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31. 发明申请

US20100002785A1 ADAPTIVE THRESHOLDING FOR OFDM CHANNEL ESTIMATION 有权
标题翻译： OFDM信道估计的自适应阈值
公开(公告)号：US20100002785A1
公开(公告)日：2010-01-07
申请号：US12250135
申请日：2008-10-13
申请人： Ashok Mantravadi , Krishna Kiran Mukkavilli , Raghuraman Krishnamoorthi , Rajeev Krishnamurthi
发明人： Ashok Mantravadi , Krishna Kiran Mukkavilli , Raghuraman Krishnamoorthi , Rajeev Krishnamurthi
IPC分类号： H04L27/28
CPC分类号： H04L25/0218 , H04L5/0007 , H04L25/0204 , H04L25/022 , H04L25/0224
摘要： An adaptive thresholding technique eliminates suboptimum threshold values by adjusting for varying channel conditions to eliminate interference where no channel energy is present, without discarding viable taps having useful channel energy. The adaptive thresholding technique adaptively optimizes receive threshold values for both wide and local area channels based only on measured C/I ratios 300. Thresholds are calculated based on instantaneous C/I estimates and/or weighted average C/I estimates calculated from WID/LID energies obtained from the current superframe WIC/LIC symbols respectively. In alternate embodiments, thresholds are calculated based on instantaneous C/I estimates and/or weighted average C/I estimates calculated from WTPC and LTPC symbols for the wide and local area channels, respectively The present adaptive thresholding technique dynamically reduces the threshold as the C/I estimate increases to mitigate performance degradation due to removal of weak signal taps. There is a separate threshold for each of the 12 coding and modulation modes supported by an exemplary receiver.
摘要翻译：自适应阈值技术通过调整不同的信道条件来消除次优阈值，以消除不存在信道能量的干扰，而不丢弃具有有用信道能量的可行分接头。自适应阈值技术仅基于测量的C / I比300自适应地优化宽和局域信道的接收阈值。阈值基于从WID / LID计算的瞬时C / I估计和/或加权平均C / I估计来计算从当前超帧WIC / LIC符号获得的能量。在替代实施例中，基于针对宽和局域信道的WTPC和LTPC符号计算的瞬时C / I估计和/或加权平均C / I估计来计算阈值。当前自适应阈值技术动态地将阈值设置为C /我估计增加以减轻由于去除弱信号抽头而导致的性能下降。对于由示例性接收机支持的12个编码和调制模式中的每一个，存在单独的阈值。

32. 发明授权

US07532688B2 Adaptive thresholding algorithm for the noise due to unknown symbols in correlation based channel impulse response (CIR) estimate 有权
标题翻译：在基于相关的信道脉冲响应（CIR）估计中由于未知符号引起的噪声的自适应阈值算法
公开(公告)号：US07532688B2
公开(公告)日：2009-05-12
申请号：US11690560
申请日：2007-03-23
申请人： Mark Fimoff , Sreenivasa M. Nerayanuru , Christopher J. Pladdy
发明人： Mark Fimoff , Sreenivasa M. Nerayanuru , Christopher J. Pladdy
IPC分类号： H04L1/00 , H04L25/08
CPC分类号： H04L25/0218
摘要： An impulse response is estimated for a channel by estimating an intermediate impulse response of the channel. The intermediate impulse response comprises at least one multipath spike and one or more non-deterministic noise components at locations throughout the channel Then, a threshold function is applied to the estimated intermediate impulse response across at least a portion of the channel in order to provide an estimated final impulse response of the channel. The threshold function has the effect of nulling the noise components of the channel having values less than the threshold function at the location within the channel of the respective noise component, and the threshold function is characterized by a level that varies across the portion of the channel from a minimum value to a maximum value in a manner determined by the location of the at least one multipath spike within the channel.
摘要翻译：通过估计信道的中间脉冲响应来估计信道的脉冲响应。中间脉冲响应包括在整个信道的位置处的至少一个多路径尖峰和一个或多个非确定性噪声分量。然后，阈值函数被应用于跨信道的至少一部分的估计的中间脉冲响应，以便提供估计通道的最终脉冲响应。阈值函数具有使在各个噪声分量的信道内的位置处具有小于阈值函数的信道的噪声分量归零的效果，并且阈值函数的特征在于在信道的整个部分上变化的电平以由通道内的至少一个多径峰值的位置确定的方式从最小值到最大值。

