公开(公告)号：US5732113A

公开(公告)日：1998-03-24

申请号：US666237

申请日：1996-06-20

申请人： Timothy M. Schmidl ,  Donald C. Cox

发明人： Timothy M. Schmidl ,  Donald C. Cox

IPC分类号： H04L27/26 ,  H04L7/00

CPC分类号： H04L5/0048 ,  H04L27/2613 ,  H04L27/2657 ,  H04L27/2662 ,  H04L27/2675

摘要： A method and apparatus achieves rapid timing synchronization, carrier frequency synchronization, and sampling rate synchronization of a receiver to an orthogonal frequency division multiplexed (OFDM) signal. The method uses two OFDM training symbols to obtain full synchronization in less than two data frames. A first OFDM training symbol has only even-numbered sub-carriers, and substantially no odd-numbered sub-carriers, an arrangement that results in half-symbol symmetry. A second OFDM training symbol has even-numbered sub-carriers differentially modulated relative to those of the first OFDM training symbol by a predetermined sequence. Synchronization is achieved by computing metrics which utilize the unique properties of these two OFDM training symbols. Timing synchronization is determined by computing a timing metric which recognizes the half-symbol symmetry of the first OPDM training symbol. Carrier frequency offset estimation is performed in using the timing metric as well as a carrier frequency offset metric which peaks at the correct value of carrier frequency offset. Sampling rate offset estimation is performed by evaluating the slope of the locus of points of phase rotation due to sampling rate offset as a function of sub-carrier frequency number.

摘要翻译： 一种方法和装置实现了接收机到正交频分复用（OFDM）信号的快速定时同步，载波频率同步和采样率同步。 该方法使用两个OFDM训练符号在少于两个数据帧中获得完全同步。 第一OFDM训练符号仅具有偶数子载波，并且基本上没有奇数子载波，导致半符号对称的布置。 第二OFDM训练符号具有相对于第一OFDM训练符号的预定序列差分调制的偶数子载波。 通过计算利用这两个OFDM训练符号的独特属性的度量来实现同步。 通过计算识别第一OPDM训练符号的半符号对称性的定时度量来确定定时同步。 使用定时度量以及在载波频率偏移的正确值处达到峰值的载波频率偏移度量来执行载波频率偏移估计。 通过对作为副载波频数的函数的采样率偏移量的相位旋转点的轨迹的斜率进行评估来进行采样率偏移估计。

公开(公告)号：US06546055B1

公开(公告)日：2003-04-08

申请号：US09229453

申请日：1999-01-12

申请人： Timothy M. Schmidl ,  Donald C. Cox

发明人： Timothy M. Schmidl ,  Donald C. Cox

IPC分类号： H04B110

CPC分类号： H04L27/2676 ,  H04L27/2607 ,  H04L27/2659

摘要： A method of determining an integral portion of a carrier offset &Dgr;fc of an RF signal transmitted from a transmitter at a transmit carrier frequency fct and an apparatus for carrying out the method. The signal consists of at least two data symbols S1 and S2, each having a useful part preceded by a cyclic prefix containing a tail portion of the useful part, such that in the time domain the useful part occupies a symbol interval Ts and the cyclic prefix occupies a guard interval Tg. The carrier offset &Dgr;fc between a receive carrier frequency fcr and the transmit carrier frequency fct is calculated in the form of an integral multiple of the inverse 1/Ts of the symbol interval. The method is especially useful in application to data symbols which are multiplexed by the orthogonal frequency division multiplexing (OFDM) and are constructed from sub-symbols ck belonging to a 2m-ary constellation of complex values equally spaced in phase, such as phase-shift keyed (PSK) constellations, e.g., BPSK, QPSK, DQPSK, 8-PSK, 8-DPSK, 16-PSK and 16-DPSK or amplitude and phase-shift keyed (APSK) constellations, e.g., 16-APSK, 16-DAPSK, 64-APSK and 64-DAPSK.

摘要翻译： 确定从发射机在发射载波频率fct发射的RF信号的载波偏移量DELTAfc的积分部分的方法和用于执行该方法的装置。 该信号由至少两个数据符号S1和S2组成，每个数据符号具有一个有用的部分，前面是包含有用部分的尾部的循环前缀，使得在时域中有用部分占据符号间隔Ts和循环前缀 保持间隔Tg。 以符号间隔的倒数1 / Ts的整数倍的形式计算接收载波频率fcr与发射载波频率fct之间的载波偏移量ΔTATAfc。 该方法在应用于通过正交频分复用（OFDM）复用的数据符号中是特别有用的，并且是由属于相等间隔相位的复数值的2m元构象的子符号ck构成的，例如相移 键控（PSK）星座，例如BPSK，QPSK，DQPSK，8-PSK，8-DPSK，16-PSK和16-DPSK或幅度和相移键控（APSK）星座，例如16-APSK，16-DAPSK ，64-APSK和64-DAPSK。

