公开(公告)号：US08718174B2

公开(公告)日：2014-05-06

申请号：US13562738

申请日：2012-07-31

Applicant: Narayan Prasad ,  Guosen Yue ,  Mohammad A. Khojastepour ,  Meilong Jiang ,  Sam Path Rangarajan

Inventor： Narayan Prasad ,  Guosen Yue ,  Mohammad A. Khojastepour ,  Meilong Jiang ,  Sam Path Rangarajan

IPC: H04B7/02

CPC classification number: H04B7/0452 ,  H04J11/0046 ,  H04L5/0023 ,  H04L25/03331 ,  H04L27/0008 ,  H04L27/0012 ,  H04L27/34 ,  H04W72/042 ,  H04W72/12

Abstract: A method implemented in a user equipment used in a multi-user multiple input multiple output (MU-MIMO) wireless communications system is disclosed. The method includes receiving from a base station an indication of a first modulation type for the user equipment, receiving a first data signal for the user equipment, receiving a second data signal for a co-scheduled user equipment, where a second modulation type for the co-scheduled user equipment is unknown to the user equipment, and deciding the second modulation type. Other methods, systems, and apparatuses also are disclosed.

Abstract translation: 公开了一种在多用户多输入多输出（MU-MIMO）无线通信系统中使用的用户设备中实现的方法。 该方法包括从基站接收用户设备的第一调制类型的指示，接收用户设备的第一数据信号，为共同调度的用户设备接收第二数据信号，其中第二调制类型为 共同调度的用户设备对于用户设备是未知的，并且确定第二调制类型。 还公开了其它方法，系统和装置。

公开(公告)号：US08699621B2

公开(公告)日：2014-04-15

申请号：US13252650

申请日：2011-10-04

Applicant: Guosen Yue ,  Narayan Prasad ,  Meilong Jiang ,  Sampath Rangarajan

Inventor： Guosen Yue ,  Narayan Prasad ,  Meilong Jiang ,  Sampath Rangarajan

IPC: H04L27/00

CPC classification number: H04B7/0456 ,  H04L1/0618 ,  H04L1/1896 ,  H04L25/03343 ,  H04L2025/03426

Abstract: A method includes obtaining a precoder for retransmission of one codeword responsive to a known precoding matrix of a certain rank and modulation and coding scheme assignments used in an original transmission, and a desired retransmission rank', forming an approximate channel covariance matrix; stimating an a minimum mean square error receiver signal-to-noise-interference-ratio for each layer to be retransmitted responsive to the prior forming; and finding a precoding matrix from a preceding codebook that maximizes a sum-rate for enabling precoding selections for retransmissions in uplink multiple-input multiple-output MIMO hybrid automatic repeat request HARQ.

Abstract translation: 一种方法包括响应于某一秩的已知预编码矩阵和在原始传输中使用的调制和编码方案分配以及形成近似信道协方差矩阵的期望重传等级来获得用于重传一个码字的预编码器; 响应于先前的形成，针对要重传的每个层激发最小均方误差接收机的信噪比干扰比; 以及从上一个码本中找到一个预编码矩阵，该预编码矩阵使上行链路多输入多输出MIMO混合自动重复请求HARQ中的重传的预编码选择最大化。

公开(公告)号：US08687527B2

公开(公告)日：2014-04-01

申请号：US13234885

申请日：2011-09-16

Applicant: Meilong Jiang ,  Narayan Prasad ,  Guosen Yue ,  Sampath Rangarajan

Inventor： Meilong Jiang ,  Narayan Prasad ,  Guosen Yue ,  Sampath Rangarajan

IPC: H04B7/005 ,  H04B1/00

CPC classification number: H04B7/0417 ,  H04B7/0404 ,  H04B7/0486 ,  H04B7/0626 ,  H04B7/063 ,  H04B7/0639 ,  H04J11/0033 ,  H04L1/0031 ,  H04L5/0023

Abstract: An inventive method for link adaptation for an LTE/LTE-A uplink with a turbo SIC receiver includes the steps of determining a precoding matrix index PMI and rank index RI selection for an LTE/LTE-A uplink when precoding of the uplink is enabled, responsive to channel state information of a subcarrier in the uplink; determining a decoding order for codewords in the uplink i) when the precoding of the uplink is not enabled and ii) if needed when the precoding of the uplink is enabled; performing modulation and coding scheme MCS assignment for the uplink based on a hard decision successive interference cancellation SIC rule (without intra-CW cancellation) or a partial hard decision successive interference cancellation SIC rule (with intra-CW cancellation), responsive to the determined PMI and RI selection; and influencing data transmission in the uplink responsive to the MCS assignment for detection by a turbo SIC receiver.

