| 摘要 |
The subject of the invention is a signal cleaning procedure to isolate audio-frequency signals from the background noise. During the procedure, the signal to be cleaned is led into a filter bank and the signals separated into sub-bands will be sent into a transformer unit where a transformation will be performed upon them and this way a cleaned signal will be produced. It is a typical feature of the procedure that the instantaneous amplitude or the approximated value of the amplitude of the signal of each sub-band appearing at the output (1a) of the filter bank (1) is produced first in the transformer unit, then the instantaneous amplitude values produced this way will be averaged and the signals of the sub-bands will be weighted using the averages, and finally the weighted signals will be summed up and the cleaned signal will be determined this way. |
