Performance analysis for V‐BLAST system using OSIC receiver in correlated channel

Vertical‐Bell Labs Layered Space–Time (V‐BLAST) system is an emerging spatial multiplexing scheme that can achieve high spectral efficiency. Ordered successive interference cancellation (OSIC) detection algorithm is suitable for V‐BLAST system because it can afford a reasonable trade‐off between complexity and performance. However, the correlation of a real‐world wireless channel may result in a substantial degradation of the OSIC performance. In this paper, the performance of OSIC under correlated fading is analyzed. We obtain the closed‐form expression of post‐processing signal‐to‐noise ratio (SNR) for each sub‐stream based on V‐BLAST architecture, and then derive the distribution of post‐processing SNR based on multivariate statistical theory. The upper bound of the average probability of error (APE) is derived by the nearest neighbor union bound theory. From the expression of APE for each sub‐stream, it is shown that the diversity gain at the ith processing step is (N ? M + i), where N and M are the number of receive and transmit antennas, respectively. Correlation can decrease the effective post‐processing SNR rather than the diversity gain, and the decreased amount of the effective post‐processing SNR is accurately measured by the corresponding diagonal element of the inverse of the transmit correlation matrix. The optimal ordering can improve the performance and this advantage vanishes gradually as the scattering angle decreases. Copyright © 2010 John Wiley & Sons, Ltd.     

基于Turbo码的MIMO?OFDM检测系统的研究与设计

在MIMO?OFDM系统中,分层空时编码技术可以有效地提高空间复用增益,但是由于其译码层是相互独立的,因此系统编码增益并不高,而基于迭代法译码的Turbo码具有良好的编码增益,因此,提出采用联合分层空时编码技术和Turbo迭代解码原理的MIMO?OFDM检测系统,通过仿真实验验证,该系统不仅可以提高MIMO?OFDM系统的性能,在频率选择性衰落信道下该系统也具有良好的可靠性。     

V-BLAST系统中的迭代软判决干扰抵消检测算法

分层空时结构(BLAST)是一种通过使用多根发射天线和接收天线,以及在接收端使用先进的信号处理技术来获得高频谱效率的技术。主要研究了基于MMSE的迭代软判决干扰抵消(ISDIC)算法在V BLAST系统中的应用。仿真结果表明,相对于传统的检测算法,其性能至少有1 dB的增益。     

软岩帮坡中预裂爆破参数的探讨

结合矿山实际，在理论和实践上对软岩帮坡中的预裂爆破参数进行探讨，推荐出一套适合软岩帮坡的预裂爆破参数。     

多入多出(MIMO)分层空时码算法研究

概述了一种新的编码和信号处理技术—分层空时码(BLAST)的编解码算法,并比较了各自的优缺点。由于D-BLST的计算复杂度太大,重点分析了工程上具有实用价值的V-BLAST算法,文章的最后给出了仿真结果和结论。     

Control of open slag bath furnaces at Highveld Steel and Vanadium Ltd: development of operator guidance tables

Abstract

Several electric furnaces, which are used to melt down partially prereduced vanadiferous magnetite at Highveld Steel and Vanadium, have recently been converted from submerged arc furnaces (SAFs) to open slag bath furnaces (OSBFs). The self-regulating nature of SAFs is largely absent from the OSBFs, and hence the OSBFs rely more strongly on process control. As a first step towards implementing a process control system, a mass and energy balance was drawn up for the OSBFs, and this was used to develop operator guidance tables. The tables show the required changes in feed rate and power, to accommodate changes in prereduction, and to correct overcharged and undercharged furnace conditions. Implementation of the tables has contributed to improved process stability.     

A coprocessor architecture for fast protein structure prediction

Predicting the protein structure from an amino acid sequence is computationally very intensive. In order to speed up protein sequence matching and processing, we present a novel coprocessor architecture for fast protein structure prediction. The architecture consists of systolic arrays to speed up the data intensive sequence alignment and structure prediction steps, and finite state machines for the control dominated steps. The architecture has been synthesized using Synopsys DC Compiler in 0.18 micron CMOS technology and details of its area and timing performance have been provided. A procedure to develop architectures with area-time trade-offs has also been presented.     

A VLSI Architecture of the Square Root Algorithm for V-BLAST Detection

MIMO has been proposed as an extension to 3G and Wireless LANs. As an implementation scheme of MIMO systems, V-BLAST is suitable for the applications with very high data rates. The square root algorithm for V-BLAST detection is attractive to hardware implementations due to its low computational complexity and numerical stability. In this paper, the fixed-point implementation of the square root algorithm is analyzed, and a low complexity VLSI architecture is proposed. The proposed architecture is scalable for various configurations, and implemented for a 4 × 4 QPSK V-BLAST system in a 0.35 m CMOS technology. The chip core covers 9 and 190 K gates. The detection throughput of the chip depends on the received symbol packet length. When the packet length is larger than or equal to 100 bytes, it can achieve a maximal detection throughput of 128 160 Mb/s at a maximal clock frequency of 80 MHz. The core power consumption, measured at 2.7 V and room temperature, is about 608 mW for 160 Mb/s data rate at 80 MHz, and 81 mW for 20 Mb/s at 10 MHz. The proposed architecture is shown to meet the requirements for emerging MIMO applications, such as 3G HSDPA and IEEE 802.11n.     

基于阿拉莫提模型的BLAST与STBC结合算法

提出了一种基于2×2天线阵列的BLAST与STBC的结合算法,在初始传输的时候使用BLAST来提高系统容量,如果出错则重传的信号和初始信号结合为STBC来获得高的分集增益.该算法相对于BALST算法有更低的误码率,相对于STBC算法有更高的传输速率,因此具有良好的性能和优越的鲁棒性.仿真结果证明,通过少量的额外带宽为代价换取了性能的很大提升.