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11.发明授权Trellis coding technique to increase adjacent channel interference protection ratio in land mobile radio systems under peak power constraints 失效网格编码技术在峰值功率约束下增加陆地移动无线电系统中的相邻信道干扰保护比
公开(公告)号：US5311553A
公开(公告)日：1994-05-10
申请号：US975201
申请日：1992-06-15
CPC分类号： H03M13/256 , H03M13/00 , H03M13/25 , H04L27/186
摘要： An optimum communication system employs an encoder coupled to a mapper and two parallel branches, each branch having a transmit filter a digital-to-analog converter, a low pass filter and a modulator coupled in series. Both modulators are coupled to a summer which provides an rf signal to a transmit antenna. A second antenna is coupled to a first down converter, an IF filter, a second down converter, an analog-to-digital converter and a decoder. The encoder is optimized by choosing a desired minimum Euclidean distance between symbols multiplied by the average to peak transmit power ratio (MPDR), an encoder alphabet and a number of constellation points. All possible encoder states and all possible input symbols are permutated to result in a plurality of encoder sets. The minimum distance between coded symbols and a P.sub.ib /P.sub.ab power ratio for each code set is determined. The encoder is adapted to output an encoder set U having a largest P.sub.ib /P.sub.ab power ratio having a large adjacent channel interference protection ratio. In an alternative embodiment, a minimum P.sub.ib /P.sub.ab power ratio (MPR) is chosen. The encoder is adapted to output an encoder set U having the largest minimum distance between coded symbols multiplied by the average to peak transmitted power ratio, that also has a P.sub.ib /P.sub.ab ratio that exceeds MPR.
摘要翻译： 最佳通信系统采用耦合到映射器和两个并行分支的编码器，每个分支具有发射滤波器，数模转换器，低通滤波器和串联耦合的调制器。 两个调制器耦合到向发射天线提供射频信号的夏季。 第二天线耦合到第一下变换器，IF滤波器，第二下变频器，模数转换器和解码器。 通过选择符号乘以平均与峰值发射功率比（MPDR），编码器字母和星座点数之间的期望的最小欧几里德距离来优化编码器。 所有可能的编码器状态和所有可能的输入符号被排列以产生多个编码器组。 确定每个代码集的编码符号与Pib / Pab功率比之间的最小距离。 编码器适于输出具有大的相邻信道干扰保护比的具有最大Pib / Pab功率比的编码器组U。 在替代实施例中，选择最小Pib / Pab功率比（MPR）。 编码器适于输出编码符号之间具有最大最小距离乘以平均值与峰值发射功率比的编码器组U，其也具有超过MPR的Pib / Pab比。
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12.发明授权Apparatus and method for selecting between a plurality of antennas utilized by a microcellular communications terminal for reception of a signal 失效用于在微蜂窝通信终端利用的用于接收信号的多个天线之间进行选择的装置和方法公开(公告)号：US06226507B1
公开(公告)日：2001-05-01
申请号：US09017829
申请日：1998-02-03
IPC分类号： H04B106
CPC分类号： H04B7/082 , H04B7/0842
摘要： An apparatus and method for selecting between a plurality of antennas utilized by a microcellular communications terminal for reception of a signal, wherein a gain imbalance exists between the antennas.
摘要翻译： 一种用于在微蜂窝通信终端利用的多个天线之间进行选择以接收信号的装置和方法，其中天线之间存在增益不平衡。
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公开(公告)号：US06493322B1
公开(公告)日：2002-12-10
申请号：US08840268
申请日：1997-04-14
IPC分类号： H04J314
CPC分类号： H04B7/18534
摘要： A diversity scheme for allowing a transmitter/receiver, such as a mobile unit in a mobile telecommunications system, to exchange communication signals with more than one control station, such as a base station or satellite. According to an exemplary embodiment of the diversity scheme, the mobile unit scans for the control channel of a second satellite during idle time slots while communicating with a first satellite during active time slots. Once the mobile unit detects a control channel from a second satellite, the mobile unit stores synchronization information and establishes a communication link with the second satellite if shadowing or other severe fading causes signal quality over a communication link established with a first satellite to fall below a threshold level. The diversity scheme also allows the mobile unit to communicate simultaneously with two satellites, using alternate TDMA frames.
