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    Method and apparatus for adaptive rate selection in a communication system
    31.
    发明授权
    Method and apparatus for adaptive rate selection in a communication system 失效
    通信系统中自适应速率选择的方法和装置

    公开(公告)号：US06760313B1

    公开(公告)日：2004-07-06

    申请号：US09597516

    申请日：2000-06-19

    申请人： Nagabhushana T. Sindhushayana ,  Eduardo A. S. Esteves ,  Rashid A. Attar ,  Qiang Wu

    发明人： Nagabhushana T. Sindhushayana ,  Eduardo A. S. Esteves ,  Rashid A. Attar ,  Qiang Wu

    IPC分类号： G01R3108

    CPC分类号： H04L1/0002

    摘要： A method and an apparatus for adaptive data rate selection in a high data rate (HDR) communication system are disclosed. An exemplary HDR communication system defines a set of data rates, at which an access point (AP) may transmit data packets to an access terminal (AT). The transmission data rate is selected to maintain target packet error rate (PER). Each AT monitors signal quality metric of signals received from APs. An AT receiving forward link signals from multiple ATs identifies the AT associated with the highest quality forward link signal. The AT then evaluates the rate at which a tail probability of error is greater than or equal to a target tail probability of error. The AT then generates a prediction of a first data rate at which the PER of packets received from the identified AP will not exceed the target PER, and a prediction of a second data rate at which the PER of packets received from the selected AP will exceed the target PER. The AT uses the values of the first and second data rates to predict probabilities of selecting the first and the second data rates such that a throughput of the HDR system is maximized and the target PER is achieved. The predicted probabilities are then utilized as biases for a method identifying whether the first data rate or the second data rate will be requested from the AP. The disclosed method and apparatus may be extended to the full set of available data rates.

    摘要翻译： 公开了一种在高数据速率（HDR）通信系统中进行自适应数据速率选择的方法和装置。 示例性HDR通信系统定义了一组数据速率，接入点（AP）可在该组数据速率上向接入终端（AT）发送数据分组。 选择传输数据速率以维持目标分组错误率（PER）。 每个AT监视从AP接收的信号的信号质量度量。 从多个AT接收前向链路信号的AT识别与最高质量的前向链路信号相关联的AT。 AT然后评估误差的概率大于或等于目标尾部误差概率的速率。 然后，AT产生对从所识​​别的AP接收的分组的PER不超过目标PER的第一数据速率的预测，以及从所选择的AP接收的分组的PER将超过的第二数据速率的预测 目标PER。 AT使用第一和第二数据速率的值来预测选择第一和第二数据速率的概率，使得HDR系统的吞吐量最大化并且实现目标PER。 然后，将预测概率用作用于识别从AP请求第一数据速率或第二数据速率的方法的偏差。 所公开的方法和装置可以扩展到全部可用数据速率。

    Efficient iterative decoding
    32.
    发明授权
    Efficient iterative decoding 有权
    高效迭代解码

    公开(公告)号：US06678857B2

    公开(公告)日：2004-01-13

    申请号：US09887285

    申请日：2001-06-20

    申请人： Nagabhushana T. Sindhushayana ,  Jeremy M. Stein

    发明人： Nagabhushana T. Sindhushayana ,  Jeremy M. Stein

    IPC分类号： H03M1329

    CPC分类号： H03M13/2975 ,  H03M13/29 ,  H04L1/0051

    摘要： Apparatus for iterative decoding of a sequence of signal packets coded in accordance with a multi-component coding scheme. The apparatus includes a plurality of decoders, each of which performs a respective different decoding method on one of the signal packets, such that the plurality of decoders operate substantially concurrently.

