Gessler
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I will quote something here:Can someone here explain how SPECTRA's active cancellation would work against an AESA radar? I know how active cancellation works in things like headphones, but I'm having a hard time seeing how SPECTRA would be able to react fast enough to effectively cancel out waves that travel at the speed of light. Can it effectively cancel out AESA radar waves?
"Electrons in a conductor travel very fast, but they do not travel at the speed of light. Thus, the electronic processing is not instantaneous. And thus you cannot use a full real time approach to achieve full cancellation (you would always be reacting to events with lag). But engineers know how to cheat!! A phase shift is the same thing as a time delay. To cancel the reflected signal all you have to do is calculate a good time to start emitting the exact same signal! The time you choose will be such that the two signals (reflected and yours) are 180 degrees out of phase and thus cancel one another. So their system simply needs to first analyze the incident radar signal and determine what it is, pull characteristics of it out of memory, and then do some final processing to account for attenuation of the reflected wave, doppler effect and such (the time needed for these calculations are also precalculated and used for the final phase shift). Then you start transmitting. A proper radar return is sent back while the upfront analysis is being done but after that - practically nothing. And if it shows up for a frame or two it won't really matter."
The processing power on the Rafale is continually upgraded. But whether it's enough to spoof AESA transmitters or not remains to be seen. I guess IAF will know soon enough.