33. 发明申请

US20080317153A1 ADAPTIVE TECHNIQUE FOR INTER-CARRIER-INTERFERENCE CANCELING IN OFDM SYSTEMS 有权
标题翻译： OFDM系统中互操作干扰消除的自适应技术
公开(公告)号：US20080317153A1
公开(公告)日：2008-12-25
申请号：US11766814
申请日：2007-06-22
申请人： Mirette Sadek , Nabil Yousef
发明人： Mirette Sadek , Nabil Yousef
IPC分类号： H04J11/00 , H04L23/02
CPC分类号： H04L25/0216 , H04L1/0047 , H04L1/0054 , H04L25/0218 , H04L25/022 , H04L25/0232 , H04L25/0236 , H04L25/0244 , H04L25/03038 , H04L25/03286 , H04L2025/03414 , H04L2025/03496 , H04L2025/03522 , H04L2025/03617
摘要： ICI canceling in an OFDM system includes taking a FFT of a wireless electrical signal to produce an OFDM signal; estimating a DC component of a frequency-selective channel in the OFDM system; obtaining an initial estimate of data symbols associated with data bits of the OFDM signal; correcting the data bits with a Viterbi decoder; encoding the corrected data bits to acquire corrected data symbols; re-estimating the DC component of the frequency-selective channel using the corrected data symbols; filtering the corrected data symbols and sub-carrier of the frequency-selective channel; calculating a first order differential function of the frequency-selective channel based on successive ones of the corrected data symbols; removing an ICI component from the calculated first order differential function; and re-estimating the data symbols as a function of the removed ICI component. The filtering occurs using a low pass filter comprising a bank of eight filters.
摘要翻译： OFDM系统中的ICI取消包括对无线电信号进行FFT以产生OFDM信号; 估计所述OFDM系统中的频率选择信道的直流分量; 获得与所述OFDM信号的数据比特相关联的数据符号的初始估计; 用维特比解码器校正数据位; 编码校正的数据位以获取校正的数据符号; 使用校正的数据符号重新估计频率选择信道的DC分量; 对频率选择信道的校正数据符号和子载波进行滤波; 基于经校正的数据符号中的连续的一个，计算频率选择信道的一阶微分函数; 从计算的一阶微分函数中去除ICI分量; 并重新估计作为所移除的ICI分量的函数的数据符号。使用包括八个滤波器组的低通滤波器进行滤波。

34. 发明申请

US20030236074A1 Scheme for realizing path selection using optimum path selection threshold in radio communication 有权
标题翻译：在无线电通信中使用最优路径选择阈值实现路径选择的方案
公开(公告)号：US20030236074A1
公开(公告)日：2003-12-25
申请号：US10465612
申请日：2003-06-20
申请人： NTT DoCoMo, Inc
发明人： Hiroyuki Ishii , Takayuki Ishiguro , Sung Uk Moon , Mayu Yamada
IPC分类号： H04B007/00 , H04B001/00 , H04Q007/20
CPC分类号： H04B1/7113 , H04B1/70755 , H04B1/7117 , H04L25/0218
摘要： A receiver of a mobile station or a base station in radio communications is formed by a correlation unit for generating a delay profile for specifying paths by taking correlations by using replica signals for a received pilot signal, and a path selection unit for comparing a power level of each path in the delay profile with a threshold determined according to an index value regarding a communication state, selecting paths for which a comparison result satisfies a prescribed condition as valid paths, and outputting a selected delay profile formed by the valid paths as a channel estimation value.
摘要翻译：无线电通信中的移动站或基站的接收机由相关单元形成，该相关单元通过使用用于接收到的导频信号的复制信号来产生用于指定路径的延迟分布，以及用于比较功率电平的路径选择单元根据与通信状态相关的指标值确定的阈值，选择比较结果满足规定条件的路径作为有效路径，并将由有效路径形成的所选择的延迟分布作为信道输出估计值。

