公开(公告)号：US08416729B2

公开(公告)日：2013-04-09

申请号：US12037974

申请日：2008-02-27

申请人： Ernest Sze Yuen Lo ,  Khaled Ben Letaief

发明人： Ernest Sze Yuen Lo ,  Khaled Ben Letaief

IPC分类号： H04B7/14 ,  H04W4/00 ,  H04J3/00 ,  H04B7/185

CPC分类号： H04W72/1257 ,  H04B7/026 ,  H04B7/15542 ,  H04W40/22 ,  H04W88/04 ,  Y02D70/00 ,  Y02D70/1224 ,  Y02D70/1242 ,  Y02D70/39 ,  Y02D70/442 ,  Y02D70/446

摘要： User cooperation is an emerging transmission framework where users act as relays of each other to provide extra diversity paths for better overall performance. In various embodiments, systems and methods for transmitting data from a basestation to a mobile device in an adaptive communications network including user cooperation are provided. Among various embodiments, relaying is performed according to a time division duplex (TDD) system according to either a downlink-assisted relaying (DAR) which performs a relaying operation in a defined supplemental downlink timeslot or according to an uplink-assisted relaying (UAR) which performs a relaying operation in a defined supplemental uplink timeslot. Among other embodiments, relay transmissions according to a max-throughput scheduling algorithm which achieves a maximum system throughput without imposing any fairness constraints on users or according to a round-robin scheduling algorithm which achieves absolute fairness in terms of delays among the considered users. The downlink throughput is optimized from the basestation to the mobile device utilizing either amplify-and-forward (AF) or decode-and-forward (DF) cooperation protocols.

摘要翻译： 用户合作是新兴的传输框架，其中用户作为彼此的中继，以提供额外的分集路径，以获得更好的整体性能。 在各种实施例中，提供了在包括用户协作的自适应通信网络中从基站向移动设备发送数据的系统和方法。 在各种实施例中，根据时分双工（TDD）系统，根据在定义的辅助下行链路时隙中执行中继操作的下行链路辅助中继（DAR）或者根据上行链路辅助中继（UAR）进行中继， 其在定义的补充上行链路时隙中执行中继操作。 在其他实施例中，根据最大吞吐量调度算法的中继传输，其实现最大系统吞吐量，而不对用户施加任何公平约束，或者根据循环调度算法，在所考虑的用户之间的延迟方面实现绝对公平。 使用放大转发（AF）或解码转发（DF）协议协议，从基站到移动设备优化下行链路吞吐量。

公开(公告)号：US20130035133A1

公开(公告)日：2013-02-07

申请号：US13649875

申请日：2012-10-11

申请人： Karama Hamdi ,  Wei Zhang ,  Khaled Ben Letaief

发明人： Karama Hamdi ,  Wei Zhang ,  Khaled Ben Letaief

IPC分类号： H04W52/22 ,  H04W24/00

CPC分类号： H04W52/26 ,  H04W16/14 ,  H04W52/242 ,  H04W52/243 ,  H04W52/246 ,  H04W52/265 ,  H04W52/283 ,  H04W64/00

摘要： For cognitive radio systems, the transmit power of a cognitive radio device is controlled so that the cognitive, unlicensed radio device does not interfere with the use of a shared spectrum by a primary, licensed device. Controlling the transmit power includes determining a distance, or a function of the distance, between a primary transmitter of the primary device and the cognitive radio device based on sensing information from a spectrum sensing process. The maximum transmit power of the cognitive radio device is then dynamically controlled based on the distance, or the function of the distance, while considering a worst case scenario of an underlying cognitive radio model, to guarantee a quality of service requirement of the primary device.

