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1. 发明授权

US6108517A Methods and apparatus for joint demodulation of adjacent channel signals in digital communications systems 失效
标题翻译：数字通信系统中相邻信道信号联合解调的方法和装置
公开(公告)号：US6108517A
公开(公告)日：2000-08-22
申请号：US901694
申请日：1997-07-28
申请人： Huseyin Arslan , Someshwar C. Gupta , Gregory E. Bottomley , Sandeep Chennakeshu
发明人： Huseyin Arslan , Someshwar C. Gupta , Gregory E. Bottomley , Sandeep Chennakeshu
IPC分类号： H04J1/12 , H04B1/10 , H04B7/26 , H04L25/02 , H04L25/03 , H04Q7/36 , H04B7/10
CPC分类号： H04L25/03331 , H04L25/0204
摘要： Methods and apparatus for receiving adjacent channel signals wherein adjacent channel interference effects are minimized through joint demodulation of the adjacent channel signals. A channel associated with each signal and each corresponding frequency band is estimated and used to form joint branch metrics for joint sequence estimation. In an exemplary embodiment, a baseband processor receives baseband samples corresponding to at least one carrier frequency, and then jointly demodulates at least two information streams corresponding to different carrier frequencies in dependence upon the received baseband samples. In another embodiment, a joint channel estimator receives at least two baseband sample streams, each stream corresponding to a different frequency band, and jointly estimates medium responses for each of at least two information signals which were transmitted in different frequency bands.
摘要翻译：用于接收相邻信道信号的方法和装置，其中相邻信道干扰效应通过相邻信道信号的联合解调被最小化。与每个信号和每个对应的频带相关联的信道被估计并用于形成用于联合序列估计的联合分支度量。在示例性实施例中，基带处理器接收对应于至少一个载波频率的基带采样，然后根据所接收的基带采样，共同解调对应于不同载波频率的至少两个信息流。在另一个实施例中，联合信道估计器接收对应于不同频带的每个流的至少两个基带采样流，并联合估计在不同频带中发送的至少两个信息信号中的每一个的媒体响应。

2. 发明授权

US06212368B1 Measurement techniques for diversity and inter-frequency mobile assisted handoff (MAHO) 失效
标题翻译：用于分集和频间移动辅助切换（MAHO）的测量技术
公开(公告)号：US06212368B1
公开(公告)日：2001-04-03
申请号：US09085528
申请日：1998-05-27
申请人： Rajaram Ramesh , Sandeep Chennakeshu , Gregory E. Bottomley
发明人： Rajaram Ramesh , Sandeep Chennakeshu , Gregory E. Bottomley
IPC分类号： H04B1700
CPC分类号： H04W88/02 , H04B7/0808 , H04W24/10 , H04W36/06
摘要： Diversity and inter-frequency mobile-assisted handoff (MAHO) are achieved under continuous reception cellular access methods by using strategic timing and switching optimizations. Strategic timing is achieved by avoiding the non-reception of power control bits. For example, the mobile terminal can make measurements for diversity in the last eight bits of a sub-frame of an IS-95 downlink transmission. Switching is optimized, for example, by storing rake taps for a first antenna prior to switching to a second antenna so that the rake tap positions can be restored upon returning to the first antenna. With these and other disclosed measurement techniques, the benefits of diversity and inter-frequency MAHO can be achieved in continuous reception cellular systems.
摘要翻译：通过使用战略定时和切换优化，在连续接收蜂窝接入方式下实现分集和频间移动辅助切换（MAHO）。通过避免电源控制位的不接收来实现战略时序。例如，移动终端可以对IS-95下行链路传输的子帧的最后8位中的分集进行测量。优化切换，例如，在切换到第二天线之前，通过存储用于第一天线的雷击抽头，使得在返回到第一天线时可以恢复前叉抽头位置。利用这些和其他公开的测量技术，可以在连续接收蜂窝系统中实现分集和频间MAHO的益处。

