055 DDG Large Destroyer Thread

[Iron Man]

But it does tell you how wide it is, which makes it more like the 055's.

The thickness of the bar arrays in the 055 is more indicative of transmission technology. They are likely to be AESAs while the older, thin ones might be PESA.

The (presumed) IFF arrays on the carrier are far wider than either of the bar arrays on the 055 and as such do not inform us what the 055 arrays are. If you want to say that the 055 IFF arrays are upgrades of the ones on the 052D then I can also use that argument and say that either of the bar types could represent an 'upgraded' IFF due to their different shape. The fact is that the bar arrays on the 052D are different from the ones on the 055 which are in turn different from on the ones on the 17.

Regardless of their appearance, AESA vs PESA arrays are certainly not differentiated by how thick they are:



If I blotted out the lettering would you be able to tell me which one was AESA and which one was PESA? Of course not.

 

[Iron Man]

I have a feeling that if any HQ-9s were equipped on 055s that still used SARH/TVM guidance (doubtful sounding to me as I imagine they should have moved to ARH at least on 052D), it could probably be done by the X band AESAs instead.

The lack of up to date information as to what variants of HHQ-9 the 052C, 052D and 055 respectively use/are in service makes it hard to confidently determine what roles the radars may have. As is the lack of information as to what the state the quad pack MR SAM in development is, and what mode of guidance it has.

Which sources have said that the iteration of HHQ-9 on the 052D is ARH?

 

[Tam]

The (presumed) IFF arrays on the carrier are far wider than either of the bar arrays on the 055 and as such do not inform us what the 055 arrays are. If you want to say that the 055 IFF arrays are upgrades of the ones on the 052D then I can also use that argument and say that either of the bar types could represent an 'upgraded' IFF due to their different shape. The fact is that the bar arrays on the 052D are different from the ones on the 055 which are in turn different from on the ones on the 17.

The IFF arrays on the carrier are about the width of the Type 346A radar. The IFF arrays on the Type 055 are about the width of the Type 346B radar --- which is the ones on top of the Type 055's Type 346B radars, not the smaller ones. The IFF arrays on the carrier are not far wide off the mark, they would almost be the same. The IFF arrays on the Type 346 radars are the ones right on top of the main array, if that's what they are on the Type 052D, then the arrays positioned similarly on the 055, the Liaoning and the Shandong, are also their IFF. That's also in addition to the back of their IFF having a segmented appearance on the back like this strip on top of the HT-233 radar. That points to the IFF using a six or seven bit code, and the IFF arrays on the three ships have a similar number of segments.

Regardless of their appearance, AESA vs PESA arrays are certainly not differentiated by how thick they are:

View attachment 57360

If I blotted out the lettering would you be able to tell me which one was AESA and which one was PESA? Of course not.

If I could look at the back I can tell you which one is an AESA or a PESA. Can you?



In an AESA, each element has a PCB behind it, that holds an LNA, A/D converter, and the SoC that controls the shifters. That requires a frame to hold them.

In a PESA, you only have the circuit to manages the shifters. Every emitter is connected to a line feed, all these line feeds are connected to a single massive LNA. Actually that's only for the PESAs that use parallel line feed. Another type of PESA, which is common for SAM fire control, uses a horn that projects the signal to the back of the array which acts as a lens. Another type of PESA uses a serial line feed. You can tell them from the back or from the side. There is simply less complexity at the back of a PESA than an AESA.

 

[Iron Man]

The IFF arrays on the carrier are about the width of the Type 346A radar. The IFF arrays on the Type 055 are about the width of the Type 346B radar --- which is the ones on top of the Type 055's Type 346B radars, not the smaller ones. The IFF arrays on the carrier are not far wide off the mark, they would almost be the same. The IFF arrays on the Type 346 radars are the ones right on top of the main array, if that's what they are on the Type 052D, then the arrays positioned similarly on the 055, the Liaoning and the Shandong, are also their IFF. That's also in addition to the back of their IFF having a segmented appearance on the back like this strip on top of the HT-233 radar. That points to the IFF using a six or seven bit code, and the IFF arrays on the three ships have a similar number of segments.

No. The IFF arrays on the 17 are definitively wider than the 346 array below, whereas the bar array on top of the 346 on the 055 is slightly narrower than the 346 array. Don't try to spindoctor some kind of equivalency out of this with words, just look at the photos themselves. Regardless, the IFF arrays on the 052D sitting on top of the 052D are noticeably narrower than the 346 array, by about half in fact. Regarding their "segmentation", this indicates literally nothing except a "similar" (note you didn't claim "identical") number of blocks. Obviously they are all radars of some sort so it's not surprising that they are divided into segments. SPY-6 uses the same concept in the form of their RMAs.

If I could look at the back I can tell you which one is an AESA or a PESA. Can you?

No, I can't, and neither can you.

PESA:


AESA:

In an AESA, each element has a PCB behind it, that holds an LNA, A/D converter, and the SoC that controls the shifters. That requires a frame to hold them.

