Error path transfer function modelling in active noise cancellation

摘要

A signal containing the full range of frequencies to be cancelled is employed in establishing an initial estimate of the error path loss in an active noise cancellation system. The signal is from about 80 cycles per second to about 500 cycles per second and sounds like a "chirp". The estimate is in the form of coefficients used in the adaptive filter (13) of the algorithm (15) used in generating the cancelling signal.