公开(公告)号：US20120140922A1

公开(公告)日：2012-06-07

申请号：US12962449

申请日：2010-12-07

申请人： Ramesh Annavajjala ,  Wei Liu ,  Chunjie Duan ,  Toshiaki Koike-Akino ,  Yige Wang

发明人： Ramesh Annavajjala ,  Wei Liu ,  Chunjie Duan ,  Toshiaki Koike-Akino ,  Yige Wang

IPC分类号： H04W12/04

CPC分类号： H04L9/0875 ,  H04L2209/80 ,  H04W12/02 ,  H04W12/04

摘要： The first and second nodes in a wireless network estimate first and second channel response. The first node quantizes the first channel response to produce a first bit sequence, and a feed-forward message, which is transmit as a feed-forward message to the second node. The second node quantizes the second channel response using the feed-forward message to produce and an estimate of the first bit sequence, a second bit sequence and a feed-back message, which is transmitted to the first node. Then, the first and second nodes delete bits in the respective bit sequences using the feed-back and feed-forward message to generate first and second private keys with low bit mismatch rate.

摘要翻译： 无线网络中的第一和第二节点估计第一和第二信道响应。 第一节点量化第一信道响应以产生第一比特序列，以及作为前馈消息作为第二节点发送的前馈消息。 第二节点使用前馈消息量化第二信道响应，以产生第一比特序列，第二比特序列和反馈消息的估计，其被发送到第一节点。 然后，第一和第二节点使用反馈和前馈消息删除各个比特序列中的比特，以产生具有低比特失配率的第一和第二私钥。

公开(公告)号：US20120002753A1

公开(公告)日：2012-01-05

申请号：US12827591

申请日：2010-06-30

申请人： Ramesh Annavajjala ,  Philip V. Orlik

发明人： Ramesh Annavajjala ,  Philip V. Orlik

IPC分类号： H04L27/00 ,  H04L27/36

CPC分类号： H04L5/0023 ,  H04L1/0606 ,  H04L1/0618 ,  H04L5/0048 ,  H04L25/0226 ,  H04L25/03343 ,  H04L27/345 ,  H04L2025/03426

摘要： A set of data symbols is selected from a set of modulation constellation, and a sample-mean of the set of data symbols is determined. Each data symbol is first shifted by the sample-mean to obtain a shifted data symbol, and then the shifted symbol is multiplied by a first constant to obtain a scaled data symbol. A second constant is added to the scaled data symbol to obtain a mapped data symbol. The sample-mean is multiplied by a third constant to obtain a sample-mean mapped symbol. The set of mapped data symbols and the sample-mean mapped symbol are then transmitted as a resource block.

摘要翻译： 从一组调制星座中选择一组数据符号，并且确定该组数据符号的采样均值。 首先将每个数据符号移位采样均值以获得移位的数据符号，然后将移位符号乘以第一常数以获得缩放的数据符号。 将第二常数添加到缩放的数据符号以获得映射的数据符号。 将样本均值乘以第三常数以获得样本均值映射符号。 然后将映射数据符号集合和采样均值映射符号作为资源块发送。

公开(公告)号：US20230291511A1

公开(公告)日：2023-09-14

申请号：US17691663

申请日：2022-03-10

申请人： Ramesh Annavajjala ,  Kuntal Chowdhury

发明人： Ramesh Annavajjala ,  Kuntal Chowdhury

IPC分类号： H04L5/00 ,  G01S13/04

CPC分类号： H04L5/0023 ,  G01S13/04

摘要： Complex-valued waveform samples in time-domain, frequency-domain and spatial-domain are organized into a plurality of dimensions. A vector of complex-valued samples is extracted from a multidimensional sample buffer. An input transform is applied to a vector of complex-valued samples to produce two vectors of real-valued samples. Each real-valued sample vector is processed to produce a two-dimensional codebook matrix and to generate a vector of indices into the columns of the generated codebook. The two indices vectors are merged to produce an encoded index stream. The encoded index stream along with the two codebooks is used to produce real-valued sample vectors. An output transform is applied to two real-valued sample vectors to produce a vector of complex-valued samples.

