Hi all: Why is it that we have a dozen or so different electromagnetic wave types and yet every one of them can be used for analog and digital communication?
Thanks!
In: Physics
The “dozen or so different electromagnetic wave types” are still, ultimately, just that: electromagnetic waves. They’re all fundamentally the exact same thing, all travelling at the same speed (light), they just have different wavelengths/frequencies (wavelength and frequency are inversely proportional).
Electromagnetic waves are great for communications purposes because you’re not reliant on a physical medium to propagate the waves. They’re wireless!
Higher-frequency waves—from the top of the range of ultraviolet, up to gamma rays—are capable of ionizing atoms, which presents a risk to organic life. As such, we don’t use them for telecommunications. The lower-frequency parts of the spectrum we use for telecommunications, and we’ve carved them up into frequency bands for regulatory purposes, so that everybody can use them. The principles of how they can be used for telecommunications don’t differ though because, again: they’re all just electromagnetic waves. The principles in tuning into AM radio vs. microwave TV are essentially the same, you’re just “listening” to different frequencies of waves. (This is an extremely simplified summary; the intricacies of how an AM radio receiver and a television work are obviously very different in many ways.)
Latest Answers