摘要翻译： 对于认知无线电系统，认知无线电设备的发射功率被控制，使得认知的，未许可的无线电设备不会干扰主要许可设备使用共享频谱。 控制发射功率包括基于来自频谱感测过程的感测信息确定主设备的主发射机与认知无线电设备之间的距离或距离的函数。 然后在考虑基础认知无线电模型的最坏情况的情况下，基于距离的距离或距离的函数来动态地控制认知无线电设备的最大发射功率，以保证主设备的服务质量要求。

公开(公告)号：US07965641B2

公开(公告)日：2011-06-21

申请号：US12031521

申请日：2008-02-14

申请人： Khaled Ben Letaief ,  Wei Zhang

发明人： Khaled Ben Letaief ,  Wei Zhang

IPC分类号： G01R31/08

CPC分类号： H04L5/0032 ,  H04B7/026 ,  H04B7/15592 ,  H04L1/0077 ,  H04L1/0606 ,  H04L1/0618 ,  H04L5/0062 ,  H04L5/0091 ,  H04L27/0006 ,  H04W16/14

摘要： The disclosed subject matter relates to communicatively coupled cognitive radio systems, devices, methodologies, or combinations thereof, facilitating improved utilization of unused portions of spectral bands by secondary users generally allocated to other primary users. This improved utilization can be achieved by cooperative spectrum sensing employing ST coding and/or SF coding for transmit diversity. Further, cooperative spectrum sensing can be improved by employing relay diversity with or without algebraic coding. It is illustrated that a threshold probability of false alarm can be reduced by applying transmit diversity with space time coding and/or space frequency coding. It is further illustrated that relay diversity can be employed to compensate for reduced sensing diversity order were some nodes in a cooperative spectrum sensing system cannot report directly. It is disclosed that algebraic coding can be combined with relay diversity to decrease the threshold probability of false alarm in relay diversity systems while maintaining high levels of sensing diversity order.

摘要翻译： 所公开的主题涉及通信耦合的认知无线电系统，设备，方法或其组合，有助于通常分配给其他主要用户的次级用户改进对未使用的频谱带部分的利用。 这种改进的利用率可以通过使用用于发射分集的ST编码和/或SF编码的协作频谱感测来实现。 此外，通过采用具有或不具有代数编码的中继分集，可以提高协作频谱感测。 说明通过应用具有空时编码和/或空间频率编码的发射分集，可以减少误报的阈值概率。 进一步说明，可以采用中继分集来补偿减少的感测分集顺序，即协作频谱感测系统中的一些节点不能直接报告。 公开了代数编码可以与继电器分集组合，以降低继电器分集系统中的误报阈值概率，同时保持高水平的感测分集顺序。

公开(公告)号：US20120238220A1

公开(公告)日：2012-09-20

申请号：US13485538

申请日：2012-05-31

申请人： Ke Lin Du ,  Wai Ho Mow

发明人： Ke Lin Du ,  Wai Ho Mow

IPC分类号： H04B17/00

CPC分类号： H04B17/345

摘要： Spectrum sensing in wireless communications is provided to identify utilized and/or unutilized frequency bands reserved for primary users using a cyclostationary beamforming approach. An adaptive cross self-coherent restoral (ACS) algorithm can be utilized to extract signals of interest (SOI) at unique cycle frequencies related to primary and/or secondary users from an antenna array measurement. Based on the SOI, one or more users of the spectrum can be identified or the spectrum can be regarded as vacant; this can be based on lobe identification in the frequency spectrum of the SOI, in one example. This mechanism is less complex than traditional cyclic spectrum analysis methods. The cyclostationary beamforming based approach is more effective than the energy detection method. Also, the need for quiet periods in spectrum sensing is eliminated when using this mechanism such that signals can be transmitted simultaneously with receiving signals over the antenna array.

公开(公告)号：US08205132B2

公开(公告)日：2012-06-19

申请号：US12105319

申请日：2008-04-18

申请人： Ernest Sze Yuen Lo ,  Khaled Ben Letaief

发明人： Ernest Sze Yuen Lo ,  Khaled Ben Letaief

IPC分类号： G06F11/00

CPC分类号： H03M13/2972 ,  H03M13/2933 ,  H04L1/0059 ,  H04L1/0065 ,  H04L2001/0097

摘要： Cooperative concatenated coding techniques are provided for wireless communications between at least two users and a base station. A network system employing cooperative concatenated coding includes cooperating user devices each configured to encode and transmit at least a portion of a joint message. The joint message includes at least a portion of a first message from a first cooperating user device and at least a portion of a second message from a second cooperating user device. An embodiment includes encoding a first message from a first cooperating user, receiving a second message from a second cooperating user and decoding the second message. The methodology also includes re-encoding at least a portion of the decoded message with at least a portion of the first message to form a combined message, and then transmitting at least a portion of the combined message.

