Using read lock capability for secure RFID authentication
    1.
    发明申请
    Using read lock capability for secure RFID authentication 审中-公开
    使用读取锁定功能进行安全的RFID认证

    公开(公告)号:US20080001724A1

    公开(公告)日:2008-01-03

    申请号:US11495673

    申请日:2006-07-31

    IPC分类号: H04Q5/22

    摘要: Methods, systems, and apparatuses for preventing unauthorized reading of identifying data stored in tags are described. A secure access identification number and associated read lock password are received. The secure access identification number and associated read lock passcode are transferred to the tag. The tag stores the secure access identification number and read lock passcode. A read lock command is transmitted to the tag. The tag is locked from being read for selected information, such as identifying information and user information, by the read lock command. In a further aspect, the secure access identification number is read from the read locked tag. The secure access identification number is associated with a passcode. The passcode is transmitted to the read locked tag. The tag disables the read lock if the passcode matches the previously received read lock password.

    摘要翻译: 描述用于防止未经授权读取存储在标签中的识别数据的方法,系统和装置。 接收到安全的访问标识号和相关的读锁密码。 安全访问标识号和相关的读锁密码被传送到标签。 该标签存储安全访问标识号和读取锁定密码。 读取锁定命令被发送到标签。 通过读取锁定命令,锁定标签被读取用于所选择的信息,例如识别信息和用户信息。 在另一方面,从读取锁定的标签中读取安全访问标识号。 安全访问标识号与密码相关联。 密码被传送到读锁定标签。 如果密码与以前收到的读锁密码相匹配,则标签会禁用读锁。

    RFID tag with programmable read range
    2.
    发明申请
    RFID tag with programmable read range 审中-公开
    具有可编程读取范围的RFID标签

    公开(公告)号:US20070273481A1

    公开(公告)日:2007-11-29

    申请号:US11440094

    申请日:2006-05-25

    IPC分类号: H04Q5/22

    CPC分类号: H01Q1/2225

    摘要: A system and method in a radio frequency identification (RFID) tag for responding to RFID reader communication signals is described. A strength of a signal from a reader is measured. A RFID read signal is received from the reader. A response to the read signal is enabled based on the measured strength.

    摘要翻译: 描述了用于响应RFID读取器通信信号的射频识别(RFID)标签中的系统和方法。 测量来自读取器的信号的强度。 从阅读器接收RFID读取信号。 基于测量的强度启用对读取信号的响应。

    Verification of singulated RFID tags by RFID readers
    5.
    发明申请
    Verification of singulated RFID tags by RFID readers 有权
    RFID阅读器对单片RFID标签的验证

    公开(公告)号:US20070257776A1

    公开(公告)日:2007-11-08

    申请号:US11412840

    申请日:2006-04-28

    IPC分类号: H04Q5/22

    摘要: Methods, systems, and apparatuses for verifying singulated tags are described. A radio frequency (RF) signal is transmitted to provide power to at least one tag. A powered tag is singulated. A delay time period is waited. A read verify command is transmitted to the singulated tag. A response is received to the read verify command. The response to the read verify command is verified to determine whether it was received from the singulated tag.

    摘要翻译: 描述用于验证单个标签的方法,系统和装置。 传输射频(RF)信号以向至少一个标签提供电力。 被动标签是单独的。 等待延迟时间。 读取验证命令被发送到单独的标签。 接收到读取验证命令的响应。 验证对读取验证命令的响应,以确定是否从单个标签接收。

    VSAT frequency source using direct digital synthesizer
    6.
    发明授权
    VSAT frequency source using direct digital synthesizer 失效
    VSAT频率源采用直接数字合成器

    公开(公告)号:US5995812A

    公开(公告)日:1999-11-30

    申请号:US523105

    申请日:1995-09-01

    IPC分类号: H04B7/185 H04B7/155

    CPC分类号: H04B7/18519

    摘要: A frequency generation device for a satellite communication system composed of a central hub station and a number of remote units. The remote units contain a single synthesizer located in an indoor unit. In this invention, the indoor-located synthesizer is a direct digital synthesizer which modulates the baseband signal and conveys the modulated signal to an outdoor unit for communication between the remote unit and the central hub. In the outdoor unit, the signal is converted directly by a fixed number to a Ku band frequency and transmitted to the central hub.

    摘要翻译: 一种用于卫星通信系统的频率发生装置,其由中央集线器站和多个远程单元组成。 远程单元包含位于室内单元中的单个合成器。 在本发明中,室内定位合成器是直接数字合成器,其对基带信号进行调制,并将调制信号传送到室外单元,用于远程单元和中央集线器之间的通信。 在户外单元中,信号被固定数字直接转换为Ku波段频率并传输到中央集线器。

    Low cost very small aperture satellite terminal
    7.
    发明授权
    Low cost very small aperture satellite terminal 失效
    低成本非常小的孔径卫星终端

    公开(公告)号:US5790601A

    公开(公告)日:1998-08-04

    申请号:US523309

    申请日:1995-09-05

    IPC分类号: H04B7/185 H03K7/06

    CPC分类号: H04B7/18517

    摘要: A remote ground terminal transmitter for transmitting a modulated data signal having a constant envelope amplitude. The remote ground terminal transmitter comprises a source of data signals, a modulator for providing a carrier signal, receiving a data signal from the source of data signals, and modulating the carrier signal with the received data signal so as to produce a constant envelope minimum shift key modulation signal. The transmitter further comprises a power amplifier which operates in the saturation mode to amplify the modulated carrier signal produced by the modulator to the desired power level.