摘要翻译： 用于允许诸如移动电信系统中的移动单元的发射机/接收机与诸如基站或卫星的多于一个控制站交换通信信号的分集方案。 根据分集方案的示例性实施例，移动单元在空闲时隙期间扫描第二卫星的控制信道，同时在活动时隙期间与第一卫星通信。 一旦移动单元检测到来自第二卫星的控制信道，则移动单元存储同步信息并与第二卫星建立通信链路，如果阴影或其他严重衰落导致通过与第一卫星建立的通信链路的信号质量降至低于 门限等级。 分集方案还允许移动单元使用备用TDMA帧同时与两颗卫星通信。
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14.发明授权Method and apparatus for multipath delay estimation in direct sequence spread spectrum communication systems 失效直接序列扩频通信系统中多径延迟估计的方法和装置公开(公告)号：US06839378B1
公开(公告)日：2005-01-04
申请号：US09005580
申请日：1998-01-12
IPC分类号： H04B1/711 , H04B1/709 , H04B1/7113 , H04B7/26 , H04B1/69
CPC分类号： H04B1/7113
摘要： Multipath delay estimation of a direct sequence spread spectrum (DS-SS) signal transmitted in a multipath fading channel is accomplished by measuring the envelope of the signal to determine a new delay estimate. Delay estimates are also obtained in ray strength order, by subtracting out the influence of the stronger rays on the weaker ones. This subtraction approach can be performed iteratively, allowing further refinement of the delay estimates. Delay estimates can also be determined by minimizing the mean square error (MSE) between a measured correlation function and a modeled correlation function. The minimum mean square error (MMSE) approach can performed iteratively, to further refine the delay estimates. Maximum likelihood (ML) delay estimates can also be obtained by exploiting side information regarding the transmit and receive pulse shapes.
摘要翻译： 在多径衰落信道中发送的直接序列扩频（DS-SS）信号的多路径延迟估计是通过测量信号的包络来确定新的延迟估计来实现的。 通过减去较强光线对较弱光线的影响，也可以通过光线强度顺序获得延迟估计。 可以迭代地执行该减法方法，从而进一步改进延迟估计。 延迟估计也可以通过最小化测量的相关函数和建模的相关函数之间的均方误差（MSE）来确定。 最小均方误差（MMSE）方法可以迭代地进行，以进一步改进延迟估计。 最大似然（ML）延迟估计也可以通过利用有关发射和接收脉冲形状的侧面信息来获得。
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公开(公告)号：US5661724A
公开(公告)日：1997-08-26
申请号：US574141
申请日：1995-12-18
CPC分类号： H04B7/18534
摘要： A diversity scheme for allowing a transmitter/receiver, such as a mobile unit in a mobile telecommunications system, to exchange communication signals with more than one control station, such as a base station or satellite. According to an exemplary embodiment of the diversity scheme, the mobile unit scans for the control channel of a second satellite during idle time slots while communicating with a first satellite during active time slots. Once the mobile unit detects a control channel from a second satellite, the mobile unit stores synchronization information and establishes a communication link with the second satellite if shadowing or other severe fading causes signal quality over a communication link established with a first satellite to fall below a threshold level. The diversity scheme also allows the mobile unit to communicate simultaneously with two satellites, using alternate TDMA frames.
