Radar detection simulation

Hello,

I hope there wasn't another thread regarding this same subject and if so, I'd kindly ask the moderator to link me to that one instead of putting it wrong here! I'd like to address a few questions to those who have some knowledge/experience on real radars performances for the basis of this subject besides a few remarks related to my initial questions about the actual radar performances simulated in our DCS.

Q1. Are modern fighter aircraft and awacs radars able to see or even lock (fighters only) other aircraft flying in a dense clutter environment (such as below a mountain, hill, city) from any look down angle, unrestricted?

Q2. Are there real surface vessels (ships) radars able to lock targets that fly over water well below 10 meters AGL, for example at 2 meters above the water constantly and from what range can the lock become effective if so?

R1. After plenty of hours of testing, it seems that all of our simulated fighters radars (both US and Russian fighters have the same abilities) can track and lock other airplanes which fly in a non-notch condition from a very high look down angle (sometimes even from 80 degrees considering that the locking plane will have to pitch down the nose to keep the target within the gimbal's limits) and from distances from as high as 40-50nm (as for an F-14B, F-15 and F-18) no matter how dense the actual clutter might be (a mountain behind, a city or simply the earth surface). A 40000ft+ fighter (Su-27, F-18, F-14, F-15, etc.) can rapidly track and lock a head to head approaching fighter that hugs the terrain at around 5-8 meters AGL constantly.

R2. I can see that there's "a new boat in town", called Type 052B/C which can lock my plane flying as low as 2-3 meters over water (using autopilot) and killing it with HHQ-9 from plenty of kilometers away! If this ship's radar is so capable, why isn't the Ticonderoga or Moskva radars able to do the same as well? I'm not a radar expert, but if the radar beam can scan below the horizon (in the case of ships probably), how would the reflections that bounce back from the water surface (a very low but present reflection) affect the data signals? Just asking, isn't the radar suppose to have great difficulties to lock it in such conditions?

Cheers!

Hello,

 

I hope there wasn't another thread regarding this same subject and if so, I'd kindly ask the moderator to link me to that one instead of putting it wrong here! I'd like to address a few questions to those who have some knowledge/experience on real radars performances for the basis of this subject besides a few remarks related to my initial questions about the actual radar performances simulated in our DCS.

 

Q1. Are modern fighter aircraft and awacs radars able to see or even lock (fighters only) other aircraft flying in a dense clutter environment (such as below a mountain, hill, city) from any look down angle, unrestricted?

 

Q2. Are there real surface vessels (ships) radars able to lock targets that fly over water well below 10 meters AGL, for example at 2 meters above the water constantly and from what range can the lock become effective if so?

Not a radar expert, but...

Q1: Yes, the "look-down, shoot-down" (I hate this marketing phrase so much) capabilities of the radar come from 4th generation fighters' pulse Doppler radar. By comparing the velocity of radar returns to the velocity of the aircraft, the radar filters out any returns that would be slow moving or stationary objects on the ground. Radar computer sophistication changed dramatically throughout the history of PD radar, so the filters are much better now than they were initially. But in theory there is no reason why a mountain, hill, city, or any other random ground clutter will matter. Because it is not moving the radar will filter it and only see the airplanes that are moving at a speed greater than the Doppler filter.

Q2. It is possible, but the radar should be limited by line of sight. However, the actual radar is usually mounted on top of the ship a hundred or more feet (30m) above the water line. This is true for the Type 52's Band Stand radar as well. This means that the radar can see all the way to the water's surface for a decent distance away from the ship. It would be able to see up to 2-3m above sea level at a slightly longer distance. A quick check shows that the radar can see to the surface at about 20 kilometers. So it is possible.

Not a radar expert, but...

Q1: Yes, the "look-down, shoot-down" (I hate this marketing phrase so much) capabilities of the radar come from 4th generation fighters' pulse Doppler radar. By comparing the velocity of radar returns to the velocity of the aircraft, the radar filters out any returns that would be slow moving or stationary objects on the ground. Radar computer sophistication changed dramatically throughout the history of PD radar, so the filters are much better now than they were initially. But in theory there is no reason why a mountain, hill, city, or any other random ground clutter will matter. Because it is not moving the radar will filter it and only see the airplanes that are moving at a speed greater than the Doppler filter.

It's understandable now. I know little about radar capabilities first of all and what I know is a piece of this and that, but nothing complete. So yeah, if the newest radars are automatically switching between pulse and doppler (I now believe that that's what pulse-dopplers actually do) according to target condition (in and out of clutter, with closure rate or with zero closure rate) then, indeed, it's very plausible that no matter what's behind a closing or even notching target (hill, building, santa^), the radar would change to a mode that will try to keep the target locked. At least this is what I believe now based on your explanation.

Q2. It is possible, but the radar should be limited by line of sight. However, the actual radar is usually mounted on top of the ship a hundred or more feet (30m) above the water line. This is true for the Type 52's Band Stand radar as well. This means that the radar can see all the way to the water's surface for a decent distance away from the ship. It would be able to see up to 2-3m above sea level at a slightly longer distance. A quick check shows that the radar can see to the surface at about 20 kilometers. So it is possible.

Wow, so they've really evolved these radars quite well then, if nothing can't escape a radar lock even if it physically touches the water from as long as 20 kms away (if that's what you say).

Thank you!;)

It's understandable now. I know little about radar capabilities first of all and what I know is a piece of this and that, but nothing complete. So yeah, if the newest radars are automatically switching between pulse and doppler (I now believe that that's what pulse-dopplers actually do) according to target condition (in and out of clutter, with closure rate or with zero closure rate) then, indeed, it's very plausible that no matter what's behind a closing or even notching target (hill, building, santa^), the radar would change to a mode that will try to keep the target locked. At least this is what I believe now based on your explanation.