3. 发明授权

US6005887A Despreading of direct sequence spread spectrum communications signals 失效
标题翻译：直接序列扩频通信信号的解扩
公开(公告)号：US6005887A
公开(公告)日：1999-12-21
申请号：US748755
申请日：1996-11-14
申请人： Gregory E. Bottomley , Rajaram Ramesh , Paul W. Dent , Sandeep Chennakeshu
发明人： Gregory E. Bottomley , Rajaram Ramesh , Paul W. Dent , Sandeep Chennakeshu
IPC分类号： H04B7/26 , H04B1/707 , H04B1/709 , H04B15/00 , H04K1/00 , H04L27/30
CPC分类号： H04B1/709 , H04B1/707
摘要： The disclosure presents a number of reduced complexity architectures for despreading direct sequence spread spectrum communications signals. In a first despreading architecture for a sequence removal unit, received chip-spaced complex samples are negated in accordance with the processed phase of a complex spreading sequence. Furthermore, the in-phase and quadrature phase sample values are switched for each other in accordance with the processed phase. In a second despreading architecture, in a sequence removal unit, received chip-spaced complex samples are processed in the logarithmic domain, with the phase of the complex spreading sequence added to the detected phase, and the resulting complex signal then converted back to Cartesian coordinates. In a third despreading architecture for a correlator, sequence removal and correlation are performed in the logarithmic domain with the amplitudes and phases for the resulting complex signal arithmetically averaged and then converted back to Cartesian coordinates. architecture also for a correlator, sequence removal and correlation are performed in the logarithmic domain using circular averaging. In a fifth despreading architecture also for a correlator, wherein multiple component sequences are combined together to form an overall sequence, and wherein one of the multiple component sequences is shared by all channels, a common sequence removal is provided for removal of the shared sequence from all channels. The resulting signals are then sent to a plurality of individual correlators for removal of channel specific sequences.
摘要翻译：本公开提出了用于解扩直接序列扩频通信信号的许多降低的复杂度架构。在用于序列去除单元的第一解扩架构中，根据复扩展序列的处理相位，接收的码片间隔复数样本被否定。此外，同相和正交相位采样值根据处理相位彼此切换。在第二解扩架构中，在序列去除单元中，在对数域中处理接收的码片间隔复数样本，其中复扩展序列的相位被加到检测相位，并且所得到的复信号然后转换回笛卡尔坐标。在用于相关器的第三解扩架构中，在对数域中执行序列去除和相关，其中所得复数信号的幅度和相位被算术平均，然后转换回笛卡尔坐标。用于相关器的架构，使用循环平均在对数域中执行序列去除和相关。在用于相关器的第五解扩架构中，其中将多个分量序列组合在一起以形成整个序列，并且其中所述多个分量序列之一由所有信道共享，提供共同的序列去除以从所有频道然后将所得到的信号发送到多个单独的相关器，以去除信道特定序列。

4. 发明授权

US07099410B1 Reduced complexity MLSE equalizer for M-ary modulated signals 失效
标题翻译：降低复杂度MLSE均衡器用于M-ary调制信号
公开(公告)号：US07099410B1
公开(公告)日：2006-08-29
申请号：US09237356
申请日：1999-01-26
申请人： Sandeep Chennakeshu , Kambiz Zangi , Gregory E. Bottomley
发明人： Sandeep Chennakeshu , Kambiz Zangi , Gregory E. Bottomley
IPC分类号： H04L27/06
CPC分类号： H04L25/03197 , H04L25/03299
摘要： The present invention involves demodulation of radio signals modulated with M-ary modulation in the presence of intersymbol interference distortion. The invention presents a method for reducing the number of multiplications needed to implement a maximum-likelihood-sequence-estimation (MLSE) equalizer for signals modulated with M-ary modulation. In exemplary embodiments of the present invention, the number of multiplications is reduced by pre-computing certain values needed for the determination of the branch metric and storing these pre-computed values in a product table. When a branch metric computation is to be made, whether it is an Euclidean branch metric computation or an Ungerboeck branch metric computation, certain multiplication operations are replaced by simple table look-up operations. As a result, the power efficiency and speed of the system are increased. Any receiver that demodulates signals that are modulated with M-ary modulation can be implemented using the present invention. The resulting demodulator will have a lower complexity than existing demodulators.
摘要翻译：本发明涉及在存在符号间干扰失真的情况下解调用M进制调制的无线电信号。本发明提出了一种用于减少对用M-ary调制调制的信号实现最大似然序列估计（MLSE）均衡器所需的乘法次数的方法。在本发明的示例性实施例中，通过预先计算确定分支度量所需的某些值并将这些预先计算的值存储在产品表中来减少乘法次数。当进行分支度量计算时，无论是欧几里德分支度量计算还是Ungerboeck分支度量计算，某些乘法运算都被简单的表查找操作所取代。结果，系统的功率效率和速度增加。可以使用本发明来实现解调通过M进制调制调制的信号的任何接收机。所产生的解调器将具有比现有解调器更低的复杂度。

