054/A FFG Thread II

[nlalyst]

I mean, seems like in essence you agree with me that the capabilities of the individual comparative systems are educated guesses at best?

A large number of platforms have their capabilities based on data available from publishers like Jane’s. Buying the game is sort of a cheap way of getting access to data that would otherwise be over 10 times more expensive.

But yeah, in many cases these numbers are educated guesses. For example, the diving depth and top speed of US nuclear submarines. Even more, sometimes they’re just a conscious balancing act: the PL-15 and Meteor have the exact same max range.

 

[by78]

Self-explanatory.

 

[nlalyst]

SPG-62 is an exception in the history of CW emitters and radars, and you cannot use this as the general example. Monostatic CW radar applications are as common as the parking radar on your car, to the radar guns police use to nail your car's speed on the highway. Another is their use as altimeters such as on helicopters.

Plus I am not talking about the SM-2. I am talking about the HQ-16, and the history back to the Buk and other Soviet SAMs. SPG-62 cannot be considered a radar as being one way.

Some FMCW radars which are monostatic. These radars track the targets on their own and illuminate them. The Square Pair radar used by the Soviets.

View attachment 76478

or the Low Blow radar.

View attachment 76480

Later you progress from having separate transmit and receive antennas, to only a single antenna simultaneously transmitting and receiving, such as the Fire Dome for the Buk, which probably led to the Front Domes.

View attachment 76487

Probably the most famous, Flap Lid or Tombstone used with the S300. And of course, you have Fire Dome used with the Buk, which probably led to Front Dome for the ships. On the Western side, those using FMCW includes the MPQ-53 for the Patriot, the Mk. 92 FCR on the OHP.

What is your source that Flap Lid is FMCW? I thought that was an ICWI system.

AFAIK, Mk. 92 FCR is a combo of PD tracking radars and a separate CWI transmitter sharing the same antenna.

My understanding was that it is a ICWI, a.k.a Pulse Doppler Illumination.

MOD: can you please move our discussion to the missile guidance thread?

 

[nlalyst]

SPG-62 is an exception in the history of CW emitters and radars, and you cannot use this as the general example. Monostatic CW radar applications are as common as the parking radar on your car, to the radar guns police use to nail your car's speed on the highway. Another is their use as altimeters such as on helicopters.

Plus I am not talking about the SM-2. I am talking about the HQ-16, and the history back to the Buk and other Soviet SAMs. SPG-62 cannot be considered a radar as being one way.

Some FMCW radars which are monostatic. These radars track the targets on their own and illuminate them. The Square Pair radar used by the Soviets.

View attachment 76478

or the Low Blow radar.

View attachment 76480

Later you progress from having separate transmit and receive antennas, to only a single antenna simultaneously transmitting and receiving, such as the Fire Dome for the Buk, which probably led to the Front Domes.

View attachment 76487

Probably the most famous, Flap Lid or Tombstone used with the S300. And of course, you have Fire Dome used with the Buk, which probably led to Front Dome for the ships. On the Western side, those using FMCW includes the MPQ-53 for the Patriot, the Mk. 92 FCR on the OHP, and the STIR, which also has its Japanese and Korean equivalents used in European, Japanese and Korean navies.

Some active guided missile seekers are monostatic CWI or FMCW applications. Enclosed is the Brimstone antitank missile and the Swedish RBS-15 antiship missile.

View attachment 76485 View attachment 76486


The FMCW radar used on Ship 892 used for missile testing. This goes back to the dual separate transmit and receive arrays.

View attachment 76488

According to Carlo Kopp, Fire Dome is not FMCW either, but a PD search and track radar combined with a CWI:
“The 9S35 Fire Dome provides a limited search and acquisition capability, a tracking capability and CW illumination for terminal guidance of the semi-active homing SAM seekers. It incorporates an IFF interrogator, optical tracker, datalink, and is powered by the TELAR's gas turbine generator. A shared antenna is employed for two X-band transmit/receive channels. These respectively provide a pulsed mode for search and track functions, with linear chirp for compression, and a CW mode for illumination. Monopulse angle tracking is employed for jam resistance. For target tracking the antenna and feed system provide a mainlobe with 2.5° width in azimuth and 1.3° in elevation. For CW illumination the antenna and feed system provide a mainlobe with 1.4° width in azimuth and 2.65° in elevation.”

If Front Dome is a derivative of Fire Dome, doesn’t this put your thesis under question? Or do you have evidence that the Chinese are using FMCW for HQ-16 guidance?

 

[Tam]

What is your source that Flap Lid is FMCW? I thought that was an ICWI system.

AFAIK, Mk. 92 FCR is a combo of PD tracking radars and a separate CWI transmitter sharing the same antenna.

My understanding was that it is a ICWI, a.k.a Pulse Doppler Illumination.

MOD: can you please move our discussion to the missile guidance thread?

Any CW system that can give range information is an FMCW by default unless it is an ICW. A pure CW system with regular sinusoidal waveform is incapable of providing range information due to the lack of pauses and markers in the wave. To get range, you need to time for the return of the echo. You cannot do that with a continuous wave because there is no beginning and no end unlike a pulse. To get range, you need to frequency modulate a marker, like a chirp or a peak into the wave. Then you measure for the time this peak is returned.