公开(公告)号：US6128724A

公开(公告)日：2000-10-03

申请号：US988703

申请日：1997-12-11

申请人： Tsung-En Andy Lee ,  Donald C. Cox

发明人： Tsung-En Andy Lee ,  Donald C. Cox

IPC分类号： G06F9/30 ,  G06F9/38 ,  G06F15/00

CPC分类号： G06F9/3802 ,  G06F9/3012 ,  G06F9/30138 ,  G06F9/3822 ,  G06F9/3824 ,  G06F9/3889 ,  Y02B60/50

摘要： A micro-computer is arranged to execute instructions for data intensive applications, such as those used in mobile communications. One particular embodiment involves processing instructions into computational codes and data management codes. These two parts are coded separately and issued to two different program decoders in parallel. Computational codes control the computational units with register-to-register data movement only. Data management codes control data movement through the data management unit to prepare and transfer data for the computation. Multiple register files with active file swapping scheme may be used to simplify the computational operations without decreasing performance. The arrangement provides a significant reduction in power and is, therefore, especially advantageous for battery-operated communication applications and devices.

摘要翻译： 微计算机被布置成执行用于数据密集型应用的指令，诸如在移动通信中使用的那些。 一个特定实施例涉及将指令处理成计算代码和数据管理代码。 这两个部分分别编码并并行发布给两个不同的程序解码器。 计算代码仅使用寄存器到寄存器数据移动来控制计算单元。 数据管理代码通过数据管理单元控制数据移动，以准备和传送用于计算的数据。 可以使用具有活动文件交换方案的多个寄存器文件来简化计算操作而不降低性能。 该装置显着降低功率，因此对于电池供电的通信应用和设备尤其有利。

公开(公告)号：US4462004A

公开(公告)日：1984-07-24

申请号：US359220

申请日：1982-03-18

申请人： Donald C. Cox ,  Adel A. M. Saleh

发明人： Donald C. Cox ,  Adel A. M. Saleh

IPC分类号： H03F3/19 ,  H03F1/02 ,  H03F3/16 ,  H03G3/10

CPC分类号： H03F1/0266 ,  H03F1/0261 ,  H03F2200/102 ,  H03F2200/18 ,  H03F2200/192

摘要： The present invention relates to a linear, class A FET amplifier circuit capable of providing linear amplifier of input signals with a time-varying envelope function. An envelope detector (12) is responsive to an input signal (v.sub.i (t)) for extracting the envelope signal (V.sub.i (t)) therefrom. A gate controller (16) subsequently adds the envelope signal to a predetermined gate bias voltage (E.sub.G) and applies the sum (E.sub.G (t)) as the "d-c" gate input to the FET amplifier (14). Therefore, the gate bias voltage is dynamically controlled by the envelope of the input signal, resulting in a significant improvement in the power-added efficiency (.eta..sub.added) over prior art class A FET amplifiers.

摘要翻译： 本发明涉及能够提供具有时变包络函数的输入信号的线性放大器的线性A类FET放大器电路。 包络检测器（12）对输入信号（vi（t））作出响应，以从中提取包络信号（Vi（t））。 门控制器（16）随后将包络信号添加到预定的栅极偏置电压（EG），并将和（EG（t））作为“d-c”门输入施加到FET放大器（14）。 因此，栅极偏置电压由输入信号的包络动态地控制，导致与现有技术的A类FET放大器相比，功率附加效率（eta）的显着改善。

公开(公告)号：US09001923B2

公开(公告)日：2015-04-07

申请号：US13666820

申请日：2012-11-01

申请人： Donald C. Cox ,  Thomas G. McGiffen

发明人： Donald C. Cox ,  Thomas G. McGiffen

IPC分类号： H04L27/00 ,  H04B17/00 ,  H04L1/00 ,  H04L1/06 ,  H04L1/20

CPC分类号： H04B17/309 ,  H04B17/373 ,  H04L1/0003 ,  H04L1/0006 ,  H04L1/0009 ,  H04L1/0019 ,  H04L1/06 ,  H04L1/203

摘要： Methods and apparatus, including computer program products, are provided performance prediction. In one aspect there is provided a method. The method may include receiving information including one or more of a set of weights, a set of events, and a channel estimate, wherein at least one of the set of weights and the set of events are determined based on a optimization; and determining a transmitter configuration by performing at least one of: applying the set of weights to a set of pair wise error probabilities to determine a set of predicted bit error rates, and applying the set of events to the set of pair wise error probabilities to determine a set of predicted packet error rates. Related apparatus, systems, methods, and articles are also described.