Abstract translation: 用于具有turbo SIC接收机的LTE / LTE-A上行链路的链路适配的创新方法包括以下步骤：当启用上行链路的预编码时，确定LTE / LTE-A上行链路的预编码矩阵索引PMI和秩索引RI选择， 响应于所述上行链路中的子载波的信道状态信息; 确定所述上行链路中的码字的解码顺序i）当所述上行链路的预编码不被使能时，以及ii）如果在启用所述上行链路的预编码时需要; 基于硬判决连续干扰消除SIC规则（无内部CW消除）或部分硬判决连续干扰消除SIC规则（具有CW内取消），执行针对上行链路的调制和编码方案MCS分配，响应于所确定的PMI 和RI选择; 并且响应于用于由turbo SIC接收机检测的MCS分配，影响上行链路中的数据传输。

公开(公告)号：US08644180B2

公开(公告)日：2014-02-04

申请号：US13080403

申请日：2011-04-05

Applicant: Narayan Prasad ,  Guosen Yue ,  Mohammad A. Khojastepour ,  Meilong Jiang ,  Sampath Rangarajan

Inventor： Narayan Prasad ,  Guosen Yue ,  Mohammad A. Khojastepour ,  Meilong Jiang ,  Sampath Rangarajan

IPC: H04L12/26 ,  H04W4/00 ,  H04B7/02

CPC classification number: H04W24/08 ,  H04B7/0452 ,  H04B7/0465 ,  H04B7/0486 ,  H04W52/346 ,  H04W72/0406 ,  H04W72/085

Abstract: Methods and systems for determining attributes of communication channels of MU-MIMO users in an OFDMA system are disclosed. One method includes receiving from a base station, for at least one sub-band of contiguous sub-carriers, an indication of an estimate of or an upper-bound on a total number of streams that are co-scheduled by the base station on the at least one sub-band and an indication of a fraction of a transmit power at the base station that is applied to streams that are scheduled for transmission to a particular user. The method further includes determining one or more signal quality measures for the at least one sub-band based on at least one of the fraction or the estimate of or the upper-bound on the total number of streams that are scheduled by the base station on the at least one sub-band. In addition, an indication of the one or more signal quality measures is transmitted to the base station in the method.

Abstract translation: 公开了一种用于确定OFDMA系统中MU-MIMO用户的通信信道属性的方法和系统。 一种方法包括从基站接收对于连续子载波的至少一个子带，对由基站在...上共同调度的流的总数的估计或上限的指示 至少一个子带和基站处的发送功率的一小部分的指示，其被应用于被调度用于传输到特定用户的流。 该方法还包括基于由基站对其进行调度的流的总数的分数或估计或上限中的至少一个来确定至少一个子带的一个或多个信号质量度量 该至少一个子带。 此外，在该方法中向基站发送一个或多个信号质量测量的指示。

公开(公告)号：US08599951B2

公开(公告)日：2013-12-03

申请号：US13115162

申请日：2011-05-25

Applicant: Mohammad A. Khojastepour ,  Narayan Prasad ,  Sampath Rangarajan

Inventor： Mohammad A. Khojastepour ,  Narayan Prasad ,  Sampath Rangarajan

IPC: H04B7/02 ,  H04L1/02

Abstract: Systems and methods for conveying wireless transmission allocation information are disclosed. In accordance with one method, an index indicating selected data stream parameters is received. In addition, an indication of a number of transmit antennas at a transmitter from which the data stream is transmitted is also received. Further, the selected parameters are determined from the index based on the number of transmit antennas at the transmitter. Moreover, data signals are received and processed with a processor in accordance with the selected data stream parameters.

公开(公告)号：US08494459B2

公开(公告)日：2013-07-23

申请号：US13213510

申请日：2011-08-19

Applicant: Narayan Prasad ,  Mohammad Amir Khojastepour ,  Sampath Rangarajan

Inventor： Narayan Prasad ,  Mohammad Amir Khojastepour ,  Sampath Rangarajan

IPC: H04B7/02 ,  H04L27/28

CPC classification number: H04B7/0417 ,  H04B7/0469 ,  H04B7/0486 ,  H04B7/0632 ,  H04B7/0639 ,  H04B7/0669

Abstract: A precoding scheme in which the downlink channel is estimated and an optimal precoding matrix to be used by the multi antenna transmitter is determined accordingly. The optimal precoding matrix is selected from a codebook of matrices that includes matrices having a structure matched to that of the eigenvectors of the spatial covariance matrix, wherein the spatial covariance matrix is modeled as a Hermitian and Toeplitz matrix parameterized by a single complex-valued scalar.