    摘要翻译： 用于对根据多分量编码方案编码的信号分组序列进行迭代解码的装置。 该装置包括多个解码器，每个解码器在信号分组中的一个上执行相应的不同的解码方法，使得多个解码器基本同时地进行操作。

    System and method for providing an accurate estimation of received signal interference for use in wireless communications systems
    33.
    发明授权
    System and method for providing an accurate estimation of received signal interference for use in wireless communications systems 有权
    提供用于无线通信系统的接收信号干扰的精确估计的系统和方法

    公开(公告)号：US06661832B1

    公开(公告)日：2003-12-09

    申请号：US09310053

    申请日：1999-05-11

    申请人： Nagabhushana T. Sindhushayana ,  Eduardo A. S. Esteves

    发明人： Nagabhushana T. Sindhushayana ,  Eduardo A. S. Esteves

    IPC分类号： H04B1707

    CPC分类号： H04L27/38 ,  H04B1/712 ,  H04B17/336 ,  H04L25/067 ,  H04L27/34

    摘要： A system for providing an accurate interference value signal received over a channel and transmitted by an external transceiver. The system includes a first receiver section for receiving the signal, which has a desired signal component and an interference component. A signal extracting circuit extracts an estimate of the desired signal component from the received signal. A noise estimation circuit provides the accurate interference value based on the estimate of the desired signal component and the received signal. A look-up table transforms the accurate noise and/or interference value to a normalization factor. A carrier signal-to interference ratio circuit employs the normalization factor and the received signal to compute an accurate carrier signal-to-interference ratio estimate. Path-combining circuitry generates optimal path-combining weights based on the received signal and the normalization factor. In the illustrative embodiment, the system further includes a circuit for employing the accurate interference value to compute a carrier signal-to-interference ratio. An optimal path-combining circuit computes optimal path-combining weights for multiple signal paths comprising the signal using the accurate interference value and provides optimally combined signal paths in response thereto. A log-likelihood ratio circuit computes a log-likelihood value based on the carrier signal-to-interference ratio and the optimally combined signal paths. A decoder decodes the received signal using the log-likelihood value. An additional circuit generates a rate and/or power control message and transmits the rate and/or power control message to the external transceiver.

    摘要翻译： 一种用于提供通过信道接收并由外部收发器发射的精确干扰值信号的系统。 该系统包括用于接收信号的第一接收器部分，其具有期望的信号分量和干扰分量。 信号提取电路从接收信号中提取所需信号分量的估计。 噪声估计电路基于期望信号分量和接收信号的估计提供精确的干扰值。 查找表将精确的噪声和/或干扰值转换为归一化因子。 载波信号与干扰比电路采用归一化因子和接收信号来计算准确的载波信号与干扰比估计。 路径组合电路基于接收信号和归一化因子产生最佳路径组合权重。 在说明性实施例中，系统还包括用于采用精确干扰值来计算载波信号干扰比的电路。 最佳路径组合电路使用精确的干扰值来计算包括信号的多个信号路径的最佳路径组合权重，并且响应于此提供最佳组合的信号路径。 对数似然比电路基于载波信号干扰比和最佳组合信号路径来计算对数似然值。 解码器使用对数似然值来解码接收到的信号。 附加电路产生速率和/或功率控制消息，并将速率和/或功率控制消息发送到外部收发器。

    Method and apparatus for variable and fixed forward link rate control in a mobile radio communication system
    34.
    发明授权
    Method and apparatus for variable and fixed forward link rate control in a mobile radio communication system 有权
    移动无线电通信系统中可变和固定的前向链路速率控制的方法和装置

    公开(公告)号：US06560211B2

    公开(公告)日：2003-05-06

    申请号：US09748319

    申请日：2000-12-22

    申请人： Eduardo A. S. Esteves ,  Rajesh K. Pankaj ,  Peter J. Black ,  Matthew S. Grob ,  Nagabhushana T. Sindhushayana

    发明人： Eduardo A. S. Esteves ,  Rajesh K. Pankaj ,  Peter J. Black ,  Matthew S. Grob ,  Nagabhushana T. Sindhushayana

    IPC分类号： H04Q700

    CPC分类号： H04W28/22 ,  H04L1/0002 ,  H04L1/0036 ,  H04L2001/0092 ,  H04W36/18

    摘要： A method and apparatus for controlling a data rate associated with the transmission of information from a base station to a mobile station in a mobile radio communication system. The mobile station alternately receives information from a base station either in a variable rate mode or a fixed rate mode. The transmission rate from a base station in the variable rate mode varies between successive data transmit intervals, and the transmission rate from a base station in the fixed rate mode remains fixed between successive data transmit intervals. Data is transmitted from a first base station to the mobile station in the variable rate mode until the first base station is unable to receive variable data rate control information from the mobile station.

