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1. 发明授权

US07092436B2 Expectation-maximization-based channel estimation and signal detection for wireless communications systems 有权
公开(公告)号：US07092436B2
公开(公告)日：2006-08-15
申请号：US10057179
申请日：2002-01-25
申请人： Xiaoqiang Ma , Hisashi Kobayashi , Stuart C. Schwartz , Daqing Gu , Jinyun Zhang
发明人： Xiaoqiang Ma , Hisashi Kobayashi , Stuart C. Schwartz , Daqing Gu , Jinyun Zhang
IPC分类号： H03H7/30 , H03H7/40
CPC分类号： H04L25/0242 , H04L25/0204 , H04L25/0224 , H04L27/2647
摘要： A system and method detect symbols of a modulated signal received via a plurality of channels of a wireless communications system. A symbol transmitted via the channels is initially estimated based on the channel estimate from either pilot symbol or previously estimated symbol, and then channel estimate is updated. The next estimate of the symbol is computed by using updated channel information and maximizing the expectation of the log likelihood function. The next estimate is then quantized according to the signal constellation. The quantized estimate of the symbol is compared with the previous estimate of the symbol to determine if the previous estimate of the symbol and the quantized next estimate of the symbol have converged. Otherwise, the quantized next estimate of the symbol is made as the input for the next iteration, and the updating, optimizing, quantizing, and comparing are repeated until the estimate converges.

2. 发明授权

US06930637B2 Method and apparatus for high resolution tracking via mono-pulse beam-forming in a communication system 有权
标题翻译：用于在通信系统中通过单脉冲波束成形进行高分辨率跟踪的方法和装置
公开(公告)号：US06930637B2
公开(公告)日：2005-08-16
申请号：US10293834
申请日：2002-11-13
申请人： Louis R. Brothers, Jr. , John Cangeme , Alexander Flaig , Samuel J. MacMullen , H. Vincent Poor , Tandhoni S. Rao , Stuart C. Schwartz , Triveni N. Upadhyay
发明人： Louis R. Brothers, Jr. , John Cangeme , Alexander Flaig , Samuel J. MacMullen , H. Vincent Poor , Tandhoni S. Rao , Stuart C. Schwartz , Triveni N. Upadhyay
IPC分类号： G01S3/32 , H01Q25/02 , H04B7/06 , H04B7/08 , G01S5/02 , H01Q3/16
CPC分类号： G01S3/32 , H01Q25/02 , H04B7/0617 , H04B7/086
摘要： Method and apparatus for high resolution tracking via mono-pulse beam-forming in a communication system in which the capacity and range of mobile or fixed wireless communication base stations are improved by implementing a single or multiple antenna beam per signal path. Adaptive beam-forming based on up-link direction-of arrival estimation can be performed without using the above-mentioned computationally intensive techniques.
摘要翻译：在通信系统中通过单脉冲波束形成进行高分辨率跟踪的方法和装置，其中移动或固定无线通信基站的容量和范围通过每个信号路径实现单个或多个天线波束来改善。可以在不使用上述计算密集技术的情况下执行基于上行链接到达方向估计的自适应波束形成。

3. 发明授权

US06400761B1 Method and apparatus for adaptively compensating channel or system variations in precoded communications system 失效
标题翻译：用于自适应地补偿预编码通信系统中的信道或系统变化的方法和装置
公开(公告)号：US06400761B1
公开(公告)日：2002-06-04
申请号：US09591828
申请日：2000-06-12
申请人： John E. Smee , Stuart C. Schwartz
发明人： John E. Smee , Stuart C. Schwartz
IPC分类号： H03H730
CPC分类号： H04L25/03343 , H04L25/03057 , H04L2025/0349 , H04L2025/03662 , H04L2025/03808
摘要： The present invention relates to a method and apparatus for adaptively compensating for channel or system variations in which adaptive compensation is used in the receiver of a digital communication system. The transmitter of the digital communication system includes precoding. The adaptive receiver compensation mitigates the interferences not removed by the transmitter precoder. In an embodiment of the invention, the adaptive compensation can be performed using an adaptive feedforward filter (FFF) and a feedback filter (FBF) in the receiver. The FBF output is generated based on previous values of estimates of the transmitted precoded sequence. The determined value of the FBF coefficients can be periodically relayed to the transmitter to update the precoder coefficients of the transmitter. Alternatively, the value of the FBF coefficients can be relayed to the transmitter after the value of the coefficients exceeds a predetermined threshold. Accordingly, the receiver adaptively and automatically compensates for misadjustments of the fixed transmitter precoder with respect to the actual channel at a given point in time.
摘要翻译：本发明涉及用于自适应地补偿在数字通信系统的接收机中使用自适应补偿的信道或系统变化的方法和装置。数字通信系统的发射机包括预编码。自适应接收机补偿减轻了发射机预编码器未被去除的干扰。在本发明的实施例中，可以使用接收机中的自适应前馈滤波器（FFF）和反馈滤波器（FBF）来执行自适应补偿。基于传输的预编码序列的估计值的先前值来生成FBF输出。可以将确定的FBF系数的值周期性地中继到发射机，以更新发射机的预编码器系数。或者，在系数值超过预定阈值之后，可以将FBF系数的值中继到发射机。因此，接收机在给定时间点自适应地且自动地补偿固定发射机预编码器相对于实际信道的误调整。

4. 发明授权

US5715325A Apparatus and method for detecting a face in a video image 失效
标题翻译：用于检测视频图像中的脸部的装置和方法
公开(公告)号：US5715325A
公开(公告)日：1998-02-03
申请号：US521175
申请日：1995-08-30
申请人： Richard D. Bang , Ming Fang , Stuart C. Schwartz , Keith M. Andress
发明人： Richard D. Bang , Ming Fang , Stuart C. Schwartz , Keith M. Andress
IPC分类号： G06K9/00
CPC分类号： G06K9/00228
摘要： A detection system identifies a person by rapidly analyzing an image frame from a video camera for the presence of a face by reducing the image in resolution and normalizing the image to compensate for lighting changes and compares the normalized image with a background image to produce a binary interest mask. The most likely position of a face is then determined by identifying a top, bottom and sides of a possible head region to define a bounding box, normalizing the pixel data within the bounding box to further compensate for lighting variations, and resizing the box to match identification templates stored in memory. The best match from the identification templates is provided with a score indicative of the degree of the match. If the score does not exceed a first score threshold, then no face is assumed present. If the score exceeds a first and second score threshold, then a face is assumed present. If the first score threshold is exceeded but the second is not, a further eye location procedure is performed on the data to determine if a face is present.
摘要翻译：检测系统通过以分辨率降低图像并对图像进行归一化以补偿照明变化并通过将归一化图像与背景图像进行比较来快速分析来自摄像机的图像帧以识别脸部的存在，从而产生二进制兴趣面具然后通过识别可能的头部区域的顶部，底部和侧面来定义边界框来确定面部的最可能的位置，对边界框内的像素数据进行归一化以进一步补偿照明变化，并且调整框以匹配识别模板存储在内存中。来自识别模板的最佳匹配被提供有指示匹配程度的得分。如果分数不超过第一分数阈值，则假定不存在面。如果分数超过第一和第二分数阈值，则假定存在脸部。如果超过了第一分数阈值，但第二分数不是，则对该数据执行进一步的眼睛定位过程以确定面部是否存在。

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