Normal mode rejection device and normal mode rejection manner

摘要

PPROBLEM TO BE SOLVED: To generate a prediction signal on the basis of an accurate noise signal, and to properly negate noise from the outside. PSOLUTION: A noise elimination apparatus includes: a microphone 110 collecting a sound in a box body and generating a sound-collecting signal; a loudspeaker 132 for output of a regenerative signal; and a corrector 116 correcting the regenerative signal by the same transfer characteristics as those of a transmission line. The noise eliminator further includes: a regeneration eliminator 118 eliminating the corrected regenerative signal from the sound-collecting signal; a filter 124 functioning as a plurality of filters having the different number of taps eliminating a high-frequency component higher than or equal to a specified frequency from the sound-collecting signal eliminating the regenerative signal; and a prediction-signal generator 122 generating the prediction signal on the basis of the sound-collecting signal eliminating the high-frequency component. The noise eliminator further includes: a prediction-signal inverter 126 inverting the prediction signal; and an adder 128 adding the inverted prediction signal to a fundamental-sound signal input from the outside and generating the regenerative signal. PCOPYRIGHT: (C)2011,JPO&INPIT