公开(公告)号：US08619717B2

公开(公告)日：2013-12-31

申请号：US12690307

申请日：2010-01-20

申请人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

发明人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

IPC分类号： H04B7/00

CPC分类号： H04L1/0618 ,  H04B7/0417 ,  H04B7/0443 ,  H04B7/0465 ,  H04B7/0615 ,  H04B7/0891 ,  H04W52/34 ,  H04W52/42

摘要： A rate adaptive transmission scheme for MIMO systems, which can transmit a variable number of data symbol streams, provide transmit diversity for each data symbol stream, and fully utilize the total transmit power of the system and the full power of each antenna. In one method, at least one data symbol stream is received for transmission from a plurality of antennas. Each data symbol stream is scaled with a respective weight corresponding to the amount of transmit power allocated to that stream. The scaled data symbol stream(s) are multiplied with a transmit basis matrix to provide a plurality of transmit symbol streams for the plurality of antennas. The transmit basis matrix (e.g., a Walsh-Hadamard matrix or a DFT matrix) is defined such that each data symbol stream is transmitted from all antennas and each transmit symbol stream is transmitted at (or near) the full power for the associated antenna.

摘要翻译： 可以传输可变数量的数据符号流的MIMO系统的速率自适应传输方案为每个数据符号流提供发射分集，并且充分利用系统的总发射功率和每个天线的全功率。 在一种方法中，接收至少一个数据符号流用于从多个天线发射。 每个数据符号流用对应于分配给该流的发射功率的量的相应权重进行缩放。 缩放的数据符号流与发射基矩阵相乘以为多个天线提供多个发射符号流。 定义发射基矩阵（例如，沃尔什 - 哈达玛矩阵或DFT矩阵），使得每个数据符号流从所有天线发送，并且每个发射符号流以（或接近）相关天线的全功率发射。

公开(公告)号：US08599764B2

公开(公告)日：2013-12-03

申请号：US10968702

申请日：2004-10-18

申请人： Rajiv Vijayan ,  Kent Gordon Walker ,  Richard Doil Lane ,  Dhinakar Radhakrishnan ,  Ramaswamy Murali

发明人： Rajiv Vijayan ,  Kent Gordon Walker ,  Richard Doil Lane ,  Dhinakar Radhakrishnan ,  Ramaswamy Murali

IPC分类号： H04W4/00

CPC分类号： H04W4/06 ,  H04W52/0216 ,  H04W72/005 ,  Y02D70/10

摘要： Techniques for transmitting overhead information to facilitate efficient reception of individual data streams are described. A base station may transmit multiple data streams on multiple data channels (or MLCs). The MLCs may be transmitted at different times and on different frequency subbands. The time-frequency location of each MLC may change over time. The overhead information indicates the time-frequency location of each MLC and may be sent as “composite” and “embedded” overhead information. The composite overhead information indicates the time-frequency locations of all MLCs and is sent periodically in each super-frame. A wireless device receives the composite overhead information, determines the time-frequency location of each MLC of interest, and receives each MLC at the indicated time-frequency location. The embedded overhead information for each MLC indicates the time-frequency location of that MLC in the next super-frame and is transmitted along with the payload of the MLC in the current super-frame.

摘要翻译： 描述了用于发送开销信息以促进单个数据流的有效接收的技术。 基站可以在多个数据信道（或MLC）上发送多个数据流。 MLC可以在不同的时间和在不同的频率子带上传输。 每个MLC的时间 - 频率位置可能随时间而变化。 开销信息指示每个MLC的时间 - 频率位置，并且可以作为“复合”和“嵌入”开销信息发送。 复合开销信息表示所有MLC的时间 - 频率位置，并且在每个超帧中周期性地发送。 无线设备接收复合开销信息，确定感兴趣的每个MLC的时间 - 频率位置，并且在指定的时间 - 频率位置接收每个MLC。 每个MLC的嵌入式开销信息指示该MLC在下一个超帧中的时间 - 频率位置，并与当前超帧中的MLC的有效载荷一起发送。

公开(公告)号：US20110058469A1

公开(公告)日：2011-03-10

申请号：US12948759

申请日：2010-11-18

申请人： Michael Mao Wang ,  Bojan Vrcelj ,  Krishna Kiran Mukkavilli ,  Raghuraman Krishnamoorthi ,  Rajiv Vijayan

发明人： Michael Mao Wang ,  Bojan Vrcelj ,  Krishna Kiran Mukkavilli ,  Raghuraman Krishnamoorthi ,  Rajiv Vijayan

IPC分类号： H04J11/00 ,  H04L27/28

CPC分类号： H04L5/0048 ,  H04L5/0007 ,  H04L5/0083 ,  H04L27/261

摘要： The embodiments utilize OFDM symbols to communicate network IDs. The IDs are encoded into symbols utilizing the network IDs as seeds to scramble respective pilots that are then transmitted by utilizing the symbols. The pilots can be structured into a single OFDM symbol and/or multiple OFDM symbols. The single symbol structure for transmitting the network IDs is independent of the number of network ID bits and minimizes frequency offset and Doppler effects. The multiple symbol structure allows a much coarser timing accuracy to be employed at the expense of transmitting additional symbols. Several embodiments employ a search function to find possible network ID candidates from a transmitted symbol and a selection function to find an optimum candidate from a network ID candidate list.

