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1.发明授权Soft handover system for a multiple sub-carrier communication system and method thereof 失效一种多子载波通信系统的软切换系统及其方法
公开(公告)号：US6038450A
公开(公告)日：2000-03-14
申请号：US928307
申请日：1997-09-12
CPC分类号： H04L27/2626 , H04B7/022 , H04L27/2647 , H04W36/18
摘要： A soft handover system is provided for a multiple sub-carrier communication system, applicable to the uplink (mobile unit to base stations) and/or the downlink (base stations to mobile unit). The soft handover system uses multiple sub-carriers to simultaneously transmit multiple sub-carrier signals between at least two base stations and the mobile unit in the uplink and/or downlink. In certain embodiments, the soft handover system provides for synchronized multiple sub-carrier transmission such that the delay differences between the multiple sub-carrier transmissions from the different base stations arriving at the mobile unit are within the guard time of the multiple sub-carrier symbols. Certain embodiments of the soft handover system use the same set of sub-carriers for links between the mobile unit and the base stations of different cells, and other embodiments use different sets of sub-carriers for links between the mobile unit and the base stations of different cells. In the soft handover system using the same set of sub-carriers, the mobile unit receives downlink signals with identical data content from the different base stations. The mobile unit need not distinguish between the signals from the different base stations. The mobile unit just treats the downlink signals from the different base stations as multipath components, thereby increasing the diversity gain. In the case of a multiple sub-carrier CDMA system, the soft handover system can use the same sub-carriers as well as the same CDMA encoding and/or spreading code.
摘要翻译： 为适用于上行链路（移动单元到基站）和/或下行链路（基站到移动单元）的多子载波通信系统提供软切换系统。 软切换系统使用多个子载波在上行链路和/或下行链路中在至少两个基站与移动单元之间同时发送多个子载波信号。 在某些实施例中，软切换系统提供同步的多载波传输，使得来自到达移动单元的不同基站的多个子载波传输之间的延迟差在多个子载波符号的保护时间之内 。 软切换系统的某些实施例对移动单元和不同小区的基站之间的链路使用相同的子载波集合，并且其他实施例对移动单元和基站之间的链路使用不同的子载波集合 不同的细胞。 在使用同一组子载波的软切换系统中，移动单元从不同的基站接收具有相同数据内容的下行链路信号。 移动单元不需要区分来自不同基站的信号。 移动单元仅将来自不同基站的下行链路信号视为多径分量，从而增加分集增益。 在多子载波CDMA系统的情况下，软切换系统可以使用相同的子载波以及相同的CDMA编码和/或扩展码。
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公开(公告)号：US07079567B2
公开(公告)日：2006-07-18
申请号：US10207474
申请日：2002-07-29
CPC分类号： H04L23/02 , H04J13/0048 , H04J13/10 , H04L27/2602 , H04L27/2617 , H04L27/2621
摘要： A digital (de)modulation system uses a larger code set of M codes for N length codes, where M>N, to provide an increased data rate while maintaining the coding gain. For example, the system can use 16 different codes each having a length of 11 chips in a code set while the conventional M-ary keying systems use a code set size of 8 for 11-chip codes or 8-chip codes. By extending the code set size, the system increases the data rate of the system. With 16 codes and the ability to change the sign of the code to be transmitted, the system can encode 5 data bits on both I and Q, so a total of 10 data bits can be encoded per code symbol. In this embodiment, a code symbol contains an 11 chip code on a I modulation branch and an 11 chip code on a Q modulation branch. As such, using 11 chip codes and a chip rate of 11 Mhz, the system provides a data rate of 10 Mbps while conventional M-ary keying systems can only achieve 8 Mbps using the same code length and chip rate. By extending the code length, the processing gain is increased. The extended code set is not orthogonal, so a non-zero cross-correlation value results between the different codes of the code set. However, the resulting noise and multipath performance degradation can be kept small by choosing code sets with small cross-correlation values (nearly orthogonal). The magnitudes of both cross-correlation values and auto-correlation sidelobes should preferably be below half a code length. In some embodiments, the code set is derived from orthogonal codes which are modified to reduce the autocorrelation sidelobes associated with the orthogonal codes. In other embodiments, the code set is derived using a complementary code which provides low autocorrelation sidelobes and is modified to reduce the cross-correlation values between the codes.
