Page 7 - DSP Integrated Circuits

vi Contents

4.15 Wave-Flow Building Blocks 144
4.15.1 Circuit Elements 145
4.15.2 Interconnection Networks 146
4.16 Design of Wave Digital Filters 150
4.16.1 Feldtkeller's Equation 151
4.16.2 Sensitivity 153
4.17 Ladder Wave Digital Filters 153
4.18 Lattice Wave Digital Filters 154
4.19 Bireciprocal Lattice Wave Digital Filters 162
4.20 Multirate Systems 166
4.21 Interpolation With an Integer Factor L 166
4.21.1 Interpolation Using FIR Filters 169
4.21.2 Interpolation Using Wave Digital Filters 172
4.22 Decimation With A Factor M 174
4.22.1 HSP43220™ 175
4.23 Sampling Rate Change With a Ratio L/M 176
4.24 Multirate Filters 177
4.25 Interpolator—Case Study 3 177

5 Finite Word Length Effects 187
5.1 Introduction 187
5.2 Parasitic Oscillations 188
5.2.1 Zero-Input Oscillations 189
5.2.2 Overflow Oscillations 191
5.2.3 Periodic Input Oscillations 193
5.2.4 Nonobservable Oscillations 193
5.2.5 Parasitic Oscillations In Algorithms Using Floating-Point
Arithmetic 194
5.3 Stability 195
5.4 Quantization In WDFs 195
5.5 Scaling of Signal Levels 198
5.5.1 Safe Scaling 199
5.5.2 FFT Scaling 201
5.5.3 Lp-Norms 201
5.5.4 Scaling of Wide-Band Signals 203
5.5.5 Scaling of Narrow Band Signals 206
5.6 Round-Off Noise 207
5.6.1 FFT Round-Off Noise 210
5.6.2 Error Spectrum Shaping 212
5.7 Measuring Round-Off Noise 213
5.8 Coefficient Sensitivity 215
5.8.1 Coefficient Word Length 216
5.9 Sensitivity and Noise 216