摘要翻译： 这些实施例利用OFDM符号来传送网络ID。 ID被编码成使用网络ID作为种子的符号，以对通过利用符号进行发送的各个导频进行加扰。 导频可以被构造成单个OFDM符号和/或多个OFDM符号。 用于发送网络ID的单个符号结构与网络ID比特数无关，并且使频偏和多普勒效应最小化。 多符号结构允许以牺牲传输附加符号为代价采用更粗糙的定时精度。 几个实施例采用搜索功能来从发送的符号和选择功能中找到可能的网络ID候选，以从网络ID候选列表中找到最佳候选。

公开(公告)号：US20070153687A1

公开(公告)日：2007-07-05

申请号：US11686772

申请日：2007-03-15

申请人： Rashid Attar ,  Rajiv Vijayan ,  Roberto Padovani ,  Nagabhushana Sindhushayana ,  Qiang Wu ,  Peter Black ,  Eduardo Esteves

发明人： Rashid Attar ,  Rajiv Vijayan ,  Roberto Padovani ,  Nagabhushana Sindhushayana ,  Qiang Wu ,  Peter Black ,  Eduardo Esteves

IPC分类号： H04L12/26 ,  H04Q7/00

CPC分类号： H04W48/20 ,  H04L1/20 ,  H04W52/24 ,  H04W52/26

摘要： Methods and apparatus for selecting a serving sector in a high rate data (HDR) communication system are disclosed. An exemplary HDR communication system defines a set of data rates, at which a sector of an Access Point may send data packets to an Access Terminal. The sector is selected by the Access Terminal to achieve the highest data throughput while maintaining a targeted packet error rate. The Access Terminal employs various methods to evaluate quality metrics of forward and reverse links from and to different sectors, and uses the quality metrics to select the sector to send data packets to the Access Terminal.

摘要翻译： 公开了在高速率数据（HDR）通信系统中选择服务扇区的方法和装置。 示例性HDR通信系统定义了一组数据速率，在该组数据速率下，接入点的扇区可以向接入终端发送数据分组。 访问终端选择该扇区以实现最高的数据吞吐量，同时保持目标分组错误率。 接入终端采用各种方法来评估来自不同扇区的前向和反向链路的质量度量，并使用质量度量来选择扇区将数据分组发送到接入终端。

公开(公告)号：US07177648B2

公开(公告)日：2007-02-13

申请号：US10728635

申请日：2003-12-05

申请人： Rashid A. Attar ,  Rajiv Vijayan ,  Roberto Padovani ,  Nagabhushana T. Sindhushayana ,  Qiang Wu ,  Peter J. Black ,  Eduardo A. S. Esteves

发明人： Rashid A. Attar ,  Rajiv Vijayan ,  Roberto Padovani ,  Nagabhushana T. Sindhushayana ,  Qiang Wu ,  Peter J. Black ,  Eduardo A. S. Esteves

IPC分类号： H04Q7/20

CPC分类号： H04W36/18 ,  H04L1/20 ,  H04W36/30 ,  H04W52/24 ,  H04W52/26

摘要： Methods and apparatus for selecting a serving sector in a high rate data (HDR) communication system are disclosed. An exemplary HDR communication system defines a set of data rates, at which a sector of an Access Point may send data packets to an Access Terminal. The sector is selected by the Access Terminal to achieve the highest data throughput while maintaining a targeted packet error rate. The Access Terminal employs various methods to evaluate quality metrics of forward and reverse links from and to different sectors, and uses the quality metrics to select the sector to send data packets to the Access Terminal.

