Contents ix 5.2 Random Processes:Basic Concepts 209 5.2.1 StatisticalAverages,212 5.2.2 Wide-Sense Stationary Processes,215 5.2.3 Multiple Random Processes,217 5.2.4 Random Processes and Linear Systems,218 5.2.5 Power Spectral Density of Stationary Processes,220 5.2.6 Power Spectral Densiry of a Sum Process,225 5.3 Gaussian and White Processes 226 5.3.1 Gaussian Processes,226 5.3.2 White Processes,228 5.3.3 Filtered Noise Processes,230 5.4 Summary and Further Reading 235 Problems 236 EFFECT OF NOISE ON ANALOG COMMUNICATION SYSTEMS 255 6.1 Effect of Noise on Amplitude Modulation Systems 255 6.1.1 Effect of Noise on a Baseband System,256 6.1.2 Effect of Noise on DSB-SC AM,256 6.1.3 Effect of Noise on SSB AM,258 6.1.4 Effect of Noise on Conventional AM,259 6.2 Effect of Noise on Angle Modulation 263 6.2.I Threshold Effect in Angle Modulation,271 6.2.2 Preemphasis and Deemphasis Filtering for FM,274 6.3 Comparison of Analog-Modulation Systems 277 6.4 Effects of Transmission Losses and Noise in Analog Communication Systems 278 6.4.1 Characterization of Thermal Noise Sources,279 6.4.2 Effective Noise Temperature and Noise Figure,280 6.4.3 Transmission Losses,283 6.4.4 Repeaters for Signal Transmission,284 6.5 Summary and Further Reading 287 Problems 288 ANALOG-TO-DIGITAL CONVERSION 296 7.1 Sampling of Signals and Signal Reconstruction from Samples 297 7.1.1 The Sampling Theorem,297 7.2 Quantization 301 7.2.1 Scalar Quantization,302 7.2.2 Vector Quantization,309Contents 6 7 5.2 Random Processes: Basic Concepts 209 5.2.l Stalistical Averages, 212 5.2.2 Wide-Sense Stationary Processes, 215 5.2.3 Multiple Rando111 Processes, 217 5.2.4 Ra11don1 Processes and linear Syste111s, 218 5.2.5 Power Spectral Densily of Stationa1y P1vcesses, 220 5.2.6 Power Spectral Density of a Su111 P1vcess, 225 5.3 Gaussian and White Processes 226 5.3.1 Gaussian Processes, 226 5.3.2 White P1vcesses, 228 5.3.3 Filtered Noise Processes, 230 5.4 Summary and Further Reading 235 Problems 236 EFFECT OF NOISE ON ANALOG COMMUN/CATION SYSTEMS 6.1 Effect of Noise on Amplitude Modulation Systems 255 6.1.1 Effect of Noise on a Baseband Systen1, 256 6.1.2 Effect of Noise oil DSB-SC AM, 256 6.1.3 Effect of Noise Oil SSB AM, 258 6.1.4 Effect of Noise 011 Conventional AM, 259 6.2 Effect of Noise on Angle Modulation 263 6.2. 1 Threshold Effect in Angle Modulation, 271 6.2.2 Preen1phasis and Dee111phasis Filtering for FM, 274 6.3 Comparison of Analog-Modulation Systems 277 6.4 Effects of Transmission Losses and Noise in Analog Communication Systems 278 6.4.1 Characterization ofThennal Noise Sources, 279 6.4.2 Effective Noise Ten1perature and Noise Figure, 280 6.4.3 Ttansnzission losses, 283 6.4.4 Repeaters for Signal Trans111issio11, 284 6.5 Summary and Further Reading 287 Problems 288 ANALOG-TO-DIGITAL CONVERSION 7.1 Sampling of Signals and Signal Reconstruction from Samples 297 7.1.1 The Sa111pli11g Theore111, 297 7.2 Quantization 301 7.2.1 Scalar Quantization, 302 7.2.2 Vector Quantization, 309 ix 255 296