Mk. 92 FCR consists of a STIR on the top and a cosecant parabolic on the bottom. You can see the top part is actually a STIR that's been licensed. The bottom is a surface search radar with IFF.

 

[Tam]

According to Carlo Kopp, Fire Dome is not FMCW either, but a PD search and track radar combined with a CWI:
“The 9S35 Fire Dome provides a limited search and acquisition capability, a tracking capability and CW illumination for terminal guidance of the semi-active homing SAM seekers. It incorporates an IFF interrogator, optical tracker, datalink, and is powered by the TELAR's gas turbine generator. A shared antenna is employed for two X-band transmit/receive channels. These respectively provide a pulsed mode for search and track functions, with linear chirp for compression, and a CW mode for illumination. Monopulse angle tracking is employed for jam resistance. For target tracking the antenna and feed system provide a mainlobe with 2.5° width in azimuth and 1.3° in elevation. For CW illumination the antenna and feed system provide a mainlobe with 1.4° width in azimuth and 2.65° in elevation.”

If Front Dome is a derivative of Fire Dome, doesn’t this put your thesis under question? Or do you have evidence that the Chinese are using FMCW for HQ-16 guidance?

My understanding of Front Dome is that it can guide two missiles simultaneously. For such you would need two transmitters at different channels. Then there is the question of 9S35's successor, 9S36, which is a PESA if that one still uses dual transmitters, which I kind of see that difficult with a PESA. In any case, with an antenna that has two working X-band transmitters simultaneously, there is still considerable interference between the transmit and receive of the two, especially when the two are similar in frequency. FMCW can again, be called into use to improve the S/N ratio.

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FMCW is also used as a counter resistance to ECM, since by putting markers into the wave you can also code it. FMCW itself isn't needed for missile guidance which only needs to measure for rate of closure, and is not processing for range. But FMCW itself benefits for a missile in terms of ECM resistance. Otherwise its very easy to counter a CW seeker since all the jammer needs to do is duplicate the sinusoidal wave.

 

[Tam]

Self-explanatory.

First picture looks odd as the ship is missing the illuminators on top of the bridge. Due for replacement perhaps.

 

[gongolongo]

Please elaborate on what's weak.
Say, YJ-83 apparently got an update very recently.

YJ-83 short ranged and sub sonic. HQ-16 are very short ranged compared to something like SM-2 Block 3C.

Somebody did mention that these could be cheaper vessels to handle enemy forces that are not nearly as capable as the US.

 

[nlalyst]

Any CW system that can give range information is an FMCW by default unless it is an ICW. A pure CW system with regular sinusoidal waveform is incapable of providing range information due to the lack of pauses and markers in the wave. To get range, you need to time for the return of the echo. You cannot do that with a continuous wave because there is no beginning and no end unlike a pulse. To get range, you need to frequency modulate a marker, like a chirp or a peak into the wave. Then you measure for the time this peak is returned.

Mk. 92 FCR consists of a STIR on the top and a cosecant parabolic on the bottom. You can see the top part is actually a STIR that's been licensed. The bottom is a surface search radar with IFF.

View attachment 76544

Based on everything I’ve read, Flap Lid is a Pulse Doppler radar. It’s illumination mode is ICWI, which in other contexts can also be found under the name pulse doppler illumination.

The Mk. 92 FCR consists of two radars, the combined antenna system that you’ve shown and a STIR (not to be confused with the Dutch STIR!). The combined system is a pulse doppler radar with a separate CWI for illumination. The American STIR is also u monopulse tracker with a separate CWI. Take a look at this publication. There is a figure showing very clearly that both radars have separate CWI transmitters:

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[Tam]

Based on everything I’ve read, Flap Lid is a Pulse Doppler radar. It’s illumination mode is ICWI, which in other contexts can also be found under the name pulse doppler illumination.

The Mk. 92 FCR consists of two radars, the combined antenna system that you’ve shown and a STIR (not to be confused with the Dutch STIR!). The combined system is a pulse doppler radar with a separate CWI for illumination. The American STIR is also u monopulse tracker with a separate CWI. Take a look at this publication. There is a figure showing very clearly that both radars have separate CWI transmitters:

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Do you have the report that says Flap Lid is pulse doppler with ICWI? That's different from what I read. This would be interesting to read and it would be to my pleasure.

Don't confuse monopulse with pulse and pulse doppler. Monopulse means something entirely and CWI can be monopulse. What your paper states is that there is a single X-band pulse transmitter, and that's servicing one of the antennas in the combined antenna pod, which should be the parabolic antenna below with the IFF dipoles. That acts as a surface search radar. The upper antenna --- and yes, it is licensed from the Dutch STIR if you read your own paper carefully right to the end --- is a monopulse, along with the other STIR. Monopulse however doesn't mean pulse radar, rather its a way to get angle and tracking information from a single emission. Missiles such as the Sparrow, switched from conical scan to monopulse as monopulse is much more difficult to jam. Do realize that a monopulse antenna needs a horn with four feeds, which is going to be difficult to have a pulse radar that has monopulse tracking, and a CWI illuminator that sends out a monopulse signal.