公开(公告)号：US07212594B2

公开(公告)日：2007-05-01

申请号：US11270037

申请日：2005-11-09

申请人： Huseyin Arslan ,  Ali S. Khayrallah

发明人： Huseyin Arslan ,  Ali S. Khayrallah

IPC分类号： H03D1/04

CPC分类号： H04L25/03006 ,  H04L25/03267 ,  H04L25/03993 ,  H04L2025/03426 ,  H04W56/001 ,  H04W92/10

摘要： Methods and apparatus for canceling co-channel interference in a receiving system using spatio-temporal whitening. In some embodiments, a spatio-temporal interference canceling method, and apparatus for carrying out the method are provided which effectively cancel co-channel interference despite frequency offset between the desired signal and the interferer in a TDMA type system. Real and imaginary component values of the total received signal are used for virtual diversity branches, and a vector-valued auto regressive model is used to characterize the interference. In other embodiments, spatio-temporal interference whitening is used to improve timing estimates used for synchronization. The two uses of spatio-temporal whitening can be combined in one receiver. The invention is typically implemented in one or more programmed digital signal processors or application specific integrated circuits (ASICS), embodied in a receiving system.

摘要翻译： 用于消除接收系统中使用时空增白的同信道干扰的方法和装置。 在一些实施例中，提供了时空干扰消除方法以及用于执行该方法的装置，尽管TDMA类型系统中的期望信号和干扰信号之间的频率偏移，仍能有效地消除同信道干扰。 总接收信号的实分量值和虚分量值用于虚拟分集分支，并且使用向量值自回归模型来表征干扰。 在其它实施例中，使用空间 - 时间干扰白化来改善用于同步的定时估计。 时空白化的两种用途可以组合在一个接收器中。 本发明通常在一个或多个编程的数字信号处理器或专用集成电路（ASICS）中实施，体现在接收系统中。

公开(公告)号：US06738481B2

公开(公告)日：2004-05-18

申请号：US09757962

申请日：2001-01-10

申请人： Leonid Krasny ,  Ali S. Khayrallah

发明人： Leonid Krasny ,  Ali S. Khayrallah

IPC分类号： H04B1500

CPC分类号： G10L21/0208 ,  G10L2021/02166

摘要： A method and noise reduction apparatus comprises a microphone array including a plurality of microphone elements for receiving a training signal including a plurality of training signal samples, and a working signal including a plurality of working signal samples, and at least one frequency domain convertor coupled to the plurality of microphone elements for converting the plurality of training signal samples and the plurality of working signal samples to the frequency domain. A signal spatial correlation matrix estimator is coupled to the at least one frequency domain convertor for estimating a signal spatial correlation matrix using the converted plurality of training signal samples. An inverse noise spatial correlation matrix estimator is coupled to the at least one frequency domain convertor for estimating an inverse noise spatial correlation matrix using the converted plurality of working signal samples. A constrained output generator is coupled to the at least one frequency domain convertor, the signal spatial correlation matrix estimator and the inverse noise spatial correlation matrix estimator for generating a constrained output for the noise reduction apparatus using the converted working signal samples, the estimated signal spatial correlation matrix and the estimated inverse noise spatial correlation matrix.

摘要翻译： 一种方法和降噪装置包括麦克风阵列，其包括多个麦克风元件，用于接收包括多个训练信号样本的训练信号，以及包括多个工作信号采样的工作信号，以及至少一个频域转换器， 所述多个麦克风元件用于将所述多个训练信号样本和所述多个工作信号样本转换成所述频域。 信号空间相关矩阵估计器耦合到所述至少一个频域转换器，用于使用所转换的多个训练信号采样来估计信号空间相关矩阵。 反相噪声空间相关矩阵估计器被耦合到所述至少一个频域转换器，用于使用所转换的多个工作信号采样来估计逆噪声空间相关矩阵。 约束输出发生器耦合到至少一个频域转换器，信号空间相关矩阵估计器和反相噪声空间相关矩阵估计器，用于使用转换的工作信号采样来生成用于降噪装置的约束输出，估计信号空间 相关矩阵和估计的反噪声空间相关矩阵。

公开(公告)号：US06697441B1

公开(公告)日：2004-02-24

申请号：US09587995

申请日：2000-06-06

申请人： Gregory Edward Bottomley ,  Paul Wilkinson Dent ,  Ali S. Khayrallah ,  Huseyin Arslan

发明人： Gregory Edward Bottomley ,  Paul Wilkinson Dent ,  Ali S. Khayrallah ,  Huseyin Arslan