5. 发明授权

US6137843A Methods and apparatus for canceling adjacent channel signals in digital communications systems 失效
标题翻译：用于消除数字通信系统中相邻信道信号的方法和装置
公开(公告)号：US6137843A
公开(公告)日：2000-10-24
申请号：US901693
申请日：1997-07-28
申请人： Sandeep Chennakeshu , Rajaram Ramesh , Gregory E. Bottomley , Paul W. Dent
发明人： Sandeep Chennakeshu , Rajaram Ramesh , Gregory E. Bottomley , Paul W. Dent
IPC分类号： H04J1/00 , H01Q1/24 , H01Q21/08 , H01Q21/28 , H04B1/10 , H04B1/12 , H04B7/005 , H04B7/08 , H04B7/10 , H04B7/185 , H04B7/195 , H04B7/204 , H04B7/212 , H04B7/26 , H04J1/12 , H04J3/00 , H04L1/00 , H04L1/06 , H04L25/02 , H04L25/03 , H04W16/02 , H04W16/14 , H04W74/08 , H04W84/02 , H04W84/04 , H04W84/06 , H04L25/08
CPC分类号： H01Q1/246 , H01Q21/08 , H01Q21/28 , H04B1/126 , H04B7/0851 , H04B7/10 , H04B7/18513 , H04B7/18515 , H04B7/18532 , H04B7/18567 , H04B7/2041 , H04L1/06 , H04L25/0204 , H04L25/021 , H04L25/03331 , H04W16/02 , H04W84/025 , H04B7/0837 , H04L1/007 , H04L25/03203 , H04L25/0328 , H04L25/03299 , H04W16/14 , H04W74/08 , H04W84/042 , H04W84/06
摘要： A multi-signal cancelling demodulator in which signals of interest are demodulated using information obtained during demodulation of adjacent signals. By utilizing detected information in an across-channel fashion, exemplary cancelling demodulators provide superior adjacent channel interference rejection. The cancelling demodulation is conducted in either serial or parallel fashion. In exemplary parallel demodulation embodiments, two channels are demodulated simultaneously in iterative fashion. Detected information obtained at each step in the iterative process is used as a priori information for demodulation in a following step. In exemplary serial demodulation embodiments, the stronger of two received signals is demodulated, and the resulting detected information is used as a priori information for demodulation of the weaker of the two received signals. For both the serial and parallel demodulation embodiments, novel techniques are disclosed for transforming symbols detected in one frequency band to corresponding symbols in adjacent frequency bands. Such inter-channel transformations are also applied in the context of channel estimation. In an exemplary channel estimator, multiple channel parameter estimates for a particular frequency channel are provided based on a received baseband signal corresponding to that frequency channel. Since inter-channel information is used in providing the channel parameter estimates, the exemplary channel estimator provides superior adjacent channel interference rejection.
摘要翻译：一种多信号消除解调器，其中使用在相邻信号的解调期间获得的信息来解调感兴趣的信号。通过利用跨信道方式的检测信息，示例性的消除解调器提供了优越的相邻信道干扰抑制。取消解调以串行或并行方式进行。在示例性并行解调实施例中，两个信道以迭代方式同时被解调。在迭代处理中的每个步骤获得的检测信息被用作以下步骤中的解调的先验信息。在示例性串行解调实施例中，两个接收信号中的较强者被解调，并且所得到的检测信息被用作用于解调两个接收信号较弱的先验信息。对于串行和并行解调实施例，公开了用于将在一个频带中检测的符号变换为相邻频带中的相应符号的新颖技术。这样的信道间变换也在信道估计的上下文中应用。在示例性信道估计器中，基于对应于该频率信道的接收基带信号来提供针对特定频率信道的多信道参数估计。由于在提供信道参数估计中使用信道间信息，所以示例性信道估计器提供了优越的相邻信道干扰抑制。

