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1. 发明授权

US5475677A Compatible licensed and unlicensed band portable handset unit for TDMA wireless communications system 失效
标题翻译：用于TDMA无线通信系统的兼容许可和非授权频带便携式手机单元
公开(公告)号：US5475677A
公开(公告)日：1995-12-12
申请号：US366944
申请日：1994-12-29
申请人： Hamilton W. Arnold , Li F. Chang , Anthony R. Noerpel , Nelson R. Sollenberger , Robert A. Ziegler
发明人： Hamilton W. Arnold , Li F. Chang , Anthony R. Noerpel , Nelson R. Sollenberger , Robert A. Ziegler
IPC分类号： H04B1/40 , H04B7/06 , H04B7/08 , H04B7/26 , H04J3/00 , H04J4/00 , H04M1/00 , H04W4/18 , H04W88/02 , H04W88/06 , H04B1/56 , H04L5/14
CPC分类号： H04W88/06 , H04B1/005 , H04B1/406 , H04B7/0608 , H04B7/0805 , H04B7/2615 , H04J4/00 , H04B1/405 , H04W4/18 , H04W88/02
摘要： In a TDM/TDMA portable radio communications system, a portable handset is compatible for operation in both a frequency-division duplexing (FDD) mode for communication in the licensed portion of the Emerging Technologies frequency band, and in a time-division duplexing (TDD) mode for communication in the unlicensed portion of the Emerging Technologies frequency band. In the FDD mode, different frequencies are used to separate a downlink transmission to a portable from a port from an uplink transmission from a port to a portable. In the TDD mode, uplink and downlink transmissions are separated in different time-slots, but at the same frequency. The handset includes common transmit and receive circuitry that operates at fixed IF frequencies that are separated in frequency by the fixed FDD frequency difference between corresponding uplink and downlink signals. In the FDD mode, therefore, a frequency synthesizer (301), which is used to tune to transmit and receive at different frequencies from different ports, does not have to switch its frequency between transmitting and receiving a burst to and from a single port. In the TDD mode, however, even though uplink and downlink signals are at the same frequency, the synthesizer is switched in frequency between transmitting uplink and receiving downlink.
摘要翻译：在TDM / TDMA便携式无线电通信系统中，便携式手机兼容于用于在新兴技术频带的许可部分中进行通信的频分双工（FDD）模式以及时分双工（TDD））模式，用于在Emerging Technologies频段的未许可部分进行通信。在FDD模式中，使用不同的频率将从端口的便携式终端的下行链路传输从从端口到便携式的上行链路传输分离。在TDD模式中，上行链路和下行链路传输在不同的时隙中分离，但是频率相同。手机包括以固定的IF频率工作的公共发射和接收电路，频率上分离相应的上行链路和下行链路信号之间的固定FDD频率差。因此，在FDD模式中，用于调谐以从不同端口发送和接收不同频率的频率合成器（301）不必在从单个端口发送和接收脉冲串之间切换其频率。然而，在TDD模式中，即使上行链路和下行链路信号处于相同的频率，合成器在发送上行链路和接收下行链路之间的频率也被切换。

2. 发明授权

US5084891A Technique for jointly performing bit synchronization and error detection in a TDM/TDMA system 失效
标题翻译：在TDM / TDMA系统中共同执行比特同步和错误检测的技术
公开(公告)号：US5084891A
公开(公告)日：1992-01-28
申请号：US404946
申请日：1989-09-08
申请人： Sirikiat Ariyavisitakul , Li F. Chang , Nelson R. Sollenberger
发明人： Sirikiat Ariyavisitakul , Li F. Chang , Nelson R. Sollenberger
IPC分类号： H03M13/33 , H04B7/26 , H04L1/00 , H04L7/04 , H04W88/08
CPC分类号： H04L7/048 , H03M13/33 , H04B7/2643 , H04L1/0059 , H04W88/08
摘要： A technique for bit synchronization and error detection of received digital data bursts in a TDM/TDMA system, such as that which will be used with low power portable digital telephony. A cyclically redundant codeword, e.g. a (161,147) codeword, is formed for transmission, using e.g. either a TDM packet or TDMA burst. The first and last bits in the codeword are then inverted to form a first set of marker bits. At a receiver, a second set of marker bits is inserted into a received word, again through inverting the first and last bits. The resulting marked word is then rotated by a pre-determined number of bits to place potentially erroneous bits at the end of this word. A multi-bit timing syndrome value is then determined and is used to access a look-up table for a value of bit slippage. The received word is advanced or retarded as specified by the bit slippage value to yield an intermediate word. The marker bits are removed from the intermediate word to yield an unmarked word for which an error syndrome value is determined. If the error syndrome value is zero, then the unmarked word is a synchronized substantially error-free codeword. If the unmarked word contains excessive bit slippage or bit errors indicated by an excessive value of the timing syndrome or a non-zero valued error syndrome, an indication is provided to ignore this word.
摘要翻译：用于TDM / TDMA系统中接收的数字数据脉冲串的比特同步和错误检测的技术，例如将与低功率便携式数字电话一起使用的技术。循环冗余码字，例如。一个（161,147）码字被形成用于传输，使用例如 TDM分组或TDMA突发。码字中的第一和最后一位然后被反转以形成第一组标记位。在接收机处，通过反转第一位和最后位，再次将第二组标记位插入接收到的字中。然后将得到的标记字旋转预定数量的位，以将潜在的错误位置于该字的末尾。然后确定多位定时综合征值，并且用于访问查询表中的位打滑值。接收到的字是由位滑移值指定的高级或延迟，以产生一个中间字。标记位从中间字移除以产生确定错误校正值的未标记字。如果错误校正值为零，则未标记的字是同步的基本上无错误的码字。如果未标记的字包含由定时综合征的过大值或非零值错误综合征指示的过多的位滑动或位错误，则提供忽略该字的指示。

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