公开(公告)号：US10454664B2

公开(公告)日：2019-10-22

申请号：US15869042

申请日：2018-01-12

申请人： Xiao-an Wang

发明人： Xiao-an Wang

IPC分类号： H04L5/14 ,  H04W72/04 ,  H04W56/00 ,  H04L5/00 ,  H04B7/0452 ,  H04W88/08

摘要： Multipoint broadcasting relying on channel reciprocity in a TDD network requires that the broadcasters be calibrated. In the cases where the relative amplitude profiles and nonlinear phases are time-invariant or slow-varying, broadcaster calibration reduces to phase synchronization. Methods and apparatus are described that provide broadcaster calibration and phase synchronization with terminal feedback and overcome the drawbacks of self-calibration. The methods and apparatus are capable of calibrating hundreds of broadcaster antennas in massive antenna applications while maintaining an extremely low overhead. Applications of the described methods and apparatus include multipoint broadcasting in wireless networks, also known as coordinated multipoint transmission, or CoMP, in LTE-A (long-term evolution, advanced) networks, and distributed MIMO, massive MIMO, massive beamforming, etc., in other networks including 5G and 802.11. Applications also include frequency and phase synchronization of a cluster of wireless devices.

公开(公告)号：US20190222406A1

公开(公告)日：2019-07-18

申请号：US15869042

申请日：2018-01-12

申请人： Xiao-an Wang

发明人： Xiao-an Wang

IPC分类号： H04L5/14 ,  H04W72/04 ,  H04L5/00 ,  H04W56/00

摘要： Multipoint broadcasting relying on channel reciprocity in a TDD network requires that the broadcasters be calibrated. In the cases where the relative amplitude profiles and nonlinear phases are time-invariant or slow-varying, broadcaster calibration reduces to phase synchronization. Methods and apparatus are described that provide broadcaster calibration and phase synchronization with terminal feedback and overcome the drawbacks of self-calibration. The methods and apparatus are capable of calibrating hundreds of broadcaster antennas in massive antenna applications while maintaining an extremely low overhead. Applications of the described methods and apparatus include multipoint broadcasting in wireless networks, also known as coordinated multipoint transmission, or CoMP, in LTE-A (long-term evolution, advanced) networks, and distributed MIMO, massive MIMO, massive beamforming, etc., in other networks including 5G and 802.11. Applications also include frequency and phase synchronization of a cluster of wireless devices.

公开(公告)号：US09137077B2

公开(公告)日：2015-09-15

申请号：US13293813

申请日：2011-11-10

申请人： Xiao-an Wang

发明人： Xiao-an Wang

IPC分类号： H04B1/00 ,  H04L27/26 ,  H04L25/02 ,  H04L5/00 ,  H04L25/03

CPC分类号： H04L27/2613 ,  H04L5/0016 ,  H04L5/0023 ,  H04L5/0035 ,  H04L5/0048 ,  H04L25/0204 ,  H04L25/0224 ,  H04L2025/03426

摘要： Large-dimension MIMO and multipoint broadcasting in new generation of wireless networks create high demand for various types of pilots in transmission signals for channel estimation, data demodulation, synchronization, etc. More pilots, as in existing networks, use more resources and thus diminish the network capacity. Methods and apparatus of heterogeneous pilots are disclosed. A heterogeneous pilot has its own signal characteristics that are different from the primary information-bearing signals in the network. Heterogeneous pilots can be spread-spectrum signals in an OFDM-based wireless network. Heterogeneous pilots use no network resources, and can be as many as desired, and can be designed to have versatile utilities. Also described are methods and apparatus of heterogeneous pilot cancellation that minimizes the interference of heterogeneous pilots on the primary information-bearing signals. Applications of the described methods and apparatus include OFDM-based wireless cellular networks, such as LTE-advanced and Wireless LAN.

