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公开(公告)号：US5345245A
公开(公告)日：1994-09-06
申请号：US82006
申请日：1993-06-24
CPC分类号： G01S19/07
摘要： Differential data signal transmission technique, providing a differential data signal transmission technique inclusive of the correcting factor that requires no transmitter/receiver other than the GPS receiver, comprises the use of a differential ranging system where spread spectrum signals (SS signal) are multiplied at the same frequency, transmission rate, and modulation method used by the GPS satellites, but with different codes from those used by the GPS satellites, the SS signals used to transmit correcting factor from an earth station on the ground to a mobile station on the ground carrying a GPS receiver via a geostationary orbit satellite or a low earth orbit satellite.
摘要翻译： 差分数据信号传输技术提供包括不需要GPS接收机以外的发射机/接收机的校正因子的差分数据信号传输技术，包括使用差分测距系统，其中扩频信号（SS信号）在 GPS卫星使用的相同的频率，传输速率和调制方式，但是使用与GPS卫星使用的代码不同的代码，SS信号用于将地面站上的地面站的校正因子传送到地面上的移动台 通过地球同步轨道卫星或低地球轨道卫星的GPS接收机。
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公开(公告)号：US5490284A
公开(公告)日：1996-02-06
申请号：US247325
申请日：1994-05-23
CPC分类号： H04B7/18563 , H04W84/06 , H04W88/02 , H04W88/06
摘要： Through utilization of a transportable earth station capable of communicating with both of a mobile satellite communication system and a terrestrial based mobile communication system and a portable terminal which is capable of radio communication with the transportable earth station and used in the terrestrial based mobile communication system, it is possible to communicate with both of the terrestrial based mobile communication system and the mobile satellite communication system by only one portable terminal in a wide variety of communication environments.
摘要翻译： 通过利用能够与移动卫星通信系统和地面移动通信系统进行通信的可移动地球站和能够与可移动地球站进行无线电通信并在地面移动通信系统中使用的便携式终端， 可以通过在各种通信环境中的一个便携式终端与地面移动通信系统和移动卫星通信系统两者进行通信。
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公开(公告)号：US5774462A
公开(公告)日：1998-06-30
申请号：US907777
申请日：1997-08-11
申请人： Hiroyasu Ishikawa , Hideo Kobayashi
发明人： Hiroyasu Ishikawa , Hideo Kobayashi
CPC分类号： H04J3/0608 , G06F7/02 , H04L7/042 , G06F2207/025
摘要： In a time division multiplex (TDM) signal in which a symbol is sent one by one periodically, a unique word in the TDM signal is recognized quickly in a receiving station. A receive station has essentially N number of correlators each having a specific unique word pattern. A unique word pattern in each correlator is obtained by shifting by predetermined symbols cyclically from a reference unique word pattern. Each correlator provides a correlation value between a received TDM signal which includes a unique word and a unique word pattern defined in the correlator. Among outputs of N number of correlation values, which exceed a predetermined threshold value, the correlator which provides the maximum correlation value is selected, and the receive timing of the unique word is determined by the correlator thus selected.
摘要翻译： 在周期性地逐个发送符号的时分复用（TDM）信号中，TDM信号中的唯一字在接收站中被快速识别。 接收站具有基本上N个相关器，每个具有特定唯一的字模式。 通过从参考唯一字模式循环移位预定符号，可获得每个相关器中的唯一字模式。 每个相关器在包括唯一字的接收TDM信号和在相关器中定义的唯一字模式之间提供相关值。 在N个相关值的超过预定阈值的输出中，选择提供最大相关值的相关器，并且由所选择的相关器确定唯一字的接收定时。
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4.发明授权Selection diversity system using decision feedback equalizer in digital mobile telecommunication systems 失效在数字移动电信系统中使用决策反馈均衡器的选择分集系统
公开(公告)号：US5455844A
公开(公告)日：1995-10-03
申请号：US181197
申请日：1994-01-13
申请人： Hiroyasu Ishikawa , Hideo Kobayashi
发明人： Hiroyasu Ishikawa , Hideo Kobayashi
摘要： A selection diversity system using a decision feedback equalizer which has excellent tracking ability performance and equalization ability performance for frequency selective fading and a diversity effect against Rayleight fading. In a selection diversity system using a decision feedback equalizer, a decision data symbol of the equalizer output of a branch in which an average estimation error over a plurality of symbols is minimum is selected and combined, and the selected decision data symbol is used to recalculate the estimation error of every decision feedback equalizer and the tap gain coefficient of the decision feedback equalizer is updated using the recalculated estimation error, thereby overcoming the step out by the integration of the estimation error and the random selection error which is caused by the selective combined diversity system.
