Low-complexity DMT transceiver
    6.
    发明授权
    Low-complexity DMT transceiver 失效
    低复杂度DMT收发器

    公开(公告)号:US06771695B1

    公开(公告)日:2004-08-03

    申请号:US09364411

    申请日:1999-07-30

    IPC分类号: H04B138

    CPC分类号: H04L25/05 H04L27/2608

    摘要: A DMT signal conforming to a first DMT standard (e.g., the full-rate G.dmt standard based on 255 tones) is sampled at a sampling rate for the first DMT standard, filtered to attenuate a subset of the tones of the first DMT standard (e.g., all G.dmt tones above tone #127), and subsampled (e.g., 2:1) to provide a subsampled, filtered signal that can be further processed using components designed to operate under a second, different DMT standard (e.g., the half-rate G.lite standard based on 127 tones). As such, a conventional half-rate G.lite DMT transceiver can be modified (e.g., by changing the downstream sampling rate from 1.104 MHz to 2.208 MHz and adding an appropriate low-pass filter and decimator) for configuration in a full-rate G.dmt DMT system. The filtering and subsampling ensure that a downstream signal (even if it is a full-rate DMT initialization or synchronization signal containing tones above tone #127) can successfully be further processed using conventional half-rate DMT transceiver components, which are less complex and less expensive than those of full-rate DMT transceivers, thereby enabling the use of relatively inexpensive consumer personal equipment (CPE) in existing distributed full-rate DMT telecommunications systems.

    摘要翻译: 符合第一DMT标准(例如,基于255个音调的全速率G.dmt标准)的DMT信号以对于第一DMT标准的采样率进行采样,被滤波以衰减第一DMT标准的音调的子集 (例如,音调#127之上的所有G.dmt音调),并且被二次采样(例如,2:1)以提供可以使用被设计为在第二种不同DMT标准下操作的组件进一步处理的子采样滤波信号(例如, 基于127个音调的半速率G.lite标准)。 因此,传统的半速率G.lite DMT收发器可以被修改(例如,通过将下行采样率从1.104MHz改变到2.208MHz并添加适当的低通滤波器和抽取器)来配置全速率G .dmt DMT系统。 滤波和二次采样确保下行信号(即使是全速率DMT初始化或包含音调#127以上的音频的同步信号)也可以使用传统的半速率DMT收发器组件进行进一步处理,这些组件不太复杂和较少 比全速率DMT收发器更昂贵,从而能够在现有的分布式全速率DMT电信系统中使用相对便宜的消费者个人设备(CPE)。