| 摘要 |
PROBLEM TO BE SOLVED: To prevent erroneous detection of frequency composition signals such as DTMF signals. SOLUTION: A frequency composition signal detector of the invention includes: signal determination means for transmitting signal components of a plurality of frequency bands from inputted signals and determining the presence or absence of signals of the respective frequency bands; frequency composition signal detection means for receiving determination results of the presence or absence of signals from the signal determination means, detecting frequency composition signals by a prescribed detection condition, and outputting the detection output to the outside; and state control means for controlling the internal state of the frequency composition signal detector by an ON state, an OFF state, and an OFF reservation state of suppressing the detection output of the frequency composition signals by the frequency composition signal detection means and performing the same processing as that in the ON state for the other processing. COPYRIGHT: (C)2012,JPO&INPIT |