35. 发明授权

US5644603A Maximum-likelihood sequence estimator with variable number of states 失效
标题翻译：具有可变数量状态的最大似然序列估计器
公开(公告)号：US5644603A
公开(公告)日：1997-07-01
申请号：US499402
申请日：1995-07-07
申请人： Akihisa Ushirokawa
发明人： Akihisa Ushirokawa
IPC分类号： H03H21/00 , H03M13/23 , H04B3/10 , H04L25/02 , H04L25/03 , G06F11/10
CPC分类号： H04L25/0218 , H04L25/03292 , H04L25/03203
摘要： A maximum-likelihood sequence estimator (MLSE) with a variable number of states. A channel response estimator calculates channel responses from a received signal having a predetermined burst length and a reference signal. A controller checks the latest (L-th) response having a larger power than a predetermined threshold value of the channel responses and determines the L number of effective channel responses having the larger power. A Viterbi equalizer with a variable number of states executes a maximum-likelihood sequence estimation on the basis of the trellis with M.sup.(L-1) states (M is a multi-value number of a modulation signal) using the L number of effective channel responses. The MLSE is operated with the minimum number of states every burst to reduce an average processing amount without degrading characteristics and to achieve a low consumption power of receivers.
摘要翻译：具有可变数量状态的最大似然序列估计器（MLSE）。信道响应估计器从具有预定突发长度和参考信号的接收信号计算信道响应。控制器检查具有比通道响应的预定阈值大的功率的最新（L）响应，并且确定具有较大功率的L个有效信道响应。具有可变数量状态的维特比均衡器使用L个有效信道执行基于具有M（L-1）状态的网格（M是调制信号的多值数）的最大似然序列估计回应。 MLSE以每个突发的最小状态数来运行，以减少平均处理量而不降低特性并实现接收机的低功耗。

36. 发明授权

US5251233A Apparatus and method for equalizing a corrupted signal in a receiver 失效
标题翻译：用于均衡接收机中损坏的信号的装置和方法
公开(公告)号：US5251233A
公开(公告)日：1993-10-05
申请号：US630922
申请日：1990-12-20
申请人： Gerald P. Labedz , Michael D. Kotzin , Joseph J. Schuler
发明人： Gerald P. Labedz , Michael D. Kotzin , Joseph J. Schuler
IPC分类号： H04B1/10 , H04B7/005 , H04L25/02 , H04L25/03 , H04L25/30 , H04L27/01 , H04L27/38 , H03H7/30
CPC分类号： H04L25/03299 , H04L25/0218 , H04L25/0228
摘要： An equalization system for equalizing a corrupted signal is disclosed. The equalization system includes a complex matched filter (400) and a maximum likelihood sequence estimator (MLSE) (405) for removing the effects of phase shift, amplitude variations, intersymbol interference, etc. resulting from multi-pathing and noise contributed by the receiver front end. The system estimates a correlation signal C(t) (505) and synchronizes C(t) 505 to maximize its energy as seen on the taps of the complex matched filter (400). Taps having amplitude coefficients below a predetermined threshold are set to zero to produce a modified CIR estimate. The modified CIR estimate which has had the effects of noise virtually eliminated, is then used to construct the complex matched filter (400) and is also used as input to the MLSE (405) to produce a better equalized data signal.
摘要翻译：公开了一种用于均衡损坏信号的均衡系统。均衡系统包括复数匹配滤波器（400）和最大似然序列估计器（MLSE）（405），用于消除由接收机所贡献的多路径和噪声产生的相移，幅度变化，符号间干扰等的影响前端。系统估计相关信号C（t）（505）并使C（t）505同步以使复合匹配滤波器（400）的抽头上看到的能量最大化。具有低于预定阈值的幅度系数的抽头被设置为零以产生经修改的CIR估计。然后，使用已经具有噪声影响的修正的CIR估计来构造复匹配滤波器（400），并且还用作MLSE（405）的输入以产生更好的均衡数据信号。

37. 发明公开

US20230224103A1 INFRASTRUCTURE EQUIPMENT, COMMUNICATIONS DEVICES AND METHODS 审中-公开
公开(公告)号：US20230224103A1
公开(公告)日：2023-07-13
申请号：US18014474
申请日：2021-07-26
申请人： Sony Group Corporation
发明人： Samuel Asangbeng ATUNGSIRI
IPC分类号： H04L5/00 , H04L25/02
CPC分类号： H04L5/0012 , H04L5/001 , H04L25/0224 , H04L25/0218
摘要： Infrastructure equipment forming part of a wireless communications network configured to receive data from a communications device via a communications channel between the infrastructure equipment and the communications device. The infrastructure equipment comprises circuitry configured to receive, from the communications device, a request for a resource allocation, to receive one or more reference symbols from the communications device, to estimate based on the received reference symbols, for each of a plurality of resource units, RUs, of the communications channel, a signal to interference and noise ratio, SINR, sequence of the communications channel, and to perform a first transform followed by a second transform on the SINR sequence to produce a cepstrum of the SINR sequence, the second transform being an inverse of the first transform, and to encode and to transmit the cepstrum to the communications device.

