4 DSP
4.6.4 NR1 (Spectral Subtraction Method) (AF Processing)
Unlike the conventional noise reduction methods, the spectral subtraction method of NR1 is a brand new approach of noise reduction developed for the
This method was developed with a focus on improving the intelligibility of a weak SSB signal. Compared with conventional NR1 (based on a line enhancer), audio output with minimized degradation of audio quality, while
Figure
The new spectral
Note, however, since the noise estimation process of the spectral subtraction NR1 identifies any steady sound as a noise component, beat interference or a CW signal is also judged as a target of noise reduction. Meanwhile, the conventional noise reduction (based on a line enhancer) functions to emphasize beat interference or a CW signal. Because the new spectral
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