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公开(公告)号：US5481532A
公开(公告)日：1996-01-02
申请号：US267347
申请日：1994-06-29
摘要： A highly fault tolerant method of radio communication of information in the form of a message packet employs a distributed network of transmitter/receivers `transceivers` each having a unique identification ("ID") number. An initiating transceiver creates a message packet having the ID of a transceiver intended to receive the message packet. It then broadcasts the message packet to transceivers within its transmission range. Each transceiver which receives the message packet checks to see if there are errors and sends an acknowledgement if no errors. The transceivers determine valid message packets by determining if the message has not expired, if it has not been seen before and there were no errors in the received message packet. The transceiver also determines if the transceiver ID in the message packet match its own transceiver ID, and if it does, is the message has been successfully transmitted to its intended transceiver. If the message packet is valid and the transceiver IDs do not match, the transceiver broadcasts the message to other local transceivers until a predetermined number of acknowledgements are received, or until the message expires. The transceivers which receive the message packet repeat the process.
摘要翻译： 以消息分组形式的信息的无线电通信的高度容错方法采用每个具有唯一标识（“ID”）号码的发射机/接收机收发机的分布式网络。 启动收发器创建具有旨在接收消息分组的收发器的ID的消息分组。 然后，它将消息包广播到其传输范围内的收发器。 接收消息包的每个收发器检查是否存在错误，并且如果没有错误则发送确认。 如果接收到的消息包中没有出现任何错误，则收发器通过确定消息是否尚未过期来确定有效的消息包。 收发器还确定消息包中的收发器ID是否与其自己的收发器ID匹配，如果是，则将消息成功发送到其预定的收发器。 如果消息包有效并且收发器ID不匹配，则收发器将消息广播到其他本地收发器，直到接收到预定数量的确认，或直到消息过期为止。 接收消息包的收发器重复该过程。
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公开(公告)号：US5166953A
公开(公告)日：1992-11-24
申请号：US605714
申请日：1990-10-30
IPC分类号： H04B1/7136 , H04B1/715 , H04K3/00
CPC分类号： H04B1/7136 , H04B1/715 , H04K3/25 , H04K3/827 , H04B2001/71362 , H04B2001/7152
摘要： A countermeasure to a partial-band follower jammer for frequency hopping spread spectrum communication systems employs an M-ary orthogonal frequency shift keyed (FSK) signaling system having q frequency channels available for hopping. During each signaling interval, the transmitter and receiver operate in either a conventional or unconventional mode. The conventional mode is selected by the transmitter and the receiver with a pseudorandom probability p.sub.c. In this mode, the transmitter transmits one of r tones within the corresponding hop (i.e., within one of q channels), and log.sub.2 r information bits are conveyed, while the receiver comprises a dehopper followed by noncoherent matched filters. The unconventional mode is selected with probability 1-p.sub.c. In this mode, the transmitter randomly chooses one of the r tones and transmits it in one of r channels within each hop, where the r channels are selected pseudorandomly. In the unconventional mode, log.sub.2 r information bits are transmitted and the receiver comprises a bank of r radiometers.
摘要翻译： 用于跳频扩频通信系统的部分带跟随器干扰器的对策采用具有可用于跳频的q个频率信道的M进制正交频移键控（FSK）信令系统。 在每个信令间隔期间，发射机和接收机以常规或非常规模式工作。 常规模式由具有伪随机概率pc的发射机和接收机选择。 在该模式中，发射机在对应的跳频（即，在q个信道之一内）之间发送r个音调中的一个，并且传送log2r信息比特，而接收机包括后卫非相干匹配滤波器。 非常规模式以概率1-pc选择。 在这种模式下，发射机随机选择一个r个音调，并在每个跳频中的一个r个信道中发送，其中r个信道被伪随机地选择。 在非常规模式下，发送log2r信息位，并且接收器包括一组r辐射计。
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公开(公告)号：US5563906A
公开(公告)日：1996-10-08
申请号：US407560
申请日：1995-03-20
CPC分类号： H04B1/69
摘要： The present invention provides a novel Geometric Harmonic Modulation (GHM) method. The GHM method functions in two modes, a preamble mode and a traffic mode. During the preamble mode, n+1 frequencies are each offset by a predetermined phase in a transmit unit and passed through a channel to a receive unit. The set of phases is used as the spreading code in the transmit unit, and also acts as an `address` of intended receive units. The receive unit monitors preamble signals to determine the phases. When it recognizes a set of phases, or `address`, which pertains to itself, the receive unit stores the phases and uses these phases to despread and decode the appended message. After the preamble mode is finished, the GHM modulator enters the traffic mode and requests the message to be transmitted from the message source. A traffic carrier waveform is created by multiplying tones, each having its specific phase. An analog or binary message is encoded by modulating the traffic carder waveform. The receive unit detects a preamble carrier and recovers the particular preamble phases to be used as the despreading `key`. The receive unit then employs the phases in despreading the received signal to recover the transmitted binary message.