In a PESA, you only have the circuit to manages the shifters. Every emitter is connected to a line feed, all these line feeds are connected to a single massive LNA. Actually that's only for the PESAs that use parallel line feed. Another type of PESA, which is common for SAM fire control, uses a horn that projects the signal to the back of the array which acts as a lens. Another type of PESA uses a serial line feed.

Oh, a frame. How big a frame would I need to be to hold the LNA, A/D converter, and the SoC in this AESA T/R module?:

There is simply less complexity at the back of a PESA than an AESA.

Sure. Here is the YLC-2, an AESA:


Here is a more revealing view directly perpendicular to the face of the radar:


While I agree there is more complexity at the back of an AESA T/R module, it certainly doesn't have to be reflected in the form of what you end up seeing in the final product, and it certainly doesn't inform us what type of radar is sitting on top of the 055, the 052D, or the 17.

 

[Blitzo]

Which sources have said that the iteration of HHQ-9 on the 052D is ARH?

I wrote — I imagine, I.e. I believe, suspect or speculate.

I suspect that HHQ-9 on 052D could be or could likely be ARH because the ARH land based FD-2000 was already offered for export by the time 052D was emerging also because the 052D’s 346a has a square a array shape compared to the rectangular of 346 on 052C for the upper and lower C band arrays sandwiching the main S band, meaning I believe 346A is only S band.

 

[Tam]

No. The IFF arrays on the 17 are definitively wider than the 346 array below, whereas the bar array on top of the 346 on the 055 is slightly narrower than the 346 array. Don't try to spindoctor some kind of equivalency out of this with words, just look at the photos themselves. Regardless, the IFF arrays on the 052D sitting on top of the 052D are noticeably narrower than the 346 array, by about half in fact. Regarding their "segmentation", this indicates literally nothing except a "similar" (note you didn't claim "identical") number of blocks. Obviously they are all radars of some sort so it's not surprising that they are divided into segments. SPY-6 uses the same concept in the form of their RMAs.

IFF isn't radar. The segments are used to send a coded message which is replied in turn by another IFF.

No, I can't, and neither can you.

PESA:
View attachment 57367

This one is easy. You can tell this is a PESA because there is a feed facing the back of the array. I am not sure if you know what I am talking about.

AESA:
View attachment 57368

Without checking the back of the array for a serpentine S-feed, or for a large box structure at the center of the array, I am not sure if this array is positively an AESA or a PESA.



You cannot tell AESA or PESA from the face alone, you need to see this at the back and at the side.

Why is this radar a PESA?

Oh, a frame. How big a frame would I need to be to hold the LNA, A/D converter, and the SoC in this AESA T/R module?:

You would need a larger LNA to hold a higher voltage before breakdown. That's determined by power requirement.

Sure. Here is the YLC-2, an AESA:
View attachment 57370

Here is a more revealing view directly perpendicular to the face of the radar:
View attachment 57372

Its an AESA because the architecture is like this. The huge box that makes up the spine of the YLC-2 array contains modules in a serial fashion like this.





I am pretty sure the modules on the radars are huge.

To be honest, this is almost a quasi PESA because you have one module to service a whole series of receivers and transmitters within a linear element. However for it to be a true PESA, you must only have one LNA for the entire array, not one LNA per linear element.

While I agree there is more complexity at the back of an AESA T/R module, it certainly doesn't have to be reflected in the form of what you end up seeing in the final product, and it certainly doesn't inform us what type of radar is sitting on top of the 055, the 052D, or the 17.

Your single module needs to go into an assembly that looks like this. You haven't counted all the cooling equipment surrounding this, and the cables that goes at the back of this assembly.


[/quote]

 

[Tam]

I wrote — I imagine, I.e. I believe, suspect or speculate.

I suspect that HHQ-9 on 052D could be or could likely be ARH because the ARH land based FD-2000 was already offered for export by the time 052D was emerging also because the 052D’s 346a has a square a array shape compared to the rectangular of 346 on 052C for the upper and lower C band arrays sandwiching the main S band, meaning I believe 346A is only S band.

Sandwiching strip arrays are more likely to be IFF and communication arrays for the missile and the Type 346 on the 052C lacks any visible external IFF. Its very much like its land based contemporary, the HT233. You can see the arrays sandwiching the main octagonal array. The top one is IFF, and the bottom panels are communication.



Here's the kicker of this array. The entire main octagonal array itself is both tracking radar, missile guidance and illumination. This radar runs on C-band and so does the missile. Long range search functions are done by separate vehicles with other radars, like the ones I posted above.

Here are examples from within the Chinese defense industry of a dual band radar that has both search, track, and missile guidance functions on the same panel. The array on top is for search, acquisition and tracking. The array on the bottom is for the missile guidance, and it too is a square or needs to be symmetrical. If you want to know, this radar vehicle is for the HQ-16.

 

[Blitzo]

Sandwiching strip arrays are more likely to be IFF and communication arrays for the missile and the Type 346 on the 052C lacks any visible external IFF. Its very much like its land based contemporary, the HT233. You can see the arrays sandwiching the main octagonal array. The top one is IFF, and the bottom panels are communication.

View attachment 57381

Here's the kicker of this array. The entire main octagonal array itself is both tracking radar, missile guidance and illumination. This radar runs on C-band and so does the missile. Long range search functions are done by separate vehicles with other radars, like the ones I posted above.

