| 摘要 |
PROBLEM TO BE SOLVED: To extract the forward audio signal component from sound collection signals of omnidirectional microphones 3 and 4. SOLUTION: Microphones 3 and 4 are disposed at prescribed intervals, an output signal of the microphone 4 is delayed depending on the interval of the microphones and subtracted from an output signal of the microphone 3 to produce a signal S1 while an output signal of the microphone 3 is delayed depending on the interval of the microphones and subtracted from an output signal of the microphone 4 to produce a signal 82. The audio signals S1 and S2 are divided, respectively, into a plurality of frequency bands to obtain a pair of frequency band division signals Sr1, Sl1,..., SrN, SlN of the same frequency band. A plurality of band division signals Sc1,..., ScN obtained by selecting signal components of lower signal level from a pair of a plurality of band division signals of the same frequency band are synthesized so that the forward audio signal component can be extracted. |
