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公开(公告)号：US20100061484A1
公开(公告)日：2010-03-11
申请号：US12621335
申请日：2009-11-18
IPC分类号： H04L27/00
CPC分类号： H04L27/2601 , H04L1/0618
摘要： A MIMO OFDM system includes a plurality of space-time encoders for encoding respective data blocks with independent space-time codes. The transformed data block signals are transmitted by a plurality of transmit antennas and received by a plurality of receive antennas. The received data is pre-whitened prior to maximum likelihood detection. In one embodiment, successive interference cancellation can be sued to improve system performance. Channel parameter estimation can be enhanced by weighting the channel impulse response estimates based upon a deviation from average.
摘要翻译： MIMO OFDM系统包括用于对具有独立时空码的各个数据块进行编码的多个时空编码器。 经变换的数据块信号由多个发射天线发射并由多个接收天线接收。 接收的数据在最大似然检测之前被预先白化。 在一个实施例中，可以起诉连续的干扰消除以改善系统性能。 可以通过基于偏离平均值的信道脉冲响应估计来加权信道参数估计。
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公开(公告)号：US20090135756A1
公开(公告)日：2009-05-28
申请号：US12321555
申请日：2009-01-22
CPC分类号： H04W72/005 , H04B7/18523 , H04H20/67 , H04L5/023 , H04W52/0206 , H04W52/0216 , H04W72/0446 , H04W84/042 , Y02D70/164 , Y02D70/26 , Y02D70/446
摘要： An efficient method for providing both dedicated and simulcast services over a common wireless infrastructure is described. The services can be available to a single terminal as well as to a multiplicity of terminals simultaneously. The method uses time division multiplexing and orthogonal frequency division multiple access for simulcasting information and transmitting dedicated message information from a plurality of base stations forming a cellular pattern over the same wireless frequency channel. The method comprises the steps of constructing frames for transmission by the plurality of base stations comprising control information, simulcast information and dedicated message information within predetermined time slots of the frames and allocating the simulcast information and the dedicated message information to time slots of the same frame predetermined by the control information of the frame. The underlying modulation technology used is OFDM and thereby the channel delay-dispersion is minimized.
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43.发明授权Method and apparatus for implementing measurement based dynamic frequency hopping in wireless communication systems 有权用于在无线通信系统中实现基于测量的动态跳频的方法和装置公开(公告)号：US06826409B2
公开(公告)日：2004-11-30
申请号：US10366379
申请日：2003-02-14
IPC分类号： H04B1500
CPC分类号： H04B1/715 , H04B2001/7154 , H04L5/023
摘要： Proposed is a method for reducing interference in a frequency hopping wireless communications system. In one embodiment of the present invention, a base station and a terminal station each using an orthogonal frequency division multiplexing (OFDM) technique to simultaneously measure an interference level for each system frequency and to enable high speed frequency hop pattern changes which can follow changes in desired and interfering signal levels due to changes in co-channel interference or shadow fading. The terminal station interference level measurement values are then transmitted to the base station. Next, the base station identifies each frequency hop pattern currently in use by each terminal station communicating with that base station. The base station then uses both the base station interference level measurements and the terminal station interference level measurements to identify each frequency hop pattern in which at least one of the current system frequencies should be replaced with a system frequency having a lower interference level. Next, the base station replaces no more than a predetermined number of the current system frequencies within the identified frequency hop pattern(s). The above steps are executed at each base station within the system while ensuring that nearby interfering base stations do not replace frequencies at the same time.
摘要翻译： 提出了一种减少跳频无线通信系统干扰的方法。 在本发明的一个实施例中，一个基站和一个终端站，每个基站和终端站都使用正交频分复用（OFDM）技术来同时测量每个系统频率的干扰电平，并实现能够跟随变化的高速跳频模式改变 由于同频道干扰或阴影衰落的变化而导致的期望和干扰信号电平。 然后将终端干扰电平测量值发送到基站。 接下来，基站识别与该基站通信的每个终端当前正在使用的每个频率跳频模式。 基站然后使用基站干扰电平测量和终端干扰电平测量两者来识别其中至少一个当前系统频率应被具有较低干扰电平的系统频率替代的每个频率跳频模式。 接下来，基站在所识别的频率跳频模式中替换不超过预定数量的当前系统频率。 上述步骤在系统内的每个基站执行，同时确保附近的干扰基站不同时替换频率。
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公开(公告)号：US06795392B1
公开(公告)日：2004-09-21
申请号：US09535945
申请日：2000-03-27
申请人： Ye Li , Nelson Ray Sollenberger
发明人： Ye Li , Nelson Ray Sollenberger
IPC分类号： H04J1100
CPC分类号： H04L27/2647 , H04L5/023 , H04L25/0204 , H04L25/0242
摘要： An improved OFDM receiver is realized by employing a simplified delay function for the transmissions channel. The simplified delay function yields a simplified frequency-domain correlation that is applied to develop an Eigen matrix U that is used in developing estimates of the channels. Those channel estimates are used in the receiver to develop the output signals.
