I try to understand this question since a while and I think I came to an understanding. But I need someone to confirm it. At first, I thought the bitrate was dependent on the frequency (more sines per sec = more data per second). Now I understand that that was completely wrong.
Here is my understanding now:
Let's say I have a carrier frequency of 1000 HZ
- So my 1000 HZ frequency represents one state A.
- Now, if I have a change in that frequency (modulation) to 1001, that would be state B.
- Another change to 1002, that would be state C.
- And one more change to 1003, that would be state D.
Now let's look at the bandwidth:
- If I look at frequencies 1000 & 1001 only, I would have a bandwidth of 2, and I could represent 2 states (A and B, or 0 and 1)
- If I look at all 4 frequencies (1000-1003) I would have a bandwidth of 4, and I could represent 4 states (A, B, C, D or 00, 01, 10, 11)
So in case 1, with bandwidth of 2 I have 1 bit of information that I can carry and in case 2 I can carry 2 bit per time unit.
I know this is way to simple, but is it in the right direction?
Update: ok, I think I got something wrong. This helped me:
I just found those slides about FSK https://www.slideshare.net/jessierama/frequencyshift-keying
So in this case, with FSK there is a bitrate of 5 bps. Because the bandwidth allows to switch the states 5 times per second. When I have a higher bandwidth, I can switch more often (faster) the states, so I have more bits per second. Is that assumption right?