摘要翻译： 用于允许诸如移动电信系统中的移动单元的发射机/接收机与诸如基站或卫星的多于一个控制站交换通信信号的分集方案。 根据分集方案的示例性实施例，移动单元在空闲时隙期间扫描第二卫星的控制信道，同时在活动时隙期间与第一卫星通信。 一旦移动单元检测到来自第二卫星的控制信道，则移动单元存储同步信息并与第二卫星建立通信链路，如果阴影或其他严重衰落导致通过与第一卫星建立的通信链路的信号质量降至低于 门限等级。 分集方案还允许移动单元使用备用TDMA帧同时与两颗卫星通信。
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16.发明授权
公开(公告)号：US5363407A
公开(公告)日：1994-11-08
申请号：US939747
申请日：1992-09-02
CPC分类号： H04B15/00 , H04B1/0475
摘要： A method of configuring an optimum communication system for communicating on adjacent frequency bands with minimal interference between adjacent channels comprises serially coupling a selected encoder to a mapper, a transmit filter, a low pass filter and a modulator, and constructing a receiver with a seriallycoupled receive filter and decoder. The transmit filter is optimized by choosing transmit filter coefficients d.sub.opt which maximize the inband to adjacent-band power. Transmitter coefficients d.sub.opt are obtained by solving an eigenvalue problem which takes into account the power spectrum of the encoder, mapper and receive filter. The optimum transmitter coefficients are then employed in the transmitter to shape the transmitted signal, increasing the adjacent channel interference protection ratio (ACIPR). In an alternative embodiment, further constraints are placed upon the system, such as reducing the combined impulse response of the transmit filter, low pass filter and the receive filter to zero at the beginning of subsequent symbol periods. The resulting system then exhibits an increased ACIPR along with a reduced intersymbol interference.
摘要翻译： 配置用于以相邻信道之间的最小干扰在相邻频带上通信的最佳通信系统的方法包括将所选择的编码器串行耦合到映射器，发射滤波器，低通滤波器和调制器，以及构造具有串联接收的接收机 滤波器和解码器。 通过选择将带内最大化为相邻带功率的发射滤波器系数dopt来优化发射滤波器。 通过求解考虑到编码器，映射器和接收滤波器的功率谱的特征值问题来获得发射机系数dopt。 然后在发射机中采用最佳发射机系数来对发射信号进行整形，增加相邻信道干扰保护比（ACIPR）。 在替代实施例中，进一步的约束被放置在系统上，诸如在随后的符号周期开始时将发射滤波器，低通滤波器和接收滤波器的组合脉冲响应减小到零。 所得到的系统随后表现出增加的ACIPR以及减少的符号间干扰。
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17.发明授权METHOD AND APPARATUS FOR COMMUNICATING AUXILLIARY INFORMATION AND LOCATION INFORMATION BETWEEN A CELLULAR TELEPHONE NETWORK AND A GLOBAL POSITIONING SYSTEM RECEIVER FOR REDUCING CODE SHIFT SEARCH TIME OF THE RECEIVER 有权用于通信蜂窝电话网络和全球定位系统接收器之间的辅助信息和位置信息的方法和装置，用于减少代码移位接收器的搜索时间公开(公告)号：US06415154B1
公开(公告)日：2002-07-02
申请号：US09167077
申请日：1998-10-06
IPC分类号： H04Q720
CPC分类号： G01S5/0036 , G01S19/25 , G01S19/37 , G01S2205/008
摘要： A method and apparatus for communicating auxiliary information between a cellular telephone network and a GPS receiver positioned within a mobile station and identifying the location of the mobile station. A dedicated channel between the mobile station and the network is assigned by the network and uplink timing between the mobile station and the network is adjusted. The network requests auxiliary information and also requests the GPS receiver to perform a GPS code shift search at a common reference time. Upon receiving the auxiliary information, the network transmits the auxiliary information to the GPS receiver which then performs the GPS code shift search. The GPS receiver incorporates a bank of correlators and accumulators to perform multiple parallel searches for various Doppler frequency shifts resulting from a moving GPS receiver. The mobile station subsequently transmits the location information to the cellular telephone network.