摘要翻译： 通过对传输信道采用简化的延迟函数来实现改进的OFDM接收机。 简化的延迟函数产生一个简化的频域相关性，用于开发用于开发信道估计的特征矩阵U。 在接收机中使用这些信道估计来开发输出信号。
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公开(公告)号：US06754506B2
公开(公告)日：2004-06-22
申请号：US09784901
申请日：2001-02-16
申请人： Li Fung Chang , Kapil K. Chawla , Justin Chi-I Chuang , Zoran Kostic , Xiaoxin Qiu , Nelson Ray Sollenberger , Shailender B. Timiri
发明人： Li Fung Chang , Kapil K. Chawla , Justin Chi-I Chuang , Zoran Kostic , Xiaoxin Qiu , Nelson Ray Sollenberger , Shailender B. Timiri
IPC分类号： H04Q720
CPC分类号： H04W52/12 , H04W52/20 , H04W52/225 , H04W52/241 , H04W52/36
摘要： A TDMA wireless communication system adjusts the power control target and transmission power based upon link quality to enhance voice capacity. The power can be adjusted in response to the average SNIR and number of decoding errors in a link quality reporting period. The power control target can be increased and decreased in discrete intervals after evaluating the number of decoding errors in the reporting period. The transmission power can be adjusted towards the new power control target based upon the average SNIR.
摘要翻译： TDMA无线通信系统基于链路质量调整功率控制目标和传输功率，以增强语音容量。 可以响应于链路质量报告周期中的平均SNIR和解码错误的数量来调整功率。 在评估报告期间的解码错误数量之后，可以以离散间隔增加和减少功率控制目标。 可以基于平均SNIR向新的功率控制目标调整发射功率。
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46.发明授权Method and apparatus for enhancing communication reception at a wireless communication terminal 失效一种用于增强无线通信终端的通信接收的方法和装置
公开(公告)号：US6131016A
公开(公告)日：2000-10-10
申请号：US920138
申请日：1997-08-27
CPC分类号： H04L1/06 , H04B7/061 , H04B7/0626 , H04L5/0023 , H04L5/0051 , H04L5/006 , H04L5/0091 , H04L2025/03414 , H04L2025/03426 , H04L2025/03802 , H04L25/0228 , H04L25/03343
摘要： A system provides transmit diversity with feedback to enhance the reception of communication signals at a wireless communication terminal. Multiple antennae are provided at the base station. The multiple antennae transmit multi-carrier information signals such as OFDM including pilot tones. The wireless communication terminal receives the pilot tones and performs processing on those tones to detect the relationship between the information signals transmitted from the various antennae of the base station. A feedback signal, based on the comparison of the pilot tones communicates back to the base station information about the channels of the respective transmit antennae to the terminals. The base station modifies the transmission processing associated with the various transmit antennae based upon the feedback signal. The modified processing improves the reception of the information signals at the wireless communication terminal.
摘要翻译： 系统提供具有反馈的发射分集以增强无线通信终端处的通信信号的接收。 在基站提供多个天线。 多个天线发射诸如OFDM的多载波信息信号，包括导频音调。 无线通信终端接收导频音，并对这些音调进行处理，以检测从基站的各个天线发送的信息信号之间的关系。 基于导频音的比较的反馈信号将关于各终端的各个发射天线的信道的基站信息通信回来。 基站根据反馈信号修改与各种发送天线相关联的发送处理。 经修改的处理改善了无线通信终端处的信息信号的接收。
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47.发明授权System and method for dynamically assigning channels for wireless packet communications 失效用于动态分配无线分组通信信道的系统和方法
公开(公告)号：US6052594A
公开(公告)日：2000-04-18
申请号：US846712
申请日：1997-04-30
IPC分类号： H04L12/28 , H04L12/56 , H04W24/00 , H04W68/00 , H04W72/06 , H04W72/08 , H04W72/10 , H04W74/00 , H04Q7/20
CPC分类号： H04W72/085 , H04L5/0044 , H04L5/0048 , H04L5/0064 , H04W68/00 , H04W72/06 , H04W72/10
摘要： A method and system for controlling media access in which a paging message is transmitted from a base station to a wireless station when a data packet is received for downlink transmission to the wireless station. The base station is one of a plurality of base stations and the wireless station is associated with the base station. In response to the paging message, a level of each of a plurality of pilot frequency signals is detected at the wireless station. Each pilot frequency corresponds to a downlink traffic channel and is transmitted by base stations to which the downlink traffic channel is assigned. The wireless station generates a list of preferred traffic channels based on a priority order of traffic channels and on detected levels of the pilot frequency signals, and transmits the list to the associated base station. A downlink traffic channel is assigned for downlink transmitting the received data packet to the wireless station based on the list of preferred traffic channels and updates a channel priority order list at the base station.
