公开(公告)号：US08831155B2

公开(公告)日：2014-09-09

申请号：US13479210

申请日：2012-05-23

Applicant: Tevfik Yucek ,  Kai Shi ,  Susinder Rajan Gulasekaran ,  Richard Melvin Mosko, Jr.

Inventor： Tevfik Yucek ,  Kai Shi ,  Susinder Rajan Gulasekaran ,  Richard Melvin Mosko, Jr.

IPC: H04L27/08

CPC classification number: G01S7/021 ,  H04K3/226 ,  H04K3/822 ,  H04K2203/18 ,  H04L27/2633

Abstract: A method of identifying radar in a wireless device includes detecting an event corresponding to receipt of a signal by the wireless device. The event can include an analog to digital converter (ADC) saturation, a radio frequency (RF) saturation, and/or an ADC power high condition. Notably, the gain change in the wireless device is delayed for a first predetermined time period. Data preceding the event for the first predetermined time period can be buffered. A first low-resolution fast Fourier transform (FFT), wherein low-resolution FFTs are referred to as short FFTs, can be performed with the buffered data. The first short FFT can be processed. When results of the processing indicate the signal is radar, the radar can then be identified.

Abstract translation: 一种在无线设备中识别雷达的方法包括：检测与无线设备接收的信号相对应的事件。 该事件可以包括模数转换器（ADC）饱和，射频（RF）饱和和/或ADC功率高电平状态。 值得注意的是，无线设备中的增益改变延迟了第一预定时间段。 可以缓冲在第一预定时间段之前的事件之前的数据。 可以使用缓冲的数据来执行第一低分辨率快速傅里叶变换（FFT），其中低分辨率FFT被称为短FFT。 可以处理第一个短FFT。 当处理结果表明信号是雷达时，可以识别雷达。

公开(公告)号：US08286049B1

公开(公告)日：2012-10-09

申请号：US12607772

申请日：2009-10-28

Applicant: William J. McFarland ,  Kai Shi ,  Bruce Busby

Inventor： William J. McFarland ,  Kai Shi ,  Bruce Busby

IPC: H03M13/00

CPC classification number: H03M13/6527 ,  H03M7/3084 ,  H03M13/1148 ,  H03M13/23 ,  H03M13/6362 ,  H03M13/6516 ,  H03M13/6519

Abstract: A configurable transmitter for a wireless communication system may include a flexible block coder, an IFFT block, an analog and RF block, and an antenna coupled in series. The flexible block coder may advantageously perform forward error correction and mapping of a data stream to generate a processed data vector. To perform these functions, the flexible block coder may include a data formatter and a multiplier. The data formatter may format the data stream into an output vector, whereas the multiplier may multiply the output vector by a configurable channel coding matrix to generate the processed data vector. The size of the output vector may be a reflection legacy compatibility and data rate. The size of the processed data vector is equal to a product of the output vector and an inverse of a coding rate. The channel coding matrix may be compressed.

Abstract translation: 用于无线通信系统的可配置发射机可以包括灵活块编码器，IFFT块，模拟和RF块以及串联耦合的天线。 灵活块编码器可以有利地执行数据流的前向纠错和映射以产生经处理的数据向量。 为了执行这些功能，灵活块编码器可以包括数据格式化器和乘法器。 数据格式化器可以将数据流格式化为输出向量，而乘法器可以将输出向量乘以可配置的信道编码矩阵以生成经处理的数据向量。 输出向量的大小可以是反射传统兼容性和数据速率。 处理数据向量的大小等于输出向量与编码率的倒数的乘积。 可以压缩信道编码矩阵。

公开(公告)号：US20120189085A1

公开(公告)日：2012-07-26

申请号：US13434829

申请日：2012-03-29

Applicant: Kai Shi

Inventor： Kai Shi

IPC: H04L25/08

CPC classification number: H04L27/261 ,  H04L5/0023 ,  H04L5/0048 ,  H04L27/2656 ,  H04L27/2657 ,  H04L27/2662 ,  H04L27/2672 ,  H04L27/2679

Abstract: Receivers typically detect the presence of a pilot tone, transmitted as part of an RF signal, and use the pilot tone as a reference to detect symbols in the received RF signal. However, improper synchronization between the transmitter and the receiver units can result in timing offset and carrier frequency offset in the digitized received RF signal, impair the orthogonality between OFDM sub-carriers, and cause inter-carrier interference. Phase offsets caused by carrier frequency offset and timing offset can also degrade receiver performance. Functionality can be incorporated to estimate the phase offset over multiple symbols. Estimating the phase offset over multiple symbols in the received RF signal can lower the error rate. Correcting the phase offset in the received RF signal can ensure accurate sampling of the received signal, accurate channel estimates, and accurate decoding of the digitized received signal. This can minimize receiver performance degradation.

