公开(公告)号：US5828957A

公开(公告)日：1998-10-27

申请号：US615937

申请日：1996-03-14

申请人： Brian W. Kroeger ,  Gregory W. Seker ,  Paul J. Peyla ,  George N. Eberl ,  Denise M. Cammarata

发明人： Brian W. Kroeger ,  Gregory W. Seker ,  Paul J. Peyla ,  George N. Eberl ,  Denise M. Cammarata

IPC分类号： H04B7/185 ,  H04Q7/00

CPC分类号： H04B7/18545 ,  H04B7/18539

摘要： An improved satellite beam acquisition and crossover technique for finding an appropriate satellite beam by searching for and acquiring a strongest pilot channel, searching for signalling channels on the acquired strongest pilot channel and monitoring the acquired signalling channel. Beam acquisition of a continuous wave pilot as in the preferred embodiment is faster and more reliable than beam acquisition of a modulated channel. Moreover, the acquired pilot channel can be used to unambiguously precalibrate the frequency reference of the mobile terminal. Also, acquisition of the pilot ensures that the corresponding satellite beam is not blocked or shadowed immediately prior to searching for a signalling channel, which significantly improves the reliability while reducing the time required for the search process. Mitigation of fading and shadowing is provided by using fast attack, slow decay non-linear filtering.

摘要翻译： 通过搜索和获取最强导频信道，搜索所获得的最强导频信道上的信令信道并监测所获取的信令信道，来改进卫星波束获取和交叉技术，以找到适当的卫星波束。 如在优选实施例中的连续波导导的光束采集比调制信道的光束采集更快更可靠。 此外，获取的导频信道可以用于明确地预校准移动终端的频率参考。 此外，采集导频确保相应的卫星波束在搜索信令信道之前不被立即阻塞或遮蔽，这显着提高了可靠性，同时减少了搜索过程所需的时间。 通过使用快速攻击，慢衰减非线性滤波来提供衰减和遮蔽的缓解。

公开(公告)号：US5828705A

公开(公告)日：1998-10-27

申请号：US593154

申请日：1996-02-01

申请人： Brian W. Kroeger ,  Jeffrey S. Baird

发明人： Brian W. Kroeger ,  Jeffrey S. Baird

IPC分类号： H04L27/00 ,  H04L27/233 ,  H04L27/14 ,  H04L27/16 ,  H04L27/22

CPC分类号： H04L27/2332 ,  H04L2027/003 ,  H04L2027/0057 ,  H04L2027/0067 ,  H04L2027/0073

摘要： The carrier tracking loop technique and apparatus provides smooth, accurate frequency tracking, fast reacquisition and doppler tracking over a wide dynamic range. The loop parameters of the carrier tracking loop are varied as a function of mode, i.e. flywheel, tracking or reacquisition modes. The various modes of operation are automatically detected and loop operation is enhanced by non-linear techniques. The enhancements include fourth power sample normalization to improve performance over a large dynamic range and to ease fixed point scaling. A slope limiter is included which aids in coherent detection by reducing phase noise introduced by the carrier tracking loop. Also, a predifferentiation filter further aids in coherent detection by reducing phase noise.

摘要翻译： 载波跟踪环路技术和装置在宽动态范围内提供平稳，准确的频率跟踪，快速重新采集和多普勒跟踪。 作为模式的函数，即飞轮，跟踪或重新获取模式，载波跟踪环路的循环参数是变化的。 自动检测各种操作模式，通过非线性技术增强循环操作。 增强功能包括第四次功率样本归一化，以提高在大动态范围内的性能，并简化固定点缩放。 包括一个斜率限制器，通过减少由载波跟踪环路引入的相位噪声来帮助进行相干检测。 此外，预分化滤波器还通过减少相位噪声来辅助相干检测。

公开(公告)号：US5684835A

公开(公告)日：1997-11-04

申请号：US322846

申请日：1994-10-13

申请人： Brian W. Kroeger ,  Joseph B. Bronder ,  Jeffrey S. Baird

发明人： Brian W. Kroeger ,  Joseph B. Bronder ,  Jeffrey S. Baird

IPC分类号： H04L27/00 ,  H04L27/233 ,  H03D3/22 ,  H04L27/22

CPC分类号： H04L27/2332 ,  H04L2027/003 ,  H04L2027/0048

摘要： A locally coherent Quadrature Phase Shift Keying (QPSK) detector that uses a normalized fourth power weighting technique to generate an ambiguous local phase reference of a current symbol. A phase adjusted previous symbol reference is used to resolve the ambiguity using differentially coded data and yield current soft symbol information.

摘要翻译： 本地相干正交相移键控（QPSK）检测器，其使用归一化的第四功率加权技术来产生当前符号的模糊的局部相位参考。 使用相位调整的先前符号参考来使用差分编码数据解析模糊度并且产生当前软符号信息。

公开(公告)号：US5566214A

公开(公告)日：1996-10-15

申请号：US491667

申请日：1995-06-19

申请人： Brian W. Kroeger ,  Jeffrey S. Baird

发明人： Brian W. Kroeger ,  Jeffrey S. Baird

IPC分类号： H04L27/22 ,  H04L7/00

CPC分类号： H04L27/22

摘要： A QPSK demodulator symbol tracking loop including automatic noise normalization and reacquisition control enables improved symbol tracking and acquisition during fading or intermittent channel conditions. A noise variance estimate is determined and the symbol tracking loop flywheels when the signal level dips below a flywheel threshold relative to the noise variance estimate during fading or intermittent channel conditions. Determination in advance of an absolute power level of the thermal noise floor of analog front end components is dispensed with and precise control of the gain and noise level of the analog front end components is not needed, thus simplifying design. A reacquisition mode is declared upon determination of an abrupt increase in signal level indicative of emergence from a fading condition or upon detection of an excessive symbol tracking error signal. During the reacquisition mode, the loop gain of the symbol tracking loop is temporarily increased to improve reacquisition time.