    摘要翻译： 一种用于在移动无线电通信系统中控制与从基站到移动台的信息传输相关联的数据速率的方法和装置。 移动台以可变速率模式或固定速率模式从基站交替地接收信息。 来自基站的可变速率模式的传输速率在连续的数据发送间隔之间变化，并且来自固定速率模式的基站的传输速率在连续的数据发送间隔之间保持固定。 数据以可变速率模式从第一基站发送到移动台，直到第一基站不能从移动台接收可变数据速率控制信息。

    Method for assigning optimal packet lengths in a variable rate communication system
    35.
    发明授权
    Method for assigning optimal packet lengths in a variable rate communication system 失效
    在可变速率通信系统中分配最佳分组长度的方法

    公开(公告)号：US6064678A

    公开(公告)日：2000-05-16

    申请号：US965705

    申请日：1997-11-07

    申请人： Nagabhushana T. Sindhushayana ,  Roberto Padovani

    发明人： Nagabhushana T. Sindhushayana ,  Roberto Padovani

    IPC分类号： H04L1/00 ,  H04L29/08 ,  H04W28/18 ,  H04J3/22

    CPC分类号： H04W28/18 ,  H04L1/0007 ,  H04L1/0018

    摘要： A method for assigning optimal packet lengths in a variable rate communication system capable of data transmission at one of a plurality of data rates. The packet lengths for the data rates are selected such that the maximum throughput rate is achieved while conforming to a fairness criteria. The fairness criteria can be achieved by restricting the packet length assigned to each data rate to a range of value, or L.sub.i.sup.min .ltoreq.L.sub.i .ltoreq.L.sub.i.sup.max. The packet lengths for all data rates are first initialized to the maximum packet lengths for those data rates. Then, for each data rate, a determination is made whether another packet length assignment would result in improved throughput rate. If the answer is yes, the packet length for this data rate is reassigned and the throughput rate with the updated packet length assignments is recomputed. The process is repeated for each data rate until all data rates have been considered. The throughput rate can be calculated using a probabilistic model or a deterministic model.

    摘要翻译： 一种用于在能够以多个数据速率之一进行数据传输的可变速率通信系统中分配最佳分组长度的方法。 选择数据速率的分组长度，使得在符合公平标准的同时实现最大吞吐速率。 公平性标准可以通过将分配给每个数据速率的分组长度限制在一定范围内来实现，或者使用Limin

    Soft decision output decoder for decoding convolutionally encoded codewords
    36.
    发明授权
    Soft decision output decoder for decoding convolutionally encoded codewords 失效
    用于解码卷积编码码字的软判决输出解码器

    公开(公告)号：US5933462A

    公开(公告)日：1999-08-03

    申请号：US743688

    申请日：1996-11-06

    申请人： Andrew J. Viterbi ,  Nagabhushana T. Sindhushayana

    发明人： Andrew J. Viterbi ,  Nagabhushana T. Sindhushayana

    IPC分类号： H03M13/00 ,  H03M13/39 ,  H03M13/41 ,  H04L1/00 ,  H03D1/00 ,  H04L27/06

    CPC分类号： H03M13/3911 ,  H03M13/2957 ,  H03M13/3905 ,  H03M13/3972 ,  H03M13/41 ,  H04L1/005 ,  H04L1/0054 ,  H04L1/0055 ,  H04L1/006

    摘要： A soft decision output decoder and decoding method. The decoder decodes a sequence of signals output by an encoder and transmitted over a channel. The soft decision output decoder includes a first "generalized" Viterbi decoder for decoding the sequence of signals received over the channel during a forward iteration through a trellis representing the encoder output having a block length T. The first "generalized" Viterbi decoder begins at an initial state t.sub.0 and provides a plurality of forward iteration state metrics .alpha. for each state at each time interval over a window of length 2L, where L is on the order of a few constraint lengths and 2L is less than a block length T. A second "generalized" Viterbi decoder decodes the sequence of signals received over the channel during a backward iteration through the trellis. The second decoder starts at a second time t2L and provides a plurality of backward iteration state metrics .beta. for each state at each time interval. A processor then performs a dual maxima computation at each state using the forward state metric, the backward state metric and the branch metric for same to provide a measure of the likelihood that a particular sequence of data was transmitted by the encoder. The processor computes a log of the likelihood ratio using the forward and backward state metrics and the branch metrics for a selected state. This is achieved by first computing a max function as an approximation of the measure of the likelihood that a particular sequence of data was transmitted by the encoder. By performing forward and backward Viterbi decoding with dual maxima computations at each node within a window moved over the trellis, the inventive decoder provides the performance benefits associated with a LOG-MAP decoder while avoiding the excessive memory requirements of same.

