A novel method for suppressing the quantization noise based on fractional fourier transform

For the quantization noise occurs during the process of sampling and quantization in the A/D converter, a novel method based on the fractional Fourier transform was proposed to suppress the quantization noise. According to the statistical property of the classical quantizer, the quantization noise was proved to be white noise in the fractional Fourier domain. By means of oversampling and digital filtering in the fractional Fourier domain, the quantization noise of the input signal could be suppressed, and the signal quality was improved. Theoretical result and simulation show that the novel method can suppress the quantization noise effectively, and improve the output signal-to-quantization-noise ratio of the A/D converter. In addition, the novel method exhibits a better quantization noise reduction performance than the traditional method in the Fourier domain, especially when the linear frequency modulation signal is processed.