摘要翻译： 包括自动噪声归一化和重新获取控制的QPSK解调器符号跟踪环能够在衰落或间歇信道条件下改进符号跟踪和采集。 确定噪声方差估计，并且当信号电平在衰落或间歇信道条件期间相对于噪声方差估计下降到飞轮阈值以下时，符号跟踪环路飞行。 模拟前端部件的热噪声基底的绝对功率水平之前的确定被省略，并且不需要对模拟前端部件的增益和噪声电平的精确控制，从而简化了设计。 在确定指示从衰落状态出现或者在检测到过多的符号跟踪误差信号的信号电平突然增加时，声明重新获取模式。 在重新获取模式期间，暂时增加符号跟踪循环的环路增益，以提高重新获取时间。

公开(公告)号：US5404375A

公开(公告)日：1995-04-04

申请号：US110265

申请日：1993-08-23

申请人： Brian W. Kroeger ,  Richard E. Martinson

发明人： Brian W. Kroeger ,  Richard E. Martinson

IPC分类号： H04B7/216 ,  H04K1/00

CPC分类号： H04B7/216

摘要： A system for transmitting and receiving outbound and inbound data signals through a satellite communications network, the system having a network data rate and including a satellite and an end user transceiver, the system comprising a half-duplex mobile transceiver for transmitting and receiving the inbound and outbound data signals, respectively, for spreading the inbound data signal from the network data rate to a reduced data rate having an increased signal-to-noise ratio using a spread sequence, and for despreading the outbound data signal from the reduced data rate to the network data rate. The system also comprises an earth station, coupled to the end user transceiver, for transmitting and receiving the outbound and inbound data signals, wherein the earth station includes means for spreading the outbound data signal from the network data rate to the reduced data rate using the spread sequence, and means for despreading the inbound data signal from the reduced data rate to the network data rate, and wherein the end-user transceiver includes means for transmitting the outbound data signal and for receiving the inbound data signal.

摘要翻译： 一种用于通过卫星通信网络发送和接收出站和入站数据信号的系统，该系统具有网络数据速率，并且包括卫星和终端用户收发信机，该系统包括用于发送和接收入站和接收的半双工移动收发信机 用于将入站数据信号从网络数据速率扩展到使用扩展序列具有增加的信噪比的降低的数据速率的出站数据信号，并且用于将出站数据信号从减小的数据速率解扩到 网络数据速率。 该系统还包括耦合到最终用户收发信机的用于发送和接收出站和入站数据信号的地球站，其中，地球站包括用于使用所述网络数据速率将出站数据信号从网络数据速率扩展到降低的数据速率的装置 扩展序列，以及用于将入站数据信号从减小的数据速率解扩到网络数据速率的装置，并且其中终端用户收发器包括用于发送出站数据信号和用于接收入站数据信号的装置。

公开(公告)号：US4937828A

公开(公告)日：1990-06-26

申请号：US267404

申请日：1988-11-04

申请人： Hubert Shih ,  Brian W. Kroeger ,  Robert J. Delcoco

发明人： Hubert Shih ,  Brian W. Kroeger ,  Robert J. Delcoco

IPC分类号： H03M13/09

CPC分类号： H03M13/091

摘要： A cyclic redundancy check generator for a high speed data bus is capable of outputting frames of data and cyclic redundancy check bits concatenated together without any additional space or time delay between frames while operating at a normal clock speed. Data to be transmitted is parallel loaded into series-connected registers via multiplexers connected between the registers. The multiplexers also provide parallel loading of the cyclic redundancy check bits for a frame of data from a look-ahead cyclic redundancy check logic circuit. The output of the logic circuit is also connected to a cyclic redundancy check register. The logic circuit has inputs connected to the final series-connected data register and the cyclic redundancy check register. The logic circuit operates on portions of words in a frame of data and when the last portion of the last word has been processed, the output from the logic circuit is selected by the multiplexers and then shifted out of the data registers immediately behind the last word of the frame. After the last portion of the cyclic redundancy check bits have been output from the final register, the first word in the next frame is parallel loaded into the registers and the cyclic redundancy check register is initialized so that processing of the first word of the next frame can begin in the logic circuit.

摘要翻译： 用于高速数据总线的循环冗余校验发生器能够在以正常时钟速度操作的同时在帧之间输出数据帧和循环冗余校验位，而不会在帧之间任何额外的空间或时间延迟。 要发送的数据通过连接在寄存器之间的复用器并行加载到串联寄存器中。 多路复用器还提供来自前瞻循环冗余校验逻辑电路的数据帧的循环冗余校验位的并行加载。 逻辑电路的输出也连接到循环冗余校验寄存器。 逻辑电路具有连接到最终串联数据寄存器和循环冗余校验寄存器的输入。 逻辑电路对数据帧中的字的部分进行操作，当最后一个字的最后部分被处理时，逻辑电路的输出由多路复用器选择，然后从最后一个字后面的数据寄存器中移出 的框架。 在从最终寄存器输出循环冗余校验位的最后部分之后，下一帧中的第一个字被并行加载到寄存器中，循环冗余校验寄存器被初始化，以便处理下一帧的第一个字 可以在逻辑电路中开始。