摘要翻译： 一种用于控制媒体接入的方法和系统，其中当接收到用于下行链路传输到无线站的数据分组时，寻呼消息从基站发送到无线站。 基站是多个基站之一，无线站与基站相关联。 响应于寻呼消息，在无线站处检测多个导频信号中的每一个的电平。 每个导频对应于下行链路业务信道，并由下行业务信道被分配到的基站发送。 无线站基于业务信道的优先级顺序和导频信号的检测级别生成优选业务信道的列表，并将该列表发送到相关联的基站。 下行链路业务信道被分配用于基于优选业务信道的列表将接收到的数据分组发送到无线站的下行链路业务信道，并且更新基站处的信道优先级顺序列表。
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公开(公告)号：US5946351A
公开(公告)日：1999-08-31
申请号：US777335
申请日：1996-12-27
CPC分类号： H04L25/03057 , H04L7/04
摘要： A decision feedback equalizer receiver that assigns a number F of feedforward filter taps and optimizes digital receiver performance in multipath channel environments, where F is an integer less than a memory length of a radio channel. The feedforward filter taps are assigned to delay times corresponding to an optimum burst timing parameter delay time, d(0), and to F-1 time delays based on "tap SNR indices." For an Uncorrelated Inter-Symbol-Interference (UISI) case, the F-1 time delays are the first F-1 rank ordered time delays are selected as the feedforward tap delay times. For a general case, a combination of the UISI case and an analytical two cluster case is obtained by selecting the first F-2 rank ordered time delays and a 2D time delay, where D is the delay time corresponding to the largest estimated tap SNR index.
摘要翻译： 分配前馈滤波器抽头数量F的判决反馈均衡器接收器，并且在多径信道环境中优化数字接收器性能，其中F是小于无线电信道的存储器长度的整数。 前馈滤波器抽头被分配给对应于最佳突发定时参数延迟时间d（0）的延迟时间，并分配给基于“抽头SNR指数”的F-1时间延迟。 对于不相关的符号间干扰（UISI）情况，F-1时间延迟是第一个F-1等级有序时间延迟作为前馈抽头延迟时间。 对于一般情况，通过选择第一F-2秩有序时间延迟和2D时间延迟来获得UISI情况和分析两个群集情况的组合，其中D是对应于最大估计抽头SNR指数的延迟时间 。
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公开(公告)号：US09426009B2
公开(公告)日：2016-08-23
申请号：US13296610
申请日：2011-11-15
CPC分类号： H04L27/2601 , H04L1/0618
摘要： A MIMO OFDM system includes a plurality of space-time encoders for encoding respective data blocks with independent space-time codes. The transformed data block signals are transmitted by a plurality of transmit antennas and received by a plurality of receive antennas. The received data is pre-whitened prior to maximum likelihood detection. In one embodiment, successive interference cancellation can be sued to improve system performance. Channel parameter estimation can be enhanced by weighting the channel impulse response estimates based upon a deviation from average.
摘要翻译： MIMO OFDM系统包括用于对具有独立时空码的各个数据块进行编码的多个时空编码器。 经变换的数据块信号由多个发射天线发射并由多个接收天线接收。 接收的数据在最大似然检测之前被预先白化。 在一个实施例中，可以起诉连续的干扰消除以改善系统性能。 可以通过基于偏离平均值的信道脉冲响应估计来加权信道参数估计。
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公开(公告)号：US08571002B2
公开(公告)日：2013-10-29
申请号：US12804099
申请日：2010-07-14
IPC分类号： H04J3/00
CPC分类号： H04W72/005 , H04B7/18523 , H04H20/67 , H04L5/023 , H04W52/0206 , H04W52/0216 , H04W72/0446 , H04W84/042 , Y02D70/164 , Y02D70/26 , Y02D70/446
摘要： An efficient method for providing both dedicated and simulcast services over a common wireless infrastructure is described. The services can be available to a single terminal as well as to a multiplicity of terminals simultaneously. The method uses time division multiplexing and orthogonal frequency division multiple access for simulcasting information and transmitting dedicated message information from a plurality of base stations forming a cellular pattern over the same wireless frequency channel. The method comprises the steps of constructing frames for transmission by the plurality of base stations comprising control information, simulcast information and dedicated message information within predetermined time slots of the frames and allocating the simulcast information and the dedicated message information to time slots of the same frame predetermined by the control information of the frame. The underlying modulation technology used is OFDM and thereby the channel delay-dispersion is minimized.
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