Well, the value of the stock for people who essentially do not have any meaningful control of the business must essentially be tied to the expectation of some liquidity event down the line -- future cash flows. So this could come in the form of dividends, sale of the stock, bankruptcy proceedings, or a purchase of the business.
If I knew for certain (big if) that a business would never have a liquidity event and I couldn't transfer my ownership then it's dead capital for all intents and purposes and you could consider its value essentially $0, right?
I would actually go so far to say as I am not aware of any good "as it really works" references. Handbooks exist, but they're pretty expensive.
Since you have an EE background, I would recommend a few strategies (in any order, except 0 should be first if you have major deficiencies):
0) Brush up on some of your math if you need to. Linear algebra (just up to Eigenvector/Eigenvalue), vector calculus, differential equations. Mostly just understanding the concepts is OK, because the major derivations for RF engineering are relatively simple problems. That said, RF engineering is just one big love letter to linear algebra.
1) Read Pozar, as another commenter have suggested, but you don't need to cover-to-cover it. You absolutely must know some network theory, the basics of transmission lines (characteristic impedance, propagation, loaded driving point impedance), and simple matching techniques (basic RF design is about 75% just making sure power goes where you want it to). Beyond that you can pick and choose depending precisely on what you're doing.
2) Read older papers (1940s-1980s depending on topic) on whatever you're interested in. They're going to assume relatively little starting information. The only caveats are that notation has changed and that a lot of the design techniques, while still valid, were more useful when simulators weren't readily available (i.e. they assume a really strong mathematical background).
3) Stay low frequency as much as possible early on. <6 GHz for sure, ideally lower. This makes things a lot cheaper (metrology, components) and makes mechanical tolerances less critical. Stuff just gets less "fiddly". There's of course a tradeoff where things start to get pretty big at low (10-100's MHz) frequencies.
4) Tear apart anything you can get your hands on -- broken metrology equipment for one. Try and figure out why people are doing what they're doing. Just because a system's cheap doesn't mean they aren't using some cool tricks.
Focusing in on "grabbing references", it's as easy as drag-and-drop if you use Zotero. It can copy/paste references in BibTeX format. You can even customize it through the BetterBibTeX extension.
If you're not a Zotero user, I can't recommend it enough.
To be maximally pedantic, sine waves (or complex exponentials through Euler's formula), ARE special because they're the eigenfunctions of linear time-invariant systems. For anybody reading this without a linear algebra background, this just means using sine waves often makes your math a lot less disgusting when representing a broad class of useful mathematical models.
Which to your point: You're absolutely correct that you can use a bunch of different sets of functions for your decomposition. Linear algebra just says that you might as well use the most convenient one!
If I knew for certain (big if) that a business would never have a liquidity event and I couldn't transfer my ownership then it's dead capital for all intents and purposes and you could consider its value essentially $0, right?