Those 'transmitters' are clustered so they effectively operate as a single amplifier. And besides, all phase arrays operate within a narrow band anyway because of the fixed spacing of the elements. Too high a frequency, you get grating lobes, too low, you get mutual coupling.
052C/052D Class Destroyers
- Thread starter Jeff Head
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Those 'transmitters' are clustered so they effectively operate as a single amplifier. And besides, all phase arrays operate within a narrow band anyway because of the fixed spacing of the elements. Too high a frequency, you get grating lobes, too low, you get mutual coupling.
If your AESA can't do this its not an AESA LOL.
The whole point of transmitting at different frquencies is to be able to form a sharper more focused beam for better detection. This is basic mathematics for anyone who understands fourier series. Here is a paper: and a attached pretty picture for those who cannot be bothered to read.
SPY-1A has 8 transmitters for 4 four radar faces: Contrast this with the smaller SPY-1D, which is expicitly stated to have:
"SPY-1D The SPY-1D was the first SPY-1 radar developed for Aegis destroyers. This variant is similar to the 1B version, however, one transmitter is used by the 1D to drive all four radar faces, which are all located on a single deckhouse."
It does not have seperate transmitters to be able to transmit at 8 frequencies at once.[/QUOTE]
Whoops, forgot photo..
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Given the ship has a new Type 520 VHS AESA, it makes it moot to further upgrade the Type 346A radar for a while.
There are ways I can see how a 052D can be upgraded. For example, one way I imagine would be replacing the forward mast with an integrated mast. The Type 344, 364 and 366 radars currently on this location can be replaced by a single set of four arrays of X-band AESA like that seen on the Type 055 using a similarly designed integrated mast.
Another way, cheaper, is to replace the Type 364 radar on top with its dual sided AESA replacement first seen on the Type 075.
That's where I see the ship actually needs to improve. To reduce its RCS profile by incorporating an integrated mast. The second is to have a more capable, 3D scanning AESA radar high up a mast that can scan with an extended radar horizon against low flying stealthier targets. The current Type 364 radar being used in the high location is capable but obsolete being an old school 2D parabolic radar, which is why a replacement has been in the works since 2011. Either way with the dual sided AESA rotating radar, or having a fixed set of X-band AESA, that's miles of improvement over the Type 364.
In the future, there are ways to improve the Type 346A radar without increasing its power usage, and that is to improve the receiving gain of the array by raising its sensitivity.
You can also go into other minor but still important things like adding LPI navigation radars, improving CEC and EW.
MRBMs do not have the flight profile of hypersonic atmospheric skimming targets. MRBMs fly ballistically, they go up and they go down. That's easy to draw. Hypersonics on the other hand, fly in the region between space and the atmosphere, the exact region where a spacecraft that reentry would burn up due to its speed. Because a hypersonic flies lower than a ballistic missile, it will only be detectable once it appears on the radar horizon, which is much shorter in range than a ballistic missile.
The second problem is that no SAM can fly fast enough, and no ABM missile can operate within that range without burning up. The hypersonic vehicle is designed to withstand extremely high temperatures --- its built like a reentry vehicle. Even if you manage to get a SAM flying at this extreme speed without burning up, the hypersonic vehicle has to travel with an oscillating movement, that's why you see in charts, it travels in a wavelike movement. That's due to the lift against its body, so it rises, then dives down, rises, then dives. The movement makes it harder to intercept.
To achieve that, that's not for the radar, that's for having a missile that can do this.
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Type 051 is gone, but checking the radars and communications of the last two ships, they are fairly up to date using many of the ubiquitious radars and communications used with the other ships. The only difference is that the EW is outdated on the last two 051 (165 Zhanjiang and 166 Zhuhai). Its likely the purpose of retaining the old ships is that they are being used to train new crews in the use of currently employed equipment in the PLAN.
For that matter, you see the same with the Type 052 and 053H3 refits. Both ship refits for example, have the modern version Type 517M used with the 052C and 052D. Incidentally, the last two 051 also have this. Not only can the ships be used to train people to use this radar, they can act as radar picket ships themselves. Given the other equipment on these ships, they are standard with the rest of the PLAN fleet and can be used to train crews. Another thing is that these old ships have their EW up to date with the 052D, the carriers and the 075.
When you get to the 052B, 051B, the Sovs, these ships give you the option of using 8 or 16 YJ-12 missiles, and that's is some nasty teeth. The refits on the Sovs and the 051B also brings their EW capabilities up to date.
The LOL is on you.
That paper says nothing about transmitting at different frequencies. Neither does the image you posted. I think you confused phase shift with frequency. AESA is not different than PESA in this regard: they both use phase shift in individual array elements to steer the radar beam.
Can you quote your source, please?
My source is World Naval Weapon Systems, Norman Friedman, 5th ed. Speaking of SPY-1A on Ticonderoga: "The transmitting arrays are driven by 8 transmitters (32 CFAs, each producing 132kW peak power).
Here is another interesting piece of information on SPY-1A:
"The transmitter concept called for parallel operation of multiple crossed-field amplifiers. As part of the transmitter development, APL developed the concept of an array of subarrays in which a subarray, say 64 elements, was fed by a high-power microwave tube during transmission. By using dozens of tubes, very high power levels were achieved even though the extremely high power levels of conventional high-power radar transmitters were not present anywhere in the system. In addition, the large number of tubes provided redundancy since the loss of one or two tubes caused modest degradation. The antenna and transmitter concepts developed with AMFAR were incorporated into the SPY-1A system." Source: The Johns Hopkins University Applied Physics Laboratory. Link to paper:
If you want to defend against ballistic missiles you have little choice but emit at high power. However, depending on circumstances you could rely on a different asset for early warning, and only switch to high power mode when it is necessary to engage the threat.
A short video illustrating NATO networked BMD in Europe:
When functioning as a receveir, a larger antenna is superior to a smaller one, so there would be benefits even in LPI mode. Let's not forget that LPI isn't without drawbacks. You trade radar performance for stealth.
That's not by definition true. The radar either has this capability or it doesn't. SPY-1 required a physical upgrade to support BMD.
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So which other asset has to have BMD level radar to do that early warning?
To defend yourself against ballistic missiles you better have both long range, which is the advantage provided by longer frequency radar, and angular resolution for precise tracking, which is the advantage provided by high frequency radar. Radars however, tend to lean on one or the other due to physics. You have to have large arrays coupled with higher frequency. To offset the loss of range due to the higher frequency, you have to boost the power or have larger arrays with more elements or both. IMO, the Type 346A/B radars could provide a suitable foundation to work from.
Even then, the radar cannot command guide a missile entirely to its target. At some point the missile has to take over, use its own guidance systems to complete the flight, and it needs to be a kinetic kill, so it has to be made for this purpose.
A larger radar is still hobbled by its low radar horizon, and the larger aperture doesn't matter if it can't see below the radar horizon. That's why its a better idea as upgrade to have an integrated mast with a secondary radar, preferably AESA, that can peer down the radar horizon to spot low flying targets. Currently the IIA upgrade and the Flight III has to rely on SPQ-9B, which is a small dual sided planar or PESA (I'm not sure of which).
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Oh, and how is that relevant to say, trying to protect a US aircraft carrier in the South China Seas from DF-17 missiles? Can the AN/TPY-2 float?