This is a very common question I've found by looking around, I've read many answers but they all say the same thing about sidebands: they carry the information. Or at least, in AM they do. That's what I'm actually learning about right now. Apparently the sidebands are generated around the carrier, for example a modulating signal with a frequency f1 and a carrier with f0 generate sidebands f0+/f1. As to why there's any energy at all why all you're doing is modulating the amplitude, people throw some trigonometry around, saying things like the frequencies are generated from multiplying the two cosine waves and stuff like that. Well here's the issue: when I multiply x and y, I get z, not z and x+/-y side answers. So I look up what happens when you multiply two sin functions. I found a page on here about multiplying sine waves, but the answer ended up being frequency +/- frequency again, "just because" it seems like. Maybe I need to delve deeper into the maths or something, because that isn't a very good reason. Long story short, despite all this knowledge of sidebands, I have exactly zero understanding.
My Questions:
1. Why +/-? What's significant about the sum and difference?
2. Why are two identical sidebands generated above and below? (Similar to above question)
3. Can you graph the sidebands in the way most books show AM? (A low frequency sine wave, a high frequency sine wave, and then an overlay of the two combined, with an envelope detailed around the carrier in the shape of the low frequency sine wave. You know, that old diagram).
In this picture:
4. Can you see the sidebands?
5. Are they left out?
6. Does that even make sense?
If you have to throw around maths that look like this: http://physics.stackexchange.com/qu...he-cause-of-sidebands-in-amplitude-modulation
Just tell me to "Check the maths" and save yourself some trouble, then I'll redouble my efforts to understanding what's going on there.
7. Can you analogize the sidebands? (Is analogize a word? Make me an analogy I'm trying to say).
Okay I'm done. Proper help is so appreciated, I can't articulate. Thanks.
My Questions:
1. Why +/-? What's significant about the sum and difference?
2. Why are two identical sidebands generated above and below? (Similar to above question)
3. Can you graph the sidebands in the way most books show AM? (A low frequency sine wave, a high frequency sine wave, and then an overlay of the two combined, with an envelope detailed around the carrier in the shape of the low frequency sine wave. You know, that old diagram).
In this picture:
4. Can you see the sidebands?
5. Are they left out?
6. Does that even make sense?
If you have to throw around maths that look like this: http://physics.stackexchange.com/qu...he-cause-of-sidebands-in-amplitude-modulation
Just tell me to "Check the maths" and save yourself some trouble, then I'll redouble my efforts to understanding what's going on there.
7. Can you analogize the sidebands? (Is analogize a word? Make me an analogy I'm trying to say).
Okay I'm done. Proper help is so appreciated, I can't articulate. Thanks.