公开(公告)号：US20070183370A1

公开(公告)日：2007-08-09

申请号：US11609493

申请日：2006-12-12

申请人： Mark Wallace ,  Jay Walton

发明人： Mark Wallace ,  Jay Walton

IPC分类号： H04Q7/00

CPC分类号： H04L27/0014 ,  H04L27/2613 ,  H04L27/2656 ,  H04L27/2657 ,  H04L27/2675 ,  H04L27/2676 ,  H04W74/02 ,  H04W84/12 ,  H04W88/04

摘要： Techniques for extending transmission range in a WLAN are described. In an aspect, a receiving station determines the frequency error between a transmitting station and the receiving station based on one or more initial packet transmissions and corrects this frequency error for subsequent packet transmissions received from the transmitting station. The residual frequency error is small after correcting for the frequency error and allows the receiving station to perform coherent accumulation/integration over a longer time interval to detect for a packet transmission. The longer coherent accumulation interval improves detection performance, especially at low SNRs for extended transmission range. The techniques may be used whenever the receiving station knows the identity of the transmitting station, e.g., if the subsequent packet transmissions are scheduled. In another aspect, a preamble is generated with a longer spreading sequence and sent with each packet transmission.

摘要翻译： 描述了在WLAN中扩展传输范围的技术。 在一方面，接收站基于一个或多个初始分组传输来确定发射站和接收站之间的频率误差，并且校正该频率误差以用于从发射站接收的后续分组传输。 在校正频率误差之后，剩余频率误差较小，并且允许接收站在更长的时间间隔上执行相干累积/积分以检测分组传输。 较长的相干累加间隔提高了检测性能，特别是在扩展传输范围的低SNR时。 每当接收站知道发射台的身份时，例如如果后续分组传输被调度，则可以使用这些技术。 在另一方面，产生具有较长扩展序列的前同步码并且随每个分组传输一起发送。

公开(公告)号：US20060285531A1

公开(公告)日：2006-12-21

申请号：US11158586

申请日：2005-06-21

申请人： Steven Howard ,  John Ketchum ,  Mark Wallace ,  Peter Monsen ,  Jay Walton

发明人： Steven Howard ,  John Ketchum ,  Mark Wallace ,  Peter Monsen ,  Jay Walton

IPC分类号： H04J1/00 ,  H04L1/02

CPC分类号： H04B7/0854 ,  H04B7/0413 ,  H04L25/0246 ,  H04L25/0248 ,  H04L2025/03426 ,  H04L2025/03605 ,  H04L2025/03611

摘要： Techniques to efficiently derive a spatial filter matrix are described. In a first scheme, a Hermitian matrix is iteratively derived based on a channel response matrix, and a matrix inversion is indirectly calculated by deriving the Hermitian matrix iteratively. The spatial filter matrix is derived based on the Hermitian matrix and the channel response matrix. In a second scheme, multiple rotations are performed to iteratively obtain first and second matrices for a pseudo-inverse matrix of the channel response matrix. The spatial filter matrix is derived based on the first and second matrices. In a third scheme, a matrix is formed based on the channel response matrix and decomposed to obtain a unitary matrix and a diagonal matrix. The spatial filter matrix is derived based on the unitary matrix, the diagonal matrix, and the channel response matrix.

摘要翻译： 描述了有效地导出空间滤波器矩阵的技术。 在第一种方案中，基于信道响应矩阵迭代地导出Hermitian矩阵，并且通过迭代地导出Hermitian矩阵来间接计算矩阵求逆。 基于Hermitian矩阵和信道响应矩阵导出空间滤波矩阵。 在第二方案中，执行多次旋转以迭代地获得用于信道响应矩阵的伪逆矩阵的第一和第二矩阵。 基于第一和第二矩阵导出空间滤波器矩阵。 在第三方案中，基于信道响应矩阵形成矩阵并分解以获得酉矩阵和对角矩阵。 基于单一矩阵，对角矩阵和信道响应矩阵导出空间滤波器矩阵。

公开(公告)号：US20060262750A1

公开(公告)日：2006-11-23

申请号：US11417946

申请日：2006-05-03

申请人： Jay Walton ,  Mark Wallace ,  Jack Holtzman ,  Franklin Antonio

发明人： Jay Walton ,  Mark Wallace ,  Jack Holtzman ,  Franklin Antonio

IPC分类号： H04Q7/00

CPC分类号： H04W52/343 ,  H04W16/04 ,  H04W72/06

摘要： Techniques to partition and allocate the available system resources among cells in a communication system, and to allocate the resources in each cell to terminals for data transmission on the uplink. In one aspect, adaptive reuse schemes are provided wherein the available system resources may be dynamically and/or adaptively partitioned and allocated to the cells based on a number of factors such as the observed interference levels, loading conditions, system requirements, and so on. A reuse plan is initially defined and may be redefined to reflect changes in the system. In another aspect, the system resources may be partitioned such that each cell is allocated a set of channels having different performance levels. In yet another aspect, terminals in each cell are scheduled for data transmission (e.g., based on their priority or load requirements) and assigned channels based on their tolerance to interference and the channels' performance.