摘要翻译： 公开了在高速率数据（HDR）通信系统中选择服务扇区的方法和装置。 示例性HDR通信系统定义了一组数据速率，在该组数据速率下，接入点的扇区可以向接入终端发送数据分组。 访问终端选择该扇区以实现最高的数据吞吐量，同时保持目标分组错误率。 接入终端采用各种方法来评估来自不同扇区的前向和反向链路的质量度量，并使用质量度量来选择扇区将数据分组发送到接入终端。

公开(公告)号：US07054632B2

公开(公告)日：2006-05-30

申请号：US10007301

申请日：2001-11-08

申请人： Rashid Ahmed Attar ,  Rajiv Vijayan ,  Nagabhushana T. Sindhushayana

发明人： Rashid Ahmed Attar ,  Rajiv Vijayan ,  Nagabhushana T. Sindhushayana

IPC分类号： H04Q7/20

CPC分类号： H04W36/18 ,  H04L1/20 ,  H04W36/30 ,  H04W52/24 ,  H04W52/26

摘要： Methods and apparatus for an adaptive set management in a communication system are disclosed. Certain levels of an imbalance between a forward link and a reverse link are always present in a communication system. Although severe levels of an imbalance cause a detrimental effect on quality of communication and throughput, the imbalance is an issue only if it degrades throughput by one rate on the forward link. Consequently, an adaptive set management evaluates an imbalance among sectors in a subscriber station's list in accordance with the quality metric of the forward link and the reverse link, and removes from the subscriber station's list only a sector that causes severe imbalance. Although retaining a sector in the subscriber station's list may improve throughput, it may negatively affect other functions of the communication system, e.g., power control. Therefore, a method of power control is modified if a level of imbalance affecting the power control is detected.

公开(公告)号：US20050135308A1

公开(公告)日：2005-06-23

申请号：US10968614

申请日：2004-10-18

申请人： Rajiv Vijayan ,  Gordon Walker ,  Raghu Krishnamoorthi ,  Ramaswamy Murali

发明人： Rajiv Vijayan ,  Gordon Walker ,  Raghu Krishnamoorthi ,  Ramaswamy Murali

IPC分类号： H04L27/28

CPC分类号： H04L27/0008 ,  H04L5/0007 ,  H04L5/0041 ,  H04L5/0044 ,  H04L5/0051 ,  H04L5/0064 ,  H04L25/022 ,  H04L25/0226 ,  H04L25/0228 ,  H04L27/2604 ,  H04L27/2605 ,  H04L27/2647 ,  Y02D70/10

摘要： Techniques for multiplexing multiple data streams using frequency division multiplexing (FDM) in an OFDM system are described. M disjoint “interlaces” are formed with U usable subbands. Each interlace is a different set of S subbands, where U=M·S. The subbands for each interlace are interlaced with the subbands for each of the other M−1 interlaces. M slots may be defined for each symbol period and assigned slot indices 1 through M. The slot indices may be mapped to interlaces such that (1) frequency diversity is achieved for each slot index and (2) the interlaces used for pilot transmission have varying distances to the interlaces used for each slot index, which improves channel estimation performance. Each data stream may be processed as data packets of a fixed size, and different numbers of slots may be used for each data packet depending on the coding and modulation scheme used for the data packet.

摘要翻译： 描述了在OFDM系统中使用频分复用（FDM）来复用多个数据流的技术。 M个不相交的“交错”与U个可用的子带形成。 每个交错是S个子带的不同集合，其中U = M.S。 用于每个交错的子带与用于其它M-1交错的每个子带进行隔行扫描。 可以为每个符号周期和分配的时隙索引1到M定义M个时隙。时隙索引可以被映射到交织，使得（1）针对每个时隙索引实现频率分集，以及（2）用于导频传输的交织具有不同的 到每个时隙索引用于交织的距离，这提高了信道估计性能。 每个数据流可以被处理为固定大小的数据分组，并且根据用于数据分组的编码和调制方案，每个数据分组可以使用不同数量的时隙。

公开(公告)号：US06873606B2

公开(公告)日：2005-03-29

申请号：US10367234

申请日：2003-02-14

申请人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

发明人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

IPC分类号： H04B7/00 ,  H04B7/005 ,  H04B7/04 ,  H04B7/06 ,  H04B7/08 ,  H04J99/00 ,  H04L1/00 ,  H04L1/06 ,  H04B1/02

CPC分类号： H04L1/0618 ,  H04B7/0417 ,  H04B7/0443 ,  H04B7/0465 ,  H04B7/0615 ,  H04B7/0891 ,  H04W52/34 ,  H04W52/42

摘要： A rate adaptive transmission scheme for MIMO systems, which can transmit a variable number of data symbol streams, provide transmit diversity for each data symbol stream, and fully utilize the total transmit power of the system and the full power of each antenna. In one method, at least one data symbol stream is received for transmission from a plurality of antennas. Each data symbol stream is scaled with a respective weight corresponding to the amount of transmit power allocated to that stream. The scaled data symbol stream(s) are multiplied with a transmit basis matrix to provide a plurality of transmit symbol streams for the plurality of antennas. The transmit basis matrix (e.g., a Walsh-Hadamard matrix or a DFT matrix) is defined such that each data symbol stream is transmitted from all antennas and each transmit symbol stream is transmitted at (or near) the full power for the associated antenna.

