AESA radars: Where will industry refocus its efforts?

摘要

More and more, naval radars are active electronically scanned arrays. As their components become less expensive, they may well become dominant in the naval/maritime operational environment.Active electronic scanning is distinguished from passive scanning, which was the rule in past phased array radars such as the American SPY-1 of the Aegis system. They are now called passive electronically scanned array (PESA) radars, to distinguish them from the newer active electronically scanned arrays (AESAs).Let us begin with a technical description first. In a PESA radar, a signal generator feeds into all the individual elements in the array; computer control is exercised over the phases of the elements. Adding up the contributions of the elements with the appropriate phases forms a beam pointing in a desired direction. The computer applies different combinations of phases to create beams in different directions, and the radar appears to scan. Its great advantage over the earlier type of radar, which used a reflector to create a single beam, is that its scan is inertia-less - its beam can more instantly in any desired direction.