公开(公告)号：US20060105761A1

公开(公告)日：2006-05-18

申请号：US11301790

申请日：2005-12-12

申请人： Jay Walton ,  Mark Wallace ,  Steven Howard

发明人： Jay Walton ,  Mark Wallace ,  Steven Howard

IPC分类号： H04Q7/20

CPC分类号： H04W72/121 ,  H04B7/0417 ,  H04B7/0626 ,  H04B7/0697 ,  H04B7/0891 ,  H04W72/1205

摘要： Techniques to schedule uplink data transmission for a number of terminals in a wireless communication system. In one method, a number of sets of terminals are formed for possible data transmission, with each set including a unique combination of terminals and corresponds to a hypothesis to be evaluated. The performance of each hypothesis is evaluated (e.g., based on channel response estimates for each terminal) and one of the evaluated hypotheses is selected based on the performance. The terminals in the selected hypothesis are scheduled for data transmission. A successive cancellation receiver processing scheme may be used to process the signals transmitted by the scheduled terminals. In this case, one or more orderings of the terminals in each set may be formed, with each terminal ordering corresponding to a sub-hypothesis to be evaluated. The performance of each sub-hypothesis is then evaluated and one of the sub-hypotheses is selected.

公开(公告)号：US20060104381A1

公开(公告)日：2006-05-18

申请号：US11184601

申请日：2005-07-18

申请人： Murali Menon ,  John Ketchum ,  Mark Wallace ,  Jay Walton ,  Steven Howard

发明人： Murali Menon ,  John Ketchum ,  Mark Wallace ,  Jay Walton ,  Steven Howard

IPC分类号： H04B7/02 ,  H04K1/10

CPC分类号： H04B7/0417 ,  H01Q3/26 ,  H04B7/043 ,  H04B7/0617 ,  H04B7/0634 ,  H04L5/0025 ,  H04L5/0044 ,  H04L5/0053 ,  H04L5/006 ,  H04L5/0085 ,  H04L5/0096 ,  H04L25/0204 ,  H04L25/0246 ,  H04L25/0248 ,  H04L25/03343 ,  H04L2025/03414 ,  H04L2025/03426 ,  H04L2025/03802 ,  H04W52/42

摘要： Techniques to perform beam-steering and beam-forming to transmit data on a single eigenmode in a wideband multiple-input channel. In one method, a steering vector is obtained for each of a number of subbands. Depending on how the steering vectors are defined, beam-steering or beam-forming can be achieved for each subband. The total transmit power is allocated to the subbands based on a particular power allocation scheme (e.g., full channel inversion, selective channel inversion, water-filling, or uniform). A scaling value is then obtained for each subband based on its allocated transmit power. Data to be transmitted is coded and modulated to provide modulation symbols. The modulation symbols to be transmitted on each subband are scaled with the subband's scaling value and further preconditioned with the subband's steering vector. A stream of preconditioned symbols is then formed for each transmit antenna.

摘要翻译： 执行波束转向和波束成形以在宽带多输入通道中的单个本征模上传输数据的技术。 在一种方法中，为多个子带中的每一个获得导向矢量。 取决于如何定义导向矢量，可以为每个子带实现波束转向或波束形成。 基于特定功率分配方案（例如，全信道反转，选择性信道反转，充水或均匀）将总发射功率分配给子带。 然后根据其分配的发射功率，为每个子带获得缩放值。 要发送的数据被编码和调制以提供调制符号。 要在每个子带上发送的调制符号用子带的缩放值进行缩放，并进一步用子带的导向矢量进行预处理。 然后为每个发射天线形成预处理符号流。

公开(公告)号：US20060093067A1

公开(公告)日：2006-05-04

申请号：US11298639

申请日：2005-12-08

申请人： Ahmad Jalali ,  Jay Walton ,  Mark Wallace

发明人： Ahmad Jalali ,  Jay Walton ,  Mark Wallace

IPC分类号： H04B7/06 ,  H04K1/10

CPC分类号： H04L5/023

摘要： Transmitter and receiver units for use in an OFDM communications system and configurable to support multiple types of services. The transmitter unit includes one or more encoders, a symbol mapping element, and a modulator. Each encoder receives and codes a respective channel data stream to generate a corresponding coded data stream. The symbol mapping element receives and maps data from the coded data streams to generate modulation symbol vectors, with each modulation symbol vector including a set of data values used to modulate a set of tones to generate an OFDM symbol. The modulator modulates the modulation symbol vectors to provide a modulated signal suitable for transmission. The data from each coded data stream is mapped to a respective set of one or more “circuits”. Each circuit can be defined to include a number of tones from a number of OFDM symbols, a number of tones from a single OFDM symbol, all tones from one or more OFDM symbols, or some other combination of tones. The circuits can have equal size or different sizes. Different circuits can be used for full rate data (e.g., active speech) and low rate data (e.g., silence periods).

