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81.发明授权Methods for generating side information in the presence of time-selective fading 失效在存在时间选择性衰落的情况下生成副信息的方法公开(公告)号：US06581179B1
公开(公告)日：2003-06-17
申请号：US08669937
申请日：1996-06-25
申请人： Amer A. Hassan
发明人： Amer A. Hassan
IPC分类号： H03M1345
CPC分类号： H04B7/2643 , H03M13/1515 , H03M13/19 , H03M13/2906 , H03M13/3707 , H03M13/612 , H04L1/0045 , H04L1/0065
摘要： A method and apparatus for decoding digitally encoded communication signals transmitted over a fading channel. According to the disclosed embodiments, a sequence of test bits are transmitted in each TDMA slots, and a mathematical distance (e.g., a Hamming or Euclidean distance) is calculated and used to determine reliability information indicative of the reliability of the bits or symbols in a received time slot. Alternatively, a concatenated coding scheme can be used to transmit digital communication signals. Reliability information can be generated using the inner code and the output of the inner decoder.
摘要翻译： 一种用于解码通过衰落信道发送的经数字编码的通信信号的方法和装置。 根据所公开的实施例，在每个TDMA时隙中发送测试比特序列，并且计算数学距离（例如，汉明或欧几里德距离），并用于确定指示在一个或多个位置中的比特或符号的可靠性的可靠性信息 收到时间段 或者，可以使用级联编码方案来发送数字通信信号。 可以使用内部代码和内部解码器的输出来生成可靠性信息。
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公开(公告)号：US06314081B1
公开(公告)日：2001-11-06
申请号：US08588507
申请日：1996-01-18
IPC分类号： H04J1100
CPC分类号： H04W4/14 , H04B7/18567
摘要： A communication system and method for transmitting relatively short data messages in the communication system. A dedicated frequency is sequentially switched into each of a plurality of satellite beams or traffic channels to transmit data messages at an increased power level to provide an increased signal margin. The increased power level of the dedicated frequency can be combined with coding and bit and message repetition to further increase the signal margin.
摘要翻译： 一种用于在通信系统中发送相对短的数据消息的通信系统和方法。 专用频率被顺序地切换到多个卫星波束或业务信道中的每一个以在增加的功率电平上发送数据消息以提供增加的信号余量。 专用频率的增加的功率电平可以与编码和比特和消息重复组合以进一步增加信号余量。
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83.发明授权公开(公告)号：US06301231B1
公开(公告)日：2001-10-09
申请号：US09089192
申请日：1998-06-02
IPC分类号： H04B7185
CPC分类号： H04B7/18534
摘要： A satellite communication system includes Earth-based terminal and a satellite constellation in non-geosynchronous Earth orbits. When two or more satellites are within range of a first Earth-based terminal, the station requests a communication link with the first satellite at a first data rate. If the first satellite will accept data transfer at the first communication rate, the first Earth-based terminal transmits data to the first satellite at the requested first data rate. If, however, the first satellite will not accept data transfer at the requested first data rate, the first Earth-based terminal transmits a first portion of the data to the first satellite at a second data rate and transmits a second portion of the data, different from the first portion of the data, to the second satellite at a third data rate. The first and second satellites relay the respective data portions to a second Earth-based terminal, either directly or via additional satellites. The second Earth-based terminal reassembles the first and second data portions to recover the original data. The data transfer may be unequal error correction encoded data whereby the second Earth-based terminal may recover the original data from only a portion of the received error correction encoded data.
摘要翻译： 卫星通信系统包括地球终端和非地球同步地球轨道中的卫星星座。 当两个或更多个卫星在第一地球终端的范围内时，站以第一数据速率请求与第一卫星的通信链路。 如果第一卫星将以第一通信速率接受数据传输，则第一地基终端以所请求的第一数据速率向第一卫星发送数据。 然而，如果第一卫星不以所请求的第一数据速率接受数据传输，则第一地基终端以第二数据速率向第一卫星发送数据的第一部分，并发送数据的第二部分， 不同于数据的第一部分，以第三数据速率传送到第二卫星。 第一和第二卫星直接地或经由附加的卫星将相应的数据部分中继到第二个基于地球的终端。 第二个基于地球的终端重新组合第一和第二数据部分以恢复原始数据。 数据传输可以是不等的纠错编码数据，由此第二地基终端可以仅从接收的纠错编码数据的一部分恢复原始数据。
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84.发明授权公开(公告)号：US06192503B1
公开(公告)日：2001-02-20
申请号：US08911149
申请日：1997-08-14
IPC分类号： H03M1303
CPC分类号： H04L1/005 , H03M13/2975 , H04L1/0055 , H04L1/0066 , H04L1/007
摘要： A source sequence of symbols is communicated over a communications medium by encoding the source sequence according to respective first and second error correction codes to produce respective first and second encoded sequences of symbols. The first and second encoded sequences are processed to produce a communications signal, which is then communicated over the communications medium. The communicated communications signal is processed to produce first and second received sequences of symbols corresponding to the first and second encoded sequences, respectively. The first and second received sequences are selectively recursively decoded according to the associated error correction codes augmented by previous estimates of a symbol of the source sequence to repeatedly produce revised estimates of the symbol until an estimate satisfying a predetermined reliability criteria is obtained.