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公开(公告)号：US06452958B1
公开(公告)日：2002-09-17
申请号：US09064188
申请日：1998-04-22
IPC分类号： H04B169
CPC分类号： H04L23/02 , H04J13/0048 , H04J13/10 , H04L27/2602 , H04L27/2617 , H04L27/2621
摘要： A digital (de)modulation system uses a larger code set of M codes for N length codes, where M>N, to provide an increased data rate while maintaining the coding gain. For example, the system can use 16 different codes each having a length of 11 chips in a code set while the conventional M-ary keying systems use a code set size of 8 for 11-chip codes or 8-chip codes. By extending the code set size, the system increases the data rate of the system. With 16 codes and the ability to change the sign of the code to be transmitted, the system can encode 5 data bits on both I and Q, so a total of 10 data bits can be encoded per code symbol. In this embodiment, a code symbol contains an 11 chip code on a I modulation branch and an 11 chip code on a Q modulation branch. As such, using 11 chip codes and a chip rate of 11 Mhz, the system provides a data rate of 10 Mbps while conventional M-ary keying systems can only achieve 8 Mbps using the same code length and chip rate. By extending the code length, the processing gain is increased. The extended code set is not orthogonal, so a non-zero cross-correlation value results between the different codes of the code set. However, the resulting noise and multipath performance degradation can be kept small by choosing code sets with small cross-correlation values (nearly orthogonal). The magnitudes of both cross-correlation values and auto-correlation sidelobes should preferably be below half a code length. In some embodiments, the code set is derived from orthogonal codes which are modified to reduce the autocorrelation sidelobes associated with the orthogonal codes. In other embodiments, the code set is derived using a complementary code which provides low autocorrelation sidelobes and is modified to reduce the cross-correlation values between the codes.
摘要翻译： 数字（de）调制系统对于N个长度代码使用M代码的较大代码集合，其中M> N，以在保持编码增益的同时提供增加的数据速率。 例如，系统可以使用16个不同的代码，每个代码在代码集中具有长度为11个的芯片，而常规的M元键控系统对于11个芯片代码或8个芯片代码使用8的代码集大小。 通过扩展代码集大小，系统增加了系统的数据速率。 利用16个代码和改变要发送的代码的符号的能力，系统可以对I和Q两者编码5个数据位，因此可以对每个代码符号编码总共10个数据位。 在本实施例中，代码符号在I调制分支上包含11个码片码，在Q调制分支上包含11个码片码。 因此，使用11芯片代码和11 Mhz的芯片速率，系统提供10 Mbps的数据速率，而传统的M系统键控系统只能使用相同的码长和码片速率实现8 Mbps。 通过扩展代码长度，处理增益增加。 扩展代码集不正交，因此在代码集的不同代码之间产生非零互相关值。 然而，通过选择具有小互相关值（几乎正交）的代码集，可以将所得到的噪声和多径性能降级保持较小。 互相关值和自相关旁瓣的大小应优选低于码长的一半。 在一些实施例中，代码集从正交码导出，其被修改以减少与正交码相关联的自相关旁瓣。 在其他实施例中，使用提供低自相关旁瓣并且被修改以减少代码之间的互相关值的互补码导出代码集。
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公开(公告)号：US6160510A
公开(公告)日：2000-12-12
申请号：US887856
申请日：1997-07-03
CPC分类号： H01Q3/2682 , H01Q3/2605 , H04B7/0828 , H04B7/084
摘要： An antenna array system combines the antenna signals from separate antennas using at least one delay in the RF path of an antenna. In certain embodiments, the antenna array system combines the antenna signals in the Radio Frequency (RF) domain before analog-to-digital (A/D) conversion, thereby reducing the amount of hardware required when compared to antenna array systems where the antenna signals are combined digitally. In doing so, signals from antennas are combined with signals from a plurality of antennas to determine if they improve signal quality. Only signals determined to improve signal quality are maintained as active. In accordance with other aspects, the antenna system selects parameter settings for the antenna array to provide enhanced performance.
摘要翻译： 天线阵列系统使用天线的RF路径中的至少一个延迟来组合来自不同天线的天线信号。 在某些实施例中，天线阵列系统将模拟 - 数字（A / D）转换之前的射频（RF）域中的天线信号组合在一起，从而与天线阵列系统相比，减少了所需的硬件量 数字组合。 在这样做时，来自天线的信号与来自多个天线的信号组合以确定它们是否改善信号质量。 只有确定提高信号质量的信号才能保持活跃。 根据其他方面，天线系统选择天线阵列的参数设置以提供增强的性能。
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公开(公告)号：US07127013B2
公开(公告)日：2006-10-24
申请号：US10643155
申请日：2003-08-18
IPC分类号： H04L1/02
CPC分类号： H04B1/7093 , H04B7/0851 , H04B7/0854 , H04L25/03267
摘要： A wireless receiver receives signals at a plurality of antennas and the combined signal is compensated for channel distortion. In other aspects, a wireless receiver includes a minimum distance receiver applied to the output of a whitened-matched filter, which combines channel matched filtering and whitening, using one or more antennas.