摘要翻译： 新一代无线网络中的大尺寸MIMO和多点广播对于信道估计，数据解调，同步等传输信号中的各种类型的导频产生了高需求。如现有网络中更多的飞行员使用更多的资源，从而减少 网络容量。 披露了异质飞行员的方法和装置。 异构导频具有与网络中的主要信息承载信号不同的信号特征。 异构导频可以是基于OFDM的无线网络中的扩频信号。 异构飞行员不使用网络资源，并且可以根据需要而设计，并且可以被设计为具有通用的实用程序。 还描述了使异构导频对主要信息承载信号的干扰最小化的异构导频消除的方法和装置。 所描述的方法和装置的应用包括基于OFDM的无线蜂窝网络，诸如LTE高级和无线LAN。

公开(公告)号：US09125074B2

公开(公告)日：2015-09-01

申请号：US13854130

申请日：2013-03-31

申请人： Xiao-an Wang

发明人： Xiao-an Wang

IPC分类号： H04W24/02 ,  H04B7/04 ,  H04W16/28 ,  H04B7/02

CPC分类号： H04W24/02 ,  H04B7/024 ,  H04B7/0452 ,  H04W16/28

摘要： MU-MIMO and CoMP have potentials to increase the cell capacity by many folds. Interferences and channel feedback overhead, however, severely limits such potentials. Method of reference signal-based grid of beams (RS-GOB) is described. RS-GOB distributes the effective antennas of a base station into multiple beams, thereby significantly reducing the feedback overhead of CoMP and making effective use of CoMP to turn the interferences into cooperating useful signals. RS-GOB also reduces the need for small HetNet cells, which mitigates the interferences of small HetNet cells on macro cells.

摘要翻译： MU-MIMO和CoMP具有将细胞容量增加许多倍的潜力。 然而，干扰和渠道反馈开销严重限制了这种潜力。 描述了基于信号的光束网格（RS-GOB）的方法。 RS-GOB将基站的有效天线分配到多个波束中，从而大大减少了CoMP的反馈开销，并有效利用了CoMP将干扰转化为合作的有用信号。 RS-GOB还减少了对小型HetNet电池的需求，从而减轻了小型HetNet电池在宏电池上的干扰。

公开(公告)号：US08705647B2

公开(公告)日：2014-04-22

申请号：US13087943

申请日：2011-04-15

申请人： Xiao-an Wang

发明人： Xiao-an Wang

IPC分类号： H04B7/02

CPC分类号： H04L25/0328 ,  H04L25/03292 ,  H04L25/03331 ,  H04L25/03891

摘要： A method is described that enables maximum-likelihood (ML) demodulation for MIMO communications over frequency-selective channels. An equalizer is typically employed to suppress inter-symbol interference (ISI) due to frequency-selectiveness of the channel, but the noise of the equalizer output can be highly correlated such that standard ML-MIMO demodulations cannot directly apply. The method comprises first constructing equivalent post-equalization MIMO channel and noise covariance matrix, and then de-correlating the equalizer output so that ML or near-ML MIMO demodulations can be applied to improve the performance. Additionally, successive ISI cancellation (SIC) is described for further performance improvement.

摘要翻译： 描述了一种能够通过频率选择信道进行MIMO通信的最大似然（ML）解调的方法。 通常采用均衡器来抑制由于信道的频率选择性引起的符号间干扰（ISI），但是均衡器输出的噪声可以高度相关，使得标准ML-MIMO解调不能直接应用。 该方法包括首先构建等效的后均衡MIMO信道和噪声协方差矩阵，然后将均衡器输出去相关，使ML或近ML MIMO解调可以应用于提高性能。 另外，为了进一步提高性能，描述了连续的ISI取消（SIC）。

公开(公告)号：US20140233684A1

公开(公告)日：2014-08-21

申请号：US13769250

申请日：2013-02-15

申请人： Xiao-an Wang

发明人： Xiao-an Wang

IPC分类号： H04L25/02

CPC分类号： H04L25/0204

摘要： Most wireless channels are sparse, so sparse channel-based methods can be used for channel estimation and feedback with much better estimation accuracy and much lower feedback overhead. However, certain wireless channels can be non-sparse, for which sparse channel-based methods may cause degraded estimation quality and increased feedback overhead. Means of detecting the channel sparseness are described that provide simple and effective channel sparseness indicators and safeguard against the mismatch between non-sparse channels and sparse channel-based methods. Various fallback options can be used under non-sparse channels such that estimation degradation and feedback overhead are both minimized. Fake multipath removal in continuous time-domain parameter extraction, a sparse channel-based method, is also described that further improves estimation quality and reduces feedback overhead.

