GMT mode

[Annelid]

Can GMT ground radar mode detect low flying helicopters?

[Bananabrai]

In that case it would detect low flying planes as well. As GMT uses doppler (at least to my knowledge), there may be a speed gate.

It generally detects things that are faster moving than stationary. But to not have air targets on there, objects with a certain speed may get filtered out.

 

So the attack computer sees doppler returns for 1-XXX knots and displays things 1-100kts for example.

So a Lambo at full speed might not be displayed. But I have to admit, I can't say anything for sure.

[QuiGon]

20 minutes ago, Bananabrai said:

In that case it would detect low flying planes as well. As GMT uses doppler (at least to my knowledge), there may be a speed gate.

It generally detects things that are faster moving than stationary. But to not have air targets on there, objects with a certain speed may get filtered out.

 

So the attack computer sees doppler returns for 1-XXX knots and displays things 1-100kts for example.

So a Lambo at full speed might not be displayed. But I have to admit, I can't say anything for sure.

 

That's how it works in real life, but does it work like that in DCS as well?

 

Also, will it be possible for vehicles to notch the GMT radar?

Edited January 22, 2021 by QuiGon

[Harker]

I don't know how GMT will work, but I've been able to both detect a low flying helicopter in MAP mode with EXP2/3 and track it with FTT, getting correct heading and speed info on the brick.

[Bananabrai]

@QuiGonI think you are more of an expert in terms of 'how does it work in DCS'.

 

Well I assume stationary targets would not be detected and you would need to switch to RBGM (Real-Beam-Ground Mapping) / SAR / EXP

So notching in that case would be done by simple stopping the vehicle. 

I cant think of other notching techniques.

Edited January 22, 2021 by Bananabrai

[QuiGon]

28 minutes ago, Harker said:

I don't know how GMT will work, but I've been able to both detect a low flying helicopter in MAP mode with EXP2/3 and track it with FTT, getting correct heading and speed info on the brick.

 

That's interesting. AFAIK MAP mode works with pulse only (not pulse doppler), so I wonder if you achieved that over land (ground clutter) or over sea (no ground clutter)?

 

 

25 minutes ago, Bananabrai said:

@QuiGonI think you are more of an expert in terms of 'how does it work in DCS'.

 

Well I assume stationary targets would not be detected and you would need to switch to RBGM (Real-Beam-Ground Mapping) / SAR / EXP

So notching in that case would be done by simple stopping the vehicle. 

I cant think of other notching techniques.

 

 

I was thinking of a vehicle, driving at a speed that is within the speed gate, but in a direction perpendicular (90°) to the Hornet.

Edited January 22, 2021 by QuiGon

[Bananabrai]

Sorry, I misunderstood you. That of course could work as well. I think the challenge for the vehicle is to know that.

But to look at it the other way round, if you are scanning and a convoy is by chance 90° to you, you should not be able to see that.

[Northstar98]

Hmm, I wonder if GMT isn't actually doppler, but GMTI, i.e a pulse RADAR (like MAP), but using an MTI.

 

Mind you, in Wag's video, you can see the speed and heading of detected moving targets, which is more indicative of a doppler RADAR.

Edited January 22, 2021 by Northstar98

[Harker]

2 hours ago, QuiGon said:

 

That's interesting. AFAIK MAP mode works with pulse only (not pulse doppler), so I wonder if you achieved that over land (ground clutter) or over sea (no ground clutter)?

 

I wasn't clear enough, I didn't detect the helo as a brick, I just found its return manually with MAP. I already knew where to look for it, this was in the context of a test. It was flying low and relatively slow, over a river, so I could pick it up. Only after I switched to FTT and successfully tracked it, I got a brick with heading and speed.

I doubt it could pick it out over land, if it was moving, unless we're talking about a desert or something equally featureless.