摘要翻译： 一种用于在蜂窝电话网络和位于移动站内的GPS接收机之间传送辅助信息并识别移动台的位置的方法和装置。 通过网络分配移动台与网络之间的专用信道，调整移动台与网络之间的上行定时。 网络请求辅助信息，并请求GPS接收机在公共参考时间执行GPS码移动搜索。 在接收到辅助信息时，网络将辅助信息发送到GPS接收机，然后执行GPS码移动搜索。 GPS接收机包含一组相关器和累加器，以对移动的GPS接收机产生的各种多普勒频移进行多次并行搜索。 移动台随后将位置信息发送到蜂窝电话网络。
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公开(公告)号：US6046990A
公开(公告)日：2000-04-04
申请号：US559692
申请日：1995-11-15
CPC分类号： H04L1/08 , H04B7/18567 , H04W68/00 , H04W68/02 , H04W88/185
摘要： A method and system for increasing the signal margin of a radiocommunication link to provide a short message service which is reliable, even under non-ideal conditions. According to the method, an increase in transmission power is used in combination with bit repetition to increase signal margin without complications in the mobile unit design, significant delay, or co-channel interference. Where a more significant increase in signal margin is desired, when a longer message is required, or for voice messages, the message may be stored and the mobile unit alerted of the message.
摘要翻译： 一种用于增加无线电通信链路的信号余量以提供即使在非理想条件下也是可靠的短消息服务的方法和系统。 根据该方法，与比特重复结合使用传输功率的增加以增加信号容限，而不会在移动单元设计，显着的延迟或同信道干扰中出现并发症。 在需要更大幅度地增加信号余量的情况下，当需要更长的消息或者对于语音消息时，可以存储消息并且移动单元提醒消息。
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公开(公告)号：US5822310A
公开(公告)日：1998-10-13
申请号：US579015
申请日：1995-12-27
CPC分类号： H04L1/08 , H04B7/18567
摘要： A method and system for increasing the signal margin of a radiocommunication link to provide a short message service which is reliable, even under non-ideal conditions. According to the method, short alphanumeric messages can be transmitted over the broadcast control channel of a digital radiocommunication link, or another communication channel consisting of one or more slots from successive frames in a TDMA communication link. An increase in transmission power is used in combination with repetition to increase effective signal margin without complications in the mobile unit design, significant delay, or co-channel interference. Where a more significant increase in signal margin is desired, when a longer message is required, or for voice messages, the message may be stored and the mobile unit alerted of the message.
摘要翻译： 一种用于增加无线电通信链路的信号余量以提供即使在非理想条件下也是可靠的短消息服务的方法和系统。 根据该方法，可以通过数字无线电通信链路的广播控制信道或由TDMA通信链路中的连续帧的一个或多个时隙组成的另一通信信道来传送短的字母数字消息。 传输功率的增加与重复结合使用以增加有效信号容限，而不会在移动单元设计，显着的延迟或同信道干扰中出现并发症。 在需要更大幅度地增加信号余量的情况下，当需要更长的消息或者对于语音消息时，可以存储消息并且移动单元提醒消息。
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20.发明授权Low complexity adaptive equalizer radio receiver employing reduced complexity branch metric calculation 失效低复杂度自适应均衡器无线电接收机采用降低复杂度的分支度量计算
公开(公告)号：US5488635A
公开(公告)日：1996-01-30
申请号：US143027
申请日：1993-10-29
CPC分类号： H04L25/03197 , H04L2025/03401 , H04L2025/03796
摘要： A low complexity adaptive equalizer for use in U.S. digital cellular radios demodulates .pi./4-shifted differentially encoded quadrature phase shift keyed (DQPSK) encoding in the presence of intersymbol interference (ISI) with reduced decoding complexity by employing an estimated received constellation which takes into account channel changes over time and ISI. The complexity is reduced by tracking a reduced number of estimated reference symbol constellation points and taking advantage of the geometry to estimate the remaining symbol constellation points. Branch metrics are also determined with a reduced number of computations.
摘要翻译： 用于美国数字蜂窝无线电的低复杂度自适应均衡器在存在码间干扰（ISI）的情况下，通过采用估计的接收星座来解调具有降低的解码复杂度的π/ 4位差分编码正交相移键控（DQPSK）编码 帐户频道随时间变化和ISI。 通过跟踪减少数量的估计参考符号星座点并利用几何来估计剩余的符号星座点来减少复杂度。 分支度量也用减少的计算数量确定。
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