摘要翻译： 提供了用于至少两个用户和基站之间的无线通信的协作级联编码技术。 采用协同级联编码的网络系统包括协作用户设备，每个配置用户设备被配置为对联合消息的至少一部分进行编码和发送。 联合消息包括来自第一协作用户设备的第一消息的至少一部分和来自第二协作用户设备的第二消息的至少一部分。 实施例包括从第一协作用户编码第一消息，从第二协作用户接收第二消息并解码第二消息。 该方法还包括用至少一部分第一消息重新编码解码消息的至少一部分以形成组合消息，然后发送组合消息的至少一部分。

公开(公告)号：US20110312368A1

公开(公告)日：2011-12-22

申请号：US13223120

申请日：2011-08-31

申请人： Karama Hamdi ,  Wei Zhang ,  Khaled Ben Letaief

发明人： Karama Hamdi ,  Wei Zhang ,  Khaled Ben Letaief

IPC分类号： H04W52/04

CPC分类号： H04W52/26 ,  H04W16/14 ,  H04W52/242 ,  H04W52/243 ,  H04W52/246 ,  H04W52/265 ,  H04W52/283 ,  H04W64/00

摘要： For cognitive radio systems, the transmit power of a cognitive radio device is controlled so that the cognitive, unlicensed radio device does not interfere with the use of a shared spectrum by a primary, licensed device. Controlling the transmit power includes determining a distance, or a function of the distance, between a primary transmitter of the primary device and the cognitive radio device based on sensing information from a spectrum sensing process. The maximum transmit power of the cognitive radio device is then dynamically controlled based on the distance, or the function of the distance, while considering a worst case scenario of an underlying cognitive radio model, to guarantee a quality of service requirement of the primary device.

摘要翻译： 对于认知无线电系统，认知无线电设备的发射功率被控制，使得认知的，未许可的无线电设备不会干扰主要许可设备使用共享频谱。 控制发射功率包括基于来自频谱感测过程的感测信息确定主设备的主发射机与认知无线电设备之间的距离或距离的函数。 然后在考虑基础认知无线电模型的最坏情况的情况下，基于距离的距离或距离的函数来动态地控制认知无线电设备的最大发射功率，以保证主设备的服务质量要求。

公开(公告)号：US08542760B2

公开(公告)日：2013-09-24

申请号：US11941293

申请日：2007-11-16

申请人： Wei Zhang ,  Khaled Ben Letaief

发明人： Wei Zhang ,  Khaled Ben Letaief

IPC分类号： H04L5/12

CPC分类号： H04L25/03242 ,  H04B7/15592 ,  H04B7/2606 ,  H04L25/0248 ,  H04L2025/0342 ,  Y02D70/00 ,  Y02D70/446 ,  Y02D70/449

摘要： A full-rate distributed space-time (ST) code design is provided for amplify-and-forward cooperative wireless channels. A signal space diversity technique is employed at the source node and a unique signature vector at each relay node. The distributed space-time (ST) codes can achieve full cooperative diversity and full rate. The achievable diversity gain is M+1, where M is the number of relay nodes. Optimal power allocation can be used to maximize the coding gain under a total power constraint.

摘要翻译： 提供全速率分布式时空（ST）码设计，用于放大和转发协作无线信道。 在源节点采用信号空间分集技术，在每个中继节点采用唯一的签名向量。 分布式时空（ST）码可以实现完全的协同分集和全速率。 可实现的分集增益是M + 1，其中M是中继节点的数量。 最佳功率分配可以用于在总功率约束下最大化编码增益。

公开(公告)号：US20120230230A1

公开(公告)日：2012-09-13

申请号：US13475434

申请日：2012-05-18

申请人： Edward Shunqing Zhang ,  Vincent Kin Nang Lau

发明人： Edward Shunqing Zhang ,  Vincent Kin Nang Lau

IPC分类号： H04B7/14 ,  H04W72/04 ,  H04W40/00

CPC分类号： H04W16/26 ,  H04B7/15592 ,  H04W72/08 ,  H04W84/047 ,  H04W84/08

摘要： A transmission protocol is provided for wireless communications in an OFDMA system that uses a rateless code and techniques are provided for dynamically adjusting the subcarrier resources allocated to an OFDMA relay node so that the relay is used at the right time according to the instantaneous channel state information (CSI). As a result, a higher throughput is achieved between source and destination nodes based on a low complexity algorithm for determining when relay assistance is helpful for completing a transmission between the source and destination nodes.

