基于自然数编码的模式理论研究

在分析基于二进制编码的遗传算法基础上,对基于自然数编码的遗传算法作了初步的探讨。论文定义了基于自然数编码的模式和模式的阶,并推导出了相应的模式理论,从而得出了该理论与基于二进制编码的模式理论相类似的结论,对于解释基于自然数编码的遗传算法的收敛性具有一定的意义。     

AR自编码扩频通信系统的研究

在自编码扩频通信原理的基础上,介绍了利用自回归(Auto-Regressive,AR)滤波的方法从信源序列中提取扩频码的AR自编码扩频系统,并对该系统的误码性能和多址通信能力进行了理论分析和仿真.结果表明,AR自编码扩频系统改善了普通自编码扩频系统的误码性能,提高了系统的多址能力,为自编码扩频通信的实际应用提供了可选的方案.     

AR自编码扩频通信系统的研究

在自编码扩频通信原理的基础上,介绍了利用自回归(Auto-Regressive,AR)滤波的方法从信源序列中提取扩频码的AR自编码扩频系统,并对该系统的误码性能和多址通信能力进行了理论分析和仿真.结果表明,AR自编码扩频系统改善了普通自编码扩频系统的误码性能,提高了系统的多址能力,为自编码扩频通信的实际应用提供了可选的方案.     

曼彻斯特编码的解码及其应用

本文介绍了一种抗干扰能力较强而且也是比较常用的编码形式-曼彻斯特编码,针对这种编码形式的特点,给出了两种在单片机中的解码方法,并对这两种方法进行了简单的比较。最后在文章中给出了曼彻斯特编码在实际中的应用例子-ID卡的解码程序,主要针对的是现在国内比较常见的ID卡EM4100和基站芯片U2270B。     

CRH3型动车组故障诊断代码编码规则研究

在分析研究CRH3型动车组普遍采用的故障诊断代码编码规则的基础上,对其编码规则进行了改进,并提出了新的故障诊断代码编码规则：“四位故障编码规则”和“五位故障编码规则”.通过对比分析,讨论了故障诊断编码规则各自的优缺点,最终提出：新四位故障诊断代码编码规则具有“采用了《通知》规定的系统划分方法,扩充了故障等级编码的取值,保证每个子系统都有足够的故障诊断代码”等优点,故建议在CRH3型动车组故障诊断系统中采用.     

基于波变换的图象压缩编码的研究

在对近几年图象编码的新方法进行归纳的基础上，研究了这几种图象编码方法的内在联系，重点研究了小波变换和直接映射编码（向量量化编码）之间的关系，对于经过小波变换后的子图象，分别采用了小波变换结合霍夫曼编码和小波变换结合向量量化编码的实现方法，对这两种编码方法做了比较，研究了在小波变换的基础上进行直接映射的有关问题，为进一步研究小波及其应用，图像编码和分析提供了基本算法程序。     

交通基本建设工程试验检测数据报告编码体系的研究

结合目前交通基本建设工程实际,建立试验检测数据报告编码体系,并制定相应规则,针对使用中的特殊情况进行特例处理,保证了编码体系的完整性与编码的有效性、科学性。     

基于遗传算法的路径安排

讨论了城市道路中的路径安排问题,对遗传算法的编码问题进行了改进,并使用了一种新的编码机制.最后,运用VC 解决了城市道路的最短路径问题.     

基于网络编码的无线多跳自组网连接性增强

为了向无线多跳自组网的规划与设计提供依据,分析了物理层网络编码和网络编码分集对无线多跳自组网连接性的影响.通过对网络可供维持的路由跳数的理论推导和数值分析发现,与物理层网络编码协作发射相比,网络编码分集协作发射能极大地提高系统可供维持的路由跳数,其增益达3以上,极大地增强了网络连接性,从而提高了网络的吞吐量.     

基于关键帧的开环-闭环混合FGS编码框架

为提高FGS的编码效率,提出了一种基于关键参考帧的开环-闭环混合FGS编码框架.对非关键帧采用单预测环路的开环结构,以提高编码效率;周期性地插入一些使用双预测环路闭环结构的关键帧,以控制开环结构导致的预测漂移.此外,为更好地利用带宽,提出了一种相应的码流截取方式,将码率优先分配给对序列整体质量贡献更大的关键帧.实验结果表明,较之JVT SVC中的AR-FGS,混合FGS编码框架在极宽的码率范围内提高了编码效率,PSNR值平均提高了1～2 dB.     

