antenna dish.

[mattag08]

Hmm, I certainly understand that the most important items in resolution are the beam width and the bandwidth of the transmitted pulse. I changed the wording, since resolution is probably not the right word. This has a good explanation: https://www.richardsonrfpd.com/docs/rfpd/Radar_Tutorial_Book1.pdf

 

However, I do not know the beam width of the AWG-9. I would certainly love to know it.

[Naquaii]

The AWG-9 in our F-14B module is modelled after data we have on the real thing. Unfortunately this is one of the areas in which the age of this radar shows.

 

This has also been extensively tested by SMEs with experience of the real thing. It's just one of those disadvantages that you have to work around.

[mattag08]

Why do separate, distinct targets appear in RWS or on the DDD, but not TWS?

[Naquaii]

A human could in some cases discern that a return is multiple targets where the computer algoritms wouldn't.

[Santi871]

TWS is constantly trying to determine whether a new hit should be associated to an existing trackfile, which implies that there's always going to be room for error and sometimes different hits might be correlated to the same track, or the opposite, hits on the same target might create separate tracks even though there's only one target present.

 

RWS doesn't try to correlate anything, so as long as the radar determines there's two separate hits, they'll show as such. However, targets can be so close together that they fall within the radar's resolution and so even in RWS they'll show as a single target.

[BreaKKer]

And there isn't a any way to split a TWS track into two contacts? Like MULTI TGT? Though, I am pretty sure MULTI TGT is just for datalink.

[RustBelt]

The TID is not the Primary display for the AWG-9. It's 1970's tech working harder than it has any right to be as it is. Always work DDD to TID. Don't trust the re-programmed Pac-man machine without cross checking it.

[mattag08]

I'm well aware. The point is if the TID isn't displaying independent contacts in TWS you cannot launch an AIM-54 at each aircraft in the group. The only solution is to STT individual contacts, but this means you will still have untargeted aircraft which means a lost BVR fight. Any situation where the enemy # > friendly # means an instant loss.

[QuiGon]

I'm well aware. The point is if the TID isn't displaying independent contacts in TWS you cannot launch an AIM-54 at each aircraft in the group. The only solution is to STT individual contacts, but this means you will still have untargeted aircraft which means a lost BVR fight. Any situation where the enemy # > friendly # means an instant loss.

Welcome to older radar tech!

[RustBelt]

Exactly, There's many reasons the D replaced the AWG-9 with a more modern Radar.

[falcon_120]

I'm well aware. The point is if the TID isn't displaying independent contacts in TWS you cannot launch an AIM-54 at each aircraft in the group. The only solution is to STT individual contacts, but this means you will still have untargeted aircraft which means a lost BVR fight. Any situation where the enemy # > friendly # means an instant loss.

 

Not if you fly in pairs, like the US Navy actually does. But in any case, it is what it is, I would love that ED gets this level of detail in other radars, right now its impossible to get only one contact even at 80nm with 2 contacts flying 1 meter apart.

[mattag08]

Not if you fly in pairs, like the US Navy actually does. But in any case, it is what it is, I would love that ED gets this level of detail in other radars, right now its impossible to get only one contact even at 80nm with 2 contacts flying 1 meter apart.

Enemy 4-ship is the issue mate.

[falcon_120]

Enemy 4-ship is the issue mate.

 

Eventually they will appear on radar as separate targets and given phoenix range i think you can still launch several missiles wait to pitbull and ran before they can do the same. I mean that is very situational but should not mean that you dont have the upper hand, you still get the bigger stick and the speed to ran away over most of everything there is.

[TLTeo]

Uh doing some back of the envelope math:

 

1) the diffraction limit for the an X-band radar like the AWG-9, assuming a dish size of 1 meter and a wavelength of 1cm, is on the order of R~1cm/1m~10^-2 radians.

2) the angular size of two aircraft flying 100 meters apart at a distance of 100km (so, 60 nm or so) is ~10^2m/10^5m ~10^-3 radians, so the awg-9 shouldn't be able to tell the two apart. In fact, no X-band airborne radar should be able to - you would need the aircraft to be ~1km apart (or a stupidly large dish, or some fancy AESA/PESA dark magic, or a W/millimeter radar but those get screwed over by the atmosphere).

 

Did I miss anything obvious? Being a couple of miles apart is pretty standard in tactical formations anyway, so I don't see the issue.

Edited July 16, 2020 by TLTeo