Abstract translation: 接收机通常检测作为RF信号的一部分发送的导频音的存在，并且使用导频音作为参考来检测所接收的RF信号中的符号。 然而，发射机和接收机单元之间的不正确的同步可能导致数字化接收的RF信号中的定时偏移和载波频率偏移，损害OFDM子载波之间的正交性，并引起载波间干扰。 由载波频率偏移和定时偏移引起的相位偏移也可能降低接收机性能。 可以并入功能以估计多个符号的相位偏移。 估计接收的RF信号中多个符号的相位偏移可以降低误码率。 校正接收的RF信号中的相位偏移可以确保接收信号的准确采样，准确的信道估计和数字化接收信号的精确解码。 这可以最大限度地减少接收机性能下降。

公开(公告)号：US08121220B1

公开(公告)日：2012-02-21

申请号：US12135054

申请日：2008-06-06

Applicant: Kai Shi ,  Ning Zhang ,  Tao-Fei Samuel Ng

Inventor： Kai Shi ,  Ning Zhang ,  Tao-Fei Samuel Ng

IPC: H03K9/00 ,  H04L27/00

CPC classification number: H04L25/03197 ,  H04B7/0413 ,  H04L1/06 ,  H04L25/0246 ,  H04L25/03292 ,  H04L25/03318 ,  H04L2025/03426

Abstract: In a multiple-input multiple-output communication system, a transmit symbol vector and a set of soft decision metrics may be estimated using a reduced complexity maximum likelihood (ML) detection method based on a receive symbol vector and a QR decomposition of a set of permuted channel matrices. The reduced complexity ML detection method may use a different permuted channel matrix to estimate each transmit symbol in a transmit symbol vector. A set of error distances may be calculated for the estimated transmit symbol vector, each error distance calculated choosing a different value from a signal constellation subset for a transmit symbol in the estimated transmit symbol vector. A soft decision metric may be calculated using the elements from the set of error distances. In some embodiments the transmit symbols of a transmit symbol vector and the soft decision metrics for each transmit symbol may be determined in parallel.

Abstract translation: 在多输入多输出通信系统中，可以使用基于接收符号矢量的降低的复杂度最大似然（ML）检测方法来估计发送符号向量和一组软判决度量， 置换通道矩阵。 降低复杂度ML检测方法可以使用不同的置换信道矩阵来估计发射符号向量中的每个发射符号。 可以针对估计的发射符号向量计算一组误差距离，每个误差距离被选择与估计的发射符号向量中的发射符号的信号星座子集不同的值。 可以使用来自误差距离集合的元素来计算软判决度量。 在一些实施例中，可以并行确定发射符号向量的发射符号和每个发射符号的软判决度量。

公开(公告)号：US09253742B1

公开(公告)日：2016-02-02

申请号：US11947749

申请日：2007-11-29

Applicant: Qinfang Sun ,  Kai Shi

Inventor： Qinfang Sun ,  Kai Shi

IPC: H04J3/06 ,  H04W56/00 ,  H04L7/04

CPC classification number: H04W56/00 ,  H04L7/042

Abstract: Improved methods of decoding data symbols of a high throughput (HT) data field in a mixed mode packet are provided. In one embodiment, first and second data symbols of the HT data field can be decoded using timing information derived from a legacy header of the mixed mode packet. In another embodiment, the first data symbol of the HT data field can be decoded using timing information derived from a legacy header of the mixed mode packet, whereas the second data symbol of the HT data field can be decoded using approximately half of the tones of the HT long training field in the mixed mode packet. Subsequent data symbols of the HT data field can be decoded using all tones of the HT long training field in the received mixed mode packet.

Abstract translation: 提供了对混合模式分组中的高吞吐量（HT）数据字段的数据符号进行解码的改进方法。 在一个实施例中，可以使用从混合模式分组的传统头部导出的定时信息来解码HT数据字段的第一和第二数据符号。 在另一个实施例中，可以使用从混合模式分组的传统头部导出的定时信息来解码HT数据字段的第一数据符号，而HT数据字段的第二数据符号可以使用大约一半的 HT长训练场在混合模式包中。 可以使用接收到的混合模式分组中的HT长训练字段的所有音调来解码HT数据字段的后续数据符号。

公开(公告)号：US08457261B1

公开(公告)日：2013-06-04

申请号：US12706932

申请日：2010-02-17

Applicant: Kai Shi ,  Ning Zhang

Inventor： Kai Shi ,  Ning Zhang

IPC: H04L27/08

CPC classification number: H04L27/0002 ,  H03G3/3078

Abstract: Functionality can be implemented for automatic gain control (AGC) in a wireless network device to determine whether to change the gain of the wireless network device based on determining the strength of an RF signal. At various time instants, the strength of the RF signal can be compared against different thresholds to determine the presence of and severity of the saturation of the RF front end. The gain settings can be adjusted based on comparing the strength of the RF signal with a set of thresholds. This can help the wireless network device receive RF signals with little or no distortion, and can minimize RF saturation, gain compression, false detection and other performance degradation at the wireless network device.

