Ch. 1 Introduction to filters and filter design software 1 Ch. 2 Analog filter approximation functions 15 Ch. 3 Analog lowpass, highpass, bandpass, and bandstop filters 55 Ch. 4 Analog filter implementation using active filters 85 Ch. 5 Introduction of discrete-time systems 115 Ch. 6 Infinite impulse response digital filter design 141 Ch. 7 Finite impulse response digital filter design 161 Ch. 8 Digital filter implementation using C 187 Ch. 9 Digital filtering using the FFT 209 App Technical references 227 App Filter design software and C code 229 App Filter design using C 231 App C code for normalized approximation functions 233 App C code for unnormalized approximation functions 239 App C code for active filter implementation 247 App C code for IIR filter design 253 App C code for FIR filter design 257 App Filtering sound files 259