Robust transmission mode
    4.
    发明授权
    Robust transmission mode 有权
    稳健的传输模式

    公开(公告)号:US06278685B1

    公开(公告)日:2001-08-21

    申请号:US09377131

    申请日:1999-08-19

    IPC分类号: H04J1100

    摘要: An interleaving/de-interleaving scheme for providing redundancy with both time and frequency diversity to data in OFDM symbols in a data transmission system. On the transmit side, encoded data to be modulated onto carriers in OFDM symbols is interleaved by storing the encoded data in an interleaver memory and reading multiple copies of the encoded data from the interleaver memory so that the encoded data copies are spread in time on non-consecutive symbols and in frequency on non-adjacent carriers. On the receive side, the multiple copies of the OFDM data are received, and phase noise computations are used to combine the multiple copies (in either metric or phase angle form) into one. From the combined copies a single metric value to be used in decoding the OFDM data is produced.

    摘要翻译: 一种用于向数据传输系统中的OFDM符号中的数据提供时间和频率分集的冗余的交织/解交织方案。 在发送侧,通过将编码数据存储在交织器存储器中并从交织器存储器中读取编码数据的多个副本来交织编码数据,以便编码的数据副本在非OFDM码元中以时间方式传播, - 不相邻载波上的连续符号和频率。 在接收侧,接收OFDM数据的多个副本,并且使用相位噪声计算将多个副本(以度量或相位角形式)组合成一个。 从组合副本中,产生用于解码OFDM数据的单个度量值。

    Enhanced channel estimation
    5.
    发明授权
    Enhanced channel estimation 有权
    增强信道估计

    公开(公告)号:US06442129B1

    公开(公告)日:2002-08-27

    申请号:US09455110

    申请日:1999-12-06

    IPC分类号: H04J900

    CPC分类号: H04L27/2608

    摘要: A scheme for identifying usable carriers for a particular modulation type and selecting, if possible, a modulation type for modulation of OFDM symbol block associated with data packets in a standard transmission mode based on data channel conditions. Channel estimation for an OFDM symbol block received by a receiving network node over a data channel during a packet transmission by a transmitting network node generates information indicative of noise events on symbols and carriers in the OFDM block, the generated information being related to modulation types available for the standard transmission mode, and determines from the generated information if at least one of the modulation types available for the standard transmission mode may be used for a next data transmission over the data channel by the transmitting network node using the standard transmission mode. One of the modulation types is selected if it is determined that at least one of the modulation types may be used. A channel map identifying good carriers for the selected modulation type is produced and stored in memory. If it is determined that one of the modulation modes for the standard transmission mode may not be selected, then a robust transmission mode is chosen instead. The robust transmission mode transmits more reliably (albeit at a lower data rate) than the standard transmission mode. The channel map associated with the standard transmission mode,if produced, or the selection of the robust transmission mode is conveyed to the transmitting network node.

    摘要翻译: 用于识别用于特定调制类型的可用载波的方案,并且如果可能,则基于数据信道条件选择用于以标准传输模式调制与数据分组相关联的OFDM符号块的调制类型。 在发送网络节点的分组传输期间由接收网络节点通过数据信道接收的OFDM符号块的信道估计产生指示OFDM块中的符号和载波上的噪声事件的信息,所生成的信息与可用的调制类型相关 并且根据所生成的信息确定可用于标准传输模式的调制类型中的至少一个可以被发送网络节点使用标准传输模式通过数据信道进行下一次数据传输。 如果确定可以使用至少一种调制类型,则选择调制类型之一。 产生识别用于所选择的调制类型的良好载波的频道映射并将其存储在存储器中。 如果确定可能不选择用于标准传输模式的调制模式之一,则选择鲁棒的传输模式。 鲁棒的传输模式比标准传输模式更可靠地发送(尽管数据速率较低)。 与标准传输模式相关联的信道映射(如果产生)或鲁棒传输模式的选择被传送到发射网络节点。