Yeah, I was hoping someone would chime in and explain. I'm honestly not quite sure. This is one of those things where all the explanations are very hand-wavey

Yeah, I was hoping someone would chime in and explain. I'm honestly not quite sure. This is one of those things where all the explanations are very hand-wavey https://en.wikipedia.org/wiki/Side-scan_sonar https://en.wikipedia.org/wiki/Side-scan_sonar "The intensity of the acoustic reflections from the seafloor of this fan-shaped beam is recorded in a series of cross-track slices. [..] Next the transducers evolved to fan-shaped beams to produce a better "sonogram" or sonar image" Okay.. but how does it actually accomplish that..? My initial guess was that it's one transmitter and then an small array of receivers (to make a phased array) - however subsequent descriptions seems to say it can be accomplished with one transceiver "The earliest side-scan sonars used a single conical-beam transducer" Maybe a synthetic aperture...? Though the descriptions don't seem to match that either - and it describes it being directly drawn on paper "The early paper records were produced with a sweeping plotter that burned the image into a scrolling paper record". I've also had zero luck trying to find the math behind synthetic apertures (radar/sonar)