Despite the availability of newer editions, the 4th edition of Proakis and Manolakis continues to be highly respected and used. Compared to the 5th edition, the 4th edition is often noted for providing a more foundational and thorough treatment of DSP basics. It is considered "a rigorous, wide-ranging treatment of modern DSP theory and practice — from z-transforms and FFT algorithms to filter design and statistical signal analysis".
: Delves into rational Z-transforms, inversion techniques, and the critical analysis of Linear Time-Invariant (LTI) systems within the Z-domain. digital signal processing proakis 4th edition pdfrar