| 摘要 |
<P>PROBLEM TO BE SOLVED: To detect, with a little operation amount, a change in continuity between two spaces. <P>SOLUTION: A continuity detection apparatus 10 comprises a band-pass filter circuit 26 which passes a predetermined frequency band in a signal inputted from a microphone 11, a first A/D converter 27 which converts a signal passed through the band-pass filter circuit 26 into a digital form, a first high-pass filter circuit 16 which blocks the passage of a frequency lower than or equal to a predetermined value in the signal passed through the first A/D converter 27 and removes a fluctuation component in the signal, a first full-wave rectifier circuit 17 which takes an absolute value of the signal passed through the first high-pass filter circuit 16, a first nonlinear filter circuit 19 which applies nonlinear conversion processing on a waveform of the signal passed through the first full-wave rectifier circuit 17, and a determination processing unit 23 which utilizes the signal passed through the first nonlinear filter circuit 19 to investigate a value of the signal passed through the first full-wave rectifier circuit 17 and, on a condition where the signal exceeds a first threshold value, determines the presence of continuity between two spaces. <P>COPYRIGHT: (C)2012,JPO&INPIT |