公开(公告)号：US20130121173A1

公开(公告)日：2013-05-16

申请号：US13297202

申请日：2011-11-15

Applicant: Qifan CHEN ,  Kai SHI ,  Ning ZHANG

Inventor： Qifan CHEN ,  Kai SHI ,  Ning ZHANG

IPC: H04W24/00

CPC classification number: H04W24/08 ,  G01S7/40 ,  G01S13/765 ,  H04J3/0667

Abstract: A method and apparatus for improving the accuracy of a round trip time (RTT) estimate between a first device and a second device are disclosed. The method involves calculating an acknowledgement correction factor and a unicast correction factor. These correction factors are used to compensate for symbol boundary time errors resulting from multipath effects.

Abstract translation: 公开了一种用于提高第一设备和第二设备之间的往返时间（RTT）估计精度的方法和设备。 该方法涉及计算确认校正因子和单播校正因子。 这些校正因子用于补偿由多径效应引起的符号边界时间误差。

公开(公告)号：US08144683B1

公开(公告)日：2012-03-27

申请号：US11947746

申请日：2007-11-29

Applicant: Qinfang Sun ,  Kai Shi

Inventor： Qinfang Sun ,  Kai Shi

IPC: H04J3/24

CPC classification number: H04L27/2602 ,  H04L25/0202 ,  H04L27/2663 ,  H04L27/2665 ,  H04L27/2675 ,  H04L27/2695

Abstract: After detecting the predetermined phase rotation, a receiver can advantageously remove any cyclic shifting delays (CSDs) from the mixed mode packet for each chain. Once any CSDs are removed, the receiver can perform timing offset estimation and decode the mixed mode packet. In another embodiment, a timing offset from a channel for a first chain without any CSDs can be estimated. Compensation for the timing offset in the first chain can then be performed. At this point, the CSDs from other chains can then be removed. After CSD removal, compensation for any timing offsets in the other chains can be performed using the timing offset in the first chain.

Abstract translation: 在检测到预定的相位旋转之后，接收机可以有利地从每个链路的混合模式分组中去除任何循环移位延迟（CSD）。 一旦任何CSD被去除，接收机可以执行定时偏移估计和解码混合模式分组。 在另一个实施例中，可以估计来自没有任何CSD的第一链的信道的定时偏移。 然后可以执行第一链中的定时偏移的补偿。 在这一点上，可以将其他链的CSD移除。 在CSD去除之后，可以使用第一链中的定时偏移来执行其他链中的任何定时偏移的补偿。

公开(公告)号：US09247541B2

公开(公告)日：2016-01-26

申请号：US13233861

申请日：2011-09-15

Applicant: Youhan Kim ,  James Cho ,  Kai Shi ,  Ning Zhang

Inventor： Youhan Kim ,  James Cho ,  Kai Shi ,  Ning Zhang

IPC: H04B7/00 ,  H04W72/04 ,  H04L1/06 ,  H04L5/00

CPC classification number: H04W72/0453 ,  H04L1/0643 ,  H04L5/0023 ,  H04L5/0044 ,  H04L5/0053

Abstract: A first combination of frequency bands is selected for transmitting a first data packet, and a second, different combination of frequency bands is selected for transmitting a second data packet. A data stream is divided into a first set of data and a second set of data. The first set of data is allocated to the first combination of frequency bands, and the second set of data is allocated to the second combination of frequency bands.

Abstract translation: 选择频带的第一组合用于发送第一数据分组，并且选择频带的第二不同组合来发送第二数据分组。 数据流被分成第一组数据和第二组数据。 第一组数据被分配给频带的第一组合，并且第二组数据被分配给频带的第二组合。

公开(公告)号：US08787191B2

公开(公告)日：2014-07-22

申请号：US13297202

申请日：2011-11-15

Applicant: Qifan Chen ,  Kai Shi ,  Ning Zhang

Inventor： Qifan Chen ,  Kai Shi ,  Ning Zhang

IPC: H04L12/26 ,  G01S7/40 ,  G01S13/76 ,  H04J3/06

CPC classification number: H04W24/08 ,  G01S7/40 ,  G01S13/765 ,  H04J3/0667

Abstract: A method and apparatus for improving the accuracy of a round trip time (RTT) estimate between a first device and a second device are disclosed. The method involves calculating an acknowledgement correction factor and a unicast correction factor. These correction factors are used to compensate for symbol boundary time errors resulting from multipath effects.

Abstract translation: 公开了一种用于提高第一设备和第二设备之间的往返时间（RTT）估计精度的方法和设备。 该方法涉及计算确认校正因子和单播校正因子。 这些校正因子用于补偿由多径效应引起的符号边界时间误差。