查询词典 digital signal processing

a kind of design project of multifunction electric power quality gauged instrument based on virtual instrument is put forward in this article.this system integrates virtual instrument programming and power electronics together,to realize diverse signals of current electric power quality field allin one.the integrated signal generator unit which carries out the collection of high speed digital data,d/ a conversion and analog output in four channels,unsymmetrical synchro control fifo etc.by fpga are introduced,the flow of electric power system various signal which generates by vc programming is elaborated,and the structural design of signal amplification unit is analysed.the experiment text result shows that this gauged instrument has attained current advanced high grade of accuracy and it will accelerate the steps of electric power quality calibration because of its accuracy and versatility.

摘 要：提出一种基于虚拟仪器技术的多功能电能质量标定仪的设计方案，采用虚拟仪器编程技术和电力电子技术相结合实现集目前电能质量领域的多样信号于一体。介绍采用fpga实现高速数字量采集、d/a转换及4通道模拟量输出、非对称同步控制fifo等的集成信号发生单元，阐述利用vc编程实现的电力系统多样信号的产生流程，分析信号放大单元的结构设计。实验测试结果表明该标定仪达到目前先进的高精度等级，由于其准确性和多功能性将加快电能质量标定的步伐。

After that, the issue, which should be solved in the picture additive process, is discussed in detail. On the base of analyzing digital television signal data construction, TBC processes is put forward to apply in each group signal. Effective data taken off from the key signal is also solved. And the choice and insertion is used to protect assistant data.

接着，详细讨论了在图像叠加过程中应解决的问题，在分析了数字电视信号数据结构的基础上，提出了对各路信号进行TBC处理的方法，同时解决了对键信号进行有效数据提取的问题，并通过选择插入的方式对辅助数据进行了保护。

Circuit principles, analogue circuit, digit circuit which laid me a solid foundation of circuit for the study of communication; the study of electronic circuit of communication provided me with the working principles of analog communication system; the study on communication theory made me grasp the working methods of digital communication; the study on electromagnetic field, electromagnetic wave and aerial let me know that how signals travel through signal paths and how to apply signal and linear system, random signal and system to the research of noise's impact on signals

学习了电路原理、模拟电路、数字电路打下了学习通信的电路基础；学习了通信电子线路掌握了模拟通信系统的工作原理；学习了通信原理掌握了数字通信的工作方法；学习了电磁场与电磁波、微波与天线了解了信号如何在信道中传输；学习了信号与线性系统和随机信号与系统来研究噪声对信号的影响。

Introduces an adaptive fuzzy filter based on approximate entropy and applies the filter to the digital filter of rocket telemetry signal in the wideband noise The adaptive fuzzy filter algorithm is discussed, and the experimental filtering results of rocket telemetry signal in white noise are given Both analysis and experiment show that the parameters of this novel filter can adjust itself according to the complexities of the signal It filters better than the average subsection fuzzy filter for the no...

介绍了一种基于估计熵的自适应模糊滤波器，并将其应用于宽带噪声中火箭遥测速变信号的数字滤波。讨论了自适应模糊滤波算法，给出了应用实验结果。分析和实验表明，这种新型滤波器能根据信号的复杂程度自动调节其参数，对宽带噪声中非平稳随机信号有较好的滤波效果

That is to say, by using the special digital converter or running relevant arithmetic, it converts the radio signal to intermediate frequency signal and completes the base-band signal process that isn"t the veriest SR and is named "software defined radio. This paper introduces the rapid system prototype into the design of software radio system, which has great advantage because rapid system prototype technology can be used to describe the future application.

由于受到硬件性能如A／D、D／A及DSP芯片处理速度的限制，目前的软件无线电系统多采用折中的实现方案，增加专用的数字变频器或者运行数字变频算法，将射频信号变频到中频，然后再进行基带信号处理，这样的软件无线电系统又被称之为"软件定义无线电"，它并不是真正意义上的软件无线电。

Because the traditional wireless microphone uses the frequency low silent chain, all is analyzes the radio-frequency signal the intensity, therefore they cannot and need the noise the signal differentiates; In the noisy radio frequency environment (for example digital equipment and so on CD/VCD/LD send out massive overtones) under use, when this launcher signal weak or closure, the silent chain possibly can open suddenly, the receiver can send out the intense demolition noise.