公开(公告)号：US08811545B2

公开(公告)日：2014-08-19

申请号：US13291546

申请日：2011-11-08

申请人： Ramesh Annavajjala ,  Liangbin Li ,  Philip Orlik

发明人： Ramesh Annavajjala ,  Liangbin Li ,  Philip Orlik

IPC分类号： H04L27/06 ,  H04L23/02

CPC分类号： H04L5/0048 ,  H04J11/004 ,  H04L25/03171 ,  H04L27/2602 ,  H04L27/32 ,  H04L2025/03777

摘要： Interference in a received orthogonal frequency division multiplexing (OFDM) symbol, modulated according to selected constellation points sk, is reduced. The symbol includes a set of pilot signals and a set of data signals yk, where k is a number of consecutive subcarriers used for the pilot and the data signals. The pilot signals are thresholded to detect interfering pilot signals, which are then erased. Channels Ĥk are estimated using remaining pilot signals. The set of data signals are decoded based on the estimated channels Ĥk, and, for each bit bi in the set of data signals, a logarithmic likely ratio (LLR) log ⁢ ∑ s k : b i = 0 ⁢ 1  y k - H ^ k ⁢ s k  2 ∑ s k : b i = 1 ⁢ 1  y k - H ^ k ⁢ s k  2 is determined. The LLR is an indicator of the likely interference.

摘要翻译： 根据所选择的星座点sk进行调制的接收正交频分复用（OFDM）符号中的干扰被减少。 符号包括一组导频信号和一组数据信号y k，其中k是用于导频和数据信号的连续副载波的数量。 导频信号被阈值以检测干扰导频信号，然后擦除导频信号。 使用剩余的导频信号估计信道Ĥk。 基于估计的信道Ĥk对该组数据信号进行解码，并且对于数据信号组中的每个比特bi，存在对数可能比（LLR）logΣΣsk：bi = 0 1yk-H ^ k skë2Σsk：bi = 1 1yk-H ^ k sk守2。 LLR是可能的干扰的指标。

公开(公告)号：US20130176174A1

公开(公告)日：2013-07-11

申请号：US13346889

申请日：2012-01-10

申请人： Ramesh Annavajjala ,  Philip Orlik

发明人： Ramesh Annavajjala ,  Philip Orlik

IPC分类号： G01S1/24

CPC分类号： G01S5/0221

摘要： A method estimates the time-of-arrival (ToA) of signals received via multipath channels. The received signal of a number of trials is first passed through a band-pass filter and then sampled. The presence of a channel tap within a time window is estimated by comparing a threshold to a largest eigenvalue of the covariance matrix of a time window. The signal samples are used to calculated a band region of a complete covariance matrix. After the band region has been updated for all signal samples, the covariance matrices for a moving window can be extracted from the band region. The ToA is estimated as the ending time of the leading window, which is the earliest window, such that the largest eigenvalue is larger than a given threshold.

摘要翻译： 一种方法估计通过多径信道接收的信号的到达时间（ToA）。 多次试验的接收信号首先通过带通滤波器，然后采样。 通过将阈值与时间窗的协方差矩阵的最大特征值进行比较来估计时间窗内的通道抽头的存在。 信号样本用于计算完整协方差矩阵的带区域。 在针对所有信号样本更新了带区域之后，可以从带区域提取用于移动窗口的协方差矩阵。 ToA被估计为作为最早窗口的前导窗口的结束时间，使得最大特征值大于给定阈值。

公开(公告)号：US08509330B2

公开(公告)日：2013-08-13

申请号：US12894994

申请日：2010-09-30

申请人： Ramesh Annavajjala ,  Hobin Kim

发明人： Ramesh Annavajjala ,  Hobin Kim

IPC分类号： H04K1/10

CPC分类号： H04L5/0048 ,  H04L5/0007 ,  H04L25/0204 ,  H04L25/0212 ,  H04L25/022 ,  H04L25/0228 ,  H04L25/0242

摘要： Time-varying and frequency-selective channels in an orthogonal frequency division multiplexing (OFDM) network are estimated by first storing, in a buffer at a receiver, a received signal corresponding to a set of pilot tones of a set of OFDM symbols. The pilot tones are predetermined and inserted in frequency subcarriers and time slots of the OFDM symbol. A covariance matrix of the received signal is estimated. A diagonal matrix is estimated based on the covariance matrix and a variance of noise in the received signal. The diagonal matrix indicates delays of non-zero paths in a time domain. A channel impulse response (CIR) for each OFDM symbol is estimated using the diagonal matrix, and the received signal. Then, the CIR is transformed to the frequency domain to obtain the channel frequency response (CFR).