摘要翻译： 方法和设备，包括计算机程序产品，都提供了性能预测。 在一个方面，提供了一种方法。 该方法可以包括接收包括一组权重，一组事件和信道估计中的一个或多个的信息，其中基于优化确定权重集和事件集合中的至少一个; 以及通过执行以下各项中的至少一个来确定发射机配置：将所述权重集合应用于一组成对误差概率，以确定一组预测的比特误码率，以及将所述一组事件应用于所述一对成对误差概率，以 确定一组预测的分组错误率。 还描述了相关装置，系统，方法和制品。

公开(公告)号：US4513412A

公开(公告)日：1985-04-23

申请号：US488397

申请日：1983-04-25

申请人： Donald C. Cox

发明人： Donald C. Cox

IPC分类号： H04B7/04 ,  H04B7/02 ,  H04B7/06 ,  H04B7/08 ,  H04B7/10 ,  H04B7/26

CPC分类号： H04B7/10 ,  H04B7/061 ,  H04B7/0811 ,  H04B7/2643

摘要： The present invention relates to a portable transceiver and a remote terminal station each using at least two antennas with different polarization transmission capabilities for an adaptive retransmission technique. In the present adaptive retransmission technique, the terminal station transmits the same preamble signal in at least two time slots of a frame period of a time division sequence using the antenna receiving the strongest signal from the transceiver in the immediately prior frame period followed by a binary message signal using the same antenna. The transceiver receives each of the preamble transmissions from the terminal station via a separate one of differently oriented antennas and determines which antenna received the strongest signal. The message signal from the terminal station is then received via the antenna of the transceiver having received the strongest signal and also sends its response message signal on that antenna during a separate time slot of a frame period.

摘要翻译： 本发明涉及一种便携式收发器和远程终端站，每个使用具有不同极化传输能力的至少两个天线，用于自适应重传技术。 在本自适应重传技术中，终端站在时分序列的帧周期的至少两个时隙中使用在紧邻的前一帧周期中从收发机接收最强信号的天线发送相同的前同步码信号，随后是二进制 消息信号使用相同的天线。 收发器经由不同定向天线中的单独的一个从终端站接收每个前导码传输，并确定哪个天线接收到最强的信号。 来自终端站的消息信号然后经收到最强信号的收发信机的天线接收，并在帧周期的单独时隙内在该天线上发送其响应消息信号。

公开(公告)号：US20130107928A1

公开(公告)日：2013-05-02

申请号：US13666820

申请日：2012-11-01

申请人： Donald C. Cox ,  Thomas G. McGiffen

发明人： Donald C. Cox ,  Thomas G. McGiffen

IPC分类号： H04B17/00

CPC分类号： H04B17/309 ,  H04B17/373 ,  H04L1/0003 ,  H04L1/0006 ,  H04L1/0009 ,  H04L1/0019 ,  H04L1/06 ,  H04L1/203

摘要： Methods and apparatus, including computer program products, are provided performance prediction. In one aspect there is provided a method. The method may include receiving information including one or more of a set of weights, a set of events, and a channel estimate, wherein at least one of the set of weights and the set of events are determined based on a optimization; and determining a transmitter configuration by performing at least one of: applying the set of weights to a set of pair wise error probabilities to determine a set of predicted bit error rates, and applying the set of events to the set of pair wise error probabilities to determine a set of predicted packet error rates. Related apparatus, systems, methods, and articles are also described.

摘要翻译： 方法和装置，包括计算机程序产品，都提供了性能预测。 在一个方面，提供了一种方法。 该方法可以包括接收包括一组权重，一组事件和信道估计中的一个或多个的信息，其中基于优化确定权重集和事件集合中的至少一个; 以及通过执行以下中的至少一个来确定发射机配置：将所述权重集合应用于一组成对的误差概率，以确定一组预测的比特误码率，以及将所述一组事件应用于所述一对成对的误差概率，以 确定一组预测的分组错误率。 还描述了相关装置，系统，方法和制品。

公开(公告)号：US06895248B1

公开(公告)日：2005-05-17

申请号：US09324367

申请日：1999-06-02

申请人： Bora A. Akyol ,  Donald C. Cox

发明人： Bora A. Akyol ,  Donald C. Cox

IPC分类号： H04L12/28 ,  H04L12/56 ,  H04Q7/20

CPC分类号： H04W72/0446 ,  H04L12/5601 ,  H04L2012/5632 ,  H04W28/14 ,  H04W28/26 ,  H04W72/0413 ,  H04W74/00 ,  H04W74/04 ,  Y10S370/905

