Method and apparatus for channel quality measurements
    2.
    发明授权
    Method and apparatus for channel quality measurements 有权
    用于信道质量测量的方法和装置

    公开(公告)号:US08170155B2

    公开(公告)日:2012-05-01

    申请号:US12839836

    申请日:2010-07-20

    IPC分类号: H03D1/00 H04L27/06

    摘要: A method and apparatus are provided for measuring channel quality over which has been transmitted a sequence of symbols produced by encoding and constellation mapping a source data element sequence. The method includes receiving a sequence of received symbols over the channel whose quality is to be measured. The sequence of received symbols is de-mapped based on a first channel quality indicator previously transmitted to a transmitter of the sequence of symbols. The method also includes decoding the de-mapped symbols to produce a decoded output sequence. In some embodiments, the decoding may be based on the first channel quality indicator. The method also includes re-encoding the decoded output sequence to produce a re-encoded output sequence. The method also includes correlating the de-mapped symbols with the re-encoded output sequence to produce a second channel quality indicator. The second channel quality indicator is transmitted to the transmitter to adaptively select a type of mapping based on the second channel quality indicator. In some embodiments, the transmitter may adaptively select a type of encoding based on the second channel quality indicator.

    摘要翻译: 提供了一种用于测量已经发送了通过对源数据元素序列进行编码和星座映射而产生的符号序列的信道质量的方法和装置。 该方法包括在其质量要被测量的信道上接收接收到的符号序列。 基于先前发送到符号序列的发射机的第一信道质量指示符来对接收符号的序列进行解映射。 该方法还包括对解映射符号进行解码以产生解码的输出序列。 在一些实施例中,解码可以基于第一信道质量指示符。 该方法还包括对解码的输出序列进行重新编码以产生重新编码的输出序列。 该方法还包括将去映射符号与重新编码的输出序列相关联以产生第二信道质量指示符。 第二信道质量指示符被发送到发射机,以基于第二信道质量指示符自适应地选择一种类型的映射。 在一些实施例中,发射机可以基于第二信道质量指示符自适应地选择一种类型的编码。

    Virtual mimo communication system
    3.
    发明授权
    Virtual mimo communication system 有权
    虚拟mimo通信系统

    公开(公告)号:US07508798B2

    公开(公告)日:2009-03-24

    申请号:US10321999

    申请日:2002-12-16

    IPC分类号: H04Q11/00

    摘要: The present invention provides an effective way to create a virtual MIMO transmission system using mobile terminals that have only one transmit path and antenna. This is accomplished by assigning mobile terminals to a group and assigning certain shared resources and user-specific resources to those mobile terminals in the group. In a synchronized fashion, the mobile terminals will provide uplink transmission in concert, as if they were a single entity having multiple transmission paths and antennas. Preferably, the shared resources bear on how the data is transmitted, and the user-specific resources relate to pilot signals. The data transmitted may be encoded in any number of ways, and in one embodiment, the mobile terminals may relay their information to each other, such that uplink transmissions can incorporate STTD decoding or other space-time codes. The invention is applicable to virtually any multiple access technology, including OFDM, TDMA, and CDMA, preferably synchronous CDMA.

    摘要翻译: 本发明提供了使用仅具有一个发送路径和天线的移动终端来创建虚拟MIMO传输系统的有效方式。 这通过将移动终端分配给组并且向组中的那些移动终端分配特定共享资源和用户特定资源来实现。 以同步方式,移动终端将一起提供上行链路传输,好像它们是具有多个传输路径和天线的单个实体。 优选地,共享资源对数据的传输方式如何,并且用户特定的资源与导频信号有关。 传输的数据可以以任何数量的方式进行编码,并且在一个实施例中,移动终端可以将它们的信息彼此中继,使得上行链路传输可以包含STTD解码或其他时空码。 本发明可应用于几乎任何多址接入技术,包括OFDM,TDMA和CDMA,优选地是同步CDMA。

    Combined space-time decoding
    4.
    发明授权
    Combined space-time decoding 有权
    组合时空解码

    公开(公告)号:US07394860B2

    公开(公告)日:2008-07-01

    申请号:US10263268

    申请日:2002-10-02

    IPC分类号: H04B7/02 H04L1/02

    CPC分类号: H04L1/0618

    摘要: The present invention relates to decoding space time coded (STC) signals transmitted from a number of transmit antennas. First, a separate detection technique is used to determine initial decoding solutions corresponding to the symbols transmitted from each of a number of transmit antennas at a given time. For each initial solution, a limited area about the initial solution is defined. Each of the limited areas will correspond to regions including constellation points proximate the initial solution. The initial solutions are used to define a limited, multi-dimensional space. Accordingly, the initial solutions are used to reduce the search complexity associated with joint decoding by defining a limited space about the initial solutions. Finally, a joint decoding technique is implemented within the limited space to find a final solution.