A SPEAKER ADAPTABLE VERY LOW BIT RATE SPEECHCODER BASED ON HMM

IntroductionPhonetic and segmentvocoders are popular tech-niques used in speech coding at rates on the or-der of 1 0 0 bit/s.These coders are based onrecognition/synthesis technique.They use somekind of speech recognition technique to decom-pose speech signals to sequence of speech units,such as phonetic units or speech segment units,and then transmit indexes and durations of therecognized units.The decoders receive this in-formation,and synthesize speech by concatenat-ing typical instances of…     

A Concatenated ML Decoder for ST／SFBC-OFDM Systems in Double Selective Fading Channels

This paper presented a concatenated maximum-likelihood (ML) decoder for space-time/space-frequency block coded orthogonal frequency diversion multiplexing (ST/SFBC-OFDM) systems in double selective fading channels. The proposed decoder first detects space-time or space-frequency codeword elements separately. Then,according to the coarsely estimated codeword elements, the ML decoding is performed in a smaller constellation element set to searching final codeword. It is proved that the proposed decoder has optimal performances if and only if subchannels are constant during a codeword interval. The simulation results show that the performances of proposed decoder is close to that of the optimal ML decoder in severe Doppler and delay spread channels. However,the complexity of proposed decoder is much lower than that of the optimal ML decoder.     

Design and Implementation of the Motion Compensation Module for HDTV Video Decoder

Introduction The HDTV format adopts MPEG-2MP@HLvideo standard for the encoding and decoding ofhigh definition video information[1].Motion com-pensation is one of the key techniques used to con-siderably decrease the time redundancy of a videosequence and make the format reach a high com-pression ratio.As for hardware implementation,however,the motion compensation module is one ofthe most computation-intensive and I/O intensiveparts in an HDTV video decoder[2],and thereforeit is also the…     

Improved List Sphere Decoder for Multiple Antenna Systems

An improved list sphere decoder （ILSD） is proposed based on the conventional list sphere decoder （LSD） and the reduced- complexity maximum likelihood sphere-decoding algorithm. Unlike the conventional LSD with fixed initial radius, the ILSD adopts an adaptive radius to accelerate the list cdnstruction. Characterized by low-complexity and radius-insensitivity, the proposed algorithm makes iterative joint detection and decoding more realizable in multiple-antenna systems. Simulation results show that computational savings of ILSD over LSD are more apparent with more transmit antennas or larger constellations, and with no performance degradation. Because the complexity of the ILSD algorithm almost keeps invariant with the increasing of initial radius, the BER performance can be improved by selecting a sufficiently large radius.     

单路口交通灯的控制与显示电路仿真设计

在Proteus环境下进行了单路交通信号显示与控制电路的模块化设计,使用译码电路完成了单片机选择与控制电路的设计。在MPlab环境下进行了PIC16F877单片机的编程,并通过2种软件的联合仿真分析,完成了单路口交通灯的控制与显示电路。     

利用最优化理论实现QAM信号非线性编码的解码

非线性编码与解码是现代数字通信对数字信号处理常用的一种技术.利用最优化原理,提出一种对QAM信号非线性编码进行解码的一种方法.该方法对于浮点运算和定点运算都是行之有效的,并且容易控制误差的范围.此方法已经成功的应用于商业化的通信产品设计中.     

汽车防追尾的车辆识别系统设计

详细介绍了一种基于汽车防追尾的图像处理识别系统.该系统由摄像机(CCD)、图像采集处理模块和车辆识别系统组成.由CCD摄取的图像,经视频解码器处理后再传给车辆识别系统进行图像的车辆识别判断.     

HI-FI AUDIO CODING TECHNOLOGY FOR ISDN

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Improved Sinusoid Analysis and Post-Processing in Parametric Audio Coding

This paper proposed improvements to the low bit rate parametric audio coder with sinusoid model as its kernel. Firstly, we propose a new method to effectively order and select the perceptually most important sinusoids. The sinusoid which contributes most to the reduction of overall NMR is chosen. Combined with our improved parametric psychoacoustic model and advanced peak riddling techniques, the number of sinusoids required can be greatly reduced and the coding efficiency can be greatly enhanced. A lightweight version is also given to reduce the amount of computation with only little sacrifice of performance. Secondly, we propose two enhancement techniques for sinusoid synthesis: bandwidth enhancement and line enhancement. With little overhead, the effective bandwidth can be extended one more octave ; the timbre tends to sound much brighter, thicker and more beautiful.     

A synthetic decoding method of 3GPP multimedia broadcast/multicast services raptor codes

The 3GPP multimedia broadcast/multicast services （MBMS） standard takes Raptor codes as a way of channel coding and puts forward an efficient enhanced Gaussian elimination （EGE） for the Raptor decoder. However, the standard decoding method is not the most efficient. A few of researchers made some changes based on the standard decoding method and achieved considerable performance. In this paper, a synthetic decoding method is presented according to the existing enhanced decoding method and the simulation shows that the syn- thetic way outperforms any other ways.