38. 发明申请

US20190238386A1 METHOD FOR UPLINK MULTIUSER DATA TRANSMISSION AND SYSTEM FOR UPLINK MULTIUSER MULTIPLE INPUT MULTIPLE OUTPUT 审中-公开
公开(公告)号：US20190238386A1
公开(公告)日：2019-08-01
申请号：US16378160
申请日：2019-04-08
申请人： Huawei Technologies Co., Ltd.
发明人： Xun YANG , Yi LUO
IPC分类号： H04L27/26 , H04L25/02 , H04B7/06 , H04B7/08 , H04B7/0452
CPC分类号： H04L27/2695 , H04B7/0452 , H04B7/066 , H04B7/0848 , H04L25/0204 , H04L25/0218 , H04L25/0224 , H04L27/2602 , H04L27/2649
摘要： A method for uplink multiuser data transmission and a system for uplink multiuser multiple input multiple output are provided. The method implemented by an access point (AP) includes: sending, indication information to at least two stations (STAs), wherein the indication information indicates that the at least two STAs perform an uplink multiuser data transmission; receiving, uplink data sent by the at least two STAs through channels, respectively; and demodulating, the uplink data using receiving beams corresponding to pre-estimated channels, respectively. According to the embodiments of the present disclosure, the AP receives the uplink data from multiple STAs through different channels from the STAs to the AP respectively, and demodulates data using the receiving beams corresponding to the channels respectively, thereby realizing that the AP performs separation and demodulation of the uplink data sent by multiple STAs and realizing the uplink multiuser data transmission.

39. 发明申请

US20180183627A1 Method and Device for Estimating Frequency Offset 审中-公开
公开(公告)号：US20180183627A1
公开(公告)日：2018-06-28
申请号：US15756587
申请日：2016-05-25
申请人： ZTE CORPORATION
发明人： Jidong WEI
IPC分类号： H04L25/02 , H04L27/26 , H04L27/00 , H04B1/7103 , H04W56/00
CPC分类号： H04L25/0228 , H04B1/7103 , H04L25/0218 , H04L27/0014 , H04L27/2657 , H04L27/2672 , H04L27/2675 , H04L27/2695 , H04W56/0035
摘要： The present disclosure discloses a method and apparatus for estimating a frequency offset. The method includes: reconstructing an estimated channel value of a target user and an estimated channel value of a non-target user to obtain a reconstructed estimated channel value of the target user and a reconstructed estimated channel value of the non-target user; calculating frequency domain received data of a target user's local pilot frequency at which interference has been cancelled by using frequency domain data of a subcarrier occupied by the target user, frequency domain data of a subcarrier occupied by the adjacent non-target user, and the reconstructed estimated channel value of the target user and the reconstructed estimated channel value of the non-target user; and determining an estimated frequency offset value by using the target user's local pilot frequency at which interference has been cancelled and the frequency domain received data.

40. 发明授权

US09742610B2 Adaptive channel prediction and mitigating interference in OFDM systems 有权
公开(公告)号：US09742610B2
公开(公告)日：2017-08-22
申请号：US15069312
申请日：2016-03-14
申请人： Intel Corporation
发明人： Bernard Arambepola , Parveen K. Shukla , Thushara Hewavithana
IPC分类号： H04L27/26 , H04L5/00 , H04L25/02 , H04L25/03
CPC分类号： H04L27/2646 , H04L5/0007 , H04L25/0218 , H04L25/022 , H04L25/0232 , H04L25/03343 , H04L27/2607 , H04L27/2613 , H04L27/2647 , H04L27/2665 , H04L27/2678
摘要： One embodiment provides an apparatus. The apparatus includes an optimization module configured to determine a guard interval remainder based, at least in part on a comparison of an allowable microreflection interference level and an actual microreflection interference level; and a windowing module configured to window an OFDM (orthogonal frequency division multiplexed) symbol utilizing the guard interval remainder. The apparatus may further include a channel estimator module configured to determine a predicted channel frequency response based, at least in part, on a probing symbol; and a pre-equalizer module configured to pre-equalize the OFDM symbol based, at least in part, on the predicted channel frequency response.

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