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    Efficient communication channel survey
    1.
    发明授权
    Efficient communication channel survey 有权
    高效沟通渠道调查

    公开(公告)号：US07995547B1

    公开(公告)日：2011-08-09

    申请号：US12790720

    申请日：2010-05-28

    申请人： Craig H. Barratt

    发明人： Craig H. Barratt

    IPC分类号： H04W4/00

    CPC分类号： H04W48/16

    摘要： A system and method are described for repeatedly and efficiently performing a wireless communication channel survey to determine whether comparable communications devices exist, which frequencies are in use, and the identities of the comparable communications devices. A beacon data table stores received beacon data which is used to predict beacon arrival times, thereby allowing a receiver to be tuned away from an active data communications channel for a shorter dwell time than a beacon period. A further efficiency can be gained if beacon generators cooperatively stagger their beacon times according to one or more measurable characteristics of the beacon generator, e.g. the operating channel number and the SSID.

    摘要翻译： 描述了用于重复和有效地执行无线通信信道调查以确定是否存在可比较的通信设备，哪些频率正在使用的系统和方法以及可比较的通信设备的标识。 信标数据表存储用于预测信标到达时间的接收到的信标数据，从而允许接收机远离活动数据通信信道远离信标周期更短的驻留时间。 如果信标发生器根据信标发生器的一个或多个可测量的特性协作地交错它们的信标时间，则可获得进一步的效率。 操作通道号和SSID。

    Efficient communication channel survey
    2.
    发明授权
    Efficient communication channel survey 有权
    高效沟通渠道调查

    公开(公告)号：US07768960B1

    公开(公告)日：2010-08-03

    申请号：US10896294

    申请日：2004-07-20

    申请人： Craig H. Barratt

    发明人： Craig H. Barratt

    IPC分类号： H04W4/00

    CPC分类号： H04W48/16

    摘要： A system and method are described for repeatedly and efficiently performing a wireless communication channel survey to determine whether comparable communications devices exist, which frequencies are in use, and the identities of the comparable communications devices. A beacon data table stores received beacon data which is used to predict beacon arrival times, thereby allowing a receiver to be tuned away from an active data communications channel for a shorter dwell time than a beacon period. A further efficiency can be gained if beacon generators cooperatively stagger their beacon times according to one or more measurable characteristics of the beacon generator, e.g. the operating channel number and the SSID.

    摘要翻译： 描述了用于重复和有效地执行无线通信信道调查以确定是否存在可比较的通信设备，哪些频率正在使用的系统和方法以及可比较的通信设备的标识。 信标数据表存储用于预测信标到达时间的接收到的信标数据，从而允许接收机远离活动数据通信信道远离信标周期更短的驻留时间。 如果信标发生器根据信标发生器的一个或多个可测量的特性协作地交错它们的信标时间，则可获得进一步的效率。 操作通道号和SSID。

    Apparatus and method for creating non-orthogonal magnetic resonance imaging
    3.
    发明授权
    Apparatus and method for creating non-orthogonal magnetic resonance imaging 失效
    用于产生非正交磁共振成像的装置和方法

    公开(公告)号：US4743851A

    公开(公告)日：1988-05-10

    申请号：US89941

    申请日：1987-08-25

    申请人： Arthur J. Lim ,  Michael H. Buonocore ,  Craig H. Barratt

    发明人： Arthur J. Lim ,  Michael H. Buonocore ,  Craig H. Barratt

    IPC分类号： G01N24/08 ,  G01R33/385 ,  G01R33/54 ,  G01R33/20

    CPC分类号： G01R33/56518 ,  G01N24/08 ,  G01R33/4833

    摘要： In an improved NMR imaging method for forming images of a subject by determining the relative densities of nuclei within the subject, three orthogonal gradient fields are generated by digitally storing three gradient waveforms for each orthogonal direction, with each waveform being individually compensated and calibrated with respect to an axis with which it is associated. Nine associated matrix multiplying functions which determine the coordinates of a desired slice in its rotated plane are also stored by an external input (by computer or by the clinician operating the system.) Then, in a sequential fashion, digital words for each gradient waveform are read out, multiplied by pairs with the appropriate multiplying function and the three terms are added to form a digital word. These words are converted to an analog value and applied to the respective gradient coils.

