智能配电网与配电自动化

随着居民的生活质量的进步,居民对电力的要求也在提升,但是国家的传统配电网程度低,构架薄弱,以及配电自动化未能广泛应用,依旧处在初级阶段,不再适用于当今社会,为了满足我国的工业用电、居民用电的要求,许多的电力企业渐渐的把注意力转移到了智能配电网上,这种智能配电网提高了电力系统的整体水平.     

混沌跳频通信的非线性自适应预测对抗

基于混沌跳频码序列构造固有的确定性、非线性等特点,提出了对抗混沌跳频通信的非线性自适应预测对抗的新概念.以Logistic-Kent映射设计的混沌跳频码为例,采用基于Sigmiod函数的Volterre自适应滤波预测器对其进行预测研究.仿真实验结果表明非线性自适应预测器比神经网络预测器具有更高的预测对抗效果.     

双包层光纤放大器研究

双包层光纤放大器输出功率高,可用于密集波分复用系统、光纤CATV系统以及空间光通信系统中。本文采用分段方法,利用光子数平衡原理建立了半数值双包层掺稀土光纤放大器理论模型。利用本模型可以对双包层光纤放大器进行优化设计。     

A few CMOS transconductors optimized for low power and wide band operation

Maximizing the bandwidth of operation relative to dc power dissipation in complementary metal oxide semiconductor (CMOS) transconductors has been addressed in this article. It is proposed that the ac transconductance-to-dc power dissipation ratio is an appropriate objective function in this case. The general nature of the objective function is examined first. CMOS transconductors with two and four MOS working transistors are analyzed next. For structures of each kind, the ac transconductance-to-dc power dissipation ratio is maximized, and the optimal set of voltage variables is evaluated. For four-MOS structures with differential input signals, it is revealed that the choice of signal phase influences the objective function. The results of theoretical analyses are exhaustively tabulated. Numerical simulations are used to bring out the significance of the analytical expressions. This facilitates a comparison among several transconductors regarding the best possible ac transconductance-to-dc power dissipation ratio. These results are combined with HSPICE simulation results to suggest a few transconductor structures that are optimum with reference to the operation over wide bandwidths with lower power dissipation, high linearity and low harmonic distortion.The research was supported by grant no. N485 awarded to Dr. R. Raut by the Natural Science and Engineering Research Council (NSERC) of Canada.     

An effective multiuser receiver for DS/CDMA systems

Multiuser detection (MUD) is a key technique for combating multiple access interference (MAI) in CDMA systems. We propose a simple and effective multiuser receiver, which we refer to as the objective function based multiuser detector (OFMUD). This is a successive multistage joint detector based on the statistical optimization of an objective function. Two objective functions are considered in this paper. The first one is based on a maximum likelihood solution, and the second one is based on the least squared error solution. A key feature of the proposed detector is that among all the K user bits, we update the estimate of one and only one bit (the one that is most likely to be wrong) in every stage. Analytical and numerical results show that significant performance improvement can be achieved compared with the conventional DS/CDMA receiver. At the same time, the near-far problem is alleviated. In addition, it is shown that the proposed receiver can outperform the popular multiuser parallel interference cancellation receiver in most cases with a smaller computational cost     

Energy-saving scheduling for LTE multicast services

In the Long Term Evolution （LTE） downlink multicast scheduling, Base Station （BS） usually allocates transmit power equally among all Resource Blocks （RBs）, it may cause the waste of transmit power. To avoid it, this paper put forward a new algorithm for LTE multicast downlink scheduling called the Energy-saving based Inter-group Proportional Fair （EIPF）. The basic idea of EIPF is to calculate an appropriate transmitting power for each group according to its data rate respectively, and then follow the inter-group proportional fair principle to allocate RBs among multicast groups. The results of EIPF simulation show that the proposed algorithm not only can reduce the transmit power of BS effectively but also improve the utilization rate of energy.     

光交换技术及其在WDM全光网中的应用

本文阐述了光交换技术的基本概念及其意义，对光交换在ＷＤＭ全光网中的应用及其关键技术分析和讨论近期内，ＷＤＭ全光通信网的实用化进程将在很大程度上取决于ＷＤＭ光交换技术的发展。     

颜料分散法制备LCD用彩色滤色膜

记述了采用颜料分散法制备彩色滤色膜的工艺过程。在着色光刻胶的制备方法作了一些研究，测定了所制滤色膜的分光特性及色度性能，并对彩色滤色膜的耐热性，耐药品性，耐侯性进行了检验。     

砷化镓单晶片抛光工艺研究

由于砷化镓（ＧａＡｓ）及其它化合物半导体具有很重要的作用，目前对它们的工艺研究越来越多。本文主要介绍了一种比较成熟的ＧａＡｓ单晶片抛光工艺。