首页    期刊浏览 2024年09月21日 星期六
登录注册

文章基本信息

  • 标题:Distortion-Free 1-Bit PWM Coding for Digital Audio Signals
  • 本地全文:下载
  • 作者:Andreas Floros ; John Mourjopoulos
  • 期刊名称:EURASIP Journal on Advances in Signal Processing
  • 印刷版ISSN:1687-6172
  • 电子版ISSN:1687-6180
  • 出版年度:2007
  • 卷号:2007
  • DOI:10.1155/2007/94386
  • 出版社:Hindawi Publishing Corporation
  • 摘要:

    Although uniformly sampled pulse width modulation (UPWM) represents a very efficient digital audio coding scheme for digital-to-analog conversion and full-digital amplification, it suffers from strong harmonic distortions, as opposed to benign non-harmonic artifacts present in analog PWM (naturally sampled PWM, NPWM). Complete elimination of these distortions usually requires excessive oversampling of the source PCM audio signal, which results to impractical realizations of digital PWM systems. In this paper, a description of digital PWM distortion generation mechanism is given and a novel principle for their minimization is proposed, based on a process having some similarity to the dithering principle employed in multibit signal quantization. This conditioning signal is termed “jither” and it can be applied either in the PCM amplitude or the PWM time domain. It is shown that the proposed method achieves significant decrement of the harmonic distortions, rendering digital PWM performance equivalent to that of source PCM audio, for mild oversampling (e.g., × 4 ) resulting to typical PWM clock rates of 90 MHz.

国家哲学社会科学文献中心版权所有