# What is the equation relating maximum data transfer rates for a given EM bandwidth?

I was looking for an equation that could show the relationship between the range of frequencies of an EM wave, and its Maximum data transfer rate. I know that ranges of shorter wavelengths can have a larger bitrate/symbol rate, but could not find an equation relating the two variables.

Thanks in advance for the help.

EDIT: I refined my wording above. Also, no one answered my question over at amateur radio SE. As for the nyquist rate wiki page, I still could not find the answer I was looking for.

• The bandwidth of a given frequency is zero. – Hot Licks Jul 28 '18 at 1:32
• @HotLicks could you clarify what you mean? Did I misspeak? – FOG.js Jul 28 '18 at 1:34
• "Bandwidth" refers to the range of adjacent frequencies occupied by some signal. – Hot Licks Jul 28 '18 at 1:35
• Oh yes, but I was using the computational definition: "The maximum rate of data transfer across a given path" @HotLicks – FOG.js Jul 28 '18 at 1:36
• Right. And the way you transfer data is by varying the carrier frequency. – Hot Licks Jul 28 '18 at 1:39

$$C = B \log_2 ( 1 + S / N )$$