公开(公告)号：US20060050770A1

公开(公告)日：2006-03-09

申请号：US11042126

申请日：2005-01-24

申请人： Mark Wallace ,  Irina Medvedev ,  Jay Walton

发明人： Mark Wallace ,  Irina Medvedev ,  Jay Walton

IPC分类号： H04L1/02 ,  H04B1/707

CPC分类号： H04L25/0242 ,  H04B7/0669 ,  H04B7/068 ,  H04B7/0854 ,  H04L1/0606 ,  H04L1/0618 ,  H04L5/0023 ,  H04L25/0204 ,  H04L25/0224 ,  H04L25/0256 ,  H04L27/2613 ,  H04L27/2626 ,  H04L27/2647 ,  H04L2025/03426

摘要： A receiving entity obtains received symbols for a data transmission having at least one data symbol stream sent with space-time transmit diversity (STTD). The receiving entity derives an overall channel response matrix in accordance with the STTD encoding scheme used for the data transmission, derives a spatial filter matrix based on the overall channel response matrix, and performs spatial matched filtering on a vector of received symbols for each 2-symbol interval to obtain a vector of detected symbols for the 2-symbol interval. The receiving entity may perform post-processing (e.g., conjugation) on the detected symbols if needed. Alternatively, the receiving entity derives a spatial filter matrix based on an effective channel response matrix, performs spatial matched filtering on the received symbols for each symbol period to obtain detected symbols for that symbol period, and combines multiple estimates obtained for each data symbol sent with STTD.

摘要翻译： 接收实体获得具有用空时传输分集（STTD）发送的至少一个数据符号流的数据传输的接收符号。 接收实体根据用于数据传输的STTD编码方案导出整体信道响应矩阵，基于整个信道响应矩阵导出空间滤波器矩阵，并且对每个2-信道的接收符号的向量执行空间匹配滤波， 符号间隔以获得用于2符号间隔的检测符号的向量。 如果需要，接收实体可以在检测到的符号上执行后处理（例如，共轭）。 或者，接收实体基于有效信道响应矩阵导出空间滤波器矩阵，对于每个符号周期对接收到的符号执行空间匹配滤波，以获得该符号周期的检测符号，并且将针对每个符号周期发送的每个数据符号获得的多个估计合并 STTD。

公开(公告)号：US20050238111A1

公开(公告)日：2005-10-27

申请号：US10821390

申请日：2004-04-09

申请人： Mark Wallace ,  Jay Walton ,  Steven Howard

发明人： Mark Wallace ,  Jay Walton ,  Steven Howard

IPC分类号： H04J99/00 ,  H04B7/06 ,  H04L25/03 ,  H04L27/26 ,  H04L1/02

CPC分类号： H04B7/0615 ,  H04B7/0417

摘要： Techniques for generating and using steering matrices for pseudo-random transmit steering (PRTS) are described. For PRTS, a transmitting entity performs spatial processing with steering matrices so that a data transmission observes an ensemble of “effective” channels formed by the actual channel used for data transmission and the steering matrices used for PRTS. The steering matrices may be generated by selecting a base matrix, which may be a Walsh matrix or a Fourier matrix. Different combinations of scalars are then selected, with each combination including at least one scalar for at least one row of the base matrix. Each scalar may be a real or complex value (e.g., +1, −1, +j, or −j, where j={square root}{square root over (−1)}). Different steering matrices are generated by multiplying the base matrix with each of the different combinations of scalars. The steering matrices are different permutations of the base matrix.

摘要翻译： 描述了用于产生和使用用于伪随机发射转向（PRTS）的导向矩阵的技术。 对于PRTS，发射实体使用导引矩阵执行空间处理，使得数据传输观察由用于数据传输的实际信道和用于PRTS的导引矩阵形成的“有效”信道的集合。 可以通过选择可以是沃尔什矩阵或傅立叶矩阵的基本矩阵来生成导引矩阵。 然后选择标量的不同组合，其中每个组合包括用于至少一行基本矩阵的至少一个标量。 每个标量可以是实数或复数值（例如，+1，-1，+ j或-j，其中j = {平方根} {平方根超过（-1）}）。 通过将基本矩阵与标量的不同组合中的每一个相乘来生成不同的导向矩阵。 导向矩阵是基本矩阵的不同排列。