摘要翻译： 无线接收机在多个天线处接收信号，并且对信道失真进行补偿。 在其他方面，无线接收机包括使用一个或多个天线来应用于白化匹配滤波器的输出的最小距离接收机，其组合信道匹配滤波和白化。
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6.发明授权公开(公告)号：US06175550B1
公开(公告)日：2001-01-16
申请号：US08834684
申请日：1997-04-01
IPC分类号： H04J1100
CPC分类号： H04L27/2614 , H04L1/0002 , H04L1/0003 , H04L1/0007 , H04L1/0009 , H04L1/0025 , H04L5/0007 , H04L5/0044 , H04L5/006
摘要： The scaleable OFDM system according to the principles of the present invention provides increased flexibility and adaptability by providing scaling of the operating parameters and/or characteristics for the OFDM system. For example, control circuitry can scale the bit rate by scaling of the OFDM symbol duration, the number of carriers and/or the number of bits per symbol per carrier. Scaleability permits the scaleable OFDM system to operate in various communications environments requiring various operating parameters and/or characteristics. By scaling the operating parameters and/or characteristics of the OFDM system when control circuitry determines that different operating parameters and/or characteristics are necessary or advantageous, the control circuitry can dynamically change the operating parameters and/or characteristics, thereby providing compatibility or the desired performance. For example, by dynamically scaling the bit rate, widely varying signal bandwidths, delay spread tolerances and signal-to-noise ratio (SNR) requirements can be achieved. As such, a scaleable OFDM system is particularly suitable for application in mobile, wireless communication devices, which support a variety of services, in a variety of environments, indoor as well as outdoor and in radio channels with differing bandwidths.
摘要翻译： 根据本发明的原理的可扩展OFDM系统通过提供OFDM系统的操作参数和/或特性的缩放来提供增加的灵活性和适应性。 例如，控制电路可以通过缩放OFDM符号持续时间，载波数量和/或每个载波每个符号的比特数来缩放比特率。 可扩展性允许可扩展OFDM系统在需要各种操作参数和/或特性的各种通信环境中操作。 当控制电路确定不同的操作参数和/或特性是必需或有利时，通过缩放OFDM系统的操作参数和/或特性，控制电路可以动态地改变操作参数和/或特性，由此提供兼容性或期望的 性能。 例如，通过动态地缩放比特率，可以实现广泛变化的信号带宽，延迟扩展容限和信噪比（SNR）要求。 因此，可扩展的OFDM系统特别适合于在各种环境中，在室内以及室外以及具有不同带宽的无线电信道中支持各种服务的移动无线通信设备中的应用。
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7.发明授权
公开(公告)号：US6005840A
公开(公告)日：1999-12-21
申请号：US834667
申请日：1997-04-01
CPC分类号： H04L27/2628 , H04L27/2617
摘要： The combined complementary encoder and modulation system for an OFDM transmitter system combines complementary coding and modulation and exploits the similarity of their mathematical structure to reduce implementation complexity. In doing so, the improved OFDM transmitter system uses complementary codes to reduce the power-to-average power (PAP) ratio of the transmitted signal. Additionally, the combined complementary encoder and modulation system can be modified to provide scaleablity, which allows a transmitter to operate in various transmission environments. More precisely, scaleability refers to the transmitter's capability to adapt the bit rate of the data, so as to satisfy varying signal bandwidth, delay spreads, tolerance and signal-to-noise ratio requirements.
摘要翻译： 用于OFDM发射机系统的组合的互补编码器和调制系统结合了互补编码和调制，并利用其数学结构的相似性来降低实现复杂度。 在这样做时，改进的OFDM发射机系统使用互补码来降低发射信号的功率 - 平均功率（PAP）比。 另外，组合的互补编码器和调制系统可以被修改以提供可扩展性，其允许发射机在各种传输环境中操作。 更准确地说，可扩展性是指发射机适应数据比特率的能力，以满足变化的信号带宽，延迟扩展，公差和信噪比要求。
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