I have a signal $X$ and I want to find signal $Y$ in $X$, I can achieve this by cross-correlation. Signal $X$ is sampled at $8000\textrm{ Hz}$, and $Y$ signal is sampled at $44100\textrm{ Hz}$.
My question is "should both signals be sampled at same rate to correlate to find $Y$ in $X$ " Or is it okay to correlate two signals sampled at different rate to find $Y$ in $X$?