摘要翻译： 通过在源通信介质上通过根据相应的第一和第二纠错码对源序列进行编码来传送符号的源序列，以产生相应的第一和第二编码符号序列。 处理第一和第二编码序列以产生通信信号，然后通信信号在通信介质上传送。 所传送的通信信号被处理以分别产生对应于第一和第二编码序列的第一和第二接收的符号序列。 根据由源序列的符号的先前估计增加的相关联的纠错码来选择性地递归地解码第一和第二接收序列，以重复产生符号的修正估计，直到获得满足预定可靠性标准的估计。
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公开(公告)号：US5914942A
公开(公告)日：1999-06-22
申请号：US736954
申请日：1996-10-25
CPC分类号： H04B7/18563
摘要： A satellite-cellular communication system includes a satellite based transceiver for transceiving two-way communications originated at a user terminal. As a part of call set up, a controller determines whether the user terminal should transmit in the uplink in either a wide band mode of operation or in a narrow band mode of operation. The controller then specifies to the user terminal the mode of operation through the transceiver.Whether the user terminal transmits in the uplink in a wide band or in a narrow band mode depends upon factors including the type of device, channel usage and efficiency in the channels to and from the satellite transceiver and the signal quality of the signals received at the transceiver.
摘要翻译： 卫星蜂窝通信系统包括用于收发在用户终端发起的双向通信的基于卫星的收发信机。 作为呼叫建立的一部分，控制器确定用户终端是应在宽带操作模式还是在窄带操作模式中在上行链路中进行发送。 然后，控制器通过收发器向用户终端指定操作模式。 用户终端在宽带还是窄带模式下在上行链路中的发送取决于包括设备类型，信道使用情况以及卫星收发信机的频道使用效率以及在卫星收发信机接收的信号的信号质量等因素。 收发器。
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86.发明授权Synchronization method, and associated circuitry, for synchronizing a receiver with a transmitter 失效同步方法和相关电路，用于使接收机与发射机同步
公开(公告)号：US5883929A
公开(公告)日：1999-03-16
申请号：US626807
申请日：1996-04-03
CPC分类号： H04L7/046 , H04J3/0608
摘要： A synchronization method and apparatus for synchronizing a receiver, such as a radiotelephone operable in a cellular communication system with a transmitter. Synchronization sequences are transmitted as parts of a control signal to the receiver. The synchronization sequences are formed of either a dotting sequence or a set of m-sequences. Such synchronization sequences are of high margins and also permit synchronization of the user terminal responsive to a reduced number of calculations.
摘要翻译： 一种用于使诸如在蜂窝通信系统中可操作的无线电话机的接收机与发射机同步的同步方法和装置。 同步序列作为控制信号的一部分被发送到接收机。 同步序列由点序列或一组m序列组成。 这样的同步序列具有高边距并且还允许响应于减少的计算数量来同步用户终端。
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公开(公告)号：US5633875A
公开(公告)日：1997-05-27
申请号：US487735
申请日：1995-06-07
IPC分类号： B61L25/02 , G01S5/00 , G01S5/14 , G01S19/42 , G08G1/123 , G08G1/127 , H04B7/212 , H04B7/24 , H04J13/02 , H04B7/216
CPC分类号： B61L25/021 , B61L25/025 , G01S19/42 , G01S5/0027 , G01S5/14 , G08G1/127 , B61L2205/04
摘要： A protocol and mechanism which provide for centralized asset tracking communications from a central station are based on a control/polling forward channel; i.e., a narrow band channel from the central station to tracking units affixed to the assets. A narrow band service channel is used by the asset tracking units to transmit to the central station to aid the central station in efficient scheduling of asset reporting, and a plurality of narrow band channels that are appropriately multiplexed are used for conveyance of data from the asset tracking units to the central station.
摘要翻译： 提供来自中心站的集中资产跟踪通信的协议和机制基于控制/轮询前向信道; 即从中心站到贴附于资产的跟踪单位的窄带信道。 资产跟踪单位使用窄带业务信道向中心站发送信号，以帮助中心站进行资产报告的有效调度，并将适当多路复用的多个窄带信道用于从资产传输数据 跟踪单位到中心站。
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公开(公告)号：US5604806A
公开(公告)日：1997-02-18
申请号：US376144
申请日：1995-01-20
CPC分类号： H04L9/0838 , H04B17/24 , H04J13/00 , H04K1/00 , H04L2209/80
摘要： Characteristics of the radio channel are used to establish key sequences for use in encrypting communicated information. These characteristics are the short-term reciprocity and rapid spatial decorrelation of phase of the radio channel. The keys can be established with computations equivalent to a bounded distance decoding procedure, and the decoder used to establish a key may be used for processing the subsequent data transmission. Compared to classical and public-key systems, an alternative mechanism for establishing and sharing key sequences that depends on a physical process is provided in which each party need not generate a pseudorandom quantity because the necessary randomness is provided by the temporal and spatial non-stationarity of the communication channel itself. By using a channel decoder, the probability of two users establishing the same secret key is substantially unity, and the probability of an eavesdropper establishing the same key is substantially zero. Also, the number of possible keys is large enough that finding the correct one by exhaustive search is impractical.