6. 发明授权

US6134260A Method and apparatus for frequency acquisition and tracking for DS-SS CDMA receivers 失效
标题翻译：用于DS-SS CDMA接收机的频率采集和跟踪的方法和装置
公开(公告)号：US6134260A
公开(公告)日：2000-10-17
申请号：US991770
申请日：1997-12-16
申请人： Gregory E. Bottomley , Raymond L. Toy , Sandeep Chennakeshu , Karl J. Molnar
发明人： Gregory E. Bottomley , Raymond L. Toy , Sandeep Chennakeshu , Karl J. Molnar
IPC分类号： H04B1/7075 , H04B1/7085 , H04R15/00
CPC分类号： H04B1/7075 , H04B1/7085
摘要： Systems and methods for frequency acquisition and channel tracking in a direct sequence code division multiple access system are described. Frequency estimates are prepared and refined, which estimates are also used in the channel tracking process.
摘要翻译：描述了直接序列码分多址系统中频率采集和信道跟踪的系统和方法。频率估计被准备和改进，这些估计也用于信道跟踪过程。

7. 发明授权

US06768913B1 Method and apparatus for performing beam searching in a radio communication system 有权
公开(公告)号：US06768913B1
公开(公告)日：2004-07-27
申请号：US09583535
申请日：2000-06-01
申请人： Karl J. Molnar , Gregory E. Bottomley , Sandeep Chennakeshu
发明人： Karl J. Molnar , Gregory E. Bottomley , Sandeep Chennakeshu
IPC分类号： H04B138
CPC分类号： H04W16/28 , H04B7/18532
摘要： A radio communication system includes a base station having a directional antenna for generating a plurality of beams. A first set of the beams is used to receive signals which are decoded at the base station. A second set of the beams is used for interrogating a cell to identify beams which should be added to the first set of beams (for example, in response to mobile terminals entering the cell). In one embodiment, the second set of beams comprises a plurality of searcher beams produced by a fixed-beam phased array antenna. In a second embodiment, the second set of beams comprises a single searcher beam which is scanned through the cell by an adaptive phased array antenna. The radio communication system can be used to communicate with indoor mobile terminals through a plurality of radio heads, and also can be used to communicate with orbiting satellites.

8. 发明授权

US06694154B1 Method and apparatus for performing beam searching in a radio communication system 失效
标题翻译：在无线电通信系统中执行波束搜索的方法和装置
公开(公告)号：US06694154B1
公开(公告)日：2004-02-17
申请号：US08971341
申请日：1997-11-17
申请人： Karl J. Molnar , Gregory E. Bottomley , Sandeep Chennakeshu
发明人： Karl J. Molnar , Gregory E. Bottomley , Sandeep Chennakeshu
IPC分类号： H04B138
CPC分类号： H04W16/28 , H04B7/18532
摘要： A radio communication system includes a base station having a directional antenna for generating a plurality of beams. A first set of the beams is used to receive signals which are decoded at the base station. A second set of the beams is used for interrogating a cell to identify beams which should be added to the first set of beams (for example, in response to mobile terminals entering the cell). In one embodiment, the second set of beams comprises a plurality of searcher beams produced by a fixed-beam phased array antenna. In a second embodiment, the second set of beams comprises a single searcher beam which is scanned through the cell by an adaptive phased array antenna. The radio communication system can be used to communicate with indoor mobile terminals through a plurality of radio heads, and also can be used to communicate with orbiting satellites.
摘要翻译：无线电通信系统包括具有用于产生多个波束的定向天线的基站。第一组光束用于接收在基站处解码的信号。第二组波束用于询问小区以识别应该被添加到第一组波束（例如，响应于进入小区的移动终端）的波束。在一个实施例中，第二组波束包括由固定波束相控阵天线产生的多个搜索器波束。在第二实施例中，第二组波束包括通过自适应相控阵列天线扫描小区的单个搜索器波束。无线电通信系统可以用于通过多个无线电头与室内移动终端通信，并且还可以用于与轨道卫星通信。