摘要： A resource allocation method for use in a wireless ATM network comprises receiving on a wireless signaling channel a request for access to a shared frequency-time sliced wireless medium. A channel matrix is then searched for a set of available frequency-time slots. The channel matrix represents a time frame within the shared frequency-time sliced wireless medium, and is used to keep track of resource allocation in the time-frequency sliced medium. The set of available time-slots is then allocated if the allocation does not violate a frequency switching constraint, and if the set of available frequency-time slots contains a number of slots no smaller than a requested number of slots. In a preferred embodiment of the invention, the searching step uses a greedy resource allocation strategy to search a channel-chunk matrix comprising a list of contiguous chunks of available time slots in each frequency of the shared frequency-time sliced wireless medium. The greedy resource allocation strategy comprises the following successive allocation steps: searching for a single contiguous set of available time slots in a single frequency, where the size of the set of available slots is equal to the requested size [60]; searching for a single contiguous set of available time slots in a single frequency, where the size of the set of available slots is greater than the requested size [64]; searching for separate chunks of available time slots in a single frequency [66]; and searching for separate chunks of available time slots in multiple frequencies [68]. Each allocation step comprises checking whether the allocation violates a frequency switching constraint.

摘要翻译： 一种在无线ATM网络中使用的资源分配方法包括在无线信令信道上接收对共享的时分片式无线介质的访问请求。 然后，搜索一组可用频率时隙的信道矩阵。 信道矩阵表示共享时间分片无线介质内的时间帧，用于跟踪时间频率分片介质中的资源分配。 然后如果分配不违反频率切换约束，则分配可用时隙的集合，并且如果可用频率时隙的集合包含不少于所请求的时隙数量的时隙数量。 在本发明的优选实施例中，搜索步骤使用贪心资源分配策略来搜索包含共享时分片无线介质的每个频率中可用时隙的连续块的列表的信道块矩阵。 贪心资源分配策略包括以下连续分配步骤：在单个频率中搜索可用时隙的单个连续集合，其中可用时隙集合的大小等于所请求的大小[60]; 在单个频率中搜索单个连续的可用时隙集合，其中所述可用时隙集合的大小大于所请求的大小[64]; 在单个频率中搜索单独的可用时隙块[66]; 并在多个频率中搜索单独的可用时隙块[68]。 每个分配步骤包括检查分配是否违反频率切换约束。

公开(公告)号：US06583679B1

公开(公告)日：2003-06-24

申请号：US09893917

申请日：2001-06-28

申请人： Donald C. Cox ,  Mehdi F. Soltan ,  Thomas H. Lee

发明人： Donald C. Cox ,  Mehdi F. Soltan ,  Thomas H. Lee

IPC分类号： H03C100

CPC分类号： H03F1/0222 ,  H03F2200/331

摘要： An inexpensive method and means for generating high power envelope-modulated radio frequency signals is disclosed. Embodiments provide EER amplification and separate modulation of information encoded as phase angle and as amplitude. An envelope modulated signal generation apparatus comprising a source of carrier signal, a source of a binary data stream, a pulse deletion logic and a current switch is disclosed.

摘要翻译： 公开了一种用于产生高功率包络调制射频信号的廉价方法和装置。 实施例提供EER放大和编码为相位角和作为振幅的信息的单独调制。 公开了一种包括载波信号源，二进制数据流源，脉冲删除逻辑和电流开关的包络调制信号发生装置。

公开(公告)号：US06240291B1

公开(公告)日：2001-05-29

申请号：US09392975

申请日：1999-09-09

申请人： Ravi Narasimhan ,  Donald C. Cox

发明人： Ravi Narasimhan ,  Donald C. Cox

IPC分类号： H04Q720

CPC分类号： H04W36/30

摘要： A handoff technique for wireless communication systems uses pattern recognition of signal strength data to anticipate handoffs and reduce the total number of handoffs in the system. A criterion for system performance is used in determining the necessity for handoff. A window of signal samples from nearby base stations constitutes a pattern vector which is classified using a probabilistic neural network or other learning machine. The use of averaged signals and the sequencing of classes allow for a small number of training vectors for the pattern classifier. Substantially increased performance requires only one training vector per class. Simulation results indicate that, for a given probability of failure, the pattern recognition based handoff technique yields fewer handoffs than the conventional hysteresis rule.

摘要翻译： 无线通信系统的切换技术使用信号强度数据的模式识别来预测切换并减少系统中的切换总数。 系统性能的标准用于确定切换的必要性。 来自附近基站的信号样本窗构成使用概率神经网络或其他学习机分类的模式向量。 使用平均信号和类的排序允许用于模式分类器的少量训练向量。 基本上增加的性能每类只需要一个训练矢量。 仿真结果表明，对于给定的故障概率，基于模式识别的切换技术比传统的滞后规则产生更少的切换。