摘要翻译： 无线电信道的特征用于建立用于加密通信信息的密钥序列。 这些特征是无线电信道相位的短期互惠和快速空间去相关。 可以通过与有界距离解码过程等效的计算来建立密钥，并且用于建立密钥的解码器可以用于处理随后的数据传输。 与古典和公钥系统相比，提供了一种用于建立和共享依赖于物理过程的密钥序列的替代机制，其中每个方不需要生成伪随机数，因为必要的随机性由时间和空间非平稳性 的通信信道本身。 通过使用信道解码器，建立相同密钥的两个用户的概率基本上是一致的，并且建立相同密钥的窃听者的概率基本为零。 此外，可能的键的数量足够大，通过穷举搜索找到正确的键是不切实际的。
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89.发明授权Trellis coding technique to improve adjacent channel interference protection ratio in land mobile radio systems 失效网格编码技术提高了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：US5311552A
公开(公告)日：1994-05-10
申请号：US898670
申请日：1992-06-15
CPC分类号： H04L27/186 , H03M13/25
摘要： An optimum communication system for communicating on adjacent frequency bands with minimal interference between adjacent channels comprises an encoder that is serially coupled to a mapper and two parallel processing branches, each processing 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, and an rf amplifier having a transmit antenna. The encoder is optimized by choosing a desired minimum Euclidean distance (DMED) between symbols, an encoder alphabet and a number of constellation points, permutating all possible encoder states and all possible input symbols to result in a plurality of encoder sets U, determining an in-band to adjacent band power ratio P.sub.ib /P.sub.ab for each code set is determined, discarding code sets U that having a minimum distance between symbol sets that do not exceed DMED, shifting by 90 degrees with respect to each other the phase of the signals passing through the modulators, and transmitting to a receiver the summation of the signals in each one of the parallel processing branches, whereby the encoder produces the code set of the remaining sets having the largest in-band to adjacent band power ratio P.sub.ib /P.sub.ab resulting in a transmitted signal having a spectrum that maximizes the ratio of in-band to adjacent band power for LMR systems. Maximizing the in-band to adjacent band power increases the ACIPR and also allows for increased data transmission rates.
摘要翻译： 用于在相邻频道之间以最小干扰在相邻频带上通信的最佳通信系统包括串行耦合到映射器和两个并行处理分支的编码器，每个处理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。 两个调制器耦合到一个夏天，一个射频放大器具有发射天线。 编码器通过在符号，编码器字母表和多个星座点之间选择期望的最小欧几里德距离（DMED）来优化，排列所有可能的编码器状态和所有可能的输入符号，以产生多个编码器集合U， 确定每个代码集的带到相邻带功率比Pib / Pab，丢弃具有不超过DMED的符号集之间的最小距离的代码集合U，相对于彼此相对于信号通过的相位相移90度 通过调制器，并且向接收机发送每个并行处理分支中的信号的总和，由此编码器产生具有最大带内至相邻频带功率比Pib / Pab的剩余组的码集，导致 具有使LMR系统的带内相邻带功率的比率最大化的频谱的发射信号。 将带内最大化到相邻频带功率增加了ACIPR，并且还允许增加数据传输速率。
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公开(公告)号：US09277032B2
公开(公告)日：2016-03-01
申请号：US13526518
申请日：2012-06-19
IPC分类号： H04J3/22 , H04L29/06 , H04L12/707
摘要： The subject disclosure is generally directed towards a technology by which non-contiguous channels of unequal bandwidth may be aggregated for use by communication devices. A data stream is partitioned (e.g., via puncturing) into partitioned data streams for communication over aggregated non-contiguous channels, one partitioned data stream per channel, in which partitioning is based upon each channel's bandwidth. Secondary puncturing may be used on any partitioned data stream that is to be transmitted over a channel associated with a regulatory constraint, e.g., a regulatory mask. Database querying, which may include providing device filter characteristics, may be used to obtain the set of channels available for use, along with any regulatory mask associated with a channel.
摘要翻译： 主题公开通常涉及一种技术，通过该技术不均匀带宽的不连续信道可被聚合以供通信设备使用。 数据流被分割（例如通过删截）到分割数据流中，用于通过聚合的非连续通道进行通信，每个通道一个分区数据流，其中分区基于每个通道的带宽。 次要穿孔可以用于要通过与调节约束（例如调节掩模）相关联的信道发送的任何分区数据流。 数据库查询（可能包括提供设备过滤器特性）可用于获得可用于使用的通道组以及与通道相关联的任何调节掩码。
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