PIC Compatible MCU's Circuit Analysis and Design

随着微电子技术的飞速发展，作为电子系统核心的集成电路。一直遵照着摩尔定律在发展，集成度方面，已经能在单芯片上集成几百万、上千万晶体管。同时，芯片的功耗越来越低，工作速度越来越高。如今在单芯片上集成一个系统，即所谓的系统芯片（SOC）已成为可能。集成电路业进入系统芯片时代后，在芯片设计中采用IP核（知识产权）是设计发展一个必然选择，基于IP核复用的自顶向下的设计可提高设计效率，节省人力和满足面市时间的要求。 基于IP的设计的关键显然是各种性能优异、方便重用的IP核。IP核可分为硬核、固核和软核。其中的硬核依赖特定的工艺库，目前主要来源是外国的IP专业供应商，设计服务公司和代工厂。而软核是一个仅...With the development of microelectronics technology, the core of electronics system, Integrated Circuits, have made great progress to integrate millions of transistors in a single chip with lower power consumption. It’s possible to build a system in a single chip to construct so call System On Chip (SOC) today. In order to improve the efficiency and shorten the time for new products to enter into ...学位：理学硕士院系专业：计算机与信息工程学院电子工程系_无线电物理学号：20013000

The Research of Interferences Mitigation Algorithms for Wireless Repeaters

随着通信技术的发展，无线中继在现有系统以及未来的分布式协同通信系统与网络中起着重要的作用。在同频同时收发的情况下，覆盖天线信号容易反馈至施主天线，造成系统的自激振荡。而且中继系统一般输出功率较大，因而容易受到功率放大器等设备非线性效应的影响，产生带内失真和带外频谱扩展，对邻近信道产生干扰。因此，中继技术在获得覆盖和容量增益的同时，往往也产生了新的干扰源，导致了更复杂的干扰结构。其中反馈自激和带外泄漏是两种主要的干扰源，论文采取的抑制方法是自适应噪声抵消和基于数字预失真的功放线性化技术。 本文包含反馈干扰抵消和带外抑制算法研究两大部分。其中的反馈干扰抵消部分主要针对最小均方(LMS)算法收敛速...With the development of communication technology, wireless relay systems play an important role in existing and future distributed cooperative communication systems and networks. Signals from service antenna are apt to feed back to donor antenna in the case of working on the same frequency and same time, which causes the system into self-oscillation. Furthermore, due to their large output power, w...学位：工学博士院系专业：信息科学与技术学院_通信与信息系统学号：2332007015387

Complex ICA based adaptive feedback interference cancelling algorithm for wireless repeaters

为了利用自适应滤波器抵消转发与接收天线间的反馈干扰,根据卷积型混合与独立分量分析ICA解混的原理,将反馈干扰抵消问题纳入了ICA方法的框架中。针对亚高斯复值信号的特点,依据极小化互信息的准则,提出了一种基于复数ICA的自适应算法,简要分析了算法收敛的平衡点并据此给出了新的干扰抵消器的结构。计算机仿真结果表明,相比于lMS算法,所提的算法在反馈信道辨识误差以及输出信号的误差矢量幅度方面有明显的改善。Feedback interference cancelling by using adaptive filters is one of the core technologies of wireless repeaters.The problem was summed up into the framework of ICA in terms of the ICA demixing principle of convolutive mixtures.Aiming at complex signals' subgaussian feature,an adaptive algorithm based on complex ICA was proposed according to minimization of mutual information criterion.The convergence equilibrium point of the proposed algorithm was briefly analyzed and a new structure of interference canceller presented accordingly.Computer simulation demonstrated that the proposed algorithm had obvious performance improvement over conventional LMS in the identification error of feedback path and of the error vector magnitude the output signals'.国家863计划资助项目(2007AA01Z267);福建省重大专项基金资助项目(2009HZ0003-1);福建省教育厅科技项目(JA10251

自适应回波抵消器的算法与MATLAB仿真

1、线路回波产生的背景 在电信网中,为了降低电话中心局与电话用户之间电话线的价格,用户线的连接采用两线制;电话中心局之间连接采用四线制。为了适应四线到二线或二线到四线的连接,需要使用二线到四线的混合电路

MLSSA electro-acoustic analyzer system and its reconstruct for automation

介绍美国DRA实验室研制的基于最长序列MLS信号测试技术的扬声器电声分析系统MLSSA。同时给出对其进行自动化改造的思路及方法,经改造后该系统能适应扬声器工厂生产线大批量测试产品频率响应的需要。对扬声器生产工厂的质量控制有一定意义。A brief introduction to MLSSA(Maximum-Length Sequence System Analyzer)is presented,which is developed over the MLS signal theory by DRA laboratories,U.S.A.A method is also given to reconstruct the system in order to use it to test loudspeakers quickly for manufacturer's mass-produc-tion.The reconstructed system is of certain benefit to manufactarer's quality control.

