数字信号

Interference is most difficult to be avoided while measuring the weak signal, Especially when the signal is only at microvolt level.X9313 is a kind of digitally controlled dissurbacne potentiometer produced by Xicor company.We succeed in using it to solve the problem that the signal is too strong, and get the useful signal in a weak signal measurement device.

微信号检测中最难避免的就是干扰问题，特别是在信号仅为微伏级时，信号相对于干扰来说，几乎被完全淹没，因此，研究如何在干扰信号很大的情况下尽可能地检测出有用信号有着极其重要的意义。X9313是Xicor公司推出的一种数字电位器，在某微弱信号检测装置中，采用X9313可成功解决干扰信号过大的问题。

Compared to the ordinary PLL circuits, it can endure the short time appearance that occurs once in a horizontal line of the sync signal. It can adapt to the phase alternation character of a PAL video signal and recognize the phase alternation line. The local color sub-carrier can be generated for synchronous demodulation by the circuit.

该电路使用了全数字锁相环对色同步信号进行跟踪，与普通锁相环电路相比，它不仅能适应制视频信号中色同步信号每行出现一次和PAL制信号逐行倒相的特性，还能识别倒相开关信号，准确地产生本地色副载波用于同步解调。

A DPC ( 300 ) includes: a frequency source ( 310 ) for generating a clock signal; a delay line ( 320 ) for receiving the clock signal and generating phase-shifted clock signals at output taps; a digital control device ( 330 ) for generating a control signal; and a windowing and selection circuit for generating the output signal, that includes sequential logic devices ( 500, 510, 520 ) and a combining network.

DPC(300)包括：频率源(310)，用于产生时钟信号；延迟线(320)，用于接收时钟信号并在输出抽头产生相移时钟信号；数字控制器件(330)，用于产生控制信号；以及开窗口与选择电路，用于产生输出信号，包括：时序逻辑器件(500、510、520)和组合网络。

In Broad Band ,Curcuit signal graphics is achieved by oscillograph ,and packet loss rate , throughput, Latency , back-to-back and so on.;In VoIP, the device can communicate with FXO 3804 of TAIWAN Welltech and DT60 of BEIJING JIAXUN FEIHONG, At that time, Ethereal and PalmTool of PA1688 testing are introduced; In CATV, flatness ,signal graphics of radio frequency are tested by CATV stroboscope.

使用示波器测试数据部分的电路信号波形，使用网络分析仪测试丢包率、吞吐量、时延和背压等以太网指标的测试，并记录最终测试结果；电话部分主要是与台湾伟桥的FXO 3804和北京佳讯飞鸿的E1数字中继网关DT60，实现基于H.323协议的VoIP电话通信，同时介绍使用Ethereal软件和PA1688专用测试工具PalmTool的测试分析情况；电视部分主要是使用CATV频谱仪测试输出射频信号的平坦度、信号波形等分析信号质量，并通过实际电视接收观察输出的射频信号质量。

The frequency spectrum of noise is very wide, and will superpose with useful signal that has the notable influence to digital measurement and frequency spectrum analysis. Base on it, the method of solving zero floating problem of Waveform digital reconstruction process is proposed.

噪声的频谱噪声频谱很宽，将与有用信号的频谱重叠，对数字测量、信号处理和谱分析有显著的影响，并提出了解决波形数字重构中数字示波器零漂影响的方法。

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。

In this paper, based on the analysis of the IF GPS signal theoretic model, a digitized GPS signal generator is implemented in Matlab, which can generate the received GPS signal at the digitized IF frequencies, and the noise and receiver clock error are also simulated.

本文在中频GPS信号理论模型分析的基础上，用Matlab实现了一种数字GPS信号生成模型，它能够在数字中频上产生GPS接收信号，其中包含仿真的噪声和接收机时钟误差。

The kernel of thecontrol system hardware is an industrial control PC, voltage AD, current AD anddigital input/output plates are equipped to respective signals collected, which collectand control main parameters of transmission assembly. For the convenience of wiringand signal modulating, a harness plate adapting to collection plate is configured.

测控系统的硬件以一台工业控制PC机为核心并根据采集信号的性质配置了电压-数字量转换板、电流-数字量转换板及数字量输入/输出板，对变速箱总成的主要参数进行采集和输入转速等的控制；为方便接线和信号调理，配备了与采集板对应的接线和调理接口板以及接线盒。

Agilent 54123T | HP54123T 34GHz, 4 passageways count word oscillograph An Jielun Brand: Oscillograph of 54123T of An Jielun of HP of HP of American An Jielun Agilent is undee indication instrument, it can be accurate the weaveform that describes telegraphic number, show in wide example application signal weaveform changes as the change of time, vertical axis is worth on behalf of undee voltage, horizontal axis represents time, the adjustment of brightness says for Z axis A kind of of oscillograph of An Jielun 54123T simple weaveform shows, the certain and special event that can help you discover to appear in telegraphic date weaveform, be like: Flatter pull Mou goes straight towards of Wei of ㄐ of haze of creek rapid pull to touch Su You to be worth lotus root of green of Lu of U of Fei of bursa post left-eyed flounder the sometime that " of?" drift part produces often in circuit weaveform paragraph or some part, whether does signal produce mutation and twist, the between change when noise signal and this noise signal containing to follow in the communication part that contains in signal and dc composition and undee signal Characteristic: The Gao Zhoubo with unapproachable * is characteristic * exceeds fanciful pulse width Converter of *12 digit model The lowermost time-interval of *0.25 skin second * is perpendicular and average measure mode Parameter of * automatic pulse is expressed * 4 passageways Voltage of time of * high accuracy is worth * HP attestation * for many times the brim sparks * time domain reflexes a function * digitlization filter

Agilent 54123T | HP54123T 34GHz、4通道数字示波器安捷伦品牌：美国安捷伦Agilent 惠普HP 安捷伦54123T示波器是波形显示仪器，它能正确形容电信号的波形，在宽泛的实例应用中显示信号波形跟着时候的转变而转变，垂直轴代表波形的电压值，程度轴暗示时候，亮度的调整称之为z轴安捷伦54123T示波器的一种简单的波形显示，能够帮助你发现电信号波形中呈现的某些特别事务，如：在某个时候和某个波形幅值之间呈现的一个异常震动信号，%26rdquo；漂移部门%26rdquo；相对频繁地发生在电路波形中的某一时候段或某一部门，信号是否发生变异和扭曲，信号中所含的交流成分和直流成分以及波形信号中所含噪声信号以及该噪声信号随时候的转变特点：*无与伦比的高周波特征*超乎想像的脉冲宽度*12位数模转换器*0.25皮秒的最低时候距离*垂直平均测量模式*主动脉冲参数表*四个通道*高精度时候电压值*惠普认证*屡次的边缘触发*时域反射性能*数字化滤波器

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。