摘要翻译： 可以传输可变数量的数据符号流的MIMO系统的速率自适应传输方案为每个数据符号流提供发射分集，并且充分利用系统的总发射功率和每个天线的全功率。 在一种方法中，接收至少一个数据符号流用于从多个天线发射。 每个数据符号流用对应于分配给该流的发射功率的量的相应权重进行缩放。 缩放的数据符号流与发射基矩阵相乘以为多个天线提供多个发射符号流。 定义发射基矩阵（例如，沃尔什 - 哈达玛矩阵或DFT矩阵），使得每个数据符号流从所有天线发送，并且每个发射符号流以（或接近）相关天线的全功率发射。

公开(公告)号：US20050013239A1

公开(公告)日：2005-01-20

申请号：US10919698

申请日：2004-08-16

申请人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

发明人： Avneesh Agrawal ,  Rajiv Vijayan ,  Tamer Kadous

IPC分类号： H04B7/00 ,  H04B7/005 ,  H04B7/04 ,  H04B7/06 ,  H04B7/08 ,  H04J99/00 ,  H04L1/00 ,  H04L1/06 ,  H04J11/00 ,  H04Q7/00

CPC分类号： H04L1/0618 ,  H04B7/0417 ,  H04B7/0443 ,  H04B7/0465 ,  H04B7/0615 ,  H04B7/0891 ,  H04W52/34 ,  H04W52/42

摘要： A rate adaptive transmission scheme for MIMO systems, which can transmit a variable number of data symbol streams, provide transmit diversity for each data symbol stream, and fully utilize the total transmit power of the system and the full power of each antenna. In one method, at least one data symbol stream is received for transmission from a plurality of antennas. Each data symbol stream is scaled with a respective weight corresponding to the amount of transmit power allocated to that stream. The scaled data symbol stream(s) are multiplied with a transmit basis matrix to provide a plurality of transmit symbol streams for the plurality of antennas. The transmit basis matrix (e.g., a Walsh-Hadamard matrix or a DFT matrix) is defined such that each data symbol stream is transmitted from all antennas and each transmit symbol stream is transmitted at (or near) the full power for the associated antenna.

摘要翻译： 可以传输可变数量的数据符号流的MIMO系统的速率自适应传输方案为每个数据符号流提供发射分集，并且充分利用系统的总发射功率和每个天线的全功率。 在一种方法中，接收至少一个数据符号流用于从多个天线发射。 每个数据符号流用对应于分配给该流的发射功率的量的相应权重进行缩放。 缩放的数据符号流与发射基矩阵相乘以为多个天线提供多个发射符号流。 定义发射基矩阵（例如，沃尔什 - 哈达玛矩阵或DFT矩阵），使得每个数据符号流从所有天线发送，并且每个发射符号流以（或接近）相关天线的全功率发射。

公开(公告)号：US06330291B1

公开(公告)日：2001-12-11

申请号：US08625481

申请日：1996-03-29

申请人： Avneesh Agrawal ,  Rajiv Vijayan

发明人： Avneesh Agrawal ,  Rajiv Vijayan

IPC分类号： H04L27233

CPC分类号： H04B1/7085 ,  H04B1/709

摘要： A frequency tracking loop for a communication system using orthogonal Walsh modulation is provided. The frequency tracking loop includes a correlator (120), such as a fast Hadamard transformation device, and a discriminator (130). The correlator (120) produces a correlation vector (122) representing the result of correlating the input signal with each of a set of Walsh functions, with corresponding index values. The discriminator (130) produces a frequency error signal (ê) based on the correlator (120) output with the highest energy level and other correlator outputs whose indices are related to the index of highest energy correlator output by powers of two. The frequency error signal (ê) is generated by producing a cross product between the highest energy output and one or more of the other related correlator outputs. In further aspects, a filter (140) can be used to further shape the resulting error signal (ê) and form a frequency offset estimate signal ({circumflex over (f)}).

摘要翻译： 提供了一种使用正交沃尔什调制的通信系统的频率跟踪环路。 频率跟踪环路包括诸如快速哈达玛变换装置的相关器（120）和鉴别器（130）。 相关器（120）产生表示将输入信号与一组沃尔什函数中的每一个相关联的结果与相应索引值相关的向量（122）。 鉴别器（130）基于以最高能级输出的相关器（120）和其他相关器输出产生频率误差信号（ê），其相关指数与两个功率的最高能量相关器输出的指标相关。 频率误差信号（ê）通过产生最高能量输出和一个或多个其它相关相关器输出之间的交叉积来产生。 在另外的方面，可以使用滤波器（140）来进一步调整所得到的误差信号（ê）并形成频率偏移估计信号（{（f（f）}）。