传统无线麦克风因采用频率低的静噪电路，都是分析射频信号的强度，所以它们不能把噪音和需要的信号区分开来；在嘈杂的射频环境(如CD/VCD/LD等数码设备散发出的大量谐波)下使用，在该发射器的信号微弱或关闭时，静噪电路可能会忽然打开，接收机就会发出强烈的爆破噪声。

By using Digital-Trailing-Filter and DSP technology, we got solution of trailing filter for transient signal in frequency-scan test,so as to refine the needed test signal from the deformative and weak signal.

通过采用数字跟踪滤波和DSP处理技术，解决了扫频测量中瞬态信号的跟踪滤波，使仪器能够在畸变的、微弱的信号中提取出需要的测试信号，同时使仪器的测量时间大大缩短。

By time-varying filtering, we realize the signal selectivity and interference suppression, especially for the signals with time-varying power spectrum. It is shown herein that conventional eigenstructure based methods are lower dimensional special case of the time-frequency subspace fitting method. The closed-form array response estimation algorithms for blind source separation in wireless communication is also developed in the dissertation by exploiting the data structure of second-order statistics of the array output in the presence of multipath. The proposed method achieves array response estimation with little constraint on signal property and propagation environment such as scatters or angular spread. Moreover, the array utilized here can be of arbitrary geometry and even uncalibrated. Since the closed-form solution is obtained, no misconvergency may occur and large amount of computation can be saved. The equivalent feed model and corresponding optimization designation are proposed to realize the downlink multi-user selective transmission. By coherent and non-coherent superposition of the electromagnetical field, multiple beams can be formed using a single array, so that each co-channel user signal is transmitted in each beam and will not interfered with each other. The proposed system scheme implements the digital beamforming and the channel allocation in the base band, therefore is suitable for the utilization of the radio software technology. The feasibility and effectiveness of the proposed model are proved by the RF experiment.

在窄带条件下，GSC－SSF方法还可以提高阵列的虚拟孔径，从而提高估计的性能；可以证明，Cyclic DOA 和SC-SSF方法可看作该方法的特例或近似； 3、提出了二维GSC－SSF方法和宽带谱相关DOA矩阵方法，利用信号的循环平稳特性解决了宽带条件下二维 DOA 估计问题，并具有阵元数少、计算量较小的特点； 4、提出了时频子空间拟合和宽带时频DOA估计算法，将联合时频分析的理论和方法引入到阵列信号的空间谱估计研究中，利用时变滤波实现信号选择性测向和干扰抑制，特别适合于谱时变信号；可以证明传统特征结构法可看作是时频子空间拟合方法的特例； 5、提出了多用户环境下阵列响应的估计方法——CARE方法，该方法对信号结构和传播参数（主要是散射源分布与角度散布）的约束较少，适用于各种几何结构的阵列甚至未校准的阵列，能够直接得到阵列响应的闭式解，因此计算量小、稳健性好，不存在收敛问题； 6、提出了针对多用户下行选择性发送的阵列等效激励模型、优化设计方法及其系统实现方案，通过空间场的相干叠加与非相干叠加使得单一阵列能够形成多个波束，并保证各波束内的用户信号各不相同且相互干扰最小；其系统方案具有在基带实现数字波束成形、信道分配并便于软件无线电实现的特点，其有效性已得到外场实测数据的证实。

A digital phase synthesizer is composed of a continuous phase data signal source, an interpolater to generate continuous edge configuration data signals in response with each continuous phase data signal, and a phase modulator to generate ouput clock signal.

一种数字相位合成器包括一个连续相位数据信号源。一个内插器响应每个连续相位数据信号产生连续边沿配置数据信号。一个相位调制器产生具有放置在由连续边沿放置数据信号确定的时间的边沿的输出时钟信号。

The digital frequency source this paper researched uses high integrated DDS chip AD9851 as frequency sources and signal mirac processors AT89C51 as system control center, it can output 10Hz-20MHz signal with high-precision and high stability frequency. The evenness of signal within the range of 10MHz is low to 0.1dB degree, and the smallest step is low to 10Hz frequency.

本课题研究的数字频率源采用高集成度DDS芯片AD9851作为频率源；以单片机AT89C51作为系统的控制中心，实现了10Hz～20MHz的高精度、高稳定度的频率输出。10MHz内信号幅度的平坦度为0.1dB、频率最小步进为10Hz。

Now she was hungry and angry.She began to smoulder.

现在她又饿又气，她开始流露难以抑制的怒火。

You have placed our iniquities before You, Our secret sins in the light of Your presence.

诗90：8 你将我们的罪孽摆在你面前、将我们的隐恶摆在你面光之中。