Sub-band adaptive filter structure without signal path delay for active control

This paper introduces a sub-band adaptive algorithm that avoids the signal path delay, and so can be used in an adaptive active control (feedback) system. A side effect of this algorithm is that it still causes extra delay in the error path due to the analysis filter bank. Even though the delay along the error path has only a slight influence on the steady-state behavior, it does decrease the system bounds of stability. We propose an error path delay compensation method that alleviates this problem. Simulation results are presented to illustrate the efficiency of the new adaptive algorithm.