to be clear, its not specifically "for Anonymous", although the lede unwittingly allies tor devs with them. which is probably closer to the truth than was intended anyway, wait, political dissidents use it too.
rtl-sdr for the win, i can talk about this stuff all day long.
now for the software part, with windows systems, options are plenty. linux, hit and miss. gnu-radio is a lofty suite, but here for me, its gqrx.
building your own antennas can be quite fun. i typically craft something every month or so, depending on my obsession at any given time, aircraft, satellite, amateur.
i also buy commercial grade hardware., as rtl-sdrs can be a little dodgy due to low tolerace components, so weak signals are hard to digout of a sound floor with cheapo dongles.
a friend of mine did the do recently, we were all pretty pissed off, me more so cuz i flew my wife across the country for a wake, and i didnt even get my lockpicks back. anyway, they were fairly close, it really hurt her as a friend, so if you are looking to hurt someone, hurt me instead dude, i will give you my d0x and you can call me and harass me to your hearts content, and give me grief about my (1).
you do understand that flightaware data is crowdsourced, yes? the data format is trivial to fake, and subsequently upload. i am not saying thats the case here, but implicitly trusting user input makes me skeptical about the entire conclusion.
tldr: I didn't use Flightaware; I observed these aircraft directly using my own receiver, decoding their callsigns and squawk codes, and correlated with FAA records and the company confirmed by the FBI itself to be a front.
But it's true, most of this evidence is still circumstantial. Just because a company with an odd name and no internet presence has the same PO Box as the DOJ doesn't prove it's a front company; but it's pretty suggestive.