    摘要翻译: 一种用于发送具有恒定包络幅度的调制数据信号的远程接地终端发射机。 远程接地终端发射机包括数据信号源,用于提供载波信号的调制器,从数据信号源接收数据信号,并用接收到的数据信号调制载波信号,以产生恒定的包络最小偏移 键调制信号。 发射机还包括在饱和模式下工作的功率放大器,以将由调制器产生的调制载波信号放大到期望的功率电平。

    Operation of low-cost, fixed output power radio in fixed gain mode
    8.
    发明授权
    Operation of low-cost, fixed output power radio in fixed gain mode 失效
    低成本,固定输出功率无线电在固定增益模式下的运行

    公开(公告)号:US5659892A

    公开(公告)日:1997-08-19

    申请号:US502029

    申请日:1995-07-13

    IPC分类号: H03G3/30 H04B7/005 H04B1/04

    摘要: A method and system for using a low-cost, fixed output power radio in a multi-carrier communication system is disclosed herein. This system measures the output power of the multiple channel units within the system, obtains the current output power of the system, calculates a composite power and an expected power, compares the expected power and the current output power to calculate a gain adjustment value, and adjusting the output power of the system via the amplifier. The method for adjusting the power can also allow at least one of the carriers in the multi-carrier system to operate in a burst mode, and at least one of the remaining carriers to operate in a continuous mode during power measurement and gain adjustment steps.

    摘要翻译: 本文公开了一种在多载波通信系统中使用低成本,固定输出功率无线电的方法和系统。 该系统测量系统内多个通道单元的输出功率,获得系统的当前输出功率,计算复合功率和预期功率,比较预期功率和电流输出功率以计算增益调整值,以及 通过放大器调整系统的输出功率。 用于调整功率的方法还可以允许多载波系统中的载波中的至少一个以突发模式操作,并且剩余载波中的至少一个在功率测量和增益调整步骤期间以连续模式操作。

    Method and apparatus for joint timing synchronization and frequency offset estimation
    9.
    发明授权
    Method and apparatus for joint timing synchronization and frequency offset estimation 失效
    联合定时同步和频偏估计的方法和装置

    公开(公告)号:US06363131B1

    公开(公告)日:2002-03-26

    申请号:US09109798

    申请日:1998-07-02

    IPC分类号: H04L700

    摘要: A burst analyzer is useful in a digital communication system in which a signal burst has a plurality of reference segments distributed within the signal burst for transmission of a plurality of reference signals. The burst analyzer includes a filter that compares the received signal, for each reference segment thereof, with each reference signal offset by one of a plurality of time offsets to generate correlation data. The burst analyzer then determines, for each reference segment of the signal burst, a maximum correlation value from the correlation data for each time offset. Then the burst analyzer determines the time offset at which a sum of the maximum correlation values, over the plurality of reference segments, is a maximum. The burst analyzer jointly generates a frequency domain representation of the correlation data associated with the time offset at which the maximum correlation sum is a maximum, and then determines a frequency at which the frequency domain representation is a maximum.

    摘要翻译: 突发分析器在数字通信系统中是有用的,其中信号突发具有分布在信号突发内的多个参考段,用于传输多个参考信号。 突发分析器包括一个滤波器,其对于每个参考信号段的接收信号与多个时间偏移中的一个偏移量的每个参考信号进行比较以产生相关数据。 脉冲串分析器然后根据每个时间偏移的相关数据确定信号脉冲串的每个参考段的最大相关值。 然后,脉冲串分析器确定在多个参考段上的最大相关值之和为最大值的时间偏移。 突发分析器共同地产生与最大相关和为最大的时间偏移相关联的相关数据的频域表示,然后确定频域表示为最大的频率。

    Leased line optimization and voice quality improvement in bandwidth constrained communication systems

    公开(公告)号:US06226304B1

    公开(公告)日:2001-05-01

    申请号:US09075568

    申请日:1998-05-11

    IPC分类号: H04B7185

    摘要: The present invention is embodied in a method an apparatus for reducing the number of leased E1 lines needed to backhaul communication traffic in a satellite communication situation. The present invention receives and decompressed a satellite signal. A copy of the compressed signal is then encoded into the least significant bits (LSBs) of the decompressed signal. The decompressed signal having the embedded information may be routed to an international PSTN network over leased communications lines. However, the compressed information is extracted from the decompressed signal and sent across the E1 lines, thereby conserving communication bandwidth and reducing the number of leased lines required. After passing through the E1 lines the information is decompressed and connected to the international PSTN network. Alternatively, the decompressed signal having the embedded information may be distributed to local PSTN networks, which interpret decompressed signals. The degradation in voice quality of the decompressed signal due to the embedding of the compressed information in negligible.