    摘要翻译： 在用于通过确定受试者中核的相对密度来确定受试者的图像的改进的NMR成像方法中，通过对每个正交方向数字地存储三个梯度波形来产生三个正交梯度场，每个波形被单独地补偿和校准， 与其相关联的轴。 确定其旋转平面中期望切片的坐标的九个相关联的矩阵乘法函数也由外部输入（由计算机或由操作系统的临床医师）存储。然后，以顺序的方式，每个梯度波形的数字字是 读出，乘以具有适当乘法函数的对，并且添加三个项以形成数字字。 将这些字转换为模拟值并应用于各个梯度线圈。

    Quantization error reduction method for phase encode gradient in NMR imaging
    4.
    发明授权
    Quantization error reduction method for phase encode gradient in NMR imaging 失效
    NMR成像中相位编码梯度的量化误差降低方法

    公开(公告)号：US4713615A

    公开(公告)日：1987-12-15

    申请号：US890594

    申请日：1986-07-25

    申请人： Craig H. Barratt ,  Brian P. Wilfley ,  David M. Parish

    发明人： Craig H. Barratt ,  Brian P. Wilfley ,  David M. Parish

    IPC分类号： G01R33/54 ,  G01R33/20

    CPC分类号： G01R33/482

    摘要： In an improved NMR imaging method, where three-nominally orthogonal gradient fields are generated, the quantization error of the phase encode gradient is reduced without the necessity of a digital to analog converter of higher bit capacity. This is accomplished in one embodiment by providing a second smaller gradient waveform which is relatively narrow compared to the primary gradient waveform, the ratio of the waveforms being proportional to the improved resolution. The second waveform can occur either before or after the 180.degree. excitation pulse used to produce a spin-echo signal. In another embodiment pulse width modulation is used to vary the area of the phase encode waveform in discrete increments.

    摘要翻译： 在一种改进的NMR成像方法中，在产生三个名义上的正交梯度场的情况下，减少了相位编码梯度的量化误差，而不需要具有较高位容量的数模转换器。 这在一个实施例中通过提供与主梯度波形相比较窄的第二较小梯度波形来实现，波形与改进的分辨率成比例。 第二波形可以在用于产生自旋回波信号的180°激发脉冲之前或之后发生。 在另一实施例中，脉冲宽度调制用于以离散增量改变相位编码波形的面积。

    Determining a calibration function using at least one remote terminal
    7.
    发明授权
    Determining a calibration function using at least one remote terminal 有权
    使用至少一个远程终端确定校准功能

    公开(公告)号：US06654590B2

    公开(公告)日：2003-11-25

    申请号：US10136049

    申请日：2002-04-29

    申请人： Tibor Boros ,  Craig H. Barratt ,  Christopher R. Uhlik ,  Mitchell D. Trott

    发明人： Tibor Boros ,  Craig H. Barratt ,  Christopher R. Uhlik ,  Mitchell D. Trott

    IPC分类号： H04B1700

    CPC分类号： H04L25/03343 ,  H01Q1/246 ,  H01Q3/2605 ,  H01Q3/267 ,  H04B7/005 ,  H04B7/0615 ,  H04B7/0617 ,  H04B7/0842 ,  H04B7/0848 ,  H04B17/10 ,  H04B17/11 ,  H04B17/12 ,  H04B17/14 ,  H04B17/21 ,  H04L2025/03426

    摘要： A calibration function for calibrating a base station can be determined using one or more remote terminals. In one embodiment of the present invention, determining the calibration function includes transmitting a calibration signal, using an array of antenna elements of a first radio, to a second radio, and receiving, at the first radio, a downlink spatial signature related signal from the second radio containing information related to a second radio downlink spatial signature, the information being calculated using the calibration signal. Then, a second radio downlink spatial signature may be determined using the downlink spatial signature related signal. Also, a second radio uplink spatial signature may be determined using an uplink spatial signature signal from the second radio to the first radio. The calibration function may then be determined using the second radio downlink spatial signature and the second radio uplink spatial signature. Furthermore, one embodiment of the present invention may include determining a third radio downlink weight vector for a third radio using a third radio uplink weight vector and the calibration function.

    摘要翻译： 用于校准基站的校准功能可以使用一个或多个远程终端来确定。 在本发明的一个实施例中，确定校准功能包括使用第一无线电的天线元件的阵列向第二无线电发射校准信号，并且在第一无线电处接收来自第一无线电的下行链路空间签名相关信号 所述第二无线电装置包含与第二无线电下行链路空间签名有关的信息，所述信息使用所述校准信号来计算。 然后，可以使用下行链路空间签名相关信号来确定第二无线电下行链路空间特征。 此外，可以使用从第二无线电到第一无线电的上行链路空间签名信号来确定第二无线电上行链路空间签名。 然后可以使用第二无线电下行链路空间签名和第二无线电上行链路空间签名来确定校准功能。 此外，本发明的一个实施例可以包括使用第三无线电上行链路权重向量和校准功能确定第三无线电的第三无线电下行链路权重向量。

    Method and apparatus for determining signatures for calibrating a communication station having an antenna array
    8.
    发明授权
    Method and apparatus for determining signatures for calibrating a communication station having an antenna array 有权
    用于确定用于校准具有天线阵列的通信站的签名的方法和装置

    公开(公告)号：US06615024B1

    公开(公告)日：2003-09-02

    申请号：US09295434

    申请日：1999-04-20

    申请人： Tibor Boros ,  Craig H. Barratt ,  Christopher R. Uhlik ,  Mitchell D. Trott

    发明人： Tibor Boros ,  Craig H. Barratt ,  Christopher R. Uhlik ,  Mitchell D. Trott