摘要翻译： 一种使用判决反馈均衡器的选择分集系统，其对于频率选择性衰落具有优异的跟踪能力性能和均衡能力性能以及对瑞利衰落的分集效应。 在使用判决反馈均衡器的选择分集系统中，选择并组合多个符号中的平均估计误差最小的分支的均衡器输出的判定数据符号，并且使用所选择的判定数据符号重新计算 使用重新计算的估计误差来更新每个判决反馈均衡器的估计误差和判定反馈均衡器的抽头增益系数，从而克服由选择性组合引起的估计误差和随机选择误差的积分 多样性系统。
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公开(公告)号：US6154506A
公开(公告)日：2000-11-28
申请号：US070931
申请日：1998-05-01
CPC分类号： H04L7/0334 , H04L7/0331
摘要： A timing recovery and tracking method and apparatus with respect to data signal in a digital communication system is provided. The method includes a step of setting a time window for making a decision based upon a predetermined threshold level, the time window having a time period corresponding to a transmission data rate in the digital communication system, a step of detecting a time duration positioned within the time window, a level of a received signal being higher than the predetermined threshold level during the time duration, a step of assuming a substantially middle point of the time duration as an optimum decision point of the received signal, and a step of updating the time window so that the updated time window has its center at a position of the assumed optimum decision point.
摘要翻译： 提供了一种关于数字通信系统中的数据信号的定时恢复和跟踪方法和装置。 该方法包括以下步骤：基于预定阈值水平设置用于进行判定的时间窗口，该时间窗口具有与数字通信系统中的传输数据速率对应的时间段，检测位于该数据通信系统内的时间段的步骤 在所述持续时间期间接收信号的电平高于所述预定阈值电平的步骤，将所述持续时间的大致中点作为所述接收信号的最佳判定点的步骤，以及更新所述时间窗口的步骤 窗口，使得更新的时间窗口的中心位于假定的最佳决策点的位置。
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公开(公告)号：US6104746A
公开(公告)日：2000-08-15
申请号：US925319
申请日：1997-09-08
CPC分类号： H04L27/2602 , H04B1/707 , H04B2201/70703
摘要： A combined channel or a composite channel is to be transformed into a plurality of element channels. The composite channel may be either shared by a plurality of communication stations on time division multiplex basis, or used by a single communication station. In a transmit side, a serial data information which is called a composite channel is transformed to parallel form associated with a plurality of element channels, each of which is spread by using a single common PN code. Each spread element channels are frequency converted to radio frequency so that the center carrier frequency is offset from that of adjacent element channel by an integer multiple of information transmission rate of each element channel, and frequency band occupied by spread element channels overlap with one another. Each element channels thus spread and frequency converted are combined on frequency axis, and transmitted to a receive side. Thus, all the element channels are synchronized with one another because of the use of a single common PN code, and receive level of signal of each element channel is uniform, irrespective of a number of communication stations, and therefore, high quality communication with no interference is obtained in a relatively narrow frequency band.
摘要翻译： 组合信道或复合信道将被转换成多个元素信道。 复合信道可以由多个通信站以时分复用为基础共享，或由单个通信站使用。 在发送侧，称为复合信道的串行数据信息被变换成与多个元素信道相关联的并行形式，每个元素信道通过使用单个公共PN码进行扩展。 每个扩展元素信道被频率转换为射频，使得中心载波频率与相邻元素信道的中心载波频率偏移每个元素信道的信息传输速率的整数倍，并且扩频元件信道占据的频带彼此重叠。 如此扩频和频率转换的每个元素信道在频率轴上组合，并传输到接收侧。 因此，由于使用单个公共PN码，所有元件信道彼此同步，并且每个元件信道的接收信号水平是均匀的，而与通信站数量无关，因此，高质量的通信没有 在相对窄的频带获得干扰。
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公开(公告)号：US5974082A
公开(公告)日：1999-10-26
申请号：US958094
申请日：1997-10-27
CPC分类号： H04J13/00 , H04B7/2618 , H04L5/06
摘要： A spread spectrum communications system includes at least one communication station for transmitting a plurality of digital information data sequences via a plurality of communication channels by using the same PN code sequence. The communication station spreads the respective digital information data sequences by the PN code sequence to provide spread spectrum signals, modulates the spread spectrum signals by respective carriers having different frequencies from each other to provide modulated signals, and then transmits the modulated signals via the communication channels respectively. A frequency interval of the carrier frequencies is determined to an even-numbered multiple of a symbol rate of the transmitted digital information data sequences.
