| 摘要 |
PURPOSE: To improve system performance by reducing a modeling range from the cut-off frequency of an input signal. CONSTITUTION: This device has a model input 40 from an input microphone or a transducer 42 and an error input 44 from an error microphone or a transducer 46 and is modeled by an adaptive filter model 38 for outputting a correct signal to an omnidirectional speaker or a transducer toward 48 for supplying cancel sonic waves, so that an error signal at the error input 44 can get closer to a prescribed value, such as '0'. The input signal is high-pass filtered by a high-pass filter 62 to the cut-off frequency of 4.5Hz. The cutoff frequency of a highpass filter 56 is kept at 45Hz. Thus, an adaptive modeling process for modeling the invertion of a plant and an input filter is further improxzed. |
