Take the hoc based blind modulation detection algorithm as an example , the relationship between the blind modulation detection algorithm and synchronization is investigated . an unproved detection algorithm robust to frequency offset is proposed which solves the problem caused by the error in carrier synchronization . how to synchronize a received signal with unknown modulation type is studied and a blind algorithm to estimate symbol timing of the signals with unknown modulation type is presented 研究了载波同步和码元定时同步与调制方式盲检测算法的关系；以自适应单载波中高阶累积量调制方式盲检测算法为例，对于载波同步误差引起的频偏问题，提出一种基于频偏稳健的mdpsk信号调制方式盲检测算法；对于未知调制方式信号的定时同步问题，提出一种盲定时估计算法，该算法可以估计mdpsk和mqam信号的定时同步信息，实现数字信号的同步分类；提出了一种基于调制方式盲检测的自适应接收机结构，把调制方式盲检测，信噪比估计和同步解调联合起来进行，实现调制方式随信道质量而自适应变化的信号的正确接收。
Power transformer test is simulanted in test - room , try to prove that online measure of transformer test is feasible . the test results are satisfaction . in the end , there is software design : the instrumented - test - interface is developed ; location computer entering to sample state is the same time , and after the same " log time " , it stops the data sample note . every test signal data keeping in the data note memorizer is at the same time , so it realizes data synchronization collection . some blocking design in the process of software design can apply to the other software 文章的最后，针对变压器试验微机测试系统对电流、电压、功率等变量数据采集的特殊要求，分析了同步误差的产生原因，给出了同步软件采样的无差条件；建立了电压电流有效值和平均功率测量误差的数学模型，提供了减小测量误差的措施；应用“同步软件采样技术” ，不需要增加采样周期数，不需要硬件同步环节，较好地解决了同步误差对测量精度的影响。
The future wireless mobile communication systems are expected to provide ubiquitous , high - quality , and high - rate mobile multimedia transmission . however , hostile multipath fading radio conditions give rise to serious inter - symbol interference ( isi ) ; even worse , wireless channel are often time varying , which makes the system more vulnerable and more difficult to track the channel state . orthogonal frequency dvision multiplexing ( ofdm ) , which is inherently resistant against isi , has invoked a popular research interest in recent years , and has been a promising candidate technology of the physical layer for future weideband high - date - rate wireless communications . notwithstanding , ofdm is much more vulnerable to errors of both time and frequency synchronization and to that of channel estimation , and how to obtain correct timing and channel estimation efficiently is highly critical to ofdm systems . the dissertation will focus on both of the aspects of ofdm systems mentioned above 但是无线环境的多径特性造成通信系统中严重的符号间干扰,同时无线信道的时变性使得信道特性跟踪复杂。而正交频分复用技术( orthogonalfrequencydivisionmultiplexing , ofdm )正是一种解决符号间干扰的有效传输手段,因此ofdm技术作为未来宽带高速率无线通信的物理层候选技术在当前引起了一股研究热潮。但ofdm系统对定时同步误差和信道估计误差非常敏感,如何在ofdm系统中准确快速地实现符号同步和信道估计是至关重要的,本论文将重点针对这两个问题进行讨论。
The typical peer to peer telecontrol protocol dnp 3 . 0 is analyzed on the real time performance of data transmission , the transparency of layered function and the scientificity of frame format definition . the valid classification method and the gathering procedure of telecontrol information are presented so as to improve real time performance of telecontrol information transmission . the rules to be obeyed in program realization are summed up in insuring the reliability of telecommand and teleadjusting 分析了典型对等式远动规约dnp3 . 0规约中数据传输的实时性、分层功能的透明性以及帧格式定义的科学性；提出了一种远动信息有效分类方法和收集过程提高远动信息传输的实时性；总结了为保证遥控和遥调的可靠性在程序实现中应遵守的规则；分析了dnp规约时间同步中同步误差的产生原因，并给出了改进方法；提出一种实现远动技术中参数设置的可行方法。
Comparing and analyzing the synchronous control strategy , which brings up the new method to control the double un - symmetry jars proceed synchronously with the combination of proportional valve and servo valve , which forms closed loop control ; basing on the above methods , models are made to get mathematics models of position control system and to analyze system model theoretically by using pid controller , we can realize regulating parameters , minimizing synchronous errors and enhancing the dynamic performances ; the simulink tool box in matlab software is used to imitate the system according to the model , which not only makes the result visual and easy to adjust the parameters in interactive way but also lets us understand the effects of different parameters and optimizes the dynamic properties . the theory of plc control in dshp is discussed after advanced understanding of the system movements . hardware design and general regulation are given on the base of siemens company products s7 - 200 plc 本文根据大量的国内外文献，对研配液压机的工作原理及设计结构进行了简介；对位置同步的控制方法进行了比较分析，提出比例阀和伺服阀复合控制的闭环结构来对非对称双缸进行同步控制电液比例同步控制方案；在此基础上着重对比例阀控非对称缸建模，最后得到位置控制系统的总体数学模型，从理论上对同步系统动态特性进行了分析，并用pid控制器进行参数整定，减小双缸同步误差、提高系统的动态响应性能；其中控制性能的分析借助于matlab软件中的simulink工具箱，由已建立的数学模型形成仿真模型，得到可视化的仿真结果，从而利于交互方式下调整参数，了解不同的参数对系统的影响，优化同步系统的动态性能；在深入了解系统的动作特性后，对plc控制研配液压机的原理进行了探讨，针对siemens公司s7 ? 200型plc给出了硬件设计的总体规划，编制出研配液压机动作控制程序，在编程中着重研究位移传感器与plc的通讯、双缸同步运行的pid控制在plc上的实现及bcd码拨盘输入程序的植入问题。
