数字音频信号信噪比的提高

To Improving the Signal-to-Noise Ratio ofDigital Audio Signal

影响数字声频质量的主要因素之一是量化噪声。本上讨论了采用过取样和噪声成形等方法，来降低数字音频信号中的量化噪声，这些方法还可使料以低通滤波器大大简化，此外，采用低比特数再量化，可以降低模数变换器及数模变换器的价格。

The quantizing noise is an important factor which influences the quality of digital audio. This paper deals with the oversampling and noise shaping which can reduce the noise and improve the signal-to-noise ratio. With these techniques,the analogous low pass fliter can be greatlysimplified,and the low bit transformation can be used to lower the cost of A/D and D/A convertors.