摘要翻译： 通过首先在接收机的缓冲器中存储对应于一组OFDM符号的一组导频音调的接收信号来估计正交频分复用（OFDM）网络中的时变和频率选择信道。 导频音被预先确定并插入在OFDM符号的频率子载波和时隙中。 估计接收信号的协方差矩阵。 基于协方差矩阵和接收信号中的噪声方差来估计对角矩阵。 对角矩阵表示时域中非零路径的延迟。 使用对角矩阵和接收信号来估计每个OFDM符号的信道脉冲响应（CIR）。 然后，将CIR转换到频域以获得信道频率响应（CFR）。

公开(公告)号：US20130114765A1

公开(公告)日：2013-05-09

申请号：US13291546

申请日：2011-11-08

申请人： Ramesh Annavajjala ,  Liangbin Li ,  Philip Orlik

发明人： Ramesh Annavajjala ,  Liangbin Li ,  Philip Orlik

IPC分类号： H04L27/06

CPC分类号： H04L5/0048 ,  H04J11/004 ,  H04L25/03171 ,  H04L27/2602 ,  H04L27/32 ,  H04L2025/03777

摘要： Interference in a received orthogonal frequency division multiplexing (OFDM) symbol, modulated according to selected constellation points Sk, is reduced. The symbol includes a set of pilot signals and a set of data signals yk, where k is a number of consecutive subcarriers used for the pilot and the data signals. The pilot signals are thresholded to detect interfering pilot signals, which are then erased. Channels Ĥk are estimated using remaining pilot signals. The set of data signals are decoded based on the estimated channels Ĥk, and, for each bit bi in the set of data signals, a logarithmic likely ratio (LLR) log  ∑ s k : b i = 0  1  y k - H ^ k  s k  2 ∑ s k : b i = 1  1  y k - H ^ k  s k  2 is determined. The LLR is an indicator of the likely interference.

摘要翻译： 根据选择的星座点Sk进行调制的接收正交频分复用（OFDM）符号中的干扰被减少。 符号包括一组导频信号和一组数据信号yk，其中k是用于导频和数据信号的连续副载波的数量。 导频信号被阈值以检测干扰导频信号，然后擦除导频信号。 使用剩余的导频信号估计信道Hk。 基于估计的信道H k解码数据信号组，并且对于数据信号组中的每个比特bi，存在对数可能比率（LLR）logΣΣΣKi：k = 2Σsk：2 LLR是可能的干扰的指标。

公开(公告)号：US08023915B2

公开(公告)日：2011-09-20

申请号：US12413868

申请日：2009-03-30

申请人： Philip V. Orlik ,  Raymond Yim ,  Ramesh Annavajjala ,  Jinyun Zhang

发明人： Philip V. Orlik ,  Raymond Yim ,  Ramesh Annavajjala ,  Jinyun Zhang

IPC分类号： H04B1/06 ,  H04B7/00

CPC分类号： H04B7/0617 ,  H04B7/086

摘要： Beams are used to communicate in a wireless network including mobile and stationary receivers. The network operates according to the IEEE 802.11p in wireless access to vehicular environments (WAVE). A direction from the mobile transceiver to the stationary receiver is predicted using geographic information available to the mobile transceiver. A set of signals are received in the mobile transceiver from the stationary transceiver, wherein the signals are received by an array of antennas, and wherein the signals are received using a set of beams, and wherein each beam is approximately directed at the stationary receiver. A signal-to-noise ratio (SNR) is measured for each beam, and the beam with an optimal SNR is selected as an optimal beam for communicating data between the mobile transceiver and the stationary transceiver.