IPC分类号： H04L2722

CPC分类号： H03M13/2957 ,  H03M13/2707 ,  H03M13/2721 ,  H03M13/3905 ,  H03M13/6325 ,  H03M13/6331 ,  H04L1/005 ,  H04L1/0071 ,  H04L25/03171 ,  H04L25/03318 ,  H04L25/03337 ,  H04L25/067 ,  H04L27/22 ,  H04L27/38

摘要： Received signals are decoded based on a coupling between bits of the received signals introduced by the channel over which the signal is transmitted or by the transmitter which transmitted the signals. For example, in a higher-order modulation scheme, such as 8-PSK, individual bits grouped in a given symbol are generally coupled rather than fully independent. Accordingly, decoding information on a first one of the bits processed through a forward error correction decoder may be used to adjust the soft information from a demodulator for one or more of the other bits contained in the same symbol for use in processing those bits through the forward error correction decoder. Particularly where interleaving is utilized, a first bit may be processed through the decoder before the soft information on another of the bits is needed, thereby allowing an intermediate decision soft value for the first bit to be used in generating the input value to the decoder for the subsequent bit. Alternatively, a multi-pass process may be utilized which may allow all of the bits to be decoded utilizing soft information from the first decoding pass to affect the input to the decoder during the second pass for coupled bits such as those transmitted in a common symbol.

摘要翻译： 接收信号基于由发送信号的信道所引入的接收信号的位之间的耦合或通过发送信号的发送器进行解码。 例如，在诸如8-PSK的更高阶调制方案中，分组在给定符号中的各个比特通常耦合而不是完全独立的。 因此，可以使用通过前向纠错解码器处理的比特中的第一个比特的解码信息来从解调器调整包含在相同符号中的一个或多个其他比特的软信息，以用于通过 前向纠错解码器。 特别是在使用交织的情况下，可以在需要对另一位的软信息之前通过解码器处理第一位，从而允许将第一位的中间判定软值用于向译码器生成输入值 随后的一点。 或者，可以使用多遍处理，其可以利用来自第一解码通过的软信息来解码所有比特，以在第二遍期间影响到解码器的输入，用于耦合比特，例如以公共符号 。

公开(公告)号：US06490314B1

公开(公告)日：2002-12-03

申请号：US09158996

申请日：1998-09-23

申请人： Ali S. Khayrallah ,  Kumar Balachandran

发明人： Ali S. Khayrallah ,  Kumar Balachandran

IPC分类号： H04B1713

CPC分类号： H04B1/707 ,  H04B1/71 ,  H04B1/713

摘要： The present invention relates to methods and systems for wireless communication wherein a plurality of narrowband carrier frequencies is overlaid with at least one wideband carrier frequency. In particular, the present invention relates to maintaining radio communication on the narrowband carrier frequencies closest to the edge of the bandwidth of the wideband carrier frequency in order to reduce system interference. This is accomplished by using frequency hopping to preferentially switch radio communication to narrowband carrier frequencies closest to the edge of the bandwidth of the wideband carrier frequency. Thus, the present invention discloses systems and methods which allow several communication devices to occupy the same frequency spectrum while maintaining interference at acceptable levels.

摘要翻译： 本发明涉及用于无线通信的方法和系统，其中多个窄带载波频率覆盖有至少一个宽带载波频率。 特别地，本发明涉及在最宽的宽带载波频带边缘的窄带载频上维持无线电通信，以减少系统干扰。 这通过使用跳频来优先地将无线电通信切换到最接近宽带载波带宽边缘的窄带载波来实现。 因此，本发明公开了允许多个通信设备占据相同频谱同时保持可接受水平的干扰的系统和方法。

公开(公告)号：US06381713B1

公开(公告)日：2002-04-30

申请号：US09309352

申请日：1999-05-11

申请人： David Rand Irvin ,  Ali S. Khayrallah

发明人： David Rand Irvin ,  Ali S. Khayrallah

IPC分类号： G06F1100

CPC分类号： H04L1/0057 ,  H04L1/18 ,  H04L2001/0098

摘要： In a digital communication system, a method is provided for recognizing and acting upon differences in information field characteristics when transmission errors are detected. Information having more than one field protected by a channel code is received and decoded according to the channel code. Based on the outcome of the decoding, fields of the information into which transmission errors fall are identified. These are called flawed fields. A characteristic of a flawed field is determined. The information is then processed according to the characteristic. In one embodiment of the invention, the syndrome of an incoming packet is computed. When the syndrome is all-zero, the packet is passed up a communication protocol stack conventionally. When the syndrome is not all-zero, the coset leader associated with the syndrome is found, and used to determine which fields of the packet are most likely flawed. Based on this determination, the packet is then rejected, corrected, or accepted without correction, according to the following method: When a critical field of the packet header is flawed, the packet is rejected. Otherwise, the packet is passed up the protocol stack with its transmission errors corrected or uncorrected, depending on the importance of the fields into which transmission errors fall.

