I'm working on a game where the characters will carry around PDAs (personal digital assistants) and the little devices will occasionally "broadcast" info to each other. I want to create an effect that looks something like one of the above pictures. The concentric circles won't emanate from an antenna, but from the PDA itself. Ideally the lines should be very skinny, and should radiate outward from the center, fading (getting more transparent) as they go. I have tried to do this with an animated sprite I made in photoshop with an alpha channel, but it didn't look too good.

Can anybody give this a try with particles or draw_point3d(()? Thanks!