Here are examples from within the Chinese defense industry of a dual band radar that has both search, track, and missile guidance functions on the same panel. The array on top is for search, acquisition and tracking. The array on the bottom is for the missile guidance, and it too is a square or needs to be symmetrical. If you want to know, this radar vehicle is for the HQ-16.

View attachment 57379 View attachment 57380

In this case, it is the rumours chronicling the development of 346 from a few years back which stated that the arrays sandwiching the main central array are C band AESAs.

They were not stated as IFF arrays.

 

[Iron Man]

IFF isn't radar. The segments are used to send a coded message which is replied in turn by another IFF.

Fine, fine. Yes, technically IFF isn't functionally the same as a radar. Let's just say they are all T/R arrays.

Without checking the back of the array for a serpentine S-feed, or for a large box structure at the center of the array, I am not sure if this array is positively an AESA or a PESA.

You don't have to be sure. The website from which it came seems to be pretty sure, though:

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Here is an example of an AESA which seems to me to be even thinner than all of the PESA photos you have posted so far.

You cannot tell AESA or PESA from the face alone, you need to see this at the back and at the side.

Why is this radar a PESA?

You would need a larger LNA to hold a higher voltage before breakdown. That's determined by power requirement.

Its an AESA because the architecture is like this. The huge box that makes up the spine of the YLC-2 array contains modules in a serial fashion like this.

I am pretty sure the modules on the radars are huge.

To be honest, this is almost a quasi PESA because you have one module to service a whole series of receivers and transmitters within a linear element. However for it to be a true PESA, you must only have one LNA for the entire array, not one LNA per linear element.

Your single module needs to go into an assembly that looks like this. You haven't counted all the cooling equipment surrounding this, and the cables that goes at the back of this assembly.

The fact is that I have provided examples of both thin AESAs and thick PESAs. The problem for you is that you have no way to get inside the housing of those 055 bar arrays to be able to tell which is which, and unable to judge AESA vs PESA based on thickness of the housing alone.

 

[Tam]

Fine, fine. Yes, technically IFF isn't functionally the same as a radar. Let's just say they are all T/R arrays.

It means in the case of the thinner ones, the LNA itself is not on the array but somewhere in the bottom of the array right underneath the roof of the deckhouse. In the case of the IFF arrays on the 055, the LNAs. is right behind the array itself

You don't have to be sure. The website from which it came seems to be pretty sure, though:

Please, Log in or Register to view URLs content!

Here is an example of an AESA which seems to me to be even thinner than all of the PESA photos you have posted so far.

The fact is that I have provided examples of both thin AESAs and thick PESAs. The problem for you is that you have no way to get inside the housing of those 055 bar arrays to be able to tell which is which, and unable to judge AESA vs PESA based on thickness of the housing alone.

Oh wait. You do realize that the PESAs and AESAs you shown are not phase arrays, right? .How can a PESA and an AESA not be a phase array?

That's because PESA and AESA only stands for Electronically Steering Arrays. Not all ESAs are phase arrays. There are other ways that arrays can electronically steer. There is no phase shifters used here. That's why they look thin, they comprise of a planar array with linear elements.



And that is why it looks like this. And not like this.



The one on the left is a true phase array. The one on the right is not a phase array. Both are PESAs however.

I am referring to AESAs that are planar arrays that scan only in elevation. The way they do it is that every linear element has a slight delay in the feed that causes a slight change in the emitter frequency of each linear element. This results in a phenomena called frequency steer. These arrays scan and steer up and down this way by frequency change, but has no ability to steer right and left, which is why they have to be mechanically rotated.

So you have arrays with only linear elements but without phase shifters.

But this is still an AESA because when you look at it, note the how the center of it is thick. That's where the modules that support each linear element are housed. In this array, you can see through it just like the one on top, and you can see its back.


This is another frequency steering array, like the array on top, it is not a phase array per but it is still a PESA







Unlike TPS-59 which has the modules on the center of the array, SPS-48 does not have any modules on the back of the array. You can also see that SPS-48 also has a serpentine line feed on the side that feeds every linear element with a sequential slight delay, causing a slight change in each frequency emitted on each linear element. The frequency change causes the radiating pattern to steer up and down. If you go back to the second picture of this post, you can see the radar on the right of the Tombstone phase array also has its line feed on the side of the array. These arrays only scan by elevation by frequency steering and has to be mechanically rotated for horizontal scanning.

In the case of the AESA doing frequency steer, each module feeding each linear element uses a time delay from one another in a sequential manner.

That's why to tell a PESA from an AESA, you have to see what's in the side and back. And quite frankly, even YLC-2 and TPS-59 still looks thicker than SPS-48 because of the large and thick center backbone of the radar that houses all the modules.

Finally, there is one thing all these radars have in common is that all have IFF transponders at the top of the radar. The most common position for IFF is to be directly at the top of the radar, and that is why the bars on the top of the Type 346B on the 055 should be IFF. The next common position would be at the bottom of the radar like on the Tombstone there. There are exceptions to this like when you have ring shaped IFF however.