>> John Chowning refined the concept, moved from frequency to phase modulation, and brought FM into the digital realm. > ?? Chowning's paper doesn't mention ph

>> John Chowning refined the concept, moved from frequency to phase modulation, and brought FM into the digital realm. > ?? Chowning's paper doesn't mention phase modulation at all, does it? His equation is for frequency modulation. > >https://web.eecs.umich.edu/~fessler/course/100/misc/chowning https://web.eecs.umich.edu/~fessler/course/100/misc/chowning... > > I would presume that the relationships between phase and frequency modulation were known a half-century before Chowning. Chowning says his equation is for frequency modulation, but the equation is actually phase modulation. Chowning's equation(1): e = A sin(𝛼t + I sinβt) That's phase modulation. Frequency modulation would be: e = A sin((𝛼 + I sinβt) t) Very different. That's okay; it's the first academic paper on the topic, and things were still a little wobbly. After the paper, he and others refined the concept, moved from frequency to phase modulation, and built digital implementations.