Abstract translation: 相应地确定其中估计下行链路信道并由多天线发射机使用的最佳预编码矩阵的预编码方案。 从包括具有与空间协方差矩阵的特征向量的结构匹配的矩阵的矩阵的码本中选择最佳预编码矩阵，其中空间协方差矩阵被建模为由单个复值标量参数化的Hermitian和Toeplitz矩阵 。

公开(公告)号：US08472813B2

公开(公告)日：2013-06-25

申请号：US12818154

申请日：2010-06-18

Applicant: Neda Cvijetic ,  Narayan Prasad ,  Dayou Qian ,  Ting Wang

Inventor： Neda Cvijetic ,  Narayan Prasad ,  Dayou Qian ,  Ting Wang

IPC: H04B10/00 ,  H04B10/12

CPC classification number: H04L27/2646 ,  H04B10/548 ,  H04B10/614 ,  H04L25/03891 ,  H04L27/2626 ,  H04L27/2697

Abstract: A polarization-multiplexed (POLMUX) optical orthogonal frequency division multiplexing (OFDM) system with direct detection includes an adaptive dual POLMUX carrier OFDM transmitter; and a block symmetric (B-S) MIMO equalizer coupled to the adaptive dual POLMUX carrier OFDM transmitter through a standard single-mode-fiber (SSMF) feedback path.

Abstract translation: 具有直接检测的偏振复用（POLMUX）光正交频分复用（OFDM）系统包括自适应双波分多址载波OFDM发射机; 以及通过标准单模光纤（SSMF）反馈路径耦合到自适应双POLMUX载波OFDM发射机的块对称（B-S）MIMO均衡器。

公开(公告)号：US20130072210A1

公开(公告)日：2013-03-21

申请号：US13617766

申请日：2012-09-14

Applicant: Honghai Zhang ,  Narayan Prasad ,  Sampath Rangarajan

Inventor： Honghai Zhang ,  Narayan Prasad ,  Sampath Rangarajan

IPC: H04W52/08

CPC classification number: H04W52/146 ,  H04W52/08 ,  H04W52/10 ,  H04W52/242 ,  H04W52/243

Abstract: A method for LTE and LTE-A uplink power control includes open loop power control where user equipment UE measures downlink pathloss which is sent to an eNodeB that determines uplink UL transmit power based on the downlink pathloss.

Abstract translation: 用于LTE和LTE-A上行链路功率控制的方法包括开环功率控制，其中用户设备UE基于下行链路路径损耗测量发送到确定上行链路UL发射功率的eNodeB的下行链路路径损耗。

公开(公告)号：US20120257685A1

公开(公告)日：2012-10-11

申请号：US13524269

申请日：2012-06-15

Applicant: Mohammad A. Khojastepour ,  Narayan Prasad

Inventor： Mohammad A. Khojastepour ,  Narayan Prasad

IPC: H04L25/49 ,  H04B1/10 ,  H04B15/00 ,  H04B7/02

CPC classification number: H04B7/0617 ,  H04B7/0456 ,  H04B7/0632 ,  H04B7/0639

Abstract: A multi-rank beamforming (MRBF) scheme in which the downlink channel is estimated and an optimal precoding matrix to be used by the MRBF transmitter is determined accordingly. The optimal precoding matrix is selected from a codebook of matrices having a recursive structure which allows for efficient computation of the optimal precoding matrix and corresponding Signal to Interference and Noise Ratio (SINR). The codebook also enjoys a small storage footprint. Due to the computational efficiency and modest memory requirements, the optimal precoding determination can be made at user equipment (UE) and communicated to a transmitting base station over a limited uplink channel for implementation over the downlink channel.

公开(公告)号：US20120250804A1

公开(公告)日：2012-10-04

申请号：US13433873

申请日：2012-03-29

Applicant: Narayan Prasad ,  Neda Cvijetic ,  Sampath Rangarajan ,  Ting Wang

Inventor： Narayan Prasad ,  Neda Cvijetic ,  Sampath Rangarajan ,  Ting Wang

IPC: H04L27/06

CPC classification number: H04L25/0246 ,  H04L25/03171 ,  H04L25/067

Abstract: The present invention employs a look up table based implementation for the metric computations which eliminate redundancy and substantially reduce the number of multiplications. Moreover, inventive method exploits the fact that the un-normalized constellation symbols are complex integers so that the product of a real-number and an un-normalized constellation symbol can be implemented by only additions. The inventive method also enables a greater efficiency for whitening colored noise prior to demodulation, one of which involves no square-root operation. The invention results in less complexity, faster operation, lower power consumption, without sacrificing performance

Abstract translation: 本发明使用用于度量计算的查找表实现，其消除冗余并且显着减少乘法次数。 此外，本发明的方法利用了未归一化的星座符号是复数整数的事实，使得实数和未归一化的星座符号的乘积可以仅通过添加来实现。 本发明的方法还使得能够在解调之前增加有色噪声的效率，其中之一不涉及平方根操作。 本发明导致更少的复杂性，更快的操作，更低的功耗，而不会牺牲性能