EW attempts to degrade the physical basis for transferring information, while cryptographic warfare works between bits and bytes. Neither type of EW is truly new. In tandem, they underlay Britain's success in defending its island against the Luftwaffe. In recent years, as information warfare has acquired a certain cachet, efforts have been made to reinvent EW under this new moniker. Offense and defense keep coming up with new techniques.
More modern radars hop from one outgoing frequency band to the next.
To counter radars, today's jammers must be able to acquire the incoming signal, determine its frequency, tune the outgoing jamming signal accordingly, and send a blur back quickly enough to minimize the length and strength of the reflected signal. Coalition forces in the Gulf developed new synergies using jamming aircraft en masse. As digitization improves, radar can acquire a target by generating a transient pulse and analyzing the return signal before a false jamming signal overwhelms the reflection. The cheaper digital manipulation becomes, the more logic favors the separation of an emitter from a collector. Emitters, the targets of antiradiation missiles, would proliferate, to ensure the survival of the system and to act as sponges for expensive missiles.