摘要翻译： 扩展频谱通信系统包括至少一个通信站，用于通过使用相同的PN码序列经由多个通信信道发送多个数字信息数据序列。 通信站通过PN码序列扩展各个数字信息数据序列，以提供扩频信号，通过具有不同频率的各个载波调制扩频信号以提供调制信号，然后经由通信信道发送调制信号 分别。 载波频率的频率间隔被确定为发送的数字信息数据序列的符号率的偶数倍。
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公开(公告)号：US5588026A
公开(公告)日：1996-12-24
申请号：US361707
申请日：1994-12-22
申请人： Hiroyasu Ishikawa , Hideo Kobayashi
发明人： Hiroyasu Ishikawa , Hideo Kobayashi
IPC分类号： H03J7/02 , H04L27/233 , H03D3/00
CPC分类号： H03J7/02 , H04L27/2332
摘要： A frequency offset compensation method has the steps of raising the detected signal to the M-th power to remove a modulation factor from the received signal, and accumulating the M-th power signals for N (N is an integer) symbols to derive a phase component of the accumulated M-th power signals. Then, the derived phase component is divided into M so as to obtain an estimation value with respect to phase shift due to frequency offset which represents frequency deviation from a true carrier frequency contained in the received signal, and the received signal is multiplied by the obtained estimation value in a form of conjugate complex number to remove the phase shift due to the frequency offset from the received signal.
摘要翻译： 频率偏移补偿方法具有以下步骤：将检测到的信号提升到M次方，以从接收信号中去除调制因子，并且累积第N个功率信号N（N是整数）符号以导出相位 积累的M次方信号的分量。 然后，将导出的相位分量分割为M，以获得由于频率偏移而导致的相移的估计值，其表示与包含在接收信号中的真实载波频率的偏差，并且接收信号乘以所获得的相位分量 以共轭复数形式的估计值，以消除由于从接收信号的频率偏移引起的相移。
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9.发明授权
公开(公告)号：US5969669A
公开(公告)日：1999-10-19
申请号：US566737
申请日：1995-12-04
CPC分类号： G01S5/12 , H04B7/18547
摘要： A method is disclosed for uniquely determining the position of a mobile earth station in a mobile satellite communication system which employs a non-geostationary satellite with a multi-spot beams. A given point of a preknown position on the earth surface is defined as the center coordinate of a three-dimensional coordinate axis, information on the measured distance and Doppler shift amount between a mobile earth station of an unknown position and a non-geostationary satellite is used to repeat the estimation of the position of the mobile earth station a plurality of times, thereby obtaining the position of the earth station with high accuracy. Furthermore, by observing the estimated positions of the mobile earth station obtained as a plurality of solutions at proper time intervals, comparing with one another the movements of the respective estimated positions occurring with the local time proceeds and selecting the estimated position of the minimum movement, the estimated position of the mobile earth station is uniquely determined relative to its true position.
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10.发明授权Method for determining position of mobile earth station in satellite communication system 失效确定卫星通信系统中移动地球站位置的方法
公开(公告)号：US6166687A
公开(公告)日：2000-12-26
申请号：US353543
申请日：1999-07-14
CPC分类号： G01S5/12 , H04B7/18547
摘要： A method is disclosed for uniquely determining the position of a mobile earth station in a mobile satellite communication system which employs a non-geostationary satellite with a multi-spot beams. A given point of a preknown position on the earth surface is defined as the center coordinate of a three-dimensional coordinate axis, information on the measured distance and Doppler shift amount between a mobile earth station of an unknown position and a non-geostationary satellite is used to repeat the estimation of the position of the mobile earth station a plurality of times, thereby obtaining the position of the earth station with high accuracy. Furthermore, by observing the estimated positions of the mobile earth station obtained as a plurality of solutions at proper time intervals, comparing with one another the movements of the respective estimated positions occurring with the local time proceeds and selecting the estimated position of the minimum movement, the estimated position of the mobile earth station is uniquely determined relative to its true position.
摘要翻译： 公开了一种用于在采用具有多点波束的非对地静止卫星的移动卫星通信系统中唯一地确定移动地球站的位置的方法。 将地球表面上预先知道的位置的给定点定义为三维坐标轴的中心坐标，关于未知位置的移动地球站与非对地静止卫星之间的测量距离和多普勒频移量的信息是 用于多次重复对移动地球站的位置的估计，从而以高精度获得地球站的位置。 此外，通过以适当的时间间隔观察作为多个解决方案获得的移动地球站的估计位置，相对于当前时间发生的各个估计位置的移动进行并选择最小运动的估计位置， 移动地球站的估计位置相对于其真实位置是唯一确定的。
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