TONE SIGNAL DETECTOR, TONE SIGNAL DETECTION METHOD, AND PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a tone signal detector for preventing false detection of a tone signal, and to provide a tone signal detection method and a program.;SOLUTION: Upon selection of the frequency of a tone signal, a local oscillator 13 generates a frequency signal S13 having a shift frequency f13 corresponding to the frequency of this tone signal. A frequency shifter 12 shifts a frequency of the tone signal based on the frequency signal S13 to a passband of a BPF16. A BPF 14 removes an image signal from the frequency-converted signal S12 which the frequency shifter 12 generated, and a normalizer 15 normalizes the amplitude of the signal S14. By this, even if the amplitude of the tone signal is small, the amplitude thereof is unified to a suitable magnitude. For this reason, even if there is a difference in the amplitude of the tone signal, the tone signal can be detected reliably and an false detection can be prevented.;COPYRIGHT: (C)2010,JPO&INPIT