CHAPTER 9 Adaptive Filters Goal of an adaptive filter: To "find and track"the optimum filter obtained by using the knowledge of signal statistics. Why to find?How to track?
CHAPTER 9 Adaptive Filters Goal of an adaptive filter: To “find and track” the optimum filter obtained by using the knowledge of signal statistics. Why to find? How to track?
Contents 9.1 Typical Applications of Adaptive Filters 9.2 Principles of Adaptive Filters 9.3 Method of Steepest Descent 9.4 Least-Mean-Square Adaptive Filters 9.5 Recursive Least-Squares Adaptive Filters 9.6 Fast RLS Algorithms for FIR Filtering 9.7 Tracking Performance of Adaptive Algorithms 9.8 Summary
9.1 Typical Applications of Adaptive Filters 9.2 Principles of Adaptive Filters 9.3 Method of Steepest Descent 9.4 Least-Mean-Square Adaptive Filters 9.5 Recursive Least-Squares Adaptive Filters 9.6 Fast RLS Algorithms for FIR Filtering 9.7 Tracking Performance of Adaptive Algorithms 9.8 Summary Contents
9.1 Typical Applications of Adaptive Filters 9.1.1 Echo Cancelation in Communications (1)electrical or line echoes (2)acoustic echoes
(1) electrical or line echoes (2) acoustic echoes 9.1.1 Echo Cancelation in Communications 9.1 Typical Applications of Adaptive Filters
9.1.1 Echo Cancelation in Communications Four-wire connection Two-wire connection Speech from Hybrid Hybrid A B Talker Echo of 4's Talker A speech Speech B from B FIGURE 9.1 Echo generation in a long-distance telephone network
FIGURE 9.1 Echo generation in a long-distance telephone network 9.1.1 Echo Cancelation in Communications
9.1.1 Echo Cancellation in Communications The switch remains off when talker B is silent! Echo suppressor 声控开关 Control Hybrid Talker Speech B from B What if talkers A and B quarrel with each other? Voice clipping will happen! FIGURE 9.2 Principle of echo suppression
FIGURE 9.2 Principle of echo suppression 9.1.1 Echo Cancellation in Communications 声控开关 The switch remains off when talker B is silent! What if talkers A and B quarrel with each other? Voice clipping will happen!