    IPC分类号： H04B1700

    CPC分类号： H04L25/03343 ,  H01Q1/246 ,  H01Q3/2605 ,  H01Q3/267 ,  H04B7/005 ,  H04B7/0615 ,  H04B7/0617 ,  H04B7/0842 ,  H04B7/0848 ,  H04B17/10 ,  H04B17/11 ,  H04B17/12 ,  H04B17/14 ,  H04B17/21 ,  H04L2025/03426

    摘要： A method and apparatus for estimating the downlink signature for a remote transceiver which is part of a wireless communication system that includes a main transceiver for communicating with the remote transceiver. The main transceiver includes an array of transmit antenna elements. The method uses the remote transceiver for receiving signals when the main transceiver transmits downlink calibration signals. When the main transceiver also has a receive antenna array, the remote transceiver can transmit uplink calibration signals to the main transceiver for determining an uplink signature. The downlink and uplink signatures are used to determine a calibration function to account for differences in the apparatus chains that include the antenna elements of the arrays, and that enable downlink smart antenna processing weights to be determined from uplink smart antenna processing weights when the main transceiver includes means for smart antenna processing according to weights.

    摘要翻译： 一种用于估计作为包括用于与远程收发信机进行通信的主收发器的无线通信系统的一部分的远程收发器的下行链路签名的方法和装置。 主收发器包括发射天线元件阵列。 当主收发器发送下行链路校准信号时，该方法使用远程收发器来接收信号。 当主收发器还具有接收天线阵列时，远程收发器可以向主收发器发送上行链路校准信号以确定上行链路签名。 下行链路和上行链路签名用于确定校准功能以考虑包括阵列的天线元件的装置链中的差异，并且当主收发机（20）在上行智能天线处理权重中确定下行链路智能天线处理权重时 包括根据权重进行智能天线处理的装置。

    Method and apparatus for calibrating radio frequency base stations using antenna arrays
    9.
    发明授权
    Method and apparatus for calibrating radio frequency base stations using antenna arrays 失效
    使用天线阵列校准射频基站的方法和装置

    公开(公告)号：US6037898A

    公开(公告)日：2000-03-14

    申请号：US948772

    申请日：1997-10-10

    申请人： David M. Parish ,  Farhad Farzaneh ,  Craig H. Barratt

    发明人： David M. Parish ,  Farhad Farzaneh ,  Craig H. Barratt

    IPC分类号： H01Q3/26 ,  H04W24/00 ,  G01S13/00

    CPC分类号： H04W24/00 ,  H01Q3/267

    摘要： A method operating in a communications station for calibrating the communications station, the communications station including an antenna array of antenna elements, each having associated with it and included in a transmit apparatus chain and a receiver apparatus chain. The method comprises transmitting a prescribed signal from each antenna element using the transmit apparatus chain associated with the antenna element while receiving the transmitted signal in receiver apparatus chains not associated with the antenna. Calibration factors for each antenna element are determined as dependent on the associated transmit apparatus chain and receiver apparatus chain transfer functions using the prescribed signal and each of the signals received during transmissions. A communications station also is described which includes: an antenna array of a plurality of elements, each antenna element having associated with it and included in a transmit apparatus chain and a receiver apparatus chain; transmitting means configured to transmit a prescribed signal from each antenna element while receiving the transmitted signal in at least one receiver apparatus chain not associated with the transmitting antenna element; a memory coupled to the receiver apparatus chains for storing the signals received during the transmissions of the prescribed signals; and a signal processor coupled to the memory and configured to determine calibration factors for each antenna element, the calibration factors for a particular antenna element based on the transmit apparatus chain and receiver apparatus chain transfer functions of the transmit and receiver apparatus chains, respectively, that are associated with the particular antenna element.

    摘要翻译： 一种在通信站中操作的用于校准通信站的方法，所述通信站包括天线阵列天线阵列，每个天线阵列与天线阵列相关联并包括在发射设备链和接收机设备链中。 该方法包括使用与天线元件相关联的发射装置链从每个天线元件发送规定的信号，同时在与天线不相关的接收机装置链中接收发射信号。 每个天线元件的校准因子被确定为取决于相关联的发射设备链和接收机设备链传递函数，使用规定的信号和传输期间接收到的每个信号。 还描述了一种通信站，其包括：多个元件的天线阵列，每个天线元件与其相关联并且被包括在发射设备链和接收机设备链中; 发送装置，被配置为在与所述发送天线元件不相关联的至少一个接收机设备链路中接收所发送的信号的同时从每个天线元件发送规定的信号; 耦合到所述接收机设备链的存储器，用于存储在所述规定信号的传输期间接收到的信号; 以及信号处理器，其耦合到所述存储器并且被配置为基于所述发射装置链和所述发射装置链的接收装置链传送功能，分别确定每个天线元件的校准因子，特定天线元件的校准因子， 与特定天线元件相关联。