摘要翻译： 本发明提供了一种新颖的几何谐波调制（GHM）方法。 GHM方法在两种模式中起作用，即前导码模式和流量模式。 在前导码模式期间，n + 1个频率各自在发送单元中被预定的相位偏移并且通过信道被传送到接收单元。 该组相位被用作发送单元中的扩展码，并且还用作预期接收单元的“地址”。 接收单元监视前置信号以确定相位。 当它识别与本身相关的一组相位或“地址”时，接收单元存储相位并使用这些相位对所附加的消息进行解扩和解码。 在前导码模式完成之后，GHM调制器进入业务模式，并请求消息从消息源发送。 通过乘以每个具有其特定相位的音调来创建交通载波波形。 模拟或二进制消息通过调制业务量卡波形进行编码。 接收单元检测前同步码载波并恢复要用作解扩“密钥”的特定前同步码相位。 然后，接收单元采用解扩接收信号的相位来恢复发送的二进制消息。
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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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6.发明授权Instrument for detecting potential future failures of valves in critical control systems 失效用于检测关键控制系统阀门潜在未来故障的仪器
公开(公告)号：US5616824A
公开(公告)日：1997-04-01
申请号：US517884
申请日：1995-08-21
CPC分类号： F16K37/0083
摘要： Apparatus for monitoring the health and response of critical electromechanical control valves to detect the likelihood of future valve malfunction includes the use of Fourier transform decomposition and time-domain wavelets to selectively enhance portions of the valve response signal for comparison with a normal valve response signal.
摘要翻译： 用于监测关键机电控制阀的健康和响应以检测未来阀故障的可能性的装置包括使用傅里叶变换分解和时域小波来选择性地增强阀响应信号的部分以与正常阀响应信号进行比较。
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公开(公告)号：US5532860A
公开(公告)日：1996-07-02
申请号：US406437
申请日：1995-03-20
申请人： John E. Hershey , Nabeel A. Riza , Amer A. Hassan
发明人： John E. Hershey , Nabeel A. Riza , Amer A. Hassan
摘要： A spatial synchronization method for an optical communications system includes the step of transmitting from a transmit aperture a pyramidal synchronizing profile so as to sequentially spatially register a user identification speckle pattern at a receive aperture. The iterative patterns in the pyramidal synchronizing profile detected by the receive array are processed and correlated with a library of respective user pyramidal synchronizing profiles so as to match and register the speckle pattern for a particular user. Registration of the user speckle pattern provides an offset value representing the spatial relation of a reference point of the user's pattern to a corresponding reference point of the receive aperture, which offset information is applied to a receive pattern processor so that the receive aperture is aligned with the transmitted speckle patterns.
摘要翻译： 用于光通信系统的空间同步方法包括从发射孔径发送锥体同步分布的步骤，以便在接收孔径处依次空间地登记用户识别散斑图案。 由接收阵列检测的金字塔形同步分布中的迭代模式被处理并与相应用户锥体同步分布的文库相关联，以便匹配并注册特定用户的散斑图案。 用户斑点图案的注册提供表示用户图案的参考点与接收孔径的相应参考点的空间关系的偏移值，该偏移信息被施加到接收图案处理器，使得接收孔径与 传输的斑点图案。
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公开(公告)号：US5519692A
公开(公告)日：1996-05-21
申请号：US407554
申请日：1995-03-20
CPC分类号： H04B1/69 , H04L27/2601
摘要： A set of phases defining an `address` and a `spreading key` is selected. These are employed in determining a preamble waveform and a traffic waveform. The preamble carrier waveform is a sum of a set of tones each offset by its phase, whereas the traffic carrier waveform is the product of these same offset tones. The tones have frequencies which are geometrically increasing multiples of a fundamental frequency. The phases and magnitudes of the preamble and traffic carrier waveforms are determined and prestored in a transmit and receive unit storage device. An inverse discrete Fourier Transform unit (IDFT) in the transmit unit receives the phase preamble offsets and magnitudes from the storage unit and creates a preamble carrier signal transmitted to the receive unit which determines if the phases match those which it is to listen to. If not, the following message is ignored; if they are, the following message is despread and decoded. IDFT creates a traffic carrier waveform from the traffic phases and magnitudes. Binary information is encoded in the carrier, processed and transmitted to the receive unit. A discrete Fourier Transform unit converts the received signal into phases and magnitudes. A dot product unit determines a dot product of the phase and magnitudes of the received signal and the traffic carrier waveform over a number of frequencies. A decision unit determines a binary message from the dot product.
