I have been looking into the eternal fight in between RF missiles and Fighters ‘s ECMs .

There is a lot of infos on the open Net , including some rather interesting studies but the problem is to find enough data on the latest ECCM techniques used by missiles like Amraam , Mica , R-77 .

These missiles are all using some kind of mono-static multipulse radar .

Latest ECMs must use some kind of Digital Radio Frequency Memory (DRFM) techniques to try to fool the incoming missile(s) .

From the Net :

http://img607.imageshack.us/img607/5578/phaseshift.jpg

Of course , the defender must first detect the missile ‘s radar but this is not a problem nowadays if the RWR is up to speed .
When the missile goes “active” , the fight missile-ECM begins .
Missiles like late Amraams and Mica are using some very clever tricks (ECCM) to try to “resist” the deceptive jamming , but how ?

Here , I wanted to explain by myself how it is done until I found an excellent post from a guy called Gambit . Since his explainations are tip top , I decided to copy/paste what he said . If he ‘s reading , I thank him 🙂
Here is what he said :

(Thank you again Mr. Gambit)
Now , the DRFM capabilities have increased tenfold the past 10 years to the point that missiles have very little chance against powerful ECMs .
Missile ‘s radar usualy use the X band (8-12 Ghz) , very few are using K (12-18 Ghz) , Ka (18-24 Ghz) or even Ku (24-40 Ghz) bands .
(it is the reason why ECM suite like Spectra are going up to 40 Ghz) .

It has been said that some ECM suite like Typhoon ‘s Praetorian are capable to listen simultaneously the whole range of X band while sampling at up to 300-500 Mhz . Spectra sampling seems to be 500-700 Mhz .
Thalès Carbone system does even better and it seems that the sampling is up to 2 Ghz but this is classified .
Sampling rate is usualy 10 to 12 bits with a resolution comprised in between 2 and 0.5 nanoseconds (!) with Up to 4 independent and coordinated range, Doppler, amplitude target returns per DRFM channel .
What I don ‘t know is how many DRFM channels are used in systems like Praetorian and Spectra . Since Spectra is using multiple Bragg cells channelizers which are even faster because it is optical devices and it uses less filtering (more efficient) , it is even harder to guess how fast the system can duplicate the pulse-train and how many pulse-trains can be treated simultaneously .

More I think about it , more I think that missile ‘s radars are easy fooled by such ECM suites .
So , RF (EM) missiles should have a very low pk .
This is the reason why medium to long range IR missile (Mica) are probably the best way to deal with top range fighters , especialy stealthy ones .

As I said many times , it is not because a EM missile has been fired that the target will get destroyed . Even a salvo of said missiles can be fooled .

What do you think ?

Cheers .

Interesting post Bluewings, thanks.

Do you have a link to Gambit’s original post?