摘要翻译： 在数字通信系统中，提供了一种在检测到传输错误时识别和对信息场特性的差异起作用的方法。 具有由信道码保护的多于一个场的信息根据信道码被接收和解码。 基于解码的结果，识别发送错误落入的信息的字段。 这些被称为有缺陷的领域。 确定有缺陷的场的特征。 然后根据特征处理信息。 在本发明的一个实施例中，计算输入分组的校验子。 当综合征全为零时，分组通常传递通信协议栈。 当综合征不是全零时，发现与综合征相关联的陪集领导，并用于确定分组的哪些字段最有可能是有缺陷的。 根据这一判断，根据以下方法，将数据包拒绝，纠正或接受，无需更正：当数据包头的关键字段有缺陷时，数据包被拒绝。 否则，根据发送错误所在的字段的重要性，将数据包传递到其传输错误被校正或未校正的协议栈中。

公开(公告)号：US06263030B1

公开(公告)日：2001-07-17

申请号：US09108520

申请日：1998-07-01

申请人： Ali S. Khayrallah

发明人： Ali S. Khayrallah

IPC分类号： H03D100

CPC分类号： H04L1/0059 ,  H04L1/0047 ,  H04L1/0054 ,  H04L1/0061 ,  H04L25/0202

摘要： An equalizer is provided for use in a mobile radio communication system for compensating for changing channel conditions caused by movement of a mobile communication device at varying speeds. The equalizer includes an estimator receiving a digital signal transmitted over a communication channel, the digital signal being adversely modified by fading during transmission caused by movement of the mobile communication device at varying speeds, and a channel estimate signal, the estimator responsively producing a decision signal representing an approximation of the transmitted digital signal with fading eliminated. First and second channel trackers are provided, each tuned to a different speed of the mobile communication device and each receiving the decision signal. A decision circuit receives the decision signal and responsively selects one of the first and second channel trackers to produce the channel estimate signal.

摘要翻译： 提供了一种用于移动无线电通信系统中的均衡器，用于补偿由移动通信设备以不同速度的移动引起的改变的信道状况。 均衡器包括接收通过通信信道发送的数字信号的估计器，通过移动通信设备以变化的速度的移动引起的传输期间的衰落被不利地修改的数字信号，以及信道估计信号，该估计器响应地产生判决信号 代表消除了衰落的发射数字信号的近似值。 提供了第一和第二通道跟踪器，每个跟踪器被调谐到移动通信设备的不同速度，并且每个接收决定信号。 决定电路接收判定信号，并且响应地选择第一和第二信道跟踪器中的一个以产生信道估计信号。

公开(公告)号：US06216107B1

公开(公告)日：2001-04-10

申请号：US09174207

申请日：1998-10-16

申请人： Nils Rydbeck ,  R. David Koilpillai ,  Ali S. Khayrallah ,  Tracy Fulghum

发明人： Nils Rydbeck ,  R. David Koilpillai ,  Ali S. Khayrallah ,  Tracy Fulghum

IPC分类号： G10L1900

CPC分类号： H04L1/0059 ,  H04L1/007 ,  H04L1/08 ,  H04L2025/03566

摘要： In a transmitter for transmitting communication signals across a radio channel, an improved encoder includes a half-rate encoder receiving a digitized speech signal and generating a compressed bit stream at half-rate, and a signal expander receiving the compressed bit stream and generating an expanded bit stream at full-rate for transmission across a radio channel. An improved receiver, receives the transmitted communication signal which is selected from the group consisting of (a) a conventional full-rate encoded digitized speech signal, and (b) a half-rate encoded digitized speech signal including the expanded bit stream. The improved receiver includes a full-rate equalizer, a half-rate equalizer, and a switch initially routing the received digitized speech signal to the full-rate equalizer, wherein the full-rate equalizer demodulates the received digitized speech signal producing a full-rate demodulated signal and dibits of soft information corresponding to the full-rate demodulated signal. An analyzer analyzes the dibits of soft information and controls the switch to route the received digitized speech signal to one of the full-rate and half-rate equalizers based upon the analysis.