摘要翻译： 大多数无线信道是稀疏的，因此基于信道的稀疏方法可以用于信道估计和反馈，具有更好的估计精度和更低的反馈开销。 然而，某些无线信道可以是非稀疏的，对于这些信道，基于信道的稀疏方法可能导致估计质量下降和增加的反馈开销。 描述了检测通道稀疏度的手段，其提供简单有效的信道稀疏指示符，并且防止非稀疏信道与基于信道的稀疏信道之间的不匹配。 可以在非稀疏信道下使用各种备用选项，从而将估计降级和反馈开销都最小化。 还描述了连续时域参数提取中的虚拟多径去除，这是一种基于稀疏信道的方法，可进一步提高估计质量并降低反馈开销。

公开(公告)号：US20130242841A1

公开(公告)日：2013-09-19

申请号：US13419592

申请日：2012-03-14

申请人： Xiao-an Wang

发明人： Xiao-an Wang

IPC分类号： H04W72/00

CPC分类号： H04W72/005 ,  H04L5/00 ,  H04L5/0023 ,  H04L5/0035 ,  H04L5/0048 ,  H04L25/022 ,  H04L25/0224

摘要： Methods and apparatus of channel feedback are disclosed. In OFDM systems, the channel is acquired in the frequency domain. A generic multipath model for wireless channels, however, reveals that the time-domain parameters of the channel require much smaller data than the frequency-domain representation of the channel. Means to extracting the time-domain parameters from the frequency-domain channel samples are described for both the continuous time domain and the discrete time domain. Refinements of the time-domain parameters via minimizing a frequency-domain matching error are also described, which further improve the quality of the channel feedback and reduce the feedback overhead. Channel feedback with the time-domain parameters requires only a small fraction of the feedback overhead that is needed by existing channel feedback schemes, and maintains consistently superior performances over wireless channels of various delay spreads, short or long.

摘要翻译： 公开了信道反馈的方法和装置。 在OFDM系统中，在频域中获取信道。 然而，用于无线信道的通用多径模型揭示了信道的时域参数需要比信道的频域表示少得多的数据。 对于连续时域和离散时域都描述了从频域信道样本中提取时域参数的手段。 还描述了通过最小化频域匹配误差来改进时域参数，这进一步提高了信道反馈的质量并减少了反馈开销。 具有时域参数的信道反馈仅需要现有信道反馈方案所需的反馈开销的一小部分，并且在短时间或长的各种延迟传播的无线信道上保持一致的优异性能。

公开(公告)号：US20130083778A1

公开(公告)日：2013-04-04

申请号：US13249238

申请日：2011-09-30

申请人： Xiao-an Wang

发明人： Xiao-an Wang

IPC分类号： H04W40/00 ,  H04W92/00 ,  H04L27/28 ,  H04B7/216

CPC分类号： H04L1/0027 ,  H04L1/0026 ,  H04L1/04 ,  H04L25/0228 ,  H04L2001/0093

摘要： Multipoint broadcasting requires that the downlink-channel information be available at collaborating base stations. Methods and apparatus for wideband analog channel feedback are described that provide downlink-channel information feedback from mobile users to base stations via uplink channels, and that use very few or no resources of the RAT of the wireless cellular network. Also described are methods and apparatus that perform channel-feedback signal cancellation at base stations to reduce its interference on the uplink-traffic signal. Wideband analog channel feedback is adaptable to the feedback bandwidth in uplink, and it offers frequency diversity to combat the deep fading in feedback channels. Wideband analog channel feedback is also applicable to uplink channel-information feedback. Applications of the described methods and apparatus include multipoint broadcasting in a wireless cellular network, and more generally, channel feedback between two communicating devices in a communications network.