    摘要翻译: 本发明涉及解码从多个发射天线发射的空时编码(STC)信号。 首先,使用单独的检测技术来确定在给定时间从与多个发射天线中的每一个发送的符号相对应的初始解码解。 对于每个初始解决方案,定义关于初始解决方案的有限区域。 每个有限区域将对应于包括邻近初始解决方案的星座点的区域。 初始解决方案用于定义有限的多维空间。 因此,初始解决方案用于通过定义关于初始解决方案的有限空间来减少与联合解码相关联的搜索复杂度。 最后,在有限的空间内实现联合解码技术,找到最终解决方案。

    Space-time transmit diversity systems and methods for ofdm applications
    5.
    发明授权
    Space-time transmit diversity systems and methods for ofdm applications 有权
    时空发射分集系统和方法应用于ddm

    公开(公告)号:US09450664B2

    公开(公告)日:2016-09-20

    申请号:US11547073

    申请日:2005-04-04

    摘要: Embodiments of the invention provide orthogonal Frequency Division Multiplexing-Space-time Block Codes (OFDMSTBC) mappings for code rate 1, 2 and 4 codes for 4 Transmit Antennas. To overcome the innate weakness of known codes, a new class of STBC codes is provided which is particularly suited for OFDM applications, although other applications are also contemplated. Codes for STBC mappings in the time direction, the frequency direction and a combined time frequency mapping for multiple antennas are provided. In OFDM applications, these codes exploit the properties of OFDM and FEC codes to substantially maintain the advantages of Alamouti codes. Furthermore, while the detailed examples given herein focus on four antenna applications, they can be easily extended to systems with more than four antennas.

    摘要翻译: 本发明的实施例为4个发射天线的码率1,2和4码提供正交频分复用 - 空时块码(OFDMSTBC)映射。 为了克服已知代码的固有缺点,提供了一类新的STBC代码,其特别适用于OFDM应用,尽管也考虑了其他应用。 提供了在时间方向上的STBC映射代码,频率方向和多个天线的组合时间频率映射。 在OFDM应用中,这些代码利用OFDM和FEC码的性质来基本上保持Alamouti码的优点。 此外,虽然本文给出的详细示例集中在四个天线应用,但是它们可以容易地扩展到具有多于四个天线的系统。

    Adaptive two-dimensional channel interpolation
    6.
    发明授权
    Adaptive two-dimensional channel interpolation 有权
    自适应二维信道插值

    公开(公告)号:US08331465B2

    公开(公告)日:2012-12-11

    申请号:US12064566

    申请日:2006-08-22

    IPC分类号: H04K1/10

    摘要: A method and apparatus for improving channel estimation within an OFDM communication system. Channel estimation in OFDM is usually performed with the aid of pilot symbols. The pilot symbols are typically spaced in time and frequency. The set of frequencies and times at which pilot symbols are inserted is referred to as a pilot pattern. In some cases, the pilot pattern is a diagonal-shaped lattice, either regular or irregular. The method first interpolates in the direction of larger coherence (time or frequency). Using these measurements, the density of pilot symbols in the direction of faster change will be increased thereby improving channel estimation without increasing overhead. As such, the results of the first interpolating step can then be used to assist the interpolation in the dimension of smaller coherence (time or frequency).

    摘要翻译: 一种用于改善OFDM通信系统内的信道估计的方法和装置。 OFDM中的信道估计通常借助于导频符号来执行。 导频符号通常在时间和频率上间隔开。 将导频符号插入的频率和时间的集合称为导频模式。 在一些情况下,导频图案是对角线形格子,规则的或不规则的。 该方法首先在较大相干性(时间或频率)的方向内插。 使用这些测量,导频符号在更快变化方向上的密度将增加,从而改善信道估计而不增加开销。 因此,第一内插步骤的结果然后可以用于辅助尺寸较小的相干性(时间或频率)的内插。