9. 发明授权

US5577068A Generalized direct update viterbi equalizer 失效
标题翻译：广义直接更新维特比均衡器
公开(公告)号：US5577068A
公开(公告)日：1996-11-19
申请号：US274727
申请日：1994-07-18
申请人： Gregory E. Bottomley , Sandeep Chennakeshu , Paul W. Dent , R. David Koilpillai
发明人： Gregory E. Bottomley , Sandeep Chennakeshu , Paul W. Dent , R. David Koilpillai
IPC分类号： H04B7/005 , H03M13/23 , H04L25/03 , H04B1/10 , H04L27/01
CPC分类号： H04B7/005 , H04L25/03184 , H04L25/03292
摘要： A radio receiver for demodulating and equalizing digital information is disclosed. The receiver receives radio signals and processes the signals to produce data samples which are then stored. Reference values that model what the receiver should receive for various transmitted symbol sequence hypotheses are also stored. The receiver equalizes the received data using the stored reference values to produce symbol detection information, and updates the reference values based on the symbol detection information.
摘要翻译：公开了用于解调和均衡数字信息的无线电接收机。接收机接收无线电信号并处理信号以产生然后被存储的数据样本。对存储各种发送的符号序列假设的接收机应该接收什么的参考值也被存储。接收机使用所存储的参考值均衡接收到的数据以产生符号检测信息，并且基于符号检测信息来更新参考值。

10. 发明授权

US6085103A Compensating for fading in analog AM radio signals 失效
标题翻译：补偿模拟AM无线电信号中的衰落
公开(公告)号：US6085103A
公开(公告)日：2000-07-04
申请号：US802670
申请日：1997-02-19
申请人： Rajaram Ramesh , Sandeep Chennakeshu
发明人： Rajaram Ramesh , Sandeep Chennakeshu
IPC分类号： H04L9/30 , H04B7/005 , H04L9/36 , H04B15/00
CPC分类号： H04B7/005
摘要： A fading compensation apparatus and method are provided in which blocks of the analog AM signal (e.g., voice) are time-compressed at a transmitter. Gaps in the time-compressed signal are filled with pilot symbols (or similar complex waveforms) having known characteristics, such as predetermined amplitudes. The time-compressed analog AM signal (e.g., SSB or VSB) is transmitted over the fading channel. At an analog AM receiver, an estimate of the fading that occurred in the transmission channel is made by observing the amplitude of the received pilot symbols at discrete points in time, and interpolating to determine the amount of fading that occurred across the total transmitted signal. A fading compensator compares the received faded time-compressed signal with the interpolation results, and adjusts the amplitude and phase of the received signal accordingly to compensate for the fading that occurred in the transmission channel. The compensated analog AM signal is time expanded and output to a user.
摘要翻译：提供了一种衰落补偿装置和方法，其中模拟AM信号（例如，语音）的块在发射机处被时间压缩。用时间压缩信号的间隙填充具有已知特性（例如预定幅度）的导频符号（或类似的复杂波形）。时间压缩的模拟AM信号（例如，SSB或VSB）在衰落信道上传输。在模拟AM接收机处，通过在离散时间点观察接收到的导频符号的幅度来进行在传输信道中发生的衰落的估计，并进行内插以确定跨总传输信号发生的衰落量。衰落补偿器将接收到的衰落时间压缩信号与插值结果进行比较，并相应地调整接收信号的幅度和相位，以补偿在传输信道中发生的衰落。经补偿的模拟AM信号被时间扩展并输出给用户。

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