一种基于码本聚类的低复杂度用户选择算法

现有块对角化(BD)预编码系统用户选择算法较少考虑利用已选用户与剩余用户之间的关系来排除不可选用户.针对这点不足,给出了一种采用码本聚类的低复杂度用户选择算法( CodeGreedy算法).该算法采用弦距离刻画用户信道的相关性,以此为依据将用户划分到不同码本空间中,聚集在同一码本空间的用户信道具有较强的相关性,形成互斥...     

ADS5287及其在MIMO接收机中的应用

介绍了TI公司模数转换器ADS5287的性能特点.用ADS5287作为模数转换器设计了MIMO中频接收机电路,完成了系统的PCB设计,并使用Hyperlynx软件中的Boradsim工具对设计中重要的高速信号线做了信号完整分析.     

Scaling Kernel-Based Systems to Large Data Sets

In the form of the support vector machine and Gaussian processes, kernel-based systems are currently very popular approaches to supervised learning. Unfortunately, the computational load for training kernel-based systems increases drastically with the size of the training data set, such that these systems are not ideal candidates for applications with large data sets. Nevertheless, research in this direction is very active. In this paper, I review some of the current approaches toward scaling kernel-based systems to large data sets.     

A SAT Solver Using Reconfigurable Hardware and Virtual Logic

In this paper, we present the architecture of a new SAT solver using reconfigurable logic and a virtual logic scheme. Our main contributions include new forms of massive fine-grain parallelism, structured design techniques based on iterative logic arrays that reduce compilation times from hours to minutes, and a decomposition technique that creates independent subproblems that may be concurrently solved by unconnected FPGAs. The decomposition technique is the basis of the virtual logic scheme, since it allows solving problems that exceed the hardware capacity. Our architecture is easily scalable. Our results show several orders of magnitude speedup compared with a state-of-the-art software implementation, and also with respect to prior SAT solvers using reconfigurable hardware.     

一种多变量系统分散优化DMC算法

提出一种多变量系统的分散优化动态矩阵控制（ＤＭＣ）算法,该处冯动 经的特点,将多变量系统ＤＭＣ算法分散为若干单变量系统的ＤＭＣ算法,使多变量ＤＭＣ算法参数设计和算法求解计算人为简化。     

结合机会调度和迫零接收机的SM．rvnMo系统研究

为了充分利用多用户MIMO系统中固有的多用户分集,采用机会调度方案,根据接收端反馈的信道 状态信息选择有着最大信噪比的用户进行数据传输,同时为了有效地利用复用增益,提高系统的容量,在平 坦瑞利信道中,提出并分析了结合机会调度和空间复用的采用迫零接收机的MIMO系统方案．在不同信道估 计下,根据基于多项式展开的方法,分别推导出了采用M-QAM和M-PSK调制的系统的误码率、分集增益量 化值以及总速率容量,并用基于泰勒级数的方法对其进行渐近分析．通过蒙塔卡罗仿真很好地验证了理论分 析的正确性,表明该方案相对于没有机会调度的系统提供了更大的分集和更高的容量     

彩色图像增强的改进算法

为提高彩色图像的整体感官效果,在研究CES（Color image Enhancement by Scaling）算法出现块效应的原因基础上,提出了一种改进算法,即各向异性扩散滤波器的ICES（Improved Color image Enhancement byScaling）。与CES相比,ICES算法在不增加计算复杂性的前提下,不仅得到了不逊于CES算法的增强效果,还能极大地抑制块效应。     

密集阵MIMO雷达阵列模式及其特性

为了对密集阵MIMO雷达不同阵列模式之间的联系进行研究,建立了密集阵MIMO雷达多次快拍信号模型,导出了接收信号相位历史的解析表达式,并通过相位历史表达式揭示了其蕴含的三种阵列模式以及生成机理;结合各阵列模式形成机理分别讨论了三种不同模式阵列特性.最后通过仿真结果对各阵列模式的特性进行了分析.研究结果表明,密集阵MIMO雷达不同阵列模式可带来不同的得益.     

MIMO-OFDM系统信道估计器的导频间隔优化设计

研究了导频子载波方式下,信道相干带宽、多普勒频移和信噪比对信道估计器的最优导频间隔设计的影响,以确定最优导频间隔。实验结果表明,要达到相同误码率性能,相干带宽越小的信道对应的信道估计器所需的最小导频间隔越小,而且在信道信噪比较低时,误码率不随导频间隔增加而线性增加,因此存在不为最小值的最优导频间隔。导频子载波方式适用于高速移动通信的最佳导频位置方式。     

Interactive Ray Tracing of Large Models Using Voxel Hierarchies

We propose an efficient approach for interactive visualization of massive models with CPU ray tracing. A voxel‐based hierarchical level‐of‐detail (LOD) framework is employed to minimize rendering time and required system memory. In a pre‐processing phase, a compressed out‐of‐core data structure is constructed, which contains the original primitives of the model and the LOD voxels, organized into a kd‐tree. During rendering, data is loaded asynchronously to ensure a smooth inspection of the model regardless of the available I/O bandwidth. With our technique, we are able to explore data sets consisting of hundreds of millions of triangles in real‐time on a desktop PC with a quad‐core CPU.