公开(公告)号：US6005899A

公开(公告)日：1999-12-21

申请号：US939517

申请日：1997-09-29

申请人： Ali S. Khayrallah

发明人： Ali S. Khayrallah

IPC分类号： G06F17/15 ,  H03D1/00

CPC分类号： G06F17/15

摘要： An improved method for computing sequence correlations utilizes pre-calculated look-up tables to reduce computational burdens. A sample sequence of symbols, such as a received sequence of symbols, is divided into a series of subblocks. A look-up table of combinational values is built for each subblock wherein the combinational values are arithmetic sums of the symbols in the subblock, either as received or negated. Preferably, the combinational values are computed in Gray code order so as to take advantage of bit-shifting and sign changes to lessen computational burdens. Correlation factors with respect to a known sequence of symbols are then calculated using the combinational values from these pre-calculated tables whenever possible. The correlation factors are then used in a known fashion to reach a correlation result. This method increase correlation computational efficiency in many situations, particularly for joint demodulation, code acquisition, and/or interference cancellation in wireless communications systems.

摘要翻译： 用于计算序列相关性的改进方法利用预先计算的查找表来减少计算负担。 诸如接收的符号序列之类的符号序列被分成一系列子块。 为每个子块构建组合值的查找表，其中组合值是子块中符号的算术和，无论是接收还是否定。 优选地，组合值以格雷码顺序计算，以利用位移和符号改变来减轻计算负担。 然后，使用来自这些预先计算的表的组合值来计算相对于已知序列符号的相关因子。 然后以已知方式使用相关因子以达到相关结果。 这种方法在许多情况下增加了相关计算效率，特别是对于无线通信系统中的联合解调，代码获取和/或干扰消除。

公开(公告)号：US5920597A

公开(公告)日：1999-07-06

申请号：US714684

申请日：1996-09-16

申请人： Ali S. Khayrallah ,  Amer Hassan

发明人： Ali S. Khayrallah ,  Amer Hassan

IPC分类号： H03M13/39 ,  H03M13/41 ,  H04L1/00 ,  H04L27/00 ,  H04L27/22 ,  H04L23/02 ,  H04L5/12

CPC分类号： H03M13/6502 ,  H03M13/4123 ,  H03M13/413 ,  H04L1/0054

摘要： A method for decoding encoded digital data. A decoder generates a replicated decoding trellis and performs some number D.sup.max of decoding operations using the replicated trellis. Each decoding pass is offset by some amount .delta., and the results of each pass are stored and compared with prior results to generate a final output information sequence.

摘要翻译： 一种解码编码数字数据的方法。 解码器产生复制解码网格，并使用复制网格执行解码操作的一些数量D max。 每个解码通过偏移一定量的增量，并且每个遍的结果被存储并与先前的结果进行比较以产生最终的输出信息序列。

公开(公告)号：US5745502A

公开(公告)日：1998-04-28

申请号：US723217

申请日：1996-09-27

申请人： Ali S. Khayrallah ,  David R. Irvin

发明人： Ali S. Khayrallah ,  David R. Irvin

IPC分类号： H03M13/09 ,  G06F11/10 ,  G11B20/18 ,  H03M13/00 ,  H03M13/03 ,  H04L1/00 ,  H04L1/16 ,  H04L1/18 ,  H04L1/02 ,  H04L1/08

CPC分类号： H03M13/093 ,  G11B20/1803 ,  H04L1/1628 ,  H04L1/18 ,  H04L1/1812 ,  H04L1/1838 ,  H04L1/1845 ,  H04L1/188 ,  H04L1/0001 ,  H04L1/1806 ,  H04L1/1809 ,  H04L1/1877 ,  H04L2001/0093

摘要： A method of error correction for an ARQ system allows decoding when an even number of flawed packets are received. Multiple flawed replications of a transmitted bit sequence are compared bit-by-bit. A set of composite packets is formed containing all possible combinations of values at the disputed bit positions. A validity check is performed on each of the composite packets. If only a single composite packet passes the validity check, an acknowledgment signal is sent.

摘要翻译： ARQ系统的纠错方法允许在接收到偶数个有缺陷的数据包时进行解码。 对发送的比特序列的多个有缺陷的复制进行比较。 形成一组复合数据包，其中包含有争议的位位置的值的所有可能的组合。 对每个复合数据包执行有效性检查。 如果只有单个复合分组通过有效性检查，则发送确认信号。