摘要翻译： 选择定义“地址”和“扩展密钥”的一组相位。 这些用于确定前导码波形和业务波形。 前导码载波波形是每个偏移其相位的一组音调的和，而业务载波波形是这些相同偏移音调的乘积。 音调具有几何上增加基频倍数的频率。 前导码和业务载波波形的相位和幅度被确定并预存储在发送和接收单元存储设备中。 发送单元中的离散傅里叶逆变换单元（IDFT）从存储单元接收相位前导偏移量和幅度，并产生发送到接收单元的前导码载波信号，该信号确定相位是否匹配要收听的相位。 如果没有，则忽略以下消息; 如果它们是，则以下消息被解扩和解码。 IDFT从交通阶段和幅度创建一个载波波形。 二进制信息被编码在载体中，被处理并发送到接收单元。 离散傅立叶变换单元将接收的信号转换为相位和幅度。 点积单位确定接收信号的相位和幅度以及多个频率上的业务载波波形的积积。 决策单元从点积确定二进制消息。
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公开(公告)号：US5621417A
公开(公告)日：1997-04-15
申请号：US484754
申请日：1995-06-07
申请人： Amer A. Hassan , John E. Hershey
发明人： Amer A. Hassan , John E. Hershey
IPC分类号： G01C21/00 , G01S1/00 , G01S5/00 , G01S5/14 , G01S7/526 , G01S13/78 , G01S15/74 , G01S15/87 , G01S19/42 , G08B25/04 , H04B7/212 , G01S3/02
CPC分类号： G01S13/825 , G01S19/09 , G01S19/34 , G01S2205/002 , G01S5/0027
摘要： A tracking system for railcars is configured as a dynamic local area network having a master tracking unit and a plurality of slave tracking units, each tracking unit being affixed to a separate railcar. To improve reliability of communications between railcars, the distance from a master unit to a slave unit is estimated by comparing phase of a transmitted signal with that of the transmitted signal returned by another tracking unit in the network. Optionally, a determination is made as to whether the slave unit is "ahead" of or "behind" the master unit. Communication path loss between the master and slave units due to frequency selective fading may also be determined. A spectrum survey determines quality of the channel as to its capacity for passing data from the slave unit to the master unit.
摘要翻译： 用于轨道车辆的跟踪系统被配置为具有主跟踪单元和多个从属跟踪单元的动态局域网，每个跟踪单元被固定到单独的轨道车。 为了提高铁路车辆之间通信的可靠性，通过将发送信号的相位与网络中另一个跟踪单元返回的发送信号的相位进行比较来估计从主单元到从单元的距离。 可选地，确定从属单元是否在主单元的“前方”或“之后”。 也可以确定由于频率选择性衰落引起的主单元和从单元之间的通信路径损耗。 光谱测量可以确定通道的质量，以便其将数据从从属单元传送到主单元的能力。
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10.发明授权Protocol and mechanism for primary and mutter mode communication for asset tracking 失效用于资产跟踪的主要和嘟嘟模式通信的协议和机制
公开(公告)号：US5588005A
公开(公告)日：1996-12-24
申请号：US487272
申请日：1995-06-07
申请人： Irfan Ali , John E. Hershey , Stephen M. Hladik , Amer A. Hassan , Sandeep Channakeshu , Ravinder D. Koilpillai , Kenneth B. Welles, II , Harold W. Tomlinson
发明人： Irfan Ali , John E. Hershey , Stephen M. Hladik , Amer A. Hassan , Sandeep Channakeshu , Ravinder D. Koilpillai , Kenneth B. Welles, II , Harold W. Tomlinson
IPC分类号： G01C21/00 , B61L25/02 , G01S5/00 , G01S5/14 , G01S19/42 , G08B25/04 , G08G1/127 , H04B7/185 , H04B7/212 , H04L12/28 , H04L12/56 , H04Q7/00
CPC分类号： H04W84/12 , B61L25/021 , B61L25/025 , G01S5/0027 , G08G1/127 , H04B7/18545 , H04B7/18576 , H04W84/20 , B61L2205/04 , G01S19/09 , G01S19/14 , H04W8/02 , Y02B60/50
摘要： A mode of communication for asset tracking units involves communication between a central station and the individual tracking units, usually through a satellite link. This mode is the primary communication link for tracking the assets. A second mode is the local area network (LAN) or "mutter" mode, in which a subset of tracking units communicate with each other in a mobile LAN. This mode is used as the secondary communication mechanism to conserve power, since mutter mode communication requires much less energy for local communication between the tracking units as opposed to direct satellite communication with the central station. In addition, mutter mode leads to increased reliability of the asset tracking system by enabling tracking of units which have batteries too weak to support communication with the central station, but strong enough to support communication in mutter mode. The mutter mode is also useful in finding tracking units which are not communicating with the central station due primary communication equipment fault or other inhibiting condition.
摘要翻译： 用于资产跟踪单元的通信模式涉及通常通过卫星链路在中心站和各个跟踪单元之间的通信。 此模式是用于跟踪资产的主要通信链接。 第二模式是局域网（LAN）或“嘟嘟”模式，其中跟踪单元的子集在移动LAN中彼此通信。 该模式用作次要通信机制以节省功率，因为对于与中心站的直接卫星通信相反，跟踪单元之间的本地通信需要更少的能量。 此外，嘟嘟模式通过对具有电池太弱的单元进行跟踪以支持与中心站的通信，从而提高资产跟踪系统的可靠性，但足够强大以支持在嘟嘟模式下的通信。 由于主要通信设备故障或其他抑制条件，嘟嘟模式也可用于找到不与中心站通信的跟踪单元。
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