"The Scientist and Engineer's Guide to Digital Signal Processing" by Steven W Smith available online here: http://www.dspguide.com/pdfbook.htm http://www.dspgui

"The Scientist and Engineer's Guide to Digital Signal Processing" by Steven W Smith available online here: http://www.dspguide.com/pdfbook.htm http://www.dspguide.com/pdfbook.htm One of my colleagues lent me a hardcover copy very good explanation I found it a huge help for a recent project I was working on (Sonic vibration sensor). Clearest explanation of everything I was able to find. Fourier transforms were covered during my engineering degree but it had been some years since I'd needed to concern myself with them. Top google hits were not really helping and I found this textbook was invaluable.