The invention discloses a voice
signal bandwidth expansion method and a device thereof. The method comprises the following steps: (1) carrying out sampling rate conversion
processing on a voice
signal and obtaining a
high frequency signal and a
low frequency signal after filtering, (2) estimating
high frequency signal energy and obtaining a
high frequency signal energy value, (3) when the high frequency signal energy value is larger than a preset energy threshold, judging the voice signal as a
broadband voice signal, carrying out
gain or attenuation adjustment on the high frequency signal, and overlapping the
low frequency signal with the adjusted high frequency signal for outputting, (4) when the high frequency signal energy value is smaller than or equal to a preset energy threshold, judging the voice signal as a
narrowband voice signal, carrying out
bandwidth expansion on the
low frequency signal, obtaining a
bandwidth expansion high frequency component, and overlapping the low frequency signal with the bandwidth expansion high frequency component for outputting. According to the method and the device, the bandwidth expansion
processing mode is adjusted adaptively, the bandwidth expansion
processing is carried out on the
narrowband voice signal, the voice quality is improved, the
broadband voice signal is outputted directly, the wrong expansion of the
broadband voice signal is avoided, and the voice quality is ensured further.