 

 

 

Wow, so they've really evolved these radars quite well then, if nothing can't escape a radar lock even if it physically touches the water from as long as 20 kms away (if that's what you say).

 

Thank you!;)

Modern radars are very capable. That being said, DCS radar modeling is not really radar physics based much (too processor intensive). At a guess its more rules based. But the earlier poster was right, PD radars are quite powerful in terms of look down shoot down, or better yet, look up shoot down scenarios. PESA and AESA are even better. Ship based ADA will pretty much be able to spot you on the horizon, which because the antennas are elevated will be a significant distance. Attacking modern ships is an exercise in using enough airplanes firing enough missiles to saturate the ships air defenses. To attack a modern DD you'd be talking dozens of missiles fired from standoff ranges in coordinated strikes. A single aircraft really shouldn't stand much of a chance against a ship, nor be able to carry enough firepower to really threaten it.

Hmm, sorry but I guess I should take back some of my words though, cause no matter how strong the radar may be, the notching (at least the 1st notch) in clutter environment (hill or buildings behind you) should break the lock because: the doppler radar will see your closure rate as that of the ground and the pulse will be full of clutter, so there should be no way left to keep the target tracked/locked. Out of notching through clutter, yes, the radar has at least one mode of keeping you locked. I don't know about how good a PESA/AESA radar does when it meets a notching target through the clutter, but I guess the PD loses it there.

Hmm, sorry but I guess I should take back some of my words though, cause no matter how strong the radar may be, the notching (at least the 1st notch) in clutter environment (hill or buildings behind you) should break the lock because: the doppler radar will see your closure rate as that of the ground and the pulse will be full of clutter, so there should be no way left to keep the target tracked/locked. Out of notching through clutter, yes, the radar has at least one mode of keeping you locked. I don't know about how good a PESA/AESA radar does when it meets a notching target through the clutter, but I guess the PD loses it there.

Yeah its more complicated than that IRL. Beamscanner as our resident radar expert should probably jump in at this point. Also consider radar logic, it has a track file of what is where and moving where, so if it sees something where it expects it even if its degraded its gonna say, yup thats probably our guy. Plus ground clutter and reflection doesn't look exactly the same as an aircraft which will reflect differently and so forth. So you have to start getting really specific about which radar system you mean and what exactly it can do. Something like the primitive MTI radars on the mig-23 and you are probably right. A late 80's early 90's radar on an F15C you are missing alot in terms of processing and other capabilities of the radar. Plus a 100mph "notch" is pretty generous, and while on early radars is probably right, I doubt it would be appropriate assumption for a modern AESA system. And you will almost never have 0mph closure rate for very long.

But I doubt much of this is actually detailed in DCS. In DCS is probably set up like: Is there a LOS (Y/N)? Should my radar be able to see the target at that range (based on radar specs, and some simplified number for radar signature number) what is the closure rate, and is it in "notch" criteria (probably again dependent on radar model) and then its some probability of breaking lock each X cycles.

Yeah its more complicated than that IRL. Beamscanner as our resident radar expert should probably jump in at this point. Also consider radar logic, it has a track file of what is where and moving where, so if it sees something where it expects it even if its degraded its gonna say, yup thats probably our guy. Plus ground clutter and reflection doesn't look exactly the same as an aircraft which will reflect differently and so forth. So you have to start getting really specific about which radar system you mean and what exactly it can do. Something like the primitive MTI radars on the mig-23 and you are probably right. A late 80's early 90's radar on an F15C you are missing alot in terms of processing and other capabilities of the radar. Plus a 100mph "notch" is pretty generous, and while on early radars is probably right, I doubt it would be appropriate assumption for a modern AESA system. And you will almost never have 0mph closure rate for very long.

 

But I doubt much of this is actually detailed in DCS. In DCS is probably set up like: Is there a LOS (Y/N)? Should my radar be able to see the target at that range (based on radar specs, and some simplified number for radar signature number) what is the closure rate, and is it in "notch" criteria (probably again dependent on radar model) and then its some probability of breaking lock each X cycles.

Thanks Harlikwin and everyone else,

This is a very interesting discussion and I appreciate the level of information shared by you guys to those like myself and others about the level of performance that the new radars are capable of. Knowledge is beautiful;)!

On 9/27/2019 at 8:16 AM, mattag08 said:

Not a radar expert, but...

 

Q1: Yes, the "look-down, shoot-down" (I hate this marketing phrase so much) capabilities of the radar come from 4th generation fighters' pulse Doppler radar. By comparing the velocity of radar returns to the velocity of the aircraft, the radar filters out any returns that would be slow moving or stationary objects on the ground. Radar computer sophistication changed dramatically throughout the history of PD radar, so the filters are much better now than they were initially. But in theory there is no reason why a mountain, hill, city, or any other random ground clutter will matter. Because it is not moving the radar will filter it and only see the airplanes that are moving at a speed greater than the Doppler filter.

 

Q2. It is possible, but the radar should be limited by line of sight. However, the actual radar is usually mounted on top of the ship a hundred or more feet (30m) above the water line. This is true for the Type 52's Band Stand radar as well. This means that the radar can see all the way to the water's surface for a decent distance away from the ship. It would be able to see up to 2-3m above sea level at a slightly longer distance. A quick check shows that the radar can see to the surface at about 20 kilometers. So it is possible.

Good answer but it is the frequency and not the speed of the radar pulse that changes. Higher frequency when hot aspect lower when cold

On 10/23/2019 at 7:36 PM, 85th_Maverick said:

So yeah, if the newest radars are automatically switching between pulse and doppler (I now believe that that's what pulse-dopplers actually do)

I don’t think PD radars change between a pulse scan and then a Doppler scan as they should be able to have filters and process both from the same return