File:Hall2006 Resolution.png

Summary
Resolving two signals. (a) A 64 ms signal sampled at 1000 Hz with a frequency sample spacing of 1/0.064 = 15.6 Hz. The signal consists of a 32 Hz and a 63 Hz sine wave, with a Hann window applied. (b) The spectrum does not resolve the two frequencies. (c) A 32 Hz with a 65 Hz signal, also with a Hann window. (d) The signals are more than twice the frequency sample spacing apart and are resolved.