There are preliminary theories that need to be understood before detailing WAN specifics. One thing that is germane to communication is how bitrate affects transmission power, which in turn affects range. There are limits to the integrity of data and bitrates, as we will learn. Additionally, we need to classify narrowband versus wideband communication.
Bitrate limits and the Shannon-Hartley theorem
In long-range communication and short-range communication, the goal is to maximize bitrate and distance within the constraints of spectrum and noise. The Shannon-Hartley theorem is composed of work from Claude Shannon of MIT in the 1940s (C. E. Shannon (1949/1998). The Mathematical Theory of Communication. Urbana, IL: University of Illinois Press) and Ralph Hartley from Bell Labs in the 1920s (R. V. L. Hartley (July 1928). "Transmission of Information" (PDF). Bell System Technical Journal). Foundational work was developed by Harry Nyquist,...