ELI5: Explain Like I'm 5

Active electronically scanned array

Okay kiddo, imagine drawing pictures with a laser pointer. You can move the laser pointer around to draw different shapes. An Active Electronically Scanned Array (AESA) does something similar, but instead of a laser pointer, it uses a bunch of tiny antennas that can create and direct radio waves.

These antennas are all connected to a computer and can rapidly switch on and off and change direction very quickly. The computer can control each antenna individually to make it send out radio waves in different directions or focus them all in one spot.

This lets AESA systems scan the sky like a lighthouse, sending out waves in all directions and listening for echoes that bounce back. By analyzing these echoes, an AESA can "see" all sorts of things, like planes or ships.

It's like having a bunch of laser pointers all pointed in different directions, but instead of drawing pictures, they're sending out radio waves that help us "see" what's around us. Pretty cool, huh?