摘要：This paper proposes a joint nonlinear transceiver design scheme based on minimum mean square error （mmse） criterion for non-regenerative multiple input multiple output （MIMO） relay system. The proposed scheme decomposes the error covariance matrix, reformulates the original joint design problem as two separate optimization problems, and then provides a closed-form solution with only local channel state information （CSI） available at the source and destination. Performance evaluation shows that the proposed scheme significantly outperforms linear schemes, and has a competitive performance compared with existing global CSI based nonlinear schemes, both iterative and non-iterative.

摘要：共振解调作为滚动轴承常用的故障诊断方法,存在带通滤波器参数难以确定的缺点,针对此缺点以及滚动轴承早期故障信号信噪比低的问题,结合最小均方误差估计方法(mmse)和基于谱峭度的共振解调方法,并将其应用于滚动轴承早期微弱故障诊断中。首先用mmse方法抑制白噪声来提高信噪比,然后利用谱峭度自适应确定最优带通滤波器参数,最后对带通滤波后的信号进行能量算子解调谱分析,得出诊断结果。数字仿真信号和实验信号验证了该方法的有效性。

摘要：分析比较了多种子空间跟踪算法.复杂度高的特征值分解和奇异值分解不利于工程实现,而低复杂度的PASTd应用于多用户检测导致收敛速度慢并且检测性能差.介绍了SP子空间跟踪算法,利用SP算法跟踪信号子空间求得解调向量,设计了修正的mmse检测器.与SVDMUD和PASTd MUD两种算法相比,仿真结果显示SP MUD算法收敛速度快,输出信噪比和误码率性能接近SVD MUD算法,并保持了较低的计算复杂度,是一种较好的实现方案.

摘要：在研究基于子空间跟踪的最小均方误差(mmse)多用户检测器(MUD)的基础上,为解决原算法因引入特征值估计误差而导致检测性能下降的问题,设计了一种改进的算法———修正的mmse多用户检测器.采用正交性能优良的OPAST算法跟踪子空间,提出一种基于OPAST的修正mmse多用户检测算法.仿真结果显示,与基于OPAST的mmse MUD相比,基于OPAST的修正mmse MUD算法收敛速度快,输出信干比和误码率性能逼近SVD MUD算法,并且计算复杂度较低.

摘要：智能天线中一般的mmse接收机缺乏有效跟踪Rayleigh衰落信道变化的机制。在分析了mmse接收机在Rayleigh信道中的特点之后 ,提出一种新型的CDMA系统mmse接收机。计算机仿真结果表明 ,此接收机性能较好 ,适用于Rayleigh衰落信道。

摘要：自适应OFDM(Orthogonal Frequency Division Multiplexing)系统根据信道情况自适应地分配各个子载波发送的比特和功率,在频率选择性衰落信道条件下,它比传统的OFDM系统有更好的误比特性能。提出了一种基于mmse准则的自适应预处理算法,并将该算法应用于自适应OFDM系统,与基于最大信息速率设计的自适应OFDM系统相比,误比特性能有了显著提高。

摘要：上行链路的大规模多入多出(MIMO)系统信号检测中,最小均方误差(mmse)算法由于涉及矩阵求逆运算使得算法复杂度过高。为改善这一缺点,在传统mmse算法的基础上,通过设计一种新的迭代方式代替矩阵求逆,使原算法的复杂度降低了一个数量级。理论分析及仿真表明,改进算法显著改善了传统mmse算法的复杂度,仅需少量迭代次数就能快速向理想mmse矩阵求逆检测算法收敛。

摘要：In this paper, we study an innovative multiple access scheme that exploits the intrinsic properties of the wireless envi- ronment to improve the multiuser environment, so-called Channel Division Multiple Access (ChDMA) focusing on spectral efficiency analysis and system performance. In particular, we show that Simultaneous multiuser accessing to a common destination is made possible by considering the channel impulse response (CIR) of each user as a signature. We begin by the assumption of the channel state information available at the receiver. Then, we analyze the perform- ance of the ChDMA integration in a random environment over UWB high data rate channel. Next, we discuss the de- sign of mmse and optimal receiver structure for such a system. Additionally, we show an asymptotic analysis behavior taking into account the channel eigenvalues distribution with the associated spectral efficiency.

摘要：Recently, multiple-input multiple-output (MIMO) relay technique has been received great attention due to its prominent ability to provide broad coverage and enhance the link reliability and spectral efficiency. In this paper, an overview of optimal design for single user and multiuser non-regenerative MIMO relay systems is proposed. We explore some key designs of source node and destination node as well as relay node processing matrices using minimum mean square error (mmse) criterion under the transmit power constraints. Simulation results compare different methods in terms of the MSE and bit error rate (BER) performance.