摘要翻译： 光束用于在包括移动和固定接收机的无线网络中进行通信。 该网络根据IEEE 802.11p在无线接入车辆环境（WAVE）中运行。 使用可用于移动收发机的地理信息来预测从移动收发机到固定接收机的方向。 在固定收发器中的移动收发器中接收一组信号，其中信号由天线阵列接收，并且其中使用一组波束接收信号，并且其中每个波束近似地指向固定接收机。 测量每个波束的信噪比（SNR），并且选择具有最佳SNR的波束作为用于在移动收发器和固定收发器之间传送数据的最佳波束。

公开(公告)号：US20100272014A1

公开(公告)日：2010-10-28

申请号：US12732275

申请日：2010-03-26

申请人： Philip V. Orlik ,  Ron Porat ,  Ramesh Annavajjala ,  Man-On Pun

发明人： Philip V. Orlik ,  Ron Porat ,  Ramesh Annavajjala ,  Man-On Pun

IPC分类号： H04W40/00

CPC分类号： H04B7/0417 ,  H04B7/0469 ,  H04B7/0626 ,  H04B7/0636 ,  H04B7/0663

摘要： Channel state information in a closed-loop, multiple-input, multiple-output wireless networks is fed back from each mobile station to a base station by first determining a transmit covariance matrix R, and applying a singular value decomposition (SVD) R=UΣVH, where U, V are left and right singular vector matrices, Σ is a diagonal matrix with singular values. The matrix V includes column vectors V. A beamforming vector vmax=[1 exp(jΦ)exp(j2Φ) . . . exp(jΦ)]/√{square root over (N)}] is approximated by the column vector V having a maximum magnitude, where Φ is a real number. Then, only the angle Φ is fed back using a phase modulation mapping of the components exp(jΦ) onto the associated subcarrier.

摘要翻译： 闭环多输入多输出无线网络中的信道状态信息通过首先确定发射协方差矩阵R，从每个移动台反馈到基站，并应用奇异值分解（SVD）R = U＆Sgr ; VH，其中U，V是左和右奇异矢量矩阵，＆Sgr; 是具有奇异值的对角矩阵。 矩阵V包括列向量V.波束形成向量vmax = [1exp（jΦ）exp（j2Φ））。 。 。 exp（jΦ）] /√{平方根（N）}]由具有最大幅度的列向量V近似，其中Φ是实数。 然后，仅使用分量exp（jΦ）的相位调制映射到相关联的子载波上来反馈角度Φ。

公开(公告)号：US20230262485A1

公开(公告)日：2023-08-17

申请号：US17671456

申请日：2022-02-14

申请人： Ramesh Annavajjala ,  Kuntal Chowdhury

发明人： Ramesh Annavajjala ,  Kuntal Chowdhury

IPC分类号： H04W24/02 ,  H04B7/06 ,  H04W28/06 ,  G01S7/02

CPC分类号： H04W24/02 ,  H04B7/0617 ,  H04W28/06 ,  G01S7/02

摘要： A plurality of radar sensors and radio units are controlled and processed by a signal processing unit (SPU). Each radar sensor receives configuration, control, power management, and calibration messages along with compressed data stream for transmission from the SPU over a multi Giga-bit interface (MGBI). Each radar sensor transmits status messages and compressed received data stream to the SPU over an MGBI. The SPU performs radar signal processing and tracking upon decompressing the data stream received from the radar sensor. Each radio unit receives configuration, control, power management, and calibration messages along with compressed frequency-domain waveform samples for each transmitter antenna port and for each component carrier configured by the SPU over an MGBI. Each radio unit transmits status messages along with compressed calibration data and compressed frequency-domain waveform samples for each receive antenna port and for each component carrier configured by the SPU over an MGBI. The SPU decompresses the frequency-domain waveform samples, and performs radio baseband signal processing including channel estimation, transmit beamforming, and receive beamforming. The SPU establishes and maintains time synchronization with each radar sensor and radio unit connected to it over an MGBI.