公开(公告)号：US20050175115A1

公开(公告)日：2005-08-11

申请号：US11008865

申请日：2004-12-09

申请人： Jay Walton ,  Lizhong Zheng ,  John Ketchum ,  Mark Wallace ,  Steven Howard

发明人： Jay Walton ,  Lizhong Zheng ,  John Ketchum ,  Mark Wallace ,  Steven Howard

IPC分类号： H04J99/00 ,  H04L1/06 ,  H04L1/02

CPC分类号： H04B7/0417 ,  H04B7/0456 ,  H04B7/0669 ,  H04B17/336 ,  H04L1/06

摘要： Spatial spreading is performed in a multi-antenna system to randomize an “effective” channel observed by a receiving entity for each transmitted data symbol block. For a MIMO system, at a transmitting entity, data is processed (e.g., encoded, interleaved, and modulated) to obtain ND data symbol blocks to be transmitted in NM transmission spans, where ND≧1 and NM>1. The ND blocks are partitioned into NM data symbol subblocks, one subblock for each transmission span. A steering matrix is selected (e.g., in a deterministic or pseudo-random manner from among a set of L steering matrices, where L>1) for each subblock. Each data symbol subblock is spatially processed with the steering matrix selected for that subblock to obtain transmit symbols, which are further processed and transmitted via NT transmit antennas in one transmission span. The ND data symbol blocks are thus spatially processed with NM steering matrices and observe an ensemble of channels.

摘要翻译： 在多天线系统中执行空间扩展，以随机化接收实体针对每个发送的数据符号块观察到的“有效”信道。 对于MIMO系统，在发送实体处理（例如，编码，交织和调制）数据以获得N N个数据符号块，以在N M M中发送。 传输范围，其中N = 1和N M M 1。 N N个块被划分为N个M个数据符号子块，每个传输跨度的一个子块。 对于每个子块，选择导向矩阵（例如，以确定性或伪随机方式从一组L个导引矩阵中，其中L> 1）。 利用为该子块选择的导引矩阵来对每个数据符号子块进行空间处理，以获得在一个传输跨度中通过N T个发射天线进一步处理和传输的发射符号。 N N个数据符号块因此用N M M导引矩阵进行空间处理并观察信道的整体。

公开(公告)号：US20050159735A1

公开(公告)日：2005-07-21

申请号：US10888804

申请日：2004-07-09

申请人： Jay Walton ,  Lizhong Zheng ,  John Ketchum ,  Mark Wallace ,  Steven Howard

发明人： Jay Walton ,  Lizhong Zheng ,  John Ketchum ,  Mark Wallace ,  Steven Howard

IPC分类号： A61B17/00 ,  A61B18/02 ,  A61F7/00 ,  A61F7/10 ,  A61F7/12 ,  A61M25/00 ,  F25B9/02

CPC分类号： F25D3/10 ,  A61B18/02 ,  A61B2017/00199 ,  A61B2018/0212 ,  A61B2018/0262 ,  A61B2018/0268 ,  F25B9/02 ,  F25B2700/13 ,  F25D16/00 ,  F25D2400/36

摘要： An apparatus and method for automatic operation of a refrigeration system to provide refrigeration power to a catheter for tissue ablation or mapping. The primary refrigeration system can be open loop or closed loop, and a precool loop will typically be closed loop. Equipment and procedures are disclosed for bringing the system to the desired operational state, for controlling the operation by controlling refrigerant flow rate, for performing safety checks, and for achieving safe shutdown. The catheter-based system for performing a cryoablation procedure uses a precooler to lower the temperature of a fluid refrigerant to a sub-cool temperature (−40° C.) at a working pressure (400 psi). The sub-cooled fluid is then introduced into a supply line of the catheter. Upon outflow of the primary fluid from the supply line, and into a tip section of the catheter, the fluid refrigerant boils at an outflow pressure of approximately one atmosphere, at a temperature of about −88° C. In operation, the working pressure is computer controlled to obtain an appropriate outflow pressure for the coldest possible temperature in the tip section.

摘要翻译： 一种用于自动操作制冷系统以向用于组织消融或映射的导管提供制冷功率的装置和方法。 主要制冷系统可以是开环或闭环，并且预冷循环通常将是闭环的。 公开了用于使系统达到所需操作状态的设备和程序，用于通过控制制冷剂流量来控制操作，用于执行安全检查和实现安全关闭。 用于执行冷冻消融程序的基于导管的系统使用预冷器来在工作压力（400psi）下将流体制冷剂的温度降低至亚冷的温度（-40℃）。 然后将次冷流体引入导管的供应管线。 在主要流体从供应管路流出并进入导管的尖端部分时，流体制冷剂在大约一个大气压的流出压力下沸腾，温度约为-88℃。在操作中，工作压力为 计算机控制以获得适当的流出压力，用于在尖端部分中最冷的温度。