Relating phase difference in a signal with its frequency I have a 134 point complex signal. Using MATLAB, I have observed that the phase difference between any two adjacent samples of this signal is 2 radians i.e. the phase increases linearly from 0 to 268 radians over 134 samples.

How can I relate this phase difference between adjacent samples with the frequency of the same signal?

PS I am sampling at 422 Hz.
Frequency is the derivative of phase over time.

So, what's the time between two adjacent samples? That directly gives you the frequency.