为了降低空频分组编码的多输入多输出正交频分复用(Space Frequency Block Coding Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing,SFBC MIMO-OFDM)系统中传统选择性映射(Selected Mapping,SLM)算法的计...为了降低空频分组编码的多输入多输出正交频分复用(Space Frequency Block Coding Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing,SFBC MIMO-OFDM)系统中传统选择性映射(Selected Mapping,SLM)算法的计算复杂度,本文提出了结合时域信号的循环移位和等效SFBC编码来产生更多具有不同峰均功率比(Peak to Average Power Ratio,PAPR)的备选序列的方法.接收端通过比较反向旋转序列与最近星座点的距离来恢复出循环移位因子和相位旋转因子,从而实现接收信号的盲检测.仿真结果表明,本文提出方法能有效地抑制SFBC MIMO-OFDM系统的PAPR.另外,本文提出方法明显降低了传统SLM算法的计算复杂度,而且可以获得与传统SLM算法在已知边带副信息情况下相似的比特误码率(Bit Error Rate,BER)性能.展开更多
An adaptive inverse controller for nonliear discrete-time system is proposed in this paper. A compound neural network is constructed to identify the nonlinear system, which includes a linear part to approximate the no...An adaptive inverse controller for nonliear discrete-time system is proposed in this paper. A compound neural network is constructed to identify the nonlinear system, which includes a linear part to approximate the nonlinear system and a recurrent neural network to minimize the difference between the linear model and the real nonlinear system. Because the current control input is not included in the input vector of recurrent neural network (RNN), the inverse control law can be calculated directly. This scheme can be used in real-time nonlinear single-input single-output (SISO) and multi-input multi-output (MIMO) system control with less computation work. Simulation studies have shown that this scheme is simple and affects good control accuracy and robustness.展开更多
To avoid the exhaustive search, we propose a fast user selection algorithm for Signal-to-Interference-plus-Noise-Ratio (SINR)-based multiuser Multiple-Input Multiple-Output (MIMO) systems with Alamouti Space-Time Bloc...To avoid the exhaustive search, we propose a fast user selection algorithm for Signal-to-Interference-plus-Noise-Ratio (SINR)-based multiuser Multiple-Input Multiple-Output (MIMO) systems with Alamouti Space-Time Block Code (STBC) transmit scheme. A locally optimal selection criterion is proposed at first. Then, the incremental selection approach is applied, which selects one among the residual available users to maximize the minimum user SINR step by step. Simulation results show that the fast algorithm gains over 90% of the diversity benefit achieved by the exhaustive search selection, and that the fast algorithm has much lower computational burden than the exhaustive search one, for the scenario where the number of all the available users is much greater than that of the selected users.展开更多
文摘为了降低空频分组编码的多输入多输出正交频分复用(Space Frequency Block Coding Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing,SFBC MIMO-OFDM)系统中传统选择性映射(Selected Mapping,SLM)算法的计算复杂度,本文提出了结合时域信号的循环移位和等效SFBC编码来产生更多具有不同峰均功率比(Peak to Average Power Ratio,PAPR)的备选序列的方法.接收端通过比较反向旋转序列与最近星座点的距离来恢复出循环移位因子和相位旋转因子,从而实现接收信号的盲检测.仿真结果表明,本文提出方法能有效地抑制SFBC MIMO-OFDM系统的PAPR.另外,本文提出方法明显降低了传统SLM算法的计算复杂度,而且可以获得与传统SLM算法在已知边带副信息情况下相似的比特误码率(Bit Error Rate,BER)性能.
基金Supported by the National Natural Science Foundation of China (60575009, 60574036)
文摘An adaptive inverse controller for nonliear discrete-time system is proposed in this paper. A compound neural network is constructed to identify the nonlinear system, which includes a linear part to approximate the nonlinear system and a recurrent neural network to minimize the difference between the linear model and the real nonlinear system. Because the current control input is not included in the input vector of recurrent neural network (RNN), the inverse control law can be calculated directly. This scheme can be used in real-time nonlinear single-input single-output (SISO) and multi-input multi-output (MIMO) system control with less computation work. Simulation studies have shown that this scheme is simple and affects good control accuracy and robustness.
文摘To avoid the exhaustive search, we propose a fast user selection algorithm for Signal-to-Interference-plus-Noise-Ratio (SINR)-based multiuser Multiple-Input Multiple-Output (MIMO) systems with Alamouti Space-Time Block Code (STBC) transmit scheme. A locally optimal selection criterion is proposed at first. Then, the incremental selection approach is applied, which selects one among the residual available users to maximize the minimum user SINR step by step. Simulation results show that the fast algorithm gains over 90% of the diversity benefit achieved by the exhaustive search selection, and that the fast algorithm has much lower computational burden than the exhaustive search one, for the scenario where the number of all the available users is much greater than that of the selected users.