摘要翻译： 在使用无码代码的OFDMA系统中提供用于无线通信的传输协议，并且提供技术来动态地调整分配给OFDMA中继节点的子载波资源，使得根据瞬时信道状态信息在适当的时间使用中继 （CSI）。 因此，基于用于确定何时中继帮助有助于完成源节点和目的地节点之间的传输的低复杂度算法，在源节点和目的节点之间实现更高的吞吐量。

公开(公告)号：US20120210196A1

公开(公告)日：2012-08-16

申请号：US13455307

申请日：2012-04-25

申请人： Ernest Sze Yuen Lo ,  Khaled Ben Letaief

发明人： Ernest Sze Yuen Lo ,  Khaled Ben Letaief

IPC分类号： H03M13/23 ,  G06F11/10

CPC分类号： H03M13/2972 ,  H03M13/2933 ,  H04L1/0059 ,  H04L1/0065 ,  H04L2001/0097

摘要： Cooperative concatenated coding techniques are provided for wireless communications between at least two users and a base station. A network system employing cooperative concatenated coding includes cooperating user devices each configured to encode and transmit at least a portion of a joint message. The joint message includes at least a portion of a first message from a first cooperating user device and at least a portion of a second message from a second cooperating user device. An embodiment includes encoding a first message from a first cooperating user, receiving a second message from a second cooperating user and decoding the second message. The methodology also includes re-encoding at least a portion of the decoded message with at least a portion of the first message to form a combined message, and then transmitting at least a portion of the combined message.

摘要翻译： 提供了用于至少两个用户和基站之间的无线通信的协作级联编码技术。 采用协同级联编码的网络系统包括协作用户设备，每个配置用户设备被配置为对联合消息的至少一部分进行编码和发送。 联合消息包括来自第一协作用户设备的第一消息的至少一部分和来自第二协作用户设备的第二消息的至少一部分。 实施例包括从第一协作用户编码第一消息，从第二协作用户接收第二消息并解码第二消息。 该方法还包括用至少一部分第一消息重新编码解码消息的至少一部分以形成组合消息，然后发送组合消息的至少一部分。

公开(公告)号：US08213868B2

公开(公告)日：2012-07-03

申请号：US12425754

申请日：2009-04-17

申请人： Ke Lin Du ,  Wai Ho Mow

发明人： Ke Lin Du ,  Wai Ho Mow

IPC分类号： H04B1/00

CPC分类号： H04B17/345

摘要： Spectrum sensing in wireless communications is provided to identify utilized and/or unutilized frequency bands reserved for primary users using a cyclostationary beamforming approach. An adaptive cross self-coherent restoral (ACS) algorithm can be utilized to extract signals of interest (SOI) at unique cycle frequencies related to primary and/or secondary users from an antenna array measurement. Based on the SOI, one or more users of the spectrum can be identified or the spectrum can be regarded as vacant; this can be based on lobe identification in the frequency spectrum of the SOI, in one example. This mechanism is less complex than traditional cyclic spectrum analysis methods. The cyclostationary beamforming based approach is more effective than the energy detection method. Also, the need for quiet periods in spectrum sensing is eliminated when using this mechanism such that signals can be transmitted simultaneously with receiving signals over the antenna array.

摘要翻译： 提供无线通信中的频谱感测以使用循环平稳波束成形方法来识别为初级用户保留的利用和/或未被使用的频带。 可以利用自适应交叉自相干恢复（ACS）算法从天线阵列测量中以与主用户和/或次要用户相关的独特周期频率提取感兴趣的信号（SOI）。 基于SOI，可以识别光谱的一个或多个用户，或者可以将光谱视为空白; 这可以基于SOI的频谱中的叶片识别，在一个示例中。 这种机制比传统的循环谱分析方法不复杂。 基于循环平稳波束成形的方法比能量检测方法更有效。 此外，当使用这种机制时，消除了在频谱感测中的安静周期的需要，使得可以通过天线阵列与接收信号同时传输信号。