    摘要翻译： 软判决输出解码器和解码方法。 解码器解码由编码器输出并通过信道传输的信号序列。 软判决输出解码器包括第一“广义”维特比解码器，用于在通过表示具有块长度T的编码器输出的网格的前向迭代期间解码通过信道接收的信号序列。第一“广义”维特比解码器以 初始状态t0，并且在长度为2L的窗口上的每个时间间隔处为每个状态提供多个前向迭代状态度量α，其中L在几个约束长度的数量级上，2L小于块长度T.第二 “广义的”维特比解码器在通过网格的向后迭代期间解码在信道上接收的信号的序列。 第二解码器在第二时间t2L开始，并且在每个时间间隔为每个状态提供多个反向迭代状态度量β。 然后，处理器在每个状态下使用正向状态度量，后向状态度量和相同的分支量度来执行双最大值计算，以提供由编码器发送特定数据序列的可能性的度量。 处理器使用前向和后向状态度量以及所选状态的分支度量来计算似然比的对数。 这是通过首先计算最大函数作为对编码器传送特定数据序列的可能性的度量的近似来实现的。 通过在通过网格移动的窗口内的每个节点处执行双向最大计算的前向和后向维特比解码，本发明的解码器提供与LOG-MAP解码器相关联的性能优点，同时避免了相同的过多的存储器要求。

    Method and an apparatus for a quick retransmission of signals in a communication system
    40.
    发明授权
    Method and an apparatus for a quick retransmission of signals in a communication system 有权
    用于在通信系统中快速重传信号的方法和装置

    公开(公告)号：US07613978B2

    公开(公告)日：2009-11-03

    申请号：US11518329

    申请日：2006-09-07

    申请人： Ahmad Jalali ,  Eduardo A.S. Esteves ,  Nagabhushana T. Sindhushayana ,  Peter J. Black ,  Rashid A. Attar

    发明人： Ahmad Jalali ,  Eduardo A.S. Esteves ,  Nagabhushana T. Sindhushayana ,  Peter J. Black ,  Rashid A. Attar

    IPC分类号： G08C25/02 ,  G06F11/00

    CPC分类号： H04L1/1887 ,  H04L1/1692 ,  H04L1/1809 ,  H04L1/1848 ,  H04L1/1877 ,  H04L1/188

    摘要： A method and an apparatus for quick retransmission of signals in a communication system are disclosed. A transmitting terminal, e.g., a base station, transmits signals in a form of packets to a receiving terminal, e.g., a subscriber station. The receiving terminal determines if the packet was intended for the receiving terminal, and if so, the receiving terminal demodulates the packet. The receiving terminal then computes a quality metric of the packet, and compares the computed quality metric with a quality metric contained in the packet. If the quality metrics match, the packet is declared correctly received, and is forwarded for further processing. If the quality metrics fail to match, the receiving terminal sends a request for retransmission of the packet. The transmitting terminal determines which packet needs to be retransmitted based on the request for retransmission. The transmitting terminal then schedules the packet for retransmission.

    摘要翻译： 公开了一种在通信系统中快速重发信号的方法和装置。 发送终端（例如基站）以分组的形式向接收终端（例如，用户台）发送信号。 接收终端确定分组是否用于接收终端，如果是，则接收终端解调分组。 接收终端然后计算分组的质量度量，并将计算的质量度量与分组中包含的质量度量进行比较。 如果质量度量匹配，则报文被正确地接收，并被转发用于进一步的处理。 如果质量度量不匹配，则接收终端发送分组请求。 发送终端根据重传请求确定哪个分组需要重传。 然后，发送终端调度分组进行重传。