An Improved SNR Based Variable Step Size LMS Algorithm and Its Application

在无线直放站反馈干扰抵消的过程中,自适应滤波器的误差信号可以接收目标信号与残余回波的混合,是阻碍滤波器根据残余回波强度,快速调整抽头系数.利用误差信号的特点,给出了一种基于信噪比的改进变步长最小均平方(lEAST MEAn SQuArE,lMS)自适应算法.该算法利用误差信号和滤波器的输出信号作为目标信号和反馈干扰信号的估计,根据目标与干扰信号的功率比值来调整自适应滤波器的步长.计算机仿真结果表明,该算法具有快速的初始收敛速率和较小的超量均方误差.在稳态情况下,对于干扰的突变能够快速地再次收敛,表明该算法在反馈干扰抵消方面的性能优于已有的算法.During the feedback interference cancelling of wireless repeaters,the error signals of adaptive filters are mixtures of target signals and residual echoes,which hinder the filters from rapidly adjusting their coefficients according to the strength of residual echoes.An improved SNR(signal noise ratio) based variable step size LMS(least mean square) adaptive algorithm is presented using the characters of the error signals.The algorithm makes use of the error signals and the filters′ output signals as the estimation of target signals and feedback interference signals,and adjusts the adaptive filters′ coefficients according to the power ratio of target and echo signals.Computer simulations demonstrate that the proposed algorithm has a rapid initial convergence speed and a small excess mean square error.The algorithm is able to converge again rapidly in the case of an abrupt change of interference when it has been in a stable state,which confirms that the proposed one is superior to former algorithms in terms of the cancelling performance.福建省科技重大专项项目(2009HZ0003-1);福建省教育厅科技项目(JA10251);(JB10146);厦门市科技计划项目(3502Z20103038

AccelDSP Based Adaptive Filter Design

给出了一种自适应滤波器的设计和fPgA的实现方法.简要分析了最小均方误差(lMS)、归一化最小均方误差(nlMS)和延迟最小均方误差(dlMS)自适应滤波器的工作原理,指出了3种滤波器的区别和联系.详细介绍使用XIl-InX公司的ACCEldSP高层次设计工具设计自适应滤波器的流程与方法,说明了可综合MATlAb语言的结构特点,提高硬件使用效率的途径等设计细节,得到了设计代码和仿真结果.设计经过硬件时序仿真验证,可以在fPgA中直接实现.仿真结果说明,nlMS滤波器对于音频信号有很好的收敛特性,dlMS滤波器可以达到很高的工作频率设计.设计方法对于其它数字信号处理系统的设计和实现具有参考价值.设计过程表明ACCEldSP工具可以显著地提升数字信号处理系统的设计效率.A design approach and FPGA implementation method of adaptive filters is presented in this paper.Working theory and differences of LMS,NLMS and DLMS adaptive filters is shortly analyzed.Using Xilinx′s AccelDSP tool,the details of design flow,synthesizable MATLAB constructs and improving hardware using efficiency method,with part of the code and simulation results,is presented as well.The design is verified by timing simulation,and can be implemented on FPGA directly.It is shown by simulation results that NLMS filters have a better convergence character,while DLMS filters have a higher working frequency.The design approach can be a good reference to other digital signal processing systems.And the design process demonstrates that AccelDSP can remarkably improve the design efficiency of DSP systems

新疆气候变化及短期气候预测综合系统研究

该项目提出了现代气候观新概念，并深刻地阐述了其科学内涵，并研究指出现代气候观是一个相互联系和作用的观念系统包括气候系统观、气候资源观、气候环境观、气候变化观、气候层次观。项目还揭示出新疆气候变化和三大气候灾害——新疆春季水旱、夏季洪涝和夏秋季低温冷害的若干新现象、新事实，并对其形成原因、物理机制和预测应用进行了新的探索，同时研制成了2000新一代《短期气候预测综合业务系统》。该项目研究与世界气象组织提出的全球气候变化研究规划在时间上恰好是一致的，并始终紧贴自治区以一白(棉花)一黑(石油)为重点的优势资源转换发展战略和以生态环境保护和建设为根本和切入点的西部大开发战略，坚持边研究、边行动、边应用的原则，在“用”上下功夫，取得了显著的社会、经济、环境和气象业务效益

CMIP5模式对中国西北干旱区模拟能力评价/Evaluation of CMIP5 modes's simulation ability in the northwest arid areas of China[J]

气候模式是研究气候系统和气候变化的重要工具,气候模式结果是进行气候预测和气候变化风险评估的重要依据.基于中国西北干旱区78个气象站点1960-2005年的观测数据,对最新公布的CMIP5的39个模式在中国西北干旱区1960-2005年平均气温、降水的模拟能力进行评估.结果表明:多个模式模拟年平均气温与观测值的相关系数达到0.39,夏、秋季节的相关系数好于春、冬季,年平均气温模拟大多偏低2℃以上,其中MIROC4h、CCSM4和CMCC-CM对年平均气温的模拟绝对误差较小.模拟的年、季降水量与观测值的相关系数很差,均不到0.1.年降水量模拟普遍偏高100 mm以上,其中CMCC-CM、CNRM-CM5和MRI-CGCM3对年降水量模拟绝对误差较小.年际变化趋势上,模拟的平均气温升高趋势和降水量增加趋势均比观测趋势要低,模拟的冬季平均气温升高趋势偏低最明显,达-0.21℃/10 a,模拟夏季的降水量增加趋势偏低最明显,相对误差达-99％.CMIP5模式对中国西北干旱区的模拟效果整体上偏差较大,未来无论从物理过程还是模式算法都需要进一步研究和改进