摘要翻译： 多点广播需要下行链路信道在协作基站可用。 描述了用于宽带模拟信道反馈的方法和装置，其通过上行链路信道从移动用户向基站提供下行链路信道信息反馈，并且使用无线蜂窝网络的RAT的很少或没有资源。 还描述了在基站执行信道反馈信号消除以减少其对上行链路业务信号的干扰的方法和装置。 宽带模拟信道反馈适用于上行链路的反馈带宽，并提供频率分集以抵御反馈信道的深度衰落。 宽带模拟信道反馈也适用于上行链路信道信息反馈。 所描述的方法和装置的应用包括无线蜂窝网络中的多点广播，更一般地，在通信网络中的两个通信设备之间的信道反馈。

公开(公告)号：US20120320765A1

公开(公告)日：2012-12-20

申请号：US13163725

申请日：2011-06-20

申请人： Xiao-an Wang

发明人： Xiao-an Wang

IPC分类号： H04W24/00

CPC分类号： H04L25/0228 ,  H04L25/022 ,  H04L25/0222 ,  H04L25/0232 ,  H04W56/0035

摘要： Methods and apparatus are described that provide efficient detection of the carrier-phase difference (CPD) between communicating devices over the entire signal bandwidth. The CPD detection utilizes the linear structure of the CPD, which eliminates most of the feedback overhead. Both feedback mechanisms, compact digitized feedback, and feedback via fast signaling protocols, are described. The CPD can be decomposed into a fixed/slow-changing portion and a fast-varying portion, with the former being pre-calibrated and communicated prior to communications sessions, thus further reducing the feedback overhead and improving the CPD detection accuracy. The nonlinearity in the TX/RX chains can also be pre-calibrated, allowing CPDs with more general structures to be detected by methods that detect CPDs with linear structures. Applications of the described methods and apparatus include wireless multipoint broadcast systems, also known as coordinated multipoint transmission, or CoMP, in LTE-A (long-term evolution, advanced) systems, and frequency and phase synchronization of a cluster of base stations.

摘要翻译： 描述了在整个信号带宽上提供通信设备之间的载波相位差（CPD）的有效检测的方法和装置。 CPD检测利用CPD的线性结构，消除了大部分的反馈开销。 描述了反馈机制，紧凑型数字化反馈和通过快速信令协议的反馈。 CPD可以分解为固定/慢变化部分和快速变化部分，前者在通信会话之前被预校准和通信，从而进一步减少反馈开销并提高CPD检测精度。 TX / RX链中的非线性也可以被预校准，允许通过用线性结构检测CPD的方法来检测具有更一般结构的CPD。 所描述的方法和装置的应用包括LTE-A（长期演进，高级）系统中的无线多点广播系统，也称为协调多点传输，或CoMP，以及基站簇的频率和相位同步。

公开(公告)号：US20120278690A1

公开(公告)日：2012-11-01

申请号：US13546180

申请日：2012-07-11

申请人： Xiao-an Wang ,  Jens Berkmann

发明人： Xiao-an Wang ,  Jens Berkmann

IPC分类号： H03M13/09 ,  G06F11/10

CPC分类号： H03M13/091

摘要： A description is given of an apparatus that includes a division unit configured to receive a data stream and to divide the received data stream into a plurality of data segments. The apparatus further includes a plurality of first CRC check units, wherein each of the first CRC check units is configured to perform a first CRC check of a respective one of the plurality of data segments, the plurality of first CRC checks being performed concurrently, and wherein each of the first CRC check units is configured to perform a second CRC check based on an output of the respective first CRC check unit.

摘要翻译： 给出了一种包括被配置为接收数据流并将接收的数据流划分成多个数据段的分割单元的装置的描述。 该装置还包括多个第一CRC校验单元，其中第一CRC校验单元中的每一个被配置为执行多个数据段中的相应一个数据段的第一CRC校验，多个第一CRC校验同时执行，以及 其中，所述第一CRC校验单元中的每一个被配置为基于相应的第一CRC校验单元的输出执行第二CRC校验。